Genetic Variation in Complement Component 2 of the Classical Complement Pathway is Associated with Increased Mortality and Infection: A Study of 627 Trauma Patients

PubMed Central

Morris, John A.; Francois, Cedric; Olson, Paul K.; Cotton, Bryan A.; Summar, Marshall; Jenkins, Judith M.; Norris, Patrick R.; Moore, Jason H.; Williams, Anna E.; McNew, Brent S.; Canter, Jeffrey A.

2009-01-01

Trauma is a disease of inflammation. Complement Component 2 (C2) is a protease involved in activation of complement through the classical pathway and has been implicated in a variety of chronic inflammatory diseases. We hypothesized that genetic variation in C2 (E318D) identifies a high-risk subgroup of trauma patients reflecting increased mortality and infection (Ventilator associated pneumonia: VAP). Consequently, genetic variation in C2 may stratify patient risk and illuminate underlying mechanisms for therapeutic intervention. Methods DNA samples from 702 trauma patients were genotyped for C2 E318D and linked with covariates (age: mean 42.8 years, gender: 74% male, ethnicity: 80% Caucasian, mechanism: 84% blunt, ISS: mean 25.0, admission lactate: mean 3.13 mEq/L) and outcomes: mortality 9.9% and VAP: 18.5%. VAP was defined by quantitative bronchoalveolar lavage (>104). Multivariate regression determined the relationship of genotype and covariates to risk of death and VAP. However, patients with ISS ≥ 45 were excluded from the multivariate analysis, as magnitude of injury overwhelms genetics and covariates in determining outcome. Results 52 patients (8.3%) had the high-risk heterozygous genotype, associated with a significant increase in mortality and VAP. Conclusion In 702 trauma patients, 8.3% had a high-risk genetic variation in C2 associated with increased mortality (OR=2.65) and infection (OR=2.00). This variation: 1) Identifies a previously unknown high risk group for infection and mortality; 2) Can be determined on admission; 3) May provide opportunity for early therapeutic intervention; and 4) Requires validation in a distinct cohort of patients. PMID:19430225

Fanconi anemia: correlating central nervous system malformations and genetic complementation groups.

PubMed

Johnson-Tesch, Benjamin A; Gawande, Rakhee S; Zhang, Lei; MacMillan, Margaret L; Nascene, David R

2017-06-01

Congenital central nervous system abnormalities in children with Fanconi anemia are poorly characterized, especially with regard to specific genetic complementation groups. To characterize the impact of genetic complementation groups on central nervous system anatomy. Through chart review we identified 36 patients with Fanconi anemia with available brain MRIs at the University of Minnesota (average age, 11.3 years; range, 1-43 years; M:F=19:17), which we reviewed and compared to 19 age- and sex-matched controls (average age, 7.9 years; range, 2-18 years; M:F=9:10). Genotypic information was available for 27 patients (15 FA-A, 2 FA-C, 3 FA-G, and 7 FA-D1 [biallelic mutations in BRCA2 gene]). Of the 36 patients, 61% had at least one congenital central nervous system or skull base abnormality. These included hypoplastic clivus (n=12), hypoplastic adenohypophysis (n=11), platybasia (n=8), pontocerebellar hypoplasia (n=7), isolated pontine hypoplasia (n=4), isolated vermis hypoplasia (n=3), and ectopic neurohypophysis (n=6). Average pituitary volume was significantly less in patients with Fanconi anemia (P<0.0001) than in controls. Basal angle was significantly greater in Fanconi anemia patients (P=0.006), but the basal angle of those with FA-D1 was not significantly different from controls (P=0.239). Clivus length was less in the Fanconi anemia group (P=0.002), but significance was only observed in the FA-D1 subgroup (P<0.0001). Of the seven patients meeting criteria for pontocerebellar hypoplasia, six belonged to the FA-D1 group. Patients with Fanconi anemia have higher incidences of ectopic neurohypophysis, adenohypophysis hypoplasia, platybasia and other midline central nervous system skull base posterior fossa abnormalities than age- and sex-matched controls. Patients with posterior fossa abnormalities, including pontocerebellar hypoplasia, are more likely to have biallelic BRCA2 mutations.

Variants in Complement Factor H and Complement Factor H-Related Protein Genes, CFHR3 and CFHR1, Affect Complement Activation in IgA Nephropathy.

PubMed

Zhu, Li; Zhai, Ya-Ling; Wang, Feng-Mei; Hou, Ping; Lv, Ji-Cheng; Xu, Da-Min; Shi, Su-Fang; Liu, Li-Jun; Yu, Feng; Zhao, Ming-Hui; Novak, Jan; Gharavi, Ali G; Zhang, Hong

2015-05-01

Complement activation is common in patients with IgA nephropathy (IgAN) and associated with disease severity. Our recent genome-wide association study of IgAN identified susceptibility loci on 1q32 containing the complement regulatory protein-encoding genes CFH and CFHR1-5, with rs6677604 in CFH as the top single-nucleotide polymorphism and CFHR3-1 deletion (CFHR3-1∆) as the top signal for copy number variation. In this study, to explore the clinical effects of variation in CFH, CFHR3, and CFHR1 on IgAN susceptibility and progression, we enrolled two populations. Group 1 included 1178 subjects with IgAN and available genome-wide association study data. Group 2 included 365 subjects with IgAN and available clinical follow-up data. In group 1, rs6677604 was associated with mesangial C3 deposition by genotype-phenotype correlation analysis. In group 2, we detected a linkage between the rs6677604-A allele and CFHR3-1∆ and found that the rs6677604-A allele was associated with higher serum levels of CFH and lower levels of the complement activation split product C3a. Furthermore, CFH levels were positively associated with circulating C3 levels and negatively associated with mesangial C3 deposition. Moreover, serum levels of the pathogenic galactose-deficient glycoform of IgA1 were also associated with the degree of mesangial C3 deposition in patients with IgAN. Our findings suggest that genetic variants in CFH, CFHR3, and CFHR1 affect complement activation and thereby, predispose patients to develop IgAN. Copyright © 2015 by the American Society of Nephrology.

A mutational approach for the detection of genetic factors affecting seed size in maize.

PubMed

Sangiorgio, Stefano; Carabelli, Laura; Gabotti, Damiano; Manzotti, Priscilla Sofia; Persico, Martina; Consonni, Gabriella; Gavazzi, Giuseppe

2016-12-01

Genes influencing seed size. The designation emp (empty pericarp) refers to a group of defective kernel mutants that exhibit a drastic reduction in endosperm tissue production. They allow the isolation of genes controlling seed development and affecting seed size. Nine independently isolated emp mutants have been analyzed in this study and in all cases longitudinal sections of mature seeds revealed the absence of morphogenesis in the embryo proper, an observation that correlates with their failure to germinate. Complementation tests with the nine emp mutants, crossed inter se in all pairwise combinations, identified complementing and non-complementing pairs in the F 1 progenies. Data were then validated in the F 2 /F 3 generations. Mutant chromosomal location was also established. Overall our study has identified two novel emp genes and a novel allele at the previously identified emp4 gene. The introgression of single emp mutants in a different genetic background revealed the existence of a cryptic genetic variation (CGV) recognizable as a variable increase in the endosperm tissue. The unmasking of CGV by introducing single mutants in different genetic backgrounds is the result of the interaction of the emp mutants with a suppressor that has no obvious phenotype of its own and is present in the genetic background of the inbred lines into which the emp mutants were transferred. On the basis of these results, emp mutants could be used as tools for the detection of genetic factors that enhance the amount of endosperm tissue in the maize kernel and which could thus become valuable targets to exploit in future breeding programs.

X and Y Chromosome Complement Influence Adiposity and Metabolism in Mice

PubMed Central

Chen, Xuqi; McClusky, Rebecca; Itoh, Yuichiro; Reue, Karen

2013-01-01

Three different models of MF1 strain mice were studied to measure the effects of gonadal secretions and sex chromosome type and number on body weight and composition, and on related metabolic variables such as glucose homeostasis, feeding, and activity. The 3 genetic models varied sex chromosome complement in different ways, as follows: 1) “four core genotypes” mice, comprising XX and XY gonadal males, and XX and XY gonadal females; 2) the XY* model comprising groups similar to XO, XX, XY, and XXY; and 3) a novel model comprising 6 groups having XO, XX, and XY chromosomes with either testes or ovaries. In gonadally intact mice, gonadal males were heavier than gonadal females, but sex chromosome complement also influenced weight. The male/female difference was abolished by adult gonadectomy, after which mice with 2 sex chromosomes (XX or XY) had greater body weight and percentage of body fat than mice with 1 X chromosome. A second sex chromosome of either type, X or Y, had similar effects, indicating that the 2 sex chromosomes each possess factors that influence body weight and composition in the MF1 genetic background. Sex chromosome complement also influenced metabolic variables such as food intake and glucose tolerance. The results reveal a role for the Y chromosome in metabolism independent of testes and gonadal hormones and point to a small number of X–Y gene pairs with similar coding sequences as candidates for causing these effects. PMID:23397033

Excision repair cross-complementing group 2/Xeroderma pigmentousm complementation group D (ERCC2/XPD) genetic variations and susceptibility to diffuse large B cell lymphoma in Egypt.

PubMed

El-Din, Mennat Allah Kamal; Khorshied, Mervat Mamdooh; El-Saadany, Zainab Ali; El-Banna, Marwa Ahmed; Reda Khorshid, Ola M

2013-12-01

Diffuse large B-cell lymphoma (DLBCL) is a genetically heterogeneous neoplasm. Although several genetic and environmental factors have been postulated, no obvious risk factors have been emerged for DLBCL in the general population. DNA repair systems are responsible for maintaining the integrity of the genome and protecting it against genetic alterations that can lead to malignant transformation. The current study aimed at investigating the possible role of ERCC2/XPD Arg156Arg, Asp312Asn and Lys751Gln genetic polymorphisms as risk factors for DLBCL in Egypt. The study included 81 DLBCL patients and 100 healthy controls. Genotyping of the studied genetic polymorphisms was performed by polymerase chain reaction-restriction fragment length polymorphism technique. Our results revealed that there was no statistical difference encountered in the distribution of -Asp312Asn and -Lys751Gln polymorphic genotypes between DLBCL cases and controls, thus it could not considered as molecular risk factors for DLBCL in Egyptians. However, Arg156Arg polymorphism at exon-6 conferred twofold increased risk of DLBCL (OR 2.034, 95 %CI 1.015-4.35, p = 0.43), and the risk increased when co-inherited with Lys751Gln at exon-23 (OR 3.304, 95 %CI 1.113-9.812, p = 0.038). In conclusion, ERCC2/XPD Arg156Arg polymorphism might be considered as a genetic risk factor for DLBCL in Egyptians, whether alone or conjoined with Lys751Gln.

Modulation of risk of squamous cell carcinoma head and neck in North Indian population with polymorphisms in xeroderma pigmentosum complementation Group C gene.

PubMed

Yadav, Suresh Kumar; Singh, Sudhir; Gupta, Shalini; Brahma Bhatt, Madan Lal; Mishra, Durga P; Roy, D; Sanyal, Somali

2018-01-01

Genetic variations in nucleotide excision repair genes can alter the risk of squamous cell carcinoma of head and neck (SCCHN). The present study has genotyped 334 subjects from North Indian population for xeroderma pigmentosum complementation Group C (XPC) rs2228001A>C, XPC rs77907221 polyadenylate (PAT) deletion/insertion (D/I), xeroderma pigmentosum complementation Group D - rs13181A>C, and xeroderma pigmentosum complementation Type G rs17655 G>C polymorphisms with polymerase chain reaction (PCR)-restriction-fragment length polymorphism or allele-specific PCR methods. Compared to D allele, I allele for XPC PAT D/I polymorphism was associated with significantly decreased the risk of SCCHN (odds ratios = 0.67, 95% confidence interval [CI] =0.48-0.94, P = 0.03). Haplotype CI constituted from XPC polymorphisms was also associated with decreased risk of SCCHN (P = 0.004). In contrast, haplotype Crohn's disease significantly increased the risk for SCCHN (P < 0.00). A significant early onset of SCCHN was observed in individuals with CC genotype for XPC A>C polymorphism (P = 0.004). Our results suggest a possible risk modulation for SCCHN with XPC polymorphisms in North Indian population.

Identification of Bacillus subtilis men mutants which lack O-succinylbenzoyl-coenzyme A synthetase and dihydroxynaphthoate synthase.

PubMed Central

Meganathan, R; Bentley, R; Taber, H

1981-01-01

Menaquinone (vitamin K2)-deficient mutants of Bacillus subtilis, whose growth requirement is satisfied by 1,4-dihydroxy-2-naphthoic acid but not by o-succinylbenzoic acid (OSB), have been analyzed for enzymatic defects. Complementation analysis of cell-free extracts of the mutants revealed that there are two groups, as already indicated by genetic analysis. The missing enzyme in each group was identified by complementation of the cell-free extracts with o-succinylbenzoyl-coenzyme A (CoA) synthetase and dihydroxynaphthoate synthase extracted from Mycobacterium phlei. Mutants found to lack dihydroxynaphthoate synthase, and which therefore complement with dihydroxynaphthoate synthase of M. phlei, were designated as menB; those lacking o-succinylbenzoyl-CoA synthetase, and therefore complementing with o-succinylbenzoyl-CoA synthetase, were designated as menE. The menB mutants RB413 (men-325) and RB415 (men-329), when incubated with [2,3-14C2]OSB, produced only the spirodilactone form of OSB in a reaction that was CoA and adenosine 5'-triphosphate dependent. PMID:6780515

Selenium Potentiates Chemotherapeutic Selectivity: Improving Efficacy and Reducing Toxicity

DTIC Science & Technology

2008-04-01

C., et al., Genetic correction of DNA repair-deficient/cancer- prone xeroderma pigmentosum group C keratinocytes. Hum Gene Ther, 2003. 14(10): p...983-96. 4. Muotri, A.R., et al., Complementation of the DNA repair deficiency in human xeroderma pigmentosum group a and C cells by recombinant...survival Keywords: DNA-repair, carboplatin, cisplatin, myelosuppression Abbreviations: Xpc, protein encoded by the xeroderma pigmentosum XPC

Genetic analysis of indefinite division in human cells: Evidence for a cell senescence-related gene(s) on human chromosome 4

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yi Ning; Ledbetter, D.H.; Smith, J.R.

1991-07-01

Earlier studies had demonstrated that fusion of normal with immortal human cells yielded hybrids having limited division potential. This indicated that the phenotype of limited proliferation (cellular senescence) is dominant and that immortal cells result from recessive changes in normal growth-regulatory genes. In additional studies, the authors exploited the fact that the immortal phenotype is recessive and, by fusing various immortal human cell lines with each other, identified four complementation groups for indefinite division. Assignment of cell lines to specific groups allowed us to take a focused approach to identify the chromosomes and genes involved in growth regulation that havemore » been modified in immortal cells. They report here that introduction of a normal human chromosome 4 into three immortal cell lines (HeLa, J82, T98G) assigned to complementation group B resulted in loss of proliferation and reversal of the immortal phenotype. No effect on the proliferation potential of cell lines representative of the other complementation groups was observed. This result suggests that a gene(s) involved in cellular senescence and normal growth regulation resides on chromosome 4.« less

Linkage analysis of the Fanconi anemia gene FACC with chromosome 9q markers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Auerbach, A.D.; Shin, H.T.; Kaporis, A.G.

1994-09-01

Fanconi anemia (FA) is a genetically heterogeneous syndrome, with at least four different complementation groups as determined by cell fusion studies. The gene for complementation group C, FACC, has been cloned and mapped to chromosome 9q22.3 by in situ hybridization, while linkage analysis has supported the placement of another gene on chromosome 20q. We have analyzed five microsatellite markers and one RFLP on chromosome 9q in a panel of FA families from the International Fanconi Anemia Registry (IFAR) in order to place FACC on the genetic map. Polymorphisms were typed in 308 individuals from 51 families. FACC is tightly linkedmore » to both D9S151 [{Theta}{sub max}=0.025, Z{sub max}=7.75] and to D9S196 [{Theta}{sub max}=0.041, Z{sub max}=7.89]; multipoint analysis is in progress. We are currently screening a YAC clone that contains the entire FACC gene for additional microsatellite markers suitable for haplotype analysis of FA families.« less

Complementation and Genetic Recombination in Candida lipolytica

PubMed Central

Bassel, John; Warfei, Jean; Mortimer, Robert

1971-01-01

Nutritional requirements were introduced into wild-type, heterothallic strains of Candida lipolytica by exposing the cells to X rays. Complementing hybrids were recovered from mixtures of the auxotrophic strains, and genetic recombination was observed in individually isolated ascospores from the hybrid strains. PMID:5122814

Lack of association of CFD polymorphisms with advanced age-related macular degeneration.

PubMed

Zeng, Jiexi; Chen, Yuhong; Tong, Zongzhong; Zhou, Xinrong; Zhao, Chao; Wang, Kevin; Hughes, Guy; Kasuga, Daniel; Bedell, Matthew; Lee, Clara; Ferreyra, Henry; Kozak, Igor; Haw, Weldon; Guan, Jean; Shaw, Robert; Stevenson, William; Weishaar, Paul D; Nelson, Mark H; Tang, Luosheng; Zhang, Kang

2010-11-03

Age-related macular degeneration (AMD) is the most common cause of irreversible central vision loss worldwide. Research has linked AMD susceptibility with dysregulation of the complement cascade. Typically, complement factor H (CFH), complement factor B (CFB), complement component 2 (C2), and complement component 3 (C3) are associated with AMD. In this paper, we investigated the association between complement factor D (CFD), another factor of the complement system, and advanced AMD in a Caucasian population. Six single nucleotide polymorphisms (SNPs), rs1683564, rs35186399, rs1683563, rs3826945, rs34337649, and rs1651896, across the region covering CFD, were chosen for this study. One hundred and seventy-eight patients with advanced AMD and 161 age-matched normal controls were genotyped. Potential positive signals were further tested in another independent 445 advanced AMD patients and 190 controls. χ2 tests were performed to compare the allele frequencies between case and control groups. None of the six SNPs of CFD was found to be significantly associated with advanced AMD in our study. Our findings suggest that CFD may not play a major role in the genetic susceptibility to AMD because no association was found between the six SNPs analyzed in the CFD region and advanced AMD.

Association of complementation group and mutation type with clinical outcome in fanconi anemia. European Fanconi Anemia Research Group.

PubMed

Faivre, L; Guardiola, P; Lewis, C; Dokal, I; Ebell, W; Zatterale, A; Altay, C; Poole, J; Stones, D; Kwee, M L; van Weel-Sipman, M; Havenga, C; Morgan, N; de Winter, J; Digweed, M; Savoia, A; Pronk, J; de Ravel, T; Jansen, S; Joenje, H; Gluckman, E; Mathew, C G

2000-12-15

Fanconi anemia (FA) is a clinically and genetically heterogeneous disorder. Clinical care is complicated by variable age at onset and severity of hematologic symptoms. Recent advances in the molecular biology of FA have allowed us to investigate the relationship between FA genotype and the nature and severity of the clinical phenotype. Two hundred forty-five patients from all 7 known complementation groups (FA-A to FA-G) were studied. Mutations were detected in one of the cloned FANC genes in 169 patients; in the remainder the complementation group was assigned by cell fusion or Western blotting. A range of qualitative and quantitative clinical parameters was compared for each complementation group and for different classes of mutation. Significant phenotypic differences were found. FA-G patients had more severe cytopenia and a higher incidence of leukemia. Somatic abnormalities were less prevalent in FA-C, but more common in the rare groups FA-D, FA-E, and FA-F. In FA-A, patients homozygous for null mutations had an earlier onset of anemia and a higher incidence of leukemia than those with mutations producing an altered protein. In FA-C, there was a later age of onset of aplastic anemia and fewer somatic abnormalities in patients with the 322delG mutation, but there were more somatic abnormalities in patients with IVS4 + 4A --> T. This study indicates that FA patients with mutations in the FANCG gene and patients homozygous for null mutations in FANCA are high-risk groups with a poor hematologic outcome and should be considered as candidates both for frequent monitoring and early therapeutic intervention. (Blood. 2000;96:4064-4070)

X-ray cross-complementing groups 1 rs1799782 C>T polymorphisms and colorectal cancer susceptibility: A meta-analysis based on Chinese Han population.

PubMed

Wang, Liming; Qian, Junfeng; Ying, Chunxiao; Zhuang, Yongwei; Shang, Xingjie; Xu, Fang

2016-12-01

X-ray cross-complementing groups 1 (XRCC1) rs1799782 C>T polymorphisms and colorectal cancer susceptibility were not clear. The purpose of this study was to evaluate the association between XRCC1 rs1799782 C>T polymorphisms and colorectal cancer susceptibility by meta-analysis. Related databases of Medline, CNKI, and Wanfang were systematic searched for the studies related to XRCC1 rs1799782 C>T polymorphisms and colorectal cancer risk in Chinese Han population. The genotype distribution of CC, CT and TT were extracted from each included studies in the colorectal cancer patients and healthy control subjects. The odds ratio (OR) and its 95% confidence interval (95% CI) was used to assess the correlation between genetype and colorectal cancer risk. The publications for this study was evaluated by Begg's funnel plot and Egger's line regression test. The median frequency of CC, CT, and TT genotype in cancer group were 48%, 41% and 11%; For control group, they were 51%, 40% and 8%; the pooled results showed that OR = 1.32 (95% CI: 1.041-1.67, P < 0.05). The pooled results indicated that XRCC1 rs1799782 C>T polymorphisms was associated with colorectal cancer susceptibility in recessive genetic model OR = 1.32 (95% CI: 1.041-1.67, P < 0.05), dominant genetic model OR = 1.21 (95% CI: 1.00-1.46, P < 0.05) and homozygous genetic model OR = 1.43 (95% CI: 1.07-1.91, P < 0.05). The funnel plot was significant asymmetric at the bottom and the Egger's test also indicated significant publication bias (t = 2.43, P = 0.04) for recessive genetic model. But, no publication bias was found in dominant and homozygous model (P > 0.05). Chinese Han people with rs1799782 TT/CT genotype of XRCC1 gene may have increased risk of developing colorectal.

Novel roles of complement in renal diseases and their therapeutic consequences.

PubMed

Wada, Takehiko; Nangaku, Masaomi

2013-09-01

The complement system functions as a part of the innate immune system. Inappropriate activation of the complement pathways has a deleterious effect on kidneys. Recent advances in complement research have provided new insights into the pathogenesis of glomerular and tubulointerstitial injury associated with complement activation. A new disease entity termed 'C3 glomerulopathy' has recently been proposed and is characterized by isolated C3 deposition in glomeruli without positive staining for immunoglobulins. Genetic and functional studies have demonstrated that several different mutations and disease variants, as well as the generation of autoantibodies, are potentially associated with its pathogenesis. The data from comprehensive analyses suggest that complement dysregulation can also be associated with hemolytic uremic syndrome and more common glomerular diseases, such as IgA nephropathy and diabetic kidney disease. In addition, animal studies utilizing genetically modified mice have begun to elucidate the molecular pathomechanisms associated with the complement system. From a diagnostic point of view, a noninvasive, MRI-based method for detecting C3 has recently been developed to serve as a novel tool for diagnosing complement-mediated kidney diseases. While novel therapeutic tools related to complement regulation are emerging, studies evaluating the precise roles of the complement system in kidney diseases will still be useful for developing new therapeutic approaches.

THE PATHOPHYSIOLOGY OF GEOGRAPHIC ATROPHY SECONDARY TO AGE-RELATED MACULAR DEGENERATION AND THE COMPLEMENT PATHWAY AS A THERAPEUTIC TARGET

PubMed Central

Schmidt-Erfurth, Ursula; van Lookeren Campagne, Menno; Henry, Erin C.; Brittain, Christopher

2017-01-01

Purpose: Geographic atrophy (GA) is an advanced, vision-threatening form of age-related macular degeneration (AMD) affecting approximately five million individuals worldwide. To date, there are no approved therapeutics for GA treatment; however, several are in clinical trials. This review focuses on the pathophysiology of GA, particularly the role of complement cascade dysregulation and emerging therapies targeting the complement cascade. Methods: Primary literature search on PubMed for GA, complement cascade in age-related macular degeneration. ClinicalTrials.gov was searched for natural history studies in GA and clinical trials of drugs targeting the complement cascade for GA. Results: Cumulative damage to the retina by aging, environmental stress, and other factors triggers inflammation via multiple pathways, including the complement cascade. When regulatory components in these pathways are compromised, as with several GA-linked genetic risk factors in the complement cascade, chronic inflammation can ultimately lead to the retinal cell death characteristic of GA. Complement inhibition has been identified as a key candidate for therapeutic intervention, and drugs targeting the complement pathway are currently in clinical trials. Conclusion: The complement cascade is a strategic target for GA therapy. Further research, including on natural history and genetics, is crucial to expand the understanding of GA pathophysiology and identify effective therapeutic targets. PMID:27902638

Genetic analysis of biodegradation of tetralin by a Sphingomonas strain

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hernaez, M.J.; Santero, E.; Reineke, W.

Tetralin (1,2,3,4-tetrahydronaphthalene) is produced for industrial purposes from naphthalene by catalytic hydrogenation or from anthracene by cracking. A strain designated TFA which very efficiently utilizes tetralin has been isolated from the Rhine river. The strain has been identified as Sphingomonas macrogoltabidus, based on 16S rDNA sequence similarity. Genetic analysis of tetralin biodegradation has been performed by insertion mutagenesis and by physical analysis and analysis of complementation between the mutants. The genes involved in tetralin utilization are clustered in a region of 9 kb, comprising at least five genes grouped in two divergently transcribed operons.

Classical and alternative complement activation on photoreceptor outer segments drives monocyte-dependent retinal atrophy.

PubMed

Katschke, Kenneth J; Xi, Hongkang; Cox, Christian; Truong, Tom; Malato, Yann; Lee, Wyne P; McKenzie, Brent; Arceo, Rommel; Tao, Jianhua; Rangell, Linda; Reichelt, Mike; Diehl, Lauri; Elstrott, Justin; Weimer, Robby M; Campagne, Menno van Lookeren

2018-05-09

Geographic atrophy (GA), the advanced form of dry age-related macular degeneration (AMD), is characterized by progressive loss of retinal pigment epithelium cells and photoreceptors in the setting of characteristic extracellular deposits and remains a serious unmet medical need. While genetic predisposition to AMD is dominated by polymorphisms in complement genes, it remains unclear how complement activation contributes to retinal atrophy. Here we demonstrate that complement is activated on photoreceptor outer segments (POS) in the retina peripheral to atrophic lesions associated with GA. When exposed to human serum following outer blood-retinal barrier breakdown, POS act as potent activators of the classical and alternative complement pathway. In mouse models of retinal degeneration, classical and alternative pathway complement activation on photoreceptors contributed to the loss of photoreceptor function. This was dependent on C5a-mediated recruitment of peripheral blood monocytes but independent of resident microglia. Genetic or pharmacologic inhibition of both classical and alternative complement C3 and C5 convertases was required to reduce progressive degeneration of photoreceptor rods and cones. Our study implicates systemic classical and alternative complement proteins and peripheral blood monocytes as critical effectors of localized retinal degeneration with potential relevance for the contribution of complement activation to GA.

Mouse genetics and proteomic analyses demonstrate a critical role for complement in a model of DHRD/ML, an inherited macular degeneration

PubMed Central

Garland, Donita L.; Fernandez-Godino, Rosario; Kaur, Inderjeet; Speicher, Kaye D.; Harnly, James M.; Lambris, John D.; Speicher, David W.; Pierce, Eric A.

2014-01-01

Macular degenerations, inherited and age related, are important causes of vision loss. Human genetic studies have suggested perturbation of the complement system is important in the pathogenesis of age-related macular degeneration. The mechanisms underlying the involvement of the complement system are not understood, although complement and inflammation have been implicated in drusen formation. Drusen are an early clinical hallmark of inherited and age-related forms of macular degeneration. We studied one of the earliest stages of macular degeneration which precedes and leads to the formation of drusen, i.e. the formation of basal deposits. The studies were done using a mouse model of the inherited macular dystrophy Doyne Honeycomb Retinal Dystrophy/Malattia Leventinese (DHRD/ML) which is caused by a p.Arg345Trp mutation in EFEMP1. The hallmark of DHRD/ML is the formation of drusen at an early age, and gene targeted Efemp1R345W/R345W mice develop extensive basal deposits. Proteomic analyses of Bruch's membrane/choroid and Bruch's membrane in the Efemp1R345W/R345W mice indicate that the basal deposits comprise normal extracellular matrix (ECM) components present in abnormal amounts. The proteomic analyses also identified significant changes in proteins with immune-related function, including complement components, in the diseased tissue samples. Genetic ablation of the complement response via generation of Efemp1R345W/R345W:C3−/− double-mutant mice inhibited the formation of basal deposits. The results demonstrate a critical role for the complement system in basal deposit formation, and suggest that complement-mediated recognition of abnormal ECM may participate in basal deposit formation in DHRD/ML and perhaps other macular degenerations. PMID:23943789

A Genetic Analysis of the Suppressor 2 of Zeste Complex of Drosophila Melanogaster

PubMed Central

Wu, C. T.; Howe, M.

1995-01-01

The zeste(1) (z(1)) mutation of Drosophila melanogaster produces a mutant yellow eye color instead of the wild-type red. Genetic and molecular data suggest that z(1) achieves this change by altering expression of the wild-type white gene in a manner that exhibits transvection effects. There exist suppressor and enhancer mutations that modify the z(1) eye color, and this paper summarizes our studies of those belonging to the Suppressor 2 of zeste complex [Su(z)2-C]. The Su(z)2-C consists of at least three subregions called Psc (Posterior sex combs), Su(z)2 and Su(z)2D (Distal). The products of these subregions are proposed to act at the level of chromatin. Complementation analyses predict that the products are functionally similar and interacting. The alleles of Psc define two overlapping phenotypic classes, the hopeful and hapless. The distinctions between these two classes and the intragenic complementation seen among some of the Psc alleles are consistent with a multidomain structure for the product of Psc. Psc is a member of the homeotic Polycomb group of genes. A general discussion of the Polycomb and trithorax group of genes, position-effect variegation, transvection, chromosome pairing and chromatin structure is presented. PMID:7635282

Genetic diversity of popcorn genotypes using molecular analysis.

PubMed

Resh, F S; Scapim, C A; Mangolin, C A; Machado, M F P S; do Amaral, A T; Ramos, H C C; Vivas, M

2015-08-19

In this study, we analyzed dominant molecular markers to estimate the genetic divergence of 26 popcorn genotypes and evaluate whether using various dissimilarity coefficients with these dominant markers influences the results of cluster analysis. Fifteen random amplification of polymorphic DNA primers produced 157 amplified fragments, of which 65 were monomorphic and 92 were polymorphic. To calculate the genetic distances among the 26 genotypes, the complements of the Jaccard, Dice, and Rogers and Tanimoto similarity coefficients were used. A matrix of Dij values (dissimilarity matrix) was constructed, from which the genetic distances among genotypes were represented in a more simplified manner as a dendrogram generated using the unweighted pair-group method with arithmetic average. Clusters determined by molecular analysis generally did not group material from the same parental origin together. The largest genetic distance was between varieties 17 (UNB-2) and 18 (PA-091). In the identification of genotypes with the smallest genetic distance, the 3 coefficients showed no agreement. The 3 dissimilarity coefficients showed no major differences among their grouping patterns because agreement in determining the genotypes with large, medium, and small genetic distances was high. The largest genetic distances were observed for the Rogers and Tanimoto dissimilarity coefficient (0.74), followed by the Jaccard coefficient (0.65) and the Dice coefficient (0.48). The 3 coefficients showed similar estimations for the cophenetic correlation coefficient. Correlations among the matrices generated using the 3 coefficients were positive and had high magnitudes, reflecting strong agreement among the results obtained using the 3 evaluated dissimilarity coefficients.

Evaluation of serum levels of C3 and C4 complement factors in patients with beta thalassemia major in Khuzestan Province, Southwest Iran.

PubMed

Ghafourian, Mehri; Esmaeili, Mehrnosh; Dashti-Gerdabi, Nader; Sadeghi, Alireza; Malekei Naseri, Ali; Kazemi, Akhtar

2017-01-01

Thalassemia syndrome is the most common genetic disorder in the world and infection is the second cause of death in these patients. Measurement of serum C3 and C4 complement factors in serum was done in 60 patients with beta thalassemia major in comparison with 30 healthy subjects as control group. The serum level of C3 and C4 complement factors in 60 patients with beta thalassemia major who were randomly selected from among the patients referred to Shafa Hospital of Ahvaz was evaluated and compared with 30 samples from healthy individuals with no history of recent infectious or autoimmune diseases. It should be noted that single-radial-immunodiffusion assay was used in this study. This study has shown a significant reduction in serum levels of C3 and C4 in patients compared to controls (P value < 0.05). Decreased synthesis or increased consumption of complement factors in patients receiving multiple blood transfusions might lead to continuous contact between the immune system and various antigens, causing nonstop use of complement factors, recurrent infections, changes in parameters of the immune system due to iron overload as well as exposure to infectious factors such as HBV, HCV, HIV, and HTLV through blood transfusion.

Complement pathway biomarkers and age-related macular degeneration

PubMed Central

Gemenetzi, M; Lotery, A J

2016-01-01

In the age-related macular degeneration (AMD) ‘inflammation model', local inflammation plus complement activation contributes to the pathogenesis and progression of the disease. Multiple genetic associations have now been established correlating the risk of development or progression of AMD. Stratifying patients by their AMD genetic profile may facilitate future AMD therapeutic trials resulting in meaningful clinical trial end points with smaller sample sizes and study duration. PMID:26493033

Genetic variation in CFH predicts phenytoin-induced maculopapular exanthema in European-descent patients

PubMed Central

McCormack, Mark; Gui, Hongsheng; Ingason, Andrés; Speed, Doug; Wright, Galen E.B.; Zhang, Eunice J.; Secolin, Rodrigo; Yasuda, Clarissa; Kwok, Maxwell; Wolking, Stefan; Becker, Felicitas; Rau, Sarah; Avbersek, Andreja; Heggeli, Kristin; Leu, Costin; Depondt, Chantal; Sills, Graeme J.; Marson, Anthony G.; Auce, Pauls; Brodie, Martin J.; Francis, Ben; Johnson, Michael R.; Koeleman, Bobby P.C.; Striano, Pasquale; Coppola, Antonietta; Zara, Federico; Kunz, Wolfram S.; Sander, Josemir W.; Lerche, Holger; Klein, Karl Martin; Weckhuysen, Sarah; Krenn, Martin; Gudmundsson, Lárus J.; Stefánsson, Kári; Krause, Roland; Shear, Neil; Ross, Colin J.D.; Delanty, Norman; Pirmohamed, Munir; Carleton, Bruce C.; Cendes, Fernando; Lopes-Cendes, Iscia; Liao, Wei-ping; O'Brien, Terence J.; Sisodiya, Sanjay M.; Cherny, Stacey; Kwan, Patrick; Baum, Larry

2018-01-01

Objective To characterize, among European and Han Chinese populations, the genetic predictors of maculopapular exanthema (MPE), a cutaneous adverse drug reaction common to antiepileptic drugs. Methods We conducted a case-control genome-wide association study of autosomal genotypes, including Class I and II human leukocyte antigen (HLA) alleles, in 323 cases and 1,321 drug-tolerant controls from epilepsy cohorts of northern European and Han Chinese descent. Results from each cohort were meta-analyzed. Results We report an association between a rare variant in the complement factor H–related 4 (CFHR4) gene and phenytoin-induced MPE in Europeans (p = 4.5 × 10–11; odds ratio [95% confidence interval] 7 [3.2–16]). This variant is in complete linkage disequilibrium with a missense variant (N1050Y) in the complement factor H (CFH) gene. In addition, our results reinforce the association between HLA-A*31:01 and carbamazepine hypersensitivity. We did not identify significant genetic associations with MPE among Han Chinese patients. Conclusions The identification of genetic predictors of MPE in CFHR4 and CFH, members of the complement factor H–related protein family, suggest a new link between regulation of the complement system alternative pathway and phenytoin-induced hypersensitivity in European-ancestral patients. PMID:29288229

Xeroderma pigmentosum: biochemical and genetic characteristics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cleaver, J.E.; Bootsma, D.

1975-01-01

Biochemical and genetic studies on xeroderma pigmentosum are reviewed under the following headings: clinical features of xeroderma pigmentosum; karyotype; cell killing and host cell reactivation after irradiation or exposure to chemical carcinogens; SV40 transformation of xeroderma pigmentosum cells; biochemical defects in the common and de Sanctis-Cacchione forms of xeroderma pigmentosum; cell hybridization and complementation groups; biochemical defects in the xeroderma pigmentosum variant and the role of caffeine in DNA repair; DNA repair in xeroderma pigmentosum heterozygotes; response of xeroderma pigmentosum cells to various mutagens and chemical carcinogens; other high and low repair diseases; and possible significance of DNA repair inmore » theories of aging and carcinogenesis. (HLW)« less

P-Element Insertion Alleles of Essential Genes on the Third Chromosome of Drosophila Melanogaster: Correlation of Physical and Cytogenetic Maps in Chromosomal Region 86e-87f

PubMed Central

Deak, P.; Omar, M. M.; Saunders, RDC.; Pal, M.; Komonyi, O.; Szidonya, J.; Maroy, P.; Zhang, Y.; Ashburner, M.; Benos, P.; Savakis, C.; Siden-Kiamos, I.; Louis, C.; Bolshakov, V. N.; Kafatos, F. C.; Madueno, E.; Modolell, J.; Glover, D. M.

1997-01-01

We have established a collection of 2460 lethal or semi-lethal mutant lines using a procedure thought to insert single P elements into vital genes on the third chromosome of Drosophila melanogaster. More than 1200 randomly selected lines were examined by in situ hybridization and 90% found to contain single insertions at sites that mark 89% of all lettered subdivisions of the Bridges' map. A set of chromosomal deficiencies that collectively uncover ~25% of the euchromatin of chromosome 3 reveal lethal mutations in 468 lines corresponding to 145 complementation groups. We undertook a detailed analysis of the cytogenetic interval 86E-87F and identified 87 P-element-induced mutations falling into 38 complementation groups, 16 of which correspond to previously known genes. Twenty-one of these 38 complementation groups have at least one allele that has a P-element insertion at a position consistent with the cytogenetics of the locus. We have rescued P elements and flanking chromosomal sequences from the 86E-87F region in 35 lines with either lethal or genetically silent P insertions, and used these as probes to identify cosmids and P1 clones from the Drosophila genome projects. This has tied together the physical and genetic maps and has linked 44 previously identified cosmid contigs into seven ``supercontigs'' that span the interval. STS data for sequences flanking one side of the P-element insertions in 49 lines has identified insertions in the αγ element at 87C, two known transposable elements, and the open reading frames of seven putative single copy genes. These correspond to five known genes in this interval, and two genes identified by the homology of their predicted products to known proteins from other organisms. PMID:9409831

Morphoagronomic and molecular profiling of Capsicum spp from southwest Mato Grosso, Brazil.

PubMed

Campos, A L; Marostega, T N; Cabral, N S S; Araújo, K L; Serafim, M E; Seabra-Júnior, S; Sudré, C P; Rodrigues, R; Neves, L G

2016-07-15

The genus Capsicum ranks as the second most exported vegetable in Brazil, which is also considered to be a center of diversity for this genus. The aim of this study was to rescue genetic variability in the genus Capsicum in the southwest region of Mato Grosso, and to characterize and estimate the genetic diversity of accessions based on morphoagronomic descriptors and inter-simple sequence repeat molecular markers. Data were obtained following the criteria of the International Plant Genetic Resources Institute, renamed Bioversity International for Capsicum. Data were analyzed using different multivariate statistical techniques. An array of binary data was used to analyze molecular data, and the arithmetic complement of the Jaccard index was used to estimate the genetic dissimilarity among accessions. Six well-defined groups were formed based on the morphological characterization. The most divergent accessions were 142 and 126, with 125 and 126 being the most similar. The groups formed following agronomic characterization differed from those formed by morphological characterization, and there was a need to subdivide the groups for better distinction of accessions. Based on molecular analysis, accessions were divided into two groups, and there was also a need to subdivide the groups. Based on joint analysis (morphological + agronomic + molecular), six groups were formed with no duplicates. For all groups, the cophenetic correlation coefficient was higher than 0.8. These results provide useful information for the better management of the work collection. All correlations between the combined distance matrix were significant by the Mantel test.

Genetics Home Reference: complement component 8 deficiency

MedlinePlus

... in people with Hispanic, Japanese, or African Caribbean heritage, whereas type II primarily occurs in people of Northern European descent. Related Information What information about a genetic condition can statistics provide? Why are some genetic ...

Functional analyses of rare genetic variants in complement component C9 identified in patients with age-related macular degeneration.

PubMed

Kremlitzka, Mariann; Geerlings, Maartje J; de Jong, Sarah; Bakker, Bjorn; Nilsson, Sara C; Fauser, Sascha; Hoyng, Carel B; de Jong, Eiko K; den Hollander, Anneke I; Blom, Anna M

2018-05-14

Age-related macular degeneration (AMD) is a progressive disease of the central retina and the leading cause of irreversible vision loss in the western world. The involvement of abnormal complement activation in AMD has been suggested by association of variants in genes encoding complement proteins with disease development. A low-frequency variant (p.P167S) in the complement component C9 (C9) gene was recently shown to be highly associated with AMD, however its functional outcome remains largely unexplored. In this study, we reveal five novel rare genetic variants (p.M45L, p.F62S, p.G126R, p.T170I and p.A529T) in C9 in AMD patients, and evaluate their functional effects in vitro together with the previously identified (p.R118W and p.P167S) C9 variants.Our results demonstrate that the concentration of C9 is significantly elevated in patients' sera carrying the p.M45L, p.F62S, p.P167S and p.A529T variants compared to non-carrier controls. However, no difference can be observed in soluble terminal complement complex levels between the carrier and non-carrier groups. Comparing the polymerization of the C9 variants we reveal that the p.P167S mutant spontaneously aggregates, while the other mutant proteins (except for C9 p.A529T) fail to polymerize in the presence of zinc. Altered polymerization of the p.F62S and p.P167S proteins associated with decreased lysis of sheep erythrocytes and ARPE-19 cells by carriers' sera. Our data suggest that the analysed C9 variants affect only the secretion and polymerization of C9, without influencing its classical lytic activity. Future studies need to be performed to understand the implications of the altered polymerization of C9 in AMD pathology.

The first genetic map of a synthesized allohexaploid Brassica with A, B and C genomes based on simple sequence repeat markers.

PubMed

Yang, S; Chen, S; Geng, X X; Yan, G; Li, Z Y; Meng, J L; Cowling, W A; Zhou, W J

2016-04-01

We present the first genetic map of an allohexaploid Brassica species, based on segregating microsatellite markers in a doubled haploid mapping population generated from a hybrid between two hexaploid parents. This study reports the first genetic map of trigenomic Brassica. A doubled haploid mapping population consisting of 189 lines was obtained via microspore culture from a hybrid H16-1 derived from a cross between two allohexaploid Brassica lines (7H170-1 and Y54-2). Simple sequence repeat primer pairs specific to the A genome (107), B genome (44) and C genome (109) were used to construct a genetic linkage map of the population. Twenty-seven linkage groups were resolved from 274 polymorphic loci on the A genome (109), B genome (49) and C genome (116) covering a total genetic distance of 3178.8 cM with an average distance between markers of 11.60 cM. This is the first genetic framework map for the artificially synthesized Brassica allohexaploids. The linkage groups represent the expected complement of chromosomes in the A, B and C genomes from the original diploid and tetraploid parents. This framework linkage map will be valuable for QTL analysis and future genetic improvement of a new allohexaploid Brassica species, and in improving our understanding of the genetic control of meiosis in new polyploids.

Identification of a central role for complement in osteoarthritis

PubMed Central

Wang, Qian; Rozelle, Andrew L.; Lepus, Christin M.; Scanzello, Carla R.; Song, Jason J.; Larsen, D. Meegan; Crish, James F.; Bebek, Gurkan; Ritter, Susan Y.; Lindstrom, Tamsin M.; Hwang, Inyong; Wong, Heidi H.; Punzi, Leonardo; Encarnacion, Angelo; Shamloo, Mehrdad; Goodman, Stuart B.; Wyss-Coray, Tony; Goldring, Steven R.; Banda, Nirmal K.; Thurman, Joshua M.; Gobezie, Reuben; Crow, Mary K.; Holers, V. Michael; Lee, David M.; Robinson, William H.

2011-01-01

Osteoarthritis, characterized by the breakdown of articular cartilage in synovial joints, has long been viewed as the result of “wear and tear”1. Although low-grade inflammation is detected in osteoarthritis, its role is unclear2–4. Here we identify a central role for the inflammatory complement system in the pathogenesis of osteoarthritis. Through proteomic and transcriptomic analyses of synovial fluids and membranes from individuals with osteoarthritis, we find that expression and activation of complement is abnormally high in human osteoarthritic joints. Using mice genetically deficient in C5, C6, or CD59a, we show that complement, and specifically the membrane attack complex (MAC)-mediated arm of complement, is critical to the development of arthritis in three different mouse models of osteoarthritis. Pharmacological modulation of complement in wild-type mice confirmed the results obtained with genetically deficient mice. Expression of inflammatory and degradative molecules was lower in chondrocytes from destabilized joints of C5-deficient mice than C5-sufficient mice, and MAC induced production of these molecules in cultured chondrocytes. Furthermore, MAC co-localized with matrix metalloprotease (MMP)-13 and with activated extracellular signal-regulated kinase (ERK) around chondrocytes in human osteoarthritic cartilage. Our findings indicate that dysregulation of complement in synovial joints plays a critical role in the pathogenesis of osteoarthritis. PMID:22057346

Can innate and autoimmune reactivity forecast early and advance stages of age-related macular degeneration?

PubMed

Adamus, Grazyna

2017-03-01

Age-related macular degeneration (AMD) is a major cause of central vision loss in persons over 55years of age in developed countries. AMD is a complex disease in which genetic, environmental and inflammatory factors influence its onset and progression. Elevation in serum anti-retinal autoantibodies, plasma and local activation of complement proteins of the alternative pathway, and increase in secretion of proinflammatory cytokines have been seen over the course of disease. Genetic studies of AMD patients confirmed that genetic variants affecting the alternative complement pathway have a major influence on AMD risk. Because the heterogeneity of this disease, there is no sufficient strategy to identify the disease onset and progression sole based eye examination, thus identification of reliable serological biomarkers for diagnosis, prognosis and response to treatment by sampling patient's blood is necessary. This review provides an outline of the current knowledge on possible serological (autoantibodies, complement factors, cytokines, chemokines) and related genetic biomarkers relevant to the pathology of AMD, and discusses their application for prediction of disease activity and prognosis in AMD. Copyright © 2017 Elsevier B.V. All rights reserved.

Genetic variation in CFH predicts phenytoin-induced maculopapular exanthema in European-descent patients.

PubMed

McCormack, Mark; Gui, Hongsheng; Ingason, Andrés; Speed, Doug; Wright, Galen E B; Zhang, Eunice J; Secolin, Rodrigo; Yasuda, Clarissa; Kwok, Maxwell; Wolking, Stefan; Becker, Felicitas; Rau, Sarah; Avbersek, Andreja; Heggeli, Kristin; Leu, Costin; Depondt, Chantal; Sills, Graeme J; Marson, Anthony G; Auce, Pauls; Brodie, Martin J; Francis, Ben; Johnson, Michael R; Koeleman, Bobby P C; Striano, Pasquale; Coppola, Antonietta; Zara, Federico; Kunz, Wolfram S; Sander, Josemir W; Lerche, Holger; Klein, Karl Martin; Weckhuysen, Sarah; Krenn, Martin; Gudmundsson, Lárus J; Stefánsson, Kári; Krause, Roland; Shear, Neil; Ross, Colin J D; Delanty, Norman; Pirmohamed, Munir; Carleton, Bruce C; Cendes, Fernando; Lopes-Cendes, Iscia; Liao, Wei-Ping; O'Brien, Terence J; Sisodiya, Sanjay M; Cherny, Stacey; Kwan, Patrick; Baum, Larry; Cavalleri, Gianpiero L

2018-01-23

To characterize, among European and Han Chinese populations, the genetic predictors of maculopapular exanthema (MPE), a cutaneous adverse drug reaction common to antiepileptic drugs. We conducted a case-control genome-wide association study of autosomal genotypes, including Class I and II human leukocyte antigen (HLA) alleles, in 323 cases and 1,321 drug-tolerant controls from epilepsy cohorts of northern European and Han Chinese descent. Results from each cohort were meta-analyzed. We report an association between a rare variant in the complement factor H-related 4 ( CFHR4 ) gene and phenytoin-induced MPE in Europeans ( p = 4.5 × 10 -11 ; odds ratio [95% confidence interval] 7 [3.2-16]). This variant is in complete linkage disequilibrium with a missense variant (N1050Y) in the complement factor H ( CFH ) gene. In addition, our results reinforce the association between HLA-A*31:01 and carbamazepine hypersensitivity. We did not identify significant genetic associations with MPE among Han Chinese patients. The identification of genetic predictors of MPE in CFHR4 and CFH, members of the complement factor H-related protein family, suggest a new link between regulation of the complement system alternative pathway and phenytoin-induced hypersensitivity in European-ancestral patients. Copyright © 2017 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Neurology.

Serological and Genetic Evidence for Altered Complement System Functionality in Systemic Lupus Erythematosus: Findings of the GAPAID Consortium.

PubMed

Prechl, József; Papp, Krisztián; Hérincs, Zoltán; Péterfy, Hajna; Lóránd, Veronika; Szittner, Zoltán; Estonba, Andone; Rovero, Paolo; Paolini, Ilaria; Del Amo, Jokin; Uribarri, Maria; Alcaro, Maria Claudia; Ruiz-Larrañaga, Otsanda; Migliorini, Paola; Czirják, László

2016-01-01

Systemic lupus erythematosus is a chronic autoimmune disease with multifactorial ethiopathogenesis. The complement system is involved in both the early and late stages of disease development and organ damage. To better understand autoantibody mediated complement consumption we examined ex vivo immune complex formation on autoantigen arrays. We recruited patients with SLE (n = 211), with other systemic autoimmune diseases (n = 65) and non-autoimmune control subjects (n = 149). Standard clinical and laboratory data were collected and serum complement levels were determined. The genotype of SNP rs1143679 in the ITGAM gene was also determined. Ex vivo formation of immune complexes, with respect to IgM, IgG, complement C4 and C3 binding, was examined using a functional immunoassay on autoantigen microarray comprising nucleic acids, proteins and lipids. Complement consumption of nucleic acids increased upon binding of IgM and IgG even when serum complement levels were decreased due to consumption in SLE patients. A negative correlation between serum complement levels and ex vivo complement deposition on nucleic acid autoantigens is demonstrated. On the contrary, complement deposition on tested protein and lipid autoantigens showed positive correlation with C4 levels. Genetic analysis revealed that the non-synonymous variant rs1143679 in complement receptor type 3 is associated with an increased production of anti-dsDNA IgG antibodies. Notwithstanding, homozygous carriers of the previously reported susceptible allele (AA) had lower levels of dsDNA specific IgM among SLE patients. Both the non-synonymous variant rs1143679 and the high ratio of nucleic acid specific IgG/IgM were associated with multiple organ involvement. In summary, secondary complement deficiency in SLE does not impair opsonization of nucleic-acid-containing autoantigens but does affect other antigens and potentially other complement dependent processes. Dysfunction of the receptor recognizing complement opsonized immune complexes promotes the development of class-switched autoantibodies targeting nucleic acids.

Smoke Exposure Causes Endoplasmic Reticulum Stress and Lipid Accumulation in Retinal Pigment Epithelium through Oxidative Stress and Complement Activation*

PubMed Central

Kunchithapautham, Kannan; Atkinson, Carl; Rohrer, Bärbel

2014-01-01

Age-related macular degeneration (AMD) is a complex disease caused by genetic and environmental factors, including genetic variants in complement components and smoking. Smoke exposure leads to oxidative stress, complement activation, endoplasmic reticulum (ER) stress, and lipid dysregulation, which have all been proposed to be associated with AMD pathogenesis. Here we examine the effects of smoke exposure on the retinal pigment epithelium (RPE). Mice were exposed to cigarette smoke or filtered air for 6 months. RPE cells grown as stable monolayers were exposed to 5% cigarette smoke extract (CSE). Effects of smoke were determined by biochemical, molecular, and histological measures. Effects of the alternative pathway (AP) of complement and complement C3a anaphylatoxin receptor signaling were analyzed using knock-out mice or specific inhibitors. ER stress markers were elevated after smoke exposure in RPE of intact mice, which was eliminated in AP-deficient mice. To examine this relationship further, RPE monolayers were exposed to CSE. Short term smoke exposure resulted in production and release of complement C3, the generation of C3a, oxidative stress, complement activation on the cell membrane, and ER stress. Long term exposure to CSE resulted in lipid accumulation, and secretion. All measures were reversed by blocking C3a complement receptor (C3aR), alternative complement pathway signaling, and antioxidant therapy. Taken together, our results provide clear evidence that smoke exposure results in oxidative stress and complement activation via the AP, resulting in ER stress-mediated lipid accumulation, and further suggesting that oxidative stress and complement act synergistically in the pathogenesis of AMD. PMID:24711457

A single ataxia telangiectasia gene with a product similar to PI-3 kinase.

PubMed

Savitsky, K; Bar-Shira, A; Gilad, S; Rotman, G; Ziv, Y; Vanagaite, L; Tagle, D A; Smith, S; Uziel, T; Sfez, S; Ashkenazi, M; Pecker, I; Frydman, M; Harnik, R; Patanjali, S R; Simmons, A; Clines, G A; Sartiel, A; Gatti, R A; Chessa, L; Sanal, O; Lavin, M F; Jaspers, N G; Taylor, A M; Arlett, C F; Miki, T; Weissman, S M; Lovett, M; Collins, F S; Shiloh, Y

1995-06-23

A gene, ATM, that is mutated in the autosomal recessive disorder ataxia telangiectasia (AT) was identified by positional cloning on chromosome 11q22-23. AT is characterized by cerebellar degeneration, immunodeficiency, chromosomal instability, cancer predisposition, radiation sensitivity, and cell cycle abnormalities. The disease is genetically heterogeneous, with four complementation groups that have been suspected to represent different genes. ATM, which has a transcript of 12 kilobases, was found to be mutated in AT patients from all complementation groups, indicating that it is probably the sole gene responsible for this disorder. A partial ATM complementary DNA clone of 5.9 kilobases encoded a putative protein that is similar to several yeast and mammalian phosphatidylinositol-3' kinases that are involved in mitogenic signal transduction, meiotic recombination, and cell cycle control. The discovery of ATM should enhance understanding of AT and related syndromes and may allow the identification of AT heterozygotes, who are at increased risk of cancer.

[Polymorphism of genes encoding proteins of DNA repair vs. occupational and environmental exposure to lead, arsenic and pesticides].

PubMed

Bukowski, Karol; Woźniak, Katarzyna

2018-03-09

Genetic polymorphism is associated with the occurrence of at least 2 different alleles in the locus with a frequency higher than 1% in the population. Among polymorphisms we can find single nucleotide polymorphism (SNP) and polymorphism of variable number of tandem repeats. The presence of certain polymorphisms in genes encoding DNA repair enzymes is associated with the speed and efficiency of DNA repair and can protect or expose humans to the effects provoked by xenobiotics. Chemicals, such as lead, arsenic pesticides are considered to exhibit strong toxicity. There are many different polymorphisms in genes encoding DNA repair enzymes, which determine the speed and efficiency of DNA damage repair induced by these xenobiotics. In the case of lead, the influence of various polymorphisms, such as APE1 (apurinic/apyrimidinic endonuclease 1) (rs1130409), hOGG1 (human 8-oxoguanine glycosylase) (rs1052133), XRCC1 (X-ray repair cross-complementing protein group 1) (rs25487), XRCC1 (rs1799782) and XRCC3 (X-ray repair cross-complementing protein group 3) (rs861539) were described. For arsenic polymorphisms, such as ERCC2 (excision repair cross-complementing) (rs13181), XRCC3 (rs861539), APE1 (rs1130409) and hOGG1 (rs1052133) were examined. As to pesticides, separate and combined effects of polymorphisms in genes encoding DNA repair enzymes, such as XRCC1 (rs1799782), hOGG1 (rs1052133), XRCC4 (X-ray repair cross-complementing protein group 4) (rs28360135) and the gene encoding the detoxification enzyme PON1 paraoxonase (rs662) were reported. Med Pr 2018;69(2):225-235. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

AMD and the alternative complement pathway: genetics and functional implications.

PubMed

Tan, Perciliz L; Bowes Rickman, Catherine; Katsanis, Nicholas

2016-06-21

Age-related macular degeneration (AMD) is an ocular neurodegenerative disorder and is the leading cause of legal blindness in Western societies, with a prevalence of up to 8 % over the age of 60, which continues to increase with age. AMD is characterized by the progressive breakdown of the macula (the central region of the retina), resulting in the loss of central vision including visual acuity. While its molecular etiology remains unclear, advances in genetics and genomics have illuminated the genetic architecture of the disease and have generated attractive pathomechanistic hypotheses. Here, we review the genetic architecture of AMD, considering the contribution of both common and rare alleles to susceptibility, and we explore the possible mechanistic links between photoreceptor degeneration and the alternative complement pathway, a cascade that has emerged as the most potent genetic driver of this disorder.

Links between Genetic Groups, Indole Alkaloid Profiles and Ecology within the Grass-Parasitic Claviceps purpurea Species Complex.

PubMed

Negård, Mariell; Uhlig, Silvio; Kauserud, Håvard; Andersen, Tom; Høiland, Klaus; Vrålstad, Trude

2015-04-28

The grass parasitic fungus Claviceps purpurea sensu lato produces sclerotia with toxic indole alkaloids. It constitutes several genetic groups with divergent habitat preferences that recently were delimited into separate proposed species. We aimed to 1) analyze genetic variation of C. purpurea sensu lato in Norway, 2) characterize the associated indole alkaloid profiles, and 3) explore relationships between genetics, alkaloid chemistry and ecology. Approximately 600 sclerotia from 14 different grass species were subjected to various analyses including DNA sequencing and HPLC-MS. Molecular results, supported by chemical and ecological data, revealed one new genetic group (G4) in addition to two of the three known; G1 (C. purpurea sensu stricto) and G2 (C. humidiphila). G3 (C. spartinae) was not found. G4, which was apparently con-specific with the recently described C. arundinis sp. nov, was predominantly found in very wet habitats on Molinia caerulea and infrequently in saline habitats on Leymus arenarius. Its indole-diterpene profile resembled G2, while its ergot alkaloid profile differed from G2 in high amounts of ergosedmam. In contrast to G1, indole-diterpenes were consistently present in G2 and G4. Our study supports and complements the newly proposed species delimitation of the C. purpurea complex, but challenges some species characteristics including host spectrum, habitat preferences and sclerotial floating ability.

Links between Genetic Groups, Indole Alkaloid Profiles and Ecology within the Grass-Parasitic Claviceps purpurea Species Complex

PubMed Central

Negård, Mariell; Uhlig, Silvio; Kauserud, Håvard; Andersen, Tom; Høiland, Klaus; Vrålstad, Trude

2015-01-01

The grass parasitic fungus Claviceps purpurea sensu lato produces sclerotia with toxic indole alkaloids. It constitutes several genetic groups with divergent habitat preferences that recently were delimited into separate proposed species. We aimed to 1) analyze genetic variation of C. purpurea sensu lato in Norway, 2) characterize the associated indole alkaloid profiles, and 3) explore relationships between genetics, alkaloid chemistry and ecology. Approximately 600 sclerotia from 14 different grass species were subjected to various analyses including DNA sequencing and HPLC-MS. Molecular results, supported by chemical and ecological data, revealed one new genetic group (G4) in addition to two of the three known; G1 (C. purpurea sensu stricto) and G2 (C. humidiphila). G3 (C. spartinae) was not found. G4, which was apparently con-specific with the recently described C. arundinis sp. nov, was predominantly found in very wet habitats on Molinia caerulea and infrequently in saline habitats on Leymus arenarius. Its indole-diterpene profile resembled G2, while its ergot alkaloid profile differed from G2 in high amounts of ergosedmam. In contrast to G1, indole-diterpenes were consistently present in G2 and G4. Our study supports and complements the newly proposed species delimitation of the C. purpurea complex, but challenges some species characteristics including host spectrum, habitat preferences and sclerotial floating ability. PMID:25928134

Continuous in vivo infusion of interferon-gamma (IFN-γ) enhances engraftment of syngeneic wild-type cells in Fanca–/– and Fancg–/– mice

PubMed Central

Si, Yue; Ciccone, Samantha; Yang, Feng-Chun; Yuan, Jin; Zeng, Daisy; Chen, Shi; van de Vrugt, Henri J.; Critser, John; Arwert, Fre; Haneline, Laura S.; Clapp, D. Wade

2006-01-01

Fanconi anemia (FA) is a heterogeneous genetic disorder characterized by bone marrow (BM) failure and cancer susceptibility. Identification of the cDNAs of FA complementation types allows the potential of using gene transfer technology to introduce functional cDNAs as transgenes into autologous stem cells and provide a cure for the BM failure in FA patients. However, strategies to enhance the mobilization, transduction, and engraftment of exogenous stem cells are required to optimize efficacy prior to widespread clinical use. Hypersensitivity of Fancc–/– cells to interferon-gamma (IFN-γ), a nongenotoxic immune-regulatory cytokine, enhances engraftment of syngeneic wild-type (WT) cells in Fancc–/– mice. However, whether this phenotype is of broad relevance in other FA complementation groups is unresolved. Here we show that primitive and mature myeloid progenitors in Fanca–/– and Fancg–/– mice are hypersensitive to IFN-γ and that in vivo infusion of IFN-γ at clinically relevant concentrations was sufficient to allow consistent long-term engraftment of isogenic WT repopulating stem cells. Given that FANCA, FANCC, and FANCG complementation groups account for more than 90% of all FA patients, these data provide evidence that IFN-γ conditioning may be a useful nongenotoxic strategy for myelopreparation in FA patients. PMID:16946306

Continuous in vivo infusion of interferon-gamma (IFN-gamma) enhances engraftment of syngeneic wild-type cells in Fanca-/- and Fancg-/- mice.

PubMed

Si, Yue; Ciccone, Samantha; Yang, Feng-Chun; Yuan, Jin; Zeng, Daisy; Chen, Shi; van de Vrugt, Henri J; Critser, John; Arwert, Fre; Haneline, Laura S; Clapp, D Wade

2006-12-15

Fanconi anemia (FA) is a heterogeneous genetic disorder characterized by bone marrow (BM) failure and cancer susceptibility. Identification of the cDNAs of FA complementation types allows the potential of using gene transfer technology to introduce functional cDNAs as transgenes into autologous stem cells and provide a cure for the BM failure in FA patients. However, strategies to enhance the mobilization, transduction, and engraftment of exogenous stem cells are required to optimize efficacy prior to widespread clinical use. Hypersensitivity of Fancc-/- cells to interferon-gamma (IFN-gamma), a nongenotoxic immune-regulatory cytokine, enhances engraftment of syngeneic wild-type (WT) cells in Fancc-/- mice. However, whether this phenotype is of broad relevance in other FA complementation groups is unresolved. Here we show that primitive and mature myeloid progenitors in Fanca-/- and Fancg-/- mice are hypersensitive to IFN-gamma and that in vivo infusion of IFN-gamma at clinically relevant concentrations was sufficient to allow consistent long-term engraftment of isogenic WT repopulating stem cells. Given that FANCA, FANCC, and FANCG complementation groups account for more than 90% of all FA patients, these data provide evidence that IFN-gamma conditioning may be a useful nongenotoxic strategy for myelopreparation in FA patients.

Understanding Xeroderma Pigmentosum Complementation Groups Using Gene Expression Profiling after UV-Light Exposure.

PubMed

Bowden, Nikola A; Beveridge, Natalie J; Ashton, Katie A; Baines, Katherine J; Scott, Rodney J

2015-07-14

Children with the recessive genetic disorder Xeroderma Pigmentosum (XP) have extreme sensitivity to UV-light, a 10,000-fold increase in skin cancers from age 2 and rarely live beyond 30 years. There are seven genetic subgroups of XP, which are all resultant of pathogenic mutations in genes in the nucleotide excision repair (NER) pathway and a XP variant resultant of a mutation in translesion synthesis, POLH. The clinical symptoms and severity of the disease is varied across the subgroups, which does not correlate with the functional position of the affected protein in the NER pathway. The aim of this study was to further understand the biology of XP subgroups, particularly those that manifest with neurological symptoms. Whole genome gene expression profiling of fibroblasts from each XP complementation group was assessed before and after UV-light exposure. The biological pathways with altered gene expression after UV-light exposure were distinct for each subtype and contained oncogenic related functions such as perturbation of cell cycle, apoptosis, proliferation and differentiation. Patients from the subgroups XP-B and XP-F were the only subgroups to have transcripts associated with neuronal activity altered after UV-light exposure. This study will assist in furthering our understanding of the different subtypes of XP which will lead to better diagnosis, treatment and management of the disease.

Understanding Xeroderma Pigmentosum Complementation Groups Using Gene Expression Profiling after UV-Light Exposure

PubMed Central

Bowden, Nikola A.; Beveridge, Natalie J.; Ashton, Katie A.; Baines, Katherine J.; Scott, Rodney J.

2015-01-01

Children with the recessive genetic disorder Xeroderma Pigmentosum (XP) have extreme sensitivity to UV-light, a 10,000-fold increase in skin cancers from age 2 and rarely live beyond 30 years. There are seven genetic subgroups of XP, which are all resultant of pathogenic mutations in genes in the nucleotide excision repair (NER) pathway and a XP variant resultant of a mutation in translesion synthesis, POLH. The clinical symptoms and severity of the disease is varied across the subgroups, which does not correlate with the functional position of the affected protein in the NER pathway. The aim of this study was to further understand the biology of XP subgroups, particularly those that manifest with neurological symptoms. Whole genome gene expression profiling of fibroblasts from each XP complementation group was assessed before and after UV-light exposure. The biological pathways with altered gene expression after UV-light exposure were distinct for each subtype and contained oncogenic related functions such as perturbation of cell cycle, apoptosis, proliferation and differentiation. Patients from the subgroups XP-B and XP-F were the only subgroups to have transcripts associated with neuronal activity altered after UV-light exposure. This study will assist in furthering our understanding of the different subtypes of XP which will lead to better diagnosis, treatment and management of the disease. PMID:26184184

[Molecular basis of Fanconi's anemia].

PubMed

Digweed, M

1999-01-01

Fanconi anaemia (FA) is an autosomal recessive genetic disorder characterised clinically by progressive bone marrow failure, skeletal deformities and a predisposition to neoplasia. Patient cells manifest an extreme chromosomal instability and hypersensitivity to polyfunctional alkylating agents. It is assumed that the basic defect is related to the repair of DNA damage, in particular that of so-called DNA crosslinks. Currently there are eight complementation groups in FA (FA-A-FA-H) which indicates that at least eight independent genes can lead to FA. Three of these genes have been identified: FANCA, FANCC and FANCG. In this review, the molecular biology and genetics of FA are presented and possible functions of the FANC proteins are discussed.

Genetic fidelity and variability of micropropagated cassava plants (Manihot esculenta Crantz) evaluated using ISSR markers.

PubMed

Vidal, Á M; Vieira, L J; Ferreira, C F; Souza, F V D; Souza, A S; Ledo, C A S

2015-07-14

Molecular markers are efficient for assessing the genetic fidelity of various species of plants after in vitro culture. In this study, we evaluated the genetic fidelity and variability of micropropagated cassava plants (Manihot esculenta Crantz) using inter-simple sequence repeat markers. Twenty-two cassava accessions from the Embrapa Cassava & Fruits Germplasm Bank were used. For each accession, DNA was extracted from a plant maintained in the field and from 3 plants grown in vitro. For DNA amplification, 27 inter-simple sequence repeat primers were used, of which 24 generated 175 bands; 100 of those bands were polymorphic and were used to study genetic variability among accessions of cassava plants maintained in the field. Based on the genetic distance matrix calculated using the arithmetic complement of the Jaccard's index, genotypes were clustered using the unweighted pair group method using arithmetic averages. The number of bands per primer was 2-13, with an average of 7.3. For most micropropagated accessions, the fidelity study showed no genetic variation between plants of the same accessions maintained in the field and those maintained in vitro, confirming the high genetic fidelity of the micropropagated plants. However, genetic variability was observed among different accessions grown in the field, and clustering based on the dissimilarity matrix revealed 7 groups. Inter-simple sequence repeat markers were efficient for detecting the genetic homogeneity of cassava plants derived from meristem culture, demonstrating the reliability of this propagation system.

Gene Copy-Number Variations (CNVs) of Complement C4 and C4A Deficiency in Genetic Risk and Pathogenesis of Juvenile Dermatomyositis

PubMed Central

Lintner, Katherine E.; Patwardhan, Anjali; Rider, Lisa G.; Abdul-Aziz, Rabheh; Wu, Yee Ling; Lundström, Emeli; Padyukov, Leonid; Zhou, Bi; Alhomosh, Alaaedin; Newsom, David; White, Peter; Jones, Karla B.; O’Hanlon, Terrance P.; Miller, Frederick W.; Spencer, Charles H.; Yu, C. Yung

2017-01-01

Objective Complement-mediated vasculopathy of muscle and skin are clinical features of juvenile dermatomyositis (JDM). We assess gene copy-number variations (CNVs) for complement C4 and its isotypes, C4A and C4B, in genetic risks and pathogenesis of JDM. Methods The study population included 105 JDM patients and 500 healthy European Americans. Gene copy-numbers (GCNs) for total C4, C4A, C4B and HLA-DRB1 genotypes were determined by Southern blots and PCRs. Processed activation product C4d bound to erythrocytes (E-C4d) was measured by flow cytometry. Global gene-expression microarrays were performed in 19 JDM and 7 controls using PAXgene-blood RNA. Differential expression levels for selected genes were validated by qPCR. Results Significantly lower GCNs and differences in distribution of GCN groups for total C4 and C4A were observed between JDM and controls. Lower GCN of C4A in JDM remained among HLA DR3-positive subjects (p=0.015). Homozygous or heterozygous C4A-deficiency was present in 40.0% of JDM compared to 18.2% of controls [odds ratio (OR)=3.00 (1.87–4.79), p=8.2x10−6]. JDM had higher levels of E-C4d than controls (p=0.004). In JDM, C4A-deficient subjects had higher levels of E-C4d (p=0.0003) and higher frequency of elevated levels of multiple serum muscle enzymes at diagnosis (p=0.004). Microarray profiling of blood RNA revealed upregulation of type I Interferon-stimulated genes and lower abundance of transcripts for T-cell and chemokine function genes in JDM, but this was less prominent among C4A-deficient or DR3-positive patients. Conclusions Complement C4A-deficiency appears to be an important factor for the genetic risk and pathogenesis of JDM, particularly in patients with a DR3-positive background. PMID:26493816

The role of molecular genetics in diagnosing familial hematuria(s).

PubMed

Deltas, Constantinos; Pierides, Alkis; Voskarides, Konstantinos

2012-08-01

Familial microscopic hematuria (MH) of glomerular origin represents a heterogeneous group of monogenic conditions involving several genes, some of which remain unknown. Recent advances have increased our understanding and our ability to use molecular genetics for diagnosing such patients, enabling us to study their clinical characteristics over time. Three collagen IV genes, COL4A3, COL4A4, and COL4A5 explain the autosomal and X-linked forms of Alport syndrome (AS), and a subset of thin basement membrane nephropathy (TBMN). A number of X-linked AS patients follow a milder course reminiscent of that of patients with heterozygous COL4A3/COL4A4 mutations and TBMN, while at the same time a significant subset of patients with TBMN and familial MH progress to chronic kidney disease (CKD) or end-stage kidney disease (ESKD). A mutation in CFHR5, a member of the complement factor H family of genes that regulate complement activation, was recently shown to cause isolated C3 glomerulopathy, presenting with MH in childhood and demonstrating a significant risk for CKD/ESKD after 40 years old. Through these results molecular genetics emerges as a powerful tool for a definite diagnosis when all the above conditions enter the differential diagnosis, while in many at-risk related family members, a molecular diagnosis may obviate the need for another renal biopsy.

Flicker-induced retinal vasodilatation is not dependent on complement factor H polymorphism in healthy young subjects.

PubMed

Told, Reinhard; Palkovits, Stefan; Boltz, Agnes; Schmidl, Doreen; Napora, Katarzyna J; Werkmeister, René M; Haslacher, Helmuth; Frantal, Sophie; Popa-Cherecheanu, Alina; Schmetterer, Leopold; Garhöfer, Gerhard

2014-11-01

The complement factor H (CFH) tyrosine 402 histidine (Y402H, rs1061170) variant is known to be significantly associated with age-related macular degeneration (AMD). Whether this genetic variant may impact retinal blood flow regulation is largely unknown. This study investigated whether flicker-induced vasodilation, an indicator for the coupling between neural activity and blood flow, is altered in subjects carrying the rs1061170 risk allele. One hundred healthy subjects (aged between 18 and 45 years) were included in this study. Retinal blood flow regulation was tested by assessing retinal vessel calibres in response to stimulation with diffuse flicker light. Retinal vascular flicker responses were determined with a Dynamic Vessel Analyzer (DVA). In addition, genotyping for rs1061170 was performed. Eighteen subjects were homozygous for the risk allele C, 50 were homozygous for the ancestral allele T, and 31 subjects were heterozygous (CT). One subject had to be excluded from data evaluation, as no genetic analysis could be performed due to technical difficulties. Baseline diameters of retinal arteries (p = 0.39) and veins (p = 0.64) were comparable between the three groups. Flicker-induced vasodilation in both retinal arteries (p = 0.38) and retinal veins (p = 0.62) was also comparable between the three studied groups. Our data indicate that homozygous healthy young carriers of the C risk allele at rs1061170 do not show abnormal flicker-induced vasodilation in the retina. This suggests that the high-risk genetic variant of CFH polymorphism does not impact neuro-vascular coupling in healthy subjects. © 2014 The Authors. Acta Ophthalmologica published by John Wiley & Sons Ltd on behalf of Acta Ophthalmologica Scandinavica Foundation.

The identification of novel loci required for appropriate nodule development in Medicago truncatula.

PubMed

Domonkos, Agota; Horvath, Beatrix; Marsh, John F; Halasz, Gabor; Ayaydin, Ferhan; Oldroyd, Giles E D; Kalo, Peter

2013-10-11

The formation of functional symbiotic nodules is the result of a coordinated developmental program between legumes and rhizobial bacteria. Genetic analyses in legumes have been used to dissect the signaling processes required for establishing the legume-rhizobial endosymbiotic association. Compared to the early events of the symbiotic interaction, less attention has been paid to plant loci required for rhizobial colonization and the functioning of the nodule. Here we describe the identification and characterization of a number of new genetic loci in Medicago truncatula that are required for the development of effective nitrogen fixing nodules. Approximately 38,000 EMS and fast neutron mutagenized Medicago truncatula seedlings were screened for defects in symbiotic nitrogen fixation. Mutant plants impaired in nodule development and efficient nitrogen fixation were selected for further genetic and phenotypic analysis. Nine mutants completely lacking in nodule formation (Nod-) represented six complementation groups of which two novel loci have been identified. Eight mutants with ineffective nodules (Fix-) represented seven complementation groups, out of which five were new monogenic loci. The Fix- M. truncatula mutants showed symptoms of nitrogen deficiency and developed small white nodules. Microscopic analysis of Fix- nodules revealed that the mutants have defects in the release of rhizobia from infection threads, differentiation of rhizobia and maintenance of persistence of bacteria in nodule cells. Additionally, we monitored the transcriptional activity of symbiosis specific genes to define what transcriptional stage of the symbiotic process is blocked in each of the Fix- mutants. Based on the phenotypic and gene expression analysis a functional hierarchy of the FIX genes is proposed. The new symbiotic loci of M. truncatula isolated in this study provide the foundation for further characterization of the mechanisms underpinning nodulation, in particular the later stages associated with bacterial release and nodule function.

An example of demographic anthropology, the study of matrimonial exchanges--endogamy, choice of spouse and preferential marriage.

PubMed

Cazes, Marie-Hélène

2006-09-01

The development of demographic studies in anthropology is directly linked to the success of population genetics. The anthropodemographic or anthropogenetic approach is thus underpinned by questions of genetics. While demographers focus on population dynamics and renewal in quantitative terms, population geneticists refer not to individuals but to the sets of genes carried by individuals in a population. Their aim is to detect the factors and processes which influence the genetic evolution of a group, i.e. which modify gene frequencies from one generation to the next. Among them are the factors which affect modes of reproduction. To illustrate the association of these three approaches, i.e. demographic, anthropological and genetic, I use here the example of matrimonial exchanges--which lie at the heart of the population renewal process--among the Dogon of Boni, a Malian ethnic group living in the southern Sahel. We can see how successive analyses--starting with endogamy at macroscopic level and moving down to the individual with choice of spouse and preferential marriage-- combining both quantitative and qualitative approaches, can be used to obtain a detailed description of matrimonial exchanges which shed light upon and complement the three different viewpoints.

Smoking and long-term labour market outcomes.

PubMed

Böckerman, Petri; Hyytinen, Ari; Kaprio, Jaakko

2015-07-01

To examine the long-term effects of smoking on labour market outcomes using twin data matched to register-based individual information on earnings. Twin data for Finnish men born 1945-1957 was used to remove the shared environmental and genetic factors. The results were subjected to extensive robustness testing. Lifetime cigarette consumption was measured by (cumulative) cigarette pack-years in early adulthood. The average of an individual's earnings (and, alternatively, taxable income) was measured over a subsequent 15-year period in later adulthood. Smokers have lower long-term income and earnings. For example, controlling for the shared environmental and genetic factors using the data on genetically identical twins, smoking is negatively associated with lifetime income (p=0.015). The negative association was also robust to the use of various covariates, such as education, health indicators and extraversion. Smoking is negatively related to long-term labour market outcomes. The provision of information about the indirect monetary costs of smoking may thus complement the policy efforts that aim at educating consumers about the health costs of smoking. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

From Drosophila to humans: Reflections on the roles of the prolyl-isomerases and chaperones, cyclophilins, in cell function and disease

PubMed Central

Ferreira, Paulo A.; Orry, Andrew

2013-01-01

Despite remarkable advances in human genetics and other genetic model systems, the fruit fly, Drosophila melanogaster, remains a powerful experimental tool to probe with ease the inner workings of a myriad of biological and pathological processes, even when evolutionary forces impart apparent divergences to some of such processes. The understanding of such evolutionary differences provides mechanistic insights into genotype-phenotype correlations underpinning biological processes across metazoans. The pioneering work developed by the William Pak laboratory for the past four decades, and the work of others, epitomize the notion of how the Drosophila system breaks new fertile ground or complements research fields of high scientific and medical relevance. Among the three major genetic complementation groups produced by the Pak's laboratory and impairing distinct facets of photoreceptor neuronal function, the nina group (ninaA….J) selectively affects the biogenesis of G protein-coupled receptors (GPCR) mediating the photoconversion and transduction of light-stimuli. Among the nina genes identified, ninaA arguably assumes heightened significance for several reasons. First, it presents unique physiological selectivity toward the biogenesis of a subset of GPCRs, a standalone biological manifestation yet to be discerned for most mammalian homologues of NinaA. Second, NinaA belongs to a family of proteins, immunophilins, which are the primary targets for immunosuppressive drugs at the therapeutic forefront of a multitude of medical conditions. Third, NinaA closest homologue, cyclophilin-B (CyPB/PPIB), is an immunophilin whose loss-of-function was found recently to cause osteogenesis imperfecta in the human. This report highlights advances made by studies on some members of immunophilins, the cyclophilins. Finally, it re-examines critically data and dogmas derived from past and recent genetic, structural, biological and pathological studies on NinaA and few other cyclophilins that support some of such paradigms to be less than definite and advance our understanding of cyclophilins' roles in cell function, disease and therapeutic interventions. PMID:22332926

Phenylalanine 445 within oxidosqualene-lanosterol cyclase from Saccharomyces cerevisiae influences C-Ring cyclization and deprotonation reactions.

PubMed

Wu, Tung-Kung; Liu, Yuan-Ting; Chiu, Feng-Hsuan; Chang, Cheng-Hsiang

2006-10-12

[reaction: see text] We describe the Saccharomyces cerevisiae oxidosqualene-lanosterol cyclase Phe445 site-saturated mutants that generate truncated tricyclic and altered deprotonation product profiles. Among these mutants, only polar side-chain group substitutions genetically complemented yeast viability and produced spatially related product diversity, supporting the Johnson model that cation-pi interactions between a carbocationic intermediate and an enzyme can be replaced by an electrostatic or polar side chain to stabilize the cationic intermediate, but with product differentiation.

The population genetics of Quechuas, the largest native South American group: autosomal sequences, SNPs, and microsatellites evidence high level of diversity.

PubMed

Scliar, Marilia O; Soares-Souza, Giordano B; Chevitarese, Juliana; Lemos, Livia; Magalhães, Wagner C S; Fagundes, Nelson J; Bonatto, Sandro L; Yeager, Meredith; Chanock, Stephen J; Tarazona-Santos, Eduardo

2012-03-01

Elucidating the pattern of genetic diversity for non-European populations is necessary to make the benefits of human genetics research available to individuals from these groups. In the era of large human genomic initiatives, Native American populations have been neglected, in particular, the Quechua, the largest South Amerindian group settled along the Andes. We characterized the genetic diversity of a Quechua population in a global setting, using autosomal noncoding sequences (nine unlinked loci for a total of 16 kb), 351 unlinked SNPs and 678 microsatellites and tested predictions of the model of the evolution of Native Americans proposed by (Tarazona-Santos et al.: Am J Hum Genet 68 (2001) 1485-1496). European admixture is <5% and African ancestry is barely detectable in the studied population. The largest genetic distances were between African versus Quechua or Melanesian populations, which is concordant with the African origin of modern humans and the fact that South America was the last part of the world to be peopled. The diversity in the Quechua population is comparable with that of Eurasian populations, and the allele frequency spectrum based on resequencing data does not reflect a reduction in the proportion of rare alleles. Thus, the Quechua population is a large reservoir of common and rare genetic variants of South Amerindians. These results are consistent with and complement our evolutionary model of South Amerindians (Tarazona-Santos et al.: Am J Hum Genet 68 (2001) 1485-1496), proposed based on Y-chromosome data, which predicts high genomic diversity due to the high level of gene flow between Andean populations and their long-term effective population size. Copyright © 2012 Wiley Periodicals, Inc.

The mitochondrial COB region in yeast codes for apocytochrome b and is mosaic.

PubMed

Haid, A; Schweyen, R J; Bechmann, H; Kaudewitz, F; Solioz, M; Schatz, G

1979-03-01

Mitochondrial mutants of Saccharomyces cerevisiae defective in cytochrome b were analyzed genetically and biochemically in order to elucidate the role of the mitochondrial genetic system in the biosynthesis of this cytochrome. The mutants mapped between OLI1 and OLI2 on mitochondrial DNA in a region called COB. A fine structure map of the COB region was constructed by rho- deletion mapping and recombination analysis. The combined genetic and biochemical data indicate that the COB region is mosaic and contains at least five distinct clusters of mutants, A-E, with A being closest to OLI2 and E being closest to OLI1. Clusters A, C and E are probably coding regions for apocytochrome b, whereas clusters B and D seem to be involved in as yet unknown functions. These conclusions rest on the following evidence. 1. Most mutants in clusters A, C and E have specifically lost cytochrome b. Many of them accumulate smaller mitochondrial translation products; some of these were identified as fragments of apocytochrome b by proteolytic fingerprinting. The molecular weight of these fragments depends on the map position of the mutant, increasing in the direction OLI2 leads to OLI1. The mutant closest to OLI1 accumulates an apocytochrome b which is slightly larger than that of wild type. 2. A mutant in cluster C exhibits a spectral absorption band of cytochrome b that is shifted 1.5 nm to the red. 3. Mutants in clusters B and D are pleiotropic. A majority of them are conditional and lack the absorption bands of both cytochrome b and cytochrome aa3; these mutants also fail to accumulate apocytochrome b and subunit I of cytochrome c oxidase and instead form a large number of abnormal translation products whose nature is unknown. 4. Zygotic complementation tests reveal at least two complementation groups: The first group includes all mutants in cluster B and the second group includes mutants in clusters (A + C + D + E).

Complement Activation in Inflammatory Skin Diseases

PubMed Central

Giang, Jenny; Seelen, Marc A. J.; van Doorn, Martijn B. A.; Rissmann, Robert; Prens, Errol P.; Damman, Jeffrey

2018-01-01

The complement system is a fundamental part of the innate immune system, playing a crucial role in host defense against various pathogens, such as bacteria, viruses, and fungi. Activation of complement results in production of several molecules mediating chemotaxis, opsonization, and mast cell degranulation, which can contribute to the elimination of pathogenic organisms and inflammation. Furthermore, the complement system also has regulating properties in inflammatory and immune responses. Complement activity in diseases is rather complex and may involve both aberrant expression of complement and genetic deficiencies of complement components or regulators. The skin represents an active immune organ with complex interactions between cellular components and various mediators. Complement involvement has been associated with several skin diseases, such as psoriasis, lupus erythematosus, cutaneous vasculitis, urticaria, and bullous dermatoses. Several triggers including auto-antibodies and micro-organisms can activate complement, while on the other hand complement deficiencies can contribute to impaired immune complex clearance, leading to disease. This review provides an overview of the role of complement in inflammatory skin diseases and discusses complement factors as potential new targets for therapeutic intervention. PMID:29713318

Women as Mendelians and Geneticists

NASA Astrophysics Data System (ADS)

Richmond, Marsha L.

2015-01-01

After the rediscovery of Mendel's laws of heredity in 1900, the biologists who began studying heredity, variation, and evolution using the new Mendelian methodology—performing controlled hybrid crosses and statistically analyzing progeny to note the factorial basis of characters—made great progress. By 1910, the validity of Mendelism was widely recognized and the field William Bateson christened `genetics' was complemented by the chromosome theory of heredity of T. H. Morgan and his group in the United States. Historians, however, have largely overlooked an important factor in the early establishment of Mendelism and genetics: the large number of women who contributed to the various research groups. This article examines the social, economic, and disciplinary context behind this new wave of women's participation in science and describes the work of women Mendelians and geneticists employed at three leading experimental research institutes, 1900-1940. It argues that the key to more women working in science was the access to higher education and the receptivity of emerging interdisciplinary fields such as genetics to utilize the expertise of women workers, which not only advanced the discipline but also provided new opportunities for women's employment in science.

Genetics Home Reference: complement factor I deficiency

MedlinePlus

... F, Zelazko M, Marquart H, Muller K, Sjöholm AG, Truedsson L, Villoutreix BO, Blom AM. Genetic, molecular ... qualified healthcare professional . About Selection Criteria for Links Data Files & API Site Map Subscribe Customer Support USA. ...

Development of effective skin cancer treatment and prevention in xeroderma pigmentosum.

PubMed

Lambert, W Clark; Lambert, Muriel W

2015-01-01

Xeroderma pigmentosum (XP) is a rare, recessively transmitted genetic disease characterized by increasingly marked dyspigmentation and xerosis (dryness) of sun-exposed tissues, especially skin. Skin cancers characteristically develop in sun-exposed sites at very much earlier ages than in the general population; these are often multiple and hundreds or even thousands may develop. Eight complementation groups have been identified. Seven groups, XP-A…G, are associated with defective genes encoding proteins involved in the nucleotide excision DNA repair (NER) pathway that recognizes and excises mutagenic changes induced in DNA by sunlight; the eighth group, XP-V, is associated with defective translesion synthesis (TLS) bypassing such alterations. The dyspigmentation, xerosis and eventually carcinogenesis in XP patients appear to be due to their cells' failure to respond properly to these mutagenic DNA alterations, leading to mutations in skin cells. A subset of cases, especially those in some complementation groups, may develop neurological degeneration, which may be severe. However, in most XP patients, in the past the multiple skin cancers have led to death at an early age due to either metastases or sepsis. Using either topical 5-fluorouracil or imiquimod, we have developed a protocol that effectively prevents most skin cancer development in XP patients. © 2014 The American Society of Photobiology.

Isolation and Characterization of Mms-Sensitive Mutants of SACCHAROMYCES CEREVISIAE

PubMed Central

Prakash, Louise; Prakash, Satya

1977-01-01

We have isolated mutants sensitive to methyl methanesulfonate (MMS) in Saccharomyces cerevisiae. Alleles of rad1, rad4, rad6, rad52, rad55 and rad57 were found among these mms mutants. Twenty-nine of the mms mutants which complement the existing radiation-sensitive (rad and rev ) mutants belong to 22 new complementation groups. Mutants from five complementation groups are sensitive only to MMS. Mutants of 11 complementation groups are sensitive to UV or X rays in addition to MMS, mutants of six complementation groups are sensitive to all three agents. The cross-sensitivities of these mms mutants to UV and X rays are discussed in terms of their possible involvement in DNA repair. Sporulation is reduced or absent in homozygous diploids of mms mutants from nine complementation groups. PMID:195865

Phenotypic complementation of genetic immunodeficiency by chronic herpesvirus infection

PubMed Central

MacDuff, Donna A; Reese, Tiffany A; Kimmey, Jacqueline M; Weiss, Leslie A; Song, Christina; Zhang, Xin; Kambal, Amal; Duan, Erning; Carrero, Javier A; Boisson, Bertrand; Laplantine, Emmanuel; Israel, Alain; Picard, Capucine; Colonna, Marco; Edelson, Brian T; Sibley, L David; Stallings, Christina L; Casanova, Jean-Laurent; Iwai, Kazuhiro; Virgin, Herbert W

2015-01-01

Variation in the presentation of hereditary immunodeficiencies may be explained by genetic or environmental factors. Patients with mutations in HOIL1 (RBCK1) present with amylopectinosis-associated myopathy with or without hyper-inflammation and immunodeficiency. We report that barrier-raised HOIL-1-deficient mice exhibit amylopectin-like deposits in the myocardium but show minimal signs of hyper-inflammation. However, they show immunodeficiency upon acute infection with Listeria monocytogenes, Toxoplasma gondii or Citrobacter rodentium. Increased susceptibility to Listeria was due to HOIL-1 function in hematopoietic cells and macrophages in production of protective cytokines. In contrast, HOIL-1-deficient mice showed enhanced control of chronic Mycobacterium tuberculosis or murine γ-herpesvirus 68 (MHV68), and these infections conferred a hyper-inflammatory phenotype. Surprisingly, chronic infection with MHV68 complemented the immunodeficiency of HOIL-1, IL-6, Caspase-1 and Caspase-1;Caspase-11-deficient mice following Listeria infection. Thus chronic herpesvirus infection generates signs of auto-inflammation and complements genetic immunodeficiency in mutant mice, highlighting the importance of accounting for the virome in genotype-phenotype studies. DOI: http://dx.doi.org/10.7554/eLife.04494.001 PMID:25599590

Phenotypic complementation of genetic immunodeficiency by chronic herpesvirus infection.

PubMed

MacDuff, Donna A; Reese, Tiffany A; Kimmey, Jacqueline M; Weiss, Leslie A; Song, Christina; Zhang, Xin; Kambal, Amal; Duan, Erning; Carrero, Javier A; Boisson, Bertrand; Laplantine, Emmanuel; Israel, Alain; Picard, Capucine; Colonna, Marco; Edelson, Brian T; Sibley, L David; Stallings, Christina L; Casanova, Jean-Laurent; Iwai, Kazuhiro; Virgin, Herbert W

2015-01-20

Variation in the presentation of hereditary immunodeficiencies may be explained by genetic or environmental factors. Patients with mutations in HOIL1 (RBCK1) present with amylopectinosis-associated myopathy with or without hyper-inflammation and immunodeficiency. We report that barrier-raised HOIL-1-deficient mice exhibit amylopectin-like deposits in the myocardium but show minimal signs of hyper-inflammation. However, they show immunodeficiency upon acute infection with Listeria monocytogenes, Toxoplasma gondii or Citrobacter rodentium. Increased susceptibility to Listeria was due to HOIL-1 function in hematopoietic cells and macrophages in production of protective cytokines. In contrast, HOIL-1-deficient mice showed enhanced control of chronic Mycobacterium tuberculosis or murine γ-herpesvirus 68 (MHV68), and these infections conferred a hyper-inflammatory phenotype. Surprisingly, chronic infection with MHV68 complemented the immunodeficiency of HOIL-1, IL-6, Caspase-1 and Caspase-1;Caspase-11-deficient mice following Listeria infection. Thus chronic herpesvirus infection generates signs of auto-inflammation and complements genetic immunodeficiency in mutant mice, highlighting the importance of accounting for the virome in genotype-phenotype studies.

Complement component C3 plays a critical role in protecting the aging retina in a murine model of age-related macular degeneration.

PubMed

Hoh Kam, Jaimie; Lenassi, Eva; Malik, Talat H; Pickering, Matthew C; Jeffery, Glen

2013-08-01

Complement component C3 is the central complement component and a key inflammatory protein activated in age-related macular degeneration (AMD). AMD is associated with genetic variation in complement proteins that results in enhanced activation of C3 through the complement alternative pathway. These include complement factor H (CFH), a negative regulator of C3 activation. Both C3 inhibition and/or CFH augmentation are potential therapeutic strategies in AMD. Herein, we examined retinal integrity in aged (12 months) mice deficient in both factors H and C3 (CFH(-/-).C3(-/-)), CFH alone (CFH(-/-)), or C3 alone (C3(-/-)), and wild-type mice (C57BL/6). Retinal function was assessed by electroretinography, and retinal morphological features were analyzed at light and electron microscope levels. Retinas were also stained for amyloid β (Aβ) deposition, inflammation, and macrophage accumulation. Contrary to expectation, electroretinograms of CFH(-/-).C3(-/-) mice displayed more severely reduced responses than those of other mice. All mutant strains showed significant photoreceptor loss and thickening of Bruch's membrane compared with wild-type C57BL/6, but these changes were greater in CFH(-/-).C3(-/-) mice. CFH(-/-).C3(-/-) mice had significantly more Aβ on Bruch's membrane, fewer macrophages, and high levels of retinal inflammation than the other groups. Our data show that both uncontrolled C3 activation (CFH(-/-)) and complete absence of C3 (CFH(-/-).C3(-/-) and C3(-/-)) negatively affect aged retinas. These findings suggest that strategies that inhibit C3 in AMD may be deleterious. Copyright © 2013 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

A Novel Quantitative Hemolytic Assay Coupled with Restriction Fragment Length Polymorphisms Analysis Enabled Early Diagnosis of Atypical Hemolytic Uremic Syndrome and Identified Unique Predisposing Mutations in Japan

PubMed Central

Yoshida, Yoko; Miyata, Toshiyuki; Matsumoto, Masanori; Shirotani-Ikejima, Hiroko; Uchida, Yumiko; Ohyama, Yoshifumi; Kokubo, Tetsuro; Fujimura, Yoshihiro

2015-01-01

For thrombotic microangiopathies (TMAs), the diagnosis of atypical hemolytic uremic syndrome (aHUS) is made by ruling out Shiga toxin-producing Escherichia coli (STEC)-associated HUS and ADAMTS13 activity-deficient thrombotic thrombocytopenic purpura (TTP), often using the exclusion criteria for secondary TMAs. Nowadays, assays for ADAMTS13 activity and evaluation for STEC infection can be performed within a few hours. However, a confident diagnosis of aHUS often requires comprehensive gene analysis of the alternative complement activation pathway, which usually takes at least several weeks. However, predisposing genetic abnormalities are only identified in approximately 70% of aHUS. To facilitate the diagnosis of complement-mediated aHUS, we describe a quantitative hemolytic assay using sheep red blood cells (RBCs) and human citrated plasma, spiked with or without a novel inhibitory anti-complement factor H (CFH) monoclonal antibody. Among 45 aHUS patients in Japan, 24% (11/45) had moderate-to-severe (≥50%) hemolysis, whereas the remaining 76% (34/45) patients had mild or no hemolysis (<50%). The former group is largely attributed to CFH-related abnormalities, and the latter group has C3-p.I1157T mutations (16/34), which were identified by restriction fragment length polymorphism (RFLP) analysis. Thus, a quantitative hemolytic assay coupled with RFLP analysis enabled the early diagnosis of complement-mediated aHUS in 60% (27/45) of patients in Japan within a week of presentation. We hypothesize that this novel quantitative hemolytic assay would be more useful in a Caucasian population, who may have a higher proportion of CFH mutations than Japanese patients. PMID:25951460

Molecular analysis of genetic diversity among vine accessions using DNA markers.

PubMed

da Costa, A F; Teodoro, P E; Bhering, L L; Tardin, F D; Daher, R F; Campos, W F; Viana, A P; Pereira, M G

2017-04-13

Viticulture presents a number of economic and social advantages, such as increasing employment levels and fixing the labor force in rural areas. With the aim of initiating a program of genetic improvement in grapevine from the State University of the state of Rio de Janeiro North Darcy Ribeiro, genetic diversity between 40 genotypes (varieties, rootstock, and species of different subgenera) was evaluated using Random amplified polymorphic DNA (RAPD) molecular markers. We built a matrix of binary data, whereby the presence of a band was assigned as "1" and the absence of a band was assigned as "0." The genetic distance was calculated between pairs of genotypes based on the arithmetic complement from the Jaccard Index. The results revealed the presence of considerable variability in the collection. Analysis of the genetic dissimilarity matrix revealed that the most dissimilar genotypes were Rupestris du Lot and Vitis rotundifolia because they were the most genetically distant (0.5972). The most similar were genotypes 31 (unidentified) and Rupestris du lot, which showed zero distance, confirming the results of field observations. A duplicate was confirmed, consistent with field observations, and a short distance was found between the variety 'Italy' and its mutation, 'Ruby'. The grouping methods used were somewhat concordant.

Genetic evidence for involvement of classical complement pathway in induction of experimental autoimmune myasthenia gravis.

PubMed

Tüzün, Erdem; Scott, Benjamin G; Goluszko, Elzbieta; Higgs, Stephen; Christadoss, Premkumar

2003-10-01

Abs to acetylcholine receptor (AChR) and complement are the major constituents of pathogenic events causing neuromuscular junction destruction in both myasthenia gravis (MG) and experimental autoimmune MG (EAMG). To analyze the differential roles of the classical vs alternative complement pathways in EAMG induction, we immunized C3(-/-), C4(-/-), C3(+/-), and C4(+/-) mice and their control littermates (C3(+/+) and C4(+/+) mice) with AChR in CFA. C3(-/-) and C4(-/-) mice were resistant to disease, whereas mice heterozygous for C3 or C4 displayed intermediate susceptibility. Although C3(-/-) and C4(-/-) mice had anti-AChR Abs in their sera, anti-AChR IgG production by C3(-/-) mice was significantly suppressed. Both C3(-/-) and C4(-/-) mice had reduced levels of B cells and increased expression of apoptotis inducers (Fas ligand, CD69) and apoptotic cells in lymph nodes. Immunofluorescence studies showed that the neuromuscular junction of C3(-/-) and C4(-/-) mice lacked C3 or membrane attack complex deposits, despite having IgG deposits, thus providing in vivo evidence for the incapacity of anti-AChR IgGs to induce full-blown EAMG without the aid of complements. The data provide the first direct genetic evidence for the classical complement pathway in the induction of EAMG induced by AChR immunization. Accordingly, severe MG and other Ab- and complement-mediated diseases could be effectively treated by inhibiting C4, thus leaving the alternative complement pathway intact.

Genetic organization of the unc-22 IV gene and the adjacent region in Caenorhabditis elegans.

PubMed

Rogalski, T M; Baillie, D L

1985-01-01

The genetic organization of the region immediately adjacent to the unc-22 IV gene in Caenorhabditis elegans has been studied. We have identified twenty essential genes in this interval of approximately 1.5-map units on Linkage Group IV. The mutations that define these genes were positioned by recombination mapping and complementation with several deficiencies. With few exceptions, the positions obtained by these two methods agreed. Eight of the twenty essential genes identified are represented by more than one allele. Three possible internal deletions of the unc-22 gene have been located by intra-genic mapping. In addition, the right end point of a deficiency or an inversion affecting the adjacent genes let-56 and unc-22 has been positioned inside the unc-22 gene.

Cluster Analysis Identifies Distinct Pathogenetic Patterns in C3 Glomerulopathies/Immune Complex-Mediated Membranoproliferative GN.

PubMed

Iatropoulos, Paraskevas; Daina, Erica; Curreri, Manuela; Piras, Rossella; Valoti, Elisabetta; Mele, Caterina; Bresin, Elena; Gamba, Sara; Alberti, Marta; Breno, Matteo; Perna, Annalisa; Bettoni, Serena; Sabadini, Ettore; Murer, Luisa; Vivarelli, Marina; Noris, Marina; Remuzzi, Giuseppe

2018-01-01

Membranoproliferative GN (MPGN) was recently reclassified as alternative pathway complement-mediated C3 glomerulopathy (C3G) and immune complex-mediated membranoproliferative GN (IC-MPGN). However, genetic and acquired alternative pathway abnormalities are also observed in IC-MPGN. Here, we explored the presence of distinct disease entities characterized by specific pathophysiologic mechanisms. We performed unsupervised hierarchical clustering, a data-driven statistical approach, on histologic, genetic, and clinical data and data regarding serum/plasma complement parameters from 173 patients with C3G/IC-MPGN. This approach divided patients into four clusters, indicating the existence of four different pathogenetic patterns. Specifically, this analysis separated patients with fluid-phase complement activation (clusters 1-3) who had low serum C3 levels and a high prevalence of genetic and acquired alternative pathway abnormalities from patients with solid-phase complement activation (cluster 4) who had normal or mildly altered serum C3, late disease onset, and poor renal survival. In patients with fluid-phase complement activation, those in clusters 1 and 2 had massive activation of the alternative pathway, including activation of the terminal pathway, and the highest prevalence of subendothelial deposits, but those in cluster 2 had additional activation of the classic pathway and the highest prevalence of nephrotic syndrome at disease onset. Patients in cluster 3 had prevalent activation of C3 convertase and highly electron-dense intramembranous deposits. In addition, we provide a simple algorithm to assign patients with C3G/IC-MPGN to specific clusters. These distinct clusters may facilitate clarification of disease etiology, improve risk assessment for ESRD, and pave the way for personalized treatment. Copyright © 2018 by the American Society of Nephrology.

Mannan-binding lectin (MBL) gene polymorphisms in ulcerative colitis and Crohn's disease.

PubMed

Rector, A; Lemey, P; Laffut, W; Keyaerts, E; Struyf, F; Wollants, E; Vermeire, S; Rutgeerts, P; Van Ranst, M

2001-10-01

The inflammatory bowel diseases (IBD), Crohn's disease (CD), and ulcerative colitis (UC), are complex multifactorial traits involving both environmental and genetic factors. Mannan-binding lectin (MBL) plays an important role in non-specific immunity and complement activation. Point mutations in codons 52, 54 and 57 of exon 1 of the MBL gene are associated with decreased MBL plasma concentrations and increased susceptibility to various infectious diseases. If these MBL mutations could lead to susceptibility to putative IBD-etiological microbial agents, or could temper the complement-mediated mucosal damage in IBD, MBL could function as the link between certain microbial, immunological and genetic factors in IBD. In this study, we investigated the presence of the codon 52, 54 and 57 mutations of the MBL gene in 431 unrelated IBD patients, 112 affected and 141 unaffected first-degree relatives, and 308 healthy control individuals. In the group of sporadic IBD patients (n = 340), the frequency of the investigated MBL variants was significantly lower in UC patients when compared with CD patients (P = 0.01) and with controls (P = 0.02). These results suggest that MBL mutations which decrease the formation of functional MBL could protect against the clinical development of sporadic UC, but not of CD. This could be explained by the differential T-helper response in both diseases.

Clinical and molecular epidemiological study of xeroderma pigmentosum in China: A case series of 19 patients.

PubMed

Zhou, Eray Yihui; Wang, Huijun; Lin, Zhimiao; Xu, Guiwen; Ma, Zhihong; Zhao, Jiahui; Feng, Cheng; Duo, Lina; Yin, Jinghua; Yang, Yong

2017-01-01

Xeroderma pigmentosum (XP) is a rare genetic disorder which is divided into eight complementation groups: XP-A to XP-G and XP-V. Some XP patients demonstrate severe cutaneous and neurological manifestations, management of which requires timely diagnosis and intervention. We performed clinical evaluation and genetic analysis on 19 patients, the largest cohort of XP to date in China. Twenty-three mutations from six groups were identified, 16 of which were novel. All patients developed marked freckle-like pigmentation on sun-exposed sites while patients with XP-A, XP-D, XP-F and XP-G showed acute sunburn reactions. Only XP-A patients displayed progressive neurological degeneration. A relatively larger proportion of XP-A and XP-C were found in Chinese XP patients. One XP case and two carriers were prenatally determined. This study extended the mutation spectrum of XP in China and may aid in the diagnosis and treatment of Chinese XP patients. © 2016 Japanese Dermatological Association.

Prenatal diagnosis of xeroderma pigmentosum group A in Japan.

PubMed

Moriwaki, Shinichi; Yamashita, Yoshiki; Nakamura, Sachiko; Fujita, Daisuke; Kohyama, Jun; Takigawa, Masahiro; Ohmichi, Masahide

2012-06-01

We performed a prenatal diagnosis for 10 fetuses from nine unrelated Japanese xeroderma pigmentosum complementation group A (XP-A) families. All parents had at least one XP-A child (proband) with a homozygous founder mutation (IVS3-1G>C) in the XPA gene. A genetic analysis was performed by a restriction enzyme; AlwNI fragment length polymorphism of polymerase chain reaction (PCR)-amplified DNA, mostly from amniotic fluid (AF) and cultured cells established from AF. However, for the first family, we tried amniocentesis as well as chorionic villus sampling (CVS). Among the 10 cases, we confirmed the results of PCR-based genetic diagnosis by post-ultraviolet survival of amniotic cells in eight cases. Unfortunately, 6 weeks after CVS and 4 days after the amniocentesis in the first case we examined, the fetus died in utero, the reason for which remains unexplained. We prenatally determined two XP-A cases, six XP-A carriers and two wild-type fetuses, which appears to be consistent with Mendel's law. © 2011 Japanese Dermatological Association.

Restoration seed reserves for assisted gene flow within seed orchards

Treesearch

C.S. Echt; B.S. Crane

2017-01-01

Changing climate and declining forest populations imperil the future of certain forest tree species. To complement forest management and genetic conservation plans, we propose a new paradigm for seedling seed orchards: foster genetic mixing among a variety of seed sources to increase genetic diversity and adaptive potential of seed supplies used for forest restoration...

The updated concept of genome and its implications in biotechnological research and molecular diagnostics.

PubMed

Xiao, Li; Saldivar, Juan-Sebastian; Zhou, Cuilan; Chen, Chengli; Zhang, Jia; Sirois, Pierre; Li, Kai

2009-02-01

We propose a short definition of The full complement of genetic materials possessed by an intracellular parasite, a cell, or an organism. Accordingly, the human genome is the entire complement of inherited genetic materials possessed by an individual person, or possessed by a cell in an individual person. For higher species, the genomic makeup includes DNA in the nucleus and in the organelles regardless of the number of chromosomes and the homoplasmic or heteroplasmic status of the mitochondrial or chloroplastic DNA. Practically, GENOME can be referred to at the molecular, cellular, individual, and species levels, which has various implications in biotechnological research and molecular diagnostics.

Complement factor H and susceptibility to major depressive disorder in Han Chinese.

PubMed

Zhang, Chen; Zhang, Deng-Feng; Wu, Zhi-Guo; Peng, Dai-Hui; Chen, Jun; Ni, Jianliang; Tang, Wenxin; Xu, Lin; Yao, Yong-Gang; Fang, Yi-Ru

2016-05-01

Accumulating evidence suggests that altered immunity contributes to the development of major depressive disorder (MDD). To examine whether complement factor H (CFH), a regulator of activation of the alternative pathway of the complement cascade, confers susceptibility to MDD. Expression analyses were tested in 53 unmedicated people with MDD and 55 healthy controls. A two-stage genetic association analysis was performed in 3323 Han Chinese with or without MDD. Potential associations between CFH single nucleotide polymorphisms and age at MDD onset were evaluated. CFH levels were significantly lower in the MDD group at both protein and mRNA levels (P = 0.009 and P = 0.014 respectively). A regulatory variant in the CFH gene, rs1061170, showed statistically significant genotypic and allelic differences between the MDD and control groups (genotypic P = 0.0005, allelic P = 0.0001). Kaplan-Meier survival analysis showed that age at onset of MDD was significantly associated with the C allele of rs1061170 (log rank statistic χ(2) = 6.82, P = 0.009). The C-allele carriers had a younger age at onset of MDD (22.2 years, s.d. = 4.0) than those without the C allele (23.6 years, s.d. = 4.3). CFH is likely to play an important role in the development of MDD. rs1061170 has an important effect on age at onset of MDD in Han Chinese and may therefore be related to early pathogenesis of MDD, although further study is needed. © The Royal College of Psychiatrists 2016.

In silico characterization of a novel pathogenic deletion mutation identified in XPA gene in a Pakistani family with severe xeroderma pigmentosum.

PubMed

Nasir, Muhammad; Ahmad, Nafees; Sieber, Christian M K; Latif, Amir; Malik, Salman Akbar; Hameed, Abdul

2013-09-24

Xeroderma Pigmentosum (XP) is a rare skin disorder characterized by skin hypersensitivity to sunlight and abnormal pigmentation. The aim of this study was to investigate the genetic cause of a severe XP phenotype in a consanguineous Pakistani family and in silico characterization of any identified disease-associated mutation. The XP complementation group was assigned by genotyping of family for known XP loci. Genotyping data mapped the family to complementation group A locus, involving XPA gene. Mutation analysis of the candidate XP gene by DNA sequencing revealed a novel deletion mutation (c.654del A) in exon 5 of XPA gene. The c.654del A, causes frameshift, which pre-maturely terminates protein and result into a truncated product of 222 amino acid (aa) residues instead of 273 (p.Lys218AsnfsX5). In silico tools were applied to study the likelihood of changes in structural motifs and thus interaction of mutated protein with binding partners. In silico analysis of mutant protein sequence, predicted to affect the aa residue which attains coiled coil structure. The coiled coil structure has an important role in key cellular interactions, especially with DNA damage-binding protein 2 (DDB2), which has important role in DDB-mediated nucleotide excision repair (NER) system. Our findings support the fact of genetic and clinical heterogeneity in XP. The study also predicts the critical role of DDB2 binding region of XPA protein in NER pathway and opens an avenue for further research to study the functional role of the mutated protein domain.

Adherence to a Mediterranean diet, genetic susceptibility, and progression to advanced macular degeneration: a prospective cohort study.

PubMed

Merle, Bénédicte M J; Silver, Rachel E; Rosner, Bernard; Seddon, Johanna M

2015-11-01

Adherence to a Mediterranean-type diet is linked to a lower risk of mortality and chronic disease, but the association with the progression of age-related macular degeneration (AMD) and genetic susceptibility is unknown. We examined the association of adherence to the Mediterranean diet and genetic susceptibility with progression to advanced AMD. Among 2525 subjects in the AREDS (Age-Related Eye Disease Study), 1028 eyes progressed to advanced AMD over 13 y. Baseline data for demographic and behavioral covariates were collected by using questionnaires. Dietary data were collected from food-frequency questionnaires. The alternate Mediterranean diet (aMeDi) score (range: 0-9) was constructed from individual intakes of vegetables, fruit, legumes, whole grains, nuts, fish, red and processed meats, alcohol, and the ratio of monounsaturated to saturated fats. Ten genetic loci in 7 genes [complement factor H (CFH), age-related maculopathy susceptibility 2/high-temperature requirement A serine peptidase 1 (ARMS2/HTRA1), complement component 2 (C2), complement factor B (CFB), complement component 3 (C3), collagen type VIII α 1 (COL8A1), and RAD51 paralog B (RAD51B)] were examined. Survival analysis was used to assess individual eyes for associations between incident AMD and aMeDi score, as well as interaction effects between aMeDi score and genetic variation on risk of AMD. A high aMeDi score (score of 6-9) was significantly associated with a reduced risk of progression to advanced AMD after adjustment for demographic, behavioral, ocular, and genetic covariates (HR: 0.74; 95% CI: 0.61, 0.91; P-trend = 0.007). The aMeDi score was significantly associated with a lower risk of incident advanced AMD among subjects carrying the CFH Y402H nonrisk (T) allele (P-trend = 0.0004, P-interaction = 0.04). The aMeDi score was not associated with AMD among subjects who were homozygous for the risk (C) allele. Higher adherence to a Mediterranean diet was associated with reduced risk of progression to advanced AMD, which may be modified by genetic susceptibility. This trial was registered at clinicaltrials.gov as NCT00594672. © 2015 American Society for Nutrition.

Seed colour loci, homoeology and linkage groups of the C genome chromosomes revealed in Brassica rapa–B. oleracea monosomic alien addition lines

PubMed Central

Heneen, Waheeb K.; Geleta, Mulatu; Brismar, Kerstin; Xiong, Zhiyong; Pires, J. Chris; Hasterok, Robert; Stoute, Andrew I.; Scott, Roderick J.; King, Graham J.; Kurup, Smita

2012-01-01

Background and Aims Brassica rapa and B. oleracea are the progenitors of oilseed rape B. napus. The addition of each chromosome of B. oleracea to the chromosome complement of B. rapa results in a series of monosomic alien addition lines (MAALs). Analysis of MAALs determines which B. oleracea chromosomes carry genes controlling specific phenotypic traits, such as seed colour. Yellow-seeded oilseed rape is a desirable breeding goal both for food and livestock feed end-uses that relate to oil, protein and fibre contents. The aims of this study included developing a missing MAAL to complement an available series, for studies on seed colour control, chromosome homoeology and assignment of linkage groups to B. oleracea chromosomes. Methods A new batch of B. rapa–B. oleracea aneuploids was produced to generate the missing MAAL. Seed colour and other plant morphological features relevant to differentiation of MAALs were recorded. For chromosome characterization, Snow's carmine, fluorescence in situ hybridization (FISH) and genomic in situ hybridization (GISH) were used. Key Results The final MAAL was developed. Morphological traits that differentiated the MAALs comprised cotyledon number, leaf morphology, flower colour and seed colour. Seed colour was controlled by major genes on two B. oleracea chromosomes and minor genes on five other chromosomes of this species. Homoeologous pairing was largely between chromosomes with similar centromeric positions. FISH, GISH and a parallel microsatellite marker analysis defined the chromosomes in terms of their linkage groups. Conclusions A complete set of MAALs is now available for genetic, genomic, evolutionary and breeding perspectives. Defining chromosomes that carry specific genes, physical localization of DNA markers and access to established genetic linkage maps contribute to the integration of these approaches, manifested in the confirmed correspondence of linkage groups with specific chromosomes. Applications include marker-assisted selection and breeding for yellow seeds. PMID:22628364

Mutants Resistant to anti-Microtubule Herbicides Map to a Locus on the Uni Linkage Group in Chlamydomonas Reinhardtii

PubMed Central

James, S. W.; Ranum, LPW.; Silflow, C. D.; Lefebvre, P. A.

1988-01-01

We have used genetic analysis to study the mode of action of two anti-microtubule herbicides, amiprophos-methyl (APM) and oryzalin (ORY). Over 200 resistant mutants were selected by growth on APM- or ORY-containing plates. The 21 independently isolated mutants examined in this study are 3- to 8-fold resistant to APM and are strongly cross-resistant to ORY and butamiphos, a close analog of APM. Two Mendelian genes, apm1 and apm2, are defined by linkage and complementation analysis. There are 20 alleles of apm1 and one temperature-sensitive lethal (33°) allele of apm2. Mapping by two-factor crosses places apm1 6.5 cM centromere proximal to uni1 and within 4 cM of pf7 on the uni linkage group, a genetically circular linkage group comprising genes which affect flagellar assembly or function; apm2 maps near the centromere of linkage group VIII. Allele-specific synthetic lethality is observed in crosses between apm2 and alleles of apm1. Also, self crosses of apm2 are zygotic lethal, whereas crosses of nine apm1 alleles inter se result in normal germination and tetrad viability. The mutants are recessive to their wild-type alleles but doubly heterozygous diploids (apm1 +/+ apm2) made with apm2 and any of 15 apm1 alleles display partial intergenic noncomplementation, expressed as intermediate resistance. Diploids homozygous for mutant alleles of apm1 are 4-6-fold resistant to APM and ORY; diploids homozygous for apm2 are ts(-) and 2-fold resistant to the herbicides. Doubly heterozygous diploids complement the ts(-) phenotype of apm2, but they are typically 1.5-2-fold resistant to APM and ORY. From the results described we suggest that the gene products of apm1 and apm2 may interact directly or function in the same structure or process. PMID:8608924

Bioluminescent indicators for Ca2+ based on split Renilla luciferase complementation in living cells.

PubMed

Kaihara, Asami; Umezawa, Yoshio; Furukawa, Tetsushi

2008-01-01

Genetically encoded bioluminescent indicators for intracellular Ca2+ are described here with CaM-M13 interaction-induced complementation of split Renilla luciferase. The Ca2+-induced interaction between CaM and M13 leads to complementation of the N- and C-terminal halves of split Renilla luciferase in living cells. This intramolecular interaction results in the spontaneous and simultaneous emission of bioluminescence split Renilla luciferase. This is how intracellular Ca2+ is illuminated with the intramolecular complementation of split Renilla luciferase. The Ca2+-dependent spontaneous and simultaneous emission of bioluminescence promises to reveal Ca2+ dynamics in living cells, and also in vivo using the present indicators.

Development of resources and tools for mapping genetic sources of phenotypic variation

USDA-ARS?s Scientific Manuscript database

Commercial and experimental genetic resources were established and investigated for a range of reproductive and disease susceptibility phenotypes. The phenotyping efforts were accompanied with RNA and whole genome sequencing and novel assemblies of the swine genome. The efforts were complemented wit...

Induction of Vermillion in Pyralid moths using CRISPR mutagenesis

USDA-ARS?s Scientific Manuscript database

Eye color mutations have been useful markers of genetic activity or alteration in insect genetics. Complementation or disruption of transport or biosynthesis of ommochrome (brown) or pteridine (red) pigments have provided useful targets for transgenic procedures. Tryptophan oxygenase (To) (EC 1.13.1...

Investigation of FANCA mutations in Greek patients.

PubMed

Selenti, Nikoletta; Sofocleous, Christalena; Kattamis, Antonis; Kolialexi, Aggeliki; Kitsiou, Sophia; Fryssira, Elena; Polychronopoulou, Sophia; Kanavakis, Emmanouel; Mavrou, Ariadni

2013-08-01

Fanconi anemia (FA) is a rare genetic disease characterized by considerable heterogeneity. Fifteen subtypes are currently recognised and deletions of the Fanconi anemia complementation group A (FANCA) gene account for more than 65% of FA cases. We report on the results from a cohort of 166 patients referred to the Department of Medical Genetics of Athens University for genetic investigation after the clinical suspicion of FA. For clastogen-induced chromosome damage, cultures were set up with the addition of mitomycin C (MMC) and diepoxybutane (DEB), respectively. Following a positive cytogenetic result, molecular analysis was performed to allow identification of causative mutations in the FANCA gene. A total of 13/166 patients were diagnosed with FA and 8/13 belonged to the FA-A subtype. A novel point mutation was identified in exon 26 of FANCA gene. In our study 62% of FA patients were classified in the FA-A subtype and a point mutation in exon 26 was noted for the first time.

Structural insights into the functions of the FANCM-FAAP24 complex in DNA repair

PubMed Central

Yang, Hui; Zhang, Tianlong; Tao, Ye; Wang, Fang; Tong, Liang; Ding, Jianping

2013-01-01

Fanconi anemia (FA) is a genetically heterogeneous disorder associated with deficiencies in the FA complementation group network. FA complementation group M (FANCM) and FA-associated protein 24 kDa (FAAP24) form a stable complex to anchor the FA core complex to chromatin in repairing DNA interstrand crosslinks. Here, we report the first crystal structure of the C-terminal segment of FANCM in complex with FAAP24. The C-terminal segment of FANCM and FAAP24 both consist of a nuclease domain at the N-terminus and a tandem helix-hairpin-helix (HhH)2 domain at the C-terminus. The FANCM-FAAP24 complex exhibits a similar architecture as that of ApXPF. However, the variations of several key residues and the electrostatic property at the active-site region render a catalytically inactive nuclease domain of FANCM, accounting for the lack of nuclease activity. We also show that the first HhH motif of FAAP24 is a potential binding site for DNA, which plays a critical role in targeting FANCM-FAAP24 to chromatin. These results reveal the mechanistic insights into the functions of FANCM-FAAP24 in DNA repair. PMID:24003026

Molecular and cellular analysis of the DNA repair defect in a patient in Xeroderma pigmentosum complementation group D who has the clinical features of Xeroderma pigmentosum and Cockayne syndrome

DOE Office of Scientific and Technical Information (OSTI.GOV)

Broughton, B.C.; Thompson, A.F.; Harcourt, S.A.

1995-01-01

Xeroderma pigmentosum (XP) and Cockayne syndrome (CS) are quite distinct genetic disorders that are associated with defects in excision repair of UV-induced DNA damage. A few patients have been described previously with the clinical features of both disorders. In this paper we describe an individual in this category who has unusual cellular responses to UV light. We show that his cultured fibroblasts and lymphocytes are extremely sensitive to irradiation with UV-C, despite a level of nucleotide excision repair that is 30%-40% that of normal cells. The deficiency is assigned to the XP-D complementation group, and we have identified two causativemore » mutations in the XPD gene: a gly{yields}arg change at amino acid 675 in the allele inherited from the patient`s mother and a -1 frameshift at amino acid 669 in the allele inherited from his father. These mutations are in the C-terminal 20% of the 760-amino-acid XPD protein, in a region where we have recently identified several mutations in patients with trichothiodystrophy. 44 refs., 5 figs., 2 tabs.« less

Monogenic diseases associated with intestinal inflammation: implications for the understanding of inflammatory bowel disease.

PubMed

Uhlig, Holm H

2013-12-01

Inflammatory bowel disease (IBD), encompassing Crohn's disease and ulcerative colitis, has multifactorial aetiology with complex interactions between genetic and environmental factors. Over 150 genetic loci are associated with IBD. The genetic contribution of the majority of those loci towards explained heritability is low. Recent studies have reported an increasing spectrum of human monogenic diseases that can present with IBD-like intestinal inflammation. A substantial proportion of patients with those genetic defects present with very early onset of intestinal inflammation. The 40 monogenic defects with IBD-like pathology selected in this review can be grouped into defects in intestinal epithelial barrier and stress response, immunodeficiencies affecting granulocyte and phagocyte activity, hyper- and autoinflammatory disorders as well as defects with disturbed T and B lymphocyte selection and activation. In addition, there are defects in immune regulation affecting regulatory T cell activity and interleukin (IL)-10 signalling. Related to the variable penetrance of the IBD-like phenotype, there is a likely role for modifier genes and gene-environment interactions. Treatment options in this heterogeneous group of disorders range from anti-inflammatory and immunosuppressive therapy to blockade of tumour necrosis factor α and IL-1β, surgery, haematopoietic stem cell transplantation or gene therapy. Understanding of prototypic monogenic 'orphan' diseases cannot only provide treatment options for the affected patients but also inform on immunological mechanisms and complement the functional understanding of the pathogenesis of IBD.

Rare genetic variants in Tunisian Jewish patients suffering from age-related macular degeneration.

PubMed

Pras, Eran; Kristal, Dana; Shoshany, Nadav; Volodarsky, Dina; Vulih, Inna; Celniker, Gershon; Isakov, Ofer; Shomron, Noam; Pras, Elon

2015-07-01

To explore the molecular basis of familial, early onset, age-related macular degeneration (AMD) with diverse phenotypes, using whole exome sequencing (WES). We performed WES on four patients (two sibs from two families) manifesting early-onset AMD and searched for disease-causing genetic variants in previously identified macular degeneration related genes. Validation studies of the variants included bioinformatics tools, segregation analysis of mutations within the families and mutation screening in an AMD cohort of patients. The index patients were in their 50s when diagnosed and displayed a wide variety of clinical AMD presentations: from limited drusen in the posterior pole to multiple basal-laminar drusen extending peripherally. Severe visual impairment due to extensive geographic atrophy and/or choroidal-neovascularisation was common by the age of 75 years. Approximately, 400 000 genomic variants for each DNA sample were included in the downstream bioinformatics analysis, which ended in the discovery of two novel variants; in one family a single bp deletion was identified in the Hemicentin (HMCN1) gene (c.4162delC), whereas in the other, a missense variant (p.V412M) in the Complement Factor-I (CFI) gene was found. Screening for these variants in a cohort of patients with AMD identified another family with the CFI variant. This report uses WES to uncover rare genetic variants in AMD. A null-variant in HMCN1 has been identified in one AMD family, and a missense variant in CFI was discovered in two other families. These variants confirm the genetic complexity and significance of rare genetic variants in the pathogenesis of AMD. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Isolation and preliminary characterization of temperature-sensitive mutants of influenza virus.

PubMed

Sugiura, A; Tobita, K; Kilbourne, E D

1972-10-01

Isolation of temperature-sensitive (ts) mutants was attempted from the WSN strain of influenza A virus which was grown and assayed in MDBK cells. After growth of wild-type virus in the presence of 5-fluorouracil, 15 ts mutants were selected for which the ratio of plaquing efficiency at 39.5 C to that at 33 C was 10(-3) or less. In pairwise crosses of ts mutants, recombination and complementation were either very efficient or undetectable. It is suggested, therefore, that the viral genome consists of physically discrete units and recombination occurs as an exchange of these units. All 15 mutants have been assigned with certainty into five recombination groups. Three mutants are suspected to be double mutants. Any two complementing mutants always recombined with each other, and noncomplementing mutants did not recombine. In physiological tests, mutants showed diverse patterns of functional defects at the nonpermissive temperature. However, it was not always possible to correlate these physiological defects with the results of genetic characterization.

Genetic and antigenic relationships of vesicular stomatitis viruses from South America.

PubMed

Pauszek, Steven J; Barrera, Jose Del C; Goldberg, Tony; Allende, Rossana; Rodriguez, Luis L

2011-11-01

Vesicular stomatitis (VS) viruses have been classified into two serotypes: New Jersey (VSNJV) and Indiana (VSIV). Here, we have characterized field isolates causing vesicular stomatitis in Brazil and Argentina over a 35-year span. Cluster analysis based on either serological relatedness, as inferred from virus neutralization and complement fixation assays, or nucleotide sequences of two separate genes (phosphoprotein or glycoprotein) grouped the field isolates into two distinct monophyletic groups within the Indiana serogroup. One group included seven viruses from Brazil and Argentina that were serologically classified as Indiana-2 and Cocal virus (COCV). The other group contained three viruses from Brazil that were serologically classified as Indiana-3 and the prototype of this group, Alagoas virus (VSAV). Interestingly, two vesiculoviruses that were isolated from insects but do not cause disease in animals, one from Brazil (Maraba virus; MARAV) and the other from Colombia (CoAr 171638), grouped into two separate genetic lineages within the Indiana serotype. Our data provide support for the classification of viruses causing clinical VS in livestock in Brazil and Argentina into two distinct groups: Indiana-2 (VSIV-2) and Indiana-3 (VSIV-3). We suggest using nomenclature for these viruses that includes the serotype, year and place of occurrence, and affected host. This nomenclature is consistent with that currently utilized to describe field isolates of VSNJV or VSIV in scientific literature.

l-Alanine Auxotrophy of Lactobacillus johnsonii as Demonstrated by Physiological, Genomic, and Gene Complementation Approaches

PubMed Central

van der Kaaij, Hengameh; Desiere, Frank; Mollet, Beat; Germond, Jacques-Edouard

2004-01-01

Using a chemically defined medium without l-alanine, Lactobacillus johnsonii was demonstrated to be strictly auxotrophic for that amino acid. A comparative genetic analysis showed that all known genes involved in l-alanine biosynthesis are absent from the genome of L. johnsonii. This auxotrophy was complemented by heterologous expression of the Bacillus subtilis l-alanine dehydrogenase. PMID:15006820

Autoantibodies against complement components in systemic lupus erythematosus - role in the pathogenesis and clinical manifestations.

PubMed

Hristova, M H; Stoyanova, V S

2017-12-01

Many complement structures and a number of additional factors, i.e. autoantibodies, receptors, hormones and cytokines, are implicated in the complex pathogenesis of systemic lupus erythematosus. Genetic defects in the complement as well as functional deficiency due to antibodies against its components lead to different pathological conditions, usually clinically presented. Among them hypocomplementemic urticarial vasculitis, different types of glomerulonephritis as dense deposit disease, IgA nephropathy, atypical haemolytic uremic syndrome and lupus nephritis are very common. These antibodies cause conformational changes leading to pathological activation or inhibition of complement with organ damage and/or limited capacity of the immune system to clear immune complexes and apoptotic debris. Finally, we summarize the role of complement antibodies in the pathogenesis of systemic lupus erythematosus and discuss the mechanism of some related clinical conditions such as infections, thyroiditis, thrombosis, acquired von Willebrand disease, etc.

Genotype-phenotype correlations of low frequency variants in the complement system in renal disease and age-related macular degeneration.

PubMed

Geerlings, M J; Volokhina, E B; de Jong, E K; van de Kar, N; Pauper, M; Hoyng, C B; van den Heuvel, L P; den Hollander, A I

2018-06-11

Genetic alterations in the complement system have been linked to a variety of diseases, including atypical hemolytic uremic syndrome (aHUS), C3 glomerulopathy (C3G), and age-related macular degeneration (AMD). We performed sequence analysis of the complement genes CFH, CFI, and C3 in 866 aHUS/C3G and 697 AMD patients. In total we identified 505 low frequency alleles, representing 121 unique variants, of which 51 are novel. CFH contained the largest number of unique low frequency variants (n=64; 53%), followed by C3 (n=32; 26%) and CFI (n=25; 21%). A substantial number of variants were found in both patients groups (n=48; 40%), while 41 (34%) variants were found only in aHUS/C3G and 32 (26%) variants were AMD-specific. Genotype-phenotype correlations between the disease groups identified a higher frequency of protein-altering alleles in SCR20 of Factor H (FH), and in the serine protease domain of Factor I (FI) in aHUS/C3G patients. In AMD a higher frequency of protein-altering alleles was observed in SCR3, SCR5 and SCR7 of FH, the SRCR domain of FI, and in the MG3 domain of C3. In conclusion, we observed a substantial overlap of variants between aHUS/C3G and AMD, however, there is a distinct clustering of variants within specific domains. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Language and theory of mind in autism spectrum disorder: the relationship between complement syntax and false belief task performance.

PubMed

Lind, Sophie E; Bowler, Dermot M

2009-06-01

This study aimed to test the hypothesis that children with autism spectrum disorder (ASD) use their knowledge of complement syntax as a means of "hacking out" solutions to false belief tasks, despite lacking a representational theory of mind (ToM). Participants completed a "memory for complements" task, a measure of receptive vocabulary, and traditional location change and unexpected contents false belief tasks. Consistent with predictions, the correlation between complement syntax score and location change task performance was significantly stronger within the ASD group than within the comparison group. However, contrary to predictions, complement syntax score was not significantly correlated with unexpected contents task performance within either group. Possible explanations for this pattern of results are considered.

A hypervariable STR polymorphism in the CFI gene: southern origin of East Asian-specific group H alleles.

PubMed

Yuasa, Isao; Jin, Feng; Harihara, Shinji; Matsusue, Aya; Fujihara, Junko; Takeshita, Haruo; Akane, Atsushi; Umetsu, Kazuo; Saitou, Naruya; Chattopadhyay, Prasanta K

2013-09-01

Previous studies of four populations revealed that a hypervariable short tandem repeat (iSTR) in intron 7 of the human complement factor I (CFI) gene on chromosome 4q was unique, with 17 possible East Asian-specific group H alleles observed at relatively high frequencies. To develop a deeper anthropological and forensic understanding of iSTR, 1161 additional individuals from 11 Asian populations were investigated. Group H alleles of iSTR and c.1217A allele of a SNP in exon 11 of the CFI gene were associated with each other and were almost entirely confined to East Asian populations. Han Chinese in Changsha, southern China, showed the highest frequency for East Asian-specific group H alleles (0.201) among 15 populations. Group H alleles were observed to decrease gradually from south to north in 11 East Asian populations. This expansion of group H alleles provides evidence that southern China and Southeast Asia are a hotspot of Asian diversity and a genetic reservoir of Asians after they entered East Asia. The expected heterozygosity values of iSTR ranged from 0.927 in Thais to 0.874 in Oroqens, higher than those of an STR in the fibrinogen alpha chain (FGA) gene on chromosome 4q. Thus, iSTR is a useful marker for anthropological and forensic genetics. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

In silico characterization of a novel pathogenic deletion mutation identified in XPA gene in a Pakistani family with severe xeroderma pigmentosum

PubMed Central

2013-01-01

Background Xeroderma Pigmentosum (XP) is a rare skin disorder characterized by skin hypersensitivity to sunlight and abnormal pigmentation. The aim of this study was to investigate the genetic cause of a severe XP phenotype in a consanguineous Pakistani family and in silico characterization of any identified disease-associated mutation. Results The XP complementation group was assigned by genotyping of family for known XP loci. Genotyping data mapped the family to complementation group A locus, involving XPA gene. Mutation analysis of the candidate XP gene by DNA sequencing revealed a novel deletion mutation (c.654del A) in exon 5 of XPA gene. The c.654del A, causes frameshift, which pre-maturely terminates protein and result into a truncated product of 222 amino acid (aa) residues instead of 273 (p.Lys218AsnfsX5). In silico tools were applied to study the likelihood of changes in structural motifs and thus interaction of mutated protein with binding partners. In silico analysis of mutant protein sequence, predicted to affect the aa residue which attains coiled coil structure. The coiled coil structure has an important role in key cellular interactions, especially with DNA damage-binding protein 2 (DDB2), which has important role in DDB-mediated nucleotide excision repair (NER) system. Conclusions Our findings support the fact of genetic and clinical heterogeneity in XP. The study also predicts the critical role of DDB2 binding region of XPA protein in NER pathway and opens an avenue for further research to study the functional role of the mutated protein domain. PMID:24063568

Total RNA Sequencing Analysis of DCIS Progressing to Invasive Breast Cancer

DTIC Science & Technology

2017-09-01

Public Release; Distribution Unlimited The views , opinions and/or findings contained in this report are those of the author(s) and should not be...STATEMENT Approved for Public Release; Distribution Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT: This project is designed to complement a multi ...fact progress to invasive disease (IBC), and complements our multi -institutional, NIH-funded study of genetic and epigenetic alterations of pre

Complementation of a red-light-indifferent cyanobacterial mutant.

PubMed Central

Chiang, G G; Schaefer, M R; Grossman, A R

1992-01-01

Many cyanobacteria alter their phycobilisome composition in response to changes in light wavelength in a process termed complementary chromatic adaptation. Mutant strains FdR1 and FdR2 of the filamentous cyanobacterium Fremyella diplosiphon are characterized by aberrant chromatic adaptation. Instead of adjusting to different wavelengths of light, FdR1 and FdR2 behave as if they are always in green light; they do not respond to red light. We have previously reported complementation of FdR1 by conjugal transfer of a wild-type genomic library. The complementing DNA has now been localized by genetic analysis to a region on the rescued genomic subclone that contains a gene designated rcaC. This region of DNA is also able to complement FdR2. Southern blot analysis of genomic DNA from FdR1 and FdR2 indicates that these strains harbor DNA insertions within the rcaC sequence that may have resulted from the activity of transposable genetic elements. The predicted amino acid sequence of RcaC shares strong identity to response regulators of bacterial two-component regulatory systems. This relationship is discussed in the context of the signal-transduction pathway mediating regulation of genes encoding phycobilisome polypeptides during chromatic adaptation. Images PMID:1409650

Comparing schizophrenia symptoms in the Iban of Sarawak with other populations to elucidate clinical heterogeneity.

PubMed

McLean, Duncan; Barrett, Robert; Loa, Peter; Thara, Rangaswamy; John, Sujit; McGrath, John; Gratten, Jake; Mowry, Bryan

2015-03-01

The symptom profile of schizophrenia can vary between ethnic groups. We explored selected symptom variables previously reported to be characteristic of schizophrenia in the Iban of Sarawak in transethnic populations from Australia, India, and Sarawak, Malaysia. We tested site differences to confirm previous research, and to explore implications of differences across populations for future investigations. We recruited schizophrenia samples in Australia (n = 609), India (n = 310) and Sarawak (n = 205) primarily for the purposes of genetic studies. We analyzed seven identified variables and their relationship to site using logistic regression, including: global delusions, bizarre delusions, thought broadcast/insertion/withdrawal delusions, global hallucinations, auditory hallucinations, disorganized behavior, and prodromal duration. We identified a distinct symptom profile in our Sarawak sample. Specifically, the Iban exhibit: low frequency of thought broadcast/insertion/withdrawal delusions, high frequency of auditory hallucinations and disorganized behavior, with a comparatively short prodrome when compared with Australian and Indian populations. Understanding between-site variation in symptom profile may complement future transethnic genetic studies, and provide important clues as to the nature of differing schizophrenia expression across ethnically distinct groups. A comprehensive approach to subtyping schizophrenia is warranted, utilizing comprehensively ascertained transethnic samples to inform both schizophrenia genetics and nosology. Copyright © 2013 Wiley Publishing Asia Pty Ltd.

Expansion of the genotypic and phenotypic spectrum of xeroderma pigmentosum in Chinese population.

PubMed

Zhang, Jia; Cheng, Ruhong; Yu, Xia; Sun, Zhonghui; Li, Ming; Yao, Zhirong

2017-01-01

Xeroderma pigmentosum (XP) is a rare genodermatosis characterized by exaggerated sunburn reactions, freckle-like pigmentation, and a high possibility of developing cutaneous tumors. XP comprised seven complementation groups (from XP-A to XP-G) and a variant form XP-V. This study was based on five unrelated Chinese families with six patients clinically suspected to be XP. Mutation screening was performed by direct sequencing of the entire coding region of eight XP genes. All of the pathogenic mutations were identified by mutational analysis, including four novel mutations. Our study successfully identified the pathogenic mutations in six XP patients (three XP-A, one XP-G, one XP-V, and a rare XP-D group in Chinese population). We reviewed the reported XP cases with mutations in the Chinese population and concluded that four complementation groups (XP-A, XP-C, XP-G, and XP-V) that occupy the major proportion should be considered as a first step in genetic detection (especially, XPA is the most common group, and unlike in other populations, XP-G is not rare in the Chinese population). Moreover, XP-D and XP-F, two rare subgroups, should also be added for further mutational analysis. Further, we provide some information for Chinese dermatologists that, when an early diagnosis is made, XP-C and XP-V patients can have relatively good prognoses. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Integration of genomic resources to uncover pleiotropic regions associated with age at puberty and reproductive longevity in sows

USDA-ARS?s Scientific Manuscript database

Commercial and experimental genetic resources were used to investigate genetic pleiotropic factors that influence age at puberty, litter-size and reproductive longevity. The phenotypes were complemented by high-density genotyping and whole genome and RNA sequencing. The SNPs from Porcine SNP60 BeadA...

Genetic diversity, virulence, and Meloidogyne incognita interactions of Fusarium oxysporum isolates causing cotton wilt in Georgia

USDA-ARS?s Scientific Manuscript database

Locally severe outbreaks of Fusarium wilt of cotton (Gossypium spp.) in South Georgia raised concerns about the genotypes of the causal pathogen, Fusarium oxysporum f. sp. vasinfectum. Vegetative complementation tests and DNA sequence analysis were used to determine genetic diversity among 492 F. ox...

Cfh genotype interacts with dietary glycemic index to modulate age-related macular degeneration-like features in mice

USDA-ARS?s Scientific Manuscript database

Age-related macular degeneration (AMD) is a leading cause of visual impairment worldwide. Genetics and diet contribute to the relative risk for developing AMD, but their interactions are poorly understood. Genetic variations in Complement Factor H (CFH), and dietary glycemic index (GI) are major ris...

Complement component 4

MedlinePlus

... of a certain protein. This protein is part of the complement system. The complement system is a group of proteins ... system and play a role in the development of inflammation. The complement system protects the body from infections, dead cells and ...

Genetically engineered pigs and target-specific immunomodulation provide significant graft survival and hope for clinical cardiac xenotransplantation.

PubMed

Mohiuddin, Muhammad M; Singh, Avneesh K; Corcoran, Philip C; Hoyt, Robert F; Thomas, Marvin L; Ayares, David; Horvath, Keith A

2014-09-01

Cardiac transplantation and available mechanical alternatives are the only possible solutions for end-stage cardiac disease. Unfortunately, because of the limited supply of human organs, xenotransplantation may be the ideal method to overcome this shortage. We have recently seen significant prolongation of heterotopic cardiac xenograft survival from 3 to 12 months and beyond. Hearts from genetically engineered piglets that were alpha 1-3 galactosidase transferase knockout and expressed the human complement regulatory gene, CD46 (groups A-C), and the human thrombomodulin gene (group D) were heterotropically transplanted in baboons treated with antithymocyte globulin, cobra venom factor, anti-CD20 antibody, and costimulation blockade (anti-CD154 antibody [clone 5C8]) in group A, anti-CD40 antibody (clone 3A8; 20 mg/kg) in group B, clone 2C10R4 (25 mg/kg) in group C, or clone 2C10R4 (50 mg/kg) in group D, along with conventional nonspecific immunosuppressive agents. Group A grafts (n = 8) survived for an average of 70 days, with the longest survival of 236 days. Some animals in this group (n = 3) developed microvascular thrombosis due to platelet activation and consumption, which resulted in spontaneous hemorrhage. The median survival time was 21 days in group B (n = 3), 80 days in group C (n = 6), and more than 200 days in group D (n = 5). Three grafts in group D are still contracting well, with the longest ongoing graft survival surpassing the 1-year mark. Genetically engineered pig hearts (GTKOhTg.hCD46.hTBM) with modified targeted immunosuppression (anti-CD40 monoclonal antibody) achieved long-term cardiac xenograft survival. This potentially paves the way for clinical xenotransplantation if similar survival can be reproduced in an orthotopic transplantation model. Copyright © 2014 The American Association for Thoracic Surgery. All rights reserved.

Molecular defects identified by whole exome sequencing in a child with Fanconi anemia.

PubMed

Zheng, Zhaojing; Geng, Juan; Yao, Ru-En; Li, Caihua; Ying, Daming; Shen, Yongnian; Ying, Lei; Yu, Yongguo; Fu, Qihua

2013-11-10

Fanconi anemia is a rare genetic disease characterized by bone marrow failure, multiple congenital malformations, and an increased susceptibility to malignancy. At least 15 genes have been identified that are involved in the pathogenesis of Fanconi anemia. However, it is still a challenge to assign the complementation group and to characterize the molecular defects in patients with Fanconi anemia. In the current study, whole exome sequencing was used to identify the affected gene(s) in a boy with Fanconi anemia. A recurring, non-synonymous mutation was found (c.3971C>T, p.P1324L) as well as a novel frameshift mutation (c.989_995del, p.H330LfsX2) in FANCA gene. Our results indicate that whole exome sequencing may be useful in clinical settings for rapid identification of disease-causing mutations in rare genetic disorders such as Fanconi anemia. © 2013 Elsevier B.V. All rights reserved.

Comprehensive approach to study complement C4 in systemic lupus erythematosus: Gene polymorphisms, protein levels and functional activity.

PubMed

Tsang-A-Sjoe, M W P; Bultink, I E M; Korswagen, L A; van der Horst, A; Rensink, I; de Boer, M; Hamann, D; Voskuyl, A E; Wouters, D

2017-12-01

Genetic variation of the genes encoding complement component C4 is strongly associated with systemic lupus erythematosus (SLE), a chronic multi-organ auto-immune disease. This study examined C4 and its isotypes on a genetic, protein, and functional level in 140 SLE patients and 104 healthy controls. Gene copy number (GCN) variation, silencing CT-insertion, and the retroviral HERV-K(C4) insertion) were analyzed with multiplex ligation-dependent probe amplification. Increased susceptibility to SLE was found for low GCN (≪2) of C4A. Serositis was the only clinical manifestation associated with low C4A GCN. One additional novel silencing mutation in the C4A gene was found by Sanger sequencing. This mutation causes a premature stop codon in exon 11. Protein concentrations of C4 isoforms C4A and C4B were determined with ELISA and were significantly lower in SLE patients compared to healthy controls. To study C4 isotypes on a functional level, a new C4 assay was developed, which distinguishes C4A from C4B by its binding capacity to amino or hydroxyl groups, respectively. This assay showed high correlation with ELISA and detected crossing over of Rodgers and Chido antigens in 3.2% (8/244) of individuals. The binding capacity of available C4 to its substrates was unaffected in SLE. Our study provides, for the first time, a complete overview of C4 in SLE from genetic variation to binding capacity using a novel test. As this test detects crossing over of Rodgers and Chido antigens, it will allow for more accurate measurement of C4 in future studies. Copyright © 2017 Elsevier Ltd. All rights reserved.

A second-generation genetic linkage map of the domestic dog, Canis familiaris.

PubMed Central

Neff, M W; Broman, K W; Mellersh, C S; Ray, K; Acland, G M; Aguirre, G D; Ziegle, J S; Ostrander, E A; Rine, J

1999-01-01

Purebred strains, pronounced phenotypic variation, and a high incidence of heritable disease make the domestic dog uniquely suited to complement genetic analyses in humans and mice. A comprehensive genetic linkage map would afford many opportunities in dogs, ranging from the positional cloning of disease genes to the dissection of quantitative differences in size, shape, and behavior. Here we report a canine linkage map with the number of mapped loci expanded to 276 and 10-cM coverage extended to 75-90% of the genome. Most of the 38 canine autosomes are likely represented in the collection of 39 autosomal linkage groups. Eight markers were sufficiently informative to detect linkage at distances of 10-13 cM, yet remained unlinked to any other marker. Taken together, the results suggested a genome size of about 27 M. As in other species, the genetic length varied between sexes, with the female autosomal distance being approximately 1.4-fold greater than that of male meioses. Fifteen markers anchored well-described genes on the map, thereby serving as landmarks for comparative mapping in dogs. We discuss the utility of the current map and outline steps necessary for future map improvement. PMID:9927471

21 CFR 866.5260 - Complement C3b inactivator immunological test system.

Code of Federal Regulations, 2011 CFR

2011-04-01

... immunochemical techniques the complement C3b inactivator (a plasma protein) in serum. Complement is a group of serum proteins that destroy infectious agents. Measurement of complement C3b inactivator aids in the...

21 CFR 866.5260 - Complement C3b inactivator immunological test system.

Code of Federal Regulations, 2014 CFR

2014-04-01

... immunochemical techniques the complement C3b inactivator (a plasma protein) in serum. Complement is a group of serum proteins that destroy infectious agents. Measurement of complement C3b inactivator aids in the...

21 CFR 866.5260 - Complement C3b inactivator immunological test system.

Code of Federal Regulations, 2013 CFR

2013-04-01

... immunochemical techniques the complement C3b inactivator (a plasma protein) in serum. Complement is a group of serum proteins that destroy infectious agents. Measurement of complement C3b inactivator aids in the...

21 CFR 866.5260 - Complement C3b inactivator immunological test system.

Code of Federal Regulations, 2012 CFR

2012-04-01

... immunochemical techniques the complement C3b inactivator (a plasma protein) in serum. Complement is a group of serum proteins that destroy infectious agents. Measurement of complement C3b inactivator aids in the...

Complement component 3 (C3)

MedlinePlus

... of a certain protein. This protein is part of the complement system. The complement system is a group of proteins ... system and play a role in the development of inflammation. The complement system protects the body from infections, dead cells and ...

Beyond main effects of gene-sets: harsh parenting moderates the association between a dopamine gene-set and child externalizing behavior.

PubMed

Windhorst, Dafna A; Mileva-Seitz, Viara R; Rippe, Ralph C A; Tiemeier, Henning; Jaddoe, Vincent W V; Verhulst, Frank C; van IJzendoorn, Marinus H; Bakermans-Kranenburg, Marian J

2016-08-01

In a longitudinal cohort study, we investigated the interplay of harsh parenting and genetic variation across a set of functionally related dopamine genes, in association with children's externalizing behavior. This is one of the first studies to employ gene-based and gene-set approaches in tests of Gene by Environment (G × E) effects on complex behavior. This approach can offer an important alternative or complement to candidate gene and genome-wide environmental interaction (GWEI) studies in the search for genetic variation underlying individual differences in behavior. Genetic variants in 12 autosomal dopaminergic genes were available in an ethnically homogenous part of a population-based cohort. Harsh parenting was assessed with maternal (n = 1881) and paternal (n = 1710) reports at age 3. Externalizing behavior was assessed with the Child Behavior Checklist (CBCL) at age 5 (71 ± 3.7 months). We conducted gene-set analyses of the association between variation in dopaminergic genes and externalizing behavior, stratified for harsh parenting. The association was statistically significant or approached significance for children without harsh parenting experiences, but was absent in the group with harsh parenting. Similarly, significant associations between single genes and externalizing behavior were only found in the group without harsh parenting. Effect sizes in the groups with and without harsh parenting did not differ significantly. Gene-environment interaction tests were conducted for individual genetic variants, resulting in two significant interaction effects (rs1497023 and rs4922132) after correction for multiple testing. Our findings are suggestive of G × E interplay, with associations between dopamine genes and externalizing behavior present in children without harsh parenting, but not in children with harsh parenting experiences. Harsh parenting may overrule the role of genetic factors in externalizing behavior. Gene-based and gene-set analyses offer promising new alternatives to analyses focusing on single candidate polymorphisms when examining the interplay between genetic and environmental factors.

Deep phenotyping of 89 xeroderma pigmentosum patients reveals unexpected heterogeneity dependent on the precise molecular defect

PubMed Central

Fassihi, Hiva; Sethi, Mieran; Fawcett, Heather; Wing, Jonathan; Chandler, Natalie; Mohammed, Shehla; Craythorne, Emma; Morley, Ana M. S.; Lim, Rongxuan; Turner, Sally; Henshaw, Tanya; Garrood, Isabel; Giunti, Paola; Hedderly, Tammy; Abiona, Adesoji; Naik, Harsha; Harrop, Gemma; McGibbon, David; Jaspers, Nicolaas G. J.; Botta, Elena; Nardo, Tiziana; Stefanini, Miria; Young, Antony R.; Sarkany, Robert P. E.; Lehmann, Alan R.

2016-01-01

Xeroderma pigmentosum (XP) is a rare DNA repair disorder characterized by increased susceptibility to UV radiation (UVR)-induced skin pigmentation, skin cancers, ocular surface disease, and, in some patients, sunburn and neurological degeneration. Genetically, it is assigned to eight complementation groups (XP-A to -G and variant). For the last 5 y, the UK national multidisciplinary XP service has provided follow-up for 89 XP patients, representing most of the XP patients in the United Kingdom. Causative mutations, DNA repair levels, and more than 60 clinical variables relating to dermatology, ophthalmology, and neurology have been measured, using scoring systems to categorize disease severity. This deep phenotyping has revealed unanticipated heterogeneity of clinical features, between and within complementation groups. Skin cancer is most common in XP-C, XP-E, and XP-V patients, previously considered to be the milder groups based on cellular analyses. These patients have normal sunburn reactions and are therefore diagnosed later and are less likely to adhere to UVR protection. XP-C patients are specifically hypersensitive to ocular damage, and XP-F and XP-G patients appear to be much less susceptible to skin cancer than other XP groups. Within XP groups, different mutations confer susceptibility or resistance to neurological damage. Our findings on this large cohort of XP patients under long-term follow-up reveal that XP is more heterogeneous than has previously been appreciated. Our data now enable provision of personalized prognostic information and management advice for each XP patient, as well as providing new insights into the functions of the XP proteins. PMID:26884178

Evaluating Secondary Students' Scientific Reasoning in Genetics Using a Two-Tier Diagnostic Instrument

NASA Astrophysics Data System (ADS)

Tsui, Chi-Yan; Treagust, David

2010-05-01

While genetics has remained as one key topic in school science, it continues to be conceptually and linguistically difficult for students with the concomitant debates as to what should be taught in the age of biotechnology. This article documents the development and implementation of a two-tier multiple-choice instrument for diagnosing grades 10 and 12 students' understanding of genetics in terms of reasoning. The pretest and posttest forms of the diagnostic instrument were used alongside other methods in evaluating students' understanding of genetics in a case-based qualitative study on teaching and learning with multiple representations in three Western Australian secondary schools. Previous studies have shown that a two-tier diagnostic instrument is useful in probing students' understanding or misunderstanding of scientific concepts and ideas. The diagnostic instrument in this study was designed and then progressively refined, improved, and implemented to evaluate student understanding of genetics in three case schools. The final version of the instrument had Cronbach's alpha reliability of 0.75 and 0.64, respectively, for its pretest and the posttest forms when it was administered to a group of grade 12 students (n = 17). This two-tier diagnostic instrument complemented other qualitative data collection methods in this research in generating a more holistic picture of student conceptual learning of genetics in terms of scientific reasoning. Implications of the findings of this study using the diagnostic instrument are discussed.

Protective immune responses against West Nile virus are primed by distinct complement activation pathways.

PubMed

Mehlhop, Erin; Diamond, Michael S

2006-05-15

West Nile virus (WNV) causes a severe infection of the central nervous system in several vertebrate animals including humans. Prior studies have shown that complement plays a critical role in controlling WNV infection in complement (C) 3(-/-) and complement receptor 1/2(-/-) mice. Here, we dissect the contributions of the individual complement activation pathways to the protection from WNV disease. Genetic deficiencies in C1q, C4, factor B, or factor D all resulted in increased mortality in mice, suggesting that all activation pathways function together to limit WNV spread. In the absence of alternative pathway complement activation, WNV disseminated into the central nervous system at earlier times and was associated with reduced CD8+ T cell responses yet near normal anti-WNV antibody profiles. Animals lacking the classical and lectin pathways had deficits in both B and T cell responses to WNV. Finally, and somewhat surprisingly, C1q was required for productive infection in the spleen but not for development of adaptive immune responses after WNV infection. Our results suggest that individual pathways of complement activation control WNV infection by priming adaptive immune responses through distinct mechanisms.

Chromosomal locations of the ribosomal dna genes in shortleaf pine

Treesearch

Narul Islam-Faridi; M. Abdul Majik; C. Dana Nelson

2007-01-01

A reference karyotype (i.e., chromosome-specific description of a species' chromosomal complement) is a pre-requisite for advanced genetic and genomic studies. The Southern Institute of Forest Genetics has initiated a project to develop reference karyotypes for each of the major southern U.S. pine species, including shortleaf pine, using AT-rich chromosomal...

QTL mapping for grain yield, flowering time, and stay-green traits in sorghum with genotyping-by-sequencing markers

USDA-ARS?s Scientific Manuscript database

Molecular breeding can complement traditional breeding approaches to achieve genetic gains in a more efficient way. In the present study, genetic mapping was conducted in a sorghum recombinant inbred line (RIL) population developed from Tx436 (a non-stay-green high food quality inbred) × 00MN7645 (a...

Genetic and cytogenetic analysis of the American cherry fruit fly, Rhagoletis cingulata (Diptera: Tephritidae).

PubMed

Drosopoulou, Elena; Augustinos, Antonios A; Nakou, Ifigeneia; Koeppler, Kirsten; Kounatidis, Ilias; Vogt, Heidrun; Papadopoulos, Nikolaos T; Bourtzis, Kostas; Mavragani-Tsipidou, Penelope

2011-12-01

The American eastern cherry fruit fly, Rhagoletis cingulata, a pest of cherries in the western hemisphere, invaded Europe in 1983, and since then dispersed to several European countries. Information on the genetics and cytogenetics of this pest is very scarce. The mitotic karyotype and detailed photographic maps of the salivary gland polytene chromosomes of R. cingulata are presented here. The mitotic metaphase complement consists of six pairs of chromosomes with the sex chromosomes being very small and similar in size. The analysis of the salivary gland polytene complement shows a total number of five long chromosomes (10 polytene arms), which correspond to the five autosomes of the mitotic nuclei and an extrachromosomal heterochromatic mass, which corresponds to the sex chromosomes. The banding patterns and the most characteristic features and prominent landmarks of each polytene chromosome are presented and discussed. Chromosomal homologies between R. cingulata, R. completa and R. cerasi are also proposed, based on the comparison of chromosome banding patterns. Furthermore, the detection and characterization of Wolbachia pipientis in the R. cingulata population studied is presented and the potential correlation with the asynaptic phenomena found in its polytene complement is discussed. In addition, 10 out of 24 microsatellite markers developed for other Rhagoletis species are cross-amplified, evaluated and proposed as useful markers for population and genetic studies in R. cingulata.

Complementation studies in Niemann-Pick disease type C indicate the existence of a second group.

PubMed Central

Steinberg, S J; Ward, C P; Fensom, A H

1994-01-01

Niemann-Pick disease type C is a clinically heterogeneous storage disorder with an unknown primary metabolic defect. We have undertaken somatic cell hybridisation experiments using skin fibroblast strains from 12 patients representing a wide clinical spectrum. Preliminary experiments using filipin staining of free cholesterol as a marker for complementation indicated the existence of one major group (group alpha) and one minor group (group beta) represented by one mutant strain. Subsequent experiments in which sphingomyelinase activity was measured as a marker for complementation using five mutant strains showing activity consistently < 40% control levels confirmed the existence of the second group. Images PMID:8071958

Alternative complement pathway activation increases mortality in a model of burn injury in mice.

PubMed Central

Gelfand, J A; Donelan, M; Hawiger, A; Burke, J F

1982-01-01

We have studied the role of the complement system in burn injury in an experimental model in mice. A 25% body surface area, full-thickness scald wound was produced in anesthetized animals. Massive activation of the alternative complement pathway, but not the classical pathway, was seen. This activation was associated with the generation of neutrophil aggregating activity in the plasma, neutrophil aggregates in the lungs, increased pulmonary vascular permeability, and increased lung edema formation. Decomplementation with cobra venom factor (CVF) or genetic C5 deficiency diminished these pathologic changes, and CVF pretreatment substantially reduced burn mortality in the first 24 h. Preliminary data show that human burn patients have a similar pattern of complement activation involving predominantly the alternative pathway, indicating the possible relevance of the murine model to human disease. Images PMID:7174787

Genetic diversity in a Poincianella pyramidalis (Tul.) L.P. Queiroz population assessed by RAPD molecular markers.

PubMed

Belarmino, K S; Rêgo, M M; Bruno, R L A; Medeiros, G D A; Andrade, A P; Rêgo, E R

2017-08-31

Poincianella pyramidalis (Tul.) L.P. Queiroz is an endemic Caatinga (Brazilian savannah biome) species that has been exploited for different purposes, although information is necessary about still existing natural populations. The objective of this study was to evaluate the genetic diversity among 20 P. pyramidalis individuals occurring in a population localized in the Caatinga biome of Paraíba State, aiming at seed collection, using RAPD markers. For the DNA extraction, young shoots of the individuals were used, and amplification was carried out using 20 primers. The obtained markers were converted to a binary matrix, from which a genetic dissimilarity matrix was built using the arithmetic complement of Jaccard's coefficient, and the dendrogram was built by the UPGMA analysis. No amplified fragment was monomorphic, resulting in 100% polymorphism of the analyzed population. The mean genetic diversity among the matrices was 63.28%, ranging from 30.9 to 97.7%. Individuals 09 and 17 showed relevant genetic proximity, and thus planting their seedlings at close sites would not be indicated. The population evaluated in this study showed high genetic diversity, originating twelve groups from the UPGMA hierarchical cluster analysis. Based on the results, individuals 09 and 17 can provide plant material for the evaluation of the physiological performance of P. pyramidalis seeds, and the set of individuals of this population has a high genetic diversity that characterizes them as adequate matrices for projects of restoration and conservation of the seed species.

Transient Receptor Potential Channel 6 (TRPC6) Protects Podocytes during Complement-mediated Glomerular Disease*

PubMed Central

Kistler, Andreas D.; Singh, Geetika; Altintas, Mehmet M.; Yu, Hao; Fernandez, Isabel C.; Gu, Changkyu; Wilson, Cory; Srivastava, Sandeep Kumar; Dietrich, Alexander; Walz, Katherina; Kerjaschki, Dontscho; Ruiz, Phillip; Dryer, Stuart; Sever, Sanja; Dinda, Amit K.; Faul, Christian; Reiser, Jochen

2013-01-01

Gain-of-function mutations in the calcium channel TRPC6 lead to autosomal dominant focal segmental glomerulosclerosis and podocyte expression of TRPC6 is increased in some acquired human glomerular diseases, particularly in membranous nephropathy. These observations led to the hypothesis that TRPC6 overactivation is deleterious to podocytes through pathological calcium signaling, both in genetic and acquired diseases. Here, we show that the effects of TRPC6 on podocyte function are context-dependent. Overexpression of TRPC6 alone did not directly affect podocyte morphology and cytoskeletal structure. Unexpectedly, however, overexpression of TRPC6 protected podocytes from complement-mediated injury, whereas genetic or pharmacological TRPC6 inactivation increased podocyte susceptibility to complement. Mechanistically, this effect was mediated by Ca2+/calmodulin-dependent protein kinase II (CaMKII) activation. Podocyte-specific TRPC6 transgenic mice showed stronger CaMKII activation, reduced podocyte foot process effacement and reduced levels of proteinuria during nephrotoxic serum nephritis, whereas TRPC6 null mice exhibited reduced CaMKII activation and higher levels of proteinuria compared with wild type littermates. Human membranous nephropathy biopsy samples showed podocyte staining for active CaMKII, which correlated with the degree of TRPC6 expression. Together, these data suggest a dual and context dependent role of TRPC6 in podocytes where acute activation protects from complement-mediated damage, but chronic overactivation leads to focal segmental glomerulosclerosis. PMID:24194522

Complement in Lupus Nephritis: New Perspectives.

PubMed

Bao, Lihua; Cunningham, Patrick N; Quigg, Richard J

2015-09-01

Systemic lupus erythematosus (SLE) is an autoimmune disorder caused by loss of tolerance to self-antigens, the production of autoantibodies and deposition of complement-fixing immune complexes (ICs) in injured tissues. SLE is characterized by a wide range of clinical manifestations and targeted organs, with lupus nephritis being one of the most serious complications. The complement system consists of three pathways and is tightly controlled by a set of regulatory proteins to prevent injudicious complement activation on host tissue. The involvement of the complement system in the pathogenesis of SLE is well accepted; yet, its exact role is still not clear. Complement plays dual roles in the pathogenesis of SLE. On the one hand, the complement system appears to have protective features in that hereditary homozygous deficiencies of classical pathway components, such as C1q and C4, are associated with an increased risk for SLE. On the other hand, IC-mediated activation of complement in affected tissues is clearly evident in both experimental and human SLE along with pathological features that are logical consequences of complement activation. Studies in genetically altered mice have shown that lack of complement inhibitors, such as complement factor H (CFH) or decay-accelerating factor (DAF) accelerates the development of experimental lupus nephritis, while treatment with recombinant protein inhibitors, such as Crry-Ig, CR2-Crry, CR2-DAF and CR2-CFH, ameliorates the disease development. Complement-targeted drugs, including soluble complement receptor 1 (TP10), C1 esterase inhibitor and a monoclonal anti-C5 antibody (eculizumab), have been shown to inhibit complement safely, and are now being investigated in a variety of clinical conditions. SLE is an autoimmune disorder which targets multiple systems. Complement is centrally involved and plays dual roles in the pathogenesis of SLE. Studies from experimental lupus models and clinical trials support the use of complement-targeted therapy in the treatment of SLE.

Gene for ataxia-telangiectasia complementation group D (ATDC)

DOEpatents

Murnane, John P.; Painter, Robert B.; Kapp, Leon N.; Yu, Loh-Chung

1995-03-07

Disclosed herein is a new gene, an AT gene for complementation group D, the ATDC gene and fragments thereof. Nucleic acid probes for said gene are provided as well as proteins encoded by said gene, cDNA therefrom, preferably a 3 kilobase (kb) cDNA, and recombinant nucleic acid molecules for expression of said proteins. Further disclosed are methods to detect mutations in said gene, preferably methods employing the polymerase chain reaction (PCR). Also disclosed are methods to detect AT genes from other AT complementation groups.

Evasion Mechanisms Used by Pathogens to Escape the Lectin Complement Pathway.

PubMed

Rosbjerg, Anne; Genster, Ninette; Pilely, Katrine; Garred, Peter

2017-01-01

The complement system is a crucial defensive network that protects the host against invading pathogens. It is part of the innate immune system and can be initiated via three pathways: the lectin, classical and alternative activation pathway. Overall the network compiles a group of recognition molecules that bind specific patterns on microbial surfaces, a group of associated proteases that initiates the complement cascade, and a group of proteins that interact in proteolytic complexes or the terminal pore-forming complex. In addition, various regulatory proteins are important for controlling the level of activity. The result is a pro-inflammatory response meant to combat foreign microbes. Microbial elimination is, however, not a straight forward procedure; pathogens have adapted to their environment by evolving a collection of evasion mechanisms that circumvent the human complement system. Complement evasion strategies features different ways of exploiting human complement proteins and moreover features different pathogen-derived proteins that interfere with the normal processes. Accumulated, these mechanisms target all three complement activation pathways as well as the final common part of the cascade. This review will cover the currently known lectin pathway evasion mechanisms and give examples of pathogens that operate these to increase their chance of invasion, survival and dissemination.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tuskan, Gerald

Jerry Tuskan of Oak Ridge National Laboratory and the DOE JGI talks about poplar trees as models for selective adaptation to an environment. This video complements a study published ahead online August 24, 2014 in Nature Genetics.

A Novel ‘Gene Insertion/Marker Out’ (GIMO) Method for Transgene Expression and Gene Complementation in Rodent Malaria Parasites

PubMed Central

Sajid, Mohammed; Chevalley-Maurel, Séverine; Ramesar, Jai; Klop, Onny; Franke-Fayard, Blandine M. D.; Janse, Chris J.; Khan, Shahid M.

2011-01-01

Research on the biology of malaria parasites has greatly benefited from the application of reverse genetic technologies, in particular through the analysis of gene deletion mutants and studies on transgenic parasites that express heterologous or mutated proteins. However, transfection in Plasmodium is limited by the paucity of drug-selectable markers that hampers subsequent genetic modification of the same mutant. We report the development of a novel ‘gene insertion/marker out’ (GIMO) method for two rodent malaria parasites, which uses negative selection to rapidly generate transgenic mutants ready for subsequent modifications. We have created reference mother lines for both P. berghei ANKA and P. yoelii 17XNL that serve as recipient parasites for GIMO-transfection. Compared to existing protocols GIMO-transfection greatly simplifies and speeds up the generation of mutants expressing heterologous proteins, free of drug-resistance genes, and requires far fewer laboratory animals. In addition we demonstrate that GIMO-transfection is also a simple and fast method for genetic complementation of mutants with a gene deletion or mutation. The implementation of GIMO-transfection procedures should greatly enhance Plasmodium reverse-genetic research. PMID:22216235

Functional analysis of the putative peroxidase domain of FANCA, the Fanconi anemia complementation group A protein.

PubMed

Ren, J; Youssoufian, H

2001-01-01

Fanconi anemia (FA) is an autosomal recessive disorder manifested by chromosomal breakage, birth defects, and susceptibility to bone marrow failure and cancer. At least seven complementation groups have been identified, and the genes defective in four groups have been cloned. The most common subtype is complementation group A. Although the normal functions of the gene products defective in FA cells are not completely understood, a clue to the function of the FA group A gene product (FANCA) was provided by the detection of limited homology in the amino terminal region to a class of heme peroxidases. We evaluated this hypothesis by mutagenesis and functional complementation studies. We substituted alanine residues for the most conserved FANCA residues in the putative peroxidase domain and tested their effects on known biochemical and cellular functions of FANCA. While the substitution mutants were comparable to wild-type FANCA with regard to their stability, subcellular localization, and interaction with FANCG, only the Trp(183)-to-Ala substitution (W183A) abolished the ability of FANCA to complement the sensitivity of FA group A cells to mitomycin C. By contrast, TUNEL assays for apoptosis after exposure to H2O2 showed no differences between parental FA group A cells, cells complemented with wild-type FANCA, and cells complemented with the W183A of FANCA. Moreover, semiquantitative RT-PCR analysis for the expression of the peroxide-sensitive heme oxygenase gene showed appropriate induction after H2O2 exposure. Thus, W183A appears to be essential for the in vivo activity of FANCA in a manner independent of its interaction with FANCG. Moreover, neither wild-type FANCA nor the W183A mutation appears to alter the peroxide-induced apoptosisor peroxide-sensing ability of FA group A cells. Copyright 2001 Academic Press.

TCP transcription factor, BRANCH ANGLE DEFECTIVE 1 (BAD1), is required for normal tassel branch angle formation in maize.

PubMed

Bai, Fang; Reinheimer, Renata; Durantini, Diego; Kellogg, Elizabeth A; Schmidt, Robert J

2012-07-24

In grass inflorescences, a structure called the "pulvinus" is found between the inflorescence main stem and lateral branches. The size of the pulvinus affects the angle of the lateral branches that emerge from the main axis and therefore has a large impact on inflorescence architecture. Through EMS mutagenesis we have identified three complementation groups of recessive mutants in maize having defects in pulvinus formation. All mutants showed extremely acute tassel branch angles accompanied by a significant reduction in the size of the pulvinus compared with normal plants. Two of the complementation groups correspond to mutations in the previously identified genes, RAMOSA2 (RA2) and LIGULELESS1 (LG1). Mutants corresponding to a third group were cloned using mapped-based approaches and found to encode a new member of the plant-specific TCP (TEOSINTE BRANCHED1/CYCLOIDEA/PROLIFERATING CELL NUCLEAR ANTIGEN FACTOR) family of DNA-binding proteins, BRANCH ANGLE DEFECTIVE 1 (BAD1). BAD1 is expressed in the developing pulvinus as well as in other developing tissues, including the tassels and juvenile leaves. Both molecular and genetics studies show that RA2 is upstream of BAD1, whereas LG1 may function in a separate pathway. Our findings demonstrate that BAD1 is a TCP class II gene that functions to promote cell proliferation in a lateral organ, the pulvinus, and influences inflorescence architecture by impacting the angle of lateral branch emergence.

Generation of EMS-Mutagenized Populations of Arabidopsis thaliana for Polyamine Genetics.

PubMed

Atanasov, Kostadin E; Liu, Changxin; Tiburcio, Antonio F; Alcázar, Rubén

2018-01-01

In the recent years, genetic engineering of polyamine biosynthetic genes has provided evidence for their involvement in plant stress responses and different aspects of plant development. Such approaches are being complemented with the use of reverse genetics, in which mutants affected on a particular trait, tightly associated with polyamines, are isolated and the causal genes mapped. Reverse genetics enables the identification of novel genes in the polyamine pathway, which may be involved in downstream signaling, transport, homeostasis, or perception. Here, we describe a basic protocol for the generation of ethyl methanesulfonate (EMS) mutagenized populations of Arabidopsis thaliana for its use in reverse genetics applied to polyamines.

Mannose-binding lectin binds to a range of clinically relevant microorganisms and promotes complement deposition.

PubMed

Neth, O; Jack, D L; Dodds, A W; Holzel, H; Klein, N J; Turner, M W

2000-02-01

Mannose-binding lectin (MBL) is a collagenous serum lectin believed to be of importance in innate immunity. Genetically determined low levels of the protein are known to predispose to infections. In this study the binding of purified MBL to pathogens isolated from immunocompromised children was investigated by flow cytometry. Diverse Candida species, Aspergillus fumigatus, Staphylococcus aureus, and beta-hemolytic group A streptococci exhibited strong binding of MBL, whereas Escherichia coli, Klebsiella species, and Haemophilus influenzae type b were characterized by heterogeneous binding patterns. In contrast, beta-hemolytic group B streptococci, Streptococcus pneumoniae, and Staphylococcus epidermidis showed low levels of binding. Bound MBL was able to promote C4 deposition in a concentration-dependent manner. We conclude that MBL may be of importance in first-line immune defense against several important pathogens.

Harvesting of novel polyhydroxyalkanaote (PHA) synthase encoding genes from a soil metagenome library using phenotypic screening.

PubMed

Schallmey, Marcus; Ly, Anh; Wang, Chunxia; Meglei, Gabriela; Voget, Sonja; Streit, Wolfgang R; Driscoll, Brian T; Charles, Trevor C

2011-08-01

We previously reported the construction of metagenomic libraries in the IncP cosmid vector pRK7813, enabling heterologous expression of these broad-host-range libraries in multiple bacterial hosts. Expressing these libraries in Sinorhizobium meliloti, we have successfully complemented associated phenotypes of polyhydroxyalkanoate synthesis mutants. DNA sequence analysis of three clones indicates that the complementing genes are homologous to, but substantially different from, known polyhydroxyalkanaote synthase-encoding genes. Thus we have demonstrated the ability to isolate diverse genes for polyhydroxyalkanaote synthesis by functional complementation of defined mutants. Such genes might be of use in the engineering of more efficient systems for the industrial production of bioplastics. The use of functional complementation will also provide a vehicle to probe the genetics of polyhydroxyalkanaote metabolism and its relation to carbon availability in complex microbial assemblages. 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

The Production of Complement Clauses in Children with Language Impairment

ERIC Educational Resources Information Center

Steel, Gillian; Rose, Miranda; Eadie, Patricia

2016-01-01

Purpose: The purpose of this research was to provide a comprehensive description of complement-clause production in children with language impairment. Complement clauses were examined with respect to types of complement structure produced, verb use, and both semantic and syntactic accuracy. Method: A group of 17 children with language impairment…

Dialysis in rats with acute renal failure: evaluation of three different dialyzer membranes.

PubMed

Kränzlin, B; Gretz, N; Kirschfink, M; Mujais, S K

1996-11-01

Exposure to complement-activating cellulosic dialysis membranes has been claimed to adversely affect the course of acute renal failure (ARF). To test this hypothesis, male Sprague-Dawley rats were allocated to 2 groups: in Group 1, ARF was induced by bilateral renal artery clamping whereas in Group 2, animals underwent a sham procedure. In each group, rats were further allocated to undergo hemodialysis with either a Cuprophan, a Hemophan, or a polyacrylonitrile minidialyzer on Days 4 and 8 after surgery, or no dialysis. Renal function was measured by inulin clearance on the days after dialysis. Additionally, total complement activity (CH50) was estimated on Days 1, 2, 4, and 8, and complement factor C3 was detected immunohistochemically. The degree of renal failure and the rate of recovery of renal function were similar in all the ARF groups irrespective of whether they had undergone dialysis or not, or of the type of the dialysis membrane. Furthermore, there were no significant differences in the course of CH50 or in the amount and distribution of complement factor C3 in the kidney tissue between the rats of Groups 1 and 2. Our findings refute the hypothesis that in ischemic ARF exposure to complement-activating cellulosic dialysis membranes impairs the recovery of renal function in rats.

Gene for ataxia-telangiectasia complementation group D (ATDC)

DOEpatents

Murnane, J.P.; Painter, R.B.; Kapp, L.N.; Yu, L.C.

1995-03-07

Disclosed herein is a new gene, an AT gene for complementation group D, the ATDC gene and fragments thereof. Nucleic acid probes for the gene are provided as well as proteins encoded by the gene, cDNA therefrom, preferably a 3 kilobase (kb) cDNA, and recombinant nucleic acid molecules for expression of the proteins. Further disclosed are methods to detect mutations in the gene, preferably methods employing the polymerase chain reaction (PCR). Also disclosed are methods to detect AT genes from other AT complementation groups. 30 figs.

Theory of mind in SLI revisited: links with syntax, comparisons with ASD.

PubMed

Durrleman, Stephanie; Burnel, Morgane; Reboul, Anne

2017-11-01

According to the linguistic determinism approach, knowledge of sentential complements such as: John says that the earth is flat plays a crucial role in theory of mind (ToM) development by providing a means to represent explicitly people's mental attitudes and beliefs. This approach predicts that mastery of complements determines successful belief reasoning across explicit ToM tasks, even low-verbal ones, and across populations. (1) To investigate the link between a low-verbal ToM-task and complements in Specific Language Impairment (SLI), (2) To determine whether this population shows similar ToM performance to that of children with Autism Spectrum Disorder (ASD) or those with Typical Development (TD) once these groups are matched on competency for complements, (3) To explore whether complements conveying a falsehood without jeopardizing the veracity of the entire sentence, such as complements of verbs of communication, are more crucial for belief attribution than complements which do not have this property, namely complements of verbs of perception, (?John sees that the earth is flat). Children with SLI (n = 20), with ASD (n = 34) and TD (n = 30) completed sentence-picture-matching tasks assessing complementation with communication and perception verbs, as well as a picture-sequencing task assessing ToM. Children were furthermore evaluated for general grammatical and lexical abilities and non-verbal IQ. Results reveal that competency on complements relates to ToM performance with a low-verbal task in SLI, and that SLI, ASD and TD groups of equivalent performance on complements also perform similarly for ToM. Results further suggest that complements with an independent truth-value are the only ones to show a significant relation to ToM performance after teasing out the impact of non-verbal reasoning. This study suggests that clinical groups of different aetiologies as well as TD children perform comparably for ToM once they have similar complementation skills. Findings further highlight that specific types of complements, namely those with an independent truth value, relate in a special way to mentalizing. Future work should determine whether these specific structures could be effective in ToM remediation programmes. © 2017 Royal College of Speech and Language Therapists.

Population genetic analysis of a global collection of Fragaria vesca using microsatellite markers

PubMed Central

Hilmarsson, Hrannar Smári; Hytönen, Timo; Isobe, Sachiko; Göransson, Magnus; Toivainen, Tuomas

2017-01-01

The woodland strawberry, Fragaria vesca, holds great promise as a model organism. It not only represents the important Rosaceae family that includes economically important species such as apples, pears, peaches and roses, but it also complements the well-known model organism Arabidopsis thaliana in key areas such as perennial life cycle and the development of fleshy fruit. Analysis of wild populations of A. thaliana has shed light on several important developmental pathways controlling, for example, flowering time and plant growth, suggesting that a similar approach using F. vesca might add to our understanding on the development of rosaceous species and perennials in general. As a first step, 298 F. vesca plants were analyzed using microsatellite markers with the primary aim of analyzing population structure and distribution of genetic diversity. Of the 68 markers tested, 56 were polymorphic, with an average of 4.46 alleles per locus. Our analysis partly confirms previous classification of F. vesca subspecies in North America and suggests two groups within the subsp. bracteata. In addition, F. vesca subsp. vesca forms a single global population with evidence that the Icelandic group is a separate cluster from the main Eurasian population. PMID:28854285

Population genetic analysis of a global collection of Fragaria vesca using microsatellite markers.

PubMed

Hilmarsson, Hrannar Smári; Hytönen, Timo; Isobe, Sachiko; Göransson, Magnus; Toivainen, Tuomas; Hallsson, Jón Hallsteinn

2017-01-01

The woodland strawberry, Fragaria vesca, holds great promise as a model organism. It not only represents the important Rosaceae family that includes economically important species such as apples, pears, peaches and roses, but it also complements the well-known model organism Arabidopsis thaliana in key areas such as perennial life cycle and the development of fleshy fruit. Analysis of wild populations of A. thaliana has shed light on several important developmental pathways controlling, for example, flowering time and plant growth, suggesting that a similar approach using F. vesca might add to our understanding on the development of rosaceous species and perennials in general. As a first step, 298 F. vesca plants were analyzed using microsatellite markers with the primary aim of analyzing population structure and distribution of genetic diversity. Of the 68 markers tested, 56 were polymorphic, with an average of 4.46 alleles per locus. Our analysis partly confirms previous classification of F. vesca subspecies in North America and suggests two groups within the subsp. bracteata. In addition, F. vesca subsp. vesca forms a single global population with evidence that the Icelandic group is a separate cluster from the main Eurasian population.

Evasion Mechanisms Used by Pathogens to Escape the Lectin Complement Pathway

PubMed Central

Rosbjerg, Anne; Genster, Ninette; Pilely, Katrine; Garred, Peter

2017-01-01

The complement system is a crucial defensive network that protects the host against invading pathogens. It is part of the innate immune system and can be initiated via three pathways: the lectin, classical and alternative activation pathway. Overall the network compiles a group of recognition molecules that bind specific patterns on microbial surfaces, a group of associated proteases that initiates the complement cascade, and a group of proteins that interact in proteolytic complexes or the terminal pore-forming complex. In addition, various regulatory proteins are important for controlling the level of activity. The result is a pro-inflammatory response meant to combat foreign microbes. Microbial elimination is, however, not a straight forward procedure; pathogens have adapted to their environment by evolving a collection of evasion mechanisms that circumvent the human complement system. Complement evasion strategies features different ways of exploiting human complement proteins and moreover features different pathogen-derived proteins that interfere with the normal processes. Accumulated, these mechanisms target all three complement activation pathways as well as the final common part of the cascade. This review will cover the currently known lectin pathway evasion mechanisms and give examples of pathogens that operate these to increase their chance of invasion, survival and dissemination. PMID:28553281

Inhibitor(s) of the classical complement pathway in mouse serum limit the utility of mice as experimental models of neuromyelitis optica.

PubMed

Ratelade, Julien; Verkman, A S

2014-11-01

Neuromyelitis optica (NMO) is an inflammatory demyelinating disease of the central nervous system in which anti-aquaporin-4 (AQP4) autoantibodies (AQP4-IgG) cause damage to astrocytes by complement-dependent cytotoxicity (CDC). Various approaches have been attempted to produce NMO lesions in rodents, some involving genetically modified mice with altered immune cell function. Here, we found that mouse serum strongly inhibits complement from multiple species, preventing AQP4-IgG-dependent CDC. Effects of mouse serum on complement activation were tested in CDC assays in which AQP4-expressing cells were incubated with AQP4-IgG and complement from different species. Biochemical assays and mass spectrometry were used to characterize complement inhibitor(s) in mouse serum. Sera from different strains of mice produced almost no AQP4-IgG-dependent CDC compared with human, rat and guinea pig sera. Remarkably, addition of mouse serum prevented AQP4-IgG-dependent CDC caused by human, rat or guinea pig serum, with 50% inhibition at <5% mouse serum. Hemolysis assays indicated that the inhibitor(s) in mouse serum target the classical and not the alternative complement pathway. We found that the complement inhibitor(s) in mouse serum were contained in a serum fraction purified with protein-A resin; however, the inhibitor was not IgG as determined using serum from IgG-deficient mice. Mass spectrometry on the protein A-purified fraction produced several inhibitor candidates. The low intrinsic complement activity of mouse serum and the presence of complement inhibitor(s) limit the utility of mouse models to study disorders, such as NMO, involving the classical complement pathway. Copyright © 2014 Elsevier Ltd. All rights reserved.

Preeclampsia in autologous and oocyte donation pregnancy: is there a different pathophysiology?

PubMed

Lashley, Lisa E E L O; Buurma, Aletta; Swings, Godelieve M J S; Eikmans, Michael; Anholts, Jacqueline D H; Bakker, Jaap A; Claas, Frans H J

2015-06-01

Oocyte donation (OD) is a specific method of artificial reproductive technology that is accompanied by a higher risk of preeclampsia during pregnancy. The pathophysiological mechanism underlying preeclampsia in OD pregnancies is thought to differ from preeclampsia in autologous pregnancies. As preeclampsia in autologous pregnancies is suggested to be associated with complement activation, we studied C4d deposition, circulating complement components and placental complement regulatory proteins in preeclamptic OD pregnancies. Women with uncomplicated and preeclamptic pregnancies after OD or spontaneous conception were selected. We stained the placentas for C4d, marker for complement activation, measured complement factors C1q, C3 and C4 in maternal sera and quantified the placental mRNA expression of complement regulatory proteins CD46, CD55 and CD59. A significantly (p < 0.03) higher incidence of C4d deposition was observed in placentas from women with preeclampsia compared with uncomplicated pregnancies, both OD and autologous. The level of complement factors in serum did not differ between the groups. Children born in the autologous preeclampsia group were significantly lower in birth weight (p < 10th percentile) compared with the preeclamptic OD group. In addition, the placental mRNA expression level of complement regulatory proteins was significantly lower in uncomplicated and preeclamptic OD compared with the autologous pregnancies. In line with autologous preeclampsia pregnancies, there is excessive activation of complement in preeclamptic OD pregnancies. However, in contrast to autologous pregnancies this is not associated with counterbalancing upregulation of complement regulatory proteins. Furthermore, C4d deposition in OD pregnancies is not related to the severity of preeclampsia, suggesting another trigger or regulatory mechanism of placental C4d deposition in preeclamptic OD pregnancies. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

An ultra-high-density map as a community resource for discerning the genetic basis of quantitative traits in maize

USDA-ARS?s Scientific Manuscript database

In this study, we generated a linkage map containing 1,151,856 high quality SNPs between Mo17 and B73, which were verified in the maize intermated B73'×'Mo17 (IBM) Syn10 population. This resource is an excellent complement to existing maize genetic maps available in an online database (iPlant, http:...

How well do you know your mutation? Complex effects of genetic background on expressivity, complementation, and ordering of allelic effects

PubMed Central

Choi, Lin; DeNieu, Michael; Sonnenschein, Anne; Hummel, Kristen; Marier, Christian; Victory, Andrew; Porter, Cody; Mammel, Anna; Holms, Julie; Sivaratnam, Gayatri

2017-01-01

For a given gene, different mutations influence organismal phenotypes to varying degrees. However, the expressivity of these variants not only depends on the DNA lesion associated with the mutation, but also on factors including the genetic background and rearing environment. The degree to which these factors influence related alleles, genes, or pathways similarly, and whether similar developmental mechanisms underlie variation in the expressivity of a single allele across conditions and among alleles is poorly understood. Besides their fundamental biological significance, these questions have important implications for the interpretation of functional genetic analyses, for example, if these factors alter the ordering of allelic series or patterns of complementation. We examined the impact of genetic background and rearing environment for a series of mutations spanning the range of phenotypic effects for both the scalloped and vestigial genes, which influence wing development in Drosophila melanogaster. Genetic background and rearing environment influenced the phenotypic outcome of mutations, including intra-genic interactions, particularly for mutations of moderate expressivity. We examined whether cellular correlates (such as cell proliferation during development) of these phenotypic effects matched the observed phenotypic outcome. While cell proliferation decreased with mutations of increasingly severe effects, surprisingly it did not co-vary strongly with the degree of background dependence. We discuss these findings and propose a phenomenological model to aid in understanding the biology of genes, and how this influences our interpretation of allelic effects in genetic analysis. PMID:29166655

Genetics of hemolytic uremic syndromes.

PubMed

Malina, Michal; Roumenina, Lubka T; Seeman, Tomáš; Le Quintrec, Moglie; Dragon-Durey, Marie-Agnes; Schaefer, Franz; Fremeaux-Bacchi, Véronique

2012-03-01

Hemolytic uremic syndrome (HUS) is a very rare disease (two cases per year per 1 million population) but represents the most common cause of acute renal failure in young children that require dialysis. The majority of cases in childhood (90%) is caused by Shiga toxin producing Escherichia coli infection. This typical form of the disease does not relapse and has a good prognosis if the acute status can be managed successfully. Atypical HUS (aHUS) is a severe and frequently relapsing disorder with the same triad of thrombocytopenia, hemolysis and acute renal failure in the absence of Shiga toxin E. coli infection. More than 50% of patients with atypical HUS progress to chronic renal dysfunction and 10% die due to complications of the disease. Atypical HUS appears to have a genetic basis. Mutations in genes coding for components of the alternative complement pathway are found in about 60% of cases. The clinical presentation of aHUS overlaps with that of other thrombotic microangiopathies, rendering the diagnosis on clinical grounds alone extremely difficult. In recent years, genetic testing has opened the way for molecular diagnostics and helped establishing therapeutically and prognostically useful genotype-phenotype correlations. This review summarizes recent findings regarding the genetic basis of the HUS. The pathophysiology of the disease and the implication of genetic abnormalities in the complement system for the different types of HUS are discussed. Copyright © 2012. Published by Elsevier Masson SAS.

Isolation, characterization, and genetic complementation of a cellular mutant resistant to retroviral infection

PubMed Central

Agarwal, Sumit; Harada, Josephine; Schreifels, Jeffrey; Lech, Patrycja; Nikolai, Bryan; Yamaguchi, Tomoyuki; Chanda, Sumit K.; Somia, Nikunj V.

2006-01-01

By using a genetic screen, we have isolated a mammalian cell line that is resistant to infection by retroviruses that are derived from the murine leukemia virus, human immunodeficiency virus type 1, and feline immunodeficiency virus. We demonstrate that the cell line is genetically recessive for the resistance, and hence it is lacking a factor enabling infection by retroviruses. The block to infection is early in the life cycle, at the poorly understood uncoating stage. We implicate the proteasome at uncoating by completely rescuing the resistant phenotype with the proteasomal inhibitor MG-132. We further report on the complementation cloning of a gene (MRI, modulator of retrovirus infection) that can also act to reverse the inhibition of infection in the mutant cell line. These data implicate a role for the proteasome during uncoating, and they suggest that MRI is a regulator of this activity. Finally, we reconcile our findings and other published data to suggest a model for the involvement of the proteasome in the early phase of the retroviral life cycle. PMID:17043244

Novel homozygous FANCL mutation and somatic heterozygous SETBP1 mutation in a Chinese girl with Fanconi Anemia.

PubMed

Wu, Weiqing; Liu, Yang; Zhou, Qinghua; Wang, Qin; Luo, Fuwei; Xu, Zhiyong; Geng, Qian; Li, Peining; Zhang, Hui Z; Xie, Jiansheng

2017-07-01

Fanconi Anemia (FA) is a rare genetically heterogeneous disorder with 17 known complement groups caused by mutations in different genes. FA complementation group L (FA-L, OMIM #608111) occurred in 0.2% of all FA and only eight mutant variants in the FANCL gene were documented. Phenotype and genotype correlation in FANCL associated FA is still obscure. Here we describe a Chinese girl with FA-L caused by a novel homozygous mutation c.822_823insCTTTCAGG (p.Asp275LeufsX13) in the FANCL gene. The patient's clinical course was typical for FA with progression to bone marrow failure, and death from acute myelomonocytic leukemia (AML-M4) at 9 years of age. Mutation analysis also detected a likely somatic c.2608G > A (p.Gly870Ser) in the SETBP1 gene. Consistent copy number losses of 7q and 18p and gains of 3q and 21q and accumulated non-clonal single cell chromosomal abnormalities were detected in blood leukocytes as her FA progressed. This is the first Chinese FA-L case caused by a novel FANCL mutation. The somatic gene mutation and copy number aberrations could be used to monitor disease progression and the clinical findings provide further information for genotype-phenotype correlation for FA-L. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Twenty-First Century Diseases: Commonly Rare and Rarely Common?

PubMed

Daunert, Sylvia; Sittampalam, Gurusingham Sitta; Goldschmidt-Clermont, Pascal J

2017-09-20

Alzheimer's drugs are failing at a rate of 99.6%, and success rate for drugs designed to help patients with this form of dementia is 47 times less than for drugs designed to help patients with cancers ( www.scientificamerican.com/article/why-alzheimer-s-drugs-keep-failing/2014 ). How can it be so difficult to produce a valuable drug for Alzheimer's disease? Each human has a unique genetic and epigenetic makeup, thus endowing individuals with a highly unique complement of genes, polymorphisms, mutations, RNAs, proteins, lipids, and complex sugars, resulting in distinct genome, proteome, metabolome, and also microbiome identity. This editorial is taking into account the uniqueness of each individual and surrounding environment, and stresses the point that a more accurate definition of a "common" disorder could be simply the amalgamation of a myriad of "rare" diseases. These rare diseases are being grouped together because they share a rather constant complement of common features and, indeed, generally respond to empirically developed treatments, leading to a positive outcome consistently. We make the case that it is highly unlikely that such treatments, despite their statistical success measured with large cohorts using standardized clinical research, will be effective on all patients until we increase the depth and fidelity of our understanding of the individual "rare" diseases that are grouped together in the "buckets" of common illnesses. Antioxid. Redox Signal. 27, 511-516.

Worldwide Distribution of Four SNPs in X‐Ray and Repair and Cross‐Complementing Group 1 (XRCC1)

PubMed Central

Takeshita, Haruo; Yasuda, Toshihiro; Kimura‐Kataoka, Kaori

2014-01-01

Abstract Purpose X‐ray repair cross‐complementing group 1 (XRCC1) repairs single‐strand breaks in DNA. Several reports have shown the association of single nucleotide polymorphisms (SNPs) (Arg194Trp, Pro206Pro, Arg280His, Arg399Gln) in XRCC1 to diseases. Limited population data are available regarding SNPs in XRCC1, especially in African populations. In this study, genotype distributions of four SNPs in worldwide populations were examined and compared with those reported previously. Materials and Methods Four SNPs (Arg194Trp, Pro206Pro, Arg280His, Arg399Gln) in XRCC1 from genomic DNA samples of 10 populations were evaluated by using polymerase chain reaction followed by restriction fragment length polymorphism analysis. Results The frequency of the minor allele corresponding to the Trp allele of XRCC1Arg194Trp was higher in Asian populations than in African and Caucasian populations. As for XRCC1Pro206Pro, Africans showed higher minor allele frequencies than did Asian populations, except for Tamils and Sinhalese. XRCC1 Arg280His frequencies were similar among Africans and Caucasians but differed among Asian populations. Similarly, lower mutant XRCC1 Arg399Gln frequencies were observed in Africans. Conclusions This study is the first to show the existence of a certain genetic heterogeneity in the worldwide distribution of four SNPs in XRCC1. PMID:25387884

Association studies of excision repair cross-complementation group 1 (ERCC1) haplotypes with lung and head and neck cancer risk in a Caucasian population.

PubMed

Jones, Nathan R; Spratt, Thomas E; Berg, Arthur S; Muscat, Joshua E; Lazarus, Philip; Gallagher, Carla J

2011-04-01

The formation of bulky DNA adducts caused by diol epoxide derivatives of polycyclic aromatic hydrocarbons has been associated with tobacco-induced cancers, and inefficient repair of such adducts by the nucleotide excision repair (NER) system has been linked to increased risk of tobacco-induced lung and head and neck (H&N) cancers. The human excision repair cross-complementation group 1 (ERCC1) protein is essential for a functional NER system and genetic variation in ERCC1 may contribute to impaired DNA repair capacity and increased lung and H&N cancer risk. In order to comprehensively capture common genetic variation in the ERCC1 gene, Caucasian data from the International HapMap project was used to assess linkage disequilibrium and choose four tagSNPs (rs1319052, rs3212955, rs3212948, and rs735482) in the ERCC1 gene to genotype 452 lung cancer cases, 175 H&N cancer cases, and 790 healthy controls. Haplotypes were estimated using expectation maximization (EM) algorithm, and haplotype association with cancer was investigated using Haplo.stats software adjusting for known covariates. The genotype and haplotype frequencies matched previous estimates from Caucasians. There was no significant difference in the prevalence of rs1319052, rs3212955, rs3212948, and rs735482 when comparing lung or H&N cancer cases with controls (p-values>0.05). Similarly, there was no association between ERCC1 haplotypes and lung or H&N cancer susceptibility in this Caucasian population (p-values>0.05). No associations were found when stratifying lung cancer cases by histology, sex, smoking status, or smoking intensity. This study suggests that ERCC1 polymorphisms and haplotypes do not play a role in lung and H&N cancer susceptibility in Caucasians. Copyright © 2010 Elsevier Ltd. All rights reserved.

Association of genetic polymorphisms in ERCC1 and ERCC2/XPD with risk of chronic benzene poisoning in a Chinese occupational population.

PubMed

Xiao, Sha; Gao, Lin; Liu, Yanhua; Yu, Tao; Jin, Cuihong; Pan, Liang; Zhu, Guolian; Lu, Xiaobo

2013-02-18

DNA damage induced by benzene and its metabolites is thought of as an important mechanism underlying benzene genotoxicity in chronic benzene poisoning (CBP). Therefore, genetic variation in DNA repair genes may contribute to susceptibility to CBP in the exposed population. Since benzene-induced DNA damages include DNA adducts, we hypothesized that the polymorphisms of ERCC1 (Excision repair cross complementation group 1) and ERCC2/XPD (Excision repair cross complementation group 2/xeroderma pigmentosum group D) are associated with the risk of CBP. A case-control study involving 102 benzene-poisoned patients and 204 none-benzene-poisoned controls occupationally exposed to benzene was carried out in the Northeast region of China. The polymorphisms of codon 118 (rs11615) and C8092A (rs3212986) of ERCC1, codon 751 (rs13181), 312 (rs1799793) and 156 (rs238406) of ERCC2/XPD were genotyped by TaqMan(®) Real-time PCR. The results showed that individuals carrying the ERCC1 codon 118 TT genotype had an increased risk of CBP (OR(adj)=3.390; 95%CI: 1.393-8.253; P=0.007) comparing with its CC genotype. After stratified by smoking, gender and exposure duration we found that the increased risk of CBP associated with the ERCC1 codon 118 TT genotype confined to nonsmokers (OR=3.214; 95% CI: 1.359-7.601; P=0.006), female (OR=3.049; 95% CI: 1.235-7.529; P=0.013) and exposure duration> 12 years (OR=3.750; 95% CI: 1.041-13.513; P=0.035). Since ERCC1 and ERCC2/XPD are both located on chromosome 19q13.3, haplotype analysis of all 5 SNPs was also conducted. However no correlations between the risks of CBP and other genotypes or haplotypes were found. Therefore, our findings suggest an important role of ERCC1 codon 118 polymorphisms for a biomarker to CBP in the Chinese occupational population. Copyright © 2012 Elsevier B.V. All rights reserved.

Strains Responsible for Invasive Meningococcal Disease in Patients With Terminal Complement Pathway Deficiencies.

PubMed

Rosain, Jérémie; Hong, Eva; Fieschi, Claire; Martins, Paula Vieira; El Sissy, Carine; Deghmane, Ala-Eddine; Ouachée, Marie; Thomas, Caroline; Launay, David; de Pontual, Loïc; Suarez, Felipe; Moshous, Despina; Picard, Capucine; Taha, Muhamed-Kheir; Frémeaux-Bacchi, Véronique

2017-04-15

Patients with terminal complement pathway deficiency (TPD) are susceptible to recurrent invasive meningococcal disease (IMD). Neisseria meningitidis (Nm) strains infecting these patients are poorly documented in the literature. We identified patients with TPD and available Nm strains isolated during IMD. We investigated the genetic basis of the different TPDs and the characteristics of the Nm strains. We included 56 patients with C5 (n = 8), C6 (n = 20), C7 (n = 18), C8 (n = 9), or C9 (n = 1) deficiency. Genetic study was performed in 47 patients and 30 pathogenic variants were identified in the genes coding for C5 (n = 4), C6 (n = 5), C7 (n = 12), C8 (n = 7), and C9 (n = 2). We characterized 61 Nm strains responsible for IMD in the 56 patients with TPD. The most frequent strains belonged to groups Y (n = 27 [44%]), B (n = 18 [30%]), and W (n = 8 [13%]). Hyperinvasive clonal complexes (CC11, CC32, CC41/44, and CC269) were responsible for 21% of IMD cases. The CC23 predominates and represented 26% of all invasive isolates. Eleven of the 15 clonal complexes identified fit to 12 different clonal complexes belonging to carriage strains. Unusual meningococcal strains with low level of virulence similar to carriage strains are most frequently responsible for IMD in patients with TPD. © The Author 217. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

Saccharomyces cerevisiae mutants with enhanced induced mutation and altered mitotic gene conversion.

PubMed

Ivanov, E L; Kovaltzova, S V; Korolev, V G

1989-08-01

We have developed a method to isolate yeast (Saccharomyces cerevisiae) mutants with enhanced induced mutagenesis based on nitrous acid-induced reversion of the ade2-42 allele. Six mutants have been isolated and designated him (high induced mutagenesis), and 4 of them were studied in more detail. The him mutants displayed enhanced reversion of the ade2-42 allele, either spontaneous or induced by nitrous acid, UV light, and the base analog 6-N-hydroxylaminopurine, but not by gamma-irradiation. It is worth noting that the him mutants turned out not to be sensitive to the lethal effects of the mutagens used. The enhancement in mutation induced by nitrous acid, UV light, and 6-N-hydroxylaminopurine has been confirmed in a forward-mutation assay (induction of mutations in the ADE1, ADE2 genes). The latter agent revealed the most apparent differences between the him mutants and the wild-type strain and was, therefore, chosen for the genetic analysis of mutants, him mutations analyzed behaved as a single Mendelian trait; complementation tests indicated 3 complementation groups (HIM1, HIM2, and HIM3), each containing 1 mutant allele. Uracil-DNA glycosylase activity was determined in crude cell extracts, and no significant differences between the wild-type and him strains were detected. Spontaneous mitotic gene conversion at the ADE2 locus is altered in him1 strains, either increased or decreased, depending on the particular heteroallelic combination. Genetic evidence strongly suggests him mutations to be involved in a process of mismatch correction of molecular heteroduplexes.

Finding Fingerprints of Selection in Poplar Genomes

ScienceCinema

Tuskan, Gerald

2018-05-30

Jerry Tuskan of Oak Ridge National Laboratory and the DOE JGI talks about poplar trees as models for selective adaptation to an environment. This video complements a study published ahead online August 24, 2014 in Nature Genetics.

Transgenic horticultural crops in Asia

USDA-ARS?s Scientific Manuscript database

Modern biotechnology applications, including genetic engineering, are a powerful tool to complement the conventional methods of crop improvement. Asia currently has three countries cultivating biotech/transgenic crops – China, India, and the Philippines, but only China commercially grows a transgen...

Genetic manipulation of the obligate chemolithoautotrophic bacterium Thiobacillus denitrificans

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beller, H.R.; Legler, T.C.; Kane, S.R.

2011-07-15

Chemolithoautotrophic bacteria can be of industrial and environmental importance, but they present a challenge for systems biology studies, as their central metabolism deviates from that of model organisms and there is a much less extensive experimental basis for their gene annotation than for typical organoheterotrophs. For microbes with sequenced genomes but unconventional metabolism, the ability to create knockout mutations can be a powerful tool for functional genomics and thereby render an organism more amenable to systems biology approaches. In this chapter, we describe a genetic system for Thiobacillus denitrificans, with which insertion mutations can be introduced by homologous recombination andmore » complemented in trans. Insertion mutations are generated by in vitro transposition, the mutated genes are amplified by the PCR, and the amplicons are introduced into T. denitrificans by electroporation. Use of a complementation vector, pTL2, based on the IncP plasmid pRR10 is also addressed.« less

A Nonsense Mutation in Mycobacterium marinum That Is Suppressible by a Novel Mechanism

PubMed Central

Williams, Emily A.; Mba Medie, Felix; Bosserman, Rachel E.; Johnson, Benjamin K.; Reyna, Cristal; Ferrell, Micah J.; Champion, Matthew M.; Abramovitch, Robert B.

2016-01-01

ABSTRACT Mycobacterial pathogens use the ESAT-6 system 1 (Esx-1) exporter to promote virulence. Previously, we used gene disruption and complementation to conclude that the MMAR_0039 gene in Mycobacterium marinum is required to promote Esx-1 export. Here we applied molecular genetics, proteomics, and whole-genome sequencing to demonstrate that the MMAR_0039 gene is not required for Esx-1 secretion or virulence. These findings suggest that we initially observed an indirect mechanism of genetic complementation. We identified a spontaneous nonsense mutation in a known Esx-1-associated gene which causes a loss of Esx-1 activity. We show that the Esx-1 function was restored by nonsense suppression. Moreover, we identified a polar mutation in the ppsC gene which reduced cellular impermeability but did not impact cytotoxicity in macrophages. Our studies reveal insight into Esx-1 export, nonsense suppression, and cell envelope lipid biogenesis. PMID:27789543

Isolation of a complementary DNA clone for the human complement protein C2 and its use in the identification of a restriction fragment length polymorphism.

PubMed Central

Woods, D E; Edge, M D; Colten, H R

1984-01-01

Complementary DNA (cDNA) clones corresponding to the major histocompatibility (MHC) class III antigen, complement protein C2, have been isolated from human liver cDNA libraries with the use of a complex mixture of synthetic oligonucleotides (17 mer) that contains 576 different oligonucleotide sequences. The C2 cDNA were used to identify a DNA restriction enzyme fragment length polymorphism that provides a genetic marker within the MHC that was not detectable at the protein level. An extensive search for genomic polymorphisms using a cDNA clone for another MHC class III gene, factor B, failed to reveal any DNA variants. The genomic variants detected with the C2 cDNA probe provide an additional genetic marker for analysis of MHC-linked diseases. Images PMID:6086718

Polymorphisms within the FANCA gene associate with premature ovarian failure in Korean women.

PubMed

Pyun, Jung-A; Kim, Sunshin; Cha, Dong Hyun; Kwack, KyuBum

2014-05-01

This study investigated whether polymorphisms within the Fanconi anemia complementation group A (FANCA) gene contribute to the increased risk of premature ovarian failure (POF) in Korean women. Ninety-eight women with POF and 218 controls participated in this study. Genomic DNA from peripheral blood was isolated, and GoldenGate genotyping assay was used to identify single nucleotide polymorphisms (SNPs) within the FANCA gene. Two significant SNPs (rs1006547 and rs2239359; P < 0.05) were identified by logistic regression analysis, but results were insignificant after Bonferroni correction. Six SNPs formed a linkage disequilibrium block, and three main haplotypes were found. Two of three haplotypes (AAAGAA and GGGAGG) distributed highly in the POF group, whereas the remaining haplotype (GGAAGG) distributed highly in the control group by logistic regression analysis (highest odds ratio, 2.515; 95% CI, 1.515-4.175; P = 0.00036). Our observations suggest that genetic variations in the FANCA gene may increase the risk for POF in Korean women.

Establishment of a molecular genetic map of distal mouse chromosome 1: further definition of a conserved linkage group syntenic with human chromosome 1q.

PubMed

Seldin, M F; Morse, H C; LeBoeuf, R C; Steinberg, A D

1988-01-01

A linkage map of distal mouse chromosome 1 was constructed by restriction fragment length polymorphism analysis of DNAs from seven sets of recombinant inbred (RI) strains. The data obtained with seven probes on Southern hybridization combined with data from previous studies suggest the gene order Cfh, Pep-3/Ren-1,2, Ly-5, Lamb-2, At-3, Apoa-2/Ly-17,Spna-1. These results confirm and extend analyses of a large linkage group which includes genes present on a 20-30 cM span of mouse chromosome 1 and those localized to human chromosome 1q21-32. Moreover, the data indicate similar relative positions of human and mouse complement receptor-related genes REN, CD45, LAMB2, AT3, APOA2, and SPTA. These results suggest that mouse gene analyses may help in detailed mapping of human genes within such a syntenic group.

Complement Factor D in Age-Related Macular Degeneration

PubMed Central

Stanton, Chloe M.; Yates, John R.W.; den Hollander, Anneke I.; Seddon, Johanna M.; Swaroop, Anand; Stambolian, Dwight; Fauser, Sascha; Hoyng, Carel; Yu, Yi; Atsuhiro, Kanda; Branham, Kari; Othman, Mohammad; Chen, Wei; Kortvely, Elod; Chalmers, Kevin; Hayward, Caroline; Moore, Anthony T.; Dhillon, Baljean; Ueffing, Marius

2011-01-01

Purpose. To examine the role of complement factor D (CFD) in age-related macular degeneration (AMD) by analysis of genetic association, copy number variation, and plasma CFD concentrations. Methods. Single nucleotide polymorphisms (SNPs) in the CFD gene were genotyped and the results analyzed by binary logistic regression. CFD gene copy number was analyzed by gene copy number assay. Plasma CFD was measured by an enzyme-linked immunosorbent assay. Results. Genetic association was found between CFD gene SNP rs3826945 and AMD (odds ratio 1.44; P = 0.028) in a small discovery case-control series (462 cases and 325 controls) and replicated in a combined cohorts meta-analysis of 4765 cases and 2693 controls, with an odds ratio of 1.11 (P = 0.032), with the association almost confined to females. Copy number variation in the CFD gene was identified in 13 out of 640 samples examined but there was no difference in frequency between AMD cases (1.3%) and controls (2.7%). Plasma CFD concentration was measured in 751 AMD cases and 474 controls and found to be elevated in AMD cases (P = 0.00025). The odds ratio for those in the highest versus lowest quartile for plasma CFD was 1.81. The difference in plasma CFD was again almost confined to females. Conclusions. CFD regulates activation of the alternative complement pathway, which is implicated in AMD pathogenesis. The authors found evidence for genetic association between a CFD gene SNP and AMD and a significant increase in plasma CFD concentration in AMD cases compared with controls, consistent with a role for CFD in AMD pathogenesis. PMID:22003108

Spectrum of sequence variations in the FANCA gene: an International Fanconi Anemia Registry (IFAR) study.

PubMed

Levran, Orna; Diotti, Raffaella; Pujara, Kanan; Batish, Sat D; Hanenberg, Helmut; Auerbach, Arleen D

2005-02-01

Fanconi anemia (FA) is an autosomal recessive disorder that is defined by cellular hypersensitivity to DNA cross-linking agents, and is characterized clinically by developmental abnormalities, progressive bone-marrow failure, and predisposition to leukemia and solid tumors. There is extensive genetic heterogeneity, with at least 11 different FA complementation groups. FA-A is the most common group, accounting for approximately 65% of all affected individuals. The mutation spectrum of the FANCA gene, located on chromosome 16q24.3, is highly heterogeneous. Here we summarize all sequence variations (mutations and polymorphisms) in FANCA described in the literature and listed in the Fanconi Anemia Mutation Database as of March 2004, and report 61 novel FANCA mutations identified in FA patients registered in the International Fanconi Anemia Registry (IFAR). Thirty-eight novel SNPs, previously unreported in the literature or in dbSNP, were also identified. We studied the segregation of common FANCA SNPs in FA families to generate haplotypes. We found that FANCA SNP data are highly useful for carrier testing, prenatal diagnosis, and preimplantation genetic diagnosis, particularly when the disease-causing mutations are unknown. Twenty-two large genomic deletions were identified by detection of apparent homozygosity for rare SNPs. In addition, a conserved SNP haplotype block spanning at least 60 kb of the FANCA gene was identified in individuals from various ethnic groups. (c) 2005 Wiley-Liss, Inc.

The Sg-1 Glycosyltransferase Locus Regulates Structural Diversity of Triterpenoid Saponins of Soybean[W][OA

PubMed Central

Sayama, Takashi; Ono, Eiichiro; Takagi, Kyoko; Takada, Yoshitake; Horikawa, Manabu; Nakamoto, Yumi; Hirose, Aya; Sasama, Hiroko; Ohashi, Mihoko; Hasegawa, Hisakazu; Terakawa, Teruhiko; Kikuchi, Akio; Kato, Shin; Tatsuzaki, Nana; Tsukamoto, Chigen; Ishimoto, Masao

2012-01-01

Triterpene saponins are a diverse group of biologically functional products in plants. Saponins usually are glycosylated, which gives rise to a wide diversity of structures and functions. In the group A saponins of soybean (Glycine max), differences in the terminal sugar species located on the C-22 sugar chain of an aglycone core, soyasapogenol A, were observed to be under genetic control. Further genetic analyses and mapping revealed that the structural diversity of glycosylation was determined by multiple alleles of a single locus, Sg-1, and led to identification of a UDP-sugar–dependent glycosyltransferase gene (Glyma07g38460). Although their sequences are highly similar and both glycosylate the nonacetylated saponin A0-αg, the Sg-1a allele encodes the xylosyltransferase UGT73F4, whereas Sg-1b encodes the glucosyltransferase UGT73F2. Homology models and site-directed mutagenesis analyses showed that Ser-138 in Sg-1a and Gly-138 in Sg-1b proteins are crucial residues for their respective sugar donor specificities. Transgenic complementation tests followed by recombinant enzyme assays in vitro demonstrated that sg-10 is a loss-of-function allele of Sg-1. Considering that the terminal sugar species in the group A saponins are responsible for the strong bitterness and astringent aftertastes of soybean seeds, our findings herein provide useful tools to improve commercial properties of soybean products. PMID:22611180

A Viral Receptor Complementation Strategy to Overcome CAV-2 Tropism for Efficient Retrograde Targeting of Neurons.

PubMed

Li, Shu-Jing; Vaughan, Alexander; Sturgill, James Fitzhugh; Kepecs, Adam

2018-06-06

Retrogradely transported neurotropic viruses enable genetic access to neurons based on their long-range projections and have become indispensable tools for linking neural connectivity with function. A major limitation of viral techniques is that they rely on cell-type-specific molecules for uptake and transport. Consequently, viruses fail to infect variable subsets of neurons depending on the complement of surface receptors expressed (viral tropism). We report a receptor complementation strategy to overcome this by potentiating neurons for the infection of the virus of interest-in this case, canine adenovirus type-2 (CAV-2). We designed AAV vectors for expressing the coxsackievirus and adenovirus receptor (CAR) throughout candidate projection neurons. CAR expression greatly increased retrograde-labeling rates, which we demonstrate for several long-range projections, including some resistant to other retrograde-labeling techniques. Our results demonstrate a receptor complementation strategy to abrogate endogenous viral tropism and thereby facilitate efficient retrograde targeting for functional analysis of neural circuits. Copyright © 2018 Elsevier Inc. All rights reserved.

Allelic Variants of Complement Genes Associated with Dense Deposit Disease

PubMed Central

Abrera-Abeleda, Maria Asuncion; Nishimura, Carla; Frees, Kathy; Jones, Michael; Maga, Tara; Katz, Louis M.; Zhang, Yuzhou

2011-01-01

The alternative pathway of the complement cascade plays a role in the pathogenesis of dense deposit disease (DDD). Deficiency of complement factor H and mutations in CFH associate with the development of DDD, but it is unknown whether allelic variants in other complement genes also associate with this disease. We studied patients with DDD and identified previously unreported sequence alterations in several genes in addition to allelic variants and haplotypes common to patients with DDD. We found that the likelihood of developing DDD increases with the presence of two or more risk alleles in CFH and C3. To determine the functional consequence of this finding, we measured the activity of the alternative pathway in serum samples from phenotypically normal controls genotyped for variants in CFH and C3. Alternative pathway activity was higher in the presence of variants associated with DDD. Taken together, these data confirm that DDD is a complex genetic disease and may provide targets for the development of disease-specific therapies. PMID:21784901

A Genetic Screen for Mutants with Supersized Lipid Droplets in Caenorhabditis elegans

PubMed Central

Li, Shiwei; Xu, Shibin; Ma, Yanli; Wu, Shuang; Feng, Yu; Cui, Qingpo; Chen, Lifeng; Zhou, Shuang; Kong, Yuanyuan; Zhang, Xiaoyu; Yu, Jialei; Wu, Mengdi; Zhang, Shaobing O.

2016-01-01

To identify genes that regulate the dynamics of lipid droplet (LD) size, we have used the genetically tractable model organism Caenorhabditis elegans, whose wild-type LD population displays a steady state of size with an upper limit of 3 μm in diameter. From a saturated forward genetic screen of 6.7 × 105 mutagenized haploid genomes, we isolated 118 mutants with supersized intestinal LDs often reaching 10 μm. These mutants define nine novel complementation groups, in addition to four known genes (maoc-1, dhs-28, daf-22, and prx-10). The nine groups are named drop (lipid droplet abnormal) and categorized into four classes. Class I mutants drop-5 and drop-9, similar to prx-10, are up-regulated in ACS-22-DGAT-2-dependent LD growth, resistant to LD hydrolysis, and defective in peroxisome import. Class II mutants drop-2, drop-3, drop-6, and drop-7 are up-regulated in LD growth, are resistant to LD hydrolysis, but are not defective in peroxisome import. Class III mutants drop-1 and drop-8 are neither up-regulated in LD growth nor resistant to LD hydrolysis, but seemingly up-regulated in LD fusion. Class IV mutant drop-4 is cloned as sams-1 and, different to the other three classes, is ACS-22-independent and hydrolysis-resistant. These four classes of supersized LD mutants should be valuable for mechanistic studies of LD cellular processes including growth, hydrolysis, and fusion. PMID:27261001

The Symbiotic Relationship of Science and Technology in the 21st Century.

ERIC Educational Resources Information Center

Wiens, A. Emerson

1999-01-01

There are many examples in which science and technology complement each other. This is especially evident in biotechnology and genetic engineering. This symbiotic relationship is foundational to the technological culture of contemporary society. (SK)

Genetics Home Reference: complement component 2 deficiency

MedlinePlus

... deficiency Sources for This Page Jönsson G, Sjöholm AG, Truedsson L, Bengtsson AA, Braconier JH, Sturfelt G. ... L, Sturfelt G, Oxelius VA, Braconier JH, Sjöholm AG. Hereditary C2 deficiency in Sweden: frequent occurrence of ...

The contribution of an animal model toward uncovering biological risk factors for PTSD.

PubMed

Cohen, Hagit; Matar, Michael A; Richter-Levin, Gal; Zohar, Joseph

2006-07-01

Clinical studies of posttraumatic stress disorder (PTSD) have elicited proposed risk factors for developing PTSD in the aftermath of stress exposure. Generally, these risk factors have arisen from retrospective analysis of premorbid characteristics of study populations. A valid animal model of PTSD can complement clinical studies and help to elucidate issues, such as the contribution of proposed risk factors, in ways which are not practicable in the clinical arena. Important qualities of animal models include the possibility to conduct controlled prospective studies, easy access to postmortem brains, and the availability of genetically manipulated subjects, which can be tailored to specific needs. When these qualities are further complemented by an approach which defines phenomenologic criteria to address the variance in individual response pattern and magnitude, enabling the animal subjects to be classified into definable groups for focused study, the model acquires added validity. This article presents an overview of a series of studies in such an animal model which examine the contribution of two proposed risk factors and the value of two early postexposure pharmacological manipulations on the prevalence rates of subjects displaying an extreme magnitude of behavioral response to a predator stress paradigm.

Environmental adjuvants, apoptosis and the censorship over autoimmunity.

PubMed

Rovere-Querini, Patrizia; Manfredi, Angelo A; Sabbadini, Maria Grazia

2005-11-01

Alterations during apoptosis lead to the activation of autoreactive T cells and the production of autoantibodies. This article discusses the pathogenic potential of cells dying in vivo, dissecting the role of signals that favor immune responses (adjuvants) and the influence of genetic backgrounds. Diverse factors determine whether apoptosis leads or not to a self-sustaining, clinically apparent autoimmune disease. The in vivo accumulation of uncleared dying cells per se is not sufficient to cause disease. However, dying cells are antigenic and their complementation with immune adjuvants causes lethal diseases in predisposed lupus-prone animals. At least some adjuvant signals directly target the function and the activation state of antigen presenting cells. Several laboratories are aggressively pursuing the molecular identification of endogenous adjuvants. Sodium monourate and the high mobility group B1 protein (HMGB1) are, among those identified so far, well known to rheumatologists. However, even the complementation of apoptotic cells with potent adjuvant signals fail to cause clinical autoimmunity in most strains: autoantibodies generated are transient, do not undergo to epitope/spreading and do not cause disease. Novel tools for drug development will derive from the molecular identification of the constraints that prevent autoimmunity in normal subjects.

Effects of partial replacement of fish meal by yeast hydrolysate on complement system and stress resistance in juvenile Jian carp (Cyprinus carpio var. Jian).

PubMed

Yuan, Xiang-Yang; Liu, Wen-Bin; Liang, Chao; Sun, Cun-Xin; Xue, Yun-Fei; Wan, Zu-De; Jiang, Guang-Zhen

2017-08-01

A 10-week feeding trial was carried out to investigate the effects of dietary fish meal replacement by yeast hydrolysate (YH) on growth performance, complement system and stress resistance of juvenile Jian carp (Cyprinus carpio var. Jian) (initial average weight 19.44 ± 0.06 g). In the study, there were five groups: one control group was fed with a basal diet (YH0), and four treatment groups were fed with dietary fish meal replaced by 1% YH (YH1), 3% (YH3), 5% (YH5) and 7% (YH7), respectively. Each group had four replicates. At the end of feeding trial, twelve fish from each group (three fish per replicate) were randomly selected for assessing the growth and immunity. Meanwhile, 20 fish per replicate were injected by Aeromonas hydrophila. The results showed that (1) Replacement levels of YH significantly affected the growth of the fish with the highest values of weight gain (WG) occurred in fish fed YH3 diet. However, no significant difference in feed conversion ratios (FCR) was observed among all groups. (2) Pre-stressed plasma lysozyme activity, total protein and albumin contents and complement component 3 (C3) and complement component 4 (C4) levels of fish fed YH3 diet were significantly higher than those of fish fed YH0 diet. However, post-stressed immune parameters of fish in all groups were significantly lower. (3) There was a trend that the expression levels of the complement-related genes (c1r/s-A, c4-1, c3-H1, c5-1, fb/c2-A, mbl-2 and masp) initially increased and then decreased except mbl-2 and masp, with the maximum values observed in fish fed YH3 diet. Before stress, the expression levels of the inflammation-related genes (alp, il-1β and tnf-α) in the hepatopancreas and spleen of fish fed YH1 diet and YH7 diet were significant higher than that of fish fed YH0 diet. After stress, no significant difference in the expression levels of those genes was observed among all groups. These results indicated that FM replacement by YH could improve growth performance, enhance innate immunity, and activate complement via the alternative complement pathway (ACP) and the classical complement pathway (CCP). Copyright © 2017 Elsevier Ltd. All rights reserved.

Language and False-Belief Task Performance in Children With Autism Spectrum Disorder.

PubMed

Jeffrey Farrar, M; Seung, Hye Kyeung; Lee, Hyeonjin

2017-07-12

Language is related to false-belief (FB) understanding in both typically developing children and children with autism spectrum disorder (ASD). The current study examined the role of complementation and general language in FB understanding. Of interest was whether language plays similar or different roles in the groups' FB performance. Participants were 16 typically developing children (mean age = 5.0 years; mental age = 6.7) and 18 with ASD (mean age = 7.3 years; mental age = 8.3). Children were administered FB and language tasks (say- and think-complements), receptive and expressive vocabulary tests, and relative clauses. When mental age and receptive and expressive vocabulary were used as separate covariates, the typical control group outperformed the children with ASD in FB task performance. Chi-square analyses indicated that passing both complementation tasks was linked to the FB understanding of children with ASD. Children with ASD who passed FB tasks all passed say- and think-complement tasks. However, some children in the control group were able to pass the FB tasks, even if they failed the say- and think-complement tasks. The results indicate that children with ASD relied more on complement understanding to pass FB than typically developing children. Results are discussed regarding the developmental pathways for FB understanding.

The XX sex chromosome complement in mice is associated with increased spontaneous lupus compared with XY.

PubMed

Sasidhar, Manda V; Itoh, Noriko; Gold, Stefan M; Lawson, Gregory W; Voskuhl, Rhonda R

2012-08-01

Many autoimmune diseases are characterised by a female predominance. This may be caused by sex hormones, sex chromosomes or both. This report uses a transgenic mouse model to investigate how sex chromosome complement, not confounded by differences in gonadal type, might contribute to lupus pathogenesis. Transgenic NZM2328 mice were created by deletion of the Sry gene from the Y chromosome, thereby separating genetic from gonadal sex. Survival, renal histopathology and markers of immune activation were compared in mice carrying the XX versus the XY(-) sex chromosome complement, with each genotype being ovary bearing. Mice with XX sex chromosome complement compared with XY(-) exhibited poorer survival rates and increased kidney pathology. Splenic T lymphocytes from XX mice demonstrated upregulated X-linked CD40 ligand expression and higher levels of activation markers ex vivo. Increased MMP, TGF and IL-13 production was found, while IL-2 was lower in XX mice. An accumulation of splenic follicular B cells and peritoneal marginal zone B cells was observed, coupled with upregulated costimulatory marker expression on B cells in XX mice. These data show that the XX sex chromosome complement, compared with XY(-), is associated with accelerated spontaneous lupus.

Evidence for a repair enzyme complex involving ERCC1 and complementing activities of ERCC4, ERCC11 and xeroderma pigmentosum group F.

PubMed Central

van Vuuren, A J; Appeldoorn, E; Odijk, H; Yasui, A; Jaspers, N G; Bootsma, D; Hoeijmakers, J H

1993-01-01

Nucleotide excision repair (NER), one of the major cellular DNA repair systems, removes a wide range of lesions in a multi-enzyme reaction. In man, a NER defect due to a mutation in one of at least 11 distinct genes, can give rise to the inherited repair disorders xeroderma pigmentosum (XP), Cockayne's syndrome or PIBIDS, a photosensitive form of the brittle hair disease trichothiodystrophy. Laboratory-induced NER-deficient mutants of cultured rodent cells have been classified into 11 complementation groups (CGs). Some of these have been shown to correspond with human disorders. In cell-free extracts prepared from rodent CGs 1-5 and 11, but not in a mutant from CG6, we find an impaired repair of damage induced in plasmids by UV light and N-acetoxy-acetylaminofluorene. Complementation analysis in vitro of rodent CGs is accomplished by pairwise mixing of mutant extracts. The results show that mutants from groups 2, 3, 5 and XP-A can complement all other CGs tested. However, selective non-complementation in vitro was observed in mutual mixtures of groups 1, 4, 11 and XP-F, suggesting that the complementing activities involved somehow affect each other. Depletion of wild-type human extracts from ERCC1 protein using specific anti-ERCC1 antibodies concomitantly removed the correcting activities for groups 4, 11 and XP-F, but not those for the other CGs. Furthermore, we find that 33 kDa ERCC1 protein sediments as a high mol. wt species of approximately 120 kDa in a native glycerol gradient.(ABSTRACT TRUNCATED AT 250 WORDS) Images PMID:8253091

Mining drug-disease relationships as a complement to medical genetics-based drug repositioning: Where a recommendation system meets genome-wide association studies.

PubMed

Wang, H; Gu, Q; Wei, J; Cao, Z; Liu, Q

2015-05-01

A novel recommendation-based drug repositioning strategy is presented to simultaneously determine novel drug indications and side effects in one integrated framework. This strategy provides a complementary method to medical genetics-based drug repositioning, which reduces the occurrence of false positives in medical genetics-based drug repositioning, resulting in a ranked list of new candidate indications and/or side effects with different confidence levels. Several new drug indications and side effects are reported with high prediction confidences. © 2015 American Society for Clinical Pharmacology and Therapeutics.

Genetic Complementation of the Obligate Marine Actinobacterium Salinispora tropica with the Large Mechanosensitive Channel Gene mscL Rescues Cells from Osmotic Downshock

PubMed Central

Bucarey, Sergio A.; Penn, Kevin; Paul, Lauren; Fenical, William

2012-01-01

Marine actinomycetes in the genus Salinispora fail to grow when seawater is replaced with deionized (DI) water in complex growth media. While bioinformatic analyses have led to the identification of a number of candidate marine adaptation genes, there is currently no experimental evidence to support the genetic basis for the osmotic requirements associated with this taxon. One hypothesis is that the lineage-specific loss of mscL is responsible for the failure of strains to grow in media prepared with DI water. The mscL gene encodes a conserved transmembrane protein that reduces turgor pressure under conditions of acute osmotic downshock. In the present study, the mscL gene from a Micromonospora strain capable of growth on media prepared with DI water was transformed into S. tropica strain CNB-440. The single-copy, chromosomal genetic complementation yielded a recombinant Salinispora mscL+ strain that demonstrated an increased capacity to survive osmotic downshock. The enhanced survival of the S. tropica transformant provides experimental evidence that the loss of mscL is associated with the failure of Salinispora spp. to grow in low-osmotic-strength media. PMID:22492446

Role of Complement Activation in a Model of Adult Respiratory Distress Syndrome

PubMed Central

Hosea, Stephen; Brown, Eric; Hammer, Carl; Frank, Michael

1980-01-01

The adult respiratory distress syndrome is characterized by arterial hypoxemia as a result of increased alveolar capillary permeability to serum proteins in the setting of normal capillary hydrostatic pressures. Because bacterial sepsis is prominent among the various diverse conditions associated with altered alveolar capillary permeability, we studied the effect of bacteremia with attendant complement activation on the sequestration of microorganisms and the leakage of albumin in the lungs of guinea pigs. Pneumococci were injected intravenously into guinea pigs and their localization was studied. Unlike normal guinea pigs, complement-depleted guinea pigs did not localize injected bacteria to the lungs. Preopsonization of organisms did not correct this defect in pulmonary localization of bacteria in complement-depleted animals, suggesting that a fluid-phase component of complement activation was required. Genetically C5-deficient mice showed no pulmonary localization of bacteria. C5-sufficient mice demonstrated the usual pulmonary localization, thus further suggesting that the activation of C5 might be important in this localization. The infusion of activated C5 increased alveolar capillary permeability to serum proteins as assayed by the amount of radioactive albumin sequestered in the lung. Neutropenic animals did not develop altered capillary permeability after challenge with activated C5. Thus, complement activation through C5, in the presence of neutrophils, induces alterations in pulmonary alveolar capillary permeability and causes localization of bacteria to the pulmonary parenchyma. Complement activation in other disease states could potentially result in similar clinical manifestations. PMID:7400321

A targeted complement-dependent strategy to improve the outcome of mAb therapy, and characterization in a murine model of metastatic cancer

PubMed Central

Elvington, Michelle; Huang, Yuxiang; Morgan, B. Paul; Qiao, Fei; van Rooijen, Nico; Atkinson, Carl

2012-01-01

Complement inhibitors expressed on tumor cells provide an evasion mechanism against mAb therapy and may modulate the development of an acquired antitumor immune response. Here we investigate a strategy to amplify mAb-targeted complement activation on a tumor cell, independent of a requirement to target and block complement inhibitor expression or function, which is difficult to achieve in vivo. We constructed a murine fusion protein, CR2Fc, and demonstrated that the protein targets to C3 activation products deposited on a tumor cell by a specific mAb, and amplifies mAb-dependent complement activation and tumor cell lysis in vitro. In syngeneic models of metastatic lymphoma (EL4) and melanoma (B16), CR2Fc significantly enhanced the outcome of mAb therapy. Subsequent studies using the EL4 model with various genetically modified mice and macrophage-depleted mice revealed that CR2Fc enhanced the therapeutic effect of mAb therapy via both macrophage-dependent FcγR-mediated antibody-dependent cellular cytotoxicity, and by direct complement-mediated lysis. Complement activation products can also modulate adaptive immunity, but we found no evidence that either mAb or CR2Fc treatment had any effect on an antitumor humoral or cellular immune response. CR2Fc represents a potential adjuvant treatment to increase the effectiveness of mAb therapy of cancer. PMID:22442351

Rituximab fails where eculizumab restores renal function in C3nef-related DDD.

PubMed

Rousset-Rouvière, Caroline; Cailliez, Mathilde; Garaix, Florentine; Bruno, Daniele; Laurent, Daniel; Tsimaratos, Michel

2014-06-01

Dense deposit disease (DDD), a C3 glomerulopathy (C3G), is a rare disease with unfavorable progression towards end-stage kidney disease. The pathogenesis of DDD is due to cytotoxic effects related to acquired or genetic dysregulation of the complement alternative pathway, which is at times accompanied by the production of C3 nephritic factor (C3NeF), an auto-antibody directed against the alternative C3 convertase. Available treatments include plasma exchange, CD20-targeted antibodies, and a terminal complement blockade via the anti-C5 monoclonal antibody eculizumab. We report here the case of an 8-year-old child with C3NeF and refractory DDD who presented with a nephritic syndrome. She tested positive for C3NeF activity; C3 was undetectable. Genetic analyses of the alternative complement pathway were normal. Methylprednisolone pulses and mycophenolate mofetil treatment resulted in complete recovery of renal function and a reduction in proteinuria. Corticosteroids were tapered and then withdrawn. Four months after corticosteroid discontinuation, hematuria and proteinuria recurred, and a renal biopsy confirmed an active DDD with a majority of extracapillary crescents. Despite an increase in immunosuppressive drugs, including methylprednisolone pulses and rituximab therapy, the patient suffered acute renal failure within 3 weeks, requiring dialysis. Eculizumab treatment resulted in a quick and impressive response. Hematuria very quickly resolved, kidney function improved, and no further dialysis was required. The patient received bimonthly eculizumab injections of 600 mg, allowing for normalization of renal function and reduction of proteinuria to <0.5 g per day. Since then, she continues to receive eculizumab. Complement regulation pathway-targeted therapy may be a specific and useful treatment for rapidly progressing DDD prior to the development of glomerulosclerosis. Our data provide evidence supporting the pivotal role of complement alternative pathway abnormalities in C3G with DDD.

Genome-Wide Variation Patterns Uncover the Origin and Selection in Cultivated Ginseng (Panax ginseng Meyer)

PubMed Central

Li, Ming-Rui; Shi, Feng-Xue; Li, Ya-Ling; Jiang, Peng; Jiao, Lili

2017-01-01

Abstract Chinese ginseng (Panax ginseng Meyer) is a medicinally important herb and plays crucial roles in traditional Chinese medicine. Pharmacological analyses identified diverse bioactive components from Chinese ginseng. However, basic biological attributes including domestication and selection of the ginseng plant remain under-investigated. Here, we presented a genome-wide view of the domestication and selection of cultivated ginseng based on the whole genome data. A total of 8,660 protein-coding genes were selected for genome-wide scanning of the 30 wild and cultivated ginseng accessions. In complement, the 45s rDNA, chloroplast and mitochondrial genomes were included to perform phylogenetic and population genetic analyses. The observed spatial genetic structure between northern cultivated ginseng (NCG) and southern cultivated ginseng (SCG) accessions suggested multiple independent origins of cultivated ginseng. Genome-wide scanning further demonstrated that NCG and SCG have undergone distinct selection pressures during the domestication process, with more genes identified in the NCG (97 genes) than in the SCG group (5 genes). Functional analyses revealed that these genes are involved in diverse pathways, including DNA methylation, lignin biosynthesis, and cell differentiation. These findings suggested that the SCG and NCG groups have distinct demographic histories. Candidate genes identified are useful for future molecular breeding of cultivated ginseng. PMID:28922794

Chromosomal localization of three repair genes: The xeroderma pigmentosum group C gene and two human homologs of yeast RAD23

DOE Office of Scientific and Technical Information (OSTI.GOV)

Spek, P.J. van der; Smit, E.M.E.; Beverloo, H.B.

1994-10-01

The nucleotide excision repair (NER) disorder xeroderma pigmentosum (XP) is characterized by sun (UV) sensitivity, predisposition to skin cancer, and extensive genetic heterogeneity. Recently, we reported the cloning and analysis of three human NER genes, XPC, HHR23A, and HHR23B. The previously cloned XPC gene is involved in the common XP complementation group C, which is defective in excision repair of nontranscribed sequences in the genome. The XPC protein was found to be complexed with the product of HHR23B, one of the two human homologs of the Saccharomyes cerevisiae NER gene RAD23. Here we present the chromosomal localization by in situmore » hybridization using haptenized probes of all three genes. The HHR23A gene was assigned to chromosome 19p13.2. Interestingly, the HHR23B and XPC genes, the product of which forms a tight complex, were found to colocalize on band 3p25.1. Pulsed-field gel electrophoresis revealed that the HHR23B and XPC genes possibly share a MluI restriction fragment of about 625 kb. Potential involvement of the HHR23 genes in human genetic disorders is discussed. 53 refs., 4 figs., 2 tabs.« less

Comparison of the effectiveness of ISJ and SSR markers and detection of outlier loci in conservation genetics of Pulsatilla patens populations

PubMed Central

Szczecińska, Monika

2016-01-01

Background Research into the protection of rare and endangered plant species involves genetic analyses to determine their genetic variation and genetic structure. Various categories of genetic markers are used for this purpose. Microsatellites, also known as simple sequence repeats (SSR), are the most popular category of markers in population genetics research. In most cases, microsatellites account for a large part of the noncoding DNA and exert a neutral effect on the genome. Neutrality is a desirable feature in evaluations of genetic differences between populations, but it does not support analyses of a population’s ability to adapt to a given environment or its evolutionary potential. Despite the numerous advantages of microsatellites, non-neutral markers may supply important information in conservation genetics research. They are used to evaluate adaptation to specific environmental conditions and a population’s adaptive potential. The aim of this study was to compare the level of genetic variation in Pulsatilla patens populations revealed by neutral SSR markers and putatively adaptive ISJ markers (intron-exon splice junction). Methods The experiment was conducted on 14 Polish populations of P. patens and three P. patens populations from the nearby region of Vitebsk in Belarus. A total of 345 individuals were examined. Analyses were performed with the use of eight SSR primers specific to P. patens and three ISJ primers. Results SSR markers revealed a higher level of genetic variation than ISJ markers (He = 0.609, He = 0.145, respectively). An analysis of molecular variance (AMOVA) revealed that, the overall genetic diversity between the analyzed populations defined by parameters FST and ΦPT for SSR (20%) and ΦPT for ISJ (21%) markers was similar. Analysis conducted in the Structure program divided analyzed populations into two groups (SSR loci) and three groups (ISJ markers). Mantel test revealed correlations between the geographic distance and genetic diversity of Polish populations of P. patens for ISJ markers, but not for SSR markers. Conclusions The results of the present study suggest that ISJ markers can complement the analyses based on SSRs. However, neutral and adaptive markers should not be alternatively applied. Neutral microsatellite markers cannot depict the full range of genetic variation in a population because they do not enable to analyze functional variation. Although ISJ markers are less polymorphic, they can contribute to the reliability of analyses based on SSRs. PMID:27833793

Current issues in medically assisted reproduction and genetics in Europe: research, clinical practice, ethics, legal issues and policy. European Society of Human Genetics and European Society of Human Reproduction and Embryology.

PubMed

Harper, Joyce C; Geraedts, Joep; Borry, Pascal; Cornel, Martina C; Dondorp, Wybo; Gianaroli, Luca; Harton, Gary; Milachich, Tanya; Kääriäinen, Helena; Liebaers, Inge; Morris, Michael; Sequeiros, Jorge; Sermon, Karen; Shenfield, Françoise; Skirton, Heather; Soini, Sirpa; Spits, Claudia; Veiga, Anna; Vermeesch, Joris Robert; Viville, Stéphane; de Wert, Guido; Macek, Milan

2013-11-01

In March 2005, a group of experts from the European Society of Human Genetics and European Society of Human Reproduction and Embryology met to discuss the interface between genetics and assisted reproductive technology (ART), and published an extended background paper, recommendations and two Editorials. Seven years later, in March 2012, a follow-up interdisciplinary workshop was held, involving representatives of both professional societies, including experts from the European Union Eurogentest2 Coordination Action Project. The main goal of this meeting was to discuss developments at the interface between clinical genetics and ARTs. As more genetic causes of reproductive failure are now recognised and an increasing number of patients undergo testing of their genome before conception, either in regular health care or in the context of direct-to-consumer testing, the need for genetic counselling and preimplantation genetic diagnosis (PGD) may increase. Preimplantation genetic screening (PGS) thus far does not have evidence from randomised clinical trials to substantiate that the technique is both effective and efficient. Whole-genome sequencing may create greater challenges both in the technological and interpretational domains, and requires further reflection about the ethics of genetic testing in ART and PGD/PGS. Diagnostic laboratories should be reporting their results according to internationally accepted accreditation standards (International Standards Organisation - ISO 15189). Further studies are needed in order to address issues related to the impact of ART on epigenetic reprogramming of the early embryo. The legal landscape regarding assisted reproduction is evolving but still remains very heterogeneous and often contradictory. The lack of legal harmonisation and uneven access to infertility treatment and PGD/PGS fosters considerable cross-border reproductive care in Europe and beyond. The aim of this paper is to complement previous publications and provide an update of selected topics that have evolved since 2005.

Complement Factor B Mutations in Atypical Hemolytic Uremic Syndrome—Disease-Relevant or Benign?

PubMed Central

Marinozzi, Maria Chiara; Vergoz, Laura; Rybkine, Tania; Ngo, Stephanie; Bettoni, Serena; Pashov, Anastas; Cayla, Mathieu; Tabarin, Fanny; Jablonski, Mathieu; Hue, Christophe; Smith, Richard J.; Noris, Marina; Halbwachs-Mecarelli, Lise; Donadelli, Roberta; Fremeaux-Bacchi, Veronique

2014-01-01

Atypical hemolytic uremic syndrome (aHUS) is a genetic ultrarare renal disease associated with overactivation of the alternative pathway of complement. Four gain-of-function mutations that form a hyperactive or deregulated C3 convertase have been identified in Factor B (FB) ligand binding sites. Here, we studied the functional consequences of 10 FB genetic changes recently identified from different aHUS cohorts. Using several tests for alternative C3 and C5 convertase formation and regulation, we identified two gain-of-function and potentially disease-relevant mutations that formed either an overactive convertase (M433I) or a convertase resistant to decay by FH (K298Q). One mutation (R178Q) produced a partially cleaved protein with no ligand binding or functional activity. Seven genetic changes led to near-normal or only slightly reduced ligand binding and functional activity compared with the most common polymorphism at position 7, R7. Notably, none of the algorithms used to predict the disease relevance of FB mutations agreed completely with the experimental data, suggesting that in silico approaches should be undertaken with caution. These data, combined with previously published results, suggest that 9 of 15 FB genetic changes identified in patients with aHUS are unrelated to disease pathogenesis. This study highlights that functional assessment of identified nucleotide changes in FB is mandatory to confirm disease association. PMID:24652797

Fanconi anemia with biallelic FANCD1/BRCA2 mutations - Case report of a family with three affected children.

PubMed

Svojgr, Karel; Sumerauer, David; Puchmajerova, Alena; Vicha, Ales; Hrusak, Ondrej; Michalova, Kyra; Malis, Josef; Smisek, Petr; Kyncl, Martin; Novotna, Drahuse; Machackova, Eva; Jencik, Jan; Pycha, Karel; Vaculik, Miroslav; Kodet, Roman; Stary, Jan

2016-03-01

Fanconi anemia, complementation group D1 with bi-allelic FANCD1 (BRCA2) mutations, is a very rare genetic disorder characterized by early onset of childhood malignancies, including acute leukemia, brain cancer and nephroblastoma. Here, we present a case report of a family with 3 affected children in terms of treatment outcome, toxicity and characterization of the malignancies using comprehensive cytogenetic analysis. The first child was diagnosed with T-cell acute lymphoblastic leukemia when he was 11 months old. During chemotherapy, he suffered from repeated pancytopenia, sepsis and severe vincristine polyneuropathy, and 18 months after primary diagnosis, he succumbed to secondary acute monocytic leukemia. The second child was diagnosed with stage 2 triphasic nephroblastoma (Wilms tumor), when he was 3 years and 11 months old. During chemotherapy, he suffered from vincristine polyneuropathy. Currently, he is in complete remission, 29 months following the initial diagnosis. The third child was diagnosed with medulloblastoma with classical histology, when she was 4 years and 5 months old. After the first cycle of chemotherapy, she suffered from prolonged pancytopenia, sepsis and severe skin and mucosal toxicity. Six weeks after primary diagnosis, a first relapse in the posterior fossa was diagnosed, and at 7 and half months after primary diagnosis, a second relapse was diagnosed that led to the patient's death. Our case report underscores tumor heterogeneity, treatment toxicity and poor outcome in Fanconi anemia patients of complementation group D1. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Molecular Genetic Analysis of an Endotoxin Nonresponder Mutant Cell Line

PubMed Central

Schromm, Andra B.; Lien, Egil; Henneke, Philipp; Chow, Jesse C.; Yoshimura, Atsutoshi; Heine, Holger; Latz, Eicke; Monks, Brian G.; Schwartz, David A.; Miyake, Kensuke; Golenbock, Douglas T.

2001-01-01

Somatic cell mutagenesis is a powerful tool for characterizing receptor systems. We reported previously two complementation groups of mutant cell lines derived from CD14-transfected Chinese hamster ovary–K1 fibroblasts defective in responses to bacterial endotoxin. Both classes of mutants expressed a normal gene product for Toll-like receptor (TLR)4, and fully responded to stimulation by tumor necrosis factor (TNF)-α or interleukin (IL)-1β. We identified the lesion in one of the complementation groups in the gene for MD-2, a putative TLR4 coreceptor. The nonresponder phenotype of this mutant was reversed by transfection with MD-2. Cloning of MD-2 from the nonresponder cell line revealed a point mutation in a highly conserved region resulting in a C95Y amino acid exchange. Both forms of MD-2 colocalized with TLR4 on the cell surface after transfection, but only the wild-type cDNA reverted the lipopolysaccharide (LPS) nonresponder phenotype. Furthermore, soluble MD-2, but not soluble MD-2C95Y, functioned to enable LPS responses in cells that expressed TLR4. Thus, MD-2 is a required component of the LPS signaling complex and can function as a soluble receptor for cells that do not otherwise express it. We hypothesize that MD-2 conformationally affects the extracellular domain of TLR4, perhaps resulting in a change in affinity for LPS or functioning as a portion of the true ligand for TLR4. PMID:11435474

Preservation of renal function in atypical hemolytic uremic syndrome by eculizumab: a case report.

PubMed

Giordano, Mario; Castellano, Giuseppe; Messina, Giovanni; Divella, Claretta; Bellantuono, Rosa; Puteo, Flora; Colella, Vincenzo; Depalo, Tommaso; Gesualdo, Loreto

2012-11-01

Genetic mutations in complement components are associated with the development of atypical hemolytic uremic syndrome (aHUS), a rare disease with high morbidity rate triggered by infections or unidentified factors. The uncontrolled activation of the alternative pathway of complement results in systemic endothelial damage leading to progressive development of renal failure. A previously healthy 8-month-old boy was referred to our hospital because of onset of fever, vomiting, and a single episode of nonbloody diarrhea. Acute kidney injury with preserved diuresis, hemolytic anemia, and thrombocytopenia were detected, and common protocols for management of HUS were followed without considerable improvement. The persistent low levels of complement component C3 led us to hypothesize the occurrence of aHUS. In fact, the child carried a specific mutation in complement factor H (Cfh; nonsense mutation in 3514G>T, serum levels of Cfh 138 mg/L, normal range 350-750). Given the lack of response to therapy and the occurrence of kidney failure requiring dialysis, we used eculizumab as rescue therapy, a monoclonal humanized antibody against the complement component C5. One week from the first administration, we observed a significant improvement of all clinical and laboratory parameters with complete recovery from hemodialysis, even in the presence of systemic infections. Our case report shows that complement inhibiting treatment allows the preservation of renal function and avoids disease relapses during systemic infections.

[Variations of peripheral blood autoantibody, immunoglobuliln, and complement levels in patients with non-lactational mastitis and their clinical significances].

PubMed

Xu, Rui; Guo, Qian-Qian; Yang, Le-Ping; Lai, Mi-Lin; Tong, Lin

2016-08-20

To detect the variations in peripheral blood levels of autoantibodies, immunoglobulilns and complements in patients with non-lactational mastitis and investigate whether non-lactational mastitis is an autoimmune disease with immune dysfunction. Seven-eight patients with non-lactational mastitis treated in our hospital between September 2013 and May 2015 and 88 healthy women (control) were examined for peripheral blood levels of antinuclear antibody (ANA), anti-histone antibody (AHA), immunoglobulins (IgA, IgM, and IgG) and complements (C3, C4, and total complements). s Of the 78 patients with non-lactational mastitis, 50 (64.10%) were positive of ANA showing mainly the granular and cytoplasmic granular fluorescence patterns, and the positivity rate was significantly higher than that in the control group (P<0.000). Twenty-eight (36.00%) of the patients were positive of AHA, a rate significantly higher than that in the control group (P<0.000). The levels of IgA, IgM, C4, and total complements levels were all significantly elevated in the patients compared with those in the control group (P<0.05). Patients with non-lactational mastitis have abnormal changes in peripheral blood levels of immunoglobulins and complements with high positivity rates for ANA and AHA, indicating that non-lactational mastitis is an autoimmune disease with immune dysfunction.

Alike but different: the evolution of the Tubifex tubifex species complex (Annelida, Clitellata) through polyploidization.

PubMed

Marotta, Roberto; Crottini, Angelica; Raimondi, Elena; Fondello, Cristina; Ferraguti, Marco

2014-04-02

Tubifex tubifex is a widespread annelid characterized by considerable variability in its taxonomic characteristics and by a mixed reproductive strategy, with both parthenogenesis and biparental reproduction. In a molecular phylogenetic analysis, we detected substantial genetic variability among sympatric Tubifex spp. from the Lambro River (Milano, Italy), which we suggested comprise several cryptic species. To gain insights into the evolutionary events that generated this differentiation, we performed a cytogenetic analysis in parallel with a molecular assay. Approximately 80 cocoons of T. tubifex and T. blanchardi were collected and dissected. For each cocoon, we sequenced a fragment of the 16S rRNA from half of the sibling embryos and karyotyped the other half. To generate a robust phylogeny enabling the reconstruction of the evolutionary processes shaping the diversity of these sympatric lineages, we complemented our original 16S rRNA gene sequences with additional COI sequences. The chromosome number distribution was consistent with the presence of at least six sympatric euploid chromosome complements (one diploid, one triploid, three tetraploids and one hexaploid), as confirmed by a FISH assay performed with an homologous 18S rDNA probe. All the worms with 2n = 50 chromosomes belonged to an already identified sibling species of T. tubifex, T. blanchardi. The six euploid sets were coherently arranged in the phylogeny, with each lineage grouping specimens with the same chromosome complement. These results are compatible with the hypothesis that multiple polyploidization events, possibly enhanced by parthenogenesis, may have driven the evolution of the T. tubifex species complex.

Genetic susceptibility to chronic wasting disease in free-ranging white-tailed deer: complement component C1q and Prnp polymorphisms

USGS Publications Warehouse

Blanchong, Julie A.; Heisey, Dennis M.; Scribner, Kim T.; Libants, Scot V.; Johnson, Chad; Aiken, Judd M.; Langenberg, Julia A.; Samuel, Michael D.

2009-01-01

The genetic basis of susceptibility to chronic wasting disease (CWD) in free-ranging cervids is of great interest. Association studies of disease susceptibility in free-ranging populations, however, face considerable challenges including: the need for large sample sizes when disease is rare, animals of unknown pedigree create a risk of spurious results due to population admixture, and the inability to control disease exposure or dose. We used an innovative matched case–control design and conditional logistic regression to evaluate associations between polymorphisms of complement C1q and prion protein (Prnp) genes and CWD infection in white-tailed deer from the CWD endemic area in south-central Wisconsin. To reduce problems due to admixture or disease-risk confounding, we used neutral genetic (microsatellite) data to identify closely related CWD-positive (n = 68) and CWD-negative (n = 91) female deer to serve as matched cases and controls. Cases and controls were also matched on factors (sex, location, age) previously demonstrated to affect CWD infection risk. For Prnp, deer with at least one Serine (S) at amino acid 96 were significantly less likely to be CWD-positive relative to deer homozygous for Glycine (G). This is the first characterization of genes associated with the complement system in white-tailed deer. No tests for association between any C1q polymorphism and CWD infection were significant at p < 0.05. After controlling for Prnp, we found weak support for an elevated risk of CWD infection in deer with at least one Glycine (G) at amino acid 56 of the C1qC gene. While we documented numerous amino acid polymorphisms in C1q genes none appear to be strongly associated with CWD susceptibility.

Independent evolution of neurotoxin and flagellar genetic loci in proteolytic Clostridium botulinum

PubMed Central

Carter, Andrew T; Paul, Catherine J; Mason, David R; Twine, Susan M; Alston, Mark J; Logan, Susan M; Austin, John W; Peck, Michael W

2009-01-01

Background Proteolytic Clostridium botulinum is the causative agent of botulism, a severe neuroparalytic illness. Given the severity of botulism, surprisingly little is known of the population structure, biology, phylogeny or evolution of C. botulinum. The recent determination of the genome sequence of C. botulinum has allowed comparative genomic indexing using a DNA microarray. Results Whole genome microarray analysis revealed that 63% of the coding sequences (CDSs) present in reference strain ATCC 3502 were common to all 61 widely-representative strains of proteolytic C. botulinum and the closely related C. sporogenes tested. This indicates a relatively stable genome. There was, however, evidence for recombination and genetic exchange, in particular within the neurotoxin gene and cluster (including transfer of neurotoxin genes to C. sporogenes), and the flagellar glycosylation island (FGI). These two loci appear to have evolved independently from each other, and from the remainder of the genetic complement. A number of strains were atypical; for example, while 10 out of 14 strains that formed type A1 toxin gave almost identical profiles in whole genome, neurotoxin cluster and FGI analyses, the other four strains showed divergent properties. Furthermore, a new neurotoxin sub-type (A5) has been discovered in strains from heroin-associated wound botulism cases. For the first time, differences in glycosylation profiles of the flagella could be linked to differences in the gene content of the FGI. Conclusion Proteolytic C. botulinum has a stable genome backbone containing specific regions of genetic heterogeneity. These include the neurotoxin gene cluster and the FGI, each having evolved independently of each other and the remainder of the genetic complement. Analysis of these genetic components provides a high degree of discrimination of strains of proteolytic C. botulinum, and is suitable for clinical and forensic investigations of botulism outbreaks. PMID:19298644

Independent evolution of neurotoxin and flagellar genetic loci in proteolytic Clostridium botulinum.

PubMed

Carter, Andrew T; Paul, Catherine J; Mason, David R; Twine, Susan M; Alston, Mark J; Logan, Susan M; Austin, John W; Peck, Michael W

2009-03-19

Proteolytic Clostridium botulinum is the causative agent of botulism, a severe neuroparalytic illness. Given the severity of botulism, surprisingly little is known of the population structure, biology, phylogeny or evolution of C. botulinum. The recent determination of the genome sequence of C. botulinum has allowed comparative genomic indexing using a DNA microarray. Whole genome microarray analysis revealed that 63% of the coding sequences (CDSs) present in reference strain ATCC 3502 were common to all 61 widely-representative strains of proteolytic C. botulinum and the closely related C. sporogenes tested. This indicates a relatively stable genome. There was, however, evidence for recombination and genetic exchange, in particular within the neurotoxin gene and cluster (including transfer of neurotoxin genes to C. sporogenes), and the flagellar glycosylation island (FGI). These two loci appear to have evolved independently from each other, and from the remainder of the genetic complement. A number of strains were atypical; for example, while 10 out of 14 strains that formed type A1 toxin gave almost identical profiles in whole genome, neurotoxin cluster and FGI analyses, the other four strains showed divergent properties. Furthermore, a new neurotoxin sub-type (A5) has been discovered in strains from heroin-associated wound botulism cases. For the first time, differences in glycosylation profiles of the flagella could be linked to differences in the gene content of the FGI. Proteolytic C. botulinum has a stable genome backbone containing specific regions of genetic heterogeneity. These include the neurotoxin gene cluster and the FGI, each having evolved independently of each other and the remainder of the genetic complement. Analysis of these genetic components provides a high degree of discrimination of strains of proteolytic C. botulinum, and is suitable for clinical and forensic investigations of botulism outbreaks.

Natural Genetic Variation and Candidate Genes for Morphological Traits in Drosophila melanogaster

PubMed Central

Carreira, Valeria Paula; Mensch, Julián; Hasson, Esteban; Fanara, Juan José

2016-01-01

Body size is a complex character associated to several fitness related traits that vary within and between species as a consequence of environmental and genetic factors. Latitudinal and altitudinal clines for different morphological traits have been described in several species of Drosophila and previous work identified genomic regions associated with such variation in D. melanogaster. However, the genetic factors that orchestrate morphological variation have been barely studied. Here, our main objective was to investigate genetic variation for different morphological traits associated to the second chromosome in natural populations of D. melanogaster along latitudinal and altitudinal gradients in Argentina. Our results revealed weak clinal signals and a strong population effect on morphological variation. Moreover, most pairwise comparisons between populations were significant. Our study also showed important within-population genetic variation, which must be associated to the second chromosome, as the lines are otherwise genetically identical. Next, we examined the contribution of different candidate genes to natural variation for these traits. We performed quantitative complementation tests using a battery of lines bearing mutated alleles at candidate genes located in the second chromosome and six second chromosome substitution lines derived from natural populations which exhibited divergent phenotypes. Results of complementation tests revealed that natural variation at all candidate genes studied, invected, Fasciclin 3, toucan, Reticulon-like1, jing and CG14478, affects the studied characters, suggesting that they are Quantitative Trait Genes for morphological traits. Finally, the phenotypic patterns observed suggest that different alleles of each gene might contribute to natural variation for morphological traits. However, non-additive effects cannot be ruled out, as wild-derived strains differ at myriads of second chromosome loci that may interact epistatically with mutant alleles. PMID:27459710

Polymorphism in xeroderma pigmentosum complementation group C codon 939 and aflatoxin B1-related hepatocellular carcinoma in the Guangxi population.

PubMed

Long, Xi-Dai; Ma, Yun; Zhou, Yuan-Feng; Ma, Ai-Min; Fu, Guo-Hui

2010-10-01

Genetic polymorphisms in DNA repair genes may influence individual variations in DNA repair capacity, and this may be associated with the risk and outcome of hepatocellular carcinoma (HCC) related to aflatoxin B1 (AFB1) exposure. In this study, we focused on the polymorphism of xeroderma pigmentosum complementation group C (XPC) codon 939 (rs#2228001), which is involved in nucleotide excision repair. We conducted a case-control study including 1156 HCC cases and 1402 controls without any evidence of hepatic disease to evaluate the associations between this polymorphism and HCC risk and prognosis in the Guangxi population. AFB1 DNA adduct levels, XPC genotypes, and XPC protein levels were tested with a comparative enzyme-linked immunosorbent assay, TaqMan polymerase chain reaction for XPC genotypes, and immunohistochemistry, respectively. Higher AFB1 exposure was observed among HCC patients versus the control group [odds ratio (OR) = 9.88 for AFB1 exposure years and OR = 6.58 for AFB1 exposure levels]. The XPC codon 939 Gln alleles significantly increased HCC risk [OR = 1.25 (95% confidence interval = 1.03-1.52) for heterozygotes of the XPC codon 939 Lys and Gln alleles (XPC-LG) and OR = 1.81 (95% confidence interval = 1.36-2.40) for homozygotes of the XPC codon 939 Gln alleles (XPC-GG)]. Significant interactive effects between genotypes and AFB1 exposure status were also observed in the joint-effects analysis. This polymorphism, moreover, was correlated with XPC expression levels in cancerous tissues (r = -0.369, P < 0.001) and with the overall survival of HCC patients (the median survival times were 30, 25, and 19 months for patients with homozygotes of the XPC codon 939 Lys alleles, XPC-LG, and XPC-GG, respectively), especially under high AFB1 exposure conditions. Like AFB1 exposure, the XPC codon 939 polymorphism was an independent prognostic factor influencing the survival of HCC. Additionally, this polymorphism multiplicatively interacted with the xeroderma pigmentosum complementation group D codon 751 polymorphism with respect to HCC risk (OR(interaction) = 1.71). These results suggest that the XPC codon 939 polymorphism may be associated with the risk and outcome of AFB1-related HCC in the Guangxi population and may interact with AFB1 exposure in the process of HCC induction by AFB1.

Genetic Code Optimization for Cotranslational Protein Folding: Codon Directional Asymmetry Correlates with Antiparallel Betasheets, tRNA Synthetase Classes.

PubMed

Seligmann, Hervé; Warthi, Ganesh

2017-01-01

A new codon property, codon directional asymmetry in nucleotide content (CDA), reveals a biologically meaningful genetic code dimension: palindromic codons (first and last nucleotides identical, codon structure XZX) are symmetric (CDA = 0), codons with structures ZXX/XXZ are 5'/3' asymmetric (CDA = - 1/1; CDA = - 0.5/0.5 if Z and X are both purines or both pyrimidines, assigning negative/positive (-/+) signs is an arbitrary convention). Negative/positive CDAs associate with (a) Fujimoto's tetrahedral codon stereo-table; (b) tRNA synthetase class I/II (aminoacylate the 2'/3' hydroxyl group of the tRNA's last ribose, respectively); and (c) high/low antiparallel (not parallel) betasheet conformation parameters. Preliminary results suggest CDA-whole organism associations (body temperature, developmental stability, lifespan). Presumably, CDA impacts spatial kinetics of codon-anticodon interactions, affecting cotranslational protein folding. Some synonymous codons have opposite CDA sign (alanine, leucine, serine, and valine), putatively explaining how synonymous mutations sometimes affect protein function. Correlations between CDA and tRNA synthetase classes are weaker than between CDA and antiparallel betasheet conformation parameters. This effect is stronger for mitochondrial genetic codes, and potentially drives mitochondrial codon-amino acid reassignments. CDA reveals information ruling nucleotide-protein relations embedded in reversed (not reverse-complement) sequences (5'-ZXX-3'/5'-XXZ-3').

Isolation and characterization of chromosome-gain and increase-in-ploidy mutants in yeast.

PubMed

Chan, C S; Botstein, D

1993-11-01

We have developed a colony papillation assay for monitoring the copy number of genetically marked chromosomes II and III in Saccharomyces cerevisiae. The unique feature of this assay is that it allows detection of a gain of the marked chromosomes even if there is a gain of the entire set of chromosomes (increase-in-ploidy). This assay was used to screen for chromosome-gain or increase-in-ploidy mutants. Five complementation groups have been defined for recessive mutations that confer an increase-in-ploidy (ipl) phenotype, which, in each case, cosegregates with a temperature-sensitive growth phenotype. Four new alleles of CDC31, which is required for spindle pole body duplication, were also recovered from this screen. Temperature-shift experiments with ipl1 cells show that they suffer severe nondisjunction at 37 degrees. Similar experiments with ipl2 cells show that they gain entire sets of chromosomes and become arrested as unbudded cells at 37 degrees. Molecular cloning and genetic mapping show that IPL1 is a newly identified gene, whereas IPL2 is allelic to BEM2, which is required for normal bud growth.

Genetic risk factors of systemic lupus erythematosus in the Malaysian population: a minireview.

PubMed

Chai, Hwa Chia; Phipps, Maude Elvira; Chua, Kek Heng

2012-01-01

SLE is an autoimmune disease that is not uncommon in Malaysia. In contrast to Malays and Indians, the Chinese seem to be most affected. SLE is characterized by deficiency of body's immune response that leads to production of autoantibodies and failure of immune complex clearance. This minireview attempts to summarize the association of several candidate genes with risk for SLE in the Malaysian population and discuss the genetic heterogeneity that exists locally in Asians and in comparison with SLE in Caucasians. Several groups of researchers have been actively investigating genes that are associated with SLE susceptibility in the Malaysian population by screening possible reported candidate genes across the SLE patients and healthy controls. These candidate genes include MHC genes and genes encoding complement components, TNF, FcγR, T-cell receptors, and interleukins. However, most of the polymorphisms investigated in these genes did not show significant associations with susceptibility to SLE in the Malaysian scenario, except for those occurring in MHC genes and genes coding for TNF-α, IL-1β, IL-1RN, and IL-6.

Genetic Risk Factors of Systemic Lupus Erythematosus in the Malaysian Population: A Minireview

PubMed Central

Chai, Hwa Chia; Phipps, Maude Elvira; Chua, Kek Heng

2012-01-01

SLE is an autoimmune disease that is not uncommon in Malaysia. In contrast to Malays and Indians, the Chinese seem to be most affected. SLE is characterized by deficiency of body's immune response that leads to production of autoantibodies and failure of immune complex clearance. This minireview attempts to summarize the association of several candidate genes with risk for SLE in the Malaysian population and discuss the genetic heterogeneity that exists locally in Asians and in comparison with SLE in Caucasians. Several groups of researchers have been actively investigating genes that are associated with SLE susceptibility in the Malaysian population by screening possible reported candidate genes across the SLE patients and healthy controls. These candidate genes include MHC genes and genes encoding complement components, TNF, FcγR, T-cell receptors, and interleukins. However, most of the polymorphisms investigated in these genes did not show significant associations with susceptibility to SLE in the Malaysian scenario, except for those occurring in MHC genes and genes coding for TNF-α, IL-1β, IL-1RN, and IL-6. PMID:21941582

Interallelic complementation of mutations in propionic acidemia by microinjection of mutant cDNAs into fibroblasts of affected patients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Loyer, M.; Leclerc, D.; Gravel, R.A.

1994-09-01

Propionic acidemia is a rare autosomal recessive disorder resulting from defects of the {alpha} or {beta} subunit of biotin-dependent propionyl-CoA carboxylase (PCC). Mutations are assigned to defects of the PCCA ({alpha} subunit) or PCCB ({beta} subunit) gene through complementation studies after somatic fusion of patient cell lines. About two-thirds of patients with {beta} subunit defects (complementation group pccBC) show interallelic complementation in cell fusion experiments (subgroups pccB and pccC), monitored by the PCC-dependent metabolisms of {sup 14}C-propionate. Most patient cell lines are heteroallelic for two different mutations, leaving ambiguous the identity of the mutation participating in interallelic complementation. To identifymore » the complementing mutations, we have expressed {beta}-subunit cDNAs containing individual mutations by microinjection of the cDNAs in recipient cells from patients with {beta} subunit defects. Correction of the PCC defect was monitored by autoradiography of {sup 14}C-propionate incorporation. In some experiments, cDNAs were co-injected with a plasmid expressing the E. coli lacZ gene as a positive control for successful injection. Two mutations from the pccB subgroup showed complementation when injected into pccC cells; dupKICK140-143 and Pro228Leu. Similarly, two mutations from the pccC subgroup complemented after injection into pccB cells; {Delta}Ile408 and Arg410Trp. No mutation complemented with mutation of the pccBC group which are classified as non-complementing in cell fusion experiments. The results show that the complementing pccB mutations are found in the N-terminal half of the {beta} subunit, while the complementing pccC mutations cluxter at a site in the C-terminal half. The latter site is a candidate for the propionyl-CoA binding site based on sequence identity with a region of transcarboxylase from Propionibacterium shermanii.« less

Genetic and cytogenetic analysis of the fruit fly Rhagoletis cerasi (Diptera: Tephritidae).

PubMed

Kounatidis, Ilias; Papadopoulos, Nikolaos; Bourtzis, Kostas; Mavragani-Tsipidou, Penelope

2008-07-01

The European cherry fruit fly, Rhagoletis cerasi, is a major agricultural pest for which biological, genetic, and cytogenetic information is limited. We report here a cytogenetic analysis of 4 natural Greek populations of R. cerasi, all of them infected with the endosymbiotic bacterium Wolbachia pipientis. The mitotic karyotype and detailed photographic maps of the salivary gland polytene chromosomes of this pest species are presented here. The mitotic metaphase complement consists of 6 pairs of chromosomes, including one pair of heteromorphic sex chromosomes, with the male being the heterogametic sex. The analysis of the salivary gland polytene complement has shown a total of 5 long chromosomes (10 polytene arms) that correspond to the 5 autosomes of the mitotic nuclei and a heterochromatic mass corresponding to the sex chromosomes. The most prominent landmarks of each polytene chromosome, the "weak points", and the unusual asynapsis of homologous pairs of polytene chromosomes at certain regions of the polytene elements are also presented and discussed.

Early Components of the Complement Classical Activation Pathway in Human Systemic Autoimmune Diseases

PubMed Central

Lintner, Katherine E.; Wu, Yee Ling; Yang, Yan; Spencer, Charles H.; Hauptmann, Georges; Hebert, Lee A.; Atkinson, John P.; Yu, C. Yung

2016-01-01

The complement system consists of effector proteins, regulators, and receptors that participate in host defense against pathogens. Activation of the complement system, via the classical pathway (CP), has long been recognized in immune complex-mediated tissue injury, most notably systemic lupus erythematosus (SLE). Paradoxically, a complete deficiency of an early component of the CP, as evidenced by homozygous genetic deficiencies reported in human, are strongly associated with the risk of developing SLE or a lupus-like disease. Similarly, isotype deficiency attributable to a gene copy-number (GCN) variation and/or the presence of autoantibodies directed against a CP component or a regulatory protein that result in an acquired deficiency are relatively common in SLE patients. Applying accurate assay methodologies with rigorous data validations, low GCNs of total C4, and heterozygous and homozygous deficiencies of C4A have been shown as medium to large effect size risk factors, while high copy numbers of total C4 or C4A as prevalent protective factors, of European and East-Asian SLE. Here, we summarize the current knowledge related to genetic deficiency and insufficiency, and acquired protein deficiencies for C1q, C1r, C1s, C4A/C4B, and C2 in disease pathogenesis and prognosis of SLE, and, briefly, for other systemic autoimmune diseases. As the complement system is increasingly found to be associated with autoimmune diseases and immune-mediated diseases, it has become an attractive therapeutic target. We highlight the recent developments and offer a balanced perspective concerning future investigations and therapeutic applications with a focus on early components of the CP in human systemic autoimmune diseases. PMID:26913032

Prepregnancy obesity and complement system activation in early pregnancy and the subsequent development of preeclampsia.

PubMed

Lynch, Anne M; Eckel, Robert H; Murphy, James R; Gibbs, Ronald S; West, Nancy A; Giclas, Patricia C; Salmon, Jane E; Holers, V Michael

2012-05-01

We hypothesized that women who are obese before they become pregnant and also have elevations of complement Bb and C3a in the top quartile in early pregnancy would have the highest risk of preeclampsia compared with a referent group of women who were not obese and had levels of complement less than the top quartile. This was a prospective study of 1013 women recruited at less than 20 weeks' gestation. An EDTA-plasma sample was obtained, and complement fragments were measured using enzyme-linked immunosorbent assays. The data were analyzed using univariable and multivariable logistic regression analysis. Women who were obese with levels of Bb or C3a in the top quartile were 10.0 (95% confidence interval, 3.3-30) and 8.8 (95% confidence interval, 3-24) times, respectively, more likely to develop preeclampsia compared with the referent group. We demonstrate a combined impact of obesity and elevated complement on the development of preeclampsia. Copyright © 2012. Published by Mosby, Inc.

Current issues in medically assisted reproduction and genetics in Europe: research, clinical practice, ethics, legal issues and policy

PubMed Central

Harper, Joyce C; Geraedts, Joep; Borry, Pascal; Cornel, Martina C; Dondorp, Wybo; Gianaroli, Luca; Harton, Gary; Milachich, Tanya; Kääriäinen, Helena; Liebaers, Inge; Morris, Michael; Sequeiros, Jorge; Sermon, Karen; Shenfield, Françoise; Skirton, Heather; Soini, Sirpa; Spits, Claudia; Veiga, Anna; Vermeesch, Joris Robert; Viville, Stéphane; de Wert, Guido; Macek, Milan

2013-01-01

In March 2005, a group of experts from the European Society of Human Genetics and European Society of Human Reproduction and Embryology met to discuss the interface between genetics and assisted reproductive technology (ART), and published an extended background paper, recommendations and two Editorials. Seven years later, in March 2012, a follow-up interdisciplinary workshop was held, involving representatives of both professional societies, including experts from the European Union Eurogentest2 Coordination Action Project. The main goal of this meeting was to discuss developments at the interface between clinical genetics and ARTs. As more genetic causes of reproductive failure are now recognised and an increasing number of patients undergo testing of their genome before conception, either in regular health care or in the context of direct-to-consumer testing, the need for genetic counselling and preimplantation genetic diagnosis (PGD) may increase. Preimplantation genetic screening (PGS) thus far does not have evidence from randomised clinical trials to substantiate that the technique is both effective and efficient. Whole-genome sequencing may create greater challenges both in the technological and interpretational domains, and requires further reflection about the ethics of genetic testing in ART and PGD/PGS. Diagnostic laboratories should be reporting their results according to internationally accepted accreditation standards (International Standards Organisation – ISO 15189). Further studies are needed in order to address issues related to the impact of ART on epigenetic reprogramming of the early embryo. The legal landscape regarding assisted reproduction is evolving but still remains very heterogeneous and often contradictory. The lack of legal harmonisation and uneven access to infertility treatment and PGD/PGS fosters considerable cross-border reproductive care in Europe and beyond. The aim of this paper is to complement previous publications and provide an update of selected topics that have evolved since 2005. PMID:24225486

PpsA-mediated alternative pathway to complement RNase E essentiality in Escherichia coli.

PubMed

Tamura, Masaru; Honda, Naoko; Fujimoto, Hirofumi; Cohen, Stanley N; Kato, Atsushi

2016-07-01

Escherichia coli cells require RNase E, encoded by the essential gene rne, to propagate. The growth properties on different carbon sources of E. coli cells undergoing suppression of RNase E production suggested that reduction in RNase E is associated with decreased expression of phosphoenolpyruvate synthetase (PpsA), which converts pyruvate to phosphoenolpyruvate during gluconeogenesis. Western blotting and genetic complementation confirmed the role of RNase E in PpsA expression. Adventitious ppsA overexpression from a multicopy plasmid was sufficient to restore colony formation of ∆rne E. coli on minimal media containing glycerol or succinate as the sole carbon source. Complementation of ∆rne by ppsA overproduction was observed during growth on solid media but was only partial, and bacteria showed slowed cell division and grew as filamentous chains. We found that restoration of colony-forming ability by ppsA complementation occurred independent of the presence of endogenous RNase G or second-site suppressors of RNase E essentiality. Our investigations demonstrate the role of phosphoryl transfer catalyzable by PpsA as a determinant of RNase E essentiality in E. coli.

Interallelic Complementation at the Suppressor of Forked Locus of Drosophila Reveals Complementation between Suppressor of Forked Proteins Mutated in Different Regions

PubMed Central

Simonelig, M.; Elliott, K.; Mitchelson, A.; O'Hare, K.

1996-01-01

The Su(f) protein of Drosophila melanogaster shares extensive homologies with proteins from yeast (RNA14) and man (77 kD subunit of cleavage stimulation factor) that are required for 3' end processing of mRNA. These homologies suggest that su(f) is involved in mRNA 3' end formation and that some aspects of this process are conserved throughout eukaryotes. We have investigated the genetic and molecular complexity of the su(f) locus. The su(f) gene is transcribed to produce three RNAs and could encode two proteins. Using constructs that contain different parts of the locus, we show that only the larger predicted gene product of 84 kD is required for the wild-type function of su(f). Some lethal alleles of su(f) complement to produce viable combinations. The structures of complementing and noncomplementing su(f) alleles indicate that 84-kD Su(f) proteins mutated in different domains can act in combination for partial su(f) function. Our results suggest protein-protein interaction between or within wild-type Su(f) molecules. PMID:8846900

Breast Cancer Risk Estimation and Personal Insurance: A Qualitative Study Presenting Perspectives from Canadian Patients and Decision Makers

PubMed Central

Dalpé, Gratien; Ngueng Feze, Ida; Salman, Shahad; Joly, Yann; Hagan, Julie; Lévesque, Emmanuelle; Dorval, Véronique; Blouin-Bougie, Jolyane; Amara, Nabil; Dorval, Michel; Simard, Jacques

2017-01-01

Genetic stratification approaches in personalized medicine may considerably improve our ability to predict breast cancer risk for women at higher risk of developing breast cancer. Notwithstanding these advantages, concerns have been raised about the use of the genetic information derived in these processes, outside of the research and medical health care settings, by third parties such as insurers. Indeed, insurance applicants are asked to consent to insurers accessing their medical information (implicitly including genetic) to verify or determine their insurability level, or eligibility to certain insurance products. This use of genetic information may result in the differential treatment of individuals based on their genetic information, which could lead to higher premium, exclusionary clauses or even the denial of coverage. This phenomenon has been commonly referred to as “Genetic Discrimination” (GD). In the Canadian context, where federal Bill S-201, An Act to prohibit and prevent genetic discrimination, has recently been enacted but may be subject to constitutional challenges, information about potential risks to insurability may raise issues in the clinical context. We conducted a survey with women in Quebec who have never been diagnosed with breast cancer to document their perspectives. We complemented the research with data from 14 semi-structured interviews with decision-makers in Quebec to discuss institutional issues raised by the use of genetic information by insurers. Our results provide findings on five main issues: (1) the reluctance to undergo genetic screening test due to insurability concerns, (2) insurers' interest in genetic information, (3) the duty to disclose genetic information to insurers, (4) the disclosure of potential impacts on insurability before genetic testing, and (5) the status of genetic information compared to other health data. Overall, both groups of participants (the women surveyed and the decision-makers interviewed) acknowledged having concerns about GD and reported a need for better communication tools discussing insurability risk. Our conclusions regarding concerns about GD and the need for better communication tools in the clinical setting may be transferable to the broader Canadian context. PMID:28983318

Breast Cancer Risk Estimation and Personal Insurance: A Qualitative Study Presenting Perspectives from Canadian Patients and Decision Makers.

PubMed

Dalpé, Gratien; Ngueng Feze, Ida; Salman, Shahad; Joly, Yann; Hagan, Julie; Lévesque, Emmanuelle; Dorval, Véronique; Blouin-Bougie, Jolyane; Amara, Nabil; Dorval, Michel; Simard, Jacques

2017-01-01

Genetic stratification approaches in personalized medicine may considerably improve our ability to predict breast cancer risk for women at higher risk of developing breast cancer. Notwithstanding these advantages, concerns have been raised about the use of the genetic information derived in these processes, outside of the research and medical health care settings, by third parties such as insurers. Indeed, insurance applicants are asked to consent to insurers accessing their medical information (implicitly including genetic) to verify or determine their insurability level, or eligibility to certain insurance products. This use of genetic information may result in the differential treatment of individuals based on their genetic information, which could lead to higher premium, exclusionary clauses or even the denial of coverage. This phenomenon has been commonly referred to as "Genetic Discrimination" (GD). In the Canadian context, where federal Bill S-201, An Act to prohibit and prevent genetic discrimination , has recently been enacted but may be subject to constitutional challenges, information about potential risks to insurability may raise issues in the clinical context. We conducted a survey with women in Quebec who have never been diagnosed with breast cancer to document their perspectives. We complemented the research with data from 14 semi-structured interviews with decision-makers in Quebec to discuss institutional issues raised by the use of genetic information by insurers. Our results provide findings on five main issues: (1) the reluctance to undergo genetic screening test due to insurability concerns, (2) insurers' interest in genetic information, (3) the duty to disclose genetic information to insurers, (4) the disclosure of potential impacts on insurability before genetic testing, and (5) the status of genetic information compared to other health data. Overall, both groups of participants (the women surveyed and the decision-makers interviewed) acknowledged having concerns about GD and reported a need for better communication tools discussing insurability risk. Our conclusions regarding concerns about GD and the need for better communication tools in the clinical setting may be transferable to the broader Canadian context.

Correlations in the population structure of music, genes and language.

PubMed

Brown, Steven; Savage, Patrick E; Ko, Albert Min-Shan; Stoneking, Mark; Ko, Ying-Chin; Loo, Jun-Hun; Trejaut, Jean A

2014-01-07

We present, to our knowledge, the first quantitative evidence that music and genes may have coevolved by demonstrating significant correlations between traditional group-level folk songs and mitochondrial DNA variation among nine indigenous populations of Taiwan. These correlations were of comparable magnitude to those between language and genes for the same populations, although music and language were not significantly correlated with one another. An examination of population structure for genetics showed stronger parallels to music than to language. Overall, the results suggest that music might have a sufficient time-depth to retrace ancient population movements and, additionally, that it might be capturing different aspects of population history than language. Music may therefore have the potential to serve as a novel marker of human migrations to complement genes, language and other markers.

The amphioxus genome and the evolution of the chordate karyotype

DOE Office of Scientific and Technical Information (OSTI.GOV)

Putnam, Nicholas H.; Butts, Thomas; Ferrier, David E.K.

2008-04-01

Lancelets ('amphioxus') are the modern survivors of an ancient chordate lineage with a fossil record dating back to the Cambrian. We describe the structure and gene content of the highly polymorphic {approx}520 million base pair genome of the Florida lancelet Branchiostoma floridae, and analyze it in the context of chordate evolution. Whole genome comparisons illuminate the murky relationships among the three chordate groups (tunicates, lancelets, and vertebrates), and allow reconstruction of not only the gene complement of the last common chordate ancestor, but also a partial reconstruction of its genomic organization, as well as a description of two genome-wide duplicationsmore » and subsequent reorganizations in the vertebrate lineage. These genome-scale events shaped the vertebrate genome and provided additional genetic variation for exploitation during vertebrate evolution.« less

Correlations in the population structure of music, genes and language

PubMed Central

Brown, Steven; Savage, Patrick E.; Ko, Albert Min-Shan; Stoneking, Mark; Ko, Ying-Chin; Loo, Jun-Hun; Trejaut, Jean A.

2014-01-01

We present, to our knowledge, the first quantitative evidence that music and genes may have coevolved by demonstrating significant correlations between traditional group-level folk songs and mitochondrial DNA variation among nine indigenous populations of Taiwan. These correlations were of comparable magnitude to those between language and genes for the same populations, although music and language were not significantly correlated with one another. An examination of population structure for genetics showed stronger parallels to music than to language. Overall, the results suggest that music might have a sufficient time-depth to retrace ancient population movements and, additionally, that it might be capturing different aspects of population history than language. Music may therefore have the potential to serve as a novel marker of human migrations to complement genes, language and other markers. PMID:24225453

Heterocyte-forming cyanobacteria from Brazilian saline-alkaline lakes.

PubMed

Genuário, Diego Bonaldo; Andreote, Ana Paula Dini; Vaz, Marcelo Gomes Marçal Vieira; Fiore, Marli Fátima

2017-04-01

Studies investigating the diversity of cyanobacteria from tropical environments are scarce, especially those devoted to the isolation and molecular characterization of the isolated strains. Among the Brazilian biomes, Pantanal has mainly been examined through microscopic observation of environmental samples, resulting in lists of morphotypes without any genetic information. Recently, two studies were conducted evaluating the morphologic and genetic diversity of cultured non-heterocytous cyanobacteria in this biome, which resulted in the separation and description of two novel genera. In order to complement the diversity of cultured cyanobacteria from saline-alkaline lakes in Pantanal, the present study is dedicated to the examination of cultured nitrogen-fixing heterocytous cyanobacteria from this extreme and underexplored environment. A total of fourteen cyanobacterial strains were isolated. According to morphological examination they belong to the order Nostocales and to the subsections IV.I and IV.II, according to the International Code of Nomenclature for Algae, Fungi and Plants and the Bergey's Manual of Systematic Bacteriology, respectively. Phylogenetic evaluation of their 16S rRNA gene sequences resulted in the formation of five clusters. Among them, one is clearly related to the genus Anabaenopsis whilst the remaining clusters may represent new genetic lineages. These novel sequences aid in the delimitation of problematic groups, especially those containing sequences belonging to mixed genera. The application of both morphologic and phylogenetic studies has proven to be an important tool in resolving problematic groups in cyanobacteria systematics. This strategy is essential in order to detect novel cyanobacteria genera from other tropical environments. Copyright © 2016 Elsevier Inc. All rights reserved.

Correction of both spontaneous and DEB-induced chromosome instability in Fanconi anemia FA-C cells by FACC cDNA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stavropoulos, D.J.; Tomkins, D.J.; Allingham-Hawkins, D.J.

1994-09-01

Cells from all four Fanconi anemia complementation groups show hypersensitivity to cell-killing by mitomycin C (MMC), diepoxybutane (DEB) and other DNA cross-linking agents, and increased spontaneous and DEB-induced chromosome aberrations (CA). The extent of these phenotypes varies between lymphoblastoid cell lines from different complementation groups. Our data showed that the difference in MMC hypersensitivity and DEB-CA was not always coupled. While 230N (FA-B) had higher DEB-induced CA/cell than 536N (FA-C) (7.42 vs. 4.46 respectively), that latter was much more sensitive to cell-killing by MMC (dose at 10% survival, D{sub 10}: 5.2 vs. 1.2 ng/ml respectively). Strathdes et al. (1992) clonedmore » a cDNA Fanconi anemia complementation group C (FACC) which complemented the hypersensitivity to MMC and DEB cell-killing of FA-C cells (536N) but not cells from the other three complementation groups. The present study was initiated to determine whether chromosome instability in 536N is also complemented by the FACC (FAC3) cDNA. The pREP4-FAC3 vector was transfected into 536N and transfectants selected with hygromycin B. The DEB D{sub 10} of 536N (1.0 {mu}M) was corrected to the control level (16.2 {mu}M for 3TO) by FACC (15.1 {mu}M for 536N-FACC), as previously demonstrated. Chromosome instability (cab, cse, ctb, cte) was determined without and with 0.1 {mu}g/ml DEB treatment. Spontaneous CA of 536N (0.30 aberrations/cell) was corrected to the control level (0.04 for 3TO) by FACC (0.06 for 536N-FACC). Similarly, the DEB-induced CA was corrected (2.74 for 536N vs. 0.06 and 0.02 for 3TO and 536N-FACC respectively). Thus, at least for FA complementation group C, hypersensitivity to cell-killing and chromosome instability are not dissociated and are most likely caused by the same gene defect.« less

Relationship of Circulating C5a and Complement Factor H Levels With Disease Control in Pregnant Women With Asthma.

PubMed

Bohács, Anikó; Bikov, András; Ivancsó, István; Czaller, Ibolya; Böcskei, Renáta; Müller, Veronika; Rigó, János; Losonczy, György; Tamási, Lilla

2016-04-01

Asthma often complicates pregnancy and represents a risk of serious pregnancy complications. The complement system contributes to asthma pathogenesis and is up-regulated in healthy gestation as well. The anaphylatoxin C5a has a major pro-inflammatory role, and the complement factor H is a main soluble regulator protein both in asthma and during pregnancy; however, peripheral levels of these complement factors and their relationship to disease control have not yet been evaluated in pregnant subjects with asthma. The present study aimed to investigate circulating C5a and complement factor H levels in asthma (non-pregnant subjects with asthma; n = 19) and in pregnancy with asthma (pregnant subjects with asthma; n = 22), compared with healthy non-pregnant (n = 21) and healthy pregnant women (n = 13) and to test their relationship to clinical parameters of asthma (lung function, airway inflammation, and symptoms). Circulating C5a levels were higher in the pregnant asthma subject group compared with the healthy non-pregnant, healthy pregnant, and non-pregnant asthma groups: median 2.629 (interquartile range [IQR] 2.257-3.052) ng/mL versus 1.84 (IQR 1.576-2.563), 1.783 (IQR 0.6064-2.786), and 2.024 (IQR 1.232-2.615) ng/mL, respectively (P = .02 in all cases). C5a correlated negatively with FEV1 (r = -0.44, P = .039) and FVC values (r = -0.64, P = .001) in the pregnant asthma group and positively with fraction of exhaled nitric oxide levels in the non-pregnant asthma group (n = 12, r = 0.78, P = .004). Complement factor H levels were elevated in both the healthy pregnant and pregnant asthma subject groups compared with the healthy non-pregnant group (median 1,082 [IQR 734.9-1,224] and 910.7 [IQR 614.5-1076] μg/mL vs. 559.7 [IQR 388.7-783.1] μg/mL, P = .002 and P = .004, respectively) but not in the pregnant asthma group compared with the non-pregnant asthma group (median 687.4 [IQR 441.6-947.6] μg/mL, P = .10). Asthma during pregnancy increases the circulating level of pro-inflammatory C5a, which is accompanied by impaired lung function and partly counteracted by the gestation-specific elevation of regulatory complement factor H level (detected in pregnancy both in healthy and subjects with asthma). Copyright © 2016 by Daedalus Enterprises.

Complement activation and choriocapillaris loss in early AMD: Implications for pathophysiology and therapy

PubMed Central

Whitmore, S.Scott; Sohn, Elliott H.; Chirco, Kathleen R.; Drack, Arlene V.; Stone, Edwin M.; Tucker, Budd A.; Mullins, Robert F.

2015-01-01

Age-related macular degeneration (AMD) is a common and devastating disease that can result in severe visual dysfunction. Over the last decade, great progress has been made in identifying genetic variants that contribute to AMD, many of which lie in genes involved in the complement cascade. In this review we discuss the significance of complement activation in AMD, particularly with respect to the formation of the membrane attack complex in the aging choriocapillaris. We review the clinical, histological and biochemical data that indicate that vascular loss in the choroid occurs very early in the pathogenesis of AMD, and discuss the potential impact of vascular dropout on the retinal pigment epithelium, Bruch's membrane and the photoreceptor cells. Finally, we present a hypothesis for the pathogenesis of early AMD and consider the implications of this model on the development of new therapies. PMID:25486088

Complement activation and choriocapillaris loss in early AMD: implications for pathophysiology and therapy.

PubMed

Whitmore, S Scott; Sohn, Elliott H; Chirco, Kathleen R; Drack, Arlene V; Stone, Edwin M; Tucker, Budd A; Mullins, Robert F

2015-03-01

Age-related macular degeneration (AMD) is a common and devastating disease that can result in severe visual dysfunction. Over the last decade, great progress has been made in identifying genetic variants that contribute to AMD, many of which lie in genes involved in the complement cascade. In this review we discuss the significance of complement activation in AMD, particularly with respect to the formation of the membrane attack complex in the aging choriocapillaris. We review the clinical, histological and biochemical data that indicate that vascular loss in the choroid occurs very early in the pathogenesis of AMD, and discuss the potential impact of vascular dropout on the retinal pigment epithelium, Bruch's membrane and the photoreceptor cells. Finally, we present a hypothesis for the pathogenesis of early AMD and consider the implications of this model on the development of new therapies. Copyright © 2014 Elsevier Ltd. All rights reserved.

Development and Use of a Serum Bactericidal Assay Using Pooled Human Complement To Assess Responses to a Meningococcal Group A Conjugate Vaccine in African Toddlers

PubMed Central

Lynn, Freyja; Mocca, Brian; Borrow, Ray; Findlow, Helen; Hassan-King, Musa; Preziosi, Marie-Pierre; Idoko, Olubukola; Sow, Samba; Kulkarni, Prasad; LaForce, F. Marc

2014-01-01

A meningococcal group A polysaccharide (PS) conjugate vaccine (PsA-TT) has been developed for African countries affected by epidemic meningitis caused by Neisseria meningitidis. Complement-mediated serum bactericidal antibody (SBA) assays are used to assess protective immune responses to meningococcal vaccination. Human complement (hC′) was used in early studies demonstrating antibody-mediated protection against disease, but it is difficult to obtain and standardize. We developed and evaluated a method for sourcing hC′ and then used the SBA assay with hC′ (hSBA) to measure bactericidal responses to PsA-TT vaccination in 12- to 23-month-old African children. Sera with active complement from 100 unvaccinated blood donors were tested for intrinsic bactericidal activity, SBA titer using rabbit complement (rSBA), and anti-group A PS antibody concentration. Performance criteria and pooling strategies were examined and then verified by comparisons of three independently prepared hC′ lots in two laboratories. hSBA titers of clinical trial sera were then determined using this complement sourcing method. Two different functional antibody tests were necessary for screening hC′. hSBA titers determined using three independent lots of pooled hC′ were within expected assay variation among lots and between laboratories. In African toddlers, PsA-TT elicited higher hSBA titers than meningococcal polysaccharide or Hib vaccines. PsA-TT immunization or PS challenge of PsA-TT-primed subjects resulted in vigorous hSBA memory responses, and titers persisted in boosted groups for over a year. Quantifying SBA using pooled hC′ is feasible and showed that PsA-TT was highly immunogenic in African toddlers. PMID:24671551

Visceral perfusion abnormalities following complement activation. Clues to the mediators of organ ischemia in trauma and sepsis. First place winner: Conrad Jobst Award.

PubMed

Schirmer, W J; Schirmer, J M; Naff, G B; Fry, D E

1988-12-01

Complement, activated during infection and injury, has been implicated as a mediator of microvascular injury and obstruction. This study examines how two potent activators of complement, zymosan, and cobra venom factor (CVF), affect systemic and visceral perfusion. Rats were injected with either saline (1 ml/kg), zymosan (5 mg/kg) or CVF (5 units/kg) at t = 0 and 30 minutes. Thermodilution cardiac output, mean arterial pressure, heart rate, systemic vascular resistance, and hematocrit were determined at t = 2 hours. Effective hepatic and renal blood flows, by clearance of galactose and p-aminohippurate respectively, were determined over the next hour. The per cent change in total hemolytic complement from t = 0 to t = 3 hours was determined by immune hemolysis of sheep erythrocytes. There was no difference in systemic hemodynamic parameters between the three groups. Hepatic blood flow was depressed in both the zymosan (3.83 +/- 0.23 ml/min/100 g) and CVF (3.72 +/- 0.20 ml/min/100 g) groups compared with controls (4.62 +/- 0.19 ml/min/100 g, P less than 0.05). Renal blood flow in the zymosan-treated group (6.40 +/- 0.24 ml/min/100 g) increased over control (4.80 +/- 0.40 ml/min/100 g, P less than 0.05) but was unchanged in the CVF group (5.06 +/- 0.23 ml/min/100 g). The amount of complement activated correlated with the change in hepatic (r = -0.419, P less than 0.05) but not renal (r = -0.008, P = 0.917) flow. Complement activation may occupy a proximal position in the pathogenesis of hepatic ischemia associated with trauma and sepsis.

Enhancing Undergraduate Teaching and Research with a "Drosophila" Virginizing System

ERIC Educational Resources Information Center

Venema, Dennis R.

2006-01-01

Laboratory exercises using "Drosophila" crosses are an effective pedagogical method to complement traditional lecture and textbook presentations of genetics. Undergraduate thesis research is another common setting for using "Drosophila." A significant barrier to using "Drosophila" for undergraduate teaching or research is the time and skill…

Complement activation and liver impairment in trichloroethylene-sensitized BALB/c mice.

PubMed

Zhang, Jiaxiang; Zha, Wansheng; Wang, Feng; Jiang, Tao; Xu, Shuhai; Yu, Junfeng; Zhou, Chengfan; Shen, Tong; Wu, Changhao; Zhu, Qixing

2013-01-01

Our recent studies have shown that trichloroethylene (TCE) was able to induce multisystem injuries in the form of occupational medicamentosa-like dermatitis, including skin, kidney, and liver damages. However, the role of complement activation in the immune-mediated liver injury is not known. This study examined the role of complement activation in the liver injury in a mouse model of TCE-induced sensitization. Treatment of female BALB/c mice with TCE under specific dosing protocols resulted in skin inflammation and sensitization. Skin edema and erythema occurred in TCE-sensitized groups. Trichloroethylene sensitization produced liver histopathological lesions, increased serum alanine aminotransferase, aspartate transaminase activities, and the relative liver weight. The concentrations of serum complement components C3a-desArg, C5a-desArg, and C5b-9 were significantly increased in 24-hour, 48-hour, and 72-hour sensitization-positive groups treated with TCE and peaked in the 72-hour sensitization-positive group. Depositions of C3a, C5a, and C5b-9 into the liver tissue were also revealed by immunohistochemistry. Immunofluorescence further verified high C5b-9 expression in 24-hour, 48-hour, and 72-hour sensitization-positive groups in response to TCE treatment. Reverse transcription-polymerase chain reaction detected C3 messenger RNA expression in the liver, and this was significantly increased in 24-hour and 48-hour sensitization-positive groups with a transient reduction at 72 hours. These results provide the first experimental evidence that complement activation may play a key role in the generation and progression of immune-mediated hepatic injury by exposure to TCE.

Transcriptome Analysis of the Innate Immunity-Related Complement System in Spleen Tissue of Ctenopharyngodon idella Infected with Aeromonas hydrophila

PubMed Central

Dang, Yunfei; Xu, Xiaoyan; Shen, Yubang; Hu, Moyan; Zhang, Meng; Li, Lisen; Lv, Liqun; Li, Jiale

2016-01-01

The grass carp (Ctenopharyngodon idella) is an important commercial farmed herbivorous fish species in China, but is susceptible to Aeromonas hydrophila infections. In the present study, we performed de novo RNA-Seq sequencing of spleen tissue from specimens of a disease-resistant family, which were given intra-peritoneal injections containing PBS with or without a dose of A. hydrophila. The fish were sampled from the control group at 0 h, and from the experimental group at 4, 8, 12, 24, 48 and 72 h. 122.18 million clean reads were obtained from the normalized cDNA libraries; these were assembled into 425,260 contigs and then 191,795 transcripts. Of those, 52,668 transcripts were annotated with the NCBI Nr database, and 41,347 of the annotated transcripts were assigned into 90 functional groups. 20,569 unigenes were classified into six main categories, including 38 secondary KEGG pathways. 2,992 unigenes were used in the analysis of differentially expressed genes (DEGs). 89 of the putative DEGs were related to the immune system and 41 of them were involved in the complement and coagulation cascades pathway. This study provides insights into the complement and complement-related pathways involved in innate immunity, through expression profile analysis of the genomic resources in C. idella. We conclude that complement and complement-related genes play important roles during defense against A. hydrophila infection. The immune response is activated at 4 h after the bacterial injections, indicating that the complement pathways are activated at the early stage of bacterial infection. The study has improved our understanding of the immune response mechanisms in C. idella to bacterial pathogens. PMID:27383749

Atypical Hemolytic Uremic Syndrome: A Meta-Analysis of Case Reports Confirms the Prevalence of Genetic Mutations and the Shift of Treatment Regimens.

PubMed

Krishnappa, Vinod; Gupta, Mohit; Elrifai, Mohamed; Moftakhar, Bahar; Ensley, Michael J; Vachharajani, Tushar J; Sethi, Sidharth Kumar; Raina, Rupesh

2018-04-01

Atypical hemolytic uremic syndrome (aHUS) is a rare life-threatening thrombotic microangiopathy (TMA) affecting multiple organ systems. Recently, aHUS has been shown to be associated with uncontrolled complement activation due to mutations in the alternative pathway of complement components paving the way for targeted drug therapy. By meta-analysis of case reports, we discuss the impact of new treatment strategies on the resolution time of aHUS symptoms and mortality, and the distribution of genetic mutations. A PubMed/Medline search was conducted for "atypical hemolytic uremic syndrome" case reports published between November 2005 and November 2015. R Version 3.2.2 was used to calculate descriptive statistics and perform univariate analyses. Wilcoxon rank-sum test was used to compare time to symptoms resolution, creatinine and platelet count normalization across the treatment and mutation carrier groups. A total of 259 aHUS patients were reported in 176 articles between 2005 and 2015. In the last 5-year period compared to the precedent, there was an increase in the number of aHUS cases reported (180 vs. 79 cases) and the use of eculizumab also increased (6.3% to 46.1%, P < 0.000), although plasma exchange usage did not change (P = 0.281). CFH antibodies were present in a significantly higher number of patients treated with plasma exchange therapy (19.1%, P = 0.000) while none of the non-plasma exchange therapy group had CFH antibodies. Most common mutation was CFH (50%, 69/139) followed by CFHR1 (35%, 30/85), MCP (22.8%, 23/101) and CFI (16.6%, 17/102). Time to symptoms resolution and serum creatinine or platelet count normalization were not significantly different between eculizumab and non-eculizumab group (P = 0.166, P = 0.361, P = 0.834), and between plasma exchange and non-plasma exchange group (P = 0.150, P = 0.135, P = 0.784). However, both eculizumab and plasma exchange groups had early platelet recovery (22 vs. 30 days and 25.5 vs. 32.5 days), faster creatinine normalization (27 vs. 30.5 days and 27 vs. 37 days) and interestingly, a longer period for symptoms resolution (45.5 vs. 21 days and 30 vs. 18.5 days) compared to non-eculizumab and non-plasma exchange groups. Mortality rate decreased with the use of eculizumab significantly (P = 0.045) compared to non-eculizumab group and there was no change in mortality rate with the use of plasma exchange therapy (P = 0.760) compared to non-plasma exchange group. Plasma exchange continues to be the initial treatment of choice for aHUS. Although significant reduction in the mortality rate was noted with the use of eculizumab, there were no differences in time to resolution of symptoms or serum creatinine or platelet normalization with the use of either eculizumab or plasma therapy. Atypical HUS is acute and life-threatening, so plasma exchange may be initiated before the confirmed diagnosis and in patients positive for CFH antibodies. Eculizumab therapy should be considered once aHUS is confirmed by genetic testing. © 2017 International Society for Apheresis, Japanese Society for Apheresis, and Japanese Society for Dialysis Therapy.

The gene for the ataxia-telagiectasia variant, Nijmegen breakage syndrome, maps to a 1-cM interval on chromosome 8q21

DOE Office of Scientific and Technical Information (OSTI.GOV)

Saar, K.; Stumm, M.; Wegner, R.D.

1997-03-01

Nijmegen breakage syndrome (NBS; Seemanova II syndrome) and Berlin breakage syndrome (BBS), also known as ataxia-telangiectasia variants, are two clinically indistinguishable autosomal recessive familial cancer syndromes that share with ataxia-telangiectasia similar cellular, immunological, and chromosomal but not clinical findings. Classification in NBS and BBS was based on complementation of their hypersensitivity to ionizing radiation in cell-fusion experiments. Recent investigations have questioned the former classification into two different disease entities, suggesting that NBS/BBS is caused by mutations in a single radiosensitivity gene. We now have performed a whole-genome screen in 14 NBS/BBS families and have localized the gene for NBS/BBS tomore » a 1-cM interval on chromosome 8q21, between markers D8S271 and D8S270, with a peak LOD score of 6.86 at D8S1811. This marker also shows strong allelic association to both Slavic NBS and German BBS patients, suggesting the existence of one major mutation of Slavic origin. Since the same allele is seen in both former complementation groups, genetic homogeneity of NBS/BBS can be considered as proved. 21 refs., 2 figs., 2 tabs.« less

Isolation and characterization of Arabidopsis mutants defective in the induction of ethylene biosynthesis by cytokinin

NASA Technical Reports Server (NTRS)

Vogel, J. P.; Schuerman, P.; Woeste, K.; Brandstatter, I.; Kieber, J. J.; Evans, M. L. (Principal Investigator)

1998-01-01

Cytokinins elevate ethylene biosynthesis in etiolated Arabidopsis seedlings via a post-transcriptional modification of one isoform of the key biosynthetic enzyme ACC synthase. In order to begin to dissect the signaling events leading from cytokinin perception to this modification, we have isolated a series of mutants that lack the ethylene-mediated triple response in the presence of cytokinin due to their failure to increase ethylene biosynthesis. Analysis of genetic complementation and mapping revealed that these Cin mutants (cytokinin-insensitive) represent four distinct complementation groups, one of which, cin4, is allelic to the constitutive photomorphogenic mutant fus9/cop10. The Cin mutants have subtle effects on the morphology of adult plants. We further characterized the Cin mutants by analyzing ethylene biosynthesis in response to various other inducers and in adult tissues, as well as by assaying additional cytokinin responses. The cin3 mutant did not disrupt ethylene biosynthesis under any other conditions, nor did it disrupt any other cytokinin responses. Only cin2 disrupted ethylene biosynthesis in multiple circumstances. cin1 and cin2 made less anthocyanin in response to cytokinin. cin1 also displayed reduced shoot initiation in tissue culture in response to cytokinin, suggesting that it affects a cytokinin signaling element.

Molecular Genetic Analysis of Chlamydia Species.

PubMed

Sixt, Barbara S; Valdivia, Raphael H

2016-09-08

Species of Chlamydia are the etiologic agent of endemic blinding trachoma, the leading cause of bacterial sexually transmitted diseases, significant respiratory pathogens, and a zoonotic threat. Their dependence on an intracellular growth niche and their peculiar developmental cycle are major challenges to elucidating their biology and virulence traits. The last decade has seen tremendous advances in our ability to perform a molecular genetic analysis of Chlamydia species. Major achievements include the generation of large collections of mutant strains, now available for forward- and reverse-genetic applications, and the introduction of a system for plasmid-based transformation enabling complementation of mutations; expression of foreign, modified, or reporter genes; and even targeted gene disruptions. This review summarizes the current status of the molecular genetic toolbox for Chlamydia species and highlights new insights into their biology and new challenges in the nascent field of Chlamydia genetics.

Clinical symptoms and DNA repair characteristics of xeroderma pigmentosum patients from Germany

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thielmann, H.W.; Popanda, O.; Edler, L.

1991-07-01

Sixty-one xeroderma pigmentosum (XP) patients living in the Federal Republic of Germany were investigated. Clinical symptoms were correlated with DNA repair parameters measured in fibroblasts grown from skin biopsies. Classification according to the international complementation groups revealed that of the 61 patients 3 belonged to group A, 26 to group C, 16 to group D, 3 to group E, and 2 to group F; 11 were of the XP variant type. A striking clinical aspect was the frequency of histogenetically different skin tumors varying from one XP complementation group to the other: squamous and basal cell carcinomas predominated in XPmore » group C; lentigo maligna melanomas were most frequent in group D; basal cell carcinomas occurred preferentially in group E and XP variants. Three DNA repair parameters were determined for 46 fibroblast strains: colony-forming ability (D0); DNA repair synthesis (G0); and DNA-incising capacity (E0). Dose-response experiments with up to 13 dose levels were performed throughout to achieve sufficient experimental accuracy. DNA-damaging treatments included UV light, the 'UV-like' carcinogen N-acetoxy-2-acetylaminofluorene, and the alkylating carcinogens methyl methanesulfonate and N-methyl-N-nitrosourea. Comparison of clinical signs and repair data was made on the basis of D0, G0, and E0 values of both individual cell strains and weighted means of XP complementation groups. Despite considerable clinical and biochemical heterogeneity within complementation groups distinctive features emerged. In general, D0, G0, and E0 values of all XP strains investigated, including XP variants, were found to be reduced upon treatment with UV light or N-acetoxy-2-acetylaminofluorene.« less

Precision medicine: does ethnicity information complement genotype-based prescribing decisions?

PubMed Central

Shah, Rashmi R.; Gaedigk, Andrea

2017-01-01

Inter-ethnic differences in drug response are all too well known. These are underpinned by a number of factors, including pharmacogenetic differences across various ethnic populations. Precision medicine relies on genotype-based prescribing decisions with the aim of maximizing efficacy and mitigating the risks. When there is no access to genotyping tests, ethnicity is frequently regarded as a proxy of the patient’s probable genotype on the basis of overall population-based frequency of genetic variations in the ethnic group the patient belongs to, with some variations being ethnicity-specific. However, ever-increasing transcontinental migration of populations and the resulting admixing of populations have undermined the utility of self-identified ethnicity in predicting the genetic ancestry, and therefore the genotype, of the patient. An example of the relevance of genetic ancestry of a patient is the inadequate performance of European-derived pharmacogenetic dosing algorithms of warfarin in African Americans, Brazilians and Caribbean Hispanics. Consequently, genotyping a patient potentially requires testing for all known clinically actionable variants that the patient may harbour, and new variants that are likely to be identified using state-of the art next-generation sequencing-based methods. Furthermore, self-identified ethnicity is associated with a number of ethnicity-related attributes and non-genetic factors that potentially influence the risk of phenoconversion (genotype–phenotype discordance), which may adversely impact the success of genotype-based prescribing decisions. Therefore, while genotype-based prescribing decisions are important in implementing precision medicine, ethnicity should not be disregarded. PMID:29318005

Advances in DNA sequencing technologies for high resolution HLA typing.

PubMed

Cereb, Nezih; Kim, Hwa Ran; Ryu, Jaejun; Yang, Soo Young

2015-12-01

This communication describes our experience in large-scale G group-level high resolution HLA typing using three different DNA sequencing platforms - ABI 3730 xl, Illumina MiSeq and PacBio RS II. Recent advances in DNA sequencing technologies, so-called next generation sequencing (NGS), have brought breakthroughs in deciphering the genetic information in all living species at a large scale and at an affordable level. The NGS DNA indexing system allows sequencing multiple genes for large number of individuals in a single run. Our laboratory has adopted and used these technologies for HLA molecular testing services. We found that each sequencing technology has its own strengths and weaknesses, and their sequencing performances complement each other. HLA genes are highly complex and genotyping them is quite challenging. Using these three sequencing platforms, we were able to meet all requirements for G group-level high resolution and high volume HLA typing. Copyright © 2015 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

Identification of auxotrophic mutants of the yeast Kluyveromyces marxianus by non-homologous end joining-mediated integrative transformation with genes from Saccharomyces cerevisiae.

PubMed

Yarimizu, Tohru; Nonklang, Sanom; Nakamura, Junpei; Tokuda, Shuya; Nakagawa, Takaaki; Lorreungsil, Sasithorn; Sutthikhumpha, Surasit; Pukahuta, Charida; Kitagawa, Takao; Nakamura, Mikiko; Cha-Aim, Kamonchai; Limtong, Savitree; Hoshida, Hisashi; Akada, Rinji

2013-12-01

The isolation and application of auxotrophic mutants for gene manipulations, such as genetic transformation, mating selection and tetrad analysis, form the basis of yeast genetics. For the development of these genetic methods in the thermotolerant fermentative yeast Kluyveromyces marxianus, we isolated a series of auxotrophic mutants with defects in amino acid or nucleic acid metabolism. To identify the mutated genes, linear DNA fragments of nutrient biosynthetic pathway genes were amplified from Saccharomyces cerevisiae chromosomal DNA and used to directly transform the K. marxianus auxotrophic mutants by random integration into chromosomes through non-homologous end joining (NHEJ). The appearance of transformant colonies indicated that the specific S. cerevisiae gene complemented the K. marxianus mutant. Using this interspecific complementation approach with linear PCR-amplified DNA, we identified auxotrophic mutations of ADE2, ADE5,7, ADE6, HIS2, HIS3, HIS4, HIS5, HIS6, HIS7, LYS1, LYS2, LYS4, LYS9, LEU1, LEU2, MET2, MET6, MET17, TRP3, TRP4 and TRP5 without the labour-intensive requirement of plasmid construction. Mating, sporulation and tetrad analysis techniques for K. marxianus were also established. With the identified auxotrophic mutant strains and S. cerevisiae genes as selective markers, NHEJ-mediated integrative transformation with PCR-amplified DNA is an attractive system for facilitating genetic analyses in the yeast K. marxianus. Copyright © 2013 John Wiley & Sons, Ltd.

21 CFR 866.5320 - Properdin factor B immuno-logical test system.

Code of Federal Regulations, 2012 CFR

2012-04-01

... involvement of the alternative to the classical pathway of activation of complement (a group of plasma... the skin). Other diseases in which the alternate pathway of complement activation has been implicated...

21 CFR 866.5320 - Properdin factor B immuno-logical test system.

Code of Federal Regulations, 2014 CFR

2014-04-01

... involvement of the alternative to the classical pathway of activation of complement (a group of plasma... the skin). Other diseases in which the alternate pathway of complement activation has been implicated...

21 CFR 866.5320 - Properdin factor B immuno-logical test system.

Code of Federal Regulations, 2013 CFR

2013-04-01

... involvement of the alternative to the classical pathway of activation of complement (a group of plasma... the skin). Other diseases in which the alternate pathway of complement activation has been implicated...

Theory, Method, and Triangulation in the Study of Street Children.

ERIC Educational Resources Information Center

Lucchini, Riccardo

1996-01-01

Describes how a comparative study of street children in Montevideo (Uruguay), Rio de Janeiro, and Mexico City contributes to a synergism between theory and method. Notes how theoretical approaches of symbolic interactionism, genetic structuralism, and habitus theory complement interview, participant observation, and content analysis methods;…

Genetic and Medical Considerations of Autism: A Literature Review.

ERIC Educational Resources Information Center

Silver, Kathi O.

This literature review, from 1990 to the present, discusses the characteristics of autism and the comorbidity of mental retardation and autism. Specific medical syndromes that complement the heterogeneity concept are described, including epilepsy, fragile X syndrome, Rett syndrome, tuberous sclerosis, and Asperger syndrome. The paper presents some…

21 CFR 866.5240 - Complement components immunological test system.

Code of Federal Regulations, 2012 CFR

2012-04-01

.... 866.5240 Section 866.5240 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... complement components C1q, C1r, C1s, C2, C3, C4, C5, C6, C7, C8, and C9, in serum, other body fluids, and tissues. Complement is a group of serum proteins which destroy infectious agents. Measurements of these...

21 CFR 866.5240 - Complement components immunological test system.

Code of Federal Regulations, 2011 CFR

2011-04-01

.... 866.5240 Section 866.5240 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... complement components C1q, C1r, C1s, C2, C3, C4, C5, C6, C7, C8, and C9, in serum, other body fluids, and tissues. Complement is a group of serum proteins which destroy infectious agents. Measurements of these...

21 CFR 866.5240 - Complement components immunological test system.

Code of Federal Regulations, 2013 CFR

2013-04-01

.... 866.5240 Section 866.5240 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... complement components C1q, C1r, C1s, C2, C3, C4, C5, C6, C7, C8, and C9, in serum, other body fluids, and tissues. Complement is a group of serum proteins which destroy infectious agents. Measurements of these...

21 CFR 866.5240 - Complement components immunological test system.

Code of Federal Regulations, 2014 CFR

2014-04-01

.... 866.5240 Section 866.5240 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... complement components C1q, C1r, C1s, C2, C3, C4, C5, C6, C7, C8, and C9, in serum, other body fluids, and tissues. Complement is a group of serum proteins which destroy infectious agents. Measurements of these...

Molecular signatures of fossil leaves provide unexpected new evidence for extinct plant relationships.

PubMed

Vajda, Vivi; Pucetaite, Milda; McLoughlin, Stephen; Engdahl, Anders; Heimdal, Jimmy; Uvdal, Per

2017-08-01

Gene sequences form the primary basis for understanding the relationships among extant plant groups, but genetic data are unavailable from fossils to evaluate the affinities of extinct taxa. Here we show that geothermally resistant fossil cuticles of seed-bearing plants, analysed with Fourier transform infrared (FTIR) spectroscopy and hierarchical cluster analysis (HCA), retain biomolecular suites that consistently distinguish major taxa even after experiencing different diagenetic histories. Our results reveal that similarities between the cuticular biochemical signatures of major plant groups (extant and fossil) are mostly consistent with recent phylogenetic hypotheses based on molecular and morphological data. Our novel chemotaxonomic data also support the hypothesis that the extinct Nilssoniales and Bennettitales are closely allied, but only distantly related to Cycadales. The chemical signature of the cuticle of Czekanowskia (Leptostrobales) is strongly similar to that of Ginkgo leaves and supports a close evolutionary relationship between these groups. Finally, our results also reveal that the extinct putative araucariacean, Allocladus, when analysed through HCA, is grouped closer to Ginkgoales than to conifers. Thus, in the absence of modern relatives yielding molecular information, FTIR spectroscopy provides valuable proxy biochemical data complementing morphological characters to distinguish fossil taxa and to help elucidate extinct plant relationships.

A gene involved in control of human cellular senescence on human chromosome 1q

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hensler, P.J.; Pereira-Smith, O.M.; Annab, L.A.

1994-04-01

Normal cells in culture exhibit limited division potential and have been used as a model for cellular senescence. In contrast, tumor-derived or carcinogen- or virus-transformed cells are capable of indefinite division. Fusion of normal human diploid fibroblasts with immortal human cells yielded hybrids having limited life spans, indicating that cellular senescence was dominant. Fusions of various immortal human cell lines with each other led to the identification of four complementation groups for indefinite division. The purpose of this study was to determine whether human chromosome 1 could complement the recessive immortal defect of human cell lines assigned to one ofmore » the four complementation groups. Using microcell fusion, the authors introduced a single normal human chromosome 1 into immortal human cell lines representing the complementation groups and determined that it caused loss of proliferative potential of an osteosarcoma-derived cell line (TE85), a cytomegalovirus-transformed lung fibroblast cell line (CMV-Mj-HEL-1), and a Ki-ras[sup +]-transformed derivative of TE85 (143B TK[sup [minus

The Role of Frequency on the Acquisition of L2 English Infinitive and Gerund Complements by L1 Thai Learners

ERIC Educational Resources Information Center

Keawchaum, Raksina; Pongpairoj, Nattama

2017-01-01

This study investigated how frequency influenced acquisition of L2 English infinitive and gerund complements among L1 Thai learners. Participants were separated into low and high proficiency groups based on their CU-TEP scores. Each group consisted of 30 participants. Data were collected using the Word Selection Task (WST) and the Grammaticality…

Complement-fixing properties of antinuclear antibodies distinguish drug-induced lupus from systemic lupus erythematosus.

PubMed

Rubin, R L; Teodorescu, M; Beutner, E H; Plunkett, R W

2004-01-01

The immunofluorescence antinuclear antibody (ANA) test has been widely used to monitor autoimmune disease, but its value for diagnostic purposes is compromised by low specificity and high prevalence in disease-free individuals. The capacity of autoantibodies to fix serum complement proteins when bound to antigen is an important effector function because this property is associated with acute and chronic inflammatory processes. The current study evaluates the complement-fixing properties of antinuclear antibodies (CANA) in three well-defined and clinically-related patient groups: systemic lupus erythematosus (SLE), drug-induced lupus (DIL) and drug-induced autoimmunity (DIA). Of 20 patients diagnosed with SLE, 90% displayed complement-fixing ANA while this feature was present in only two of 18 patients with DIL and no patients with DIA without associated disease even though the mean ANA titres were similar among these patient groups. CANA was significantly correlated with anti-Sm activity. Because SLE but not DIL or DIA can be a life-threatening disease associated with complement consumption in vivo, these results demonstrate that measurement of CANA is a diagnostically useful tool and may have immunopathologic implications.

The Group B Streptococcus–Secreted Protein CIP Interacts with C4, Preventing C3b Deposition via the Lectin and Classical Complement Pathways

PubMed Central

Pietrocola, Giampiero; Rindi, Simonetta; Rosini, Roberto; Buccato, Scilla

2016-01-01

The group B Streptococcus (GBS) is a leading cause of neonatal invasive disease. GBS bacteria are surrounded by a thick capsular polysaccharide that is a potent inhibitor of complement deposition via the alternative pathway. Several of its surface molecules can however activate the classical and lectin complement pathways, rendering this species still vulnerable to phagocytic killing. In this study we have identified a novel secreted protein named complement interfering protein (CIP) that downregulates complement activation via the classical and lectin pathways, but not the alternative pathway. The CIP protein showed high affinity toward C4b and inhibited its interaction with C2, presumably preventing the formation of the C4bC2a convertase. Addition of recombinant CIP to GBS cip-negative bacteria resulted in decreased deposition of C3b on their surface and in diminished phagocytic killing in a whole-blood assay. Our data reveal a novel strategy exploited by GBS to counteract innate immunity and could be valuable for the development of anti-infective agents against this important pathogen. PMID:26608922

Genome-Wide Variation Patterns Uncover the Origin and Selection in Cultivated Ginseng (Panax ginseng Meyer).

PubMed

Li, Ming-Rui; Shi, Feng-Xue; Li, Ya-Ling; Jiang, Peng; Jiao, Lili; Liu, Bao; Li, Lin-Feng

2017-09-01

Chinese ginseng (Panax ginseng Meyer) is a medicinally important herb and plays crucial roles in traditional Chinese medicine. Pharmacological analyses identified diverse bioactive components from Chinese ginseng. However, basic biological attributes including domestication and selection of the ginseng plant remain under-investigated. Here, we presented a genome-wide view of the domestication and selection of cultivated ginseng based on the whole genome data. A total of 8,660 protein-coding genes were selected for genome-wide scanning of the 30 wild and cultivated ginseng accessions. In complement, the 45s rDNA, chloroplast and mitochondrial genomes were included to perform phylogenetic and population genetic analyses. The observed spatial genetic structure between northern cultivated ginseng (NCG) and southern cultivated ginseng (SCG) accessions suggested multiple independent origins of cultivated ginseng. Genome-wide scanning further demonstrated that NCG and SCG have undergone distinct selection pressures during the domestication process, with more genes identified in the NCG (97 genes) than in the SCG group (5 genes). Functional analyses revealed that these genes are involved in diverse pathways, including DNA methylation, lignin biosynthesis, and cell differentiation. These findings suggested that the SCG and NCG groups have distinct demographic histories. Candidate genes identified are useful for future molecular breeding of cultivated ginseng. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Effect of radiographic contrast media on markers of complement activation and apoptosis in patients with chronic coronary artery disease undergoing coronary angiography.

PubMed

Deftereos, Spyridon; Giannopoulos, Georgios; Kossyvakis, Charalampos; Raisakis, Konstantinos; Kaoukis, Andreas; Driva, Metaxia; Ntzouvara, Olga; Panagopoulou, Vasiliki; Rentoukas, Ilias; Nikas, Dimitrios J; Pyrgakis, Vlasios; Alpert, Martin A

2009-09-01

The effects of radiographic contrast media on markers of complement activation and apoptosis in patients with chronic coronary artery disease (CAD) are unknown. The purpose of this study was to assess the comparative effects of ionic high-osmolar and non-ionic iso-osmolar radiographic contrast media on plasma markers of complement activation and apoptosis in patients with chronic CAD undergoing coronary angiography. Forty-four patients undergoing coronary angiography for chronic CAD were randomly assigned to receive the ionic high-osmolar radiographic contrast agent diatrizoate (Group A), or the non-ionic iso-osmolar contrast agent iodixanol (Group B) during angiography. Complement component 5 (C5a) and apoptotic markers sFas and sFasL were measured just prior to angiography and 1 hour after completion of angiography. Comparison of mean pre- and post-angiography plasma marker levels showed significantly greater increases in plasma levels in Group A than in Group B of C5a (29.30 +/- 5.45 ng/ml for Group A and 0.47 +/- 0.70 ng/ml for Group B (p < 0.00001), sFas (2.36 +/- 1.63 ng/ml for Group A and 0.23 +/- 0.90 ng/ml for Group B (p < 0.00001) and sFasL (14.00 +/- 5.41 pg/ml for Group A and 0.01 +/- 1.00 pg/ml for Group B (p < 0.00001). The results suggest that in patients with chronic CAD, the use of ionic high-osmolar radiographic contrast media during coronary angiography is associated with a more robust inflammatory and apoptotic milieu than that associated with the use of non-ionic iso-osmolar radiographic contrast media.

Genome-Wide Association Studies of Drug-Resistance Determinants.

PubMed

Volkman, Sarah K; Herman, Jonathan; Lukens, Amanda K; Hartl, Daniel L

2017-03-01

Population genetic strategies that leverage association, selection, and linkage have identified drug-resistant loci. However, challenges and limitations persist in identifying drug-resistance loci in malaria. In this review we discuss the genetic basis of drug resistance and the use of genome-wide association studies, complemented by selection and linkage studies, to identify and understand mechanisms of drug resistance and response. We also discuss the implications of nongenetic mechanisms of drug resistance recently reported in the literature, and present models of the interplay between nongenetic and genetic processes that contribute to the emergence of drug resistance. Throughout, we examine artemisinin resistance as an example to emphasize challenges in identifying phenotypes suitable for population genetic studies as well as complications due to multiple-factor drug resistance. Copyright © 2016. Published by Elsevier Ltd.

Systemic human CR2-targeted complement alternative pathway inhibitor ameliorates mouse laser-induced choroidal neovascularization.

PubMed

Rohrer, Bärbel; Coughlin, Beth; Bandyopadhyay, Mausumi; Holers, V Michael

2012-08-01

Genetic associations and the presence of complement components within pathological structures of age-related macular degeneration (AMD) have generated the hypothesis that AMD is caused by chronic local complement activation. Since the majority of activity in the common terminal pathway results from engagement of the amplification loop, the alternative pathway has been proposed as a logical therapeutic target. We recently generated a factor H (fH)-based complement inhibitor (CR2-fH) with the capacity to be "targeted" to sites of complement C3 activation. We asked whether the human therapeutic (TT30) is effective in a mouse model of AMD. Choroidal neovascularization (CNV) was induced by argon laser photocoagulation of Bruch's membrane. Every other day, mice received intravenous injections of TT30 or vehicles, and after 6 days, the presence or absence of CNV and CNV-related changes were evaluated. Area of CNV, photoreceptor cell function, gene expression for complement components and cytokines, vascular endothelial growth factor (VEGF) protein levels, and TT30 bioavailability were determined. CNV development, which has previously been shown to require local complement activation, could be reduced by intravenous TT30 delivery. Specific inhibition of the alternative pathway not only reduced angiogenesis in CNV, but also ameliorated changes in several associated disease-related biomarkers, including diminished retinal function and molecular events known to be involved in AMD such as VEGF production. After intravenous injection, TT30 localized to CNV lesion sites in the retinal pigmented epithelium-choroid. Systemic administration of TT30 was found to reduce CNV pathology. These data may open new avenues for novel systemic AMD treatment strategies.

A local complement response by RPE causes early-stage macular degeneration

PubMed Central

Fernandez-Godino, Rosario; Garland, Donita L.; Pierce, Eric A.

2015-01-01

Inherited and age-related macular degenerations (AMDs) are important causes of vision loss. An early hallmark of these disorders is the formation of sub-retinal pigment epithelium (RPE) basal deposits. A role for the complement system in MDs was suggested by genetic association studies, but direct functional connections between alterations in the complement system and the pathogenesis of MD remain to be defined. We used primary RPE cells from a mouse model of inherited MD due to a p.R345W mutation in EGF-containing fibulin-like extracellular matrix protein 1 (EFEMP1) to investigate the role of the RPE in early MD pathogenesis. Efemp1R345W RPE cells recapitulate the basal deposit formation observed in vivo by producing sub-RPE deposits in vitro. The deposits share features with basal deposits, and their formation was mediated by EFEMP1R345W or complement component 3a (C3a), but not by complement component 5a (C5a). Increased activation of complement appears to occur in response to an abnormal extracellular matrix (ECM), generated by the mutant EFEMP1R345W protein and reduced ECM turnover due to inhibition of matrix metalloproteinase 2 by EFEMP1R345W and C3a. Increased production of C3a also stimulated the release of cytokines such as interleukin (IL)-6 and IL-1B, which appear to have a role in deposit formation, albeit downstream of C3a. These studies provide the first direct indication that complement components produced locally by the RPE are involved in the formation of basal deposits. Furthermore, these results suggest that C3a generated by RPE is a potential therapeutic target for the treatment of EFEMP1-associated MD as well as AMD. PMID:26199322

Cobra venom factor immunoconjugates: effects of carbohydrate-directed versus amino group-directed conjugation.

PubMed

Zara, J; Pomato, N; McCabe, R P; Bredehorst, R; Vogel, C W

1995-01-01

Human IgM monoclonal antibody 16-88, derived from patients immunized with autologous colon carcinoma cells, was derivatized with two different cross-linkers, S-(2-thiopyridyl)-L-cysteine hydrazide (TPCH), which is carbohydrate-directed, and N-succinimidyl-3-(2- pyridyldithio)propionate (SPDP), which is amino group-directed. Two antibody functions, antigen binding and complement activation, were assayed upon derivatization with TPCH and SPDP. TPCH allowed for extensive modification (up to 17 TPCH molecules per antibody) without impairment of antigen binding activity, while this function was significantly compromised upon derivatization with SPDP. Antibody molecules derivatized with 16 SPDP residues showed almost complete loss of their antigen binding function. The complement activating ability of antibody 16-88 was significantly decreased after derivatization with TPCH or SPDP. In the case of SPDP derivatization, this decrease of the complement activating ability is predominantly a consequence of the impaired binding function. Upon conjugation of cobra venom factor (CVF), a nontoxic 137-kDa glycoprotein which is capable of activating the alternative pathway of complement, the antigen binding activity of SPDP-derivatized antibody was further compromised, whereas that of TPCH-derivatized antibody remained unaffected even after attachment of three or four CVF molecules per antibody. In both conjugates CVF retained good functional activity. CVF was slightly more active when attached to SPDP-derivatized antibody, suggesting a better accessibility of amino group-coupled CVF for its interaction with other complement proteins. These results indicate that carbohydrate-directed conjugation compromises the antibody function of complement activation, but allows for the generation of immunoconjugates with unimpaired antigen binding capability.(ABSTRACT TRUNCATED AT 250 WORDS)

Employability of genetic counselors with a PhD in genetic counseling.

PubMed

Wallace, Jody P; Myers, Melanie F; Huether, Carl A; Bedard, Angela C; Warren, Nancy Steinberg

2008-06-01

The development of a PhD in genetic counseling has been discussed for more than 20 years, yet the perspectives of employers have not been assessed. The goal of this qualitative study was to gain an understanding of the employability of genetic counselors with a PhD in genetic counseling by conducting interviews with United States employers of genetic counselors. Study participants were categorized according to one of the following practice areas: academic, clinical, government, industry, laboratory, or research. All participants were responsible for hiring genetic counselors in their institutions. Of the 30 employers interviewed, 23 envisioned opportunities for individuals with a PhD degree in genetic counseling, particularly in academic and research settings. Performing research and having the ability to be a principal investigator on a grant was the primary role envisioned for these individuals by 22/30 participants. Employers expect individuals with a PhD in genetic counseling to perform different roles than MS genetic counselors with a master's degree. This study suggests there is an employment niche for individuals who have a PhD in genetic counseling that complements, and does not compete with, master's prepared genetic counselors.

Genetic mouse models relevant to schizophrenia: taking stock and looking forward.

PubMed

Harrison, Paul J; Pritchett, David; Stumpenhorst, Katharina; Betts, Jill F; Nissen, Wiebke; Schweimer, Judith; Lane, Tracy; Burnet, Philip W J; Lamsa, Karri P; Sharp, Trevor; Bannerman, David M; Tunbridge, Elizabeth M

2012-03-01

Genetic mouse models relevant to schizophrenia complement, and have to a large extent supplanted, pharmacological and lesion-based rat models. The main attraction is that they potentially have greater construct validity; however, they share the fundamental limitations of all animal models of psychiatric disorder, and must also be viewed in the context of the uncertain and complex genetic architecture of psychosis. Some of the key issues, including the choice of gene to target, the manner of its manipulation, gene-gene and gene-environment interactions, and phenotypic characterization, are briefly considered in this commentary, illustrated by the relevant papers reported in this special issue. Copyright © 2011 Elsevier Ltd. All rights reserved.

Cryopreservation for preservation of potato genetic resources

PubMed Central

Niino, Takao; Arizaga, Miriam Valle

2015-01-01

Cryopreservation is becoming a very important tool for the long-term storage of plant genetic resources and efficient cryopreservation protocols have been developed for a large number of plant species. Practical procedures, developed using in vitro tissue culture, can be a simple and reliable preservation option of potato genetic resources rather than maintaining by vegetative propagation in genebanks due their allogamous nature. Cryopreserved materials insure a long-term backup of field collections against loss of plant germplasm. Occurrence of genetic variation, in tissue culture cells during prolonged subcultures, can be avoided with suitable cryopreservation protocols that provide high regrowth, leading and facilitating a systematic and strategic cryo-banking of plant genetic resources. Cryopreservation protocols for potato reviewed here, can efficiently complement field and in vitro conservation, providing for preservation of genotypes difficult to preserve by other methods, wild types and other species decided as priority collections. PMID:25931979

Update on hemolytic uremic syndrome: Diagnostic and therapeutic recommendations

PubMed Central

Salvadori, Maurizio; Bertoni, Elisabetta

2013-01-01

Hemolytic uremic syndrome (HUS) is a rare disease. In this work the authors review the recent findings on HUS, considering the different etiologic and pathogenetic classifications. New findings in genetics and, in particular, mutations of genes that encode the complement-regulatory proteins have improved our understanding of atypical HUS. Similarly, the complement proteins are clearly involved in all types of thrombotic microangiopathy: typical HUS, atypical HUS and thrombotic thrombocytopenic purpura (TTP). Furthermore, several secondary HUS appear to be related to abnormalities in complement genes in predisposed patients. The authors highlight the therapeutic aspects of this rare disease, examining both “traditional therapy” (including plasma therapy, kidney and kidney-liver transplantation) and “new therapies”. The latter include anti-Shiga-toxin antibodies and anti-C5 monoclonal antibody “eculizumab”. Eculizumab has been recently launched for the treatment of the atypical HUS, but it appears to be effective in the treatment of typical HUS and in TTP. Future therapies are in phases I and II. They include anti-C5 antibodies, which are more purified, less immunogenic and absorbed orally and, anti-C3 antibodies, which are more powerful, but potentially less safe. Additionally, infusions of recombinant complement-regulatory proteins are a potential future therapy. PMID:24255888

Chromosome-based genetic complementation system for Xylella fastidiosa.

PubMed

Matsumoto, Ayumi; Young, Glenn M; Igo, Michele M

2009-03-01

Xylella fastidiosa is a xylem-limited, gram-negative bacterium that causes Pierce's disease of grapevine. Here, we describe the construction of four vectors that facilitate the insertion of genes into a neutral site (NS1) in the X. fastidiosa chromosome. These vectors carry a colE1-like (pMB1) replicon and DNA sequences from NS1 flanking a multiple-cloning site and a resistance marker for one of the following antibiotics: chloramphenicol, erythromycin, gentamicin, or kanamycin. In X. fastidiosa, vectors with colE1-like (pMB1) replicons have been found to result primarily in the recovery of double recombinants rather than single recombinants. Thus, the ease of obtaining double recombinants and the stability of the resulting insertions at NS1 in the absence of selective pressure are the major advantages of this system. Based on in vitro and in planta characterizations, strains carrying insertions within NS1 are indistinguishable from wild-type X. fastidiosa in terms of growth rate, biofilm formation, and pathogenicity. To illustrate the usefulness of this system for complementation analysis, we constructed a strain carrying a mutation in the X. fastidiosa cpeB gene, which is predicted to encode a catalase/peroxidase, and showed that the sensitivity of this mutant to hydrogen peroxide could be overcome by the introduction of a wild-type copy of cpeB at NS1. Thus, this chromosome-based complementation system provides a valuable genetic tool for investigating the role of specific genes in X. fastidiosa cell physiology and virulence.

Genetic evidence for the essential role of PfNT1 in the transport and utilization of xanthine, guanine, guanosine and adenine by Plasmodium falciparum.

PubMed

El Bissati, Kamal; Downie, Megan J; Kim, Seong-Kyoun; Horowitz, Michael; Carter, Nicola; Ullman, Buddy; Ben Mamoun, Choukri

2008-10-01

The malaria parasite, Plasmodium falciparum, is unable to synthesize the purine ring de novo and is therefore wholly dependent upon purine salvage from the host for survival. Previous studies have indicated that a P. falciparum strain in which the purine transporter PfNT1 had been disrupted was unable to grow on physiological concentrations of adenosine, inosine and hypoxanthine. We have now used an episomally complemented pfnt1Delta knockout parasite strain to confirm genetically the functional role of PfNT1 in P. falciparum purine uptake and utilization. Episomal complementation by PfNT1 restored the ability of pfnt1Delta parasites to transport and utilize adenosine, inosine and hypoxanthine as purine sources. The ability of wild-type and pfnt1Delta knockout parasites to transport and utilize the other physiologically relevant purines adenine, guanine, guanosine and xanthine was also examined. Unlike wild-type and complemented P. falciparum parasites, pfnt1Delta parasites could not proliferate on guanine, guanosine or xanthine as purine sources, and no significant transport of these substrates could be detected in isolated parasites. Interestingly, whereas isolated pfnt1Delta parasites were still capable of adenine transport, these parasites grew only when adenine was provided at high, non-physiological concentrations. Taken together these results demonstrate that, in addition to hypoxanthine, inosine and adenosine, PfNT1 is essential for the transport and utilization of xanthine, guanine and guanosine.

Phenotypic characterization of ten methanol oxidation (Mox) mutant classes in methylobacterium AM1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nunn, D.N.; Lidstrom, M.E.

Twenty-five methanol oxidation mutants of the facultative methylotroph Methylobacterium strain AM1 have been characterized by complementation analysis and assigned to ten complementation groups, Mox A1,A2,A3 and B-H. We have characterized each of the mutants belonging to the ten Mox complementation groups by PMS-DCPIP dye linked methanol dehydrogenase activity, by methanol-dependent whole cell oxygen consumption, by the presence or absence of methanol dehydrogenase protein by SDS-polyacrylamide gels and Western blotting, by the absorption spectra of purified mutant methanol dehydrogenase proteins and by the presence or absence of the soluble cytochrome c proteins of Methylobacterium AM1. We propose functions for each ofmore » the genes deficient in the mutants of the ten Mox complementation groups. These functions include two linked genes that encode the methanol dehydrogenase structural protein and the soluble cytochrome c/sub L/, a gene encoding a secretion function essential for the synthesis and export of methanol dehydrogenase and cytochrome c/sub L/, three gene functions responsible for the proper association of the PQQ prosthetic group with the methanol dehydrogenase apoprotein and four positive regulatory gene functions controlling the expression of the ability to oxidize methanol. 24 refs., 5 figs., 2 tabs.« less

Research Results

NASA Astrophysics Data System (ADS)

2010-10-01

Relations found between human memories and similar neural patterns Double Star Program Received the IAA Laurels for Team Achievement Award Prof. Piao's Review Paper Published in Nature Arsenic Trioxide Controls the Fate of the PML-RARα Oncoprotein by Directly Binding PML Setdb2 restricts dorsal organizer territory and regulates left-right asymmetry through suppressing fgf8 activity Short-range scattering in quantum dots Single-molecule magnets may find their use in microelectronics β-Arrestin1 Regulates Zebrafish Hematopoiesis through Binding to YY1 and Relieving Polycomb Group Repression Studies shown gene present and absent complementation may contribute to the heterosis of maize Low frequency genetic variation may determine complex diseases Cation-π interaction playing vital roles in the regulation of integrin affinity, signaling, and biological functions Soybean diversity map may provide important basis for breeding Mutations related to Alzheimer's and rare skin disease

Novel and recently evolved miRNA clusters regulate expansive F-box gene networks through phasiRNAs in wild diploid strawberry

USDA-ARS?s Scientific Manuscript database

The wild strawberry, Fragaria vesca, has recently emerged as an excellent model for investigating flower and fruit traits in economically important fruit crops. Its history of physiological studies combined with sequenced genome and a full complement of molecular genetic tools facilitate investigat...

Initiation of a pan-genomic research project for Xylella fastidiosa

USDA-ARS?s Scientific Manuscript database

Differences in genomic structure and nucleotide polymorphism among strains form the genetic basis for adaptability of a bacterial species. This can be described by a bacterial pan-genome, which is defined as the full complement of genes in all strains of a species. The pan-genome is composed of a "c...

A deficiency of the homeotic complex of the beetle Tribolium

NASA Technical Reports Server (NTRS)

Stuart, J. J.; Brown, S. J.; Beeman, R. W.; Denell, R. E.; Spooner, B. S. (Principal Investigator)

1991-01-01

In Drosophila, the establishment of regional commitments along most of the anterior/posterior axis of the developing embryo depends on two clusters of homeotic genes: the Antennapedia complex (ANT-C) and the bithorax complex (BX-C). The red flour beetle has a single complex (HOM-C) representing the homologues of the ANT-C and BX-C in juxtaposition. Beetles trans-heterozygous for two particular HOM-C mutations spontaneously generate a large deficiency, presumably by an exchange within the common region of two overlapping inversions. Genetic and molecular results indicate that this deficiency spans at least the interval between the Deformed and abdominal-A homologues. In deficiency homozygous embryos, all gnathal, thoracic and abdominal segments develop antennal appendages, suggesting that a gene(s) has been deleted that acts to distinguish trunk from head. There is no evidence that beetles have a homologue of the segmentation gene fushi tarazu of similar genomic location and function. On the basis of the genetic tractability, convenient genome size and organization of Tribolium, and its relatively long phylogenetic divergence from Drosophila (>300 million years), we have integrated developmental genetic and molecular analyses of the HOM-C. We isolated about 70 mutations in the complex representing at least six complementation groups. The homeotic phenotypes of adults and lethal embryos lead us to believe that these beetle genes are homologous with the Drosophila genes indicated in Fig. 1 (see text).

A deficiency of the homeotic complex of the beetle Tribolium.

PubMed

Stuart, J J; Brown, S J; Beeman, R W; Denell, R E

1991-03-07

In Drosophila, the establishment of regional commitments along most of the anterior/posterior axis of the developing embryo depends on two clusters of homeotic genes: the Antennapedia complex (ANT-C) and the bithorax complex (BX-C). The red flour beetle has a single complex (HOM-C) representing the homologues of the ANT-C and BX-C in juxtaposition. Beetles trans-heterozygous for two particular HOM-C mutations spontaneously generate a large deficiency, presumably by an exchange within the common region of two overlapping inversions. Genetic and molecular results indicate that this deficiency spans at least the interval between the Deformed and abdominal-A homologues. In deficiency homozygous embryos, all gnathal, thoracic and abdominal segments develop antennal appendages, suggesting that a gene(s) has been deleted that acts to distinguish trunk from head. There is no evidence that beetles have a homologue of the segmentation gene fushi tarazu of similar genomic location and function. On the basis of the genetic tractability, convenient genome size and organization of Tribolium, and its relatively long phylogenetic divergence from Drosophila (>300 million years), we have integrated developmental genetic and molecular analyses of the HOM-C. We isolated about 70 mutations in the complex representing at least six complementation groups. The homeotic phenotypes of adults and lethal embryos lead us to believe that these beetle genes are homologous with the Drosophila genes indicated in Fig. 1 (see text).

Kikuchi-Fujimoto disease (histiocytic necrotizing lymphadenitis): report of a case with other autoimmune manifestations

PubMed Central

Merriman, Richard C.; Stone, Marvin J.

2007-01-01

Kikuchi-Fujimoto disease (KFD), or histiocytic necrotizing lymphadenitis, is a benign and self-limited disease that mainly affects young women. Patients present with localized lymphadenopathy, fever, and leukopenia in up to half of the cases. KFD can occur in association with systemic lupus erythematosus. We present the case of a patient with KFD and systemic lupus erythematosus, as well as relapsing polychondritis. This patient had persistently low C4 complement levels, so she was evaluated for a genetic defect in complement production and was found to have two “null” C4 alleles. We believe that this may have contributed to the development of her diseases. PMID:17431451

Complement C2 receptor inhibitor trispanning: from man to schistosome.

PubMed

Inal, Jameel M

2005-11-01

Horizontal gene transfer (HGT), in relation to genetic transfer between hosts and parasites, is a little described mechanism. Since the complement inhibitor CRIT was first discovered in the human Schistosoma parasite (the causative agent of Bilharzia) and in Trypanosoma cruzi (a parasite causing Chagas' disease), it has been found to be distributed amongst various species, ranging from the early teleost cod to rats and humans. In terms of evolutionary distance, as measured in a phylogenetic analysis of these CRIT genes at nucleotide level, the parasitic species are as removed from their human host as is the rat sequence, suggesting HGT. The hypotheses that CRIT in humans and schistosomes is orthologous and that the presence of CRIT in schistosomes occurs as a result of host-to-parasite HGT are presented in the light of empirical data and the growing body of data on mobile genetic elements in human and schistosome genomes. In summary, these data indicate phylogenetic proximity between Schistosoma and human CRIT, identity of function, high nucleotide/amino acid identity and secondary protein structure, as well as identical genomic organization.

The prognostic performance of the complement system in septic patients in emergency department: a cohort study.

PubMed

Zhao, Xin; Chen, Yun-Xia; Li, Chun-Sheng

2015-01-01

To investigate the prognostic performance of complement components in septic patients, complement 3, membrane attack complex (MAC) and mannose-binding lectin were measured and compared among adult patients with sepsis, severe sepsis and septic shock, as well as between in-hospital nonsurvivors and survivors. The prognostic value of complement components was compared with mortality in emergency department sepsis (MEDS) score. Median complement 3, MAC and mannose-binding lectin increased directly with the sepsis, severe sepsis and septic shock groups, and were significantly higher in nonsurvivors than in survivors. MEDS and MAC independently predicted in-hospital mortality. The prognostic performance of MAC was superior to MEDS as analyzed by receiver operating characteristic curve and area under the curve.

The Lectin Pathway of Complement and Rheumatic Heart Disease

PubMed Central

Beltrame, Marcia Holsbach; Catarino, Sandra Jeremias; Goeldner, Isabela; Boldt, Angelica Beate Winter; de Messias-Reason, Iara José

2014-01-01

The innate immune system is the first line of host defense against infection and is comprised of humoral and cellular mechanisms that recognize potential pathogens within minutes or hours of entry. The effector components of innate immunity include epithelial barriers, phagocytes, and natural killer cells, as well as cytokines and the complement system. Complement plays an important role in the immediate response against microorganisms, including Streptococcus sp. The lectin pathway is one of three pathways by which the complement system can be activated. This pathway is initiated by the binding of mannose-binding lectin (MBL), collectin 11 (CL-K1), and ficolins (Ficolin-1, Ficolin-2, and Ficolin-3) to microbial surface oligosaccharides and acetylated residues, respectively. Upon binding to target molecules, MBL, CL-K1, and ficolins form complexes with MBL-associated serine proteases 1 and 2 (MASP-1 and MASP-2), which cleave C4 and C2 forming the C3 convertase (C4b2a). Subsequent activation of complement cascade leads to opsonization, phagocytosis, and lysis of target microorganisms through the formation of the membrane-attack complex. In addition, activation of complement may induce several inflammatory effects, such as expression of adhesion molecules, chemotaxis and activation of leukocytes, release of reactive oxygen species, and secretion of cytokines and chemokines. In this chapter, we review the general aspects of the structure, function, and genetic polymorphism of lectin-pathway components and discuss most recent understanding on the role of the lectin pathway in the predisposition and clinical progression of Rheumatic Fever. PMID:25654073

The Fanconi anemia pathway requires FAA phosphorylation and FAA/FAC nuclear accumulation

PubMed Central

Yamashita, Takayuki; Kupfer, Gary M.; Naf, Dieter; Suliman, Ahmed; Joenje, Hans; Asano, Shigetaka; D’Andrea, Alan D.

1998-01-01

Fanconi anemia (FA) is an autosomal recessive cancer susceptibility syndrome with at least eight complementation groups (A–H). Two FA genes, corresponding to complementation groups A and C, have been cloned, but the function of the FAA and FAC proteins remains unknown. We have recently shown that the FAA and FAC proteins bind and form a nuclear complex. In the current study, we analyzed the FAA and FAC proteins in normal lymphoblasts and lymphoblasts from multiple FA complementation groups. In contrast to normal controls, FA cells derived from groups A, B, C, E, F, G, and H were defective in the formation of the FAA/FAC protein complex, the phosphorylation of the FAA protein, and the accumulation of the FAA/FAC protein complex in the nucleus. These biochemical events seem to define a signaling pathway required for the maintenance of genomic stability and normal hematopoiesis. Our results support the idea that multiple gene products cooperate in the FA Pathway. PMID:9789045

A stable shuttle vector system for efficient genetic complementation of Helicobacter pylori strains by transformation and conjugation.

PubMed

Heuermann, D; Haas, R

1998-03-01

A versatile plasmid shuttle vector system was constructed, which is useful for genetic complementation of Helicobacter pylori strains or mutants with cloned genes of homologous or heterologous origin. The individual plasmid vectors consist of the minimal essential genetic elements, including an origin of replication for Escherichia coli, a H. pylori-specific replicon originally identified on a small cryptic H. pylori plasmid, an oriT sequence and a multiple cloning site. Shuttle plasmid pHel2 carries a chloramphenicol resistance cassette (catGC) and pHel3 contains a kanamycin resistance gene (aphA-3) as the selectable marker; both are functional in E. coli and H. pylori. The shuttle plasmids were introduced into the H. pylori strain P1 by natural transformation. A efficiency of 7.0 x 10(-7) and 4.7 x 10(-7) transformants per viable recipient was achieved with pHel2 and pHel3, respectively, and both vectors showed stable, autonomous replication in H. pylori. An approximately 100-fold higher H. pylori transformation rate was obtained when the shuttle vectors for transformation were isolated from the homologous H. pylori strain, rather than E. coli, indicating that DNA restriction and modification mechanisms play a crucial role in plasmid transformation. Interestingly, both shuttle vectors could also be mobilized efficiently from E. coli into different H. pylori recipients, with pHel2 showing an efficiency of 2.0 x 10(-5) transconjugants per viable H. pylori P1 recipient. Thus, DNA restriction seems to be strongly reduced or absent during conjugal transfer. The functional complementation of a recA-deficient H. pylori mutant by the cloned H. pylori recA+ gene, and the expression of the heterologous green fluorescent protein (GFP) in H. pylori demonstrate the general usefulness of this system, which will significantly facilitate the molecular analysis of H. pylori virulence factors in the future.

Genetic interaction analysis of point mutations enables interrogation of gene function at a residue-level resolution

PubMed Central

Braberg, Hannes; Moehle, Erica A.; Shales, Michael; Guthrie, Christine; Krogan, Nevan J.

2014-01-01

We have achieved a residue-level resolution of genetic interaction mapping – a technique that measures how the function of one gene is affected by the alteration of a second gene – by analyzing point mutations. Here, we describe how to interpret point mutant genetic interactions, and outline key applications for the approach, including interrogation of protein interaction interfaces and active sites, and examination of post-translational modifications. Genetic interaction analysis has proven effective for characterizing cellular processes; however, to date, systematic high-throughput genetic interaction screens have relied on gene deletions or knockdowns, which limits the resolution of gene function analysis and poses problems for multifunctional genes. Our point mutant approach addresses these issues, and further provides a tool for in vivo structure-function analysis that complements traditional biophysical methods. We also discuss the potential for genetic interaction mapping of point mutations in human cells and its application to personalized medicine. PMID:24842270

C1 inhibitor-mediated myocardial protection from chronic intermittent hypoxia-induced injury

PubMed Central

Fu, Jinrong; Guo, Furong; Chen, Cheng; Yu, Xiaoman; Hu, Ke; Li, Mingjiang

2016-01-01

The optimal treatment for chronic intermittent hypoxia (CIH)-induced cardiovascular injuries has yet to be determined. The aim of the current study was to explore the potential protective effect and mechanism of a C1 inhibitor in CIH in the myocardium. The present study used a rat model of CIH in which complement regulatory protein, known as C1 inhibitor (C1INH), was administered to the rats in the intervention groups. Cardiomyocyte apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling. The expression of proteins associated with the apoptotic pathway, such as B-cell lymphoma 2 (Bcl-2), Bax and caspase-3 were detected by western blot analysis. The expression of complement C3 protein and RNA were also analyzed. C1INH was observed to improve the cardiac function in rats with CIH. Myocardial myeloperoxidase activity, a marker of neutrophil infiltration, was significantly decreased in the C1INH intervention group compared with the CIH control group, and cardiomyocyte apoptosis was significantly attenuated (P<0.05). Western blotting and reverse transcription-polymerase chain reaction analysis indicated that the protein expression levels of Bcl-2 were decreased and those of Bax were increased in the CIH group compared with the normal control group, but the protein expression levels of Bcl-2 were increased and those of Bax were decreased in the C1INH intervention group, as compared with the CIH group. Furthermore, the CIH-induced expression and synthesis of complement C3 in the myocardium were also reduced in the C1INH intervention group. C1INH, in addition to inhibiting complement activation and inflammation, preserved cardiac function in CIH-mediated myocardial cell injury through an anti-apoptotic mechanism. PMID:27698713

Complement inhibition in pre-clinical models of periodontitis and prospects for clinical application.

PubMed

Hajishengallis, George; Hajishengallis, Evlambia; Kajikawa, Tetsuhiro; Wang, Baomei; Yancopoulou, Despina; Ricklin, Daniel; Lambris, John D

2016-06-01

Periodontitis is a dysbiotic inflammatory disease leading to the destruction of the tooth-supporting tissues. Current therapies are not always effective and this prevalent oral disease continues to be a significant health and economic burden. Early clinical studies have associated periodontitis with elevated complement activity. Consistently, subsequent genetic and pharmacological studies in rodents have implicated the central complement component C3 and downstream signaling pathways in periodontal host-microbe interactions that promote dysbiosis and inflammatory bone loss. This review discusses these mechanistic advances and moreover focuses on the compstatin family of C3 inhibitors as a novel approach to treat periodontitis. In this regard, local application of the current lead analog Cp40 was recently shown to block both inducible and naturally occurring periodontitis in non-human primates. These promising results from non-human primate studies and the parallel development of Cp40 for clinical use highlight the feasibility for developing an adjunctive, C3-targeted therapy for human periodontitis. Copyright © 2016 Elsevier Ltd. All rights reserved.

Mycophenolate Mofetil in Combination with Steroids for Treatment of C3 Glomerulopathy: A Case Series.

PubMed

Avasare, Rupali S; Canetta, Pietro A; Bomback, Andrew S; Marasa, Maddalena; Caliskan, Yasar; Ozluk, Yasemin; Li, Yifu; Gharavi, Ali G; Appel, Gerald B

2018-03-07

C3 glomerulopathy is a form of complement-mediated GN. Immunosuppressive therapy may be beneficial in the treatment of C3 glomerulopathy. Mycophenolate mofetil is an attractive treatment option given its role in the treatment of other complement-mediated diseases and the results of the Spanish Group for the Study of Glomerular Diseases C3 Study. Here, we study the outcomes of patients with C3 glomerulopathy treated with steroids and mycophenolate mofetil. We conducted a retrospective chart review of patients in the C3 glomerulopathy registry at Columbia University and identified patients treated with mycophenolate mofetil for at least 3 months and follow-up for at least 1 year. We studied clinical, histologic, and genetic data for the whole group and compared data for those who achieved complete or partial remission (responders) with those who did not achieve remission (nonresponders). We compared remission with mycophenolate mofetil with remission with other immunosuppressive regimens. We identified 30 patients who met inclusion criteria. Median age was 25 years old (interquartile range, 18-36), median creatinine was 1.07 mg/dl (interquartile range, 0.79-1.69), and median proteinuria was 3200 mg/g creatinine (interquartile range, 1720-6759). The median follow-up time was 32 months (interquartile range, 21-68). Twenty (67%) patients were classified as responders. There were no significant differences in baseline characteristics between responders and nonresponders, although initial proteinuria was lower (median 2468 mg/g creatinine) in responders compared with nonresponders (median 5000 mg/g creatinine) and soluble membrane attack complex levels were higher in responders compared with nonresponders. For those tapered off mycophenolate mofetil, relapse rate was 50%. Genome-wide analysis on complement genes was done, and in 12 patients, we found 18 variants predicted to be damaging. None of these variants were previously reported to be pathogenic. Mycophenolate mofetil with steroids outperformed other immunosuppressive regimens. Among patients who tolerated mycophenolate mofetil, combination therapy with steroids induced remission in 67% of this cohort. Heavier proteinuria at the start of therapy and lower soluble membrane attack complex levels were associated with treatment resistance. Copyright © 2018 by the American Society of Nephrology.

Isolation and Characterization of Chromosome-Gain and Increase-in-Ploidy Mutants in Yeast

PubMed Central

Chan, CSM.; Botstein, D.

1993-01-01

We have developed a colony papillation assay for monitoring the copy number of genetically marked chromosomes II and III in Saccharomyces cerevisiae. The unique feature of this assay is that it allows detection of a gain of the marked chromosomes even if there is a gain of the entire set of chromosomes (increase-in-ploidy). This assay was used to screen for chromosome-gain or increase-in-ploidy mutants. Five complementation groups have been defined for recessive mutations that confer an increase-in-ploidy (ipl) phenotype, which, in each case, cosegregates with a temperature-sensitive growth phenotype. Four new alleles of CDC31, which is required for spindle pole body duplication, were also recovered from this screen. Temperature-shift experiments with ipl1 cells show that they suffer severe nondisjunction at 37°. Similar experiments with ipl2 cells show that they gain entire sets of chromosomes and become arrested as unbudded cells at 37°. Molecular cloning and genetic mapping show that IPL1 is a newly identified gene, whereas IPL2 is allelic to BEM2, which is required for normal bud growth. PMID:8293973

Identification of four novel XPC mutations in two xeroderma pigmentosum complementation group C patients and functional study of XPC Q320X mutant.

PubMed

Gu, Yajuan; Chang, Xiaodan; Dai, Shan; Song, Qinghua; Zhao, Hongshan; Lei, Pengcheng

2017-09-10

Xeroderma pigmentosum (XP) is a rare, recessive hereditary disease characterized by sunlight hypersensitivity and high incidence of skin cancer with clinical and genetic heterogeneity. We collected two unrelated Chinese patients showing typical symptoms of XPC without neurologic symptoms. Direct sequencing of XPC gene revealed that patient 1 carried IVS1+1G>A and c.958 C>T mutations, and patient 2 carried c.545_546delTA and c.2257_2258insC mutations. All these four mutations introduced premature terminal codons (PTCs) in XPC gene. The nonsense mutation c.958 C>T yielded truncated mutant Q320X, and we studied its function for global genome repair kinetics. Overexpressed Q320X mutant can localize to site of DNA damage, but it is defective in CPD and 6-4PP repair. Readthrough of PTCs is a new approach to treatment of genetic diseases. We found that aminoglycosides could significantly increase the full length protein expression of Q320X mutant, but NER defects were not rescued in vitro. Copyright © 2017 Elsevier B.V. All rights reserved.

Malfunction of nuclease ERCC1-XPF results in diverse clinical manifestations and causes Cockayne syndrome, xeroderma pigmentosum, and Fanconi anemia.

PubMed

Kashiyama, Kazuya; Nakazawa, Yuka; Pilz, Daniela T; Guo, Chaowan; Shimada, Mayuko; Sasaki, Kensaku; Fawcett, Heather; Wing, Jonathan F; Lewin, Susan O; Carr, Lucinda; Li, Tao-Sheng; Yoshiura, Koh-ichiro; Utani, Atsushi; Hirano, Akiyoshi; Yamashita, Shunichi; Greenblatt, Danielle; Nardo, Tiziana; Stefanini, Miria; McGibbon, David; Sarkany, Robert; Fassihi, Hiva; Takahashi, Yoshito; Nagayama, Yuji; Mitsutake, Norisato; Lehmann, Alan R; Ogi, Tomoo

2013-05-02

Cockayne syndrome (CS) is a genetic disorder characterized by developmental abnormalities and photodermatosis resulting from the lack of transcription-coupled nucleotide excision repair, which is responsible for the removal of photodamage from actively transcribed genes. To date, all identified causative mutations for CS have been in the two known CS-associated genes, ERCC8 (CSA) and ERCC6 (CSB). For the rare combined xeroderma pigmentosum (XP) and CS phenotype, all identified mutations are in three of the XP-associated genes, ERCC3 (XPB), ERCC2 (XPD), and ERCC5 (XPG). In a previous report, we identified several CS cases who did not have mutations in any of these genes. In this paper, we describe three CS individuals deficient in ERCC1 or ERCC4 (XPF). Remarkably, one of these individuals with XP complementation group F (XP-F) had clinical features of three different DNA-repair disorders--CS, XP, and Fanconi anemia (FA). Our results, together with those from Bogliolo et al., who describe XPF alterations resulting in FA alone, indicate a multifunctional role for XPF. Copyright © 2013 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

Accelerating global optimization of aerodynamic shapes using a new surrogate-assisted parallel genetic algorithm

NASA Astrophysics Data System (ADS)

Ebrahimi, Mehdi; Jahangirian, Alireza

2017-12-01

An efficient strategy is presented for global shape optimization of wing sections with a parallel genetic algorithm. Several computational techniques are applied to increase the convergence rate and the efficiency of the method. A variable fidelity computational evaluation method is applied in which the expensive Navier-Stokes flow solver is complemented by an inexpensive multi-layer perceptron neural network for the objective function evaluations. A population dispersion method that consists of two phases, of exploration and refinement, is developed to improve the convergence rate and the robustness of the genetic algorithm. Owing to the nature of the optimization problem, a parallel framework based on the master/slave approach is used. The outcomes indicate that the method is able to find the global optimum with significantly lower computational time in comparison to the conventional genetic algorithm.

Influence of ethnic traditional cultures on genetic diversity of rice landraces under on-farm conservation in southwest China.

PubMed

Wang, Yanjie; Wang, Yanli; Sun, Xiaodong; Caiji, Zhuoma; Yang, Jingbiao; Cui, Di; Cao, Guilan; Ma, Xiaoding; Han, Bing; Xue, Dayuan; Han, Longzhi

2016-10-27

Crop genetic resources are important components of biodiversity. However, with the large-scale promotion of mono-cropping, genetic diversity has largely been lost. Ex-situ conservation approaches were widely used to protect traditional crop varieties worldwide. However, this method fails to maintain the dynamic evolutionary processes of crop genetic resources in their original habitats, leading to genetic diversity reduction and even loss of the capacity of resistance to new diseases and pests. Therefore, on-farm conservation has been considered a crucial complement to ex-situ conservation. This study aimed at clarifying the genetic diversity differences between ex-situ conservation and on-farm conservation and to exploring the influence of traditional cultures on genetic diversity of rice landraces under on-farm conservation. The conservation status of rice landrace varieties, including Indica and Japonica, non-glutinous rice (Oryza sativa) and glutinous rice (Oryza sativa var. glutinosa Matsum), was obtained through ethno-biology investigation method in 12 villages of ethnic groups from Guizhou, Yunnan and Guangxi provinces of China. The genetic diversity between 24 pairs of the same rice landraces from different times were compared using simple sequence repeat (SSR) molecular markers technology. The landrace paris studied were collected in 1980 and maintained ex-situ, while 2014 samples were collected on-farm in southwest of China. The results showed that many varieties of rice landraces have been preserved on-farm by local farmers for hundreds or thousands of years. The number of alleles (Na), effective number of alleles (Ne), Nei genetic diversity index (He) and Shannon information index (I) of rice landraces were significantly higher by 12.3-30.4 % under on-farm conservation than under ex-situ conservation. Compared with the ex-situ conservation approach, rice landraces under on-farm conservation programs had more alleles and higher genetic diversity. In every site we investigated, ethnic traditional cultures play a positive influence on rice landrace variety diversity and genetic diversity. Most China's rice landraces were conserved in the ethnic areas of southwest China. On-farm conservation can effectively promote the allelic variation and increase the genetic diversity of rice landraces over the past 35 years. Moreover, ethnic traditional culture practices are a crucial foundation to increase genetic diversity of rice landraces and implement on-farm conservation.

The Group B Streptococcus-Secreted Protein CIP Interacts with C4, Preventing C3b Deposition via the Lectin and Classical Complement Pathways.

PubMed

Pietrocola, Giampiero; Rindi, Simonetta; Rosini, Roberto; Buccato, Scilla; Speziale, Pietro; Margarit, Immaculada

2016-01-01

The group B Streptococcus (GBS) is a leading cause of neonatal invasive disease. GBS bacteria are surrounded by a thick capsular polysaccharide that is a potent inhibitor of complement deposition via the alternative pathway. Several of its surface molecules can however activate the classical and lectin complement pathways, rendering this species still vulnerable to phagocytic killing. In this study we have identified a novel secreted protein named complement interfering protein (CIP) that downregulates complement activation via the classical and lectin pathways, but not the alternative pathway. The CIP protein showed high affinity toward C4b and inhibited its interaction with C2, presumably preventing the formation of the C4bC2a convertase. Addition of recombinant CIP to GBS cip-negative bacteria resulted in decreased deposition of C3b on their surface and in diminished phagocytic killing in a whole-blood assay. Our data reveal a novel strategy exploited by GBS to counteract innate immunity and could be valuable for the development of anti-infective agents against this important pathogen. Copyright © 2015 by The American Association of Immunologists, Inc.

Complementation of DNA repair defect in xeroderma pigmentosum cells of group C by the transfer of human chromosome 5

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kaur, G.P.; Athwal, R.S.

1993-01-01

Complementation of DNA excision repair defect in xeroderma pigmentosum cells of group C (XP-C) has been achieved by the transfer of human chromosome 5. Individual human chromosomes tagged with a selectable marker were transferred to XP-C cells by microcell fusion from mouse-human hybrid cell lines each bearing a single different human chromosome. Analysis of the chromosome transfer clones revealed that introduction of chromosome 5 into XP-C cells corrected the DNA repair defect as well as UV-sensitive phenotypes, while chromosomes 2, 6, 7, 9, 13, 15, 17, and 21 failed to complement. The introduced chromosome 5 in complemented UV[sup r] clonesmore » was distinguished from the parental XP-C chromosomes by polymorphism for dinucleotide (CA)[sub n] repeats at two loci, D5S117 and D5S209. In addition, an intact marked chromosome 5 was rescued into mouse cells from a complemented UV[sup r] clone by microcell fusion. Five subclones of a complemented clone that had lost the marked chromosome 5 exhibited UV-sensitive and repair-deficient phenotypes identical to parental XP-C cells. Concordant loss of the transferred chromosome and reappearance of XP-C phenotype further confirmed the presence of a DNA repair gene on human chromosome 5. 38 refs., 7 figs., 1 tab.« less

Complement mutations in diacylglycerol kinase-ε-associated atypical hemolytic uremic syndrome.

PubMed

Sánchez Chinchilla, Daniel; Pinto, Sheila; Hoppe, Bernd; Adragna, Marta; Lopez, Laura; Justa Roldan, Maria Luisa; Peña, Antonia; Lopez Trascasa, Margarita; Sánchez-Corral, Pilar; Rodríguez de Córdoba, Santiago

2014-09-05

Atypical hemolytic uremic syndrome is characterized by vascular endothelial damage caused by complement dysregulation. Consistently, complement inhibition therapies are highly effective in most patients with atypical hemolytic uremic syndrome. Recently, it was shown that a significant percentage of patients with early-onset atypical hemolytic uremic syndrome carry mutations in diacylglycerol kinase-ε, an intracellular protein with no obvious role in complement. These data support an alternative, complement-independent mechanism leading to thrombotic microangiopathy that has implications for treatment of early-onset atypical hemolytic uremic syndrome. To get additional insights into this new form of atypical hemolytic uremic syndrome, the diacylglycerol kinase-ε gene in a cohort with atypical hemolytic uremic syndrome was analyzed. Eighty-three patients with early-onset atypical hemolytic uremic syndrome (<2 years) enrolled in the Spanish atypical hemolytic uremic syndrome registry between 1999 and 2013 were screened for mutations in diacylglycerol kinase-ε. These patients were also fully characterized for mutations in the genes encoding factor H, membrane cofactor protein, factor I, C3, factor B, and thrombomodulin CFHRs copy number variations and rearrangements, and antifactor H antibodies. Four patients carried mutations in diacylglycerol kinase-ε, one p.H536Qfs*16 homozygote and three compound heterozygotes (p.W322*/p.P498R, two patients; p.Q248H/p.G484Gfs*10, one patient). Three patients also carried heterozygous mutations in thrombomodulin or C3. Extensive plasma infusions controlled atypical hemolytic uremic syndrome recurrences and prevented renal failure in the two patients with diacylglycerol kinase-ε and thrombomodulin mutations. A positive response to plasma infusions and complement inhibition treatment was also observed in the patient with concurrent diacylglycerol kinase-ε and C3 mutations. Data suggest that complement dysregulation influences the onset and disease severity in carriers of diacylglycerol kinase-ε mutations and that treatments on the basis of plasma infusions and complement inhibition are potentially useful in patients with combined diacylglycerol kinase-ε and complement mutations. A comprehensive understanding of the genetic component predisposing to atypical hemolytic uremic syndrome is, therefore, critical to guide an effective treatment. Copyright © 2014 by the American Society of Nephrology.

Complement Mutations in Diacylglycerol Kinase-ε–Associated Atypical Hemolytic Uremic Syndrome

PubMed Central

Sánchez Chinchilla, Daniel; Pinto, Sheila; Hoppe, Bernd; Adragna, Marta; Lopez, Laura; Justa Roldan, Maria Luisa; Peña, Antonia; Lopez Trascasa, Margarita; Sánchez-Corral, Pilar; Rodríguez de Córdoba, Santiago

2014-01-01

Background and objectives Atypical hemolytic uremic syndrome is characterized by vascular endothelial damage caused by complement dysregulation. Consistently, complement inhibition therapies are highly effective in most patients with atypical hemolytic uremic syndrome. Recently, it was shown that a significant percentage of patients with early-onset atypical hemolytic uremic syndrome carry mutations in diacylglycerol kinase-ε, an intracellular protein with no obvious role in complement. These data support an alternative, complement-independent mechanism leading to thrombotic microangiopathy that has implications for treatment of early-onset atypical hemolytic uremic syndrome. To get additional insights into this new form of atypical hemolytic uremic syndrome, the diacylglycerol kinase-ε gene in a cohort with atypical hemolytic uremic syndrome was analyzed. Design, setting, participants, & measurements Eighty-three patients with early-onset atypical hemolytic uremic syndrome (<2 years) enrolled in the Spanish atypical hemolytic uremic syndrome registry between 1999 and 2013 were screened for mutations in diacylglycerol kinase-ε. These patients were also fully characterized for mutations in the genes encoding factor H, membrane cofactor protein, factor I, C3, factor B, and thrombomodulin CFHRs copy number variations and rearrangements, and antifactor H antibodies. Results Four patients carried mutations in diacylglycerol kinase-ε, one p.H536Qfs*16 homozygote and three compound heterozygotes (p.W322*/p.P498R, two patients; p.Q248H/p.G484Gfs*10, one patient). Three patients also carried heterozygous mutations in thrombomodulin or C3. Extensive plasma infusions controlled atypical hemolytic uremic syndrome recurrences and prevented renal failure in the two patients with diacylglycerol kinase-ε and thrombomodulin mutations. A positive response to plasma infusions and complement inhibition treatment was also observed in the patient with concurrent diacylglycerol kinase-ε and C3 mutations. Conclusions Data suggest that complement dysregulation influences the onset and disease severity in carriers of diacylglycerol kinase-ε mutations and that treatments on the basis of plasma infusions and complement inhibition are potentially useful in patients with combined diacylglycerol kinase-ε and complement mutations. A comprehensive understanding of the genetic component predisposing to atypical hemolytic uremic syndrome is, therefore, critical to guide an effective treatment. PMID:25135762

A second-generation blood substitute (perfluorodichlorooctane emulsion) does not activate complement during an ex vivo circulation model of bypass.

PubMed

Rosoff, J D; Soltow, L O; Vocelka, C R; Schmer, G; Chandler, W L; Cochran, R P; Kunzelman, K S; Spiess, B D

1998-08-01

To examine whether a second-generation perfluorocarbon (PFC) blood substitute added to the cardiopulmonary bypass (CPB) prime influences complement production. A prospective, randomized, single-blinded, ex vivo model. A university hospital, laboratory, and clinics. Ten healthy adult consented volunteer blood donors (five men, five women). Ex vivo closed-loop extracorporeal circuit including membrane oxygenator, tubing, and filter primed with crystalloid or crystalloid plus PFC was circulated for 1 hour with the addition of 500 mL of heparinized fresh human whole blood. Laboratory specimens were drawn from the circuit at 10-minute intervals for 1 hour and measured for complement (C3a, Bb fragment) concentrations, blood gases, fibrinogen concentration, platelet count, and hematocrit. In the PFC group, C3a and Bb fragments were equal to or less than those in the group that received crystalloid alone. The second-generation PFC added to the prime of a CPB circuit does not independently increase complement production.

Proteomic analysis in peritoneal dialysis patients with different peritoneal transport characteristics.

PubMed

Wen, Qiong; Zhang, Li; Mao, Hai-Ping; Tang, Xue-Qing; Rong, Rong; Fan, Jin-Jin; Yu, Xue-Qing

2013-08-30

Peritoneal membranes can be categorized as high, high average, low average, and low transporters, based on the removal or transport rate of solutes. In this study, we used proteomic analysis to determine the differences in proteins removed by different types of peritoneal membranes. Peritoneal transport characteristics in patients who received peritoneal dialysis therapy were assessed by a peritoneal equilibration test. Two-dimensional differential gel electrophoresis technology followed by quantitative analysis was performed to study the variation in protein expression from peritoneal dialysis effluents (PDE) among different groups. Proteins were identified by MALDI-TOF-MS/MS analyses. Further validation in PDE or serum was performed utilizing ELISA analysis. Proteomics analysis revealed ten protein spots with significant differences in intensity levels among different groups, including vitamin D-binding protein, complement C3, apolipoprotein-A1, complement factor C4A, haptoglobin, alpha-1 antitrypsin, immunoglobulin kappa light chain, alpha-2-microglobulin, retinol-binding protein 4 and transthyretin. The levels of vitamin D-binding protein, complement C3, and apolipoprotein-A1 in PDE derived from different groups were greatly varied (P<0.05). However, no significant difference was found in the serum levels of these proteins among different groups (P>0.05 for all groups). This study provides a novel overview of the differences in PDE proteomes of four types of peritoneal membranes. Vitamin D-binding protein, complement C3, and apolipoprotein-A1 showed enhanced expression in PDE of patients with high transporter. Copyright © 2013 Elsevier Inc. All rights reserved.

Emerging from the bottleneck: Benefits of the comparative approach to modern neuroscience

PubMed Central

Brenowitz, Eliot A.; Zakon, Harold H.

2015-01-01

Neuroscience historically exploited a wide diversity of animal taxa. Recently, however, research focused increasingly on a few model species. This trend accelerated with the genetic revolution, as genomic sequences and genetic tools became available for a few species, which formed a bottleneck. This coalescence on a small set of model species comes with several costs often not considered, especially in the current drive to use mice explicitly as models for human diseases. Comparative studies of strategically chosen non-model species can complement model species research and yield more rigorous studies. As genetic sequences and tools become available for many more species, we are poised to emerge from the bottleneck and once again exploit the rich biological diversity offered by comparative studies. PMID:25800324

European Union funded project on the development of a whole complement deficiency screening ELISA-A story of success and an exceptional manager: Mohamed R. Daha.

PubMed

Würzner, Reinhard; Tedesco, Francesco; Garred, Peter; Mollnes, Tom Eirik; Truedsson, Lennart; Turner, Malcolm W; Sommarin, Yngve; Wieslander, Jörgen; Sim, Robert B

2015-11-01

A whole complement ELISA-based assay kit, primarily designed to screen for deficiencies in components of the complement system was developed during a European Union grant involving more than a dozen European scientists and a small-medium enterprise company (Wieslab, which later merged into Eurodiagnostica). The consortium was led by Prof. Mohamed R. Daha who had already guided a preceding European grant which prepared the ground for this endeavor to create a novel and sophisticated complement measurement tool. The final result of the grant was a scientific publication (Seelen et al., 2005, J. Immunol. Methods 296, 187-198) and a commercially available complement deficiency screening kit, WIESLAB(®) Complement system Screen. Thereafter, the group decided to carry on with a grant, located at Innsbruck Medical University, and supported by royalties and unrestricted educational grants from Eurodiagnostica, Malmö, entitled "Search for Applications for WIESLAB(®) Complement system Screen (SAW)" with the aim to look for further applications of this assay. During the latter project the group organized several scientific meetings aimed at evaluating the use of the assay as well as developing further branches of its platform. A look back over almost two decades reveals a great story of excellent research which was also commercially successful, fulfilling the aims of European Union grants. It is also a story of ageless friendship, only possible due to the vision and guidance of an exceptional manager: Moh Daha. Copyright © 2015 Elsevier Ltd. All rights reserved.

Centromeres of filamentous fungi.

PubMed

Smith, Kristina M; Galazka, Jonathan M; Phatale, Pallavi A; Connolly, Lanelle R; Freitag, Michael

2012-07-01

How centromeres are assembled and maintained remains one of the fundamental questions in cell biology. Over the past 20 years, the idea of centromeres as precise genetic loci has been replaced by the realization that it is predominantly the protein complement that defines centromere localization and function. Thus, placement and maintenance of centromeres are excellent examples of epigenetic phenomena in the strict sense. In contrast, the highly derived "point centromeres" of the budding yeast Saccharomyces cerevisiae and its close relatives are counter-examples for this general principle of centromere maintenance. While we have learned much in the past decade, it remains unclear if mechanisms for epigenetic centromere placement and maintenance are shared among various groups of organisms. For that reason, it seems prudent to examine species from many different phylogenetic groups with the aim to extract comparative information that will yield a more complete picture of cell division in all eukaryotes. This review addresses what has been learned by studying the centromeres of filamentous fungi, a large, heterogeneous group of organisms that includes important plant, animal and human pathogens, saprobes, and symbionts that fulfill essential roles in the biosphere, as well as a growing number of taxa that have become indispensable for industrial use.

Centromeres of filamentous fungi

PubMed Central

Smith, Kristina M.; Galazka, Jonathan M.; Phatale, Pallavi A.; Connolly, Lanelle R.; Freitag, Michael

2012-01-01

How centromeres are assembled and maintained remains one of the fundamental questions in cell biology. Over the past 20 years the idea of centromeres as precise genetic loci has been replaced by the realization that it is predominantly the protein complement that defines centromere localization and function. Thus, placement and maintenance of centromeres are excellent examples of epigenetic phenomena in the strict sense. In contrast, the highly derived “point centromeres” of the budding yeast Saccharomyces cerevisiae and its close relatives are counterexamples for this general principle of centromere maintenance. While we have learned much in the past decade, it remains unclear if mechanisms for epigenetic centromere placement and maintenance are shared amongst various groups of organisms. For that reason it seems prudent to examine species from many different phylogenetic groups with the aim to extract comparative information that will yield a more complete picture of cell division in all eukaryotes. This review addresses what has been learned by studying the centromeres of filamentous fungi, a large, heterogeneous group of organisms that includes important plant, animal and human pathogens, saprobes and symbionts that fulfill essential roles in the biosphere, as well as a growing number of taxa that have become indispensable for industrial use. PMID:22752455

Functional Analysis of Variants of Unknown Significance in BRCA1 and BRCA2 Using Complementation of a Synthetic Lethal Interaction with PARP Inhibition

DTIC Science & Technology

2014-12-01

general population3-5. A pathogenic mutation in BRCA1 or BRCA2 is an important genetic biomarker for a high ovarian cancer risk in breast cancer patients...doxycycline induces cytological signs of synthetic lethality with Parp inhibitor by RAD51 and RH2AX focus formation. REPORTABLE OUTCOMES None RH2AX... genetics . Mar 2001;68(3):700-710. 3. Chen S, Parmigiani G. Meta-analysis of BRCA1 and BRCA2 penetrance. Journal of clinical oncology : official journal of

Emai Sentence Complements in Typological Perspective.

ERIC Educational Resources Information Center

Schaefer, Ronald P.; Egbokhare, Francis O.

This paper explores the syntactic and semantic character of previously undescribed sentence complements (SCs) in Emai, a Benue-Congo language of Nigeria's Edoid group. Data come from ongoing documentation incorporating oral narrative texts as well as dictionary and grammar descriptions. To delineate the grammatical properties of SCs, the paper…

Mutations participating in interallelic complementation in propionic acidemia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gravel, R.A.; Akerman, B.R.; Lamhonwah, A.M.

1994-07-01

Deficiency of propionyl-CoA carboxylase (PCC; [alpha][sub 4][beta][sub 4]) results in the rare, autosomal recessive disease propionic acidemia. Cell fusion experiments have revealed two complementation groups, pccA and pccB, corresponding to defects of the PCCA ([alpha]-subunit) and PCCB ([beta]-subunit) genes, respectively. The pccBCC group includes subgroups, pccB and pccC, which are thought to reflect interallelic complementation between certain mutations of the PCCB gene. In this study, the authors have identified the mutations in two pccB, one pccC, and two pccBC cell lines and have deduced those alleles participating in interallelic complementation. One pccB line was a compound hetrozygote of Pro228Leu andmore » Asn536Asp. The latter mutation was also detected in a noncomplementing pccBC line. This leaves Pro228Leu responsible for complementation in the pccB cells. The second pccB line contained an insertional duplication, dupKICK140-143, and a splice mutation IVS+1 G[yields]T, located after Lys466. The authors suggest that the dupKICK mutation is the complementing allele, since the second allele is incompatible with normal splicing. The pccC line studied was homozygous for Arg410Trp, which is necessarily the complementing allele in that line. For a second pccC line, they previously had proposed that [Delta]Ile408 was the complementing allele. They now show that its second allele, [open quotes]Ins[center dot]Del[close quotes], a 14-bp deletion replaced by a 12-bp insertion beginning at codon 407, fails to complement in homozygous form. The authors conclude that the interallelic complementation results from mutations in domains that can interact between [beta]-subunits in the PCC heteromer to restore enzymatic function. On the basis of sequence homology with the Propionibacterium shermanii transcarboxylase 12S subunit, they suggest that the pccC domain, defined by Ile408 and Arg410, may involve the propionyl-CoA binding site. 37 refs., 5 figs., 2 tabs.« less

Complement System in Dermatological Diseases – Fire Under the Skin

PubMed Central

Panelius, Jaana; Meri, Seppo

2015-01-01

The complement system plays a key role in several dermatological diseases. Overactivation, deficiency, or abnormality of the control proteins are often related to a skin disease. Autoimmune mechanisms with autoantibodies and a cytotoxic effect of the complement membrane attack complex on epidermal or vascular cells can cause direct tissue damage and inflammation, e.g., in systemic lupus erythematosus (SLE), phospholipid antibody syndrome, and bullous skin diseases like pemphigoid. By evading complement attack, some microbes like Borrelia spirochetes and staphylococci can persist in the skin and cause prolonged symptoms. In this review, we present the most important skin diseases connected to abnormalities in the function of the complement system. Drugs having an effect on the complement system are also briefly described. On one hand, drugs with free hydroxyl on amino groups (e.g., hydralazine, procainamide) could interact with C4A, C4B, or C3 and cause an SLE-like disease. On the other hand, progress in studies on complement has led to novel anti-complement drugs (recombinant C1-inhibitor and anti-C5 antibody, eculizumab) that could alleviate symptoms in diseases associated with excessive complement activation. The main theme of the manuscript is to show how relevant the complement system is as an immune effector system in contributing to tissue injury and inflammation in a broad range of skin disorders. PMID:25688346

Complement and the control of HIV infection: an evolving story.

PubMed

Frank, Michael M; Hester, Christopher; Jiang, Haixiang

2014-05-01

Thirty years ago, investigators isolated and later determined the structure of HIV-1 and its envelope proteins. Using techniques that were effective with other viruses, they prepared vaccines designed to generate antibody or T-cell responses, but they were ineffective in clinical trials. In this article, we consider the role of complement in host defense against enveloped viruses, the role it might play in the antibody response and why complement has not controlled HIV-1 infection. Complement consists of a large group of cell-bound and plasma proteins that are an integral part of the innate immune system. They provide a first line of defense against microbes and also play a role in the immune response. Here we review the studies of complement-mediated HIV destruction and the role of complement in the HIV antibody response. HIV-1 has evolved a complex defense to prevent complement-mediated killing reviewed here. As part of these studies, we have discovered that HIV-1 envelope, on administration into animals, is rapidly broken down into small peptides that may prove to be very inefficient at provident the type of antigenic stimulation that leads to an effective immune response. Improving complement binding and stabilizing envelope may improve the vaccine response.

On the Functional Overlap between Complement and Anti-Microbial Peptides.

PubMed

Zimmer, Jana; Hobkirk, James; Mohamed, Fatima; Browning, Michael J; Stover, Cordula M

2014-01-01

Intriguingly, activated complement and anti-microbial peptides share certain functionalities; lytic, phagocytic, and chemo-attractant activities and each may, in addition, exert cell instructive roles. Each has been shown to have distinct LPS detoxifying activity and may play a role in the development of endotoxin tolerance. In search of the origin of complement, a functional homolog of complement C3 involved in opsonization has been identified in horseshoe crabs. Horseshoe crabs possess anti-microbial peptides able to bind to acyl chains or phosphate groups/saccharides of endotoxin, LPS. Complement activity as a whole is detectable in marine invertebrates. These are also a source of anti-microbial peptides with potential pharmaceutical applicability. Investigating the locality for the production of complement pathway proteins and their role in modulating cellular immune responses are emerging fields. The significance of local synthesis of complement components is becoming clearer from in vivo studies of parenchymatous disease involving specifically generated, complement-deficient mouse lines. Complement C3 is a central component of complement activation. Its provision by cells of the myeloid lineage varies. Their effector functions in turn are increased in the presence of anti-microbial peptides. This may point to a potentiating range of activities, which should serve the maintenance of health but may also cause disease. Because of the therapeutic implications, this review will consider closely studies dealing with complement activation and anti-microbial peptide activity in acute inflammation (e.g., dialysis-related peritonitis, appendicitis, and ischemia).

IMMUNOLOGIC AND PHYSIOLOGIC OBSERVATIONS IN BABOONS WITH LIFE-SUPPORTING GENETICALLY-ENGINEERED PIG KIDNEY GRAFTS

PubMed Central

Iwase, Hayato; Hara, Hidetaka; Ezzelarab, Mohamed; Li, Tao; Zhang, Zhongqiang; Gao, Bingsi; Liu, Hong; Long, Cassandra; Wang, Yi; Cassano, Amy; Klein, Edwin; Phelps, Carol; Ayares, David; Humar, Abhinav; Wijkstrom, Martin; Cooper, David KC

2017-01-01

Background Genetically-engineered pigs could provide a source of kidneys for clinical transplantation. The two longest kidney graft survivals reported to date have been 136 days and 310 days, but graft survival >30 days has been unusual until recently. Methods Donor pigs (n=4) were on an α1,3-galactosyltransferase gene-knockout (GTKO)/human complement-regulatory protein (CD46) background (GTKO/CD46). In addition, the pigs were transgenic for at least one human coagulation-regulatory protein. Two baboons received a kidney from a 6-gene pig (Group A) and two from a 3-gene pig (Group B). Immunosuppressive therapy was identical in all 4 cases, and consisted of anti-thymoglobulin (ATG) + anti-CD20mAb (induction) and anti-CD40mAb + rapamycin + corticosteroids (maintenance). Anti-TNF-α and anti-IL-6R mAbs were administered to reduce the inflammatory response. Baboons were followed by clinical/laboratory monitoring of immune/coagulation/inflammatory/physiological parameters. At biopsy or euthanasia, the grafts were examined by microscopy. Results The two Group A baboons remained healthy with normal renal function >7 and >8 months, respectively, but then developed infectious complications. However, no features of a consumptive coagulopathy, e.g., thrombocytopenia, reduction of fibrinogen, or of a protein-losing nephropathy were observed. There was no evidence of an elicited anti-pig antibody response, and histology of biopsies taken at approximately 4, 6, and 7 months and at necropsy showed no significant abnormalities. In contrast, both Group B baboons developed features of a consumptive coagulopathy and required euthanasia on day 12. Conclusions The combination of (i) a graft from a specific 6-gene genetically-modified pig, (ii) an effective immunosuppressive regimen, and (iii) anti-inflammatory therapy prevented immune injury, a protein-losing nephropathy, and coagulation dysfunction for >7 months. Although the number of experiments is very limited, our impression is that expression of human endothelial protein C receptor (+/− CD55) in the graft is important if coagulation dysregulation is to be avoided. PMID:28303661

Immunological and physiological observations in baboons with life-supporting genetically engineered pig kidney grafts.

PubMed

Iwase, Hayato; Hara, Hidetaka; Ezzelarab, Mohamed; Li, Tao; Zhang, Zhongqiang; Gao, Bingsi; Liu, Hong; Long, Cassandra; Wang, Yi; Cassano, Amy; Klein, Edwin; Phelps, Carol; Ayares, David; Humar, Abhinav; Wijkstrom, Martin; Cooper, David K C

2017-03-01

Genetically engineered pigs could provide a source of kidneys for clinical transplantation. The two longest kidney graft survivals reported to date have been 136 and 310 days, but graft survival >30 days has been unusual until recently. Donor pigs (n=4) were on an α1,3-galactosyltransferase gene-knockout (GTKO)/human complement regulatory protein (CD46) background (GTKO/CD46). In addition, the pigs were transgenic for at least one human coagulation regulatory protein. Two baboons received a kidney from a six-gene pig (GroupA) and two from a three-gene pig (GroupB). Immunosuppressive therapy was identical in all four cases and consisted of anti-thymoglobulin (ATG)+anti-CD20mAb (induction) and anti-CD40mAb+rapamycin+corticosteroids (maintenance). Anti-TNF-α and anti-IL-6R mAbs were administered to reduce the inflammatory response. Baboons were followed by clinical/laboratory monitoring of immune/coagulation/inflammatory/physiological parameters. At biopsy or euthanasia, the grafts were examined by microscopy. The two GroupA baboons remained healthy with normal renal function >7 and >8 months, respectively, but then developed infectious complications. However, no features of a consumptive coagulopathy, eg, thrombocytopenia and reduction of fibrinogen, or of a protein-losing nephropathy were observed. There was no evidence of an elicited anti-pig antibody response, and histology of biopsies taken at approximately 4, 6, and 7 months and at necropsy showed no significant abnormalities. In contrast, both GroupB baboons developed features of a consumptive coagulopathy and required euthanasia on day 12. The combination of (i) a graft from a specific six-gene genetically modified pig, (ii) an effective immunosuppressive regimen, and (iii) anti-inflammatory therapy prevented immune injury, a protein-losing nephropathy, and coagulation dysfunction for >7 months. Although the number of experiments is very limited, our impression is that expression of human endothelial protein C receptor (±CD55) in the graft is important if coagulation dysregulation is to be avoided. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Xeroderma pigmentosum complementation group F: Report of a case and review of Japanese patients.

PubMed

Tofuku, Yukari; Nobeyama, Yoshimasa; Kamide, Ryoichi; Moriwaki, Shinichi; Nakagawa, Hidemi

2015-09-01

Xeroderma pigmentosum (XP) is an autosomal recessive genetic disorder characterized by extraordinary sensitivity to sunlight, resulting in cutaneous malignant tumors. Among XP, XP-F presents relatively uniquely in Japanese. To clarify the characteristics of this group, we describe a case of XP-F and review Japanese cases previously reported. A 50-year-old Japanese woman was referred to us with multiple, variously sized, light- or dark-brown macules on the face and sunlight-exposed extremities. She had experienced bulla formation with approximately 10 min of sunlight exposure during her elementary school years. Her parents had been first cousins, and her mother and sister had photosensitivity. She showed no neurological or developmental abnormalities. Ultraviolet (UV) irradiation testing revealed normal levels for minimal erythema dose with UV-A and UV-B. Sensitivity to UV-C and DNA repair ability in the patient's fibroblasts were indicated between that in normal individuals and that in an XP-A patient. Complementation assay revealed that transfection of the XPF gene led most efficient DNA repair compared with the other XP genes. Therefore, the patient was diagnosed with XP-F. Twenty-three cases of Japanese patients (six males, 17 females) with XP-F have been reported, including the present case. Our review suggested a relatively high prevalence of 50% (11/22) for cutaneous malignant tumors. A significant difference was evident in the mean age at first medical consultation between patients with cutaneous malignant tumors (53.6 years) and patients without such tumors (30.8 years). This suggests that cutaneous malignant tumors could occur in the age range of 30-50 years in XP-F patients. © 2015 Japanese Dermatological Association.

Complementation of hypersensitivity to DNA interstrand crosslinking agents demonstrates that XRCC2 is a Fanconi anaemia gene.

PubMed

Park, Jung-Young; Virts, Elizabeth L; Jankowska, Anna; Wiek, Constanze; Othman, Mohamed; Chakraborty, Sujata C; Vance, Gail H; Alkuraya, Fowzan S; Hanenberg, Helmut; Andreassen, Paul R

2016-10-01

Fanconi anaemia (FA) is a heterogeneous inherited disorder clinically characterised by progressive bone marrow failure, congenital anomalies and a predisposition to malignancies. Determine, based on correction of cellular phenotypes, whether XRCC2 is a FA gene. Cells (900677A) from a previously identified patient with biallelic mutation of XRCC2, among other mutations, were genetically complemented with wild-type XRCC2. Wild-type XRCC2 corrects each of three phenotypes characteristic of FA cells, all related to the repair of DNA interstrand crosslinks, including increased sensitivity to mitomycin C (MMC), chromosome breakage and G2-M accumulation in the cell cycle. Further, the p.R215X mutant of XRCC2, which is harboured by the patient, is unstable. This provides an explanation for the pathogenesis of this mutant, as does the fact that 900677A cells have reduced levels of other proteins in the XRCC2-RAD51B-C-D complex. Also, FANCD2 monoubiquitination and foci formation, but not assembly of RAD51 foci, are normal in 900677A cells. Thus, XRCC2 acts late in the FA-BRCA pathway as also suggested by hypersensitivity of 900677A cells to ionising radiation. These cells also share milder sensitivities towards olaparib and formaldehyde with certain other FA cells. XRCC2/FANCU is a FA gene, as is another RAD51 paralog gene, RAD51C/FANCO. Notably, similar to a subset of FA genes that act downstream of FANCD2, biallelic mutation of XRCC2/FANCU has not been associated with bone marrow failure. Taken together, our results yield important insights into phenotypes related to FA and its genetic origins. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Complement component 5 contributes to poor disease outcome in humans and mice with pneumococcal meningitis

PubMed Central

Woehrl, Bianca; Brouwer, Matthijs C.; Murr, Carmen; Heckenberg, Sebastiaan G.B.; Baas, Frank; Pfister, Hans W.; Zwinderman, Aeilko H.; Morgan, B. Paul; Barnum, Scott R.; van der Ende, Arie; Koedel, Uwe; van de Beek, Diederik

2011-01-01

Pneumococcal meningitis is the most common and severe form of bacterial meningitis. Fatality rates are substantial, and long-term sequelae develop in about half of survivors. Disease outcome has been related to the severity of the proinflammatory response in the subarachnoid space. The complement system, which mediates key inflammatory processes, has been implicated as a modulator of pneumococcal meningitis disease severity in animal studies. Additionally, SNPs in genes encoding complement pathway proteins have been linked to susceptibility to pneumococcal infection, although no associations with disease severity or outcome have been established. Here, we have performed a robust prospective nationwide genetic association study in patients with bacterial meningitis and found that a common nonsynonymous complement component 5 (C5) SNP (rs17611) is associated with unfavorable disease outcome. C5 fragment levels in cerebrospinal fluid (CSF) of patients with bacterial meningitis correlated with several clinical indicators of poor prognosis. Consistent with these human data, C5a receptor–deficient mice with pneumococcal meningitis had lower CSF wbc counts and decreased brain damage compared with WT mice. Adjuvant treatment with C5-specific monoclonal antibodies prevented death in all mice with pneumococcal meningitis. Thus, our results suggest C5-specific monoclonal antibodies could be a promising new antiinflammatory adjuvant therapy for pneumococcal meningitis. PMID:21926466

Molecular replication

NASA Technical Reports Server (NTRS)

Orgel, L. E.

1986-01-01

The object of our research program is to understand how polynucleotide replication originated on the primitive Earth. This is a central issue in studies of the origins of life, since a process similar to modern DNA and RNA synthesis is likely to have formed the basis for the most primitive system of genetic information transfer. The major conclusion of studies so far is that a preformed polynucleotide template under many different experimental conditions will facilitate the synthesis of a new oligonucleotide with a sequence complementary to that of the template. It has been shown, for example, that poly(C) facilitates the synthesis of long oligo(G)s and that the short template CCGCC facilities the synthesis of its complement GGCGG. Very recently we have shown that template-directed synthesis is not limited to the standard oligonucleotide substrates. Nucleic acid-like molecules with a pyrophosphate group replacing the phosphate of the standard nucleic acid backbone are readily synthesized from deoxynucleotide 3'-5'-diphosphates on appropriate templates.

Microfibrillar associated protein 4 mfap4 genes in catfish play a novel role in innate immune responses

USDA-ARS?s Scientific Manuscript database

The lectin pathway of the complement system is characterized by two groups of soluble pattern recognition molecules, mannose-binding lectins (MBLs) and ficolins. These molecules recognize and bind carbohydrates in pathogens and activate complement leading to opsonization, leukocyte activation, and d...

A TALE of shrimps: Genome-wide survey of homeobox genes in 120 species from diverse crustacean taxa.

PubMed

Chang, Wai Hoong; Lai, Alvina G

2018-01-01

The homeodomain-containing proteins are an important group of transcription factors found in most eukaryotes including animals, plants and fungi. Homeobox genes are responsible for a wide range of critical developmental and physiological processes, ranging from embryonic development, innate immune homeostasis to whole-body regeneration. With continued fascination on this key class of proteins by developmental and evolutionary biologists, multiple efforts have thus far focused on the identification and characterization of homeobox orthologs from key model organisms in attempts to infer their evolutionary origin and how this underpins the evolution of complex body plans. Despite their importance, the genetic complement of homeobox genes has yet been described in one of the most valuable groups of animals representing economically important food crops. With crustacean aquaculture being a growing industry worldwide, it is clear that systematic and cross-species identification of crustacean homeobox orthologs is necessary in order to harness this genetic circuitry for the improvement of aquaculture sustainability. Using publicly available transcriptome data sets, we identified a total of 4183 putative homeobox genes from 120 crustacean species that include food crop species, such as lobsters, shrimps, crayfish and crabs. Additionally, we identified 717 homeobox orthologs from 6 other non-crustacean arthropods, which include the scorpion, deer tick, mosquitoes and centipede. This high confidence set of homeobox genes will now serve as a key resource to the broader community for future functional and comparative genomics studies.

Low serum immunglobulin G (IgG) during nephrosis is a predictor of urinary tract infection (UTI) in children with nephrotic syndrome.

PubMed

Afroz, S; Roy, D K; Khan, A H

2013-04-01

Low serum level of IgG, complement C3 and C4 in nephrotic syndrome children may cause increased susceptibility to infection. Serum level of IgG and complements in nephrotic children (NS) with UTI has been analyzed in this cross sectional study. It was carried out in the department of Pediatric nephrology, National Institute of Kidney Diseases & Urology (NIKDU), Dhaka, Bangladesh. The study subjects were followed up prospectively for one year to see and compare the frequency of relapse of NS and UTI. Patients were selected in a nonrandom purposive technique. Nephrotic syndrome children with initial attack between 1-12 year of age were included over a period of one year. The patients were grouped into Group I - UTI positive and Group II - UTI negative depending on urine culture positivity and colony count >10⁵ CFU/ml. Serum IgG and complements C3, C4 levels were done in both groups during nephrosis and were compared. A total of 101 children M: F 1.7:1, mean age 5.96±3.2 years were included in this study. Group I, n=45 vs. Group II, n=56. The mean serum level of IgG was low in Group I (549.91±210.71 vs. 728.64±235.81mg/dl, p<0.001). Serum IgG level less than 700mg/dl was found in 37 vs. 23 children {x² (¹) 17.52 p<0.001, OR=6.63}. Mean serum complement C3 level was also low in Group I (123.09±40.52 vs. 143.38±37.06mg/dl, p<0.05). But complement C3 and C4 level do not carry any risk of developing UTI in nephrotic children. Higher number of children in Group II were at remission (n=24) during follow up, while frequent relapsers were high in Group I (n=22). Increased frequency of UTI attack (88 episodes) was found in Group I children compared to none in Group II during follow up. So low serum level of IgG in children with NS during nephrosis can predict UTI with an odds ratio of 6.63 as well as relapse. Serum level of C3, C4 do not associated with any risk of development of UTI in NS children.

Structure-function analysis of rotavirus NSP2 octamer by using a novel complementation system.

PubMed

Taraporewala, Zenobia F; Jiang, Xiaofang; Vasquez-Del Carpio, Rodrigo; Jayaram, Hariharan; Prasad, B V Venkataram; Patton, John T

2006-08-01

Viral inclusion bodies, or viroplasms, that form in rotavirus-infected cells direct replication and packaging of the segmented double-stranded RNA (dsRNA) genome. NSP2, one of two rotavirus proteins needed for viroplasm assembly, possesses NTPase, RNA-binding, and helix-unwinding activities. NSP2 of the rotavirus group causing endemic infantile diarrhea (group A) was shown to self-assemble into large doughnut-shaped octamers with circumferential grooves and deep clefts containing nucleotide-binding histidine triad (HIT)-like motifs. Here, we demonstrate that NSP2 of group C rotavirus, a group that fails to reassort with group A viruses, retains the unique architecture of the group A octamer but differs in surface charge distribution. By using an NSP2-dependent complementation system, we show that the HIT-dependent NTPase activity of NSP2 is necessary for dsRNA synthesis, but not for viroplasm formation. The complementation system also showed that despite the retention of the octamer structure and the HIT-like fold, group C NSP2 failed to rescue replication and viroplasm formation in NSP2-deficient cells infected with group A rotavirus. The distinct differences in the surface charges on the Bristol and SA11 NSP2 octamers suggest that charge complementarity of the viroplasm-forming proteins guides the specificity of viroplasm formation and, possibly, reassortment restriction between rotavirus groups.

In vitro immunomodulatory activity of plants used by the Tacana ethnic group in Bolivia.

PubMed

Deharo, E; Baelmans, R; Gimenez, A; Quenevo, C; Bourdy, G

2004-09-01

One hundred and seventy-eight ethanolic plant extracts from the pharmacopoeia of the Tacana, an ethnic group from Bolivia, were screened for immunomodulatory activity using complement cascade inhibition and ADP-induced platelet aggregation inhibition assays. Six impaired both complement pathways (classical and alternative): stem bark from Astronium urundeuvea (Anacardiaceae), Cochlospermum vitifolium (Cochlospermaceae), Terminalia amazonica (Combretaceae), Triplaris americana (Polygonaceae), Uncaria tomentosa (Rubiaceae) and Euterpe precatoria (Arecaceae) roots. Inhibition of complement cascade was independent of essential ion complexation, and was not due to direct hemolytic activity on target red blood cells. For A. urundeuvea, C. vitifolium, and T. amazonica, anti-inflammatory activity relied on cyclo-oxygenase inhibition. Four of these species (A. urundeuva, T. americana, U. tomentosa and E. precatoria) are used traditionally to treat inflammatory processes.

Plasmids for increased efficiency of vector construction and genetic engineering in filamentous fungi.

PubMed

Schoberle, Taylor J; Nguyen-Coleman, C Kim; May, Gregory S

2013-01-01

Fungal species are continuously being studied to not only understand disease in humans and plants but also to identify novel antibiotics and other metabolites of industrial importance. Genetic manipulations, such as gene deletion, gene complementation, and gene over-expression, are common techniques to investigate fungal gene functions. Although advances in transformation efficiency and promoter usage have improved genetic studies, some basic steps in vector construction are still laborious and time-consuming. Gateway cloning technology solves this problem by increasing the efficiency of vector construction through the use of λ phage integrase proteins and att recombination sites. We developed a series of Gateway-compatible vectors for use in genetic studies in a range of fungal species. They contain nutritional and drug-resistance markers and can be utilized to manipulate different filamentous fungal genomes. Copyright © 2013 Elsevier Inc. All rights reserved.

Golden Rice and 'Golden' crops for human nutrition.

PubMed

Beyer, Peter

2010-11-30

Micronutrients are essential for a healthy life. Humans do not produce micronutrients, and hence they must obtain them through the foodchain. Staple crops are the predominant food source of mankind, but need to be complemented by other foodstuffs because they are generally deficient in one or the other micronutrient. Breeding for micronutrient-dense crops is not always a viable option because of the absence of genetic variability for the desired trait. Moreover, sterility issues and the complex genetic makeup of some crop plants make them unamenable to conventional breeding. In these cases, genetic modification remains the only viable option. The tools to produce a number of micronutrients in staple crops have recently become available thanks to the identification of the genes involved in the corresponding biochemical pathways at an unprecedented rate. Discarding genetic modification as a viable option is definitely not in the interest of human wellbeing. Copyright © 2010 Elsevier B.V. All rights reserved.

Application of Genetic/Genomic Approaches to Allergic Disorders

PubMed Central

Baye, Tesfaye M.; Martin, Lisa J.; Khurana Hershey, Gurjit K.

2010-01-01

Completion of the human genome project and rapid progress in genetics and bioinformatics have enabled the development of large public databases, which include genetic and genomic data linked to clinical health data. With the massive amount of information available, clinicians and researchers have the unique opportunity to complement and integrate their daily practice with the existing resources to clarify the underlying etiology of complex phenotypes such as allergic diseases. The genome itself is now often utilized as a starting point for many studies and multiple innovative approaches have emerged applying genetic/genomic strategies to key questions in the field of allergy and immunology. There have been several successes, which have uncovered new insights into the biologic underpinnings of allergic disorders. Herein, we will provide an in depth review of genomic approaches to identifying genes and biologic networks involved in allergic diseases. We will discuss genetic and phenotypic variation, statistical approaches for gene discovery, public databases, functional genomics, clinical implications, and the challenges that remain. PMID:20638111

Current Progress of Genetically Engineered Pig Models for Biomedical Research

PubMed Central

Gün, Gökhan

2014-01-01

Abstract The first transgenic pigs were generated for agricultural purposes about three decades ago. Since then, the micromanipulation techniques of pig oocytes and embryos expanded from pronuclear injection of foreign DNA to somatic cell nuclear transfer, intracytoplasmic sperm injection-mediated gene transfer, lentiviral transduction, and cytoplasmic injection. Mechanistically, the passive transgenesis approach based on random integration of foreign DNA was developed to active genetic engineering techniques based on the transient activity of ectopic enzymes, such as transposases, recombinases, and programmable nucleases. Whole-genome sequencing and annotation of advanced genome maps of the pig complemented these developments. The full implementation of these tools promises to immensely increase the efficiency and, in parallel, to reduce the costs for the generation of genetically engineered pigs. Today, the major application of genetically engineered pigs is found in the field of biomedical disease modeling. It is anticipated that genetically engineered pigs will increasingly be used in biomedical research, since this model shows several similarities to humans with regard to physiology, metabolism, genome organization, pathology, and aging. PMID:25469311

Mouse-human experimental epigenetic analysis unmasks dietary targets and genetic liability for diabetic phenotypes

PubMed Central

Multhaup, Michael L.; Seldin, Marcus; Jaffe, Andrew E.; Lei, Xia; Kirchner, Henriette; Mondal, Prosenjit; Li, Yuanyuan; Rodriguez, Varenka; Drong, Alexander; Hussain, Mehboob; Lindgren, Cecilia; McCarthy, Mark; Näslund, Erik; Zierath, Juleen R.; Wong, G. William; Feinberg, Andrew P.

2015-01-01

SUMMARY Using a functional approach to investigate the epigenetics of Type 2 Diabetes (T2D), we combine three lines of evidence – diet-induced epigenetic dysregulation in mouse, epigenetic conservation in humans, and T2D clinical risk evidence – to identify genes implicated in T2D pathogenesis through epigenetic mechanisms related to obesity. Beginning with dietary manipulation of genetically homogeneous mice, we identify differentially DNA-methylated genomic regions. We then replicate these results in adipose samples from lean and obese patients pre- and post-Roux-en-Y gastric bypass, identifying regions where both the location and direction of methylation change is conserved. These regions overlap with 27 genetic T2D risk loci, only one of which was deemed significant by GWAS alone. Functional analysis of genes associated with these regions revealed four genes with roles in insulin resistance, demonstrating the potential general utility of this approach for complementing conventional human genetic studies by integrating cross-species epigenomics and clinical genetic risk. PMID:25565211

Null EPAC Mutants Reveal a Sequential Order of Versatile cAMP Effects during "Drosophila" Aversive Odor Learning

ERIC Educational Resources Information Center

Richlitzki, Antje; Latour, Philipp; Schwärzel, Martin

2017-01-01

Here, we define a role of the cAMP intermediate EPAC in "Drosophila" aversive odor learning by means of null epac mutants. Complementation analysis revealed that EPAC acts downstream from the "rutabaga" adenylyl cyclase and in parallel to protein kinase A. By means of targeted knockdown and genetic rescue we identified mushroom…

Analysis of single nucleotide polymorphisms in case-control studies.

PubMed

Li, Yonghong; Shiffman, Dov; Oberbauer, Rainer

2011-01-01

Single nucleotide polymorphisms (SNPs) are the most common type of genetic variants in the human genome. SNPs are known to modify susceptibility to complex diseases. We describe and discuss methods used to identify SNPs associated with disease in case-control studies. An outline on study population selection, sample collection and genotyping platforms is presented, complemented by SNP selection, data preprocessing and analysis.

Lupus erythematosus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tuffanelli, D.L.

1981-02-01

Lupus erythematosus (LE) is a multisystem disease. Genetic predisposition, altered immunity, hormones, drugs, viruses, and ultraviolet light all may play a role in etiology. A wide range of cutaneous lesions occur, and variants such as subacute cutaneous LE, complement-deficient LE, and neonatal LE have recently been emphasized. Management of the LE patient, including appropriate diagnostic studies and therapy relevant to the dermatologist, is discussed in the review.

Dense Deposit Disease

PubMed Central

Smith, Richard J.H; Harris, Claire L.; Pickering, Matthew C.

2011-01-01

Dense deposit disease (DDD) is an orphan disease that primarily affects children and young adults without sexual predilection. Studies of its pathophysiology have shown conclusively that it is caused by fluid-phase dysregulation of the alternative pathway of complement, however the role played by genetics and autoantibodies like C3 nephritic factors must be more thoroughly defined if we are to make an impact in the clinical management of this disease. There are currently no mechanism-directed therapies to offer affected patients, half of whom progress to end stage renal failure disease within 10 years of diagnosis. Transplant recipients face the dim prospect of disease recurrence in their allografts, half of which ultimately fail. More detailed genetic and complement studies of DDD patients may make it possible to identify protective factors prognostic for naïve kidney and transplant survival, or conversely risk factors associated with progression to renal failure and allograft loss. The pathophysiology of DDD suggests that a number of different treatments warrant consideration. As advances are made in these areas, there will be a need to increase healthcare provider awareness of DDD by making resources available to clinicians to optimize care for DDD patients. PMID:21601923

Medicago truncatula CYP716A12 Is a Multifunctional Oxidase Involved in the Biosynthesis of Hemolytic Saponins[W

PubMed Central

Carelli, Maria; Biazzi, Elisa; Panara, Francesco; Tava, Aldo; Scaramelli, Laura; Porceddu, Andrea; Graham, Neil; Odoardi, Miriam; Piano, Efisio; Arcioni, Sergio; May, Sean; Scotti, Carla; Calderini, Ornella

2011-01-01

Saponins, a group of glycosidic compounds present in several plant species, have aglycone moieties that are formed using triterpenoid or steroidal skeletons. In spite of their importance as antimicrobial compounds and their possible benefits for human health, knowledge of the genetic control of saponin biosynthesis is still poorly understood. In the Medicago genus, the hemolytic activity of saponins is related to the nature of their aglycone moieties. We have identified a cytochrome P450 gene (CYP716A12) involved in saponin synthesis in Medicago truncatula using a combined genetic and biochemical approach. Genetic loss-of-function analysis and complementation studies showed that CYP716A12 is responsible for an early step in the saponin biosynthetic pathway. Mutants in CYP716A12 were unable to produce hemolytic saponins and only synthetized soyasaponins, and were thus named lacking hemolytic activity (lha). In vitro enzymatic activity assays indicate that CYP716A12 catalyzes the oxidation of β-amyrin and erythrodiol at the C-28 position, yielding oleanolic acid. Transcriptome changes in the lha mutant showed a modulation in the main steps of triterpenic saponin biosynthetic pathway: squalene cyclization, β-amyrin oxidation, and glycosylation. The analysis of CYP716A12 expression in planta is reported together with the sapogenin content in different tissues and stages. This article provides evidence for CYP716A12 being a key gene in hemolytic saponin biosynthesis. PMID:21821776

How rare bone diseases have informed our knowledge of complex diseases.

PubMed

Johnson, Mark L

2016-01-01

Rare bone diseases, generally defined as monogenic traits with either autosomal recessive or dominant patterns of inheritance, have provided a rich database of genes and associated pathways over the past 2-3 decades. The molecular genetic dissection of these bone diseases has yielded some major surprises in terms of the causal genes and/or involved pathways. The discovery of genes/pathways involved in diseases such as osteopetrosis, osteosclerosis, osteogenesis imperfecta and many other rare bone diseases have all accelerated our understanding of complex traits. Importantly these discoveries have provided either direct validation for a specific gene embedded in a group of genes within an interval identified through a complex trait genome-wide association study (GWAS) or based upon the pathway associated with a monogenic trait gene, provided a means to prioritize a large number of genes for functional validation studies. In some instances GWAS studies have yielded candidate genes that fall within linkage intervals associated with monogenic traits and resulted in the identification of causal mutations in those rare diseases. Driving all of this discovery is a complement of technologies such as genome sequencing, bioinformatics and advanced statistical analysis methods that have accelerated genetic dissection and greatly reduced the cost. Thus, rare bone disorders in partnership with GWAS have brought us to the brink of a new era of personalized genomic medicine in which the prevention and management of complex diseases will be driven by the molecular understanding of each individuals contributing genetic risks for disease.

shl, a New set of Arabidopsis mutants with exaggerated developmental responses to available red, far-red, and blue light.

PubMed

Pepper, A E; Seong-Kim, M; Hebst, S M; Ivey, K N; Kwak, S J; Broyles, D E

2001-09-01

The interaction of light perception with development is the subject of intensive genetic analysis in the model plant Arabidopsis. We performed genetic screens in low white light-a threshold condition in which photomorphogenetic signaling pathways are only partially active-for ethyl methane sulfonate-generated mutants with altered developmental phenotypes. Recessive mutants with exaggerated developmental responses were obtained in eight complementation groups designated shl for seedlings hyperresponsive to light. shl1, shl2, shl5, and shl3 shl4 (double mutant) seedlings showed limited or no phenotypic effects in darkness, but showed significantly enhanced inhibition of hypocotyl elongation in low-white, red, far-red, blue, and green light across a range of fluences. These results reflect developmental hyper-responsiveness to signals generated by both phytochrome and cryptochrome photoreceptors. The shl11 mutant retained significant phenotypic effects on hypocotyl length in both the phyA mutant and phyB mutant backgrounds but may be dependent on CRY1 for phenotypic expression in blue light. The shl2 phenotype was partially dependent on PHYB, PHYA, and CRY1 in red, far-red, and blue light, respectively. shl2 and, in particular, shl1 were partially dependent on HY5 activity for their light-hyperresponsive phenotypes. The SHL genes act (genetically) as light-dependent negative regulators of photomorphogenesis, possibly in a downstream signaling or developmental pathway that is shared by CRY1, PHYA, and PHYB and other photoreceptors (CRY2, PHYC, PHYD, and PHYE).

Potential influences of complement factor H in autoimmune inflammatory and thrombotic disorders.

PubMed

Ferluga, Janez; Kouser, Lubna; Murugaiah, Valarmathy; Sim, Robert B; Kishore, Uday

2017-04-01

Complement system homeostasis is important for host self-protection and anti-microbial immune surveillance, and recent research indicates roles in tissue development and remodelling. Complement also appears to have several points of interaction with the blood coagulation system. Deficiency and altered function due to gene mutations and polymorphisms in complement effectors and regulators, including Factor H, have been associated with familial and sporadic autoimmune inflammatory - thrombotic disorders, in which autoantibodies play a part. These include systemic lupus erythematosus, rheumatoid arthritis, atypical haemolytic uremic syndrome, anti-phospholipid syndrome and age-related macular degeneration. Such diseases are generally complex - multigenic and heterogeneous in their symptoms and predisposition/susceptibility. They usually need to be triggered by vascular trauma, drugs or infection and non-complement genetic factors also play a part. Underlying events seem to include decline in peripheral regulatory T cells, dendritic cell, and B cell tolerance, associated with alterations in lymphoid organ microenvironment. Factor H is an abundant protein, synthesised in many cell types, and its reported binding to many different ligands, even if not of high affinity, may influence a large number of molecular interactions, together with the accepted role of Factor H within the complement system. Factor H is involved in mesenchymal stem cell mediated tolerance and also contributes to self-tolerance by augmenting iC3b production and opsonisation of apoptotic cells for their silent dendritic cell engulfment via complement receptor CR3, which mediates anti-inflammatory-tolerogenic effects in the apoptotic cell context. There may be co-operation with other phagocytic receptors, such as complement C1q receptors, and the Tim glycoprotein family, which specifically bind phosphatidylserine expressed on the apoptotic cell surface. Factor H is able to discriminate between self and nonself surfaces for self-protection and anti-microbe defence. Factor H, particularly as an abundant platelet protein, may also modulate blood coagulation, having an anti-thrombotic role. Here, we review a number of interaction pathways in coagulation and in immunity, together with associated diseases, and indicate where Factor H may be expected to exert an influence, based on reports of the diversity of ligands for Factor H. Copyright © 2017 Elsevier Ltd. All rights reserved.

The status of preimplantation genetic diagnosis in Japan: a criticism.

PubMed

Munné, Santiago; Cohen, Jacques

2004-09-01

Advances in preimplantation genetic diagnosis (PGD) are occurring worldwide. New clinics specializing in this approach to the control of disease genes or imbalanced chromosome numbers in human preimplantation embryos continue to increase. One exception is Japan, where the Japanese Society of Obstetrics and Gynecology disapproves of this practice because it discriminates against people with genetic abnormalities. Yet, some doctors there wish to introduce this method to help their couples to improved forms of IVF. This paper stresses the rights of patients to have a healthy baby, if necessary by the use of PGD. It argues against prohibition, since it complements the current nature of prenatal diagnosis and avoids the need for abortions in case of afflicted embryos. Consideration is also given to other attempts at restriction that have failed.

Recipient’s Genetic R702W NOD2 Variant Is Associated with an Increased Risk of Bacterial Infections after Orthotopic Liver Transplantation

PubMed Central

van Hoek, Bart; van den Berg, Arie P.; Porte, Robert J.; Blokzijl, Hans; Coenraad, Minneke J.; Hepkema, Bouke G.; Schaapherder, Alexander F.; Ringers, Jan; Weersma, Rinse K.; Verspaget, Hein W.

2013-01-01

Introduction Orthotopic liver transplantation (OLT) is accompanied by a significant postoperative infection risk. Immunosuppression to prevent rejection increases the susceptibility to infections, mainly by impairing the adaptive immune system. Genetic polymorphisms in the lectin complement pathway of the donor have recently been identified as important risk determinants of clinically significant bacterial infection (CSI) after OLT. Another genetic factor involved in innate immunity is NOD2, which was reported to be associated with increased risk of spontaneous bacterial peritonitis in cirrhotic patients. Methods We assessed association of three genetic NOD2 variants (R702W, G908R and 3020insC) with increased risk of CSI after OLT. 288 OLT recipient-donor pairs from two tertiary referral centers were genotyped for the three NOD2 variants. The probability of CSI in relation to NOD2 gene variants was determined with cumulative incidence curves and log-rank analysis. Results The R702W NOD2 variant in the recipient was associated with CSI after OLT. Eight out of 15 (53.3%) individuals with a mutated genotype compared to 80/273 (29.3%) with wild type genotype developed CSI (p=0.027, univariate cox regression), illustrated by a higher frequency of CSI after OLT over time (p=0.0003, log rank analysis). Multivariate analysis (including the donor lectin complement pathway profile) showed independence of this R702W NOD2 association from other risk factors (HR 2.0; p=0.04). The other NOD2 variants, G908R and 3020insC, in the recipient were not associated with CSI. There was no association with CSI after OLT for any of the NOD2 variants in the donor. Conclusion The mutated NOD2 R702W genotype in the recipient is independently associated with an increased risk of bacterial infections after liver transplantation, indicating a predisposing role for this genetic factor impairing the recipient’s innate immune system. PMID:23977330

Identifying Key Networks Linked to Light-Independent Photoreceptor Degeneration in Visual Arrestin 1 Knockout Mice.

PubMed

Kim, Hwa Sun; Huang, Shun-Ping; Lee, Eun-Jin; Craft, Cheryl Mae

2018-01-01

When visual arrestin 1 (ARR1, S-antigen, 48 KDa protein) was genetically knocked out in mice (original Arr1 -/- , designated Arr1 -/-A ), rod photoreceptors degenerated in a light-dependent manner. Subsequently, a light-independent cone dystrophy was identified with minimal rod death in ARR1 knockout mice (Arr1 -/-A Arr4 +/+ , designated Arr1 -/-B ), which were F2 littermates from breeding the original Arr1 -/-A and cone arrestin knockout 4 (Arr4 -/- ) mice. To resolve the genetic and phenotypic differences between the two ARR1 knockouts, we performed Affymetrix™ exon array analysis to focus on the potential differential gene expression profile and to explore the molecular and cellular pathways leading to this observed susceptibility to cone dystrophy in Arr1 -/-B compared to Arr1 -/-A or control Arr1 +/+ Arr4 +/+ (wild type [WT]). Only in the Arr1 -/-B retina did we observe an up-regulation of retinal transcripts involved in the immune response, inflammatory response and JAK-STAT signaling molecules, OSMRβ and phosphorylation of STAT3. Of these responses, the complement system was significantly higher, and a variety of inflammatory responses by complement regulation and anti-inflammatory cytokine or factors were identified in Arr1 -/-B retinal transcripts. This discovery supports that Arr1 -/-B has a distinct genetic background from Arr1 -/-A that results in alterations in its retinal phenotype leading to susceptibility to cone degeneration induced by inappropriate inflammatory and immune responses.

A Novel ESX-1 Locus Reveals that Surface-Associated ESX-1 Substrates Mediate Virulence in Mycobacterium marinum

PubMed Central

Kennedy, George M.; Hooley, Gwendolyn C.; Champion, Matthew M.; Mba Medie, Felix

2014-01-01

EsxA (ESAT-6) and EsxB (CFP-10) are virulence factors exported by the ESX-1 system in mycobacterial pathogens. In Mycobacterium marinum, an established model for ESX-1 secretion in Mycobacterium tuberculosis, genes required for ESX-1 export reside at the extended region of difference 1 (RD1) locus. In this study, a novel locus required for ESX-1 export in M. marinum was identified outside the RD1 locus. An M. marinum strain bearing a transposon-insertion between the MMAR_1663 and MMAR_1664 genes exhibited smooth-colony morphology, was deficient for ESX-1 export, was nonhemolytic, and was attenuated for virulence. Genetic complementation revealed a restoration of colony morphology and a partial restoration of virulence in cell culture models. Yet hemolysis and the export of ESX-1 substrates into the bacteriological medium in vitro as measured by both immunoblotting and quantitative proteomics were not restored. We show that genetic complementation of the transposon insertion strain partially restored the translocation of EsxA and EsxB to the mycobacterial cell surface. Our findings indicate that the export of EsxA and EsxB to the cell surface, rather than secretion into the bacteriological medium, correlates with virulence in M. marinum. Together, these findings not only expand the known genetic loci required for ESX-1 secretion in M. marinum but also provide an explanation for the observed disparity between in vitro ESX-1 export and virulence. PMID:24610712

Cytogenetic Analysis of the South American Fruit Fly Anastrepha fraterculus (Diptera:Tephritidae) Species Complex: Construction of Detailed Photographic Polytene Chromosome Maps of the Argentinian Af. sp.1 Member

PubMed Central

Augustinos, Antonios A.; Drosopoulou, Elena; Lanzavecchia, Silvia B.; Cladera, Jorge L.; Caceres, Carlos; Bourtzis, Kostas; Mavragani-Tsipidou, Penelope; Zacharopoulou, Antigone

2016-01-01

Genetic and cytogenetic studies constitute a significant basis for understanding the biology of insect pests and the design and the construction of genetic tools for biological control strategies. Anastrepha fraterculus is an important pest of the Tephritidae family. It is distributed from southern Texas through eastern Mexico, Central America and South America causing significant crop damage and economic losses. Currently it is considered as a species complex; until now seven members have been described based on multidisciplinary approaches. Here we report the cytogenetic analysis of an Argentinian population characterized as Af. sp.1 member of the Anastrepha fraterculus species complex. The mitotic karyotype and the first detailed photographic maps of the salivary gland polytene chromosomes are presented. The mitotic metaphase complement consists of six (6) pairs of chromosomes, including one pair of heteromorphic sex chromosomes, with the male being the heterogametic sex. The analysis of the salivary gland polytene complement shows a total number of five long chromosomes that correspond to the five autosomes of the mitotic karyotype and a heterochromatic network corresponding to the sex chromosomes. Comparison of the polytene chromosome maps between this species and Anastrepha ludens shows significant similarity. The polytene maps presented here are suitable for cytogenetic studies that could shed light on the species limits within this species complex and support the development of genetic tools for sterile insect technique (SIT) applications. PMID:27362546

Role of Cystathionine β-Lyase in Catabolism of Amino Acids to Sulfur Volatiles by Genetic Variants of Lactobacillus helveticus CNRZ 32▿

PubMed Central

Lee, Won-Jae; Banavara, Dattatreya S.; Hughes, Joanne E.; Christiansen, Jason K.; Steele, James L.; Broadbent, Jeffery R.; Rankin, Scott A.

2007-01-01

Catabolism of sulfur-containing amino acids plays an important role in the development of cheese flavor. During ripening, cystathionine β-lyase (CBL) is believed to contribute to the formation of volatile sulfur compounds (VSCs) such as methanethiol and dimethyl disulfide. However, the role of CBL in the generation of VSCs from the catabolism of specific sulfur-containing amino acids is not well characterized. The objective of this study was to investigate the role of CBL in VSC formation by Lactobacillus helveticus CNRZ 32 using genetic variants of L. helveticus CNRZ 32 including the CBL-null mutant, complementation of the CBL-null mutant, and the CBL overexpression mutant. The formation of VSCs from methionine, cystathionine, and cysteine was determined in a model system using gas chromatography-mass spectrometry with solid-phase microextraction. With methionine as a substrate, CBL overexpression resulted in higher VSC production than that of wild-type L. helveticus CNRZ 32 or the CBL-null mutant. However, there were no differences in VSC production between the wild type and the CBL-null mutant. With cystathionine, methanethiol production was detected from the CBL overexpression variant and complementation of the CBL-null mutant, implying that CBL may be involved in the conversion of cystathionine to methanethiol. With cysteine, no differences in VSC formation were observed between the wild type and genetic variants, indicating that CBL does not contribute to the conversion of cysteine. PMID:17337535

Genetic Polymorphisms in XRCC1, CD3EAP, PPP1R13L, XPB, XPC, and XPF and the Risk of Chronic Benzene Poisoning in a Chinese Occupational Population.

PubMed

Xue, Ping; Gao, Lin; Xiao, Sha; Zhang, Guopei; Xiao, Mingyang; Zhang, Qianye; Zheng, Xiao; Cai, Yuan; Jin, Cuihong; Yang, Jinghua; Wu, Shengwen; Lu, Xiaobo

2015-01-01

Individual variations in the capacity of DNA repair machinery to relieve benzene-induced DNA damage may be the key to developing chronic benzene poisoning (CBP), an increasingly prevalent occupational disease in China. ERCC1 (Excision repair cross complementation group 1) is located on chromosome 19q13.2-3 and participates in the crucial steps of Nucleotide Excision Repair (NER); moreover, we determined that one of its polymorphisms, ERCC1 rs11615, is a biomarker for CBP susceptibility in our previous report. Our aim is to further explore the deeper association between some genetic variations related to ERCC1 polymorphisms and CBP risk. Nine single nucleotide polymorphisms (SNPs) of XRCC1 (X-ray repair cross-complementing 1), CD3EAP (CD3e molecule, epsilon associated protein), PPP1R13L (protein phosphatase 1, regulatory subunit 13 like), XPB (Xeroderma pigmentosum group B), XPC (Xeroderma pigmentosum group C) and XPF (Xeroderma pigmentosum group F) were genotyped by the Snapshot and TaqMan-MGB® probe techniques, in a study involving 102 CBP patients and 204 controls. The potential interactions between these SNPs and lifestyle factors, such as smoking and drinking, were assessed using a stratified analysis. An XRCC1 allele, rs25487, was related to a higher risk of CBP (P<0.001) even after stratifying for potential confounders. Carriers of the TT genotype of XRCC1 rs1799782 who were alcohol drinkers (OR = 8.000; 95% CI: 1.316-48.645; P = 0.022), male (OR = 9.333; 95% CI: 1.593-54.672; P = 0.019), and had an exposure of ≤12 years (OR = 2.612; 95% CI: 1.048-6.510; P = 0.035) had an increased risk of CBP. However, the T allele in PPP1R13L rs1005165 (P<0.05) and the GA allele in CD3EAP rs967591 (OR = 0.162; 95% CI: 0039~0.666; P = 0.037) decreased the risk of CBP in men. The haplotype analysis of XRCC1 indicated that XRCC1 rs25487A, rs25489G and rs1799782T (OR = 15.469; 95% CI: 5.536-43.225; P<0.001) were associated with a high risk of CBP. The findings showed that the rs25487 and rs1799782 polymorphisms of XRCC1 may contribute to an individual's susceptibility to CBP and may be used as valid biomarkers. Overall, the genes on chromosome 19q13.2-3 may have a special significance in the development of CBP in occupationally exposed Chinese populations.

Genetic Polymorphisms in XRCC1, CD3EAP, PPP1R13L, XPB, XPC, and XPF and the Risk of Chronic Benzene Poisoning in a Chinese Occupational Population

PubMed Central

Xiao, Sha; Zhang, Guopei; Xiao, Mingyang; Zhang, Qianye; Zheng, Xiao; Cai, Yuan; Jin, Cuihong; Yang, Jinghua; Wu, Shengwen; Lu, Xiaobo

2015-01-01

Objectives Individual variations in the capacity of DNA repair machinery to relieve benzene-induced DNA damage may be the key to developing chronic benzene poisoning (CBP), an increasingly prevalent occupational disease in China. ERCC1 (Excision repair cross complementation group 1) is located on chromosome 19q13.2–3 and participates in the crucial steps of Nucleotide Excision Repair (NER); moreover, we determined that one of its polymorphisms, ERCC1 rs11615, is a biomarker for CBP susceptibility in our previous report. Our aim is to further explore the deeper association between some genetic variations related to ERCC1 polymorphisms and CBP risk. Methods Nine single nucleotide polymorphisms (SNPs) of XRCC1 (X-ray repair cross-complementing 1), CD3EAP (CD3e molecule, epsilon associated protein), PPP1R13L (protein phosphatase 1, regulatory subunit 13 like), XPB (Xeroderma pigmentosum group B), XPC (Xeroderma pigmentosum group C) and XPF (Xeroderma pigmentosum group F) were genotyped by the Snapshot and TaqMan-MGB® probe techniques, in a study involving 102 CBP patients and 204 controls. The potential interactions between these SNPs and lifestyle factors, such as smoking and drinking, were assessed using a stratified analysis. Results An XRCC1 allele, rs25487, was related to a higher risk of CBP (P<0.001) even after stratifying for potential confounders. Carriers of the TT genotype of XRCC1 rs1799782 who were alcohol drinkers (OR = 8.000; 95% CI: 1.316–48.645; P = 0.022), male (OR = 9.333; 95% CI: 1.593–54.672; P = 0.019), and had an exposure of ≤12 years (OR = 2.612; 95% CI: 1.048–6.510; P = 0.035) had an increased risk of CBP. However, the T allele in PPP1R13L rs1005165 (P<0.05) and the GA allele in CD3EAP rs967591 (OR = 0.162; 95% CI: 0039~0.666; P = 0.037) decreased the risk of CBP in men. The haplotype analysis of XRCC1 indicated that XRCC1 rs25487A, rs25489G and rs1799782T (OR = 15.469; 95% CI: 5.536–43.225; P<0.001) were associated with a high risk of CBP. Conclusions The findings showed that the rs25487 and rs1799782 polymorphisms of XRCC1 may contribute to an individual’s susceptibility to CBP and may be used as valid biomarkers. Overall, the genes on chromosome 19q13.2–3 may have a special significance in the development of CBP in occupationally exposed Chinese populations. PMID:26681190

Stimulation of complement component C3 synthesis in macrophagelike cell lines by group B streptococci.

PubMed Central

Goodrum, K J

1987-01-01

Complement levels and complement activation are key determinants in streptococcus-induced inflammatory responses. Activation of macrophage functions, such as complement synthesis, by group B streptococci (GBS) was examined as a possible component of GBS-induced chronic inflammation. Using an enzyme-linked immunosorbent assay, secreted C3 from mouse macrophagelike cell lines (PU5-1.8 and J774A.1) was monitored after cultivation with GBS. Whole, heat-killed GBS (1 to 10 CFU per macrophage) of both type Ia and III strains induced 25 to 300% increases in secreted C3 in both cell lines after a 24-h cultivation. GBS-treated cell lines exhibited increases in secreted lysozyme (10%) and in cellular protein (25 to 50%). Inhibition of macrophage phagocytosis by cytochalasin B inhibited GBS stimulation of C3. Purified cell walls of GBS type III strain 603-79 (1 to 10 micrograms/ml) also enhanced C3 synthesis. Local enhancement of macrophage C3 production by ingested streptococci or by persistent cell wall antigens may serve to promote chronic inflammatory responses. PMID:3552987

Phenotypic characterization of 10 methanol oxidation mutant classes in Methylobacterium sp. strain AM1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nunn, D.N.; Lidstrom, M.E.

Twenty-five methanol oxidation mutants of the facultative methylotroph Methylobacterium sp. strain AM1 have been characterized by complementation analysis and assigned to 10 complementation groups, Mox A1, A2, A3, and B through H. In this study we have characterized each of the mutants belonging to the 10 Mox complementation groups for the following criteria: (i) phenazine methosulfate-dichlorophenolindophenol dye-linked methanol dehydrogenase activity; (ii) methanol-dependent whole-cell oxygen consumption; (iii) the presence or absence of methanol dehydrogenase protein by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blotting; (iv) the absorption spectra of purified mutant methanol dehydrogenase proteins; and (v) the presence or absence ofmore » the soluble cytochrome c proteins of Methylobacterium sp. strain AM1, as determined by reduced-oxidized difference spectra and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. With this information, we have proposed functions for each of the genes deficient in the mutants of the 10 Mox complementation groups. These proposed gene functions include two linked genes that encode the methanol dehydrogenase structural protein and the soluble cytochrome c/sub L/, a gene encoding a secretion function essential for the synthesis and export of methanol dehydrogenase and cytochrome c/sub L/, three gene functions responsible for the proper association of the pyrrolo-quinoline quinone prosthetic group with the methanol dehydrogenase apoprotein, and four positive regulatory gene functions controlling the expression of the ability to oxidize methanol.« less

Low copy numbers of complement C4 and homozygous deficiency of C4A may predispose to severe disease and earlier disease onset in patients with systemic lupus erythematosus.

PubMed

Jüptner, M; Flachsbart, F; Caliebe, A; Lieb, W; Schreiber, S; Zeuner, R; Franke, A; Schröder, J O

2018-04-01

Objectives Low copy numbers and deletion of complement C4 genes are potent risk factors for systemic lupus erythematosus (SLE). However, it is not known whether this genetic association affects the clinical outcome. We investigated C4 copy number variation and its relationship to clinical and serological features in a Northern European lupus cohort. Methods We genotyped the C4 gene locus using polymerase chain reaction (PCR)-based TaqMan assays in 169 patients with SLE classified according to the 1997 revised American College of Rheumatology (ACR) criteria and in 520 matched controls. In the patient group the mean C4 serum protein concentrations nephelometrically measured during a 12-month period prior to genetic analysis were compared to C4 gene copy numbers. Severity of disease was classified according to the intensity of the immunosuppressive regimens applied and compared to C4 gene copy numbers, too. In addition, we performed a TaqMan based analysis of three lupus-associated single-nucleotide polymorphisms (SNPs) located inside the major histocompatibility complex (MHC) to investigate the independence of complement C4 in association with SLE. Results Homozygous deficiency of the C4A isotype was identified as the strongest risk factor for SLE (odds ratio (OR) = 5.329; p = 7.7 × 10 -3 ) in the case-control comparison. Moreover, two copies of total C4 were associated with SLE (OR = 3.699; p = 6.8 × 10 -3 ). C4 serum levels were strongly related to C4 gene copy numbers in patients, the mean concentration ranging from 0.110 g/l (two copies) to 0.256 g/l (five to six copies; p = 4.9 × 10 -6 ). Two copies of total C4 and homozygous deletion of C4A were associated with a disease course requiring cyclophosphamide therapy (OR = 4.044; p = 0.040 and OR = 5.798; p = 0.034, respectively). Homozygous deletion of C4A was associated with earlier onset of SLE (median 24 vs. 34 years; p = 0.019) but not significant after correction for multiple testing. SNP analysis revealed a significant association of HLA-DRB1*0301 with SLE (OR = 2.231; p = 1.33 × 10 -5 ). Conclusions Our findings confirm the important role of complement C4 genes in the development of SLE. Beyond the impact on the susceptibility for lupus, C4 copy numbers may be related to earlier onset and a more severe course of the disease. The association of homozygous deletion of C4A and SLE is accompanied by the presence of HLA-DRB1*0301 without a proven pathophysiological mechanism.

Fanconi anemia in Tunisia: high prevalence of group A and identification of new FANCA mutations.

PubMed

Bouchlaka, Chiraz; Abdelhak, Sonia; Amouri, Ahlem; Ben Abid, Hela; Hadiji, Sondes; Frikha, Mounir; Ben Othman, Tarek; Amri, Fethi; Ayadi, Hammadi; Hachicha, Mongia; Rebaï, Ahmed; Saad, Ali; Dellagi, Koussay

2003-01-01

Fanconi anemia (FA) is a rare autosomal recessive disease characterized by progressive pancytopenia, congenital malformations, and predisposition to acute myeloid leukemia. Fanconi anemia is genetically heterogeneous, with at least eight distinct complementation groups of FA (A, B, C, D1, D2, E, F, and G) having been defined by somatic cell fusion studies. Six genes (FANCA, FANCC, FANCD2, FANCE, FANCG, and FANCF) have been cloned. Mutations of the seventh Fanconi anemia gene, BRCA2, have been shown to lead to FAD1 and probably FAB groups. In order to characterize the molecular defects underlying FA in Tunisia, 39 families were genotyped with microsatellite markers linked to known FA gene. Haplotype analysis and homozygosity mapping assigned 43 patients belonging to 34 families to the FAA group, whereas one family was probably not linked to the FANCA gene or to any known FA genes. For patients belonging to the FAA group, screening for mutations revealed four novel mutations: two small homozygous deletions 1693delT and 1751-1754del, which occurred in exon 17 and exon 19, respectively, and two transitions, viz., 513G-->A in exon 5 and A-->G at position 166 (IVS24+166A-->G) of intron 24. Two new polymorphisms were also identified in intron 24 (IVS24-5G/A and IVS24-6C/G).

The Generation and Genetic Analysis of Suppressors of Lethal Mutations in the Caenorhabditis Elegans Rol-3(v) Gene

PubMed Central

Barbazuk, W. B.; Johnsen, R. C.; Baillie, D. L.

1994-01-01

The Caenorhabditis elegans rol-3(e754) mutation is a member of a general glass of mutations affecting gross morphology, presumably through disruption of the nematode cuticle. Adult worms homozygous for rol-3(e754) exhibit rotation about their long axis associated with a left-hand twisted cuticle, musculature, gut and ventral nerve cord. Our laboratory previously isolated 12 recessive lethal alleles of rol-3. All these lethal alleles cause an arrest in development at either early or mid-larval stages, suggesting that the rol-3 gene product performs an essential developmental function. Furthermore, through the use of the heterochronic mutants lin-14 and lin-29, we have established that the expression of rol-3(e754)'s adult specific visible function is not dependent on the presence of an adult cuticle. In an attempt to understand rol-3's developmental role we sought to identify other genes whose products interact with that of rol-3. Toward this end, we generated eight EMS induced and two gamma irradiation-induced recessive suppressors of the temperature sensitive (ts) mid-larval lethal phenotype of rol-3(s1040ts). These suppressors define two complementation groups srl-1 II and srl-2 III; and, while they suppress the rol-3(s1040) lethality, they do not suppress the adult specific visible rolling phenotype. Furthermore, there is a complex genetic interaction between srl-2 and srl-1 such that srl-2(s2506) fails to complement all srl alleles tested. These results suggest that srl-1 and srl-2 may share a common function and, thus, possibly constitute members of the same gene family. Mutations in both srl-1 and srl-2 produce no obvious hermaphrodite phenotypes in the absence of rol-3(s1040ts); however, males homozygous for either srl-1 or srl-2 display aberrant tail morphology. We present evidence suggesting that the members of srl-2 are not allele specific with respect to their suppression of rol-3 lethality, and that rol-3 may act in some way to influence proper posterior morphogenesis. Finally, based on our genetic analysis of rol-3 and the srl mutations, we present a model whereby the wild-type products of the srl loci act in a concerted manner to negatively regulate the rol-3 gene. PMID:8138151

Recent insights into C3 glomerulopathy

PubMed Central

Barbour, Thomas D.; Pickering, Matthew C.; Cook, H. Terence

2013-01-01

‘C3 glomerulopathy’ is a recent disease classification comprising several rare types of glomerulonephritis (GN), including dense deposit disease (DDD), C3 glomerulonephritis (C3GN) and CFHR5 nephropathy. These disorders share the key histological feature of isolated complement C3 deposits in the glomerulus. A common aetiology involving dysregulation of the alternative pathway (AP) of complement has been elucidated in the past decade, with genetic defects and/or autoantibodies able to be identified in a proportion of patients. We review the clinical and histological features of C3 glomerulopathy, relating these to underlying molecular mechanisms. The role of uncontrolled C3 activation in pathogenesis is emphasized, with important lessons from animal models. Methods, advantages and limitations of gene testing in the assessment of individuals or families with C3 glomerulopathy are discussed. While no therapy has yet been shown consistently effective, clinical evaluation of agents targeting specific components of the complement system is ongoing. However, limits to current knowledge regarding the natural history and the appropriate timing and duration of proposed therapies need to be addressed. PMID:23479095

Identification and Characterization of Mutations Affecting Sporulation in Saccharomyces Cerevisiae

PubMed Central

Smith, L. M.; Robbins, L. G.; Kennedy, A.; Magee, P. T.

1988-01-01

Mutations affecting the synthesis of the sporulation amyloglucosidase were isolated in a homothallic strain of Saccharomyces cerevisiae, SCMS7-1. Two were found, both of which were deficient in sporulation at 34°. One, SL484, sporulated to 50% normal levels at 30° but less than 5% at 34° or 22°. The other, SL641, failed to sporulate at any temperature. Both mutants were blocked before premeiotic DNA synthesis, and both complemented spo1, spo3, and spo7. Genetic analysis of the mutation in SL484 indicated linkage to TRP5 and placed the gene 10 map units from TRP5 on chromosome VII. A plasmid containing an insert which complements the mutation in SL484 fails to complement SL641. We therefore conclude that these two mutations are in separate genes and we propose to call these genes SPO17 and SPO18. These two genes are (with SPO7, SPO8, and SPO9) among the earliest identified in the sporulation pathway and may interact directly with the positive and negative regulators RME and IME. PMID:3147221

DNA barcoding of Cuban freshwater fishes: evidence for cryptic species and taxonomic conflicts.

PubMed

Lara, Ariagna; Ponce de León, José Luis; Rodríguez, Rodet; Casane, Didier; Côté, Guillaume; Bernatchez, Louis; García-Machado, Erik

2010-05-01

Despite ongoing efforts to protect species and ecosystems in Cuba, habitat degradation, overuse and introduction of alien species have posed serious challenges to native freshwater fish species. In spite of the accumulated knowledge on the systematics of this freshwater ichthyofauna, recent results suggested that we are far from having a complete picture of the Cuban freshwater fish diversity. It is estimated that 40% of freshwater Cuban fish are endemic; however, this number may be even higher. Partial sequences (652 bp) of the mitochondrial gene COI (cytochrome c oxidase subunit I) were used to barcode 126 individuals, representing 27 taxonomically recognized species in 17 genera and 10 families. Analysis was based on Kimura 2-parameter genetic distances, and for four genera a character-based analysis (population aggregation analysis) was also used. The mean conspecific, congeneric and confamiliar genetic distances were 0.6%, 9.1% and 20.2% respectively. Molecular species identification was in concordance with current taxonomical classification in 96.4% of cases, and based on the neighbour-joining trees, in all but one instance, members of a given genera clustered within the same clade. Within the genus Gambusia, genetic divergence analysis suggests that there may be at least four cryptic species. In contrast, low genetic divergence and a lack of diagnostic sites suggest that Rivulus insulaepinorum may be conspecific with Rivulus cylindraceus. Distance and character-based analysis were completely concordant, suggesting that they complement species identification. Overall, the results evidenced the usefulness of the DNA barcodes for cataloguing Cuban freshwater fish species and for identifying those groups that deserve further taxonomic attention. © 2009 Blackwell Publishing Ltd.

Uniparental genetic heritage of belarusians: encounter of rare middle eastern matrilineages with a central European mitochondrial DNA pool.

PubMed

Kushniarevich, Alena; Sivitskaya, Larysa; Danilenko, Nina; Novogrodskii, Tadeush; Tsybovsky, Iosif; Kiseleva, Anna; Kotova, Svetlana; Chaubey, Gyaneshwer; Metspalu, Ene; Sahakyan, Hovhannes; Bahmanimehr, Ardeshir; Reidla, Maere; Rootsi, Siiri; Parik, Jüri; Reisberg, Tuuli; Achilli, Alessandro; Hooshiar Kashani, Baharak; Gandini, Francesca; Olivieri, Anna; Behar, Doron M; Torroni, Antonio; Davydenko, Oleg; Villems, Richard

2013-01-01

Ethnic Belarusians make up more than 80% of the nine and half million people inhabiting the Republic of Belarus. Belarusians together with Ukrainians and Russians represent the East Slavic linguistic group, largest both in numbers and territory, inhabiting East Europe alongside Baltic-, Finno-Permic- and Turkic-speaking people. Till date, only a limited number of low resolution genetic studies have been performed on this population. Therefore, with the phylogeographic analysis of 565 Y-chromosomes and 267 mitochondrial DNAs from six well covered geographic sub-regions of Belarus we strove to complement the existing genetic profile of eastern Europeans. Our results reveal that around 80% of the paternal Belarusian gene pool is composed of R1a, I2a and N1c Y-chromosome haplogroups - a profile which is very similar to the two other eastern European populations - Ukrainians and Russians. The maternal Belarusian gene pool encompasses a full range of West Eurasian haplogroups and agrees well with the genetic structure of central-east European populations. Our data attest that latitudinal gradients characterize the variation of the uniparentally transmitted gene pools of modern Belarusians. In particular, the Y-chromosome reflects movements of people in central-east Europe, starting probably as early as the beginning of the Holocene. Furthermore, the matrilineal legacy of Belarusians retains two rare mitochondrial DNA haplogroups, N1a3 and N3, whose phylogeographies were explored in detail after de novo sequencing of 20 and 13 complete mitogenomes, respectively, from all over Eurasia. Our phylogeographic analyses reveal that two mitochondrial DNA lineages, N3 and N1a3, both of Middle Eastern origin, might mark distinct events of matrilineal gene flow to Europe: during the mid-Holocene period and around the Pleistocene-Holocene transition, respectively.

Evolution of complement as an effector system in innate and adaptive immunity.

PubMed

Sunyer, J Oriol; Boshra, Hani; Lorenzo, Gema; Parra, David; Freedman, Bruce; Bosch, Nina

2003-01-01

For a long time, the complement system in mammals has been regarded as a biological system that plays an essential role in innate immunity. More recently, it has been recognized that the complement system contributes heavily to the generation and development of an acquired immune response. In fact, this ancient mechanism of defense has evolved from a primitive mechanism of innate immune recognition in invertebrate species to that of an effector system that bridges the innate with the adaptive immune response in vertebrate species. When and how did complement evolve into a shared effector system between innate and adaptive immunity? To answer this question, our group is interested in understanding the role of complement in innate and adaptive immune responses in an evolutionary relevant species: the teleost fish. The attractiveness of this species as an animal model is based on two important facts. First, teleost fish are one of the oldest animal species to have developed an adaptive immune response. Second, the complement system of teleost fish offers a unique feature, which is the structural and functional diversity of its main effector protein, C3, the third component of the complement system.

Clinical endpoints for developing pharmaceuticals to manage patients with sporadic or genetic risk of colorectal cancer

PubMed Central

Rial, Nathaniel S.; Zell, Jason A.; Cohen, Alfred M.; Gerner, Eugene W.

2013-01-01

To reduce the morbidity and mortality from colorectal cancer, current clinical practice focuses on screening for early detection and polypectomy as a form of secondary prevention, complemented with surgical interventions when appropriate. No pharmaceutical agent is currently approved for use in clinical practice for the management of patients with risk of colorectal cancer. This article will review earlier attempts to develop pharmaceuticals for use in managing patients with sporadic or genetic risk of colorectal cancer. It will also discuss therapeutic endpoints under evaluation in current efforts to develop drugs for treating colorectal cancer risk factors. PMID:22928902

[Genetically modified plants and food safety. State of the art and discussion in the European Union].

PubMed

Schauzu, M

2004-09-01

Placing genetically modified (GM) plants and derived products on the European Union's (EU) market has been regulated by a Community Directive since 1990. This directive was complemented by a regulation specific for genetically modified and other novel foods in 1997. Specific labelling requirements have been applicable for GM foods since 1998. The law requires a pre-market safety assessment for which criteria have been elaborated and continuously adapted in accordance with the state of the art by national and international bodies and organisations. Consequently, only genetically modified products that have been demonstrated to be as safe as their conventional counterparts can be commercialized. However, the poor acceptance of genetically modified foods has led to a de facto moratorium since 1998. It is based on the lack of a qualified majority of EU member states necessary for authorization to place genetically modified plants and derived foods on the market. New Community Regulations are intended to end this moratorium by providing a harmonized and transparent safety assessment, a centralised authorization procedure, extended labelling provisions and a traceability system for genetically modified organisms (GMO) and derived food and feed.

Estimation of the frequency of occult mutations for an autosomal recessive disease in the presence of genetic heterogeneity: application to genetic hearing loss disorders.

PubMed

Kimberling, William J

2005-11-01

The routine testing for pathologic mutation(s) in a patient's DNA has become the foundation of modern molecular genetic diagnosis. It is especially valuable when the phenotype shows genetic heterogeneity, and its importance will grow as treatments become genotype specific. However, the technology of mutation detection is imperfect and mutations are often missed. This can be especially troublesome when dealing with a recessive disorder where the combination of genetic heterogeneity and missed mutation creates an imprecision in the genotypic assessment of individuals who do not appear to have the expected complement of two pathologic mutations. This article describes a statistical approach to the estimation of the likelihood of a genetic diagnosis under these conditions. In addition to providing a means of testing for missed mutations, it also provides a method of estimating and testing for the presence of genetic heterogeneity in the absence of linkage data. Gene frequencies as well as estimates of sensitivity and specificity can be obtained as well. The test is applied to GJB2 recessive nonsyndromic deafness, Usher syndrome types Ib and IIa, and Pendred-enlarged vestibular aqueduct syndrome. Copyright 2005 Wiley-Liss, Inc.

Vitamin D. Treatment of Prostate Cancer: The Inhibitory Role of IGFBP-3

DTIC Science & Technology

2005-01-01

cassette, sub-family C (CFTR/MRP), member 6 AA424804 Flag 1.62 2.36 Xeroderma pigmentosum , complementation group C (XPC) AA287323 1.44 1.83 2.25...expressed gene I (POVI) T72067 2.37 7.30 Xeroderma pigmentosum , complementation group C (XPC) AA287323 2.25 11.2 Claudin 4 AA506754 2.21 7.30 UDP...Diego: Academic Press; 2001. in DNA damage response ( xeroderma pigmentosum pp 257-303. compledamentatgerouponse C e r [e 3. Miller GJ. Vitamin D and

Practical aspects of genetic identification of hallucinogenic and other poisonous mushrooms for clinical and forensic purposes

PubMed Central

Kowalczyk, Marek; Sekuła, Andrzej; Mleczko, Piotr; Olszowy, Zofia; Kujawa, Anna; Zubek, Szymon; Kupiec, Tomasz

2015-01-01

Aim To assess the usefulness of a DNA-based method for identifying mushroom species for application in forensic laboratory practice. Methods Two hundred twenty-one samples of clinical forensic material (dried mushrooms, food remains, stomach contents, feces, etc) were analyzed. ITS2 region of nuclear ribosomal DNA (nrDNA) was sequenced and the sequences were compared with reference sequences collected from the National Center for Biotechnology Information gene bank (GenBank). Sporological identification of mushrooms was also performed for 57 samples of clinical material. Results Of 221 samples, positive sequencing results were obtained for 152 (69%). The highest percentage of positive results was obtained for samples of dried mushrooms (96%) and food remains (91%). Comparison with GenBank sequences enabled identification of all samples at least at the genus level. Most samples (90%) were identified at the level of species or a group of closely related species. Sporological and molecular identification were consistent at the level of species or genus for 30% of analyzed samples. Conclusion Molecular analysis identified a larger number of species than sporological method. It proved to be suitable for analysis of evidential material (dried hallucinogenic mushrooms) in forensic genetic laboratories as well as to complement classical methods in the analysis of clinical material. PMID:25727040

Genome-Wide Requirements for Resistance to Functionally Distinct DNA-Damaging Agents

PubMed Central

Proctor, Michael; Flaherty, Patrick; Jordan, Michael I; Arkin, Adam P; Davis, Ronald W; Nislow, Corey; Giaever, Guri

2005-01-01

The mechanistic and therapeutic differences in the cellular response to DNA-damaging compounds are not completely understood, despite intense study. To expand our knowledge of DNA damage, we assayed the effects of 12 closely related DNA-damaging agents on the complete pool of ~4,700 barcoded homozygous deletion strains of Saccharomyces cerevisiae. In our protocol, deletion strains are pooled together and grown competitively in the presence of compound. Relative strain sensitivity is determined by hybridization of PCR-amplified barcodes to an oligonucleotide array carrying the barcode complements. These screens identified genes in well-characterized DNA-damage-response pathways as well as genes whose role in the DNA-damage response had not been previously established. High-throughput individual growth analysis was used to independently confirm microarray results. Each compound produced a unique genome-wide profile. Analysis of these data allowed us to determine the relative importance of DNA-repair modules for resistance to each of the 12 profiled compounds. Clustering the data for 12 distinct compounds uncovered both known and novel functional interactions that comprise the DNA-damage response and allowed us to define the genetic determinants required for repair of interstrand cross-links. Further genetic analysis allowed determination of epistasis for one of these functional groups. PMID:16121259

Genetic control of enhanced mutability of mitochondrial DNA and gamma-ray sensitivity in Saccharomyces cerevisiae.

PubMed Central

Foury, F; Goffeau, A

1979-01-01

Five nuclear mutants enhancing the spontaneous mutation rate of mtDNA have been isolated in Saccharomyces cerevisiae. These mutators fall into five complementation groups and are located at five genetic loci different from rad50 to rad57 loci. Three mutants (gam1, gam2, and gam4), insensitive or weakly sensitive to gamma-rays, exhibit increased frequency of spontaneous production of mutants with large deletions of the mtDNA (p-) and of all tested mitochondrial drug-resistant mutants. Two other mutants (gam3 and gam5), highly sensitive to gamma-rays, increase only the mutation rate of particular alleles of the mtDNA. The mutant gam5 enhances only the production of p- and erythromycin-resistant clones. The mutant gam3 exhibits an enhanced rate of oligomycin-resistant clones as well as a collateral increase of nuclear mutability. The existence of gam3 and gam5 mutants indicates that at least two common steps control both nuclear DNA repair and the mutability of particular alleles of the mtDNA. However, the general spontaneous mutability of the mtDNA includes at least three steps not involved in the repair of nuclear DNA, as revealed by the gam1, gam2, and gam4 mutations. PMID:392521

Knowing one's place: a free-energy approach to pattern regulation

PubMed Central

Friston, Karl; Levin, Michael; Sengupta, Biswa; Pezzulo, Giovanni

2015-01-01

Understanding how organisms establish their form during embryogenesis and regeneration represents a major knowledge gap in biological pattern formation. It has been recently suggested that morphogenesis could be understood in terms of cellular information processing and the ability of cell groups to model shape. Here, we offer a proof of principle that self-assembly is an emergent property of cells that share a common (genetic and epigenetic) model of organismal form. This behaviour is formulated in terms of variational free-energy minimization—of the sort that has been used to explain action and perception in neuroscience. In brief, casting the minimization of thermodynamic free energy in terms of variational free energy allows one to interpret (the dynamics of) a system as inferring the causes of its inputs—and acting to resolve uncertainty about those causes. This novel perspective on the coordination of migration and differentiation of cells suggests an interpretation of genetic codes as parametrizing a generative model—predicting the signals sensed by cells in the target morphology—and epigenetic processes as the subsequent inversion of that model. This theoretical formulation may complement bottom-up strategies—that currently focus on molecular pathways—with (constructivist) top-down approaches that have proved themselves in neuroscience and cybernetics. PMID:25788538

Practical aspects of genetic identification of hallucinogenic and other poisonous mushrooms for clinical and forensic purposes.

PubMed

Kowalczyk, Marek; Sekuła, Andrzej; Mleczko, Piotr; Olszowy, Zofia; Kujawa, Anna; Zubek, Szymon; Kupiec, Tomasz

2015-02-01

To assess the usefulness of a DNA-based method for identifying mushroom species for application in forensic laboratory practice. Two hundred twenty-one samples of clinical forensic material (dried mushrooms, food remains, stomach contents, feces, etc) were analyzed. ITS2 region of nuclear ribosomal DNA (nrDNA) was sequenced and the sequen-ces were compared with reference sequences collected from the National Center for Biotechnology Information gene bank (GenBank). Sporological identification of mushrooms was also performed for 57 samples of clinical material. Of 221 samples, positive sequencing results were obtained for 152 (69%). The highest percentage of positive results was obtained for samples of dried mushrooms (96%) and food remains (91%). Comparison with GenBank sequences enabled identification of all samples at least at the genus level. Most samples (90%) were identified at the level of species or a group of closely related species. Sporological and molecular identification were consistent at the level of species or genus for 30% of analyzed samples. Molecular analysis identified a larger number of species than sporological method. It proved to be suitable for analysis of evidential material (dried hallucinogenic mushrooms) in forensic genetic laboratories as well as to complement classical methods in the analysis of clinical material.

Quantitative trait loci underlying resistance to sudden death syndrome (SDS) in MD96-5722 by 'Spencer' recombinant inbred line population of soybean.

PubMed

Anderson, J; Akond, M; Kassem, M A; Meksem, K; Kantartzi, S K

2015-04-01

The best way to protect yield loss of soybean [Glycine max (L.) Merr.] due to sudden death syndrome (SDS), caused by Fusarium virguliforme (Aoki, O'Donnel, Homma & Lattanzi), is the development and use of resistant lines. Mapping quantitative trait loci (QTL) linked to SDS help developing resistant soybean germplasm through molecular marker-assisted selection strategy. QTL for SDS presented herein are from a high-density SNP-based genetic linkage map of MD 96-5722 (a.k.a 'Monocacy') by 'Spencer' recombinant inbred line using SoySNP6K Illumina Infinium BeadChip genotyping array. Ninety-four F 5:7 lines were evaluated for 2 years (2010 and 2011) at two locations (Carbondale and Valmeyer) in southern Illinois, USA to identify QTL controlling SDS resistance using disease index (DX). Composite interval mapping identified 19 SDS controlling QTL which were mapped on 11 separate linkage group (LG) or chromosomes (Chr) out of 20 LG or Chr of soybean genome. Many of these significant QTL identified in one environment/year were confirmed in another year or environment, which suggests a common genetic effects and modes of the pathogen. These new QTL are useful sources for SDS resistance studies in soybean breeding, complementing previously reported loci.

Diversity, virulence, and antimicrobial resistance of the KPC-producing Klebsiella pneumoniae ST307 clone.

PubMed

Villa, Laura; Feudi, Claudia; Fortini, Daniela; Brisse, Sylvain; Passet, Virginie; Bonura, Celestino; Endimiani, Andrea; Mammina, Caterina; Ocampo, Ana Maria; Jimenez, Judy Natalia; Doumith, Michel; Woodford, Neil; Hopkins, Katie; Carattoli, Alessandra

2017-04-01

The global spread of Klebsiella pneumoniae producing Klebsiella pneumoniae carbapenemase (KPC) has been mainly associated with the dissemination of high-risk clones. In the last decade, hospital outbreaks involving KPC-producing K. pneumoniae have been predominantly attributed to isolates belonging to clonal group (CG) 258. However, results of recent epidemiological analysis indicate that KPC-producing sequence type (ST) 307, is emerging in different parts of the world and is a candidate to become a prevalent high-risk clone in the near future. Here we show that the ST307 genome encodes genetic features that may provide an advantage in adaptation to the hospital environment and the human host. Sequence analysis revealed novel plasmid-located virulence factors, including a cluster for glycogen synthesis. Glycogen production is considered to be one of the possible adaptive responses to long-term survival and growth in environments outside the host. Chromosomally-encoded virulence traits in the clone comprised fimbriae, an integrative conjugative element carrying the yersiniabactin siderophore, and two different capsular loci. Compared with the ST258 clone, capsulated ST307 isolates showed higher resistance to complement-mediated killing. The acquired genetic features identified in the genome of this new emerging clone may contribute to increased persistence of ST307 in the hospital environment and shed light on its potential epidemiological success.

An Experimental Study of the Use of Visual Illustrations Used to Complement Oral Instruction on Television.

ERIC Educational Resources Information Center

Dwyer, Francis M., Jr.

Five slide sequences, each containing 39 black-and-white slides designed to complement oral instruction, and carrying a 32 minute oral instructional unit on the heart, were presented to 269 college students in five groups through a television receiver. The purpose was twofold: to determine if redundant information presented simultaneously through…

Preferential association of a functional variant in complement receptor 2 with antibodies to double-stranded DNA

PubMed Central

Zhao, Jian; Giles, Brendan M; Taylor, Rhonda L; Yette, Gabriel A; Lough, Kara M; Ng, Han Leng; Abraham, Lawrence J; Wu, Hui; Kelly, Jennifer A; Glenn, Stuart B; Adler, Adam J; Williams, Adrienne H; Comeau, Mary E; Ziegler, Julie T; Marion, Miranda; Alarcón-Riquelme, Marta E; Alarcón, Graciela S; Anaya, Juan-Manuel; Bae, Sang-Cheol; Kim, Dam; Lee, Hye-Soon; Criswell, Lindsey A; Freedman, Barry I; Gilkeson, Gary S; Guthridge, Joel M; Jacob, Chaim O; James, Judith A; Kamen, Diane L; Merrill, Joan T; Sivils, Kathy Moser; Niewold, Timothy B; Petri, Michelle A; Ramsey-Goldman, Rosalind; Reveille, John D; Scofield, R Hal; Stevens, Anne M; Vilá, Luis M; Vyse, Timothy J; Kaufman, Kenneth M; Harley, John B; Langefeld, Carl D; Gaffney, Patrick M; Brown, Elizabeth E; Edberg, Jeffrey C; Kimberly, Robert P; Ulgiati, Daniela; Tsao, Betty P; Boackle, Susan A

2016-01-01

Objectives Systemic lupus erythematosus (SLE; OMIM 152700) is characterised by the production of antibodies to nuclear antigens. We previously identified variants in complement receptor 2 (CR2/CD21) that were associated with decreased risk of SLE. This study aimed to identify the causal variant for this association. Methods Genotyped and imputed genetic variants spanning CR2 were assessed for association with SLE in 15 750 case-control subjects from four ancestral groups. Allele-specific functional effects of associated variants were determined using quantitative real-time PCR, quantitative flow cytometry, electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP)-PCR. Results The strongest association signal was detected at rs1876453 in intron 1 of CR2 (pmeta=4.2×10−4, OR 0.85), specifically when subjects were stratified based on the presence of dsDNA autoantibodies (case-control pmeta=7.6×10−7, OR 0.71; case-only pmeta=1.9×10−4, OR 0.75). Although allele-specific effects on B cell CR2 mRNA or protein levels were not identified, levels of complement receptor 1 (CR1/CD35) mRNA and protein were significantly higher on B cells of subjects harbouring the minor allele (p=0.0248 and p=0.0006, respectively). The minor allele altered the formation of several DNA protein complexes by EMSA, including one containing CCCTC-binding factor (CTCF), an effect that was confirmed by ChIP-PCR. Conclusions These data suggest that rs1876453 in CR2 has long-range effects on gene regulation that decrease susceptibility to lupus. Since the minor allele at rs1876453 is preferentially associated with reduced risk of the highly specific dsDNA autoantibodies that are present in preclinical, active and severe lupus, understanding its mechanisms will have important therapeutic implications. PMID:25180293

Two Types of Genetic Interaction Implicate the Whirligig Gene of Drosophila Melanogaster in Microtubule Organization in the Flagellar Axoneme

PubMed Central

Green, L. L.; Wolf, N.; McDonald, K. L.; Fuller, M. T.

1990-01-01

The mutant nc4 allele of whirligig (3-54.4) of Drosophila melanogaster fails to complement mutations in an α-tubulin locus, α1t, mutations in a β-tubulin locus, B2t, or a mutation in the haywire locus. However, wrl fails to map to any of the known α- or β-tubulin genes. The extragenic failure to complement could indicate that the wrl product participates in structural interactions with microtubule proteins. The whirligig locus appears to be haploinsufficient for male fertility. Both a deficiency of wrl and possible loss of function alleles obtained by reverting the failure to complement between wrl(nc4) and B2t(n) are dominant male sterile in a genetic background wild type for tubulin. The dominant male sterility of the revertant alleles is suppressed if the flies are also heterozygous for B2t(n), for a deficiency of α1t, or for the hay(nc2) allele. These results suggest that it is not the absolute level of wrl gene product but its level relative to tubulin or microtubule function that is important for normal spermatogenesis. The phenotype of homozygous wrl mutants suggests that the whirligig product plays a role in postmeiotic spermatid differentiation, possibly in organizing the microtubules of the sperm flagellar axoneme. Flies homozygous for either wrl(nc4) or revertant alleles are viable and female fertile but male sterile. Premeiotic and meiotic stages of spermatogenesis appear normal. However, in post-meiotic stages, flagellar axonemes show loss of the accessory microtubule on the B-subfiber of outer doublet microtubules, outer triplet instead of outer doublet microtubules, and missing central pair microtubules. PMID:2127579

Novel genetic tools for diaminopimelic acid selection in virulence studies of Yersinia pestis.

PubMed

Bland, David M; Eisele, Nicholas A; Keleher, Lauren L; Anderson, Paul E; Anderson, Deborah M

2011-03-02

Molecular studies of bacterial virulence are enhanced by expression of recombinant DNA during infection to allow complementation of mutants and expression of reporter proteins in vivo. For highly pathogenic bacteria, such as Yersinia pestis, these studies are currently limited because deliberate introduction of antibiotic resistance is restricted to those few which are not human treatment options. In this work, we report the development of alternatives to antibiotics as tools for host-pathogen research during Yersinia pestis infections focusing on the diaminopimelic acid (DAP) pathway, a requirement for cell wall synthesis in eubacteria. We generated a mutation in the dapA-nlpB(dapX) operon of Yersinia pestis KIM D27 and CO92 which eliminated the expression of both genes. The resulting strains were auxotrophic for diaminopimelic acid and this phenotype was complemented in trans by expressing dapA in single and multi-copy. In vivo, we found that plasmids derived from the p15a replicon were cured without selection, while selection for DAP enhanced stability without detectable loss of any of the three resident virulence plasmids. The dapAX mutation rendered Y. pestis avirulent in mouse models of bubonic and septicemic plague which could be complemented when dapAX was inserted in single or multi-copy, restoring development of disease that was indistinguishable from the wild type parent strain. We further identified a high level, constitutive promoter in Y. pestis that could be used to drive expression of fluorescent reporters in dapAX strains that had minimal impact to virulence in mouse models while enabling sensitive detection of bacteria during infection. Thus, diaminopimelic acid selection for single or multi-copy genetic systems in Yersinia pestis offers an improved alternative to antibiotics for in vivo studies that causes minimal disruption to virulence.

Complement C4 deficiency--a plausible risk factor for non-tuberculous mycobacteria (NTM) infection in apparently immunocompetent patients.

PubMed

Kotilainen, Hannele; Lokki, Marja-Liisa; Paakkanen, Riitta; Seppänen, Mikko; Tukiainen, Pentti; Meri, Seppo; Poussa, Tuija; Eskola, Jussi; Valtonen, Ville; Järvinen, Asko

2014-01-01

Non-tuberculous mycobacteria (NTM) are ubiquitous in the environment and they infect mainly persons with underlying pulmonary diseases but also previously healthy elderly women. Defects in host resistance that lead to pulmonary infections by NTM are relatively unknown. A few genetic defects have been associated with both pulmonary and disseminated mycobacterial infections. Rare disseminated NTM infections have been associated with genetic defects in T-cell mediated immunity and in cytokine signaling in families. We investigated whether there was an association between NTM infections and deficiencies of complement components C4A or C4B that are encoded by major histocompatibility complex (MHC). 50 adult patients with a positive NTM culture with symptoms and findings of a NTM disease were recruited. Patients' clinical history was collected and symptoms and clinical findings were categorized according to 2007 diagnostic criteria of The American Thoracic Society (ATS). To investigate the deficiencies of complement, C4A and C4B gene copy numbers and phenotype frequencies of the C4 allotypes were analyzed. Unselected, healthy, 149 Finnish adults were used as controls. NTM patients had more often C4 deficiencies (C4A or C4B) than controls (36/50 [72%] vs 83/149 [56%], OR = 2.05, 95%CI = 1.019-4.105, p = 0.042). C4 deficiencies for female NTM patients were more common than for controls (29/36 [81%] vs 55/100 [55%], OR = 3.39, 95% CI = 1.358-8.460, p = 0.007). C4 deficiences seemed not to be related to any specific underlying disease or C4 phenotype. C4 deficiency may be a risk factor for NTM infection in especially elderly female patients.

All five host-range variants of Xanthomonas citri carry one pthA homolog with 17.5 repeats that determines pathogenicity on citrus, but none determine host-range variation.

PubMed

Al-Saadi, Abdulwahid; Reddy, Joseph D; Duan, Yong P; Brunings, Asha M; Yuan, Qiaoping; Gabriel, Dean W

2007-08-01

Citrus canker disease is caused by five groups of Xanthomonas citri strains that are distinguished primarily by host range: three from Asia (A, A*, and A(w)) and two that form a phylogenetically distinct clade and originated in South America (B and C). Every X. citri strain carries multiple DNA fragments that hybridize with pthA, which is essential for the pathogenicity of wide-host-range X. citri group A strain 3213. DNA fragments that hybridized with pthA were cloned from a representative strain from all five groups. Each strain carried one and only one pthA homolog that functionally complemented a knockout mutation of pthA in 3213. Every complementing homolog was of identical size to pthA and carried 17.5 nearly identical, direct tandem repeats, including three new genes from narrow-host-range groups C (pthC), A(w) (pthAW), and A* (pthA*). Every noncomplementing paralog was of a different size; one of these was sequenced from group A* (pthA*-2) and was found to have an intact promoter and full-length reading frame but with 15.5 repeats. None of the complementing homologs nor any of the noncomplementing paralogs conferred avirulence to 3213 on grapefruit or suppressed avirulence of a group A* strain on grapefruit. A knockout mutation of pthC in a group C strain resulted in loss of pathogenicity on lime, but the strain was unaffected in ability to elicit an HR on grapefruit. This pthC- mutant was fully complemented by pthA, pthB, or pthC. Analysis of the predicted amino-acid sequences of all functional pthA homologs and nonfunctional paralogs indicated that the specific sequence of the 17th repeat may be essential for pathogenicity of X. citri on citrus.

High-Mobility Group Box 1-Induced Complement Activation Causes Sterile Inflammation.

PubMed

Kim, Sook Young; Son, Myoungsun; Lee, Sang Eun; Park, In Ho; Kwak, Man Sup; Han, Myeonggil; Lee, Hyun Sook; Kim, Eun Sook; Kim, Jae-Young; Lee, Jong Eun; Choi, Ji Eun; Diamond, Betty; Shin, Jeon-Soo

2018-01-01

High-mobility group box 1 (HMGB1), a well-known danger-associated molecular pattern molecule, acts as a pro-inflammatory molecule when secreted by activated immune cells or released after necrotic cell damage. HMGB1 binds to immunogenic bacterial components and augments septic inflammation. In this study, we show how HMGB1 mediates complement activation, promoting sterile inflammation. We show that HMGB1 activates the classical pathway of complement system in an antibody-independent manner after binding to C1q. The C3a complement activation product in human plasma and C5b-9 membrane attack complexes on cell membrane surface are detected after the addition of HMGB1. In an acetaminophen (APAP)-induced hepatotoxicity model, APAP injection reduced HMGB1 levels and elevated C3 levels in C1q-deficient mouse serum samples, compared to that in wild-type (WT) mice. APAP-induced C3 consumption was inhibited by sRAGE treatment in WT mice. Moreover, in a mouse model of brain ischemia-reperfusion injury based on middle cerebral arterial occlusion, C5b-9 complexes were deposited on vessels where HMGB1 was accumulated, an effect that was suppressed upon HMGB1 neutralization. We propose that the HMGB1 released after cell necrosis and in ischemic condition can trigger the classical pathway of complement activation to exacerbate sterile inflammation.

High-Mobility Group Box 1-Induced Complement Activation Causes Sterile Inflammation

PubMed Central

Kim, Sook Young; Son, Myoungsun; Lee, Sang Eun; Park, In Ho; Kwak, Man Sup; Han, Myeonggil; Lee, Hyun Sook; Kim, Eun Sook; Kim, Jae-Young; Lee, Jong Eun; Choi, Ji Eun; Diamond, Betty; Shin, Jeon-Soo

2018-01-01

High-mobility group box 1 (HMGB1), a well-known danger-associated molecular pattern molecule, acts as a pro-inflammatory molecule when secreted by activated immune cells or released after necrotic cell damage. HMGB1 binds to immunogenic bacterial components and augments septic inflammation. In this study, we show how HMGB1 mediates complement activation, promoting sterile inflammation. We show that HMGB1 activates the classical pathway of complement system in an antibody-independent manner after binding to C1q. The C3a complement activation product in human plasma and C5b-9 membrane attack complexes on cell membrane surface are detected after the addition of HMGB1. In an acetaminophen (APAP)-induced hepatotoxicity model, APAP injection reduced HMGB1 levels and elevated C3 levels in C1q-deficient mouse serum samples, compared to that in wild-type (WT) mice. APAP-induced C3 consumption was inhibited by sRAGE treatment in WT mice. Moreover, in a mouse model of brain ischemia–reperfusion injury based on middle cerebral arterial occlusion, C5b-9 complexes were deposited on vessels where HMGB1 was accumulated, an effect that was suppressed upon HMGB1 neutralization. We propose that the HMGB1 released after cell necrosis and in ischemic condition can trigger the classical pathway of complement activation to exacerbate sterile inflammation. PMID:29696019

Studies of Dynamic Protein-Protein Interactions in Bacteria Using Renilla Luciferase Complementation Are Undermined by Nonspecific Enzyme Inhibition

PubMed Central

Hatzios, Stavroula K.; Ringgaard, Simon; Davis, Brigid M.; Waldor, Matthew K.

2012-01-01

The luciferase protein fragment complementation assay is a powerful tool for studying protein-protein interactions. Two inactive fragments of luciferase are genetically fused to interacting proteins, and when these two proteins interact, the luciferase fragments can reversibly associate and reconstitute enzyme activity. Though this technology has been used extensively in live eukaryotic cells, split luciferase complementation has not yet been applied to studies of dynamic protein-protein interactions in live bacteria. As proof of concept and to develop a new tool for studies of bacterial chemotaxis, fragments of Renilla luciferase (Rluc) were fused to the chemotaxis-associated response regulator CheY3 and its phosphatase CheZ in the enteric pathogen Vibrio cholerae. Luciferase activity was dependent on the presence of both CheY3 and CheZ fusion proteins, demonstrating the specificity of the assay. Furthermore, enzyme activity was markedly reduced in V. cholerae chemotaxis mutants, suggesting that this approach can measure defects in chemotactic signaling. However, attempts to measure changes in dynamic CheY3-CheZ interactions in response to various chemoeffectors were undermined by nonspecific inhibition of the full-length luciferase. These observations reveal an unexpected limitation of split Rluc complementation that may have implications for existing data and highlight the need for great caution when evaluating small molecule effects on dynamic protein-protein interactions using the split luciferase technology. PMID:22905225

Studies of dynamic protein-protein interactions in bacteria using Renilla luciferase complementation are undermined by nonspecific enzyme inhibition.

PubMed

Hatzios, Stavroula K; Ringgaard, Simon; Davis, Brigid M; Waldor, Matthew K

2012-01-01

The luciferase protein fragment complementation assay is a powerful tool for studying protein-protein interactions. Two inactive fragments of luciferase are genetically fused to interacting proteins, and when these two proteins interact, the luciferase fragments can reversibly associate and reconstitute enzyme activity. Though this technology has been used extensively in live eukaryotic cells, split luciferase complementation has not yet been applied to studies of dynamic protein-protein interactions in live bacteria. As proof of concept and to develop a new tool for studies of bacterial chemotaxis, fragments of Renilla luciferase (Rluc) were fused to the chemotaxis-associated response regulator CheY3 and its phosphatase CheZ in the enteric pathogen Vibrio cholerae. Luciferase activity was dependent on the presence of both CheY3 and CheZ fusion proteins, demonstrating the specificity of the assay. Furthermore, enzyme activity was markedly reduced in V. cholerae chemotaxis mutants, suggesting that this approach can measure defects in chemotactic signaling. However, attempts to measure changes in dynamic CheY3-CheZ interactions in response to various chemoeffectors were undermined by nonspecific inhibition of the full-length luciferase. These observations reveal an unexpected limitation of split Rluc complementation that may have implications for existing data and highlight the need for great caution when evaluating small molecule effects on dynamic protein-protein interactions using the split luciferase technology.

Molecular Imaging of Phosphorylation Events for Drug Development

PubMed Central

Chan, C. T.; Paulmurugan, R.; Reeves, R. E.; Solow-Cordero, D.; Gambhir, S. S.

2014-01-01

Purpose Protein phosphorylation mediated by protein kinases controls numerous cellular processes. A genetically encoded, generalizable split firefly luciferase (FL)-assisted complementation system was developed for noninvasive monitoring phosphorylation events and efficacies of kinase inhibitors in cell culture and in small living subjects by optical bioluminescence imaging. Procedures An Akt sensor (AST) was constructed to monitor Akt phosphorylation and the effect of different PI-3K and Akt inhibitors. Specificity of AST was determined using a non-phosphorylable mutant sensor containing an alanine substitution (ASA). Results The PI-3K inhibitor LY294002 and Akt kinase inhibitor perifosine led to temporal- and dose-dependent increases in complemented FL activities in 293T human kidney cancer cells stably expressing AST (293T/AST) but not in 293T/ASA cells. Inhibition of endogenous Akt phosphorylation and kinase activities by perifosine also correlated with increase in complemented FL activities in 293T/AST cells but not in 293T/ASA cells. Treatment of nude mice bearing 293T/AST xenografts with perifosine led to a 2-fold increase in complemented FL activities compared to that of 293T/ASA xenografts. Our system was used to screen a small chemical library for novel modulators of Akt kinase activity. Conclusion This generalizable approach for noninvasive monitoring of phosphorylation events will accelerate the discovery and validation of novel kinase inhibitors and modulators of phosphorylation events. PMID:19048345

Glucose-6-Phosphate Dehydrogenase Deficiency Mimicking Atypical Hemolytic Uremic Syndrome.

PubMed

Walsh, Patrick R; Johnson, Sally; Brocklebank, Vicky; Salvatore, Jacobo; Christian, Martin; Kavanagh, David

2018-02-01

A 4-year-old boy presented with nonimmune hemolysis, thrombocytopenia, and acute kidney injury. Investigations for an underlying cause failed to identify a definitive cause and a putative diagnosis of complement-mediated atypical hemolytic uremic syndrome (aHUS) was made. The patient was started initially on plasma exchange and subsequently eculizumab therapy, after which his kidney function rapidly improved. While on eculizumab therapy, despite adequate complement blockade, he presented 2 more times with hemolytic anemia and thrombocytopenia, but without renal involvement. Genetic analysis did not uncover a mutation in any known aHUS gene (CFH, CFI, CFB, C3, CD46, THBD, INF2, and DGKE) and anti-factor H antibodies were undetectable. Whole-exome sequencing was undertaken to identify a cause for the eculizumab resistance. This revealed a pathogenic variant in G6PD (glucose-6-phosphate dehydrogenase), which was confirmed by functional analysis demonstrating decreased erythrocyte G6PD activity. Eculizumab therapy was withdrawn. Complement-mediated aHUS is a diagnosis of exclusion and this case highlights the diagnostic difficulty that remains without an immediately available biomarker for confirmation. This case of G6PD deficiency presented with a phenotype clinically indistinguishable from complement-mediated aHUS. We recommend that G6PD deficiency be included in the differential diagnosis of patients presenting with aHUS and suggest measuring erythrocyte G6PD concentrations in these patients. Copyright © 2017. Published by Elsevier Inc.

Isolation and Characterization of Sex-Linked Female-Sterile Mutants in DROSOPHILA MELANOGASTER

PubMed Central

Gans, Madeleine; Audit, Claudie; Masson, Michele

1975-01-01

The purpose of the experiments described was to identify X chromosome genes functioning mainly or exclusively during oogenesis. Two mutagenesis experiments were carried out with ethyl methane sulfonate. Following treatment inducing 60% lethals, 9% of the treated X chromosomes carried a female sterility mutation which did not otherwise seriously affect viability. Among —95 isolated mutants, 19 were heat-sensitive and 5 cold-sensitive. The mutants have been classified as follows: I (16 mutants; 12 complementation groups): the females laid few or no eggs; the defect concerned either ovulation or oogenesis. II (37 mutants; 18 complementation groups): the female laid morphologically abnormal eggs, often with increased membrane permeability. III A (13 mutants; at least 8 complementation groups): the homozygous females were sterile if mated to mutant males; their progeny (homo- and hemizygous) died at a late embryonic stage (11 mutants), at the larval stage (1 mutant) or at the pupal stage (1 mutant). However fertility was partly restored by breeding to wild-type males as shown by survival of some heterozygous descendants. III B (29 mutants; 22 complementation groups): the fertility of the females was not restored by breeding to a wild-type male. Most of the eggs of 13 of the mutants died at a late stage of embryogenesis. The eggs of the others ceased development earlier or, perhaps, remained unfertilized. The distribution of the number of mutants per complementation group led to an estimation of a total of about 150 X-linked genes involved in female fertility. The females of three mutants, heat-sensitive and totally sterile at 29°, produced at a lower temperature descendants morphologically abnormal or deprived of germ cells. Three other mutants not described in detail showed a reduction in female fertility with many descendants lacking germ cells. A desirable mutant which was not recovered was one with normal fertile females producing descendants which, regardless of their genotype, bore specific morphological abnormalities. The value of the mutants isolated for analysis of the complex processes leading to egg formation and initiation of development is discussed. PMID:814037

Mammalian synthetic biology for studying the cell

PubMed Central

Mathur, Melina; Xiang, Joy S.

2017-01-01

Synthetic biology is advancing the design of genetic devices that enable the study of cellular and molecular biology in mammalian cells. These genetic devices use diverse regulatory mechanisms to both examine cellular processes and achieve precise and dynamic control of cellular phenotype. Synthetic biology tools provide novel functionality to complement the examination of natural cell systems, including engineered molecules with specific activities and model systems that mimic complex regulatory processes. Continued development of quantitative standards and computational tools will expand capacities to probe cellular mechanisms with genetic devices to achieve a more comprehensive understanding of the cell. In this study, we review synthetic biology tools that are being applied to effectively investigate diverse cellular processes, regulatory networks, and multicellular interactions. We also discuss current challenges and future developments in the field that may transform the types of investigation possible in cell biology. PMID:27932576

Emerging from the bottleneck: benefits of the comparative approach to modern neuroscience.

PubMed

Brenowitz, Eliot A; Zakon, Harold H

2015-05-01

Neuroscience has historically exploited a wide diversity of animal taxa. Recently, however, research has focused increasingly on a few model species. This trend has accelerated with the genetic revolution, as genomic sequences and genetic tools became available for a few species, which formed a bottleneck. This coalescence on a small set of model species comes with several costs that are often not considered, especially in the current drive to use mice explicitly as models for human diseases. Comparative studies of strategically chosen non-model species can complement model species research and yield more rigorous studies. As genetic sequences and tools become available for many more species, we are poised to emerge from the bottleneck and once again exploit the rich biological diversity offered by comparative studies. Copyright © 2015 Elsevier Ltd. All rights reserved.

A Knowledge Base for Teaching Biology Situated in the Context of Genetic Testing

NASA Astrophysics Data System (ADS)

van der Zande, Paul; Waarlo, Arend Jan; Brekelmans, Mieke; Akkerman, Sanne F.; Vermunt, Jan D.

2011-10-01

Recent developments in the field of genomics will impact the daily practice of biology teachers who teach genetics in secondary education. This study reports on the first results of a research project aimed at enhancing biology teacher knowledge for teaching genetics in the context of genetic testing. The increasing body of scientific knowledge concerning genetic testing and the related consequences for decision-making indicate the societal relevance of such a situated learning approach. What content knowledge do biology teachers need for teaching genetics in the personal health context of genetic testing? This study describes the required content knowledge by exploring the educational practice and clinical genetic practices. Nine experienced teachers and 12 respondents representing the clinical genetic practices (clients, medical professionals, and medical ethicists) were interviewed about the biological concepts and ethical, legal, and social aspects (ELSA) of testing they considered relevant to empowering students as future health care clients. The ELSA suggested by the respondents were complemented by suggestions found in the literature on genetic counselling. The findings revealed that the required teacher knowledge consists of multiple layers that are embedded in specific genetic test situations: on the one hand, the knowledge of concepts represented by the curricular framework and some additional concepts (e.g. multifactorial and polygenic disorder) and, on the other hand, more knowledge of ELSA and generic characteristics of genetic test practice (uncertainty, complexity, probability, and morality). Suggestions regarding how to translate these characteristics, concepts, and ELSA into context-based genetics education are discussed.

O1.6. INCREASED COMPLEMENT FACTORS C3 AND C4 IN SCHIZOPHRENIA AND THE EARLY STAGES OF PSYCHOSIS: IMPLICATIONS FOR CLINICAL SYMPTOMATOLOGY AND CORTICAL THICKNESS

PubMed Central

Cropley, Vanessa; Laskaris, Liliana; Zalesky, Andrew; Weickert, Cynthia Shannon; Biase, Maria Di; Chana, Gursharan; Baune, Bernhard; Bousman, Chad; Nelson, Barnaby; McGorry, Patrick D; Everall, Ian; Pantelis, Christos

2018-01-01

Abstract Background The complement system - a key component of the innate immune system, has been proposed to contribute to the pathogenesis of schizophrenia. Recently, complement C4 was associated with increased risk of schizophrenia, and in a mouse model, developmentally-timed synaptic pruning. These observations have led to proposals that abnormal activation of the complement system might contribute to the development of schizophrenia by disrupting synaptic pruning during key developmental periods. However, despite renewed interest in the complement system in schizophrenia it remains unclear whether peripheral complement levels differ in cases compared to controls, change over the course of illness and whether they are associated with current symptomatology and brain cortical thickness. This study aimed to: i) investigate whether peripheral complement protein levels are altered at different stages of illness, and ii) identify patterns among complement protein levels that predict clinical symptoms and grey matter thickness across the cortex. Methods Complement factors C1q, C3 and C4 were quantified in 183 participants [n=83 Healthy Controls (HC), n=10 Ultra-High Risk (UHR) for psychosis, n=40 First Episode Psychosis (FEP), n=50 Chronic schizophrenia] using Multiplex ELISA. Permutation-based t-tests were used to assess between-group differences in complement protein levels at each of the three illness stages, relative to age- and gender-matched healthy controls. Canonical correlation analysis was used to identify patterns of complement protein levels that correlated with clinical symptoms and regional thickness across the cortex. Results C3 and C4 were significantly increased in FEP and UHR patients, whereas only C4 was significantly increased in chronic patients. A molecular pattern of increased C4 and decreased C3 was associated with positive and negative symptom severity in the pooled patient sample. Increased C4 levels alone, or decreased C3 levels alone, did not correlate with symptom severity as strongly as the pattern of increased C4 in combination with decreased C3. Preliminary canonical correlation analyses revealed that, in healthy controls, a molecular pattern characterised by increased C3 and decreased C4 was associated with relatively thinner paracentral, inferior parietal and inferior temporal cortices, but relatively thicker insular, in the left hemisphere. In the pooled patient group, a trend for increased C3 in combination with decreased C1q was associated with relatively thinner left lateral occipital cortex and pars orbitalis but relatively thicker pars opercularis and precuneus. Discussion Our findings indicate that peripheral complement concentration is particularly increased early and preceding psychosis and its imbalance may be associated with symptom severity and variation in regional grey matter thickness across the cortex.

A linkage map for the B-genome of Arachis (Fabaceae) and its synteny to the A-genome

PubMed Central

Moretzsohn, Márcio C; Barbosa, Andrea VG; Alves-Freitas, Dione MT; Teixeira, Cristiane; Leal-Bertioli, Soraya CM; Guimarães, Patrícia M; Pereira, Rinaldo W; Lopes, Catalina R; Cavallari, Marcelo M; Valls, José FM; Bertioli, David J; Gimenes, Marcos A

2009-01-01

Background Arachis hypogaea (peanut) is an important crop worldwide, being mostly used for edible oil production, direct consumption and animal feed. Cultivated peanut is an allotetraploid species with two different genome components, A and B. Genetic linkage maps can greatly assist molecular breeding and genomic studies. However, the development of linkage maps for A. hypogaea is difficult because it has very low levels of polymorphism. This can be overcome by the utilization of wild species of Arachis, which present the A- and B-genomes in the diploid state, and show high levels of genetic variability. Results In this work, we constructed a B-genome linkage map, which will complement the previously published map for the A-genome of Arachis, and produced an entire framework for the tetraploid genome. This map is based on an F2 population of 93 individuals obtained from the cross between the diploid A. ipaënsis (K30076) and the closely related A. magna (K30097), the former species being the most probable B genome donor to cultivated peanut. In spite of being classified as different species, the parents showed high crossability and relatively low polymorphism (22.3%), compared to other interspecific crosses. The map has 10 linkage groups, with 149 loci spanning a total map distance of 1,294 cM. The microsatellite markers utilized, developed for other Arachis species, showed high transferability (81.7%). Segregation distortion was 21.5%. This B-genome map was compared to the A-genome map using 51 common markers, revealing a high degree of synteny between both genomes. Conclusion The development of genetic maps for Arachis diploid wild species with A- and B-genomes effectively provides a genetic map for the tetraploid cultivated peanut in two separate diploid components and is a significant advance towards the construction of a transferable reference map for Arachis. Additionally, we were able to identify affinities of some Arachis linkage groups with Medicago truncatula, which will allow the transfer of information from the nearly-complete genome sequences of this model legume to the peanut crop. PMID:19351409

Genetic diagnosis of X-linked dominant hypophosphatemic rickets in a cohort study: Tubular reabsorption of phosphate and 1,25(OH)2D serum levels are associated with PHEX mutation type

PubMed Central

2011-01-01

Background Genetic Hypophosphatemic Rickets (HR) is a group of diseases characterized by renal phosphate wasting with inappropriately low or normal 1,25-dihydroxyvitamin D3 (1,25(OH)2D) serum levels. The most common form of HR is X-linked dominant HR (XLHR) which is caused by inactivating mutations in the PHEX gene. The purpose of this study was to perform genetic diagnosis in a cohort of patients with clinical diagnosis of HR, to perform genotype-phenotype correlations of those patients and to compare our data with other HR cohort studies. Methods Forty three affected individuals from 36 non related families were analyzed. For the genetic analysis, the PHEX gene was sequenced in all of the patients and in 13 cases the study was complemented by mRNA sequencing and Multiple Ligation Probe Assay. For the genotype-phenotype correlation study, the clinical and biochemical phenotype of the patients was compared with the type of mutation, which was grouped into clearly deleterious or likely causative, using the Mann-Whitney and Fisher's exact test. Results Mutations in the PHEX gene were identified in all the patients thus confirming an XLHR. Thirty four different mutations were found distributed throughout the gene with higher density at the 3' end. The majority of the mutations were novel (69.4%), most of them resulted in a truncated PHEX protein (83.3%) and were family specific (88.9%). Tubular reabsorption of phosphate (TRP) and 1,25(OH)2D serum levels were significantly lower in patients carrying clearly deleterious mutations than in patients carrying likely causative ones (61.39 ± 19.76 vs. 80.14 ± 8.80%, p = 0.028 and 40.93 ± 30.73 vs. 78.46 ± 36.27 pg/ml, p = 0.013). Conclusions PHEX gene mutations were found in all the HR cases analyzed, which was in contrast with other cohort studies. Patients with clearly deleterious PHEX mutations had lower TRP and 1,25(OH)2D levels suggesting that the PHEX type of mutation might predict the XLHR phenotype severity. PMID:21902834

Role of Complement in a Rat Model of Paclitaxel-Induced Peripheral Neuropathy.

PubMed

Xu, Jijun; Zhang, Lingjun; Xie, Mian; Li, Yan; Huang, Ping; Saunders, Thomas L; Fox, David A; Rosenquist, Richard; Lin, Feng

2018-06-15

Chemotherapy-induced peripheral neuropathy (CIPN) is a painful and debilitating side effect of cancer chemotherapy with an unclear pathogenesis. Consequently, the available therapies for this neuropathic pain syndrome are inadequate, leading to a significantly reduced quality of life in many patients. Complement, a key component of the innate immune system, has been associated with neuroinflammation, a potentially important trigger of some types of neuropathic pain. However, the role of complement in CIPN remains unclear. To address this issue, we developed a C3 knockout (KO) rat model and induced CIPN in these KO rats and wild-type littermates via the i.p. administration of paclitaxel, a chemotherapeutic agent associated with CIPN. We then compared the severity of mechanical allodynia, complement activation, and intradermal nerve fiber loss between the groups. We found that 1) i.p. paclitaxel administration activated complement in wild-type rats, 2) paclitaxel-induced mechanical allodynia was significantly reduced in C3 KO rats, and 3) the paclitaxel-induced loss of intradermal nerve fibers was markedly attenuated in C3 KO rats. In in vitro studies, we found that paclitaxel-treated rat neuronal cells activated complement, leading to cellular injury. Our findings demonstrate a previously unknown but pivotal role of complement in CIPN and suggest that complement may be a new target for the development of novel therapeutics to manage this painful disease. Copyright © 2018 by The American Association of Immunologists, Inc.

Complement factor H-related proteins in IgA nephropathy-sometimes a gentle nudge does the trick.

PubMed

Thurman, Joshua M; Laskowski, Jennifer

2017-10-01

Complement activation probably contributes to glomerular inflammation and damage in IgA nephropathy. In this issue, 2 groups report that levels of factor H-related protein 1 are elevated in patients with IgA nephropathy and correlate with disease progression. These studies provide new evidence that the complement cascade is important to the pathogenesis of this disease. These results also suggest that factor H-related protein 1 levels may be useful for identifying those patients at high risk of disease progression. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

Perspectives of non-Hispanic Black and Latino patients in Boston's urban community health centers on their experiences with diabetes and hypertension.

PubMed

Russell, Beverley E; Gurrola, Edith; Ndumele, Chima D; Landon, Bruce E; O'Malley, James A; Keegan, Tom; Ayanian, John Z; Hicks, Leroi S

2010-06-01

Racial/ethnic disparities exist in the prevalence and outcomes of diabetes and hypertension in the U.S. A better understanding of the health beliefs and experiences of non-Hispanic Blacks and Latinos with these diseases could help to improve their care outcomes. We conducted eight focus groups stratified by participants' race/ethnicity, with 34 non-Hispanic Blacks and Latinos receiving care for diabetes and/or hypertension in one of 7 community health centers in Boston. Focus groups were designed to determine participants' levels of understanding about their chronic illness, assess their barriers to the management of their illness, and inquire about interventions they considered may help achieve better health outcomes. Among both groups of participants, nutrition (traditional diets), genetics and environmental stress (e.g. neighborhood crime and poor conditions) were described as primary contributors to diabetes and hypertension. Unhealthy diets were reported as being a major barrier to disease management. Participants also believed that they would benefit from attending groups on management and education for their conditions that include creative ways to adopt healthy foods that complement their ethnic diets, exercise opportunities, and advice on how to prevent disease manifestation among family members. Interactive discussion groups focused on lifestyle modification and disease management should be created for patients to learn more about their diseases. Future research evaluating the effectiveness of interactive diabetes and hypertension groups that apply patient racial/ethnic traditions should be considered.

A second generation genetic linkage map of Japanese flounder (Paralichthys olivaceus)

PubMed Central

2010-01-01

Background Japanese flounder (Paralichthys olivaceus) is one of the most economically important marine species in Northeast Asia. Information on genetic markers associated with quantitative trait loci (QTL) can be used in breeding programs to identify and select individuals carrying desired traits. Commercial production of Japanese flounder could be increased by developing disease-resistant fish and improving commercially important traits. Previous maps have been constructed with AFLP markers and a limited number of microsatellite markers. In this study, improved genetic linkage maps are presented. In contrast with previous studies, these maps were built mainly with a large number of codominant markers so they can potentially be used to analyze different families and populations. Results Sex-specific genetic linkage maps were constructed for the Japanese flounder including a total of 1,375 markers [1,268 microsatellites, 105 single nucleotide polymorphisms (SNPs) and two genes]; 1,167 markers are linked to the male map and 1,067 markers are linked to the female map. The lengths of the male and female maps are 1,147.7 cM and 833.8 cM, respectively. Based on estimations of map lengths, the female and male maps covered 79 and 82% of the genome, respectively. Recombination ratio in the new maps revealed F:M of 1:0.7. All linkage groups in the maps presented large differences in the location of sex-specific recombination hot-spots. Conclusions The improved genetic linkage maps are very useful for QTL analyses and marker-assisted selection (MAS) breeding programs for economically important traits in Japanese flounder. In addition, SNP flanking sequences were blasted against Tetraodon nigroviridis (puffer fish) and Danio rerio (zebrafish), and synteny analysis has been carried out. The ability to detect synteny among species or genera based on homology analysis of SNP flanking sequences may provide opportunities to complement initial QTL experiments with candidate gene approaches from homologous chromosomal locations identified in related model organisms. PMID:20937088

Identifying genome-wide immune gene variation underlying infectious disease in wildlife populations - a next generation sequencing approach in the gopher tortoise.

PubMed

Elbers, Jean P; Brown, Mary B; Taylor, Sabrina S

2018-01-19

Infectious disease is the single greatest threat to taxa such as amphibians (chytrid fungus), bats (white nose syndrome), Tasmanian devils (devil facial tumor disease), and black-footed ferrets (canine distemper virus, plague). Although understanding the genetic basis to disease susceptibility is important for the long-term persistence of these groups, most research has been limited to major-histocompatibility and Toll-like receptor genes. To better understand the genetic basis of infectious disease susceptibility in a species of conservation concern, we sequenced all known/predicted immune response genes (i.e., the immunomes) in 16 Florida gopher tortoises, Gopherus polyphemus. All tortoises produced antibodies against Mycoplasma agassizii (an etiologic agent of infectious upper respiratory tract disease; URTD) and, at the time of sampling, either had (n = 10) or lacked (n = 6) clinical signs. We found several variants associated with URTD clinical status in complement and lectin genes, which may play a role in Mycoplasma immunity. Thirty-five genes deviated from neutrality according to Tajima's D. These genes were enriched in functions relating to macromolecule and protein modifications, which are vital to immune system functioning. These results are suggestive of genetic differences that might contribute to disease severity, a finding that is consistent with other mycoplasmal diseases. This has implications for management because tortoises across their range may possess genetic variation associated with a more severe response to URTD. More generally: 1) this approach demonstrates that a broader consideration of immune genes is better able to identify important variants, and; 2) this data pipeline can be adopted to identify alleles associated with disease susceptibility or resistance in other taxa, and therefore provide information on a population's risk of succumbing to disease, inform translocations to increase genetic variation for disease resistance, and help to identify potential treatments.

Pathogenesis of Group A Streptococcal Infections

PubMed Central

Cunningham, Madeleine W.

2000-01-01

Group A streptococci are model extracellular gram-positive pathogens responsible for pharyngitis, impetigo, rheumatic fever, and acute glomerulonephritis. A resurgence of invasive streptococcal diseases and rheumatic fever has appeared in outbreaks over the past 10 years, with a predominant M1 serotype as well as others identified with the outbreaks. emm (M protein) gene sequencing has changed serotyping, and new virulence genes and new virulence regulatory networks have been defined. The emm gene superfamily has expanded to include antiphagocytic molecules and immunoglobulin-binding proteins with common structural features. At least nine superantigens have been characterized, all of which may contribute to toxic streptococcal syndrome. An emerging theme is the dichotomy between skin and throat strains in their epidemiology and genetic makeup. Eleven adhesins have been reported, and surface plasmin-binding proteins have been defined. The strong resistance of the group A streptococcus to phagocytosis is related to factor H and fibrinogen binding by M protein and to disarming complement component C5a by the C5a peptidase. Molecular mimicry appears to play a role in autoimmune mechanisms involved in rheumatic fever, while nephritis strain-associated proteins may lead to immune-mediated acute glomerulonephritis. Vaccine strategies have focused on recombinant M protein and C5a peptidase vaccines, and mucosal vaccine delivery systems are under investigation. PMID:10885988

Evaluation of lectin pathway activity and mannan-binding lectin levels in the course of pregnancy complicated by diabetes type 1, based on the genetic background.

PubMed

Pertyńska Marczewska, Magdalena; Cedzyński, Maciej; Swierzko, Anna; Szala, Agnieszka; Sobczak, Małgorzata; Cypryk, Katarzyna; Wilczyński, Jan

2009-01-01

There are numerous indications that either mannan-binding lectin (MBL) deficiency or its excessive activity are associated with adverse pregnancy outcomes. High MBL concentrations and corresponding MBL2 genotypes were shown to be associated with microvascular complications in type 1 diabetes. The aim of this study was to evaluate levels of MBL and MBL-dependent activity of the lectin pathway (LP) of complement in the course of pregnancy in diabetic mothers, based on genetic background. These parameters were determined in samples from healthy non-pregnant (control), diabetic non-pregnant, healthy pregnant, and pregnant diabetic women. No significant differences in median MBL levels or LP activities were found in any study group compared to the control. However, statistically significant differences in MBL levels were noted during pregnancy between the 1st and 3rd trimesters in both healthy controls and pregnant diabetics. With regard to LP values, similar trends were evident, but statistically significant results were obtained only in the healthy pregnant group. When data analysis was confined to patients carrying the A/A (wild-type) MBL2 genotype, an increase in MBL level during pregnancy (in both healthy and diabetic pregnant women) was still observed. Similarly, LP activity increased during both healthy and diabetic pregnancies, significantly so for the former. Diabetes, an autoimmune disease, is a serious complication of pregnancy. Therefore, determination of MBL status might be beneficial in identifying type 1 diabetic patients who are at increased risk of developing both vascular complications and poor pregnancy outcomes.

Cliona acephala (Porifera: Demospongiae: Clionaida), a new encrusting excavating reef sponge from the Colombian Caribbean belonging to the Cliona viridis species complex.

PubMed

Zea, Sven; López-Victoria, Mateo

2016-10-26

Several groups of sponges are able to excavate galleries and tunnels in calcareous substrata such as limestone rock, shells, calcareous algae and coral skeletons. Within the genus Cliona, some species share the common traits of being brown to olive-green in color, and harboring photosynthetic, unicellular dinoflagellates (zooxanthellae). These Cliona spp. have been grouped as the Cliona viridis species complex. Several species of this complex completely encrust the excavated substratum with a thin veneer of tissue and, when colonizing dead exposed parts of live coral colonies, they are able to undermine or overgrow and thus kill live coral tissue as they advance predominantly laterally. In the course of our taxonomic and ecological studies of Caribbean brown to brown-black encrusting Cliona, we found an as yet undescribed species that stands out by having tylostyle megasclere spicules with narrow heads and lacking the usual microsclere spicule complement of spirasters. This species, named and described here Cliona acephala n. sp., has so far been found exclusively in the Santa Marta area, Caribbean coast of Colombia. Previous studies with ITS2 ribosomal DNA showed it to be genetically distinct from other Caribbean encrusting species belonging to the Cliona viridis species complex, vis. Cliona aprica, Cliona caribbaea, Cliona tenuis and Cliona varians, but making it genetically closer to Indo-Pacific Cliona orientalis. An intriguing possibility, to be addressed with further studies, is that C. acephala n. sp. may have been introduced to the Caribbean. However, until proved otherwise, we regard the material presently described as distinct.

Gene signature in Alzheimer's disease and environmental factors: the virus chronicle.

PubMed

Licastro, Federico; Carbone, Ilaria; Ianni, Manuela; Porcellini, Elisa

2011-01-01

Genome wide association investigations from large cohorts of patients with Alzheimer's disease (AD) and non demented controls (CTR) showed that a limited set of genes were associated (p > 10-5) with the disease. A very recent study from our group showed that an additional limited group of SNP in selected genes were associated with AD. In this report we argue that the association of these genes with AD is suggestive of a pivotal role of environmental factors in the pathogenesis of the disease and one of these factors is virus infection. In other words, the genetic signature revealed by genome wide association (GWA) studies discloses a network of genes that might influence the ability of the central nervous system to cope with and fight against the invasion by virus of the herpes family. In fact, Nectin-2 (NC-2); apolipoprotein E (APOE); glycoprotein carcinoembryonic antigen related cell adhesion molecule-16 (CEACAM-16); B-cell lymphoma-3 (Bcl-3); translocase of outer mitochondrial membrane 40 homolog (T0MM-40); complement receptor-1 (CR-l); APOJ or clusterin and C-type lectin domain A family-16 member (CLEC-16A); Phosphatidyl inositol- binding clathrin assembly protein gene (PICALM); ATP-bonding cassette, sub family A, member 7 (ABCA7); membrane spanning A4 (MSA4); CD2 associated protein (CD2AP); cluster of differentiation 33 (CD33); and ephrin receptor A1 (EPHA1) result in a genetic signature that might affect individual brain susceptibility to infection by the herpes virus family during aging, leading to neuronal loss, inflammation, and amyloid deposition.

Social complementation and growth advantages promote socially defective bacterial isolates.

PubMed

Kraemer, Susanne A; Velicer, Gregory J

2014-04-22

Social interactions among diverse individuals that encounter one another in nature have often been studied among animals but rarely among microbes. For example, the evolutionary forces that determine natural frequencies of bacteria that express cooperative behaviours at low levels remain poorly understood. Natural isolates of the soil bacterium Myxococcus xanthus sampled from the same fruiting body often vary in social phenotypes, such as group swarming and multicellular development. Here, we tested whether genotypes highly proficient at swarming or development might promote the persistence of less socially proficient genotypes from the same fruiting body. Fast-swarming strains complemented slower isolates, allowing the latter to keep pace with faster strains in mixed groups. During development, one low-sporulating strain was antagonized by high sporulators, whereas others with severe developmental defects had those defects partially complemented by high-sporulating strains. Despite declining in frequency overall during competition experiments spanning multiple cycles of development, developmentally defective strains exhibited advantages during the growth phases of competitions. These results suggest that microbes with low-sociality phenotypes often benefit from interacting with more socially proficient strains. Such complementation may combine with advantages at other traits to increase equilibrium frequencies of low-sociality genotypes in natural populations.

Complement inhibition prevents gut ischemia and endothelial cell dysfunction after hemorrhage/resuscitation.

PubMed

Fruchterman, T M; Spain, D A; Wilson, M A; Harris, P D; Garrison, R N

1998-10-01

Complement, a nonspecific immune response, is activated during hemorrhage/resuscitation (HEM/RES) and is involved in cellular damage. We hypothesized that activated complement injures endothelial cells (ETCs) and is responsible for intestinal microvascular hypoperfusion after HEM/RES. Four groups of rats were studied by in vivo videomicroscopy of the intestine: SHAM, HEM/RES, HEM/RES + sCR1 (complement inhibitor, 15 mg/kg intravenously given before resuscitation), and SHAM + sCR1. Hemorrhage was to 50% of mean arterial pressure for 60 minutes followed by resuscitation with shed blood plus an equal volume of saline. ETC function was assessed by response to acetylcholine. Resuscitation restored central hemodynamics to baseline after hemorrhage. After resuscitation, inflow A1 and premucosal A3 arterioles progressively constricted (-24% and -29% change from baseline, respectively), mucosal blood flow was reduced, and ETC function was impaired. Complement inhibition prevented postresuscitation vasoconstriction and gut ischemia. This protective effect appeared to involve preservation of ETC function in the A3 vessels (SHAM 76% of maximal dilation, HEM/RES 61%, HEM/RES + sCR1 74%, P < .05). Complement inhibition preserved ETC function after HEM/RES and maintained gut perfusion. Inhibition of complement activation before resuscitation may be a useful adjunct in patients experiencing major hemorrhage and might prevent the sequelae of gut ischemia.

In Situ Formation of an Azo Bridge on Proteins Controllable by Visible Light.

PubMed

Hoppmann, Christian; Maslennikov, Innokentiy; Choe, Senyon; Wang, Lei

2015-09-09

Optical modulation of proteins provides superior spatiotemporal resolution for understanding biological processes, and photoswitches built on light-sensitive proteins have been significantly advancing neuronal and cellular studies. Small molecule photoswitches could complement protein-based switches by mitigating potential interference and affording high specificity for modulation sites. However, genetic encodability and responsiveness to nonultraviolet light, two desired properties possessed by protein photoswitches, are challenging to be engineered into small molecule photoswitches. Here we developed a small molecule photoswitch that can be genetically installed onto proteins in situ and controlled by visible light. A pentafluoro azobenzene-based photoswitchable click amino acid (F-PSCaa) was designed to isomerize in response to visible light. After genetic incorporation into proteins via the expansion of the genetic code, F-PSCaa reacts with a nearby cysteine within the protein generating an azo bridge in situ. The resultant bridge is switchable by visible light and allows conformation and binding of CaM to be regulated by such light. This photoswitch should prove valuable in optobiology for its minimal interference, site flexibility, genetic encodability, and response to the more biocompatible visible light.

SSR-enriched genetic linkage maps of bermudagrass (Cynodon dactylon × transvaalensis), and their comparison with allied plant genomes.

PubMed

Khanal, Sameer; Kim, Changsoo; Auckland, Susan A; Rainville, Lisa K; Adhikari, Jeevan; Schwartz, Brian M; Paterson, Andrew H

2017-04-01

We report SSR-enriched genetic maps of bermudagrass that: (1) reveal partial residual polysomic inheritance in the tetraploid species, and (2) provide insights into the evolution of chloridoid genomes. This study describes genetic linkage maps of two bermudagrass species, Cynodon dactylon (T89) and Cynodon transvaalensis (T574), that integrate heterologous microsatellite markers from sugarcane into frameworks built with single-dose restriction fragments (SDRFs). A maximum likelihood approach was used to construct two separate parental maps from a population of 110 F 1 progeny of a cross between the two parents. The T89 map is based on 291 loci on 34 cosegregating groups (CGs), with an average marker spacing of 12.5 cM. The T574 map is based on 125 loci on 14 CGs, with an average marker spacing of 10.7 cM. Six T89 and one T574 CG(s) deviated from disomic inheritance. Furthermore, marker segregation data and linkage phase analysis revealed partial residual polysomic inheritance in T89, suggesting that common bermudagrass is undergoing diploidization following whole genome duplication (WGD). Twenty-six T89 CGs were coalesced into 9 homo(eo)logous linkage groups (LGs), while 12 T574 CGs were assembled into 9 LGs, both putatively representing the basic chromosome complement (x = 9) of the species. Eight T89 and two T574 CGs remain unassigned. The marker composition of bermudagrass ancestral chromosomes was inferred by aligning T89 and T574 homologs, and used in comparisons to sorghum and rice genome sequences based on 108 and 91 significant blast hits, respectively. Two nested chromosome fusions (NCFs) shared by two other chloridoids (i.e., zoysiagrass and finger millet) and at least three independent translocation events were evident during chromosome number reduction from 14 in the polyploid common ancestor of Poaceae to 9 in Cynodon.

Segmental allotetraploidy and allelic interactions in buffelgrass (Pennisetum ciliare (L.) Link syn. Cenchrus ciliaris L.) as revealed by genome mapping.

PubMed

Jessup, R W; Burson, B L; Burow, O; Wang, Y W; Chang, C; Li, Z; Paterson, A H; Hussey, M A

2003-04-01

Linkage analyses increasingly complement cytological and traditional plant breeding techniques by providing valuable information regarding genome organization and transmission genetics of complex polyploid species. This study reports a genome map of buffelgrass (Pennisetum ciliare (L.) Link syn. Cenchrus ciliaris L.). Maternal and paternal maps were constructed with restriction fragment length polymorphisms (RFLPs) segregating in 87 F1 progeny from an intraspecific cross between two heterozygous genotypes. A survey of 862 heterologous cDNAs and gDNAs from across the Poaceae, as well as 443 buffelgrass cDNAs, yielded 100 and 360 polymorphic probes, respectively. The maternal map included 322 RFLPs, 47 linkage groups, and 3464 cM, whereas the paternal map contained 245 RFLPs, 42 linkage groups, and 2757 cM. Approximately 70 to 80% of the buffelgrass genome was covered, and the average marker spacing was 10.8 and 11.3 cM on the respective maps. Preferential pairing was indicated between many linkage groups, which supports cytological reports that buffelgrass is a segmental allotetraploid. More preferential pairing (disomy) was found in the maternal than paternal parent across linkage groups (55 vs. 38%) and loci (48 vs. 15%). Comparison of interval lengths in 15 allelic bridges indicated significantly less meiotic recombination in paternal gametes. Allelic interactions were detected in four regions of the maternal map and were absent in the paternal map.

Isolation and Characterization of Sex-Linked Female-Sterile Mutants in DROSOPHILA MELANOGASTER with Special Attention to Eggshell Mutants

PubMed Central

Komitopoulou, Katia; Gans, Madeleine; Margaritis, Lukas H.; Kafatos, Fotis C.; Masson, Michele

1983-01-01

To study genes that function mainly or exclusively during oogenesis, we have isolated and analyzed female-sterile mutations, with special emphasis on those that affect eggshell formation. Following treatment that induced 61 to 66% lethals, 8.1% of the 1071 X chromosomes tested carried recessive female sterility mutations (87 isolates), and 8.0% carried partial female-sterile mutations (86 isolates), respectively. In addition, three dominant female steriles were recovered. Some of the mutants had very low fecundity, and others laid morphologically normal eggs that failed to develop. A third category included 29 mutants that laid eggs with morphological abnormalities: 26 were female steriles, two were partial female steriles and one was fertile. Mutants of this third category were characterized in some detail and compared with 40 previously isolated mutants that laid similarly abnormal eggs. Approximately 28–31 complementation groups with morphological abnormalities were detected, some of which were large allelic series (11, 9, 7, 6 and 5 alleles). Twenty-four groups were mapped genetically or cytogenetically, and 21 were partially characterized by ultrastructural and biochemical procedures. Of the latter, one group showed clear deficiency of yolk proteins, and nine showed prominent ultrastructural defects in the chorion (at least eight accompanied by deficiencies in characterized chorion proteins). At least six groups with clear-cut effects were found at loci not previously identified with known chorion structural genes. PMID:17246182

Age-Related Macular Degeneration: Genetics and Biology Coming Together

PubMed Central

Fritsche, Lars G.; Fariss, Robert N.; Stambolian, Dwight; Abecasis, Gonçalo R.; Curcio, Christine A.

2014-01-01

Genetic and genomic studies have enhanced our understanding of complex neurodegenerative diseases that exert a devastating impact on individuals and society. One such disease, age-related macular degeneration (AMD), is a major cause of progressive and debilitating visual impairment. Since the pioneering discovery in 2005 of complement factor H (CFH) as a major AMD susceptibility gene, extensive investigations have confirmed 19 additional genetic risk loci, and more are anticipated. In addition to common variants identified by now-conventional genome-wide association studies, targeted genomic sequencing and exome-chip analyses are uncovering rare variant alleles of high impact. Here, we provide a critical review of the ongoing genetic studies and of common and rare risk variants at a total of 20 susceptibility loci, which together explain 40–60% of the disease heritability but provide limited power for diagnostic testing of disease risk. Identification of these susceptibility loci has begun to untangle the complex biological pathways underlying AMD pathophysiology, pointing to new testable paradigms for treatment. PMID:24773320

Genome-association analysis of Korean Holstein milk traits using genomic estimated breeding value.

PubMed

Shin, Donghyun; Lee, Chul; Park, Kyoung-Do; Kim, Heebal; Cho, Kwang-Hyeon

2017-03-01

Holsteins are known as the world's highest-milk producing dairy cattle. The purpose of this study was to identify genetic regions strongly associated with milk traits (milk production, fat, and protein) using Korean Holstein data. This study was performed using single nucleotide polymorphism (SNP) chip data (Illumina BovineSNP50 Beadchip) of 911 Korean Holstein individuals. We inferred each genomic estimated breeding values based on best linear unbiased prediction (BLUP) and ridge regression using BLUPF90 and R. We then performed a genome-wide association study and identified genetic regions related to milk traits. We identified 9, 6, and 17 significant genetic regions related to milk production, fat and protein, respectively. These genes are newly reported in the genetic association with milk traits of Holstein. This study complements a recent Holstein genome-wide association studies that identified other SNPs and genes as the most significant variants. These results will help to expand the knowledge of the polygenic nature of milk production in Holsteins.

Genome-association analysis of Korean Holstein milk traits using genomic estimated breeding value

PubMed Central

Shin, Donghyun; Lee, Chul; Park, Kyoung-Do; Kim, Heebal; Cho, Kwang-hyeon

2017-01-01

Objective Holsteins are known as the world’s highest-milk producing dairy cattle. The purpose of this study was to identify genetic regions strongly associated with milk traits (milk production, fat, and protein) using Korean Holstein data. Methods This study was performed using single nucleotide polymorphism (SNP) chip data (Illumina BovineSNP50 Beadchip) of 911 Korean Holstein individuals. We inferred each genomic estimated breeding values based on best linear unbiased prediction (BLUP) and ridge regression using BLUPF90 and R. We then performed a genome-wide association study and identified genetic regions related to milk traits. Results We identified 9, 6, and 17 significant genetic regions related to milk production, fat and protein, respectively. These genes are newly reported in the genetic association with milk traits of Holstein. Conclusion This study complements a recent Holstein genome-wide association studies that identified other SNPs and genes as the most significant variants. These results will help to expand the knowledge of the polygenic nature of milk production in Holsteins. PMID:26954162

Characterization of phagocytic hemocytes in Ornithodoros moubata (Acari: Ixodidae).

PubMed

Inoue, N; Hanada, K; Tsuji, N; Igarashi, I; Nagasawa, H; Mikami, T; Fujisaki, K

2001-07-01

Effects of fetal bovine serum (FBS) and complement on phagocytic activity in Ornithodaros moubata (Murray 1877) hemocytes and protease activity in the hemocytes were examined. At least three morphologically different cell types, granulocytes, plasmatocytes, and prohemocytes, were detected in hemolymph of O. moubata, and granulocytes and plasmatocytes showed phagocytic activity. FBS altered phagocytic activity of granulocytes, and complement affected phagocytic activity of plasmatocytes. Ticks were inoculated with fluorescent polystyrene beads in combination with FBS or complement. The average number of beads in granulocytes was significantly higher in the FBS injected group than the control (P < 0.01). The percentage of bead-ingesting plasmatocytes in complement inoculated ticks was significantly lower than that in heat-inactivated complement inoculated and control ticks (P < 0.05). Proteases of tick hemocytes localized in small granules in the cytoplasm not only in phagocytic hemocytes but also in prohemocytes. Results suggested modulation of tick hemocyte function through serum components, and digestion of phagocytosed foreign bodies in the hemocytes.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chan, Chi Ho; Levar, Caleb E.; Zacharoff, Lori

Metal reduction by members of the Geobacteraceae is encoded by multiple gene clusters, and the study of extracellular electron transfer often requires biofilm development on surfaces. Genetic tools that utilize polar antibiotic cassette insertions limit mutant construction and complementation. In addition, unstable plasmids create metabolic burdens that slow growth, and the presence of antibiotics such as kanamycin can interfere with the rate and extent of Geobacter biofilm growth. We report here genetic system improvements for the model anaerobic metal-reducing bacterium Geobacter sulfurreducens. A motile strain of G. sulfurreducens was constructed by precise removal of a transposon interrupting the fgrM flagellarmore » regulator gene using SacB/sucrose counterselection, and Fe(III) citrate reduction was eliminated by deletion of the gene encoding the inner membrane cytochrome imcH. We also show that RK2-based plasmids were maintained in G. sulfurreducens for over 15 generations in the absence of antibiotic selection in contrast to unstable pBBR1 plasmids. Therefore, we engineered a series of new RK2 vectors containing native constitutive Geobacter promoters, and modified one of these promoters for VanR-dependent induction by the small aromatic carboxylic acid vanillate. Inducible plasmids fully complemented Δ imcH mutants for Fe(III) reduction, Mn(IV) oxide reduction, and growth on poised electrodes. A real-time, high-throughput Fe(III) citrate reduction assay is described that can screen numerous G. sulfurreducens strain constructs simultaneously and shows the sensitivity of imcH expression by the vanillate system. Lastly, these tools will enable more sophisticated genetic studies in G. sulfurreducens without polar insertion effects or need for multiple antibiotics.« less

Complementation of Conjugation Functions of Streptomyces lividans Plasmid pIJ101 by the Related Streptomyces Plasmid pSB24.2

PubMed Central

Pettis, Gregg S.; Prakash, Shubha

1999-01-01

A database search revealed extensive sequence similarity between Streptomyces lividans plasmid pIJ101 and Streptomyces plasmid pSB24.2, which is a deletion derivative of Streptomyces cyanogenus plasmid pSB24.1. The high degree of relatedness between the two plasmids allowed the construction of a genetic map of pSB24.2, consisting of putative transfer and replication loci. Two pSB24.2 loci, namely, the cis-acting locus for transfer (clt) and the transfer-associated korB gene, were shown to be capable of complementing the pIJ101 clt and korB functions, respectively, a result that is consistent with the notion that pIJ101 and the parental plasmid pSB24.1 encode highly similar, if not identical, conjugation systems. PMID:10419972

Genome-Wide Association Studies Identify Heavy Metal ATPase3 as the Primary Determinant of Natural Variation in Leaf Cadmium in Arabidopsis thaliana

PubMed Central

Chao, Dai-Yin; Silva, Adriano; Baxter, Ivan; Huang, Yu S.; Nordborg, Magnus; Danku, John; Lahner, Brett; Yakubova, Elena; Salt, David E.

2012-01-01

Understanding the mechanism of cadmium (Cd) accumulation in plants is important to help reduce its potential toxicity to both plants and humans through dietary and environmental exposure. Here, we report on a study to uncover the genetic basis underlying natural variation in Cd accumulation in a world-wide collection of 349 wild collected Arabidopsis thaliana accessions. We identified a 4-fold variation (0.5–2 µg Cd g−1 dry weight) in leaf Cd accumulation when these accessions were grown in a controlled common garden. By combining genome-wide association mapping, linkage mapping in an experimental F2 population, and transgenic complementation, we reveal that HMA3 is the sole major locus responsible for the variation in leaf Cd accumulation we observe in this diverse population of A. thaliana accessions. Analysis of the predicted amino acid sequence of HMA3 from 149 A. thaliana accessions reveals the existence of 10 major natural protein haplotypes. Association of these haplotypes with leaf Cd accumulation and genetics complementation experiments indicate that 5 of these haplotypes are active and 5 are inactive, and that elevated leaf Cd accumulation is associated with the reduced function of HMA3 caused by a nonsense mutation and polymorphisms that change two specific amino acids. PMID:22969436

Genetic and cytogenetic analysis of the olive fruit fly Bactrocera oleae (Diptera: Tephritidae).

PubMed

Mavragani-Tsipidou, P

2002-09-01

The genetic and cytogenetic characteristics of one of the major agricultural pests, the olive fruit fly Bactmcera oleae, are presented here. The mitotic metaphase complement of this insect consists of six pairs of chromosomes including one pair of heteromorphic sex chromosomes, with the male being the heterogametic sex. The analysis of the polytene complements of three larval tissues, the fat body, the salivary glands and the Malpighian tubules of this pest has shown (a) a total number of five long chromosomes (10 polytene arms) that correspond to the five autosomes of the mitotic nuclei and a heterochromatic mass corresponding to the sex chromosomes, (b) the constancy of the banding pattern of the three somatic tissues, (c) the absence of a typical chromocenter as an accumulation of heterochromatin, (d) the existence of reverse tandem duplications, and (e) the presence of toroid tips of the chromosome arms. The in situ hybridization of genes or DNA sequences to the salivary gland polytene chromosomes of B. oleae provided molecular markers for all five autosomes and permitted the establishment of chromosomal homologies among B. olea, B. tryoni and Ceratitis capitata. The heat shock response of B. oleae, as revealed by heat-inducible puffing and protein pattern, shows a higher thermotolerance than Drosophila melanogaster.

Diversity in Genetic In Vivo Methods for Protein-Protein Interaction Studies: from the Yeast Two-Hybrid System to the Mammalian Split-Luciferase System

PubMed Central

Stynen, Bram; Tournu, Hélène; Tavernier, Jan

2012-01-01

Summary: The yeast two-hybrid system pioneered the field of in vivo protein-protein interaction methods and undisputedly gave rise to a palette of ingenious techniques that are constantly pushing further the limits of the original method. Sensitivity and selectivity have improved because of various technical tricks and experimental designs. Here we present an exhaustive overview of the genetic approaches available to study in vivo binary protein interactions, based on two-hybrid and protein fragment complementation assays. These methods have been engineered and employed successfully in microorganisms such as Saccharomyces cerevisiae and Escherichia coli, but also in higher eukaryotes. From single binary pairwise interactions to whole-genome interactome mapping, the self-reassembly concept has been employed widely. Innovative studies report the use of proteins such as ubiquitin, dihydrofolate reductase, and adenylate cyclase as reconstituted reporters. Protein fragment complementation assays have extended the possibilities in protein-protein interaction studies, with technologies that enable spatial and temporal analyses of protein complexes. In addition, one-hybrid and three-hybrid systems have broadened the types of interactions that can be studied and the findings that can be obtained. Applications of these technologies are discussed, together with the advantages and limitations of the available assays. PMID:22688816

DOE Office of Scientific and Technical Information (OSTI.GOV)

Greene, T.W.; Chantler, S.E.; Kahn, M.L.

ADPglucose pyrophosphorylase (glucose-1-phosphate adenylytransferase; AD P:{alpha}-D-glucose-1-phosphate adenylyltransferase, EC 2.7.7.27) catalyzes a key regulatory step in {alpha}-glucan synthesis in bacteria and higher plants. We have previously shown that the expression of the cDNA sequences of the potato tuber large (LS) and small (SS) subunits yielded a functional heterotetrameric enzyme capable of complementing a mutation in the single AGP (glgC) structural gene of Escherichia coli. This heterologous complementation provides a powerful genetic approach to obtain biochemical information on the specific roles of LS and SS in enzyme function. By mutagenizing the LS cDNA with hydroxylamine and then coexpressing with wild-type SS inmore » an E. coli glgC{sup {minus}} strain, >350 mutant colonies were identified that were impaired in glycogen production. One mutant exhibited enzymatic and antigen levels comparable to the wild-type recombinant enzyme but required 45-fold greater levels of the activator 3-phosphoglycerate for maximum activity. Sequence analysis identified a single nucleotide change that resulted in the change of Pro-52 to Leu. This heterologous genetic system provides and efficient means to identify residues important for catalysis and allosteric functioning and should lead to novel approaches to increase plant productivity. 31 refs., 4 figs., 1 tab.« less

Loss of diacylglycerol kinase epsilon in mice causes endothelial distress and impairs glomerular Cox-2 and PGE2 production

PubMed Central

Zhu, Jili; Chaki, Moumita; Lu, Dongmei; Ren, Chongyu; Wang, Shan-Shan; Rauhauser, Alysha; Li, Binghua; Zimmerman, Susan; Jun, Bokkyoo; Du, Yong; Vadnagara, Komal; Wang, Hanquin; Elhadi, Sarah; Quigg, Richard J.; Topham, Matthew K.; Mohan, Chandra; Ozaltin, Fatih; Zhou, Xin J.; Marciano, Denise K.; Bazan, Nicolas G.

2016-01-01

Thrombotic microangiopathy (TMA) is a disorder characterized by microvascular occlusion that can lead to thrombocytopenia, hemolytic anemia, and glomerular damage. Complement activation is the central event in most cases of TMA. Primary forms of TMA are caused by mutations in genes encoding components of the complement or regulators of the complement cascade. Recently, we and others have described a genetic form of TMA caused by mutations in the gene diacylglycerol kinase-ε (DGKE) that encodes the lipid kinase DGKε (Lemaire M, Fremeaux-Bacchi V, Schaefer F, Choi MR, Tang WH, Le Quintrec M, Fakhouri F, Taque S, Nobili F, Martinez F, Ji WZ, Overton JD, Mane SM, Nurnberg G, Altmuller J, Thiele H, Morin D, Deschenes G, Baudouin V, Llanas B, Collard L, Majid MA, Simkova E, Nurnberg P, Rioux-Leclerc N, Moeckel GW, Gubler MC, Hwa J, Loirat C, Lifton RP. Nat Genet 45: 531–536, 2013; Ozaltin F, Li BH, Rauhauser A, An SW, Soylemezoglu O, Gonul II, Taskiran EZ, Ibsirlioglu T, Korkmaz E, Bilginer Y, Duzova A, Ozen S, Topaloglu R, Besbas N, Ashraf S, Du Y, Liang CY, Chen P, Lu DM, Vadnagara K, Arbuckle S, Lewis D, Wakeland B, Quigg RJ, Ransom RF, Wakeland EK, Topham MK, Bazan NG, Mohan C, Hildebrandt F, Bakkaloglu A, Huang CL, Attanasio M. J Am Soc Nephrol 24: 377–384, 2013). DGKε is unrelated to the complement pathway, which suggests that unidentified pathogenic mechanisms independent of complement dysregulation may result in TMA. Studying Dgke knockout mice may help to understand the pathogenesis of this disease, but no glomerular phenotype has been described in these animals so far. Here we report that Dgke null mice present subclinical microscopic anomalies of the glomerular endothelium and basal membrane that worsen with age and develop glomerular capillary occlusion when exposed to nephrotoxic serum. We found that induction of cyclooxygenase-2 and of the proangiogenic prostaglandin E2 are impaired in Dgke null kidneys and are associated with reduced expression of the antithrombotic cell adhesion molecule platelet endothelial cell adhesion molecule-1/CD31 in the glomerular endothelium. Notably, prostaglandin E2 supplementation was able to rescue motility defects of Dgke knockdown cells in vitro and to restore angiogenesis in a test in vivo. Our results unveil an unexpected role of Dgke in the induction of cyclooxygenase-2 and in the regulation of glomerular prostanoids synthesis under stress. PMID:26887830

Loss of diacylglycerol kinase epsilon in mice causes endothelial distress and impairs glomerular Cox-2 and PGE2 production.

PubMed

Zhu, Jili; Chaki, Moumita; Lu, Dongmei; Ren, Chongyu; Wang, Shan-Shan; Rauhauser, Alysha; Li, Binghua; Zimmerman, Susan; Jun, Bokkyoo; Du, Yong; Vadnagara, Komal; Wang, Hanquin; Elhadi, Sarah; Quigg, Richard J; Topham, Matthew K; Mohan, Chandra; Ozaltin, Fatih; Zhou, Xin J; Marciano, Denise K; Bazan, Nicolas G; Attanasio, Massimo

2016-05-01

Thrombotic microangiopathy (TMA) is a disorder characterized by microvascular occlusion that can lead to thrombocytopenia, hemolytic anemia, and glomerular damage. Complement activation is the central event in most cases of TMA. Primary forms of TMA are caused by mutations in genes encoding components of the complement or regulators of the complement cascade. Recently, we and others have described a genetic form of TMA caused by mutations in the gene diacylglycerol kinase-ε (DGKE) that encodes the lipid kinase DGKε (Lemaire M, Fremeaux-Bacchi V, Schaefer F, Choi MR, Tang WH, Le Quintrec M, Fakhouri F, Taque S, Nobili F, Martinez F, Ji WZ, Overton JD, Mane SM, Nurnberg G, Altmuller J, Thiele H, Morin D, Deschenes G, Baudouin V, Llanas B, Collard L, Majid MA, Simkova E, Nurnberg P, Rioux-Leclerc N, Moeckel GW, Gubler MC, Hwa J, Loirat C, Lifton RP. Nat Genet 45: 531-536, 2013; Ozaltin F, Li BH, Rauhauser A, An SW, Soylemezoglu O, Gonul II, Taskiran EZ, Ibsirlioglu T, Korkmaz E, Bilginer Y, Duzova A, Ozen S, Topaloglu R, Besbas N, Ashraf S, Du Y, Liang CY, Chen P, Lu DM, Vadnagara K, Arbuckle S, Lewis D, Wakeland B, Quigg RJ, Ransom RF, Wakeland EK, Topham MK, Bazan NG, Mohan C, Hildebrandt F, Bakkaloglu A, Huang CL, Attanasio M. J Am Soc Nephrol 24: 377-384, 2013). DGKε is unrelated to the complement pathway, which suggests that unidentified pathogenic mechanisms independent of complement dysregulation may result in TMA. Studying Dgke knockout mice may help to understand the pathogenesis of this disease, but no glomerular phenotype has been described in these animals so far. Here we report that Dgke null mice present subclinical microscopic anomalies of the glomerular endothelium and basal membrane that worsen with age and develop glomerular capillary occlusion when exposed to nephrotoxic serum. We found that induction of cyclooxygenase-2 and of the proangiogenic prostaglandin E2 are impaired in Dgke null kidneys and are associated with reduced expression of the antithrombotic cell adhesion molecule platelet endothelial cell adhesion molecule-1/CD31 in the glomerular endothelium. Notably, prostaglandin E2 supplementation was able to rescue motility defects of Dgke knockdown cells in vitro and to restore angiogenesis in a test in vivo. Our results unveil an unexpected role of Dgke in the induction of cyclooxygenase-2 and in the regulation of glomerular prostanoids synthesis under stress. Copyright © 2016 the American Physiological Society.

Age-related macular degeneration: genome-wide association studies to translation.

PubMed

Black, James R M; Clark, Simon J

2016-04-01

In recent years, genome-wide association studies (GWAS), which are able to analyze the contribution to disease of genetic variations that are common within a population, have attracted considerable investment. Despite identifying genetic variants for many conditions, they have been criticized for yielding data with minimal clinical utility. However, in this regard, age-related macular degeneration (AMD), the most common form of blindness in the Western world, is a striking exception. Through GWAS, common genetic variants at a number of loci have been discovered. Two loci in particular, including genes of the complement cascade on chromosome 1 and the ARMS2/HTRA1 genes on chromosome 10, have been shown to convey significantly increased susceptibility to developing AMD. Today, although it is possible to screen individuals for a genetic predisposition to the disease, effective interventional strategies for those at risk of developing AMD are scarce. Ongoing research in this area is nonetheless promising. After providing brief overviews of AMD and common disease genetics, we outline the main recent advances in the understanding of AMD, particularly those made through GWAS. Finally, the true merit of these findings and their current and potential translational value is examined.Genet Med 18 4, 283-289.

Ultraviolet light-resistant primary transfectants of xeroderma pigmentosum cells are also DNA repair-proficient

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stark, M.; Naiman, T.; Canaani, D.

1989-08-15

In a previous work, an immortal xeroderma pigmentosum cell line belonging to complementation group C was complemented to a UV-resistant phenotype by transfection with a human cDNA clone library. We now report that the primary transformants selected for UV-resistance also acquired normal levels of DNA repair. This was assessed both by measurement of UV-induced ({sup 3}H)thymidine incorporation and by equilibrium sedimentation analysis of repair-DNA synthesis. Therefore, the transduced DNA element which confers normal UV-resistance also corrects the excision repair defect of the xeroderma pigmentosum group C cell line.

Molybdenum cofactor (chlorate-resistant) mutants of Klebsiella pneumoniae M5al can use hypoxanthine as the sole nitrogen source.

PubMed Central

Garzón, A; Li, J; Flores, A; Casadesus, J; Stewart, V

1992-01-01

Selection for chlorate resistance yields mol (formerly chl) mutants with defects in molybdenum cofactor synthesis. Complementation and genetic mapping analyses indicated that the Klebsiella pneumoniae mol genes are functionally homologous to those of Escherichia coli and occupy analogous genetic map positions. Hypoxanthine utilization in other organisms requires molybdenum cofactor as a component of xanthine dehydrogenase, and thus most chlorate-resistant mutants cannot use hypoxanthine as a sole source of nitrogen. Surprisingly, the K. pneumoniae mol mutants and the mol+ parent grew equally well with hypoxanthine as the sole nitrogen source, suggesting that K. pneumoniae has a molybdenum cofactor-independent pathway for hypoxanthine utilization. PMID:1400180

Functional Evolution of a cis-Regulatory Module

PubMed Central

Palsson, Arnar; Alekseeva, Elena; Bergman, Casey M; Nathan, Janaki; Kreitman, Martin

2005-01-01

Lack of knowledge about how regulatory regions evolve in relation to their structure–function may limit the utility of comparative sequence analysis in deciphering cis-regulatory sequences. To address this we applied reverse genetics to carry out a functional genetic complementation analysis of a eukaryotic cis-regulatory module—the even-skipped stripe 2 enhancer—from four Drosophila species. The evolution of this enhancer is non-clock-like, with important functional differences between closely related species and functional convergence between distantly related species. Functional divergence is attributable to differences in activation levels rather than spatiotemporal control of gene expression. Our findings have implications for understanding enhancer structure–function, mechanisms of speciation and computational identification of regulatory modules. PMID:15757364

Quantitative assessment of cellular uptake and cytosolic access of antibody in living cells by an enhanced split GFP complementation assay

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Ji-sun; Choi, Dong-Ki; Park, Seong-wook

Considering the number of cytosolic proteins associated with many diseases, development of cytosol-penetrating molecules from outside of living cells is highly in demand. To gain access to the cytosol after cellular uptake, cell-penetrating molecules should be released from intermediate endosomes prior to the lysosomal degradation. However, it is very challenging to distinguish the pool of cytosolic-released molecules from those trapped in the endocytic vesicles. Here we describe a method to directly demonstrate the cytosolic localization and quantification of cytosolic amount of a cytosol-penetrating IgG antibody, TMab4, based on enhanced split GFP complementation system. We generated TMab4 genetically fused with onemore » GFP fragment and separately established HeLa cells expressing the other GFP fragment in the cytosol such that the complemented GFP fluorescence is observed only when extracellular-treated TMab4 reaches the cytosol after cellular internalization. The high affinity interactions between streptavidin-binding peptide 2 and streptavidin was employed as respective fusion partners of GFP fragments to enhance the sensitivity of GFP complementation. With this method, cytosolic concentration of TMab4 was estimated to be about 170 nM after extracellular treatment of HeLa cells with 1 μM TMab4 for 6 h. We also found that after cellular internalization into living cells, nearly 1.3–4.3% of the internalized TMab4 molecules escaped into the cytosol from the endocytic vesicles. Our enhanced split GFP complementation assay provides a useful tool to directly quantify cytosolic amount of cytosol-penetrating agents and allows cell-based high-throughput screening for cytosol-penetrating agents with increased endosomal-escaping activity.« less

Use of eculizumab and plasma exchange in successful combined liver-kidney transplantation in a case of atypical HUS associated with complement factor H mutation.

PubMed

Tran, Ha; Chaudhuri, Abanti; Concepcion, Waldo; Grimm, Paul C

2014-03-01

Atypical hemolytic uremic syndrome (aHUS) evolves into end-stage renal failure in nearly half of affected patients and is associated with defective regulation of the alternative complement pathway. Patients with a complement factor H (CFH) mutation have a 30-100% risk of graft loss due to aHUS recurrence or graft thrombosis. Since CFH is produced predominantly by the liver, combined liver-kidney transplant is a curative treatment option. One major unexpected risk includes liver failure secondary to uncontrolled complement activation. We report a successful combined liver-kidney transplantation with perioperative plasma exchange and use of the humanized anti-C5 monoclonal antibody eculizumab. An 11-month-old female presented with oliguric renal failure after 3 weeks of flu-like symptoms in the absence of diarrhea. Following the identification of Escherichia coli 0157:H7 in her stool, she was discharged home on peritoneal dialysis with a diagnosis of Shiga toxin-associated HUS. Three months later, she developed severe anemia, thrombocytopenia, and neurological involvement. aHUS was diagnosed and confirmed, and genetic testing revealed a mutation in CFH SCR20. Once donor organs became available, she received preoperative plasma exchange followed by eculizumab infusion with intra-operative fresh frozen plasma prior to combined liver-kidney transplant. At 19 months post-transplant, she continues to have excellent allograft and liver function without signs of disease recurrence. Perioperative use of eculizumab in conjunction with plasma exchange during simultaneous liver-kidney transplant can be used to inhibit terminal complement activity, thereby optimizing successful transplantation by reducing the risk of graft thrombosis.

Quantitative assessment of cellular uptake and cytosolic access of antibody in living cells by an enhanced split GFP complementation assay.

PubMed

Kim, Ji-sun; Choi, Dong-Ki; Park, Seong-wook; Shin, Seung-Min; Bae, Jeomil; Kim, Dong-Myung; Yoo, Tae Hyeon; Kim, Yong-Sung

2015-11-27

Considering the number of cytosolic proteins associated with many diseases, development of cytosol-penetrating molecules from outside of living cells is highly in demand. To gain access to the cytosol after cellular uptake, cell-penetrating molecules should be released from intermediate endosomes prior to the lysosomal degradation. However, it is very challenging to distinguish the pool of cytosolic-released molecules from those trapped in the endocytic vesicles. Here we describe a method to directly demonstrate the cytosolic localization and quantification of cytosolic amount of a cytosol-penetrating IgG antibody, TMab4, based on enhanced split GFP complementation system. We generated TMab4 genetically fused with one GFP fragment and separately established HeLa cells expressing the other GFP fragment in the cytosol such that the complemented GFP fluorescence is observed only when extracellular-treated TMab4 reaches the cytosol after cellular internalization. The high affinity interactions between streptavidin-binding peptide 2 and streptavidin was employed as respective fusion partners of GFP fragments to enhance the sensitivity of GFP complementation. With this method, cytosolic concentration of TMab4 was estimated to be about 170 nM after extracellular treatment of HeLa cells with 1 μM TMab4 for 6 h. We also found that after cellular internalization into living cells, nearly 1.3-4.3% of the internalized TMab4 molecules escaped into the cytosol from the endocytic vesicles. Our enhanced split GFP complementation assay provides a useful tool to directly quantify cytosolic amount of cytosol-penetrating agents and allows cell-based high-throughput screening for cytosol-penetrating agents with increased endosomal-escaping activity. Copyright © 2015 Elsevier Inc. All rights reserved.

Mitochondrial respiratory chain Complex I defects in Fanconi anemia complementation group A.

PubMed

Ravera, Silvia; Vaccaro, Daniele; Cuccarolo, Paola; Columbaro, Marta; Capanni, Cristina; Bartolucci, Martina; Panfoli, Isabella; Morelli, Alessandro; Dufour, Carlo; Cappelli, Enrico; Degan, Paolo

2013-10-01

Fanconi anemia (FA) is a rare and complex inherited blood disorder of the child. At least 15 genes are associated with the disease. The highest frequency of mutations belongs to groups A, C and G. Genetic instability and cytokine hypersensitivity support the selection of leukemic over non-leukemic stem cells. FA cellular phenotype is characterized by alterations in red-ox state, mitochondrial functionality and energy metabolism as reported in the past however a clear picture of the altered biochemical phenotype in FA is still elusive and the final biochemical defect(s) still unknown. Here we report an analysis of the respiratory fluxes in FANCA primary fibroblasts, lymphocytes and lymphoblasts. FANCA mutants show defective respiration through Complex I, diminished ATP production and metabolic sufferance with an increased AMP/ATP ratio. Respiration in FANCC mutants is normal. Treatment with N-acetyl-cysteine (NAC) restores oxygen consumption to normal level. Defective respiration in FANCA mutants appear correlated with the FA pro-oxidative phenotype which is consistent with the altered morphology of FANCA mitochondria. Electron microscopy measures indeed show profound alterations in mitochondrial ultrastructure and shape. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Update of the human and mouse Fanconi anemia genes.

PubMed

Dong, Hongbin; Nebert, Daniel W; Bruford, Elspeth A; Thompson, David C; Joenje, Hans; Vasiliou, Vasilis

2015-11-24

Fanconi anemia (FA) is a recessively inherited disease manifesting developmental abnormalities, bone marrow failure, and increased risk of malignancies. Whereas FA has been studied for nearly 90 years, only in the last 20 years have increasing numbers of genes been implicated in the pathogenesis associated with this genetic disease. To date, 19 genes have been identified that encode Fanconi anemia complementation group proteins, all of which are named or aliased, using the root symbol "FANC." Fanconi anemia subtype (FANC) proteins function in a common DNA repair pathway called "the FA pathway," which is essential for maintaining genomic integrity. The various FANC mutant proteins contribute to distinct steps associated with FA pathogenesis. Herein, we provide a review update of the 19 human FANC and their mouse orthologs, an evolutionary perspective on the FANC genes, and the functional significance of the FA DNA repair pathway in association with clinical disorders. This is an example of a set of genes--known to exist in vertebrates, invertebrates, plants, and yeast--that are grouped together on the basis of shared biochemical and physiological functions, rather than evolutionary phylogeny, and have been named on this basis by the HUGO Gene Nomenclature Committee (HGNC).

Mutations in new cell cycle genes that fail to complement a multiply mutant third chromosome of Drosophila.

PubMed

White-Cooper, H; Carmena, M; Gonzalez, C; Glover, D M

1996-11-01

We have simultaneously screened for new alleles and second site mutations that fail to complement five cell cycle mutations of Drosphila carried on a single third chromosome (gnu, polo, mgr, asp, stg). Females that are either transheterozygous for scott of the antartic (scant) and polo, or homozygous for scant produce embryos that show mitotic defects. A maternal effect upon embryonic mitoses is also seen in embryos derived from females transheterozygous with helter skelter (hsk) and either mgr or asp. cleopatra (cleo), fails to complement asp but is not uncovered by a deficiency for asp. The mitotic phenotype of larvae heterozygous for cleo and the multiple mutant chromosome is similar to weak alleles of asp, but there are no defects in male meiosis. Mutations that failed to complement stg fell into two complementation groups corresponding to stg and a new gene noose. Three of the new stg alleles are early zygotic lethals, whereas the fourth is a pharate adult lethal allele that affects both mitosis and meiosis. Mutations in noose fully complement a small deficiency that removes stg, but when placed in trans to certain stg alleles, result in late lethality and mitotic abnormalities in larval brains.

Genetic studies on a nitrogen-fixing cyanobacterium. [Anabaena; Escherichi coli

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wolk, C.P.; Cardemil, L.; Elhai, J.

1987-04-01

Mutants of Anabaena PCC7120 capable of aerobic growth with NO/sub 3//sup -/ but not N/sub 2/, and capable of microaerobic reduction of C/sub 2/H/sub 2/, were isolated by penicillin enrichment after UV irradiation. Heterocysts of two mutants lack the principal envelope glycolipid, those of EF116 have a non-cohesive envelope polysaccharide, and those of other strains have other defects. A Nm/sup r/ cosmid library of DNA from wild type Anabaena PCC7120 was established in Escherichia coli bearing the Ap helper plasmid pDS4101. A conjugative plasmid was introduced, and the bacteria replicated to lawns of individual mutant strains of Anabaena. After onemore » day of non-selective growth, selection was applied for Nm/sup r/ and nitrogen fixation. Overlapping cosmids complementing EF116 and one complementing another mutant have been mapped. The complementing genes are thought to act early in differentiation. Inclusion, in an E. coli donor of an appropriate methylase gene enhanced, by a factor of 10/sup 2/ to 10/sup 3/, transfer to Anabaena PCC7120 of a plasmid containing numerous sites for the Anabaena restriction endonuclease, AvaII.« less

Mathematical and computational approaches can complement experimental studies of host-pathogen interactions.

PubMed

Kirschner, Denise E; Linderman, Jennifer J

2009-04-01

In addition to traditional and novel experimental approaches to study host-pathogen interactions, mathematical and computer modelling have recently been applied to address open questions in this area. These modelling tools not only offer an additional avenue for exploring disease dynamics at multiple biological scales, but also complement and extend knowledge gained via experimental tools. In this review, we outline four examples where modelling has complemented current experimental techniques in a way that can or has already pushed our knowledge of host-pathogen dynamics forward. Two of the modelling approaches presented go hand in hand with articles in this issue exploring fluorescence resonance energy transfer and two-photon intravital microscopy. Two others explore virtual or 'in silico' deletion and depletion as well as a new method to understand and guide studies in genetic epidemiology. In each of these examples, the complementary nature of modelling and experiment is discussed. We further note that multi-scale modelling may allow us to integrate information across length (molecular, cellular, tissue, organism, population) and time (e.g. seconds to lifetimes). In sum, when combined, these compatible approaches offer new opportunities for understanding host-pathogen interactions.

Coagulation and complement system in critically ill patients.

PubMed

Helling, H; Stephan, B; Pindur, G

2015-01-01

Activation of coagulation and inflammatory response including the complement system play a major role in the pathogenesis of critical illness. However, only limited data are available addressing the relationship of both pathways and its assessment of a predictive value for the clinical outcome in intense care medicine. Therefore, parameters of the coagulation and complement system were studied in patients with septicaemia and multiple trauma regarded as being exemplary for critical illness. 34 patients (mean age: 51.38 years (±16.57), 15 females, 19 males) were investigated at day 1 of admittance to the intensive care unit (ICU). Leukocytes, complement factors C3a and C5a were significantly (p <  0.0500) higher in sepsis than in trauma, whereas platelet count and plasma fibrinogen were significantly lower in multiple trauma. Activation markers of coagulation were elevated in both groups, however, thrombin-antithrombin-complex was significantly higher in multiple trauma. DIC scores of 5 were not exceeded in any of the two groups. Analysing the influences on mortality (11/34; 32.35% ), which was not different in both groups, non-survivors were significantly older, had significantly higher multiple organ failure (MOF) scores, lactate, abnormal prothrombin times and lower C1-inhibitor activities, even more pronounced in early deaths, than survivors. In septic non-survivors protein C was significantly lower than in trauma. We conclude from these data that activation of the complement system as part of the inflammatory response is a significant mechanism in septicaemia, whereas loss and consumption of blood components including parts of the coagulation and complement system is more characteristic for multiple trauma. Protein C in case of severe reduction might be of special concern for surviving in sepsis. Activation of haemostasis was occurring in both diseases, however, overt DIC was not confirmed in this study to be a leading mechanism in critically ill patients. MOF score, lactate, C1-inhibitor and prothrombin time have been the only statistically significant predictors for lethal outcome suggesting that organ function, microcirculation, haemostasis and inflammatory response are essential elements of the pathomechanism and clinical course of diseases among critically ill patients.

Caenorhabditis elegans: An Emerging Model in Biomedical and Environmental Toxicology

PubMed Central

Leung, Maxwell C. K.; Williams, Phillip L.; Benedetto, Alexandre; Au, Catherine; Helmcke, Kirsten J.; Aschner, Michael; Meyer, Joel N.

2008-01-01

The nematode Caenorhabditis elegans has emerged as an important animal model in various fields including neurobiology, developmental biology, and genetics. Characteristics of this animal model that have contributed to its success include its genetic manipulability, invariant and fully described developmental program, well-characterized genome, ease of maintenance, short and prolific life cycle, and small body size. These same features have led to an increasing use of C. elegans in toxicology, both for mechanistic studies and high-throughput screening approaches. We describe some of the research that has been carried out in the areas of neurotoxicology, genetic toxicology, and environmental toxicology, as well as high-throughput experiments with C. elegans including genome-wide screening for molecular targets of toxicity and rapid toxicity assessment for new chemicals. We argue for an increased role for C. elegans in complementing other model systems in toxicological research. PMID:18566021

Mammalian synthetic biology for studying the cell.

PubMed

Mathur, Melina; Xiang, Joy S; Smolke, Christina D

2017-01-02

Synthetic biology is advancing the design of genetic devices that enable the study of cellular and molecular biology in mammalian cells. These genetic devices use diverse regulatory mechanisms to both examine cellular processes and achieve precise and dynamic control of cellular phenotype. Synthetic biology tools provide novel functionality to complement the examination of natural cell systems, including engineered molecules with specific activities and model systems that mimic complex regulatory processes. Continued development of quantitative standards and computational tools will expand capacities to probe cellular mechanisms with genetic devices to achieve a more comprehensive understanding of the cell. In this study, we review synthetic biology tools that are being applied to effectively investigate diverse cellular processes, regulatory networks, and multicellular interactions. We also discuss current challenges and future developments in the field that may transform the types of investigation possible in cell biology. © 2017 Mathur et al.

Engineering and Functional Analysis of Mitotic Kinases Through Chemical Genetics.

PubMed

Jones, Mathew J K; Jallepalli, Prasad V

2016-01-01

During mitosis, multiple protein kinases transform the cytoskeleton and chromosomes into new and highly dynamic structures that mediate the faithful transmission of genetic information and cell division. However, the large number and strong conservation of mammalian kinases in general pose significant obstacles to interrogating them with small molecules, due to the difficulty in identifying and validating those which are truly selective. To overcome this problem, a steric complementation strategy has been developed, in which a bulky "gatekeeper" residue within the active site of the kinase of interest is replaced with a smaller amino acid, such as glycine or alanine. The enlarged catalytic pocket can then be targeted in an allele-specific manner with bulky purine analogs. This strategy provides a general framework for dissecting kinase function with high selectivity, rapid kinetics, and reversibility. In this chapter we discuss the principles and techniques needed to implement this chemical genetic approach in mammalian cells.

In silico Evolutionary Developmental Neurobiology and the Origin of Natural Language

NASA Astrophysics Data System (ADS)

Szathmáry, Eörs; Szathmáry, Zoltán; Ittzés, Péter; Orbaán, Geroő; Zachár, István; Huszár, Ferenc; Fedor, Anna; Varga, Máté; Számadó, Szabolcs

It is justified to assume that part of our genetic endowment contributes to our language skills, yet it is impossible to tell at this moment exactly how genes affect the language faculty. We complement experimental biological studies by an in silico approach in that we simulate the evolution of neuronal networks under selection for language-related skills. At the heart of this project is the Evolutionary Neurogenetic Algorithm (ENGA) that is deliberately biomimetic. The design of the system was inspired by important biological phenomena such as brain ontogenesis, neuron morphologies, and indirect genetic encoding. Neuronal networks were selected and were allowed to reproduce as a function of their performance in the given task. The selected neuronal networks in all scenarios were able to solve the communication problem they had to face. The most striking feature of the model is that it works with highly indirect genetic encoding--just as brains do.

Optogenetic mutagenesis in Caenorhabditis elegans.

PubMed

Noma, Kentaro; Jin, Yishi

2015-12-03

Reactive oxygen species (ROS) can modify and damage DNA. Here we report an optogenetic mutagenesis approach that is free of toxic chemicals and easy to perform by taking advantage of a genetically encoded ROS generator. This method relies on the potency of ROS generation by His-mSOG, the mini singlet oxygen generator, miniSOG, fused to a histone. Caenorhabditis elegans expressing His-mSOG in the germline behave and reproduce normally, without photoinduction. Following exposure to blue light, the His-mSOG animals produce progeny with a wide range of heritable phenotypes. We show that optogenetic mutagenesis by His-mSOG induces a broad spectrum of mutations including single-nucleotide variants (SNVs), chromosomal deletions, as well as integration of extrachromosomal transgenes, which complements those derived from traditional chemical or radiation mutagenesis. The optogenetic mutagenesis expands the toolbox for forward genetic screening and also provides direct evidence that nuclear ROS can induce heritable and specific genetic mutations.

Optogenetic mutagenesis in Caenorhabditis elegans

PubMed Central

Noma, Kentaro; Jin, Yishi

2015-01-01

Reactive oxygen species (ROS) can modify and damage DNA. Here we report an optogenetic mutagenesis approach that is free of toxic chemicals and easy to perform by taking advantage of a genetically encoded ROS generator. This method relies on the potency of ROS generation by His-mSOG, the mini singlet oxygen generator, miniSOG, fused to a histone. Caenorhabditis elegans expressing His-mSOG in the germline behave and reproduce normally, without photoinduction. Following exposure to blue light, the His-mSOG animals produce progeny with a wide range of heritable phenotypes. We show that optogenetic mutagenesis by His-mSOG induces a broad spectrum of mutations including single-nucleotide variants (SNVs), chromosomal deletions, as well as integration of extrachromosomal transgenes, which complements those derived from traditional chemical or radiation mutagenesis. The optogenetic mutagenesis expands the toolbox for forward genetic screening and also provides direct evidence that nuclear ROS can induce heritable and specific genetic mutations. PMID:26632265

Mayaweckelia troglomorpha, a new subterranean amphipod species from Yucatán state, México (Amphipoda, Hadziidae)

PubMed Central

Angyal, Dorottya; Solís, Efraín Chávez; Magaña, Benjamín; Balázs, Gergely; Simoes, Nuno

2018-01-01

Abstract A detailed description of a new stygobiont species of the amphipod family Hadziidae, Mayaweckelia troglomorpha Angyal, sp. n. is given, based on material collected in four cenotes of Yucatán federal state, México. Morphology was studied under light microscopy and with scanning electron microscopy. Morphological description is complemented with mitochondrial cytochrome c oxidase subunit I (COI) sequences as barcodes, with affinities to the related taxa and with notes on the species’ ecology. Using COI Bayesian inference and genetic distance analyses, we show that the closest relative of the new species is M. cenoticola, forming a monophyletic group referring to the genus Mayaweckelia. Based on the available sequences, we also revealed that Mayaweckelia and Tuluweckelia are sister genera, standing close to the third Yucatán subterranean genus, Bahadzia. The data gathered on the habitat, distribution, abundance, and ecology will contribute to the conservation planning for M. troglomorpha Angyal, sp. n. PMID:29674859

Mayaweckelia troglomorpha, a new subterranean amphipod species from Yucatán state, México (Amphipoda, Hadziidae).

PubMed

Angyal, Dorottya; Solís, Efraín Chávez; Magaña, Benjamín; Balázs, Gergely; Simoes, Nuno

2018-01-01

A detailed description of a new stygobiont species of the amphipod family Hadziidae, Mayaweckelia troglomorpha Angyal, sp. n. is given, based on material collected in four cenotes of Yucatán federal state, México. Morphology was studied under light microscopy and with scanning electron microscopy. Morphological description is complemented with mitochondrial cytochrome c oxidase subunit I (COI) sequences as barcodes, with affinities to the related taxa and with notes on the species' ecology. Using COI Bayesian inference and genetic distance analyses, we show that the closest relative of the new species is M. cenoticola , forming a monophyletic group referring to the genus Mayaweckelia . Based on the available sequences, we also revealed that Mayaweckelia and Tuluweckelia are sister genera, standing close to the third Yucatán subterranean genus, Bahadzia . The data gathered on the habitat, distribution, abundance, and ecology will contribute to the conservation planning for M. troglomorpha Angyal, sp. n.

Fanconi anemia protein, FANCG, is a phosphoprotein and is upregulated with FANCA after TNF-alpha treatment.

PubMed

Futaki, M; Watanabe, S; Kajigaya, S; Liu, J M

2001-02-23

Fanconi anemia (FA) is a genetic syndrome characterized by bone marrow failure, birth defects, and a predisposition to malignancy. At this time, six FA genes have been identified, and several gene products have been found to interact in a protein complex. FA cells appear to overexpress the proinflammatory cytokine, tumor necrosis factor-alpha (TNF-alpha). We therefore examined the effects of TNF-alpha on the regulation of FA complementation group proteins, FANCG and FANCA. We found that treatment with TNF-alpha induced FANCG protein expression. FANCA was induced concurrently with FANCG, and the FANCA/FANCG complex was increased in the nucleus following TNF-alpha treatment. Inactivation of inhibitory kappa B kinase-2 modulated the expression of FANCG. We also found that both nuclear and cytoplasmic FANCG fractions were phosphorylated. These results show that FANCG is a phosphoprotein and suggest that the cellular accumulation of FA proteins is subject to regulation by TNF-alpha signaling.

FANCA Gene Mutations with 8 Novel Molecular Changes in Indian Fanconi Anemia Patients.

PubMed

Solanki, Avani; Mohanty, Purvi; Shukla, Pallavi; Rao, Anita; Ghosh, Kanjaksha; Vundinti, Babu Rao

2016-01-01

Fanconi anemia (FA), a rare heterogeneous genetic disorder, is known to be associated with 19 genes and a spectrum of clinical features. We studied FANCA molecular changes in 34 unrelated and 2 siblings of Indian patients with FA and have identified 26 different molecular changes of FANCA gene, of which 8 were novel mutations (a small deletion c.2500delC, 4 non-sense mutations c.2182C>T, c.2630C>G, c.3677C>G, c.3189G>A; and 3 missense mutations; c.1273G>C, c.3679 G>C, and c.3992 T>C). Among these only 16 patients could be assigned FA-A complementation group, because we could not confirm single exon deletions detected by MLPA or cDNA amplification by secondary confirmation method and due to presence of heterozygous non-pathogenic variations or heterozygous pathogenic mutations. An effective molecular screening strategy should be developed for confirmation of these mutations and determining the breakpoints for single exon deletions.

FANCA Gene Mutations with 8 Novel Molecular Changes in Indian Fanconi Anemia Patients

PubMed Central

Solanki, Avani; Mohanty, Purvi; Shukla, Pallavi; Rao, Anita; Ghosh, Kanjaksha; Vundinti, Babu Rao

2016-01-01

Fanconi anemia (FA), a rare heterogeneous genetic disorder, is known to be associated with 19 genes and a spectrum of clinical features. We studied FANCA molecular changes in 34 unrelated and 2 siblings of Indian patients with FA and have identified 26 different molecular changes of FANCA gene, of which 8 were novel mutations (a small deletion c.2500delC, 4 non-sense mutations c.2182C>T, c.2630C>G, c.3677C>G, c.3189G>A; and 3 missense mutations; c.1273G>C, c.3679 G>C, and c.3992 T>C). Among these only 16 patients could be assigned FA-A complementation group, because we could not confirm single exon deletions detected by MLPA or cDNA amplification by secondary confirmation method and due to presence of heterozygous non-pathogenic variations or heterozygous pathogenic mutations. An effective molecular screening strategy should be developed for confirmation of these mutations and determining the breakpoints for single exon deletions. PMID:26799702

Alpha-fetoprotein and Fanconi Anemia: Relevance to DNA Repair and Breast Cancer Susceptibility.

PubMed

Lakhi, Nisha A; Mizejewski, Gerald J

2017-02-01

Elevations of serum alpha-fetoprotein (sAFP) have been reported in fetal and infant states of anemia. Fanconi anemia (FA) belongs to a family of genetic instability disorders which lack the capability to repair DNA breaks. The lesion occurs at a checkpoint regulatory step of the G2 to mitotic transition, allowing FA cells to override cell-cycle arrest. FA DNA repair pathways contain complementation groups known as FANC proteins. FANC proteins form multi-protein complexes with BRCA proteins and are involved in homologous DNA repair. An impaired cascade in these events imparts an increased breast cancer susceptibility to female FA patients. Elevations of sAFP have availed this fetal protein to serve as a biomarker for FA disease. However, the origin of the synthesis of sAFA has not been determined in FA patients. We hypothesize that hematopoietic multipotent progenitor stem cells in the bone marrow are the source of sAFP production in FA patients.

Time to Redefine Organic Agriculture: Can’t GM Crops Be Certified as Organics?

PubMed Central

Husaini, Amjad M.; Sohail, Muhammad

2018-01-01

The challenges of sustainable food production without damaging the environment for a growing human population have increased considerably. The current agricultural practices involving chemical fertilizers and even organic farming are not sustainable in the long run and can have deleterious effects on the environment. Thus, new, innovative solutions need to be identified and propagated for tackling this. Among such innovations, that can complement conventional as well as organic farming methods, are genetic modification (GM) and aquaculture. Yet, GM technologies often face resistance from civil groups owing to an ‘unknown’ fear, akin to Frankenstein’s monster. How real is this fear? Our discussion rests on basic questions like, why can’t ‘organics’ include GM crops that do not require chemical inputs for cultivation, and can GM crops like Golden rice qualify to be ‘organic’ if cultivated through organic practices? Do we need to rethink organic agriculture in the context of the present and future challenges of 21st century? PMID:29692789

Time to Redefine Organic Agriculture: Can't GM Crops Be Certified as Organics?

PubMed

Husaini, Amjad M; Sohail, Muhammad

2018-01-01

The challenges of sustainable food production without damaging the environment for a growing human population have increased considerably. The current agricultural practices involving chemical fertilizers and even organic farming are not sustainable in the long run and can have deleterious effects on the environment. Thus, new, innovative solutions need to be identified and propagated for tackling this. Among such innovations, that can complement conventional as well as organic farming methods, are genetic modification (GM) and aquaculture. Yet, GM technologies often face resistance from civil groups owing to an 'unknown' fear, akin to Frankenstein's monster. How real is this fear? Our discussion rests on basic questions like, why can't 'organics' include GM crops that do not require chemical inputs for cultivation, and can GM crops like Golden rice qualify to be 'organic' if cultivated through organic practices? Do we need to rethink organic agriculture in the context of the present and future challenges of 21st century?

Donor Polymorphisms in Genes Related to B-Cell Biology Associated With Antibody-Mediated Rejection After Heart Transplantation.

PubMed

Marrón-Liñares, Grecia M; Núñez, Lucía; Crespo-Leiro, María G; Álvarez-López, Eloy; Barge-Caballero, Eduardo; Barge-Caballero, Gonzalo; Couto-Mallón, David; Pradas-Irun, Concepción; Muñiz, Javier; Tan, Carmela; Rodríguez, E Rene; Vázquez-Rodríguez, José Manuel; Hermida-Prieto, Manuel

2018-04-25

Heart transplantation (HT) is a well-established lifesaving treatment for endstage cardiac failure. Antibody-mediated rejection (AMR) represents one of the main problems after HT because of its diagnostic complexity and the poor evidence for supporting treatments. Complement cascade and B-cells play a key role in AMR and contribute to graft damage. This study explored the importance of variants in genes related to complement pathway and B-cell biology in HT and AMR in donors and in donor-recipient pairs.Methods and Results:Genetic variants in 112 genes (51 complement and 61 B-cell biology genes) were analyzed on next-generation sequencing in 28 donor-recipient pairs, 14 recipients with and 14 recipients without AMR. Statistical analysis was performed with SNPStats, R, and EPIDAT3.1. We identified one single nucleotide polymorphism (SNP) in donors in genes related to B-cell biology,interleukin-4 receptor subunitα (p.Ile75Val-IL4Rα), which correlated with the development of AMR. Moreover, in the analysis of recipient-donor genotype discrepancies, we identified another SNP, in this case inadenosine deaminase(ADA; p.Val178(p=)), which was related to B-cell biology, associated with the absence of AMR. Donor polymorphisms and recipient-donor discrepancies in genes related to the biology of B-cells, could have an important role in the development of AMR. In contrast, no variants in donor or in donor-recipient pairs in complement pathways seem to have an impact on AMR.

The SaeRS Two-Component System Controls Survival of Staphylococcus aureus in Human Blood through Regulation of Coagulase

PubMed Central

Guo, Haiyong; Hall, Jeffrey W.; Yang, Junshu; Ji, Yinduo

2017-01-01

The SaeRS two-component system plays important roles in regulation of key virulence factors and pathogenicity. In this study, however, we found that the deletion mutation of saeRS enhanced bacterial survival in human blood, whereas complementation of the mutant with SaeRS returned survival to wild-type levels. Moreover, these phenomena were observed in different MRSA genetic background isolates, including HA-MRSA WCUH29, CA-MRSA 923, and MW2. To elucidate which gene(s) regulated by SaeRS contribute to the effect, we conducted a series of complementation studies with selected known SaeRS target genes in trans. We found coagulase complementation abolished the enhanced survival of the SaeRS mutant in human blood. The coa and saeRS deletion mutants exhibited a similar survival phenotype in blood. Intriguingly, heterologous expression of coagulase decreased survival of S. epidermidis in human blood. Further, the addition of recombinant coagulase to blood significantly decreased the survival of S. aureus. Further, analysis revealed staphylococcal resistance to killing by hydrogen peroxide was partially dependent on the presence or absence of coagulase. Furthermore, complementation with coagulase, but not SaeRS, returned saeRS/coa double mutant survival in blood to wild-type levels. These data indicate SaeRS modulates bacterial survival in blood in coagulase-dependent manner. Our results provide new insights into the role of staphylococcal SaeRS and coagulase on bacterial survival in human blood. PMID:28611950

Expression of Human Complement Factor H Prevents Age-Related Macular Degeneration–Like Retina Damage and Kidney Abnormalities in Aged Cfh Knockout Mice

PubMed Central

Ding, Jin-Dong; Kelly, Una; Landowski, Michael; Toomey, Christopher B.; Groelle, Marybeth; Miller, Chelsey; Smith, Stephanie G.; Klingeborn, Mikael; Singhapricha, Terry; Jiang, Haixiang; Frank, Michael M.; Bowes Rickman, Catherine

2016-01-01

Complement factor H (CFH) is an important regulatory protein in the alternative pathway of the complement system, and CFH polymorphisms increase the genetic risk of age-related macular degeneration dramatically. These same human CFH variants have also been associated with dense deposit disease. To mechanistically study the function of CFH in the pathogenesis of these diseases, we created transgenic mouse lines using human CFH bacterial artificial chromosomes expressing full-length human CFH variants and crossed these to Cfh knockout (Cfh−/−) mice. Human CFH protein inhibited cleavage of mouse complement component 3 and factor B in plasma and in retinal pigment epithelium/choroid/sclera, establishing that human CFH regulates activation of the mouse alternative pathway. One of the mouse lines, which express relatively higher levels of CFH, demonstrated functional and structural protection of the retina owing to the Cfh deletion. Impaired visual function, detected as a deficit in the scotopic electroretinographic response, was improved in this transgenic mouse line compared with Cfh−/− mice, and transgenics had a thicker outer nuclear layer and less sub–retinal pigment epithelium deposit accumulation. In addition, expression of human CFH also completely protected the mice from developing kidney abnormalities associated with loss of CFH. These humanized CFH mice present a valuable model for study of the molecular mechanisms of age-related macular degeneration and dense deposit disease and for testing therapeutic targets. PMID:25447048

The alternative complement component factor B regulates UV-induced oedema, systemic suppression of contact and delayed hypersensitivity, and mast cell infiltration into the skin.

PubMed

Byrne, Scott N; Hammond, Kirsten J L; Chan, Carling Y-Y; Rogers, Linda J; Beaugie, Clare; Rana, Sabita; Marsh-Wakefield, Felix; Thurman, Joshua M; Halliday, Gary M

2015-04-01

Ultraviolet (UV) wavelengths in sunlight are the prime cause of skin cancer in humans with both the UVA and UVB wavebands making a contribution to photocarcinogenesis. UV has many different biological effects on the skin that contribute to carcinogenesis, including suppression of adaptive immunity, sunburn and altering the migration of mast cells into and away from irradiated skin. Many molecular mechanisms have been identified as contributing to skin responses to UV. Recently, using gene set enrichment analysis of microarray data, we identified the alternative complement pathway with a central role for factor B (fB) in UVA-induced immunosuppression. In the current study we used mice genetically deficient in fB (fB-/- mice) to study the functional role of the alternative complement pathway in skin responses to UV. We found that fB is required for not only UVA but also UVB-induced immunosuppression and solar-simulated UV induction of the oedemal component of sunburn. Factor B-/- mice had a larger number of resident skin mast cells than control mice, but unlike the controls did not respond to UV by increasing mast cell infiltration into the skin. This study provides evidence for a function role for fB in skin responses to UV radiation. Factor B regulates UVA and UVB induced immunosuppression, UV induced oedema and mast cell infiltration into the skin. The alternative complement pathway is therefore an important regulator of skin responses to UV.

Protein domains connect cell cycle stimulation directly to initiation of DNA replication.

PubMed Central

Gjørup, O V; Rose, P E; Holman, P S; Bockus, B J; Schaffhausen, B S

1994-01-01

Polyoma large T antigen (LT) is the only viral gene product required for viral DNA replication. LT can be divided into two domains, one N-terminal (NT) spanning residues 1-260 and one C-terminal (CT) comprising approximately residues 264-785. NT is known to immortalize primary cells in a manner dependent on binding of pRB/p107. Here a CT construct comprising residues 264-785 was shown to have independent function in DNA replication. CT is entirely sufficient for driving viral DNA replication in vivo in growing mouse cells at a level approaching that of full-length LT. In contrast, CT is strikingly deficient for replication in serum-starved cells. However, this deficiency can be complemented by coexpression of NT. BrdUrd incorporation in transfected, starved cells showed that NT was sufficient for inducing S phase, suggesting a mechanism for complementation. By contrast, CT was unable to induce S phase when tested in the same assay. NT also promotes phosphorylation of sites in CT that are likely to be important for replication. Other DNA tumor virus gene products such as adenovirus E1A 12S and human papillomavirus 16 E7 could also complement CT for replication. Although NT, E1A 12S, and E7 all bind the retinoblastoma gene product (pRB) and p107, genetic analysis demonstrates an additional function, independent of that binding, is responsible for complementation. Images PMID:7991595

Transposable Element Genomic Fissuring in Pyrenophora teres Is Associated With Genome Expansion and Dynamics of Host–Pathogen Genetic Interactions

PubMed Central

Syme, Robert A.; Martin, Anke; Wyatt, Nathan A.; Lawrence, Julie A.; Muria-Gonzalez, Mariano J.; Friesen, Timothy L.; Ellwood, Simon R.

2018-01-01

Pyrenophora teres, P. teres f. teres (PTT) and P. teres f. maculata (PTM) cause significant diseases in barley, but little is known about the large-scale genomic differences that may distinguish the two forms. Comprehensive genome assemblies were constructed from long DNA reads, optical and genetic maps. As repeat masking in fungal genomes influences the final gene annotations, an accurate and reproducible pipeline was developed to ensure comparability between isolates. The genomes of the two forms are highly collinear, each composed of 12 chromosomes. Genome evolution in P. teres is characterized by genome fissuring through the insertion and expansion of transposable elements (TEs), a process that isolates blocks of genic sequence. The phenomenon is particularly pronounced in PTT, which has a larger, more repetitive genome than PTM and more recent transposon activity measured by the frequency and size of genome fissures. PTT has a longer cultivated host association and, notably, a greater range of host–pathogen genetic interactions compared to other Pyrenophora spp., a property which associates better with genome size than pathogen lifestyle. The two forms possess similar complements of TE families with Tc1/Mariner and LINE-like Tad-1 elements more abundant in PTT. Tad-1 was only detectable as vestigial fragments in PTM and, within the forms, differences in genome sizes and the presence and absence of several TE families indicated recent lineage invasions. Gene differences between P. teres forms are mainly associated with gene-sparse regions near or within TE-rich regions, with many genes possessing characteristics of fungal effectors. Instances of gene interruption by transposons resulting in pseudogenization were detected in PTT. In addition, both forms have a large complement of secondary metabolite gene clusters indicating significant capacity to produce an array of different molecules. This study provides genomic resources for functional genetics to help dissect factors underlying the host–pathogen interactions. PMID:29720997

Genetic predisposition for adult lactose intolerance and relation to diet, bone density, and bone fractures.

PubMed

Obermayer-Pietsch, Barbara M; Bonelli, Christine M; Walter, Daniela E; Kuhn, Regina J; Fahrleitner-Pammer, Astrid; Berghold, Andrea; Goessler, Walter; Stepan, Vinzenz; Dobnig, Harald; Leb, Georg; Renner, Wilfried

2004-01-01

Evidence that genetic disposition for adult lactose intolerance significantly affects calcium intake, bone density, and fractures in postmenopausal women is presented. PCR-based genotyping of lactase gene polymorphisms may complement diagnostic procedures to identify persons at risk for both lactose malabsorption and osteoporosis. Lactase deficiency is a common autosomal recessive condition resulting in decreased intestinal lactose degradation. A -13910 T/C dimorphism (LCT) near the lactase phlorizin hydrolase gene, reported to be strongly associated with adult lactase nonpersistence, may have an impact on calcium supply, bone density, and osteoporotic fractures in the elderly. We determined LCT genotypes TT, TC, and CC in 258 postmenopausal women using a polymerase chain reaction-based assay. Genotypes were related to milk intolerance, nutritional calcium intake, intestinal calcium absorption, bone mineral density (BMD), and nonvertebral fractures. Twenty-four percent of all women were found to have CC genotypes and genetic lactase deficiency. Age-adjusted BMD at the hip in CC genotypes and at the spine in CC and TC genotypes was reduced by -7% to -11% depending on the site measured (p = 0.04). LCT(T/C-13910) polymorphisms alone accounted for 2-4% of BMD in a multiple regression model. Bone fracture incidence was significantly associated with CC genotypes (p = 0.001). Milk calcium intake was significantly lower (-55%, p = 0.004) and aversion to milk consumption was significantly higher (+166%, p = 0.01) in women with the CC genotype, but there were no differences in overall dietary calcium intake or in intestinal calcium absorption test values. The LCT(T/C-13910) polymorphism is associated with subjective milk intolerance, reduced milk calcium intake, and reduced BMD at the hip and the lumbar spine and may predispose to bone fractures. Genetic testing for lactase deficiency may complement indirect methods in the detection of individuals at risk for both lactose malabsorption and osteoporosis.

AmpliSeq Screening of Genes Encoding the C-Type Lectin Receptors and Their Signaling Components Reveals a Common Variant in MASP1 Associated with Pulmonary Tuberculosis in an Indian Population.

PubMed

Klassert, Tilman E; Goyal, Surabhi; Stock, Magdalena; Driesch, Dominik; Hussain, Abid; Berrocal-Almanza, Luis Carlos; Myakala, Rajashekar; Sumanlatha, Gaddam; Valluri, Vijayalakshmi; Ahmed, Niyaz; Schumann, Ralf R; Flores, Carlos; Slevogt, Hortense

2018-01-01

Tuberculosis (TB) is a multifactorial disease governed by bacterial, host and environmental factors. On the host side, growing evidence shows the crucial role that genetic variants play in the susceptibility to Mycobacterium tuberculosis (Mtb) infection. Such polymorphisms have been described in genes encoding for different cytokines and pattern recognition receptors (PRR), including numerous Toll-like receptors (TLRs). In recent years, several members of the C-type lectin receptors (CTLRs) have been identified as key PRRs in TB pathogenesis. Nevertheless, studies to date have only addressed particular genetic polymorphisms in these receptors or their related pathways in relation with TB. In the present study, we screened the main CTLR gene clusters as well as CTLR pathway-related genes for genetic variation associated with pulmonary tuberculosis (PTB). This case-control study comprised 144 newly diagnosed pulmonary TB patients and 181 healthy controls recruited at the Bhagwan Mahavir Medical Research Center (BMMRC), Hyderabad, India. A two-stage study was employed in which an explorative AmpliSeq-based screening was followed by a validation phase using iPLEX MassARRAY. Our results revealed one SNP (rs3774275) in MASP1 significantly associated with PTB in our population (joint analysis p  = 0.0028). Furthermore, serum levels of MASP1 were significantly elevated in TB patients when compared to healthy controls. Moreover, in the present study we could observe an impact of increased MASP1 levels on the lectin pathway complement activity in vitro . In conclusion, our results demonstrate a significant association of MASP1 polymorphism rs3774275 and MASP1 serum levels with the development of pulmonary TB. The present work contributes to our understanding of host-Mtb interaction and reinforces the critical significance of mannose-binding lectin and the lectin-complement pathway in Mtb pathogenesis. Moreover, it proposes a MASP1 polymorphism as a potential genetic marker for TB resistance.

AmpliSeq Screening of Genes Encoding the C-Type Lectin Receptors and Their Signaling Components Reveals a Common Variant in MASP1 Associated with Pulmonary Tuberculosis in an Indian Population

PubMed Central

Klassert, Tilman E.; Goyal, Surabhi; Stock, Magdalena; Driesch, Dominik; Hussain, Abid; Berrocal-Almanza, Luis Carlos; Myakala, Rajashekar; Sumanlatha, Gaddam; Valluri, Vijayalakshmi; Ahmed, Niyaz; Schumann, Ralf R.; Flores, Carlos; Slevogt, Hortense

2018-01-01

Tuberculosis (TB) is a multifactorial disease governed by bacterial, host and environmental factors. On the host side, growing evidence shows the crucial role that genetic variants play in the susceptibility to Mycobacterium tuberculosis (Mtb) infection. Such polymorphisms have been described in genes encoding for different cytokines and pattern recognition receptors (PRR), including numerous Toll-like receptors (TLRs). In recent years, several members of the C-type lectin receptors (CTLRs) have been identified as key PRRs in TB pathogenesis. Nevertheless, studies to date have only addressed particular genetic polymorphisms in these receptors or their related pathways in relation with TB. In the present study, we screened the main CTLR gene clusters as well as CTLR pathway-related genes for genetic variation associated with pulmonary tuberculosis (PTB). This case-control study comprised 144 newly diagnosed pulmonary TB patients and 181 healthy controls recruited at the Bhagwan Mahavir Medical Research Center (BMMRC), Hyderabad, India. A two-stage study was employed in which an explorative AmpliSeq-based screening was followed by a validation phase using iPLEX MassARRAY. Our results revealed one SNP (rs3774275) in MASP1 significantly associated with PTB in our population (joint analysis p = 0.0028). Furthermore, serum levels of MASP1 were significantly elevated in TB patients when compared to healthy controls. Moreover, in the present study we could observe an impact of increased MASP1 levels on the lectin pathway complement activity in vitro. In conclusion, our results demonstrate a significant association of MASP1 polymorphism rs3774275 and MASP1 serum levels with the development of pulmonary TB. The present work contributes to our understanding of host-Mtb interaction and reinforces the critical significance of mannose-binding lectin and the lectin-complement pathway in Mtb pathogenesis. Moreover, it proposes a MASP1 polymorphism as a potential genetic marker for TB resistance. PMID:29515573

Complement factor H Y402H variant and risk of age-related macular degeneration in Asians: a systematic review and meta-analysis.

PubMed

Kondo, Naoshi; Bessho, Hiroaki; Honda, Shigeru; Negi, Akira

2011-02-01

To investigate whether the Y402H variant in the complement factor H gene is associated with age-related macular degeneration (AMD) in Asian populations. Meta-analysis of previous publications. Case-control groups of subjects with AMD and controls from 13 association studies. We performed a meta-analysis of the association between Y402H and AMD in Asian populations using data available from 13 case-control studies involving 3973 subjects. Summary odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using fixed- and random-effects models. The Q-statistic test was used to assess heterogeneity, and Egger's test was used to evaluate publication bias. Sensitivity analysis, cumulative meta-analysis, and meta-regression analysis were also performed. Allele and genotype frequencies of the Y402H variant. The Y402H variant showed a significant summary OR of 1.97 (95% CI, 1.54-2.52; P<0.001; allelic contrast model) per allele. Possession of at least 1 copy of the C allele increased the disease risk by 1.97-fold (95% CI, 1.63-2.39; P<0.001; dominant model) and accounted for 8.8% of the attributable risk of AMD in Asian populations. Sensitivity analysis indicated the robustness of our findings, and evidence of publication bias was not observed in our meta-analysis. Meta-regression analysis indicated no significant effect of baseline study characteristics on the summary effect size. Cumulative meta-analysis revealed that the summary ORs were stable and the 95% CIs narrowed with the accumulation of data over time. Our analysis provides substantial evidence that the Y402H variant is significantly associated with AMD in Asian populations. Our results expand the number of confirmed AMD susceptibility loci for Asians populations, which provide a better understanding of the genetic architecture underlying disease susceptibility and may advance the potential for preclinical prediction in future genetic tests by a combined evaluation of inherited susceptibility with previously established loci. Copyright © 2011 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Range expansion of heterogeneous populations.

PubMed

Reiter, Matthias; Rulands, Steffen; Frey, Erwin

2014-04-11

Risk spreading in bacterial populations is generally regarded as a strategy to maximize survival. Here, we study its role during range expansion of a genetically diverse population where growth and motility are two alternative traits. We find that during the initial expansion phase fast-growing cells do have a selective advantage. By contrast, asymptotically, generalists balancing motility and reproduction are evolutionarily most successful. These findings are rationalized by a set of coupled Fisher equations complemented by stochastic simulations.

Contrasting Complement Control, Temporal Adjunct Control and Controlled Verbal Gerund Subjects in ASD: The Role of Contextual Cues in Reference Assignment.

PubMed

Janke, Vikki; Perovic, Alexandra

2017-01-01

This study examines two complex syntactic dependencies (complement control and sentence-final temporal adjunct control) and one pragmatic dependency (controlled verbal gerund subjects) in children with ASD. Sixteen high-functioning (HFA) children (aged 6-16) with a diagnosis of autism and no language impairment, matched on age, gender and non-verbal MA to one TD control group, and on age, gender and verbal MA to another TD control group, undertook three picture-selection tasks. Task 1 measured their base-line interpretations of the empty categories ( ec ). Task 2 preceded these sentence sets with a weakly established topic cueing an alternative referent and Task 3 with a strongly established topic cueing an alternative referent. In complement control (Ron persuaded Hermione ec to kick the ball) and sentence-final temporal adjunct control (Harry tapped Luna while ec feeding the owl), the reference of the ec is argued to be related obligatorily to the object and subject respectively. In controlled verbal-gerund subjects (VGS) ( ec Rowing the boat clumsily made Luna seasick), the ec 's reference is resolved pragmatically. Referent choices across the three tasks were compared. TD children chose the object uniformly in complement control across all tasks but in adjunct control, preferences shifted toward the object in Task 3. In controlled VGSs, they exhibited a strong preference for an internal-referent interpretation in Task 1, which shifted in the direction of the cues in Tasks 2 and 3. HFA children gave a mixed performance. They patterned with their TD counterparts on complement control and controlled VGSs but performed marginally differently on adjunct control: no TD groups were influenced by the weakly established topic in Task 2 but all groups were influenced by the strongly established topic in Task 3. HFA children were less influenced than the TD children, resulting in their making fewer object choices overall but revealing parallel patterns of performance. In this first study of three sub-types of control in ASD, we demonstrate that HFA children consult the same pragmatic cues to the same degree as TD children, in spite of the diverse pragmatic deficits reported for this population.

Contrasting Complement Control, Temporal Adjunct Control and Controlled Verbal Gerund Subjects in ASD: The Role of Contextual Cues in Reference Assignment

PubMed Central

Janke, Vikki; Perovic, Alexandra

2017-01-01

This study examines two complex syntactic dependencies (complement control and sentence-final temporal adjunct control) and one pragmatic dependency (controlled verbal gerund subjects) in children with ASD. Sixteen high-functioning (HFA) children (aged 6–16) with a diagnosis of autism and no language impairment, matched on age, gender and non-verbal MA to one TD control group, and on age, gender and verbal MA to another TD control group, undertook three picture-selection tasks. Task 1 measured their base-line interpretations of the empty categories (ec). Task 2 preceded these sentence sets with a weakly established topic cueing an alternative referent and Task 3 with a strongly established topic cueing an alternative referent. In complement control (Ron persuaded Hermione ec to kick the ball) and sentence-final temporal adjunct control (Harry tapped Luna while ec feeding the owl), the reference of the ec is argued to be related obligatorily to the object and subject respectively. In controlled verbal-gerund subjects (VGS) (ec Rowing the boat clumsily made Luna seasick), the ec's reference is resolved pragmatically. Referent choices across the three tasks were compared. TD children chose the object uniformly in complement control across all tasks but in adjunct control, preferences shifted toward the object in Task 3. In controlled VGSs, they exhibited a strong preference for an internal-referent interpretation in Task 1, which shifted in the direction of the cues in Tasks 2 and 3. HFA children gave a mixed performance. They patterned with their TD counterparts on complement control and controlled VGSs but performed marginally differently on adjunct control: no TD groups were influenced by the weakly established topic in Task 2 but all groups were influenced by the strongly established topic in Task 3. HFA children were less influenced than the TD children, resulting in their making fewer object choices overall but revealing parallel patterns of performance. In this first study of three sub-types of control in ASD, we demonstrate that HFA children consult the same pragmatic cues to the same degree as TD children, in spite of the diverse pragmatic deficits reported for this population. PMID:28400743

Classical Complement Pathway Activation in the Kidneys of Women With Preeclampsia.

PubMed

Penning, Marlies; Chua, Jamie S; van Kooten, Cees; Zandbergen, Malu; Buurma, Aletta; Schutte, Joke; Bruijn, Jan Anthonie; Khankin, Eliyahu V; Bloemenkamp, Kitty; Karumanchi, S Ananth; Baelde, Hans

2015-07-01

A growing body of evidence suggests that complement dysregulation plays a role in the pathogenesis of preeclampsia. The kidney is one of the major organs affected in preeclampsia. Because the kidney is highly susceptible to complement activation, we hypothesized that preeclampsia is associated with renal complement activation. We performed a nationwide search for renal autopsy material in the Netherlands using a computerized database (PALGA). Renal tissue was obtained from 11 women with preeclampsia, 25 pregnant controls, and 14 nonpregnant controls with hypertension. The samples were immunostained for C4d, C1q, mannose-binding lectin, properdin, C3d, C5b-9, IgA, IgG, and IgM. Preeclampsia was significantly associated with renal C4d-a stable marker of complement activation-and the classical pathway marker C1q. In addition, the prevalence of IgM was significantly higher in the kidneys of the preeclamptic women. No other complement markers studied differed between the groups. Our findings in human samples were validated using a soluble fms-like tyrosine kinase 1 mouse model of preeclampsia. The kidneys in the soluble fms-like tyrosine kinase 1-injected mice had significantly more C4 deposits than the control mice. The association between preeclampsia and renal C4d, C1q, and IgM levels suggests that the classical complement pathway is involved in the renal injury in preeclampsia. Moreover, our finding that soluble fms-like tyrosine kinase 1-injected mice develop excess C4 deposits indicates that angiogenic dysregulation may play a role in complement activation within the kidney. We suggest that inhibiting complement activation may be beneficial for preventing the renal manifestations of preeclampsia. © 2015 American Heart Association, Inc.

DNA Damage Induced by Alkylating Agents and Repair Pathways

PubMed Central

Kondo, Natsuko; Takahashi, Akihisa; Ono, Koji; Ohnishi, Takeo

2010-01-01

The cytotoxic effects of alkylating agents are strongly attenuated by cellular DNA repair processes, necessitating a clear understanding of the repair mechanisms. Simple methylating agents form adducts at N- and O-atoms. N-methylations are removed by base excision repair, AlkB homologues, or nucleotide excision repair (NER). O6-methylguanine (MeG), which can eventually become cytotoxic and mutagenic, is repaired by O6-methylguanine-DNA methyltransferase, and O6MeG:T mispairs are recognized by the mismatch repair system (MMR). MMR cannot repair the O6MeG/T mispairs, which eventually lead to double-strand breaks. Bifunctional alkylating agents form interstrand cross-links (ICLs) which are more complex and highly cytotoxic. ICLs are repaired by complex of NER factors (e.g., endnuclease xeroderma pigmentosum complementation group F-excision repair cross-complementing rodent repair deficiency complementation group 1), Fanconi anemia repair, and homologous recombination. A detailed understanding of how cells cope with DNA damage caused by alkylating agents is therefore potentially useful in clinical medicine. PMID:21113301

Experimental test of dense wavelength-division multiplexing using novel, periodic-group-delay-complemented dispersion compensation and dispersion-managed solitons

NASA Astrophysics Data System (ADS)

Mollenauer, Linn F.; Grant, Andrew; Liu, Xiang; Wei, Xing; Xie, Chongjin; Kang, Inuk

2003-11-01

In an all-Raman amplified, recirculating loop containing 100-km spans, we have tested dense wavelength-division multiplexing at 10 Gbits/s per channel, using dispersion-managed solitons and a novel, periodic-group-delay-complemented dispersion-compensation scheme that greatly reduces the timing jitter from interchannel collisions. The achieved working distances are ~9000 and ~20,000 km for uncorrected bit error rates of <10-8 and <10-3, respectively, the latter corresponding to the use of ``enhanced'' forward error correction; significantly, these distances are very close to those achievable in single-channel transmission in the same system.

Dynamic labelling of neural connections in multiple colours by trans-synaptic fluorescence complementation

PubMed Central

Macpherson, Lindsey J.; Zaharieva, Emanuela E.; Kearney, Patrick J.; Alpert, Michael H.; Lin, Tzu-Yang; Turan, Zeynep; Lee, Chi-Hon; Gallio, Marco

2015-01-01

Determining the pattern of activity of individual connections within a neural circuit could provide insights into the computational processes that underlie brain function. Here, we develop new strategies to label active synapses by trans-synaptic fluorescence complementation in Drosophila. First, we demonstrate that a synaptobrevin-GRASP chimera functions as a powerful activity-dependent marker for synapses in vivo. Next, we create cyan and yellow variants, achieving activity-dependent, multi-colour fluorescence reconstitution across synapses (X-RASP). Our system allows for the first time retrospective labelling of synapses (rather than whole neurons) based on their activity, in multiple colours, in the same animal. As individual synapses often act as computational units in the brain, our method will promote the design of experiments that are not possible using existing techniques. Moreover, our strategies are easily adaptable to circuit mapping in any genetic system. PMID:26635273

Steroids and triterpenes from the fruit bodies of Ganoderma lucidum and their anti-complement activity.

PubMed

Seo, Hyo Won; Hung, Tran Manh; Na, MinKyun; Jung, Hyun Ju; Kim, Jin Cheol; Choi, Jae Sue; Kim, Jung Hee; Lee, Hyeong-Kyu; Lee, IkSoo; Bae, KiHwan; Hattori, Masao; Min, Byung Sun

2009-11-01

To determine the anti-complement activity of natural triterpenes, chromatographic separation of the EtOAc-soluble fraction from the fruiting body of Ganoderma lucidum led to the isolation of three steroids and five triterpenoids. They were identified as ergosterol peroxide (1), ergosterol (2), genoderic acid Sz (3), stella sterol (4), ganoderic aic C1 (5), ganoderic acid A (6), methyl ganoderate A (7), and lucidenic acid A (8) based on spectroscopic evidence and physicochemical properties. These compounds were examined for their anti-complement activity against the classical pathway of the complement system. Compounds 2 and 3 showed potent anti-complement activity with IC50 values of 52.0 and 44.6 microM, respectively. Compound 1 exhibited significant inhibitory activity with an IC50 value of 126.8 microM, whereas compounds 4-8 were inactive. Our findings suggested that in addition to the ketone group at C-3, the delta7(8), delta9(11)-lanostadiene type triterpene also plays an important role in inhibiting the hemolytic activity of human serum against erythrocytes.

Methods for determining the genetic affinity of microorganisms and viruses

NASA Technical Reports Server (NTRS)

Fox, George E. (Inventor); Willson, III, Richard C. (Inventor); Zhang, Zhengdong (Inventor)

2012-01-01

Selecting which sub-sequences in a database of nucleic acid such as 16S rRNA are highly characteristic of particular groupings of bacteria, microorganisms, fungi, etc. on a substantially phylogenetic tree. Also applicable to viruses comprising viral genomic RNA or DNA. A catalogue of highly characteristic sequences identified by this method is assembled to establish the genetic identity of an unknown organism. The characteristic sequences are used to design nucleic acid hybridization probes that include the characteristic sequence or its complement, or are derived from one or more characteristic sequences. A plurality of these characteristic sequences is used in hybridization to determine the phylogenetic tree position of the organism(s) in a sample. Those target organisms represented in the original sequence database and sufficient characteristic sequences can identify to the species or subspecies level. Oligonucleotide arrays of many probes are especially preferred. A hybridization signal can comprise fluorescence, chemiluminescence, or isotopic labeling, etc.; or sequences in a sample can be detected by direct means, e.g. mass spectrometry. The method's characteristic sequences can also be used to design specific PCR primers. The method uniquely identifies the phylogenetic affinity of an unknown organism without requiring prior knowledge of what is present in the sample. Even if the organism has not been previously encountered, the method still provides useful information about which phylogenetic tree bifurcation nodes encompass the organism.

The TRANSPARENT TESTA16 Locus Encodes the ARABIDOPSIS BSISTER MADS Domain Protein and Is Required for Proper Development and Pigmentation of the Seed Coat

PubMed Central

Nesi, Nathalie; Debeaujon, Isabelle; Jond, Clarisse; Stewart, Amanda J.; Jenkins, Gareth I.; Caboche, Michel; Lepiniec, Loïc

2002-01-01

Screening for seed pigmentation phenotypes in Arabidopsis led to the isolation of three allelic yellow-seeded mutants, which defined the novel TRANSPARENT TESTA16 (TT16) locus. Cloning of TT16 was performed by T-DNA tagging and confirmed by genetic complementation and sequencing of two mutant alleles. TT16 encodes the ARABIDOPSIS BSISTER (ABS) MADS domain protein. ABS belongs to the recently identified “B-sister” (BS) clade, which contains genes of unknown function that are expressed mainly in female organs. Phylogenetic analyses using a maximum parsimony approach confirmed that TT16/ABS and related proteins form a monophyletic group. TT16/ABS was expressed mainly in the ovule, as are the other members of the BS clade. TT16/ABS is necessary for BANYULS expression and proanthocyanidin accumulation in the endothelium of the seed coat, with the exception of the chalazal-micropylar area. In addition, mutant phenotype and ectopic expression analyses suggested that TT16/ABS also is involved in the specification of endothelial cells. Nevertheless, TT16/ABS apparently is not required for proper ovule function. We report the functional characterization of a member of the BS MADS box gene subfamily, demonstrating its involvement in endothelial cell specification as well as in the increasingly complex genetic control of flavonoid biosynthesis in the Arabidopsis seed coat. PMID:12368498

Diversity, virulence, and antimicrobial resistance of the KPC-producing Klebsiella pneumoniae ST307 clone

PubMed Central

Villa, Laura; Feudi, Claudia; Fortini, Daniela; Brisse, Sylvain; Passet, Virginie; Bonura, Celestino; Endimiani, Andrea; Mammina, Caterina; Ocampo, Ana Maria; Jimenez, Judy Natalia; Doumith, Michel; Woodford, Neil; Hopkins, Katie

2017-01-01

The global spread of Klebsiella pneumoniae producing Klebsiella pneumoniae carbapenemase (KPC) has been mainly associated with the dissemination of high-risk clones. In the last decade, hospital outbreaks involving KPC-producing K. pneumoniae have been predominantly attributed to isolates belonging to clonal group (CG) 258. However, results of recent epidemiological analysis indicate that KPC-producing sequence type (ST) 307, is emerging in different parts of the world and is a candidate to become a prevalent high-risk clone in the near future. Here we show that the ST307 genome encodes genetic features that may provide an advantage in adaptation to the hospital environment and the human host. Sequence analysis revealed novel plasmid-located virulence factors, including a cluster for glycogen synthesis. Glycogen production is considered to be one of the possible adaptive responses to long-term survival and growth in environments outside the host. Chromosomally-encoded virulence traits in the clone comprised fimbriae, an integrative conjugative element carrying the yersiniabactin siderophore, and two different capsular loci. Compared with the ST258 clone, capsulated ST307 isolates showed higher resistance to complement-mediated killing. The acquired genetic features identified in the genome of this new emerging clone may contribute to increased persistence of ST307 in the hospital environment and shed light on its potential epidemiological success. PMID:28785421

Origin and diversification of the basic helix-loop-helix gene family in metazoans: insights from comparative genomics

PubMed Central

Simionato, Elena; Ledent, Valérie; Richards, Gemma; Thomas-Chollier, Morgane; Kerner, Pierre; Coornaert, David; Degnan, Bernard M; Vervoort, Michel

2007-01-01

Background Molecular and genetic analyses conducted in model organisms such as Drosophila and vertebrates, have provided a wealth of information about how networks of transcription factors control the proper development of these species. Much less is known, however, about the evolutionary origin of these elaborated networks and their large-scale evolution. Here we report the first evolutionary analysis of a whole superfamily of transcription factors, the basic helix-loop-helix (bHLH) proteins, at the scale of the whole metazoan kingdom. Results We identified in silico the putative full complement of bHLH genes in the sequenced genomes of 12 different species representative of the main metazoan lineages, including three non-bilaterian metazoans, the cnidarians Nematostella vectensis and Hydra magnipapillata and the demosponge Amphimedon queenslandica. We have performed extensive phylogenetic analyses of the 695 identified bHLHs, which has allowed us to allocate most of these bHLHs to defined evolutionary conserved groups of orthology. Conclusion Three main features in the history of the bHLH gene superfamily can be inferred from these analyses: (i) an initial diversification of the bHLHs has occurred in the pre-Cambrian, prior to metazoan cladogenesis; (ii) a second expansion of the bHLH superfamily occurred early in metazoan evolution before bilaterians and cnidarians diverged; and (iii) the bHLH complement during the evolution of the bilaterians has been remarkably stable. We suggest that these features may be extended to other developmental gene families and reflect a general trend in the evolution of the developmental gene repertoires of metazoans. PMID:17335570

The practical and pedagogical advantages of an ambigraphic nucleic acid notation.

PubMed

Rozak, David A

2006-01-01

The universally applied IUPAC notation for nucleic acids was adopted primarily to facilitate the mental association of G, A, T, C, and the related ambiguity characters with the bases they represent. However it is possible to create a notation that offers greater support for the basic manipulations and analyses to which genetic sequences frequently are subjected. By designing a nucleic acid notation around ambigrams, it is possible to simplify the frequently applied process of reverse complementation and aid the visualization of palindromes. The ambigraphic notation presented here also uses common orthographic features such as stems and loops to highlight guanine and cytosine rich regions, support the derivation of ambiguity characters, and aid educators in teaching the fundamentals of molecular genetics.

Scarless genome editing and stable inducible expression vectors for Geobacter sulfurreducens

DOE PAGES

Chan, Chi Ho; Levar, Caleb E.; Zacharoff, Lori; ...

2015-08-07

Metal reduction by members of the Geobacteraceae is encoded by multiple gene clusters, and the study of extracellular electron transfer often requires biofilm development on surfaces. Genetic tools that utilize polar antibiotic cassette insertions limit mutant construction and complementation. In addition, unstable plasmids create metabolic burdens that slow growth, and the presence of antibiotics such as kanamycin can interfere with the rate and extent of Geobacter biofilm growth. We report here genetic system improvements for the model anaerobic metal-reducing bacterium Geobacter sulfurreducens. A motile strain of G. sulfurreducens was constructed by precise removal of a transposon interrupting the fgrM flagellarmore » regulator gene using SacB/sucrose counterselection, and Fe(III) citrate reduction was eliminated by deletion of the gene encoding the inner membrane cytochrome imcH. We also show that RK2-based plasmids were maintained in G. sulfurreducens for over 15 generations in the absence of antibiotic selection in contrast to unstable pBBR1 plasmids. Therefore, we engineered a series of new RK2 vectors containing native constitutive Geobacter promoters, and modified one of these promoters for VanR-dependent induction by the small aromatic carboxylic acid vanillate. Inducible plasmids fully complemented Δ imcH mutants for Fe(III) reduction, Mn(IV) oxide reduction, and growth on poised electrodes. A real-time, high-throughput Fe(III) citrate reduction assay is described that can screen numerous G. sulfurreducens strain constructs simultaneously and shows the sensitivity of imcH expression by the vanillate system. Lastly, these tools will enable more sophisticated genetic studies in G. sulfurreducens without polar insertion effects or need for multiple antibiotics.« less

BAPJ69-4A: a yeast two-hybrid strain for both positive and negative genetic selection.

PubMed

Shaffer, Hally Anne; Rood, Michael Kenneth; Kashlan, Badar; Chang, Eileen I-ling; Doyle, Donald Francis; Azizi, Bahareh

2012-10-01

Genetic selection systems, such as the yeast two-hybrid system, are efficient methods to detect protein-protein and protein-ligand interactions. These systems have been further developed to assess negative interactions, such as inhibition, using the URA3 genetic selection marker. Previously, chemical complementation was used to assess positive selection in Saccharomyces cerevisiae. In this work, a new S. cerevisiae strain, called BAPJ69-4A, containing three selective markers ADE2, HIS3, and URA3 as well as the lacZ gene controlled by Gal4 response elements, was developed and characterized using the retinoid X receptor (RXR) and its ligand 9-cis retinoic acid (9cRA). Further characterization was performed using RXR variants and the synthetic ligand LG335. To assess the functionality of the strain, RXR was compared to the parent strain PJ69-4A in adenine, histidine, and uracil selective media. In positive selection, associating partners that lead to cell growth were observed in all media in the presence of ligand, whereas partners that did not associate due to the absence of ligand displayed no growth. Conversely, in negative selection, partners that did not associate in 5-FOA medium did not display cell death due to the lack of expression of the URA3 gene. The creation of the BAPJ69-4A yeast strain provides a high-throughput selection system, called negative chemical complementation, which can be used for both positive and negative selection, providing a fast, powerful tool for discovering novel ligand receptor pairs for applications in drug discovery and protein engineering. Copyright © 2012 Elsevier B.V. All rights reserved.

A replicative plasmid vector allows efficient complementation of pathogenic Leptospira strains.

PubMed

Pappas, Christopher J; Benaroudj, Nadia; Picardeau, Mathieu

2015-05-01

Leptospirosis, an emerging zoonotic disease, remains poorly understood because of a lack of genetic manipulation tools available for pathogenic leptospires. Current genetic manipulation techniques include insertion of DNA by random transposon mutagenesis and homologous recombination via suicide vectors. This study describes the construction of a shuttle vector, pMaORI, that replicates within saprophytic, intermediate, and pathogenic leptospires. The shuttle vector was constructed by the insertion of a 2.9-kb DNA segment including the parA, parB, and rep genes into pMAT, a plasmid that cannot replicate in Leptospira spp. and contains a backbone consisting of an aadA cassette, ori R6K, and oriT RK2/RP4. The inserted DNA segment was isolated from a 52-kb region within Leptospira mayottensis strain 200901116 that is not found in the closely related strain L. mayottensis 200901122. Because of the size of this region and the presence of bacteriophage-like proteins, it is possible that this region is a result of a phage-related genomic island. The stability of the pMaORI plasmid within pathogenic strains was tested by passaging cultures 10 times without selection and confirming the presence of pMaORI. Concordantly, we report the use of trans complementation in the pathogen Leptospira interrogans. Transformation of a pMaORI vector carrying a functional copy of the perR gene in a null mutant background restores the expression of PerR and susceptibility to hydrogen peroxide comparable to that of wild-type cells. In conclusion, we demonstrate the replication of a stable plasmid vector in a large panel of Leptospira strains, including pathogens. The shuttle vector described will expand our ability to perform genetic manipulation of Leptospira spp. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

On-Chip Cellomics: Constructive Understanding of Multicellular Network Using On-Chip Cellomics Technology

NASA Astrophysics Data System (ADS)

Yasuda, Kenji

2012-08-01

We have developed methods and systems of analyzing epigenetic information in cells to expand our understanding of how living systems are determined. Because cells are minimum units reflecting epigenetic information, which is considered to map the history of a parallel-processing recurrent network of biochemical reactions, their behaviors cannot be explained by considering only conventional deonucleotide (DNA) information-processing events. The role of epigenetic information on cells, which complements their genetic information, was inferred by comparing predictions from genetic information with cell behaviour observed under conditions chosen to reveal adaptation processes and community effects. A system of analyzing epigenetic information, on-chip cellomics technology, has been developed starting from the twin complementary viewpoints of cell regulation as an “algebraic” system (emphasis on temporal aspects) and as a “geometric” system (emphasis on spatial aspects) exploiting microfabrication technology and a reconstructive approach of cellular systems not only for single cell-based subjects such as Escherichia coli and macrophages but also for cellular networks like the community effect of cardiomyocytes and plasticity in neuronal networks. One of the most important contributions of this study was to be able to reconstruct the concept of a cell regulatory network from the “local” (molecules expressed at certain times and places) to the “global” (the cell as a viable, functioning system). Knowledge of epigenetic information, which we can control and change during cell lives, complements the genetic variety, and these two types of information are indispensable for living organisms. This new knowlege has the potential to be the basis of cell-based biological and medical fields such as those involving cell-based drug screening and the regeneration of organs from stem cells.

Staphylococcus aureus innate immune evasion is lineage-specific: a bioinfomatics study.

PubMed

McCarthy, Alex J; Lindsay, Jodi A

2013-10-01

Staphylococcus aureus is a major human pathogen, and is targeted by the host innate immune system. In response, S. aureus genomes encode dozens of secreted proteins that inhibit complement, chemotaxis and neutrophil activation resulting in successful evasion of innate immune responses. These proteins include immune evasion cluster proteins (IEC; Chp, Sak, Scn), staphylococcal superantigen-like proteins (SSLs), phenol soluble modulins (PSMs) and several leukocidins. Biochemical studies have indicated that genetic variants of these proteins can have unique functions. To ascertain the scale of genetic variation in secreted immune evasion proteins, whole genome sequences of 88 S. aureus isolates, representing 25 clonal complex (CC) lineages, in the public domain were analysed across 43 genes encoding 38 secreted innate immune evasion protein complexes. Twenty-three genes were variable, with between 2 and 15 variants, and the variants had lineage-specific distributions. They include genes encoding Eap, Ecb, Efb, Flipr/Flipr-like, Hla, Hld, Hlg, Sbi, Scin-B/C and 13 SSLs. Most of these protein complexes inhibit complement, chemotaxis and neutrophil activation suggesting that isolates from each S. aureus lineage respond to the innate immune system differently. In contrast, protein complexes that lyse neutrophils (LukSF-PVL, LukMF, LukED and PSMs) were highly conserved, but can be carried on mobile genetic elements (MGEs). MGEs also encode proteins with narrow host-specificities arguing that their acquisition has important roles in host/environmental adaptation. In conclusion, this data suggests that each lineage of S. aureus evades host immune responses differently, and that isolates can adapt to new host environments by acquiring MGEs and the immune evasion protein complexes that they encode. Cocktail therapeutics that targets multiple variant proteins may be the most appropriate strategy for controlling S. aureus infections. Copyright © 2013 Elsevier B.V. All rights reserved.

The Scl1 protein of M6-type group A Streptococcus binds the human complement regulatory protein, factor H, and inhibits the alternative pathway of complement.

PubMed

Caswell, Clayton C; Han, Runlin; Hovis, Kelley M; Ciborowski, Pawel; Keene, Douglas R; Marconi, Richard T; Lukomski, Slawomir

2008-02-01

Non-specific activation of the complement system is regulated by the plasma glycoprotein factor H (FH). Bacteria can avoid complement-mediated opsonization and phagocytosis through acquiring FH to the cell surface. Here, we characterize an interaction between the streptococcal collagen-like protein Scl1.6 of M6-type group A Streptococcus (GAS) and FH. Using affinity chromatography with immobilized recombinant Scl1.6 protein, we co-eluted human plasma proteins with molecular weight of 155 kDa, 43 kDa and 38 kDa. Mass spectrometry identified the 155 kDa band as FH and two other bands as isoforms of the FH-related protein-1. The identities of all three bands were confirmed by Western immunoblotting with specific antibodies. Structure-function relation studies determined that the globular domain of the Scl1.6 variant specifically binds FH while fused to collagenous tails of various lengths. This binding is not restricted to Scl1.6 as the phylogenetically linked Scl1.55 variant also binds FH. Functional analyses demonstrated the cofactor activity of the rScl1.6-bound FH for factor I-mediated cleavage of C3b. Finally, purified FH bound to the Scl1.6 protein present in the cell wall material obtained from M6-type GAS. In conclusion, we have identified a functional interaction between Scl1 and plasma FH, which may contribute to GAS evasion of complement-mediated opsonization and phagocytosis.

Differentiation of individual selves facilitates group-level benefits of ultrasociality.

PubMed

Ainsworth, Sarah E; Baumeister, Roy F; Vohs, Kathleen D

2016-01-01

Gowdy & Krall's target article complements our recent theorizing on group behavior. In our comment, we elucidate complementary aspects of the two theories and highlight the importance of differentiation of selves for human groups to reap the benefits of ultrasociality. We propose that achieving optimal group outcomes depends on the differentiation of individual selves.

Genetic diversity and population genetic analysis of Donax vittatus (Mollusca: Bivalvia) and phylogeny of the genus with mitochondrial and nuclear markers

NASA Astrophysics Data System (ADS)

Fernández-Pérez, Jenyfer; Froufe, Elsa; Nantón, Ana; Gaspar, Miguel B.; Méndez, Josefina

2017-10-01

In this study, the genetic diversity of Donax vittatus across the Iberian Peninsula was investigated using four mitochondrial (COI, Cytb, 16S F and M types) and three nuclear (H3, 18S and 28S) genes. These same molecular markers were also sequenced in D. semistriatus and D variegatus to address the phylogenetic relationships of the species of the genus Donax common along the European coasts. Our results showed high haplotype diversity in combination with a low nucleotide diversity and a star-shaped network with a predominant haplotype, indicating a recent population expansion for the examined sampling sites of D. vittatus. Furthermore, analyses of population differentiation performed with COI mitochondrial marker, including global FST estimation and pairwise FST values, indicated the non-existence of significant genetic structure in D. vittatus of Northwest Iberian populations. Because these localities show a high genetic similarity, we suggest that D. vittatus could be a potentially alternative exploitable resource, as complement to the D. trunculus fisheries, whose natural stocks have decreased dramatically in some areas. Furthermore, we present for the first time, evidence of DUI in the clams D. vittatus and D. semistriatus.

Applying a statistical PTB detection procedure to complement the gold standard.

PubMed

Noor, Norliza Mohd; Yunus, Ashari; Bakar, S A R Abu; Hussin, Amran; Rijal, Omar Mohd

2011-04-01

This paper investigates a novel statistical discrimination procedure to detect PTB when the gold standard requirement is taken into consideration. Archived data were used to establish two groups of patients which are the control and test group. The control group was used to develop the statistical discrimination procedure using four vectors of wavelet coefficients as feature vectors for the detection of pulmonary tuberculosis (PTB), lung cancer (LC), and normal lung (NL). This discrimination procedure was investigated using the test group where the number of sputum positive and sputum negative cases that were correctly classified as PTB cases were noted. The proposed statistical discrimination method is able to detect PTB patients and LC with high true positive fraction. The method is also able to detect PTB patients that are sputum negative and therefore may be used as a complement to the gold standard. Copyright © 2010 Elsevier Ltd. All rights reserved.

Methodological approaches in analysing observational data: A practical example on how to address clustering and selection bias.

PubMed

Trutschel, Diana; Palm, Rebecca; Holle, Bernhard; Simon, Michael

2017-11-01

Because not every scientific question on effectiveness can be answered with randomised controlled trials, research methods that minimise bias in observational studies are required. Two major concerns influence the internal validity of effect estimates: selection bias and clustering. Hence, to reduce the bias of the effect estimates, more sophisticated statistical methods are needed. To introduce statistical approaches such as propensity score matching and mixed models into representative real-world analysis and to conduct the implementation in statistical software R to reproduce the results. Additionally, the implementation in R is presented to allow the results to be reproduced. We perform a two-level analytic strategy to address the problems of bias and clustering: (i) generalised models with different abilities to adjust for dependencies are used to analyse binary data and (ii) the genetic matching and covariate adjustment methods are used to adjust for selection bias. Hence, we analyse the data from two population samples, the sample produced by the matching method and the full sample. The different analysis methods in this article present different results but still point in the same direction. In our example, the estimate of the probability of receiving a case conference is higher in the treatment group than in the control group. Both strategies, genetic matching and covariate adjustment, have their limitations but complement each other to provide the whole picture. The statistical approaches were feasible for reducing bias but were nevertheless limited by the sample used. For each study and obtained sample, the pros and cons of the different methods have to be weighted. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Elevated Urinary Levels of 8-Hydroxy-2'-deoxyguanosine in a Japanese Child of Xeroderma Pigmentosum/Cockayne Syndrome Complex with Infantile Onset of Nephrotic Syndrome.

PubMed

Kondo, Daiki; Noguchi, Atsuko; Tamura, Hiroaki; Tsuchida, Satoko; Takahashi, Ikuko; Kubota, Hiroki; Yano, Tamami; Oyama, Chikako; Sawaishi, Yukio; Moriwaki, Shinichi; Takahashi, Tsutomu

2016-07-01

Nucleotide excision repair (NER) is an essential biological pathway protecting against ultraviolet light-induced DNA damage. Deficient NER causes a group of rare genetic disorders including two autosomal recessive diseases, xeroderma pigmentosum (XP) and Cockayne syndrome (CS). In addition to the cutaneous photosensitivity shared in XP and CS, CS is featured by growth failure, neurological deterioration, microcephaly, and deep sunken eyes. XP/CS complex is an extremely rare type of NER disorder with a distinct phenotype that is characterized by the skin and eye pathology of XP and the somatic and neurological abnormalities of CS. Some of CS cases have been reported to be complicated with renal failure, but the genetic background or the etiology of the renal failure has not been reported. We herein report a 1-year-old Japanese boy with XP/CS complex, complicated by nephrotic syndrome. Diagnosis was confirmed by the presence of compound heterozygous mutations, G47R (c.139G>A) and R616G (c.1846C>G), in the excision repair cross-complementation group 2 (ERCC2) gene. The kidney biopsies, performed at the age of 1 year and 2 months, revealed diffuse expansion of the mesangial matrix and segmental glomerulosclerosis under light microscopy, and diffused thin capillary walls with partially lamellated regions under electron microscopy. Notably, high levels of urinary 8-hydroxy-2'-deoxyguanosin, known as an oxidative stress marker, were observed during the clinical course. The patient died at the age of 1 year and 11 months because of renal failure. We suggest the involvement of oxidative stress in the pathogenesis of nephrotic syndrome in NER disorders.

Impact of DNA repair genes polymorphism (XPD and XRCC1) on the risk of breast cancer in Egyptian female patients.

PubMed

Hussien, Yousry Mostafa; Gharib, Amal F; Awad, Hanan A; Karam, Rehab A; Elsawy, Wael H

2012-02-01

The genes involved in DNA repair system play a crucial role in the protection against mutations. It has been hypothesized that functional deficiencies in highly conserved DNA repair processes resulting from polymorphic variation may increase genetic susceptibility to breast cancer (BC). The aim of the present study was to evaluate the association of genetic polymorphisms in 2 DNA repair genes, XPD (Asp312Asn) and XRCC1 (A399G), with BC susceptibility. We further investigated the potential combined effect of these DNA repair variants on BC risk. Both XPD (xeroderma pigmentosum group D) and XRCC1 (X-ray repair cross-complementing group 1) polymorphisms were characterized in 100 BC Egyptian females and 100 healthy women who had no history of any malignancy by amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) method and PCR with confronting two-pair primers (PCR-CTPP), using DNA from peripheral blood in a case control study. Our results revealed that the frequencies of AA genotype of XPD codon 312 polymorphism were significantly higher in the BC patients than in the normal individuals (P ≤ 0.003), and did not observe any association between the XRCC1 Arg399Gln polymorphism and risk of developing BC. Also, no association between both XPD Asp312Asn and XRCC1 A399G polymorphisms and the clinical characteristics of disease. Finally, the combination of AA(XPD) + AG(XRCC1) were significantly associated with BC risk. Our results suggested that, XPD gene is an important candidate gene for susceptibility to BC. Also, gene-gene interaction between XPD(AA) + XRCC1(AG) polymorphism may be associated with increased risk of BC in Egyptian women.

Biological safety concepts of genetically modified live bacterial vaccines.

PubMed

Frey, Joachim

2007-07-26

Live vaccines possess the advantage of having access to induce cell-mediated and antibody-mediated immunity; thus in certain cases they are able to prevent infection, and not only disease. Furthermore, live vaccines, particularly bacterial live vaccines, are relatively cheap to produce and easy to apply. Hence they are suitable to immunize large communities or herds. The induction of both cell-mediated immunity as well as antibody-mediated immunity, which is particularly beneficial in inducing mucosal immune responses, is obtained by the vaccine-strain's ability to colonize and multiply in the host without causing disease. For this reason, live vaccines require attenuation of virulence of the bacterium to which immunity must be induced. Traditionally attenuation was achieved simply by multiple passages of the microorganism on growth medium, in animals, eggs or cell cultures or by chemical or physical mutagenesis, which resulted in random mutations that lead to attenuation. In contrast, novel molecular methods enable the development of genetically modified organisms (GMOs) targeted to specific genes that are particularly suited to induce attenuation or to reduce undesirable effects in the tissue in which the vaccine strains can multiply and survive. Since live vaccine strains (attenuated by natural selection or genetic engineering) are potentially released into the environment by the vaccinees, safety issues concerning the medical as well as environmental aspects must be considered. These involve (i) changes in cell, tissue and host tropism, (ii) virulence of the carrier through the incorporation of foreign genes, (iii) reversion to virulence by acquisition of complementation genes, (iv) exchange of genetic information with other vaccine or wild-type strains of the carrier organism and (v) spread of undesired genes such as antibiotic resistance genes. Before live vaccines are applied, the safety issues must be thoroughly evaluated case-by-case. Safety assessment includes knowledge of the precise function and genetic location of the genes to be mutated, their genetic stability, potential reversion mechanisms, possible recombination events with dormant genes, gene transfer to other organisms as well as gene acquisition from other organisms by phage transduction, transposition or plasmid transfer and cis- or trans-complementation. For this, GMOs that are constructed with modern techniques of genetic engineering display a significant advantage over random mutagenesis derived live organisms. The selection of suitable GMO candidate strains can be made under in vitro conditions using basic knowledge on molecular mechanisms of pathogenicity of the corresponding bacterial species rather than by in vivo testing of large numbers of random mutants. This leads to a more targeted safety testing on volunteers and to a reduction in the use of animal experimentation.

Microsatellite analysis of genetic divergence among populations of giant Galápagos tortoises.

PubMed

Ciofi, Claudio; Milinkovitch, Michel C; Gibbs, James P; Caccone, Adalgisa; Powell, Jeffrey R

2002-11-01

Giant Galápagos tortoises represent an interesting model for the study of patterns of genetic divergence and adaptive differentiation related to island colonization events. Recent mitochondrial DNA work elucidated the evolutionary history of the species and helped to clarify aspects of nomenclature. We used 10 microsatellite loci to assess levels of genetic divergence among and within island populations. In particular, we described the genetic structure of tortoises on the island of Isabela, where discrimination of different taxa is still subject of debate. Individual island populations were all genetically distinct. The island of Santa Cruz harboured two distinct populations. On Isabela, populations of Volcan Wolf, Darwin and Alcedo were significantly different from each other. On the other hand, Volcan Wolf showed allelic similarity with the island of Santiago. On Southern Isabela, lower genetic divergence was found between Northeast Sierra Negra and Volcan Alcedo, while patterns of gene flow were recorded among tortoises of Cerro Azul and Southeast Sierra Negra. These tortoises have endured heavy exploitation during the last three centuries and recently attracted much concern due to the current number of stochastic and deterministic threats to extant populations. Our study complements previous investigation based on mtDNA diversity and provides further information that may help devising tortoise management plans.

Accelerating Genetic Gains in Legumes for the Development of Prosperous Smallholder Agriculture: Integrating Genomics, Phenotyping, Systems Modelling and Agronomy.

PubMed

Varshney, Rajeev K; Thudi, Mahendar; Pandey, Manish K; Tardieu, Francois; Ojiewo, Chris; Vadez, Vincent; Whitbread, Anthony M; Siddique, Kadambot H M; Nguyen, Henry T; Carberry, Peter S; Bergvinson, David

2018-03-05

Grain legumes form an important component of the human diet, feed for livestock and replenish soil fertility through biological nitrogen fixation. Globally, the demand for food legumes is increasing as they complement cereals in protein requirements and possess a high percentage of digestible protein. Climate change has enhanced the frequency and intensity of drought stress that is posing serious production constraints, especially in rainfed regions where most legumes are produced. Genetic improvement of legumes, like other crops, is mostly based on pedigree and performance-based selection over the last half century. For achieving faster genetic gains in legumes in rainfed conditions, this review article proposes the integration of modern genomics approaches, high throughput phenomics and simulation modelling as support for crop improvement that leads to improved varieties that perform with appropriate agronomy. Selection intensity, generation interval and improved operational efficiencies in breeding are expected to further enhance the genetic gain in experiment plots. Improved seed access to farmers, combined with appropriate agronomic packages in farmers' fields, will deliver higher genetic gains. Enhanced genetic gains including not only productivity but also nutritional and market traits will increase the profitability of farmers and the availability of affordable nutritious food especially in developing countries.

Classification of Blood-Group Antibodies as β2M or γ Globulin

PubMed Central

Adinolfi, M.; Polley, Margaret J.; Hunter, Denise A.; Mollison, P. L.

1962-01-01

Thirty selected blood-group antibodies (excluding anti-A and anti-B) have been classified as β2M (19S γ) globulin, γ (7S γ) globulin or mixtures, using the following three methods: fractionation on a DEAE-cellulose column; indirect anti-globulin tests, using specific anti-β2M-globulin and anti-γ-globulin sera; and treatment with 2-mercapto-ethanol. With only minor exceptions, results obtained with the three methods were in agreement. Most blood-group antibodies within the Le, MNSs and P systems appear to be `naturally occurring' and these were found to be β2M globulin. Blood-group antibodies within the Rh, K and Jk systems, which had arisen after an antigenic stimulus, were usually γ globulin but were occasionally β2M globulin. Antibodies composed of β2M globulin usually behave as agglutinins but may behave as incomplete antibodies (e.g. some examples of anti-Jka); conversely, antibodies composed of γ globulin usually behave as incomplete antibodies but may behave as agglutinins (e.g. an example of anti-M). The ability to bind complement seems to be related more to the blood-group specificity of the particular antibody than to its molecular size. For example, anti-Jka, when composed either of γ or β2M globulin, seems invariably to bind complement, whereas potent anti-M or anti-Rh, whether composed of γ or β2M globulin, do not bind complement. PMID:14011076

Genetic Code Expansion as a Tool to Study Regulatory Processes of Transcription

NASA Astrophysics Data System (ADS)

Schmidt, Moritz; Summerer, Daniel

2014-02-01

The expansion of the genetic code with noncanonical amino acids (ncAA) enables the chemical and biophysical properties of proteins to be tailored, inside cells, with a previously unattainable level of precision. A wide range of ncAA with functions not found in canonical amino acids have been genetically encoded in recent years and have delivered insights into biological processes that would be difficult to access with traditional approaches of molecular biology. A major field for the development and application of novel ncAA-functions has been transcription and its regulation. This is particularly attractive, since advanced DNA sequencing- and proteomics-techniques continue to deliver vast information on these processes on a global level, but complementing methodologies to study them on a detailed, molecular level and in living cells have been comparably scarce. In a growing number of studies, genetic code expansion has now been applied to precisely control the chemical properties of transcription factors, RNA polymerases and histones, and this has enabled new insights into their interactions, conformational changes, cellular localizations and the functional roles of posttranslational modifications.

Versatile Genetic Tool Box for the Crenarchaeote Sulfolobus acidocaldarius

PubMed Central

Wagner, Michaela; van Wolferen, Marleen; Wagner, Alexander; Lassak, Kerstin; Meyer, Benjamin H.; Reimann, Julia; Albers, Sonja-Verena

2012-01-01

For reverse genetic approaches inactivation or selective modification of genes are required to elucidate their putative function. Sulfolobus acidocaldarius is a thermoacidophilic Crenarchaeon which grows optimally at 76°C and pH 3. As many antibiotics do not withstand these conditions the development of a genetic system in this organism is dependent on auxotrophies. Therefore we constructed a pyrE deletion mutant of S. acidocaldarius wild type strain DSM639 missing 322 bp called MW001. Using this strain as the starting point, we describe here different methods using single as well as double crossover events to obtain markerless deletion mutants, tag genes genomically and ectopically integrate foreign DNA into MW001. These methods enable us to construct single, double, and triple deletions strains that can still be complemented with the pRN1 based expression vector. Taken together we have developed a versatile and robust genetic tool box for the crenarchaeote S. acidocaldarius that will promote the study of unknown gene functions in this organism and makes it a suitable host for synthetic biology approaches. PMID:22707949

Reverse genetics of measles virus and resulting multivalent recombinant vaccines: applications of recombinant measles viruses.

PubMed

Billeter, M A; Naim, H Y; Udem, S A

2009-01-01

An overview is given on the development of technologies to allow reverse genetics of RNA viruses, i.e., the rescue of viruses from cDNA, with emphasis on nonsegmented negative-strand RNA viruses (Mononegavirales), as exemplified for measles virus (MV). Primarily, these technologies allowed site-directed mutagenesis, enabling important insights into a variety of aspects of the biology of these viruses. Concomitantly, foreign coding sequences were inserted to (a) allow localization of virus replication in vivo through marker gene expression, (b) develop candidate multivalent vaccines against measles and other pathogens, and (c) create candidate oncolytic viruses. The vector use of these viruses was experimentally encouraged by the pronounced genetic stability of the recombinants unexpected for RNA viruses, and by the high load of insertable genetic material, in excess of 6 kb. The known assets, such as the small genome size of the vector in comparison to DNA viruses proposed as vectors, the extensive clinical experience of attenuated MV as vaccine with a proven record of high safety and efficacy, and the low production cost per vaccination dose are thus favorably complemented.

Symposium on Oxygen Binding Heme Proteins Structure, Dynamics, Function and Genetics Held in Pacific Grove, California on 9-13 October 1988

DTIC Science & Technology

1989-08-15

hemoglobin, hemoglobin that has been internally crosslinked, polymerized crosslinked-hemoglobin, and I hemoglobin that is conjugated to carriers such as...dextran and polyethyleneglycol are also under intense study. To date, only unmodified hemoglobin and crosslinked- polymerized hemoglobin have been...complement and may bind bacterial endotoxins in vivo . I During the past 3 years, the US Army has supported the industrial scaleup of one such product

Generation and Characterization of Acid Tolerant Fibrobacter succinogenes S85

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Chia-wei; Spike, Thomas; Klingeman, Dawn M.

Microorganisms are key components for plant biomass breakdown within rumen environments. Fibrobacter succinogenes have been identified as being active and dominant cellulolytic members of the rumen. In this study, F. succinogenes type strain S85 was adapted for steady state growth in continuous culture at pH 5.75 and confirmed to grow in the range of pH 5.60–5.65, which is lower than has been reported previously. Wild type and acid tolerant strains digested corn stover with equal efficiency in batch culture at low pH. RNA-seq analysis revealed 268 and 829 genes were differentially expressed at pH 6.10 and 5.65 compared to pHmore » 6.70, respectively. Resequencing analysis identified seven single nucleotide polymorphisms (SNPs) in the sufD, yidE, xylE, rlmM, mscL and dosC genes of acid tolerant strains. Due to the absence of a F. succinogenes genetic system, homologues in Escherichia coli were mutated and complemented and the resulting strains were assayed for acid survival. Complementation with wild-type or acid tolerant F. succinogenes sufD restored E. coli wild-type levels of acid tolerance, suggesting a possible role in acid homeostasis. Here, recent genetic engineering developments need to be adapted and applied in F. succinogenes to further our understanding of this bacterium.« less

Generation and Characterization of Acid Tolerant Fibrobacter succinogenes S85

DOE PAGES

Wu, Chia-wei; Spike, Thomas; Klingeman, Dawn M.; ...

2017-05-23

Microorganisms are key components for plant biomass breakdown within rumen environments. Fibrobacter succinogenes have been identified as being active and dominant cellulolytic members of the rumen. In this study, F. succinogenes type strain S85 was adapted for steady state growth in continuous culture at pH 5.75 and confirmed to grow in the range of pH 5.60–5.65, which is lower than has been reported previously. Wild type and acid tolerant strains digested corn stover with equal efficiency in batch culture at low pH. RNA-seq analysis revealed 268 and 829 genes were differentially expressed at pH 6.10 and 5.65 compared to pHmore » 6.70, respectively. Resequencing analysis identified seven single nucleotide polymorphisms (SNPs) in the sufD, yidE, xylE, rlmM, mscL and dosC genes of acid tolerant strains. Due to the absence of a F. succinogenes genetic system, homologues in Escherichia coli were mutated and complemented and the resulting strains were assayed for acid survival. Complementation with wild-type or acid tolerant F. succinogenes sufD restored E. coli wild-type levels of acid tolerance, suggesting a possible role in acid homeostasis. Here, recent genetic engineering developments need to be adapted and applied in F. succinogenes to further our understanding of this bacterium.« less

Plasmid Vectors for Xylella fastidiosa Utilizing a Toxin-Antitoxin System for Stability in the Absence of Antibiotic Selection.

PubMed

Burbank, Lindsey P; Stenger, Drake C

2016-08-01

The phytopathogen Xylella fastidiosa causes disease in a variety of important crop and landscape plants. Functional genetic studies have led to a broader understanding of virulence mechanisms used by this pathogen in the grapevine host. Plasmid shuttle vectors are important tools in studies of bacterial genetics but there are only a limited number of plasmid vectors available that replicate in X. fastidiosa, and even fewer that are retained without antibiotic selection. Two plasmids are described here that show stable replication in X. fastidiosa and are effective for gene complementation both in vitro and in planta. Plasmid maintenance is facilitated by incorporation of the PemI/PemK plasmid addiction system, consisting of PemK, an endoribonuclease toxin, and its cognate antitoxin, PemI. Vector pXf20pemIK utilizes a native X. fastidiosa replication origin as well as a high-copy-number pUC origin for propagation in Escherichia coli cloning strains. Broad-host-range vector pBBR5pemIK is a medium- to low-copy-number plasmid based on the pBBR1 backbone. Both plasmids are maintained for extended periods of time in the absence of antibiotic selection, as well as up to 14 weeks in grapevine, without affecting bacterial fitness. These plasmids present an alternative to traditional complementation and expression vectors which rely on antibiotic selection for plasmid retention.

A Drosophila SNAP-25 null mutant reveals context-dependent redundancy with SNAP-24 in neurotransmission.

PubMed Central

Vilinsky, Ilya; Stewart, Bryan A; Drummond, James; Robinson, Iain; Deitcher, David L

2002-01-01

The synaptic protein SNAP-25 is an important component of the neurotransmitter release machinery, although its precise function is still unknown. Genetic analysis of other synaptic proteins has yielded valuable information on their role in synaptic transmission. In this study, we performed a mutagenesis screen to identify new SNAP-25 alleles that fail to complement our previously isolated recessive temperature-sensitive allele of SNAP-25, SNAP-25(ts). In a screen of 100,000 flies, 26 F(1) progeny failed to complement SNAP-25(ts) and 21 of these were found to be null alleles of SNAP-25. These null alleles die at the pharate adult stage and electroretinogram recordings of these animals reveal that synaptic transmission is blocked. At the third instar larval stage, SNAP-25 nulls exhibit nearly normal neurotransmitter release at the neuromuscular junction. This is surprising since SNAP-25(ts) larvae exhibit a much stronger synaptic phenotype. Our evidence indicates that a related protein, SNAP-24, can substitute for SNAP-25 at the larval stage in SNAP-25 nulls. However, if a wild-type or mutant form of SNAP-25 is present, then SNAP-24 does not appear to take part in neurotransmitter release at the larval NMJ. These results suggest that the apparent redundancy between SNAP-25 and SNAP-24 is due to inappropriate genetic substitution. PMID:12242238

Quantitative and Dynamic Imaging of ATM Kinase Activity by Bioluminescence Imaging.

PubMed

Nyati, Shyam; Young, Grant; Ross, Brian Dale; Rehemtulla, Alnawaz

2017-01-01

Ataxia telangiectasia mutated (ATM) is a serine/threonine kinase critical to the cellular DNA damage response, including DNA double strand breaks (DSBs). ATM activation results in the initiation of a complex cascade of events facilitating DNA damage repair, cell cycle checkpoint control, and survival. Traditionally, protein kinases have been analyzed in vitro using biochemical methods (kinase assays using purified proteins or immunological assays) requiring a large number of cells and cell lysis. Genetically encoded biosensors based on optical molecular imaging such as fluorescence or bioluminescence have been developed to enable interrogation of kinase activities in live cells with a high signal to background. We have genetically engineered a hybrid protein whose bioluminescent activity is dependent on the ATM-mediated phosphorylation of a substrate. The engineered protein consists of the split luciferase-based protein complementation pair with a CHK2 (a substrate for ATM kinase activity) target sequence and a phospho-serine/threonine-binding domain, FHA2, derived from yeast Rad53. Phosphorylation of the serine residue within the target sequence by ATM would lead to its interaction with the phospho-serine-binding domain, thereby preventing complementation of the split luciferase pair and loss of reporter activity. Bioluminescence imaging of reporter-expressing cells in cultured plates or as mouse xenografts provides a quantitative surrogate for ATM kinase activity and therefore the cellular DNA damage response in a noninvasive, dynamic fashion.

Quantitative and Dynamic Imaging of ATM Kinase Activity.

PubMed

Nyati, Shyam; Young, Grant; Ross, Brian Dale; Rehemtulla, Alnawaz

2017-01-01

Ataxia telangiectasia mutated (ATM) is a serine/threonine kinase critical to the cellular DNA-damage response, including DNA double-strand breaks (DSBs). ATM activation results in the initiation of a complex cascade of events facilitating DNA damage repair, cell cycle checkpoint control, and survival. Traditionally, protein kinases have been analyzed in vitro using biochemical methods (kinase assays using purified proteins or immunological assays) requiring a large number of cells and cell lysis. Genetically encoded biosensors based on optical molecular imaging such as fluorescence or bioluminescence have been developed to enable interrogation of kinase activities in live cells with a high signal to background. We have genetically engineered a hybrid protein whose bioluminescent activity is dependent on the ATM-mediated phosphorylation of a substrate. The engineered protein consists of the split luciferase-based protein complementation pair with a CHK2 (a substrate for ATM kinase activity) target sequence and a phospho-serine/threonine-binding domain, FHA2, derived from yeast Rad53. Phosphorylation of the serine residue within the target sequence by ATM would lead to its interaction with the phospho-serine-binding domain, thereby preventing complementation of the split luciferase pair and loss of reporter activity. Bioluminescence imaging of reporter expressing cells in cultured plates or as mouse xenografts provides a quantitative surrogate for ATM kinase activity and therefore the cellular DNA damage response in a noninvasive, dynamic fashion.

Preparation of Low Molecular Weight Chondroitin Sulfates, Screening of a High Anti-Complement Capacity of Low Molecular Weight Chondroitin Sulfate and Its Biological Activity Studies in Attenuating Osteoarthritis.

PubMed

Li, Lian; Li, Yan; Feng, Danyang; Xu, Linghua; Yin, Fengxin; Zang, Hengchang; Liu, Chunhui; Wang, Fengshan

2016-10-11

Chondroitin sulfate (CS) plays important roles in the complement system. However, the CS structure is complicated due to different sources and the number and positions of sulfate groups. The objective of this study was to prepare different low molecular weight chondroitin sulfates (LMWCSs) and to investigate the biological activity in anti-complement capacity. A series of LMWCSs was prepared from different sources and characterized by ultraviolet-visible (UV) spectroscopy, high-performance liquid chromatography (HPLC), size exclusion chromatography-multiangle laser light scattering (SEC-MALLS) and nuclear magnetic resonance (NMR) spectroscopy. Hemolytic, anti-complement 3 deposition capacity and cell viability assays were carried out to investigate the biological activities in vitro. The results showed that LMWCS prepared from shark cartilage with the oxidative degradation method (LMWCS-S-O) had the best anti-complement capacity. LMWCS-S-O could inhibit the alternative pathway of the complement system and protect chondrocytes from cell death. The attenuating effect of LMWCS-S-O on Osteoarthritis (OA) was investigated by destabilization of the medial meniscus (DMM) model in vivo. Functional wind-up, histological and C5b-9 analyses were used to evaluate the treatment effect on the OA model. In vivo results showed that LMWCS-S-O could attenuate OA. LMWCS-S-O with a high content of ΔDi-2,6diS and ΔDi-6S could be used for attenuating OA through regulating the complement system.

Preclinical development of BCG.HIVA2auxo.int, harboring an integrative expression vector, for a HIV-TB Pediatric vaccine. Enhancement of stability and specific HIV-1 T-cell immunity.

PubMed

Mahant, Aakash; Saubi, Narcís; Eto, Yoshiki; Guitart, Núria; Gatell, Josep Ma; Hanke, Tomáš; Joseph, Joan

2017-08-03

One of the critical issues that should be addressed in the development of a BCG-based HIV vaccine is genetic plasmid stability. Therefore, to address this issue we have considered using integrative vectors and the auxotrophic mutant of BCG complemented with a plasmid carrying a wild-type complementing gene. In this study, we have constructed an integrative E. coli-mycobacterial shuttle plasmid, p2auxo.HIVA int , expressing the HIV-1 clade A immunogen HIVA. This shuttle vector uses an antibiotic resistance-free mechanism for plasmid selection and maintenance. It was first transformed into a glycine auxotrophic E. coli strain and subsequently transformed into a lysine auxotrophic Mycobacterium bovis BCG strain to generate the vaccine BCG.HIVA 2auxo.int . Presence of the HIVA gene sequence and protein expression was confirmed. We demonstrated that the in vitro stability of the integrative plasmid p2auxo.HIVA int was increased 4-fold, as compared with the BCG strain harboring the episomal plasmid, and was genetically and phenotypically characterized. The BCG.HIVA 2auxo.int vaccine in combination with modified vaccinia virus Ankara (MVA).HIVA was found to be safe and induced HIV-1 and Mycobacterium tuberculosis-specific interferon-γ-producing T-cell responses in adult BALB/c mice. We have engineered a more stable and immunogenic BCG-vectored vaccine using the prototype immunogen HIVA. Thus, the use of integrative expression vectors and the antibiotic-free plasmid selection system based on "double" auxotrophic complementation are likely to improve the mycobacterial vaccine stability in vivo and immunogenicity to develop not only recombinant BCG-based vaccines expressing second generation of HIV-1 immunogens but also other major pediatric pathogens to prime protective responses shortly following birth.

Age-related macular degeneration—emerging pathogenetic and therapeutic concepts

PubMed Central

GEHRS, KAREN M.; ANDERSON, DON H.; JOHNSON, LINCOLN V.; HAGEMAN, GREGORY S.

2014-01-01

Today, the average life expectancy in developed nations is over 80 years and climbing. And yet, the quality of life during those additional years is often significantly diminished by the effects of age-related, degenerative diseases, including age-related macular degeneration (AMD), the leading cause of blindness in the elderly worldwide. AMD is characterized by a progressive loss of central vision attributable to degenerative and neovascular changes in the macula, a highly specialized region of the ocular retina responsible for fine visual acuity. Estimates gathered from the most recent World Health Organization (WHO) global eye disease survey conservatively indicate that 14 million persons are blind or severely visually impaired because of AMD. The disease has a tremendous impact on the physical and mental health of the geriatric population and their families and is becoming a major public health burden. Currently, there is neither a cure nor a means to prevent AMD. Palliative treatment options for the less prevalent, late-stage ‘wet’ form of the disease include anti-neovascular agents, photodynamic therapy and thermal laser. There are no current therapies for the more common ‘dry’ AMD, except for the use of antioxidants that delay progression in 20%–25% of eyes. New discoveries, however, are beginning to provide a much clearer picture of the relevant cellular events, genetic factors, and biochemical processes associated with early AMD. Recently, compelling evidence has emerged that the innate immune system and, more specifically, uncontrolled regulation of the complement alternative pathway plays a central role in the pathobiology of AMD. The complement Factor H gene—which encodes the major inhibitor of the complement alternative pathway—is the first gene identified in multiple independent studies that confers a significant genetic risk for the development of AMD. The emergence of this new paradigm of AMD pathogenesis should hasten the development of novel diagnostic and therapeutic approaches for this disease that will dramatically improve the quality of our prolonged lifespan. PMID:17101537

Psychological therapies for sickle cell disease and pain.

PubMed

Anie, K A; Green, J

2002-01-01

Sickle cell disease comprises a group of genetic blood disorders, and occurs when the sickle haemoglobin gene is inherited from both parents. The effects of the condition are: varying degrees of anaemia which if severe reduce the capacity for mobility; predisposition to obstruction of small blood capillaries causing pain in muscle and bone known as "crises"; damage to major organs such as the spleen, liver, kidneys, and lungs; and increased vulnerability to severe infections. There are both medical and non-medical complications, and treatment is usually symptomatic and palliative in nature. Psychological intervention for individuals with sickle cell disease seems viable in complementing current medical treatment, and studies examining their efficacy appear to have also yielded encouraging results. To examine the evidence that in patients with sickle cell disease, psychological treatment improves the ability to cope with the condition. The Cochrane Cystic Fibrosis and Genetic Disorders Group specialist trials register which comprises references from comprehensive electronic database searches. Also, hand searching relevant journals, hand searching abstract books of conference proceedings, and searches on the Internet were performed. Date of the most recent search of the Group's specialised register: January 2001. All randomised or quasi-randomised controlled trials comparing the use of psychological intervention to no (psychological) intervention in patients with sickle cell disease. Both reviewers independently extracted data and assessed trial quality. Five studies were identified in the initial search, of which three studies, with a total of 158 patients were eligible for inclusion in the review. Published data reveal that family education and cognitive behavioural therapy can help patients cope with sickle cell disease. Patient education programmes improve knowledge and attitudes of patients with sickle cell disease. There is as yet however, insufficient evidence to demonstrate the role of other psychological therapies. This systematic review has clearly identified the need for well-designed, adequately powered, multicentre randomised controlled trials assessing the effectiveness of specific intervention in sickle cell disease.

EST-derived SSR markers used as anchor loci for the construction of a consensus linkage map in ryegrass (Lolium spp.)

PubMed Central

2010-01-01

Background Genetic markers and linkage mapping are basic prerequisites for marker-assisted selection and map-based cloning. In the case of the key grassland species Lolium spp., numerous mapping populations have been developed and characterised for various traits. Although some genetic linkage maps of these populations have been aligned with each other using publicly available DNA markers, the number of common markers among genetic maps is still low, limiting the ability to compare candidate gene and QTL locations across germplasm. Results A set of 204 expressed sequence tag (EST)-derived simple sequence repeat (SSR) markers has been assigned to map positions using eight different ryegrass mapping populations. Marker properties of a subset of 64 EST-SSRs were assessed in six to eight individuals of each mapping population and revealed 83% of the markers to be polymorphic in at least one population and an average number of alleles of 4.88. EST-SSR markers polymorphic in multiple populations served as anchor markers and allowed the construction of the first comprehensive consensus map for ryegrass. The integrated map was complemented with 97 SSRs from previously published linkage maps and finally contained 284 EST-derived and genomic SSR markers. The total map length was 742 centiMorgan (cM), ranging for individual chromosomes from 70 cM of linkage group (LG) 6 to 171 cM of LG 2. Conclusions The consensus linkage map for ryegrass based on eight mapping populations and constructed using a large set of publicly available Lolium EST-SSRs mapped for the first time together with previously mapped SSR markers will allow for consolidating existing mapping and QTL information in ryegrass. Map and markers presented here will prove to be an asset in the development for both molecular breeding of ryegrass as well as comparative genetics and genomics within grass species. PMID:20712870

Multigene assessment of the species boundaries and sexual status of the basidiomycetous yeasts Cryptococcus flavescens and C. terrestris (Tremellales).

PubMed

Yurkov, Andrey; Guerreiro, Marco A; Sharma, Lav; Carvalho, Cláudia; Fonseca, Álvaro

2015-01-01

Cryptococcus flavescens and C. terrestris are phenotypically indistinguishable sister species that belong to the order Tremellales (Tremellomycetes, Basidiomycota) and which may be mistaken for C. laurentii based on phenotype. Phylogenetic separation between C. flavescens and C. terrestris was based on rDNA sequence analyses, but very little is known on their intraspecific genetic variability or propensity for sexual reproduction. We studied 59 strains from different substrates and geographic locations, and used a multilocus sequencing (MLS) approach complemented with the sequencing of mating type (MAT) genes to assess genetic variation and reexamine the boundaries of the two species, as well as their sexual status. The following five loci were chosen for MLS: the rDNA ITS-LSU region, the rDNA IGS1 spacer, and fragments of the genes encoding the largest subunit of RNA polymerase II (RPB1), the translation elongation factor 1 alpha (TEF1) and the p21-activated protein kinase (STE20). Phylogenetic network analyses confirmed the genetic separation of the two species and revealed two additional cryptic species, for which the names Cryptococcus baii and C. ruineniae are proposed. Further analyses of the data revealed a high degree of genetic heterogeneity within C. flavescens as well as evidence for recombination between lineages detected for this species. Strains of C. terrestris displayed higher levels of similarity in all analysed genes and appear to make up a single recombining group. The two MAT genes (STE3 and SXI1/SXI2) sequenced for C. flavescens strains confirmed the potential for sexual reproduction and suggest the presence of a tetrapolar mating system with a biallelic pheromone/receptor locus and a multiallelic HD locus. In C. terrestris we could only sequence STE3, which revealed a biallelic P/R locus. In spite of the strong evidence for sexual recombination in the two species, attempts at mating compatible strains of both species on culture media were unsuccessful.

Patient-reported disease knowledge and educational needs in Lynch syndrome: findings of an interactive multidisciplinary patient conference

PubMed Central

2014-01-01

Background Patients with Lynch Syndrome, the most common hereditary colorectal cancer syndrome, benefit from genetic education and family counseling regarding diagnostic testing and cancer surveillance/prevention recommendations. Although genetic counseling is currently the most common venue where such education and counseling takes place, little is known about the level of disease knowledge and education needs as directly reported by patients and families with Lynch Syndrome. Furthermore, experiences with forums for larger-scale knowledge transfer have been limited in the current literature. Methods We conducted a one-day interactive multidisciplinary patient conference, designed to complement individual genetic counseling for updating disease knowledge, supportive networking and needs assessment among Lynch Syndrome patients and their family members. The patient conference was designed utilizing the conceptual framework of action research. Paired pre- and post-conference surveys were administered to 44 conference participants anonymously to assess patient-reported disease knowledge and education needs. Results A multidisciplinary team of expert providers utilized a variety of educational formats during the one-day conference. Four main focus areas were: genetic testing, surveillance/prevention, living with Lynch Syndrome, and update on research. Thirty-two participants (73%) completed the pre-conference, and 28 (64%) participants completed the post-conference surveys. Nineteen respondents were affected and the remaining were unaffected. The scores of the disease-knowledge items significantly increased from 84% pre- to 92% post-conference (p = 0.012). Patients reported a high level of satisfaction and identified further knowledge needs in nutrition (71%), surveillance/prevention options (71%), support groups (36%), cancer risk assessment (32%), active role in medical care (32%), and research opportunities (5%). Conclusion Our experience with a dedicated patient education conference focused on Lynch Syndrome demonstrated that such an educational format is effective for updating or reinforcing disease knowledge, for identifying patient-reported unmet educational needs, as well as for peer-support. PMID:24499499

Patient-reported disease knowledge and educational needs in Lynch syndrome: findings of an interactive multidisciplinary patient conference.

PubMed

Bannon, Sarah A; Mork, Maureen; Vilar, Eduardo; Peterson, Susan K; Lu, Karen; Lynch, Patrick M; Rodriguez-Bigas, Miguel A; You, Yiqian Nancy

2014-02-05

Patients with Lynch Syndrome, the most common hereditary colorectal cancer syndrome, benefit from genetic education and family counseling regarding diagnostic testing and cancer surveillance/prevention recommendations. Although genetic counseling is currently the most common venue where such education and counseling takes place, little is known about the level of disease knowledge and education needs as directly reported by patients and families with Lynch Syndrome. Furthermore, experiences with forums for larger-scale knowledge transfer have been limited in the current literature. We conducted a one-day interactive multidisciplinary patient conference, designed to complement individual genetic counseling for updating disease knowledge, supportive networking and needs assessment among Lynch Syndrome patients and their family members. The patient conference was designed utilizing the conceptual framework of action research. Paired pre- and post-conference surveys were administered to 44 conference participants anonymously to assess patient-reported disease knowledge and education needs. A multidisciplinary team of expert providers utilized a variety of educational formats during the one-day conference. Four main focus areas were: genetic testing, surveillance/prevention, living with Lynch Syndrome, and update on research. Thirty-two participants (73%) completed the pre-conference, and 28 (64%) participants completed the post-conference surveys. Nineteen respondents were affected and the remaining were unaffected. The scores of the disease-knowledge items significantly increased from 84% pre- to 92% post-conference (p = 0.012). Patients reported a high level of satisfaction and identified further knowledge needs in nutrition (71%), surveillance/prevention options (71%), support groups (36%), cancer risk assessment (32%), active role in medical care (32%), and research opportunities (5%). Our experience with a dedicated patient education conference focused on Lynch Syndrome demonstrated that such an educational format is effective for updating or reinforcing disease knowledge, for identifying patient-reported unmet educational needs, as well as for peer-support.

Whole genome sequencing of Brucella melitensis isolated from 57 patients in Germany reveals high diversity in strains from Middle East.

PubMed

Georgi, Enrico; Walter, Mathias C; Pfalzgraf, Marie-Theres; Northoff, Bernd H; Holdt, Lesca M; Scholz, Holger C; Zoeller, Lothar; Zange, Sabine; Antwerpen, Markus H

2017-01-01

Brucellosis, a worldwide common bacterial zoonotic disease, has become quite rare in Northern and Western Europe. However, since 2014 a significant increase of imported infections caused by Brucella (B.) melitensis has been noticed in Germany. Patients predominantly originated from Middle East including Turkey and Syria. These circumstances afforded an opportunity to gain insights into the population structure of Brucella strains. Brucella-isolates from 57 patients were recovered between January 2014 and June 2016 with culture confirmed brucellosis by the National Consultant Laboratory for Brucella. Their whole genome sequences were generated using the Illumina MiSeq platform. A whole genome-based SNP typing assay was developed in order to resolve geographically attributed genetic clusters. Results were compared to MLVA typing results, the current gold-standard of Brucella typing. In addition, sequences were examined for possible genetic variation within target regions of molecular diagnostic assays. Phylogenetic analyses revealed spatial clustering and distinguished strains from different patients in either case, whereas multiple isolates from a single patient or technical replicates showed identical SNP and MLVA profiles. By including WGS data from the NCBI database, five major genotypes were identified. Notably, strains originating from Turkey showed a high diversity and grouped into seven subclusters of genotype II. MLVA analysis congruently clustered all isolates and predominantly matched the East Mediterranean genetic clade. This study confirms whole-genome based SNP-analysis as a powerful tool for accurate typing of B. melitensis. Furthermore it allows special allocation and therefore provides useful information on the geographic origin for trace-back analysis. However, the lack of reliable metadata in public databases often prevents a resolution below geographic regions or country levels and corresponding precise trace-back analysis. Once this obstacle is resolved, WGS-derived bacterial typing adds an important method to complement epidemiological surveys during outbreak investigations. This is the first report of a detailed genetic investigation of an extensive collection of B. melitensis strains isolated from human cases in Germany.

Uniparental Genetic Heritage of Belarusians: Encounter of Rare Middle Eastern Matrilineages with a Central European Mitochondrial DNA Pool

PubMed Central

Kushniarevich, Alena; Sivitskaya, Larysa; Danilenko, Nina; Novogrodskii, Tadeush; Tsybovsky, Iosif; Kiseleva, Anna; Kotova, Svetlana; Chaubey, Gyaneshwer; Metspalu, Ene; Sahakyan, Hovhannes; Bahmanimehr, Ardeshir; Reidla, Maere; Rootsi, Siiri; Parik, Jüri; Reisberg, Tuuli; Achilli, Alessandro; Hooshiar Kashani, Baharak; Gandini, Francesca; Olivieri, Anna; Behar, Doron M.; Torroni, Antonio; Davydenko, Oleg; Villems, Richard

2013-01-01

Ethnic Belarusians make up more than 80% of the nine and half million people inhabiting the Republic of Belarus. Belarusians together with Ukrainians and Russians represent the East Slavic linguistic group, largest both in numbers and territory, inhabiting East Europe alongside Baltic-, Finno-Permic- and Turkic-speaking people. Till date, only a limited number of low resolution genetic studies have been performed on this population. Therefore, with the phylogeographic analysis of 565 Y-chromosomes and 267 mitochondrial DNAs from six well covered geographic sub-regions of Belarus we strove to complement the existing genetic profile of eastern Europeans. Our results reveal that around 80% of the paternal Belarusian gene pool is composed of R1a, I2a and N1c Y-chromosome haplogroups – a profile which is very similar to the two other eastern European populations – Ukrainians and Russians. The maternal Belarusian gene pool encompasses a full range of West Eurasian haplogroups and agrees well with the genetic structure of central-east European populations. Our data attest that latitudinal gradients characterize the variation of the uniparentally transmitted gene pools of modern Belarusians. In particular, the Y-chromosome reflects movements of people in central-east Europe, starting probably as early as the beginning of the Holocene. Furthermore, the matrilineal legacy of Belarusians retains two rare mitochondrial DNA haplogroups, N1a3 and N3, whose phylogeographies were explored in detail after de novo sequencing of 20 and 13 complete mitogenomes, respectively, from all over Eurasia. Our phylogeographic analyses reveal that two mitochondrial DNA lineages, N3 and N1a3, both of Middle Eastern origin, might mark distinct events of matrilineal gene flow to Europe: during the mid-Holocene period and around the Pleistocene-Holocene transition, respectively. PMID:23785503

Multigene Assessment of the Species Boundaries and Sexual Status of the Basidiomycetous Yeasts Cryptococcus flavescens and C. terrestris (Tremellales)

PubMed Central

Sharma, Lav; Carvalho, Cláudia; Fonseca, Álvaro

2015-01-01

Cryptococcus flavescens and C. terrestris are phenotypically indistinguishable sister species that belong to the order Tremellales (Tremellomycetes, Basidiomycota) and which may be mistaken for C. laurentii based on phenotype. Phylogenetic separation between C. flavescens and C. terrestris was based on rDNA sequence analyses, but very little is known on their intraspecific genetic variability or propensity for sexual reproduction. We studied 59 strains from different substrates and geographic locations, and used a multilocus sequencing (MLS) approach complemented with the sequencing of mating type (MAT) genes to assess genetic variation and reexamine the boundaries of the two species, as well as their sexual status. The following five loci were chosen for MLS: the rDNA ITS-LSU region, the rDNA IGS1 spacer, and fragments of the genes encoding the largest subunit of RNA polymerase II (RPB1), the translation elongation factor 1 alpha (TEF1) and the p21-activated protein kinase (STE20). Phylogenetic network analyses confirmed the genetic separation of the two species and revealed two additional cryptic species, for which the names Cryptococcus baii and C. ruineniae are proposed. Further analyses of the data revealed a high degree of genetic heterogeneity within C. flavescens as well as evidence for recombination between lineages detected for this species. Strains of C. terrestris displayed higher levels of similarity in all analysed genes and appear to make up a single recombining group. The two MAT genes (STE3 and SXI1/SXI2) sequenced for C. flavescens strains confirmed the potential for sexual reproduction and suggest the presence of a tetrapolar mating system with a biallelic pheromone/receptor locus and a multiallelic HD locus. In C. terrestris we could only sequence STE3, which revealed a biallelic P/R locus. In spite of the strong evidence for sexual recombination in the two species, attempts at mating compatible strains of both species on culture media were unsuccessful. PMID:25811603

Marketplace Clinics Complementing Diabetes Care for Urban Residing American Indians

PubMed Central

Rick, Robert; Hoye, Robert E.; Thron, Raymond W.; Kumar, Vibha

2017-01-01

Introduction: For several decades, the Minneapolis American Indian population has experienced limited health care access and threefold diabetes health disparity. As part of an urban health initiative, the marketplace clinics located in nearby CVS, Target, and Supervalu stores committed financial support, providers, certified educators, and pharmacy staff for a community-based diabetes support group. Objectives: To measure the extent to which collaborating marketplace clinics and the community-based support group expanded diabetes care and provided self-management education for this largely urban Indian neighborhood. Methods: A controlled quasi-experimental study and 3-years retrospective analysis of secondary data were used to test whether the Minneapolis marketplace clinics and the community diabetes support group participants (n = 48) had improved diabetes health outcomes relative to the comparison group (n = 87). The marketplace complemented intervention group employed motivational interviewing and the patient activation measure (PAM®) in coaching diabetes self-care and behavioral modification. The federally funded comparison group received only basic self-management education. Results: T tests and effect sizes were used to quantify the difference between the study intervention and comparison groups. Statistical significance was determined for the following outcome variables: A1C (P < .01), body mass index (P < .04), and PAM® (P < .001). Discussion: Includes strengths, limitations, and future study recommendations. Conclusions: Positive effects of marketplace clinics and community health complementation were found with regard to improved blood glucose control, weight loss, and healthful lifestyle adaptation. Primary care and community health improvements could be realized by incorporating patient activation with diabetes prevention programs for the urban Indian two-thirds majority of the United States 5 million American Indian population. PMID:28707507

The Number of X Chromosomes Causes Sex Differences in Adiposity in Mice

PubMed Central

Chen, Xuqi; McClusky, Rebecca; Chen, Jenny; Beaven, Simon W.; Tontonoz, Peter

2012-01-01

Sexual dimorphism in body weight, fat distribution, and metabolic disease has been attributed largely to differential effects of male and female gonadal hormones. Here, we report that the number of X chromosomes within cells also contributes to these sex differences. We employed a unique mouse model, known as the “four core genotypes,” to distinguish between effects of gonadal sex (testes or ovaries) and sex chromosomes (XX or XY). With this model, we produced gonadal male and female mice carrying XX or XY sex chromosome complements. Mice were gonadectomized to remove the acute effects of gonadal hormones and to uncover effects of sex chromosome complement on obesity. Mice with XX sex chromosomes (relative to XY), regardless of their type of gonad, had up to 2-fold increased adiposity and greater food intake during daylight hours, when mice are normally inactive. Mice with two X chromosomes also had accelerated weight gain on a high fat diet and developed fatty liver and elevated lipid and insulin levels. Further genetic studies with mice carrying XO and XXY chromosome complements revealed that the differences between XX and XY mice are attributable to dosage of the X chromosome, rather than effects of the Y chromosome. A subset of genes that escape X chromosome inactivation exhibited higher expression levels in adipose tissue and liver of XX compared to XY mice, and may contribute to the sex differences in obesity. Overall, our study is the first to identify sex chromosome complement, a factor distinguishing all male and female cells, as a cause of sex differences in obesity and metabolism. PMID:22589744