Identifying Rare FHB-Resistant Segregants in Intransigent Backcross and F2 Winter Wheat Populations.

PubMed

Clark, Anthony J; Sarti-Dvorjak, Daniela; Brown-Guedira, Gina; Dong, Yanhong; Baik, Byung-Kee; Van Sanford, David A

2016-01-01

Fusarium head blight (FHB), caused mainly by Fusarium graminearum Schwabe [telomorph: Gibberella zeae Schwein.(Petch)] in the US, is one of the most destructive diseases of wheat (Triticum aestivum L. and T. durum L.). Infected grain is usually contaminated with deoxynivalenol (DON), a serious mycotoxin. The challenge in FHB resistance breeding is combining resistance with superior agronomic and quality characteristics. Exotic QTL are widely used to improve FHB resistance. Success depends on the genetic background into which the QTL are introgressed, whether through backcrossing or forward crossing; QTL expression is impossible to predict. In this study four high-yielding soft red winter wheat breeding lines with little or no scab resistance were each crossed to a donor parent (VA01W-476) with resistance alleles at two QTL: Fhb1 (chromosome 3BS) and QFhs.nau-2DL (chromosome 2DL) to generate backcross and F2 progeny. F2 individuals were genotyped and assigned to 4 groups according to presence/ absence of resistance alleles at one or both QTL. The effectiveness of these QTL in reducing FHB rating, incidence, index, severity, Fusarium-damaged kernels (FDK) and DON, in F2-derived lines was assessed over 2 years. Fhb1 showed an average reduction in DON of 17.5%, and conferred significant resistance in 3 of 4 populations. QFhs.nau-2DL reduced DON 6.7% on average and conferred significant resistance in 2 of 4 populations. The combination of Fhb1 and QFhs.nau-2DL resistance reduced DON 25.5% across all populations. Double resistant lines had significantly reduced DON compared to double susceptible lines in 3 populations. Backcross derived progeny were planted in replicated yield trials (2011 and 2012) and in a scab nursery in 2012. Several top yielding lines performed well in the scab nursery, with acceptable DON concentrations, even though the average effect of either QTL in this population was not significant. Population selection is often viewed as an "all or nothing

The backcross sterility technique

Treesearch

V. C. Mastro; A. Pellegrini-Toole

1991-01-01

The sterile insect technique (SIT) and the induced inherited (F1) sterility technique have been investigated for a number of lepidopterous pests, including the gypsy moths. Another technique, backcross sterility, which could potentially prove as or more useful for control of pest species has been developed for the control of only one lepidopteran...

Evaluation of cotton leaf curl virus resistance in BC1, BC2, and BC3 progenies from an interspecific cross between Gossypium arboreum and Gossypium hirsutum.

PubMed

Nazeer, Wajad; Tipu, Abdul Latif; Ahmad, Saghir; Mahmood, Khalid; Mahmood, Abid; Zhou, Baoliang

2014-01-01

Cotton leaf curl virus disease (CLCuD) is an important constraint to cotton production. The resistance of G. arboreum to this devastating disease is well documented. In the present investigation, we explored the possibility of transferring genes for resistance to CLCuD from G. arboreum (2n = 26) cv 15-Mollisoni into G. hirsutum (2n = 52) cv CRSM-38 through conventional breeding. We investigated the cytology of the BC1 to BC3 progenies of direct and reciprocal crosses of G. arboreum and G. hirsutum and evaluated their resistance to CLCuD. The F1 progenies were completely resistant to this disease, while a decrease in resistance was observed in all backcross generations. As backcrossing progressed, the disease incidence increased in BC1 (1.7-2.0%), BC2 (1.8-4.0%), and BC3 (4.2-7.0%). However, the disease incidence was much lower than that of the check variety CIM-496, with a CLCuD incidence of 96%. Additionally, the disease incidence percentage was lower in the direct cross 2(G. arboreum)×G. hirsutum than in that of G. hirsutum×G. arboreum. Phenotypic resemblance of BC1 ∼BC3 progenies to G. arboreum confirmed the success of cross between the two species. Cytological studies of CLCuD-resistant plants revealed that the frequency of univalents and multivalents was high in BC1, with sterile or partially fertile plants, but low in BC2 (in both combinations), with shy bearing plants. In BC3, most of the plants exhibited normal bearing ability due to the high frequency of chromosome associations (bivalents). The assessment of CLCuD through grafting showed that the BC1 to BC3 progenies were highly resistant to this disease. Thus, this study successfully demonstrates the possibility of introgressing CLCuD resistance genes from G. arboreum to G. hirsutum.

Transfer of Dicamba Tolerance from Sinapis arvensis to Brassica napus via Embryo Rescue and Recurrent Backcross Breeding.

PubMed

Jugulam, M; Ziauddin, Asma; So, Kenny K Y; Chen, Shu; Hall, J Christopher

2015-01-01

Auxinic herbicides (e.g. dicamba) are extensively used in agriculture to selectively control broadleaf weeds. Although cultivated species of Brassicaceae (e.g. Canola) are susceptible to auxinic herbicides, some biotypes of Sinapis arvensis (wild mustard) were found dicamba resistant in Canada. In this research, dicamba tolerance from wild mustard was introgressed into canola through embryo rescue followed by conventional breeding. Intergeneric hybrids between S. arvensis (2n = 18) and B. napus (2n = 38) were produced through embryo rescue. Embryo formation and hybrid plant regeneration was achieved. Transfer of dicamba tolerance from S. arvensis into the hybrid plants was determined by molecular analysis and at the whole plant level. Dicamba tolerance was introgressed into B. napus by backcrossing for seven generations. Homozygous dicamba-tolerant B. napus lines were identified. The ploidy of the hybrid progeny was assessed by flow cytometry. Finally, introgression of the piece of DNA possibly containing the dicamba tolerance gene into B. napus was confirmed using florescence in situ hybridization (FISH). This research demonstrates for the first time stable introgression of dicamba tolerance from S. arvensis into B. napus via in vitro embryo rescue followed by repeated backcross breeding. Creation of dicamba-tolerant B. napus varieties by this approach may have potential to provide options to growers to choose a desirable herbicide-tolerant technology. Furthermore, adoption of such technology facilitates effective weed control, less tillage, and possibly minimize evolution of herbicide resistant weeds.

Selection for Reduced Fusarium Ear Rot and Fumonisin Content in Advanced Backcross Maize Lines and Their Topcross Hybrids

USDA-ARS?s Scientific Manuscript database

Backcross breeding is an important method to improve elite cultivars for traits controlled by a small number of loci but has been used less frequently to improve quantitatively controlled traits. Resistances to Fusarium ear rot and contamination by the associated mycotoxin fumonisin in maize are qua...

Evaluating hybrid poplar rooting. II. backcross breeding method exhibits exceptional promise

Treesearch

Ronald S., Jr. Zalesny; Don E. Riemenschneider; Richard B. Hall

2002-01-01

Backcross breeding uses two crosses to create genotypes with improved traits. The first cross establishes an F1 population, which is then used as the female parent in a set of second crosses. The male parent of the second cross is often a genotype well-adapted to local environments. A currently investigated backcross population is the result of...

Genetic dissection of growth, wood basic density and gene expression in interspecific backcrosses of Eucalyptus grandis and E. urophylla

PubMed Central

2012-01-01

Background F1 hybrid clones of Eucalyptus grandis and E. urophylla are widely grown for pulp and paper production in tropical and subtropical regions. Volume growth and wood quality are priority objectives in Eucalyptus tree improvement. The molecular basis of quantitative variation and trait expression in eucalypt hybrids, however, remains largely unknown. The recent availability of a draft genome sequence (http://www.phytozome.net) and genome-wide genotyping platforms, combined with high levels of genetic variation and high linkage disequilibrium in hybrid crosses, greatly facilitate the detection of quantitative trait loci (QTLs) as well as underlying candidate genes for growth and wood property traits. In this study, we used Diversity Arrays Technology markers to assess the genetic architecture of volume growth (diameter at breast height, DBH) and wood basic density in four-year-old progeny of an interspecific backcross pedigree of E. grandis and E. urophylla. In addition, we used Illumina RNA-Seq expression profiling in the E. urophylla backcross family to identify cis- and trans-acting polymorphisms (eQTLs) affecting transcript abundance of genes underlying QTLs for wood basic density. Results A total of five QTLs for DBH and 12 for wood basic density were identified in the two backcross families. Individual QTLs for DBH and wood basic density explained 3.1 to 12.2% of phenotypic variation. Candidate genes underlying QTLs for wood basic density on linkage groups 8 and 9 were found to share trans-acting eQTLs located on linkage groups 4 and 10, which in turn coincided with QTLs for wood basic density suggesting that these QTLs represent segregating components of an underlying transcriptional network. Conclusion This is the first demonstration of the use of next-generation expression profiling to quantify transcript abundance in a segregating tree population and identify candidate genes potentially affecting wood property variation. The QTLs identified in this

Effect of calving distribution on beef cattle progeny performance.

PubMed

Funston, R N; Musgrave, J A; Meyer, T L; Larson, D M

2012-12-01

Records collected between 1997 and 2010 were used to determine the effect of calving period on heifer (n = 1,019) and steer (n = 771) progeny from the Gudmundsen Sandhills Laboratory, Whitman, NE. Progeny were classified as being born in the first, second, or third 21-d period of the spring calving season within year. Heifer birth BW was lightest (P < 0.01) for heifers born in the first period. Birth to weaning ADG tended (P = 0.10) to be least for heifers born in the first calving period; however, weaning BW decreased (P = 0.03) with advancing calving period. Weaning to prebreeding ADG tended (P = 0.07) to be least for heifers born in the first period; however, prebreeding BW was greatest (P < 0.01) for calves born in the first period. Heifer ADG from the beginning of the breeding season to pregnancy diagnosis was greater (P = 0.03) for heifers born in the third vs. first calving period. Heifers cycling at the beginning of the breeding season decreased (P < 0.01) with advancing calving date (70, 58, and 39%, respectively) and 45 d pregnancy rates were lowest (P = 0.02) for heifers born in the third calving period (90, 86, and 78%, respectively). Birth date of the first calf of the heifer and birth BW decreased (P < 0.01) if the heifer was born in the first calving period. First calf progeny had the greatest (P ≤ 0.10) weaning BW if born to a heifer born in the first calving period. As steer calving period advanced, weaning BW decreased (P < 0.01). Calving period did not affect (P = 0.81) feedlot ADG. As calving period advanced, HCW, marbling score, and yield grade decreased (P < 0.01). The percentage of steers grading USDA small marbling was not affected (P = 0.13) by calving period; however, the percentage of steers grading USDA modest marbling or greater and the total carcass value declined (P ≤ 0.01) as calving period advanced. Heifer calves born during the first 21 d of the spring calving season had greater weaning, prebreeding, and precalving BW; greater

Advanced backcross QTL mapping of resistance to Fusarium head blight and plant morphological traits in a Triticum macha × T. aestivum population.

PubMed

Buerstmayr, Maria; Lemmens, Marc; Steiner, Barbara; Buerstmayr, Hermann

2011-07-01

While many reports on genetic analysis of Fusarium head blight (FHB) resistance in bread wheat have been published during the past decade, only limited information is available on FHB resistance derived from wheat relatives. In this contribution, we report on the genetic analysis of FHB resistance derived from Triticum macha (Georgian spelt wheat). As the origin of T. macha is in the Caucasian region, it is supposed that its FHB resistance differs from other well-investigated resistance sources. To introduce valuable alleles from the landrace T. macha into a modern genetic background, we adopted an advanced backcross QTL mapping scheme. A backcross-derived recombinant-inbred line population of 321 BC(2)F(3) lines was developed from a cross of T. macha with the Austrian winter wheat cultivar Furore. The population was evaluated for Fusarium resistance in seven field experiments during four seasons using artificial inoculations. A total of 300 lines of the population were genetically fingerprinted using SSR and AFLP markers. The resulting linkage map covered 33 linkage groups with 560 markers. Five novel FHB-resistance QTL, all descending from T. macha, were found on four chromosomes (2A, 2B, 5A, 5B). Several QTL for morphological and developmental traits were mapped in the same population, which partly overlapped with FHB-resistance QTL. Only the 2BL FHB-resistance QTL co-located with a plant height QTL. The largest-effect FHB-resistance QTL in this population mapped at the spelt-type locus on chromosome 5A and was associated with the wild-type allele q, but it is unclear whether q has a pleiotropic effect on FHB resistance or is closely linked to a nearby resistance QTL.

Hybrid sterility and evolution in Hawaiian Drosophila: differential gene and allele-specific expression analysis of backcross males.

PubMed

Brill, E; Kang, L; Michalak, K; Michalak, P; Price, D K

2016-08-01

The Hawaiian Drosophila are an iconic example of sequential colonization, adaptive radiation and speciation on islands. Genetic and phenotypic analysis of closely related species pairs that exhibit incomplete reproductive isolation can provide insights into the mechanisms of speciation. Drosophila silvestris from Hawai'i Island and Drosophila planitibia from Maui are two closely related allopatric Hawaiian picture-winged Drosophila that produce sterile F1 males but fertile F1 females, a pattern consistent with Haldane's rule. Backcrossing F1 hybrid females between these two species to parental species gives rise to recombinant males with three distinct sperm phenotypes despite a similar genomic background: motile sperm, no sperm (sterile), and immotile sperm. We found that these three reproductive morphologies of backcross hybrid males produce divergent gene expression profiles in testes, as measured with RNA sequencing. There were a total of 71 genes significantly differentially expressed between backcross males with no sperm compared with those backcross males with motile sperm and immotile sperm, but no significant differential gene expression between backcross males with motile sperm and backcross males with immotile sperm. All of these genes were underexpressed in males with no sperm, including a number of genes with previously known activities in adult testis. An allele-specific expression analysis showed overwhelmingly more cis-divergent than trans-divergent genes, with no significant difference in the ratio of cis- and trans-divergent genes among the sperm phenotypes. Overall, the results indicate that the regulation of gene expression involved in sperm production likely diverged relatively rapidly between these two closely related species.

Hd6, a rice quantitative trait locus involved in photoperiod sensitivity, encodes the α subunit of protein kinase CK2

PubMed Central

Takahashi, Yuji; Shomura, Ayahiko; Sasaki, Takuji; Yano, Masahiro

2001-01-01

Hd6 is a quantitative trait locus involved in rice photoperiod sensitivity. It was detected in backcross progeny derived from a cross between the japonica variety Nipponbare and the indica variety Kasalath. To isolate a gene at Hd6, we used a large segregating population for the high-resolution and fine-scale mapping of Hd6 and constructed genomic clone contigs around the Hd6 region. Linkage analysis with P1-derived artificial chromosome clone-derived DNA markers delimited Hd6 to a 26.4-kb genomic region. We identified a gene encoding the α subunit of protein kinase CK2 (CK2α) in this region. The Nipponbare allele of CK2α contains a premature stop codon, and the resulting truncated product is undoubtedly nonfunctional. Genetic complementation analysis revealed that the Kasalath allele of CK2α increases days-to-heading. Map-based cloning with advanced backcross progeny enabled us to identify a gene underlying a quantitative trait locus even though it exhibited a relatively small effect on the phenotype. PMID:11416158

A score-statistic approach for determining threshold values in QTL mapping.

PubMed

Kao, Chen-Hung; Ho, Hsiang-An

2012-06-01

Issues in determining the threshold values of QTL mapping are often investigated for the backcross and F2 populations with relatively simple genome structures so far. The investigations of these issues in the progeny populations after F2 (advanced populations) with relatively more complicated genomes are generally inadequate. As these advanced populations have been well implemented in QTL mapping, it is important to address these issues for them in more details. Due to an increasing number of meiosis cycle, the genomes of the advanced populations can be very different from the backcross and F2 genomes. Therefore, special devices that consider the specific genome structures present in the advanced populations are required to resolve these issues. By considering the differences in genome structure between populations, we formulate more general score test statistics and gaussian processes to evaluate their threshold values. In general, we found that, given a significance level and a genome size, threshold values for QTL detection are higher in the denser marker maps and in the more advanced populations. Simulations were performed to validate our approach.

Genetic potential of common bean progenies selected for crude fiber content obtained through different breeding methods.

PubMed

Júnior, V A P; Melo, P G S; Pereira, H S; Bassinello, P Z; Melo, L C

2015-05-29

Gastrointestinal health is of great importance due to the increasing consumption of functional foods, especially those concern-ing diets rich in fiber content. The common bean has been valorized as a nutritious food due to its appreciable fiber content and the fact that it is consumed in many countries. The current study aimed to evaluate and compare the genetic potential of common bean progenies of the carioca group, developed through different breeding methods, for crude fiber content. The progenies originated through hybridization of two advanced strains, CNFC 7812 and CNFC 7829, up to the F7 generation using three breeding methods: bulk-population, bulk within F2 families, and single seed descent. Fifteen F8 progenies were evaluated in each method, as well as two check cultivars and both parents, us-ing a 7 x 7 simple lattice design, with experimental plots comprised of two 4-m long rows. Field trials were conducted in eleven environments encompassing four Brazilian states and three different sowing times during 2009 and 2010. Estimates of genetic parameters indicate differences among the breeding methods, which seem to be related to the different processes for sampling the advanced progenies inherent to each method, given that the trait in question is not subject to natural selection. Variability amongst progenies occurred within the three breeding methods and there was also a significant effect of environment on the progeny for all methods. Progenies developed by bulk-population attained the highest estimates of genetic parameters, had less interaction with the environment, and greater variability.

The importance of site quality to backcross chestnut establishment success

Treesearch

C.C. Pinchot; A.A. Royo; M.P. Peters; S.E. Schlarbaum; S.L. Anagnostakis

2017-01-01

Short-term studies show that American chestnut (Castanea dentata) grows faster on mesic compared to xeric sites. Long-term impacts of site quality and corresponding moisture and nutrient availability on backcross chestnut establishment success and resistance to the chestnut blight fungus, Cryphonectria parasitica, however, have...

Recurrent parent genome recovery analysis in a marker-assisted backcrossing program of rice (Oryza sativa L.).

PubMed

Miah, Gous; Rafii, Mohd Y; Ismail, Mohd R; Puteh, Adam B; Rahim, Harun A; Latif, Mohammad A

2015-02-01

Backcross breeding is the most commonly used method for incorporating a blast resistance gene into a rice cultivar. Linkage between the resistance gene and undesirable units can persist for many generations of backcrossing. Marker-assisted backcrossing (MABC) along with marker-assisted selection (MAS) contributes immensely to overcome the main limitation of the conventional breeding and accelerates recurrent parent genome (RPG) recovery. The MABC approach was employed to incorporate (a) blast resistance gene(s) from the donor parent Pongsu Seribu 1, the blast-resistant local variety in Malaysia, into the genetic background of MR219, a popular high-yielding rice variety that is blast susceptible, to develop a blast-resistant MR219 improved variety. In this perspective, the recurrent parent genome recovery was analyzed in early generations of backcrossing using simple sequence repeat (SSR) markers. Out of 375 SSR markers, 70 markers were found polymorphic between the parents, and these markers were used to evaluate the plants in subsequent generations. Background analysis revealed that the extent of RPG recovery ranged from 75.40% to 91.3% and from 80.40% to 96.70% in BC1F1 and BC2F1 generations, respectively. In this study, the recurrent parent genome content in the selected BC2F2 lines ranged from 92.7% to 97.7%. The average proportion of the recurrent parent in the selected improved line was 95.98%. MAS allowed identification of the plants that are more similar to the recurrent parent for the loci evaluated in backcross generations. The application of MAS with the MABC breeding program accelerated the recovery of the RP genome, reducing the number of generations and the time for incorporating resistance against rice blast. Copyright © 2014 Académie des sciences. Published by Elsevier SAS. All rights reserved.

Identification of introgressed alien chromosome segments associated with grain quality in Oryza rufipogon x MR219 advanced breeding lines using SSR markers.

PubMed

Fasahat, P; Muhammad, K; Abdullah, A; Wickneswari, R

2012-09-26

A limited backcross procedure was utilized to introgress genes associated with grain quality traits from Oryza rufipogon (Accession No. IRGC 105491), a wild rice from Malaysia, to the cultivated rice O. sativa cv. MR219, a popular high yielding Malaysian rice cultivar. A set of 10 BC(2)F(7) progenies were selected based on the field performance and phenotypic appearance in BC(2)F(5) and BC(2)F(6) generations, which initially started with 266 progenies in the BC(2)F(2) generation. These 10 advanced breeding lines are similar to each other but differ in several important grain quality traits, which can be traced to O. rufipogon introgressions. Phenotyping and genotyping of BC(2)F(7) variants were considered for QTL analysis. The introgressed lines did not show any significant changes compared to the recurrent parent MR219 for the traits grain density and milled rice percentage. All 10 progenies showed significantly higher head rice percentages (70-88%) than the recurrent parent MR219. Variants G13 and G15 had higher amylose contents than MR219. All variants were analyzed using polymorphic SSR markers. Of the 34 SSR markers, only 18 showed introgression from O. rufipogon for chromosomes 1, 2, 3, 5, 6, 8, 10, and 11. Graphical genotypes were prepared for each variant, and association between the introgression regions and the traits that increased grain quality was visualized. Based on marker trait association, some of the QTLs are stable across environments and genetic backgrounds and could be used universally.

A radon progeny deposition model

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

Rielage, Keith; Elliott, Steven R; Hime, Andrew

2010-12-01

The next generation low-background detectors operating underground aim for unprecedented low levels of radioactive backgrounds. Although the radioactive decays of airborne radon (particularly {sup 222}Rn) and its subsequent progeny present in an experiment are potential backgrounds, also problematic is the deposition of radon progeny on detector materials. Exposure to radon at any stage of assembly of an experiment can result in surface contamination by progeny supported by the long half life (22 y) of {sup 210}Pb on sensitive locations of a detector. An understanding of the potential surface contamination from deposition will enable requirements of radon-reduced air and clean roommore » environments for the assembly of low background experiments. It is known that there are a number of environmental factors that govern the deposition of progeny onto surfaces. However, existing models have not explored the impact of some environmental factors important for low background experiments. A test stand has been constructed to deposit radon progeny on various surfaces under a controlled environment in order to develop a deposition model. Results from this test stand and the resulting deposition model are presented.« less

Estimation of attached and unattached progeny of 222Rn and 220Rn concentration using deposition based progeny sensors.

PubMed

Mehra, Rohit; Bangotra, Pargin; Kaur, Kirandeep; Kanse, Sandeep; Mishra, Rosaline

2015-11-01

The attached and unattached radon and thoron progeny concentrations have been calculated using deposition-based progeny sensors in Mansa, Muktsar, Bathinda and Faridkot districts of Punjab, India. The total (attached + unattached) equilibrium-equivalent (222)Rn concentration (EECRA + U) and total (attached + unattached) equilibrium-equivalent (220)Rn concentration (EECTA + U) were found to vary from 9 to 46 Bqm(-3) and 0.5 to 3.1 Bq m(-3), respectively. The concentrations of attached progeny nuclides for both (222)Rn and (220)Rn have been found to be greater than the unattached progeny nuclides in the dwellings of studied area. An attempt has also been made to assess the effective dose for (222)Rn and (220)Rn in the studied area. The radiation dose originated from (222)Rn and (220)Rn progeny is low and health risk is negligible. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Calibration of CR-39-based thoron progeny device.

PubMed

Fábián, F; Csordás, A; Shahrokhi, A; Somlai, J; Kovács, T

2014-07-01

Radon isotopes and their progenies have proven significant role in respiratory tumour formation. In most cases, the radiological effect of one of the radon isotopes (thoron) and its progenies has been neglected together with its measurement technique; however, latest surveys proved that thoron's existence is expectable in flats and in workplace in Europe. Detectors based on different track detector measurement technologies have recently spread for measuring thoron progenies; however, the calibration is not yet completely elaborated. This study deals with the calibration of the track detector measurement method suitable for measuring thoron progenies using different devices with measurement techniques capable of measuring several progenies (Pylon AB5 and WLx, Sarad EQF 3220). The calibration factor values related to the thoron progeny monitors, the measurement uncertainty, reproducibility and other parameters were found using the calibration chamber. In the future, the effects of the different parameters (aerosol distribution, etc.) will be determined. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Mated Progeny Production Is a Biomarker of Aging in Caenorhabditis elegans

PubMed Central

Pickett, Christopher L.; Dietrich, Nicholas; Chen, Junfang; Xiong, Chengjie; Kornfeld, Kerry

2013-01-01

The relationships between reproduction and aging are important for understanding the mechanisms of aging and evaluating evolutionary theories of aging. To investigate the effects of progeny production on reproductive and somatic aging, we conducted longitudinal studies of Caenorhabditis elegans hermaphrodites. For mated wild-type animals that were not sperm limited and survived past the end of the reproductive period, high levels of cross-progeny production were positively correlated with delayed reproductive and somatic aging. In this group of animals, individuals that generated more cross progeny also reproduced and lived longer than individuals that generated fewer cross progeny. These results indicate that progeny production does not accelerate reproductive or somatic aging. This longitudinal study demonstrated that cumulative cross progeny production through day four is an early-stage biomarker that is a positive predictor of longevity. Furthermore, in mated animals, high levels of early cross progeny production were positively correlated with high levels of late cross progeny production, indicating that early progeny production does not accelerate reproductive aging. The relationships between progeny production and aging were further evaluated by comparing self-fertile hermaphrodites that generated relatively few self progeny with mated hermaphrodites that generated many cross progeny. The timing of age-related somatic degeneration was similar in these groups, suggesting progeny production does not accelerate somatic aging. These studies rigorously define relationships between progeny production, reproductive aging, and somatic aging and identify new biomarkers of C. elegans aging. These results indicate that some mechanisms or pathways control age-related degeneration of both reproductive and somatic tissues in C. elegans. PMID:24142929

Leaf physiology and morphology of Castanea dentata (Marsh) Borkh., Castanea mollissima Blume, and three backcross breeding generations planted in the southern Appalachians, USA

Treesearch

Benjamin O. Knapp; G. Geoff Wang; Stacy L Clark; Lauren S. Pile; Scott E. Schlarbaum

2014-01-01

Backcross breeding programs have been used to transfer disease resistance and other traits from one forest tree species to another in order to meet restoration objectives. Evaluating the field performance of such material is critical for determining the success of breeding programs. In eastern North America, The American Chestnut Foundation has a backcross breeding...

Cytoplasmic male sterility contributes to hybrid incompatibility between subspecies of Arabidopsis lyrata.

PubMed

Aalto, Esa A; Koelewijn, Hans-Peter; Savolainen, Outi

2013-10-03

In crosses between evolutionarily diverged populations, genomic incompatibilities may result in sterile hybrids, indicating evolution of reproductive isolation. In several plant families, crosses within a population can also lead to male sterile progeny because of conflict between the maternally and biparentally inherited genomes. We examined hybrid fertility between subspecies of the perennial outcrossing self-incompatible Lyrate rockcress (Arabidopsis lyrata) in large reciprocal F2 progenies and three generations of backcrosses. In one of the reciprocal F2 progenies, almost one-fourth of the plants were male-sterile. Correspondingly, almost one-half of the plants in one of the four reciprocal backcross progenies expressed male sterility. In an additional four independent F2 and backcross families, three segregated male sterility. The observed asymmetrical hybrid incompatibility is attributable to male sterility factors in one cytoplasm, for which the other population lacks effective fertility restorers. Genotyping of 96 molecular markers and quantitative trait locus mapping revealed that only 60% of the plants having the male sterile cytoplasm and lacking the corresponding restorers were phenotypically male-sterile. Genotyping data showed that there is only one restorer locus, which mapped to a 600-kb interval at the top of chromosome 2 in a region containing a cluster of pentatricopeptide repeat genes. Male fertility showed no trade-off with seed production. We discuss the role of cytoplasm and genomic conflict in incipient speciation and conclude that cytoplasmic male sterility-lowering hybrid fitness is a transient effect with limited potential to form permanent reproductive barriers between diverged populations of hermaphrodite self-incompatible species.

QTL analysis of cotton fiber length in advanced backcross populations derived from a cross between Gossypium hirsutum and G. mustelinum.

PubMed

Wang, Baohua; Draye, Xavier; Zhuang, Zhimin; Zhang, Zhengsheng; Liu, Min; Lubbers, Edward L; Jones, Don; May, O Lloyd; Paterson, Andrew H; Chee, Peng W

2017-06-01

QTLs for fiber length mapped in three generations of advanced backcross populations derived from crossing Gossypium hirsutum and Gossypium mustelinum showed opportunities to improve elite cottons by introgression from wild relatives. The molecular basis of cotton fiber length in crosses between Gossypium hirsutum and Gossypium mustelinum was dissected using 21 BC 3 F 2 and 12 corresponding BC 3 F 2:3 and BC 3 F 2:4 families. Sixty-five quantitative trait loci (QTLs) were detected by one-way analysis of variance. The QTL numbers detected for upper-half mean length (UHM), fiber uniformity index (UI), and short fiber content (SFC) were 19, 20, and 26 respectively. Twenty-three of the 65 QTLs could be detected at least twice near adjacent markers in the same family or near the same markers across different families/generations, and 32 QTLs were detected in both one-way variance analyses and mixed model-based composite interval mapping. G. mustelinum alleles increased UHM and UI and decreased SFC for five, one, and one QTLs, respectively. In addition to the main-effect QTLs, 17 epistatic QTLs were detected which helped to elucidate the genetic basis of cotton fiber length. Significant among-family genotypic effects were detected at 18, 16, and 16 loci for UHM, UI, and SFC, respectively. Six, two, and two loci showed genotype × family interaction for UHM, UI and SFC, respectively, illustrating complexities that might be faced in introgression of exotic germplasm into cultivated cotton. Co-location of many QTLs for UHM, UI, and SFC accounted for correlations among these traits, and selection of these QTLs may improve the three traits simultaneously. The simple sequence repeat (SSR) markers associated with G. mustelinum QTLs will assist breeders in transferring and maintaining valuable traits from this exotic source during cultivar development.

Combining ability of S3 progenies for key agronomic traits in popcorn: comparison of testers in top-crosses.

PubMed

de Lima, V J; do Amaral Junior, A T; Kamphorst, S H; Pena, G F; Leite, J T; Schmitt, K F M; Vittorazzi, C; de Almeida Filho, J E; Mora, F

2016-12-02

The successful development of hybrid cultivars depends on the reliability of estimated combining ability of the parent lines. The objectives of this study were to assess the combining ability of partially inbred S 3 families of popcorn derived from the open-pollinated variety UENF 14, via top-crosses with four testers, and to compare the testers for their ability to discriminate the S 3 progenies. The experiment was conducted in the 2015/2016 crop season, in an incomplete-block (Lattice) design with three replications. The following agronomic traits were evaluated: average plant height, grain yield (GY), popping expansion (PE), and expanded popcorn volume per hectare. The top-cross hybrid, originating from the BRS-Angela vs S 3 progeny 10 combination, was indicated as promising, showing high values for specific combining ability for GY and PE. For the S 3 progenies that showed high and positive GCA values for GY and PE, the continuity of the breeding program is recommended, with the advance of self-pollination generations. Fasoulas' differentiation index discriminated the BRS-Angela tester as the most suitable for identifying the superior progenies.

Height growth in western white pine progenies

Treesearch

G. E. Rehfeldt; R. J. Steinhoff

1970-01-01

Heights of 31 progenies of western white pines from four geographic localities and four crosses between localities were assessed on 14-year-old trees at two sites. Differences in height among individual progenies were detected but could not be related to localities or crosses between localities. Although differential effects of sites on tree height became apparent...

Progeny testing: proceedings of servicewide genetics workshop

Treesearch

Dick Miller

1984-01-01

The primary objective of this workshop was to discuss in detail the state- of-the-art of progeny testing. All aspects, from setting objectives through data collection and analysis, was be covered. We all know progeny testing is a highly technical phase of our tree improvement programs. Each task is critical and must be performed accurately and within a prescribed time...

Comparative analysis of radon, thoron and thoron progeny concentration measurements.

PubMed

Janik, Miroslaw; Tokonami, Shinji; Kranrod, Chutima; Sorimachi, Atsuyuki; Ishikawa, Tetsuo; Hosoda, Masahiro; McLaughlin, James; Chang, Byung-Uck; Kim, Yong Jae

2013-07-01

This study examined correlations between radon, thoron and thoron progeny concentrations based on surveys conducted in several different countries. For this purpose, passive detectors developed or modified by the National Institute of Radiological Sciences (NIRS) were used. Radon and thoron concentrations were measured using passive discriminative radon-thoron detectors. Thoron progeny measurements were conducted using the NIRS-modified detector, originally developed by Zhuo and Iida. Weak correlations were found between radon and thoron as well as between thoron and thoron progeny. The statistical evaluation showed that attention should be paid to the thoron equilibrium factor for calculation of thoron progeny concentrations based on thoron measurements. In addition, this evaluation indicated that radon, thoron and thoron progeny were independent parameters, so it would be difficult to estimate the concentration of one from those of the others.

A genetic map of mouse chromosome 1 near the Lsh-Ity-Bcg disease resistance locus.

PubMed

Mock, B; Krall, M; Blackwell, J; O'Brien, A; Schurr, E; Gros, P; Skamene, E; Potter, M

1990-05-01

Isozyme and restriction fragment length polymorphism (RFLP) analyses of backcross progeny, recombinant inbred strains, and congenic strains of mice positioned eight genetic markers with respect to the Lsh-Ity-Bcg disease resistance locus. Allelic isoforms of Idh-1 and Pep-3 and RFLPs detected by Southern hybridization for Myl-1, Cryg, Vil, Achrg, bcl-2, and Ren-1,2, between BALB/cAnPt and DBA/2NPt mice, were utilized to examine the cosegregation of these markers with the Lsh-Ity-Bcg resistance phenotype in 103 backcross progeny. An additional 47 backcross progeny from a cross between C57BL/10ScSn and B10.L-Lshr/s mice were examined for the cosegregation of Myl-1 and Vil RFLPs with Lsh phenotypic differences. Similarly, BXD recombinant inbred strains were typed for RFLPs upon hybridization with Vil and Achrg. Recombination frequencies generated in the different test systems were statistically similar, and villin (Vil) was identified as the molecular marker closest (1.7 +/- 0.8 cM) to the Lsh-Ity-Bcg locus. Two other DNA sequences, nebulin (Neb) and an anonymous DNA fragment (D2S3), which map to a region of human chromosome 2q that is homologous to proximal mouse chromosome 1, were not closely linked to the Lsh-Ity-Bcg locus. This multipoint linkage analysis of chromosome 1 surrounding the Lsh-Ity-Bcg locus provides a basis for the eventual isolation of the disease gene.

Mapping quantitative trait loci for lint yield and fiber quality across environments in a Gossypium hirsutum × Gossypium barbadense backcross inbred line population.

PubMed

Yu, Jiwen; Zhang, Ke; Li, Shuaiyang; Yu, Shuxun; Zhai, Honghong; Wu, Man; Li, Xingli; Fan, Shuli; Song, Meizhen; Yang, Daigang; Li, Yunhai; Zhang, Jinfa

2013-01-01

Identification of stable quantitative trait loci (QTLs) across different environments and mapping populations is a prerequisite for marker-assisted selection (MAS) for cotton yield and fiber quality. To construct a genetic linkage map and to identify QTLs for fiber quality and yield traits, a backcross inbred line (BIL) population of 146 lines was developed from a cross between Upland cotton (Gossypium hirsutum) and Egyptian cotton (Gossypium barbadense) through two generations of backcrossing using Upland cotton as the recurrent parent followed by four generations of self pollination. The BIL population together with its two parents was tested in five environments representing three major cotton production regions in China. The genetic map spanned a total genetic distance of 2,895 cM and contained 392 polymorphic SSR loci with an average genetic distance of 7.4 cM per marker. A total of 67 QTLs including 28 for fiber quality and 39 for yield and its components were detected on 23 chromosomes, each of which explained 6.65-25.27% of the phenotypic variation. Twenty-nine QTLs were located on the At subgenome originated from a cultivated diploid cotton, while 38 were on the Dt subgenome from an ancestor that does not produce spinnable fibers. Of the eight common QTLs (12%) detected in more than two environments, two were for fiber quality traits including one for fiber strength and one for uniformity, and six for yield and its components including three for lint yield, one for seedcotton yield, one for lint percentage and one for boll weight. QTL clusters for the same traits or different traits were also identified. This research represents one of the first reports using a permanent advanced backcross inbred population of an interspecific hybrid population to identify QTLs for fiber quality and yield traits in cotton across diverse environments. It provides useful information for transferring desirable genes from G. barbadense to G. hirsutum using MAS.

Ponderosa pine progenies: differential response to ultramafic and granitic soils

Treesearch

James L. Jenkinson

1974-01-01

Progenies of nine ponderosa pines native to one granitic and several ultramafic soils in the northern Sierra Nevada were grown on both soil types in a greenhouse. The progenies differed markedly in first-year growth on infertile ultramafic soils, but not on a fertile granitic soil. Growth differences between progenies were primarily related to differences in calcium...

Comparative analysis of radon, thoron and thoron progeny concentration measurements

PubMed Central

Janik, Miroslaw; Tokonami, Shinji; Kranrod, Chutima; Sorimachi, Atsuyuki; Ishikawa, Tetsuo; Hosoda, Masahiro; Mclaughlin, James; Chang, Byung-Uck; Kim, Yong Jae

2013-01-01

This study examined correlations between radon, thoron and thoron progeny concentrations based on surveys conducted in several different countries. For this purpose, passive detectors developed or modified by the National Institute of Radiological Sciences (NIRS) were used. Radon and thoron concentrations were measured using passive discriminative radon-thoron detectors. Thoron progeny measurements were conducted using the NIRS-modified detector, originally developed by Zhuo and Iida. Weak correlations were found between radon and thoron as well as between thoron and thoron progeny. The statistical evaluation showed that attention should be paid to the thoron equilibrium factor for calculation of thoron progeny concentrations based on thoron measurements. In addition, this evaluation indicated that radon, thoron and thoron progeny were independent parameters, so it would be difficult to estimate the concentration of one from those of the others. PMID:23297318

A genetic algorithm application in backcross breeding problem

NASA Astrophysics Data System (ADS)

Carnia, E.; Napitupulu, H.; Supriatna, A. K.

2018-03-01

In this paper we discuss a mathematical model of goat breeding strategy, i.e. the backcrossing breeding. The model is aimed to obtain a strategy in producing better variant of species. In this strategy, a female (doe) of a lesser quality goat, in terms of goat quality is bred with a male (buck) of an exotic goat which has a better goat quality. In this paper we will explore a problem on how to harvest the population optimally. A genetic algorithm (GA) approach will been devised to obtain the solution of the problem. We do several trials of the GA implementation which gives different set of solutions, but relatively close to each other in terms of the resulting total revenue, except a few. Further study need to be done to obtain GA solution that closer to the exact solution.

Transfer of Downy Mildew Resistance from Wild Basil (Ocimum americanum) to Sweet Basil (O. basilicum).

PubMed

Ben-Naim, Yariv; Falach, Lidan; Cohen, Yigal

2018-01-01

Sweet basil (Ocimum basilicum) is susceptible to downy mildew caused by the oomycete foliar pathogen Peronospora belbahrii. No resistant varieties of sweet basil are commercially available. Here, we report on the transfer of resistance gene Pb1 from the highly resistant tetraploid wild basil O. americanum var. americanum (PI 500945, 2n = 4x = 48) to the tetraploid susceptible O. basilicum 'Sweet basil' (2n = 4x = 48). F1 progeny plants derived from the interspecific hybridization PI 500945 × Sweet basil were resistant, indicating that the gene controlling resistance (Pb1) is dominant, but sterile due to the genetic distance between the parents. Despite their sterility, F1 plants were pollinated with the susceptible parent and 115 first backcross generation to the susceptible parent (BCs1) embryos were rescued in vitro. The emerging BCs1 plants segregated, upon inoculation, 5:1 resistant/susceptible, suggesting that resistance in F1 was controlled by a pair of dominant genes (Pb1A and Pb1A'). Thirty-one partially fertile BCs1 plants were self-pollinated to obtain BCs1-F2 or were backcrossed to Sweet basil to obtain the second backcross generation to the susceptible parent (BCs2). In total, 1 BCs1-F2 and 22 BCs2 progenies were obtained. The BCs1-F2 progeny segregated 35:1 resistant/susceptible, as expected from a tetraploid parent with two dominant resistant genes. The 22 BCs2 progenies segregated 1:1 resistant/susceptible (for a BCs1 parent that carried one dominant gene for resistance) or 5:1 (for a BCs1 parent that carried two dominant genes for resistance) at a ratio of 4:1. The data suggest that a pair of dominant genes (Pb1A and Pb1A') residing on a two homeologous chromosomes is responsible for resistance of PI 500945 against P. belbahrii.

Localization of the panhypopituitary dwarf mutation (df) on mouse chromosome 11 in an intersubspecific backcross.

PubMed

Buckwalter, M S; Katz, R W; Camper, S A

1991-07-01

Ames dwarf (df) is an autosomal recessive mutation characterized by severe dwarfism and infertility. This mutation provides a mouse model for panhypopituitarism. The dwarf phenotype results from failure in the differentiation of the cells which produce growth hormone, prolactin, and thyroid stimulating hormone. Using the backcross (DF/B-df/df X CASA/Rk) X DF/B-df/df, we confirmed the assignment of df to mouse chromosome 11 and demonstrated recombination between df and the growth hormone gene. This backcross is an invaluable resource for screening candidate genes for the df mutation. The df locus maps to less than 1 cM distal to Pad-1 (0.85 +/- 0.85 cM). Two new genes localized on mouse chromosome 11, Rpo2-1, and Edp-1, map to a region of conserved synteny with human chromosome 17. The localization of the alpha 1 adrenergic receptor, Adra-1, extends a known region of synteny conservation between mouse chromosome 11 and human chromosome 5, and suggests that a human counterpart to df would map to human chromosome 5.

Distribution of attack by beech scale, Cryptococcus fagisuga, in beech progeny trials

Treesearch

D. Wainhouse; R.S. Howell

1983-01-01

Surveys of beech scale infestation among progeny of single beech trees demonstrated significant variation in susceptibility between the progenies. Relative differences in susceptibility of some progeny were maintained on three different sites in southern England.

Preliminary Mapping of the Western Corn Rootworm (Diabrotica virgifera virgifera) Genome and Quantitative Trait Locus (QTL) Interval Mapping for Growth

USDA-ARS?s Scientific Manuscript database

Preliminary investigations into the organization of the western corn rootworm (Diabrotica virgifera virgifera; WCR) genome have resulted in low to moderate density gender-specific maps constructed from progeny of a backcrossed, short-diapause WCR family. Maps were based upon variation at microsatel...

Introgression of heat shock protein (Hsp70 and sHsp) genes into the Malaysian elite chilli variety Kulai (Capsicum annuum L.) through the application of marker-assisted backcrossing (MAB).

PubMed

Usman, Magaji G; Rafii, Mohd Y; Martini, Mohammad Y; Yusuff, Oladosu A; Ismail, Mohd R; Miah, Gous

2018-03-01

Backcrossing together with simple sequence repeat marker strategy was adopted to improve popular Malaysian chilli Kulai (Capsicum annuum L.) for heat tolerance. The use of molecular markers in backcross breeding and selection contributes significantly to overcoming the main drawbacks such as increase linkage drag and time consumption, in the ancient manual breeding approach (conventional), and speeds up the genome recovery of the recurrent parent. The strategy was adopted to introgress heat shock protein gene(s) from AVPP0702 (C. annuum L.), which are heat-tolerant, into the genetic profile of Kulai, a popular high-yielding chilli but which is heat sensitive. The parents were grown on seed trays, and parental screening was carried out with 252 simple sequence repeat markers. The selected parents were crossed and backcrossed to generate F 1 hybrids and backcross generations. Sixty-eight markers appeared to be polymorphic and were used to assess the backcross generation; BC 1 F 1 , BC 2 F 1 and BC 3 F 1 . The average recipient allele of the selected four BC 1 F 1 plants was 80.75% which were used to produce the BC 2 F 1 generation. BC 1 -P 7 was the best BC 1 F 1 plant because it had the highest recovery at 83.40% and was positive to Hsp-linked markers (Hsp70-u2 and AGi42). After three successive generations of backcrossing, the average genome recovery of the recurrent parent in the selected plants in BC 3 F 1 was 95.37%. Hsp gene expression analysis was carried out on BC 1 F 1 , BC 2 F 1 and BC 3 F 1 selected lines. The Hsp genes were found to be up-regulated when exposed to heat treatment. The pattern of Hsp expression in the backcross generations was similar to that of the donor parent. This confirms the successful introgression of a stress-responsive gene (Hsp) into a Kulai chilli pepper variety. Furthermore, the yield performance viz. plant height, number of fruits, fruit length and weight and total yield of the improved plant were similar with the recurrent

Thoron and thoron progeny measurements in German clay houses.

PubMed

Gierl, S; Meisenberg, O; Feistenauer, P; Tschiersch, J

2014-07-01

In recent years, elevated thoron concentrations were found in houses built of unfired clay. In this study experiments were carried out in 17 traditional and modern clay houses in Germany to obtain an overview of indoor thoron in such houses. Long-term measurements over an 8-week period were performed using a newly developed Unattended Battery-Operated Progeny Measurement Device (UBPM) for measuring thoron progeny. This instrument uses a high-voltage electric field to precipitate radon and thoron progeny on nuclear track detectors. Additional active and passive measurements of radon, thoron and their progeny were performed. The equilibrium equivalent thoron concentration was found to be between 2 and 10 Bq m(-3). Gas concentrations were found to be between 20 and 160 Bq m(-3) for radon and between 10 and 90 Bq m(-3) for thoron 20 cm from the wall. The thoron exposure contributes significantly to the inhalation dose of the dwellers (0.6-4 mSv a(-1)). © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Modeling surface backgrounds from radon progeny plate-out

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

Perumpilly, G.; Guiseppe, V. E.; Snyder, N.

2013-08-08

The next generation low-background detectors operating deep underground aim for unprecedented low levels of radioactive backgrounds. The surface deposition and subsequent implantation of radon progeny in detector materials will be a source of energetic background events. We investigate Monte Carlo and model-based simulations to understand the surface implantation profile of radon progeny. Depending on the material and region of interest of a rare event search, these partial energy depositions can be problematic. Motivated by the use of Ge crystals for the detection of neutrinoless double-beta decay, we wish to understand the detector response of surface backgrounds from radon progeny. Wemore » look at the simulation of surface decays using a validated implantation distribution based on nuclear recoils and a realistic surface texture. Results of the simulations and measured α spectra are presented.« less

Electrical excitability: a spectrum of properties in the progeny of a single embryonic neuroblast.

PubMed Central

Goodman, C S; Pearson, K G; Spitzer, N C

1980-01-01

We have examined the range of some properties of the progeny of a single embryonic precursor cell in the grasshopper. The approximately 100 progeny of this single neuroblast share certain features such as their transmitter and some aspects of their morphology; at the same time, however, they demonstrate a broad spectrum of electrical properties, from spiking to non-spiking neurons. The first-born progeny are spiking neurons with peripheral axons. Many of the progeny, including all of the last-born, do not generate action potentials. The nonspiking progeny are local intraganglionic neurons and appear to compose a major proportion of the progeny of this neuroblast. All of the nonspiking neurons have calcium inward current channels and can make action potentials when outward current channels are blocked. We propose a model for grasshopper neurogenesis based on cell lineage such that (i) certain features (e.g., transmitter) are shared by the progeny of all cell divisions from a single neuroblast, and (ii) other features (e.g., electrical properties) are shared by the progeny of a given birth position (e.g., first versus last born) from all of the neuroblasts. According to this model, the first-born progeny from all neuroblasts are spiking neurons, whereas the last-born are nonspiking. Images PMID:6246499

Genetic-molecular characterization of backcross generations for sexual conversion in papaya (Carica papaya L.).

PubMed

Ramos, H C C; Pereira, M G; Pereira, T N S; Barros, G B A; Ferreguetti, G A

2014-12-04

The low number of improved cultivars limits the expansion of the papaya crop, particularly because of the time required for the development of new varieties using classical procedures. Molecular techniques associated with conventional procedures accelerate this process and allow targeted improvements. Thus, we used microsatellite markers to perform genetic-molecular characterization of papaya genotypes obtained from 3 backcross generations to monitor the inbreeding level and parental genome proportion in the evaluated genotypes. Based on the analysis of 20 microsatellite loci, 77 genotypes were evaluated, 25 of each generation of the backcross program as well as the parental genotypes. The markers analyzed were identified in 11 of the 12 linkage groups established for papaya, ranging from 1 to 4 per linkage group. The average values for the inbreeding coefficient were 0.88 (BC1S4), 0.47 (BC2S3), and 0.63 (BC3S2). Genomic analysis revealed average values of the recurrent parent genome of 82.7% in BC3S2, 64.4% in BC1S4, and 63.9% in BC2S3. Neither the inbreeding level nor the genomic proportions completely followed the expected average values. This demonstrates the significance of molecular analysis when examining different genotype values, given the importance of such information for selection processes in breeding programs.

The first research plantings of third-generation, third-backcross American chestnut (Castanea dentata) in the southeastern United States

Treesearch

Stacy Clark; S.E. Schlarbaum; F,V Saxton

2014-01-01

Production of American chestnut (Castanea dentata) resistant to the chestnut blight fungus (Cryphonectria parasitica) is being conducted currently through traditional breeding and genetic transformation. Sufficient material for field testing is currently available from The American Chestnut Foundation’s backcross breeding program. We planted approximately 4500 chestnut...

All Eggs Are Not Equal: The Maternal Environment Affects Progeny Reproduction and Developmental Fate in Caenorhabditis elegans

PubMed Central

Harvey, Simon C.; Orbidans, Helen E.

2011-01-01

Background Maternal effects on progeny traits are common and these can profoundly alter progeny life history. Maternal effects can be adaptive, representing attempts to appropriately match offspring phenotype to the expected environment and are often mediated via trade-offs between progeny number and quality. Here we have investigated the effect of maternal food availability on progeny life history in the free-living nematode Caenorhabditis elegans. Methodology/Principal Findings The maternal environment affects both reproductive traits and progeny development. Comparisons of the progeny of worms from high and low maternal food environments indicates that low maternal food availability reduces progeny reproduction in good environments, increases progeny reproduction in poor environments and decreases the likelihood that progeny will develop as dauer larvae. These analyses also indicate that the effects on progeny are not a simple consequence of changes in maternal body size, but are associated with an increase in the size of eggs produced by worms at low maternal food availabilities. Conclusions/Significance These results indicate that the maternal environment affects both progeny reproduction and development in C. elegans and therefore that all progeny are not equal. The observed effects are consistent with changes to egg provisioning, which are beneficial in harsh environments, and of changes to progeny development, which are beneficial in harsh environments and detrimental in benign environments. These changes in progeny life history suggest that mothers in poor quality environments may be producing larger eggs that are better suited to poor conditions. PMID:21991370

Variation of the unattached fraction of radon progeny and its contribution to radon exposure.

PubMed

Guo, Lu; Zhang, Lei; Guo, Qiuju

2016-06-01

The unattached fraction of radon progeny is one of the most important factors for radon exposure evaluation through the dosimetric approach. To better understand its level and variation in the real environment, a series of field measurements were carried out indoors and outdoors, and radon equilibrium equivalent concentration was also measured. The dose contribution of unattached radon progeny was evaluated in addition. The results show that no clear variation trend of the unattached fraction of radon progeny is observed in an indoor or outdoor environment. The average unattached fraction of radon progeny for the indoors and outdoors are (8.7  ±  1.6)% and (9.7  ±  2.1)%, respectively. The dose contribution of unattached radon progeny to total radon exposure is some 38.8% in an indoor environment, suggesting the importance of the evaluation on unattached radon progeny.

[Morphometric and stereometric analysis of the masticatory muscles in cases of progeny].

PubMed

Solov'ev, V A; Golikov, D I; Shinkarenko, T V

2009-01-01

The data of microscopic and ultramicroscopric analysis of the muscles of mastication were presented of 12 male patients with progeny. There were determined differentiating peculiarities of muscles fibers of masseter and medial pterygoid in cases of progeny. The results of comperative analysis showed some decreasing of muscular quota and increasing connective tissue's quota; some decreasing muscular fibers' diameters and quantity of blood capillaries; some increasing muscular fibers type I in the muscles of mastication in progeny cases.

Radon progeny in hydrometeors at the earth's surface.

PubMed

Voltaggio, M

2012-07-01

During atmospheric thermal inversions, dew and hoarfrost concentrate gamma emitting radionuclides of the short-lived (222)Rn progeny ((214)Pb and (214)Bi), causing an increase in the total natural gamma background from the ground. To highlight this phenomenon, a volcanic zone of high (222)Rn flux was studied during the winter season 2010-11. High-specific short-lived radon progeny activities up to 122 Bq g(-1) were detected in hydrometeors forming at the earth's surface (ESHs), corresponding to a mean increase of up to 17 % of the normal gamma background value. A theoretical model, depending on radon flux from soil and predicting the radon progeny concentrations in hydrometeors forming at the ESHs is presented. The comparison between model and field data shows a good correspondence. Around nuclear power plants or in nuclear facilities that use automatic NaI or CsI total gamma spectroscopy systems for monitoring radioactive contamination, hydrometeors forming at the ESHs in sites with a high radon flux could represent a relevant source of false alarms of radioactive contamination.

Insulin-like signalling to the maternal germline controls progeny response to osmotic stress

PubMed Central

Burton, Nicholas O.; Furuta, Tokiko; Webster, Amy K.; Kaplan, Rebecca E. W.; Baugh, L. Ryan; Arur, Swathi; Horvitz, H. Robert

2017-01-01

In 1893 August Weismann proposed that information about the environment could not pass from somatic cells to germ cells1, a hypothesis now known as the Weismann barrier. However, recent studies have indicated that parental exposure to environmental stress can modify progeny physiology2–7 and that parental stress can contribute to progeny disorders8. The mechanisms regulating these phenomena are poorly understood. We report that the nematode C. elegans can protect itself from osmotic stress by entering a state of arrested development and can protect its progeny from osmotic stress by increasing the expression of the glycerol biosynthetic enzyme GPDH-2 in progeny. Both of these protective mechanisms are regulated by insulin-like signalling: insulin-like signalling to the intestine regulates developmental arrest, while insulin-like signalling to the maternal germline regulates glycerol metabolism in progeny. Thus, there is a heritable link between insulin-like signalling to the maternal germline and progeny metabolism and gene expression. We speculate that analogous modulation of insulin-like signalling to the germline is responsible for effects of the maternal environment on human diseases that involve insulin signalling, such as obesity and type-2 diabetes8. PMID:28166192

Genetic analysis and identification of SSR markers associated with rice blast disease in a BC2F1 backcross population.

PubMed

Hasan, N; Rafii, M Y; Abdul Rahim, H; Nusaibah, S A; Mazlan, N; Abdullah, S

2017-01-23

Rice (Oryza sativa L.) blast disease is one of the most destructive rice diseases in the world. The fungal pathogen, Magnaporthe oryzae, is the causal agent of rice blast disease. Development of resistant cultivars is the most preferred method to achieve sustainable rice production. However, the effectiveness of resistant cultivars is hindered by the genetic plasticity of the pathogen genome. Therefore, information on genetic resistance and virulence stability are vital to increase our understanding of the molecular basis of blast disease resistance. The present study set out to elucidate the resistance pattern and identify potential simple sequence repeat markers linked with rice blast disease. A backcross population (BC 2 F 1 ), derived from crossing MR264 and Pongsu Seribu 2 (PS2), was developed using marker-assisted backcross breeding. Twelve microsatellite markers carrying the blast resistance gene clearly demonstrated a polymorphic pattern between both parental lines. Among these, two markers, RM206 and RM5961, located on chromosome 11 exhibited the expected 1:1 testcross ratio in the BC 2 F 1 population. The 195 BC 2 F 1 plants inoculated against M. oryzae pathotype P7.2 showed a significantly different distribution in the backcrossed generation and followed Mendelian segregation based on a single-gene model. This indicates that blast resistance in PS2 is governed by a single dominant gene, which is linked to RM206 and RM5961 on chromosome 11. The findings presented in this study could be useful for future blast resistance studies in rice breeding programs.

Analysis of quantitative trait loci affecting chlorophyll content of rice leaves in a double haploid population and two backcross populations.

PubMed

Jiang, Gonghao; Zeng, Jing; He, Yuqing

2014-02-25

Chlorophyll content, one of the most important physiological parameters related to plant photosynthesis, is usually used to predict yield potential. To map the quantitative trait loci (QTLs) underlying the chlorophyll content of rice leaves, a double haploid (DH) population was developed from an indica/japonica (Zhenshan 97/Wuyujing 2) crossing and two backcross populations were established subsequently by backcrossing DH lines with each of their parents. The contents of chlorophyll a and chlorophyll b were determined by using a spectrophotometer to directly measure the leaf chlorophyll extracts. To determine the leaf chlorophyll retention along with maturation, all measurements were performed on the day of heading and were repeated 30 days later. A total of 60 QTLs were resolved for all the traits using these three populations. These QTLs were distributed on 10 rice chromosomes, except chromosomes 5 and 10; the closer the traits, the more clustering of the QTLs residing on common rice chromosomal regions. In general, the majority of QTLs that specify chlorophyll a content also play a role in determining chlorophyll b content. Strangely, chlorophyll content in this study was found mostly to be lacking or to have a negative correlation with yield. In both backcross F1 populations, overdominant (or underdominant) loci were more important than complete or partially dominant loci for main-effect QTLs and epistatic QTLs, thereby supporting previous findings that overdominant effects are the primary genetic basis for depression in inbreeding and heterosis in rice. Copyright © 2013 Elsevier B.V. All rights reserved.

Incorporation of Bacterial Blight Resistance Genes Into Lowland Rice Cultivar Through Marker-Assisted Backcross Breeding.

PubMed

Pradhan, Sharat Kumar; Nayak, Deepak Kumar; Pandit, Elssa; Behera, Lambodar; Anandan, Annamalai; Mukherjee, Arup Kumar; Lenka, Srikanta; Barik, Durga Prasad

2016-07-01

Bacterial blight (BB) of rice caused by Xanthomonas oryzae pv. oryzae is a major disease of rice in many rice growing countries. Pyramided lines carrying two BB resistance gene combinations (Xa21+xa13 and Xa21+xa5) were developed in a lowland cultivar Jalmagna background through backcross breeding by integrating molecular markers. In each backcross generation, markers closely linked to the disease resistance genes were used to select plants possessing the target genes. Background selection was continued in those plants carrying resistant genes until BC(3) generation. Plants having the maximum contribution from the recurrent parent genome were selected in each generation and hybridized with the recipient parent. The BB-pyramided line having the maximum recipient parent genome recovery of 95% was selected among BC3F1 plants and selfed to isolate homozygous BC(3)F(2) plants with different combinations of BB resistance genes. Twenty pyramided lines with two resistance gene combinations exhibited high levels of tolerance against the BB pathogen. In order to confirm the resistance, the pyramided lines were inoculated with different X. oryzae pv. oryzae strains of Odisha for bioassay. The genotypes with combination of two BB resistance genes conferred high levels of resistance to the predominant X. oryzae pv. oryzae isolates prevalent in the region. The pyramided lines showed similarity with the recipient parent with respect to major agro-morphologic traits.

QTLs Analysis and Validation for Fiber Quality Traits Using Maternal Backcross Population in Upland Cotton.

PubMed

Ma, Lingling; Zhao, Yanpeng; Wang, Yumei; Shang, Lianguang; Hua, Jinping

2017-01-01

Cotton fiber is renewable natural fiber source for textile. Improving fiber quality is an essential goal for cotton breeding project. In present study, F 14 recombinant inbred line (RIL) population was backcrossed by the maternal parent to obtain a backcross (BC) population, derived from one Upland cotton hybrid. Three repetitive field trials were performed by randomized complete block design with two replicates in three locations in 2015, together with the BC population, common male parent and the RIL population. Totally, 26 QTLs in BC population explained 5.00-14.17% of phenotype variation (PV) and 37 quantitative trait loci (QTL) were detected in RIL population explaining 5.13-34.00% of PV. Seven common QTLs detected simultaneously in two populations explained PV from 7.69 to 23.05%. A total of 20 QTLs in present study verified the previous results across three environments in 2012. Particularly, qFL-Chr5-2 controlling fiber length on chromosome 5 explained 34.00% of PV, while qFL-Chr5-3 only within a 0.8 cM interval explained 13.93% of PV on average in multiple environments. These stable QTLs explaining great variation offered essential information for marker-assisted selection (MAS) to improve fiber quality traits. Lots of epistasis being detected in both populations acted as one of important genetic compositions of fiber quality traits.

Performance of container-grown seedlings of American chestnut backcross hybrids BC3 F3 generation in central Louisiana

Treesearch

Shi-Jean Susana Sung; Stacy L. Clark; Scott Schlarbaum; Daniel C. Dey; Daniel J. Leduc

2016-01-01

Seedlings from two families of the BC3F3 backcross generation of the American chestnut (Castanea dentata) and Chinese chestnut (C. mollissima) were cultured in 2013 in Missouri using the Root Production Method®, a container-based system used to avoid disease problems associated with...

Mapping quantitative trait loci for yield, yield components and morphological traits in an advanced backcross population between Oryza rufipogon and the Oryza sativa cultivar Jefferson.

PubMed

Thomson, M J; Tai, T H; McClung, A M; Lai, X-H; Hinga, M E; Lobos, K B; Xu, Y; Martinez, C P; McCouch, S R

2003-08-01

An advanced backcross population between an accession of Oryza rufipogon (IRGC 105491) and the U.S. cultivar Jefferson (Oryza sativa ssp. japonica) was developed to identify quantitative trait loci (QTLs) for yield, yield components and morphological traits. The genetic linkage map generated for this population consisted of 153 SSR and RFLP markers with an average interval size of 10.3 cM. Thirteen traits were examined, nine of which were measured in multiple environments. Seventy-six QTLs above an experiment-wise significance threshold of P<0.01 (corresponding to an interval mapping LOD>3.6 or a composite interval mapping LOD>3.9) were identified. For the traits measured in multiple environments, 47% of the QTLs were detected in at least two environments. The O. rufipogon allele was favorable for 53% of the yield and yield component QTLs, including loci for yield, grains per panicle, panicle length, and grain weight. Morphological traits related to the domestication process and/or weedy characteristics, including plant height, shattering, tiller type and awns, were found clustered on chromosomes 1 and 4. Comparisons to previous studies involving wild x cultivated crosses revealed O. rufipogon alleles with stable effects in multiple genetic backgrounds and environments, several of which have not been detected in studies between Oryza sativa cultivars, indicating potentially novel alleles from O. rufipogon. Some O. rufipogon-derived QTLs, however, were in similar regions as previously reported QTLs from Oryza sativa cultivars, providing evidence for conservation of these QTLs across the Oryza genus. In addition, several QTLs for grain weight, plant height, and flowering time were localized to putative homeologous regions in maize where QTLs for these traits have been previously reported, supporting the hypothesis of functional conservation of QTLs across the grasses.

Passive Measurements of Thoron and its Progeny in some Dwellings in Ireland

NASA Astrophysics Data System (ADS)

Choncubhair, Órlaith Ní; Laughlin, James Mc; Tokonami, Shinji

2008-08-01

In this paper, an account is given of the development, calibration and field use of a passive alpha track detector sensitive to thoron as well as to radon. No database of thoron and thoron progeny concentrations in dwellings in Ireland exists and, as a result, the level of exposure of the Irish population to thoron and its progeny is unknown. As an initial or pilot stage in establishing such a data base measurements of thoron and thoron progeny concentrations (the latter expressed in Equilibrium Equivalent Thoron Concentration (EETC)) were made in 40 randomly chosen Irish dwellings. The EETC measurements were made using a passive thoron progeny deposition rate monitor designed and supplied by NIRS (Japan). In addition standard unmodified SSI passive radon detectors were used to measure radon in these dwellings. The measured thoron concentrations ranged from below the level of detection to 154 Bq/m3 while the radon gas ranged from 15 to 179 Bq/m3. The thoron progeny EETC values for these dwellings ranged from 0.03 to 7.7 Bq/m3. An account is also given of the dosimetric implications of these measurements.

1989 Intercomparison of radon progeny measurement methods and equipment in North America

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

Scofield, P.; George, A.; Tu, Keng.

1990-03-01

At the 1989 {sup 222}Rn progeny intercomparison held at the Environmental Measurements Laboratory (EML), July 10--14, 1989, grab sampling and integrating/continuous {sup 222}Rn progeny methods were evaluated. Sixteen facilities participated in this intercomparison. Twelve facilities used {sup 222}Rn progeny grab sampling methods, and nine facilities used integrating/continuous instruments. Eighty-eight percent of the participants reported grab sample {sup 222}Rn progeny concentrations that were within 20% of the EML reference values. Good agreement between participant and EML grab-sample potential alpha energy concentrations (PAECs) was observed; 92% of the participants had PAECs within 20% of the EML values. For the integrating/continuous PAEC valuesmore » determined with integrating/continuous monitors, 89% of the participants were within 20% of the EML reference values. 9 refs., 3 figs., 4 tabs.« less

Progeny Clustering: A Method to Identify Biological Phenotypes

PubMed Central

Hu, Chenyue W.; Kornblau, Steven M.; Slater, John H.; Qutub, Amina A.

2015-01-01

Estimating the optimal number of clusters is a major challenge in applying cluster analysis to any type of dataset, especially to biomedical datasets, which are high-dimensional and complex. Here, we introduce an improved method, Progeny Clustering, which is stability-based and exceptionally efficient in computing, to find the ideal number of clusters. The algorithm employs a novel Progeny Sampling method to reconstruct cluster identity, a co-occurrence probability matrix to assess the clustering stability, and a set of reference datasets to overcome inherent biases in the algorithm and data space. Our method was shown successful and robust when applied to two synthetic datasets (datasets of two-dimensions and ten-dimensions containing eight dimensions of pure noise), two standard biological datasets (the Iris dataset and Rat CNS dataset) and two biological datasets (a cell phenotype dataset and an acute myeloid leukemia (AML) reverse phase protein array (RPPA) dataset). Progeny Clustering outperformed some popular clustering evaluation methods in the ten-dimensional synthetic dataset as well as in the cell phenotype dataset, and it was the only method that successfully discovered clinically meaningful patient groupings in the AML RPPA dataset. PMID:26267476

INADEQUACY OF THORON DOSE CALCULATIONS FROM THORON PROGENY MEASUREMENT ALONE.

PubMed

Lane-Smith, D; Wong, F K

2016-10-01

To determine the dose received by thoron ( 220 Rn) domestically, conventional methods measure the activity concentration of thoron progeny only (namely the 212 Pb atoms) and calculate the dose by using a set of conversion factors. This may be due to the measurement of progeny being simpler since it is longer lived and will be evenly spread throughout the room, whereas the thoron gas, with its short half-life, will exist only near the source and hence will not be of major concern for the majority of the room. However, concrete walls are a source of thoron, and spending prolonged amounts of time near them may lead to greatly increased radiation exposure, the degree of which is not revealed through progeny activity alone. The present paper compares the energy received from the ionising radiation of both thoron gas and thoron progeny near its source. Converting the energy dose to radiation dose is not within the scope of this paper. The results suggest a difference of an order of magnitude higher when taking into account the dose received by thoron gas. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

QTL analysis on rice grain appearance quality, as exemplifying the typical events of transgenic or backcrossing breeding

PubMed Central

Yan, Bao; Liu, Rongjia; Li, Yibo; Wang, Yan; Gao, Guanjun; Zhang, Qinglu; Liu, Xing; Jiang, Gonghao; He, Yuqing

2014-01-01

Rice grain shape and yield are usually controlled by multiple quantitative trait loci (QTL). This study used a set of F9–10 recombinant inbred lines (RILs) derived from a cross of Huahui 3 (Bt/Xa21) and Zhongguoxiangdao, and detected 27 QTLs on ten rice chromosomes. Among them, twelve QTLs responsive for grain shape/ or yield were mostly reproducibly detected and had not yet been reported before. Interestingly, the two known genes involved in the materials, with one insect-resistant Bt gene, and the other disease-resistant Xa21 gene, were found to closely link the QTLs responsive for grain shape and weight. The Bt fragment insertion was firstly mapped on the chromosome 10 in Huahui 3 and may disrupt grain-related QTLs resulting in weaker yield performance in transgenic plants. The introgression of Xa21 gene by backcrossing from donor material into receptor Minghui 63 may also contain a donor linkage drag which included minor-effect QTL alleles positively affecting grain shape and yield. The QTL analysis on rice grain appearance quality exemplified the typical events of transgenic or backcrossing breeding. The QTL findings in this study will in the future facilitate the gene isolation and breeding application for improvement of rice grain shape and yield. PMID:25320558

QTL analysis on rice grain appearance quality, as exemplifying the typical events of transgenic or backcrossing breeding.

PubMed

Yan, Bao; Liu, Rongjia; Li, Yibo; Wang, Yan; Gao, Guanjun; Zhang, Qinglu; Liu, Xing; Jiang, Gonghao; He, Yuqing

2014-09-01

Rice grain shape and yield are usually controlled by multiple quantitative trait loci (QTL). This study used a set of F9-10 recombinant inbred lines (RILs) derived from a cross of Huahui 3 (Bt/Xa21) and Zhongguoxiangdao, and detected 27 QTLs on ten rice chromosomes. Among them, twelve QTLs responsive for grain shape/ or yield were mostly reproducibly detected and had not yet been reported before. Interestingly, the two known genes involved in the materials, with one insect-resistant Bt gene, and the other disease-resistant Xa21 gene, were found to closely link the QTLs responsive for grain shape and weight. The Bt fragment insertion was firstly mapped on the chromosome 10 in Huahui 3 and may disrupt grain-related QTLs resulting in weaker yield performance in transgenic plants. The introgression of Xa21 gene by backcrossing from donor material into receptor Minghui 63 may also contain a donor linkage drag which included minor-effect QTL alleles positively affecting grain shape and yield. The QTL analysis on rice grain appearance quality exemplified the typical events of transgenic or backcrossing breeding. The QTL findings in this study will in the future facilitate the gene isolation and breeding application for improvement of rice grain shape and yield.

High time-resolved radon progeny measurements in the Arctic region (Svalbard islands, Norway): results and potentialities

NASA Astrophysics Data System (ADS)

Salzano, Roberto; Pasini, Antonello; Ianniello, Antonietta; Mazzola, Mauro; Traversi, Rita; Udisti, Roberto

2018-05-01

The estimation of radon progeny in the Arctic region represents a scientific challenge due to the required low limit of detection in consideration of the limited radon emanation associated with permafrost dynamics. This preliminary study highlighted, for the first time above 70° N, the possibility to monitor radon progeny in the Arctic region with a higher time resolution. The composition of the radon progeny offered the opportunity to identify air masses dominated by long-range transport, in presence or absence of near-constant radon progeny instead of long- and short-lived progenies. Furthermore, the different ratio between radon and thoron progenies evidenced the contributions of local emissions and atmospheric stability. Two different emanation periods were defined in accordance with the permafrost dynamics at the ground and several accumulation windows were recognized coherently to the meteo-climatic conditions occurring at the study site.

Deposition of radon progeny on skin surfaces and resulting radiation doses in radon therapy.

PubMed

Tempfer, H; Hofmann, W; Schober, A; Lettner, H; Dinu, A L

2010-05-01

In the Gastein valley, Austria, radon-rich thermal water and air have been used for decades for the treatment of various diseases. To explore the exposure pathway of radon progeny adsorbed to the skin, progeny activities on the skin of patients exposed to thermal water (in a bathtub) and hot vapour (in a vapour chamber) were measured by alpha spectrometry. Average total alpha activities on the patients' skin varied from 1.2 to 4.1 Bq/cm(2) in the bathtub, and from 1.1 to 2.6 Bq/cm(2) in the vapour bath. Water pH-value and ion concentration did affect radon progeny adsorption on the skin, whereas skin greasiness and blood circulation did not. Measurements of the penetration of deposited radon progeny into the skin revealed a roughly exponential activity distribution in the upper layers of the skin. Based on the radon progeny surface activity concentrations and their depth distributions, equivalent doses to different layers of the skin, in particular to the Langerhans cells located in the epidermis, ranged from 0.12 mSv in the thermal bath to 0.33 mSv in the vapour bath, exceeding equivalent doses to the inner organs (kidneys) by inhaled radon and progeny by about a factor 3, except for the lung, which receives the highest doses via inhalation. These results suggest that radon progeny attachment on skin surfaces may play a major role in the dosimetry for both thermal water and hot vapour treatment schemes.

Field Investigation of the Surface-deposited Radon Progeny as a Possible Predictor of the Airborne Radon Progeny Dose Rate

PubMed Central

Sun, Kainan; Steck, Daniel J.; Field, R. William

2009-01-01

The quantitative relationships between radon gas concentration, the surface-deposited activities of various radon progeny, the airborne radon progeny dose rate, and various residential environmental factors were investigated through actual field measurements in 38 selected Iowa houses occupied by either smokers or nonsmokers. Airborne dose rate was calculated from unattached and attached potential alpha energy concentrations (PAECs) using two dosimetric models with different activity-size weighting factors. These models are labeled Pdose and Jdose, respectively. Surface-deposited 218Po and 214Po were found significantly correlated to radon, unattached PAEC, and both airborne dose rates (p < 0.0001) in nonsmoking environments. However, deposited 218Po was not significantly correlated to the above parameters in smoking environments. In multiple linear regression analysis, natural logarithm transformation was performed for airborne dose rate as the dependent variable, as well as for radon and deposited 218Po and 214Po as predictors. An interaction effect was found between deposited 214Po and an obstacle in front of the Retrospective Reconstruction Detector (RRD) in predicting dose rate (p = 0.049 and 0.058 for Pdose and Jdose, respectively) for nonsmoking environments. After adjusting for radon and deposited radon progeny effects, the presence of either cooking, usage of a fireplace, or usage of a ceiling fan significantly, or marginal significantly, reduced the Pdose to 0.65 (90% CI 0.42–0.996), 0.54 (90% CI 0.28–1.02) and 0.66 (90% CI 0.45–0.96), respectively. For Jdose, only the usage of a ceiling fan significantly reduced the dose rate to 0.57 (90% CI 0.39–0.85). In smoking environments, deposited 218Po was a significant negative predictor for Pdose (RR 0.68, 90% CI 0.55–0.84) after adjusting for long-term 222Rn and environmental factors. A significant decrease of 0.72 (90% CI 0.64–0.83) in the mean Pdose was noted, after adjusting for the radon and

Linkage of loci associated with two pigment mutations on mouse chromosome 13.

PubMed

Holcombe, R F; Stephenson, D A; Zweidler, A; Stewart, R M; Chapman, V M; Seidman, J G

1991-08-01

Progeny from one intra- and two inter-specific backcrosses between divergent strains of mice were typed to map multiple markers in relation to two pigment mutations on mouse chromosome 13, beige (bg) and pearl (pe). Both recessive mutants on a C57BL/6J background were crossed separately with laboratory strain PAC (M. domesticus) and the partially inbred M. musculus stock PWK. The intra- and inter-specific F1 hybrids were backcrossed to the C57BL/6J parental strain and DNA was prepared from progeny. Restriction fragment length polymorphisms were used to follow the segregation of alleles in the backcross offspring at loci identified with molecular probes. The linkage analysis defines the association between the bg and pe loci and the loci for the T-cell receptor gamma-chain gene (Tcrg), the spermatocyte specific histone gene (Hist1), the prolactin gene (Prl), the Friend murine leukaemia virus integration site 1 (Fim-1), the murine Hanukuh Factor gene (Muhf/Ctla-3) and the dihydrofolate reductase gene (Dhfr). This data confirms results of prior chromosomal mapping studies utilizing bg as an anchor locus, and provides previously unreported information defining the localization of the prolactin gene on mouse chromosome 13. The relationship of multiple loci in relation to pe is similarly defined. These results may help facilitate localization of the genes responsible for two human syndromes homologous with bg and pe, Chediak-Higashi syndrome and Hermansky-Pudlak syndrome.

Genetic potential of common bean progenies obtained by different breeding methods evaluated in various environments.

PubMed

Pontes Júnior, V A; Melo, P G S; Pereira, H S; Melo, L C

2016-09-02

Grain yield is strongly influenced by the environment, has polygenic and complex inheritance, and is a key trait in the selection and recommendation of cultivars. Breeding programs should efficiently explore the genetic variability resulting from crosses by selecting the most appropriate method for breeding in segregating populations. The goal of this study was to evaluate and compare the genetic potential of common bean progenies of carioca grain for grain yield, obtained by different breeding methods and evaluated in different environments. Progenies originating from crosses between lines and CNFC 7812 and CNFC 7829 were replanted up to the F 7 generation using three breeding methods in segregating populations: population (bulk), bulk within F 2 progenies, and single-seed descent (SSD). Fifteen F 8 progenies per method, two controls (BRS Estilo and Perola), and the parents were evaluated in a 7 x 7 simple lattice design, with plots of two 4-m rows. The tests were conducted in 10 environments in four States of Brazil and in three growing seasons in 2009 and 2010. Genetic parameters including genetic variance, heritability, variance of interaction, and expected selection gain were estimated. Genetic variability among progenies and the effect of progeny-environment interactions were determined for the three methods. The breeding methods differed significantly due to the effects of sampling procedures on the progenies and due to natural selection, which mainly affected the bulk method. The SSD and bulk methods provided populations with better estimates of genetic parameters and more stable progenies that were less affected by interaction with the environment.

Selection of inbred maize (Zea mays L.) progenies by topcrosses conducted in contrasting environments.

PubMed

Rodrigues, C S; Pacheco, C A P; Guedes, M L; Pinho, R G V; Castro, C R

2016-09-23

The aim of this study was to identify inbred progenies of S 0:1 maize (Zea mays L.) plants that were efficient at a low level of technology and responsive at a high level of technology through the use of topcrosses. Two contrasting environments were created using two levels of base fertilization and topdressing, so that the levels of nitrogen, phosphorus, and potassium were applied four times higher in one environment than in the other. We used S 0:1 progenies derived from commercial hybrids in topcrosses with two testers (an elite line from the flint heterotic group and an elite line from the dent heterotic group). The progenies and three controls were evaluated in an augmented block design in Nossa Senhora das Dores, SE, Brazil in the 2010 crop season. The average grain yield in the high-technological level was 21.44% greater than that in the low-technological level. There were no changes in progeny behavior in the two technological levels for grain yield. The testers did not differ in the average grain yield of the progenies at the two technological levels. Therefore, it is possible to select progenies derived from commercial hybrids that have an efficient response to fertilization.

Construction and Comparative Analyses of Highly Dense Linkage Maps of Two Sweet Cherry Intra-Specific Progenies of Commercial Cultivars

PubMed Central

Quero-García, José; Guzmán, Alejandra; Mansur, Levi; Gratacós, Eduardo; Silva, Herman; Rosyara, Umesh R.; Iezzoni, Amy; Meisel, Lee A.; Dirlewanger, Elisabeth

2013-01-01

Despite the agronomical importance and high synteny with other Prunus species, breeding improvements for cherry have been slow compared to other temperate fruits, such as apple or peach. However, the recent release of the peach genome v1.0 by the International Peach Genome Initiative and the sequencing of cherry accessions to identify Single Nucleotide Polymorphisms (SNPs) provide an excellent basis for the advancement of cherry genetic and genomic studies. The availability of dense genetic linkage maps in phenotyped segregating progenies would be a valuable tool for breeders and geneticists. Using two sweet cherry (Prunus avium L.) intra-specific progenies derived from crosses between ‘Black Tartarian’ × ‘Kordia’ (BT×K) and ‘Regina’ × ‘Lapins’(R×L), high-density genetic maps of the four parental lines and the two segregating populations were constructed. For BT×K and R×L, 89 and 121 F1 plants were used for linkage mapping, respectively. A total of 5,696 SNP markers were tested in each progeny. As a result of these analyses, 723 and 687 markers were mapped into eight linkage groups (LGs) in BT×K and R×L, respectively. The resulting maps spanned 752.9 and 639.9 cM with an average distance of 1.1 and 0.9 cM between adjacent markers in BT×K and R×L, respectively. The maps displayed high synteny and co-linearity between each other, with the Prunus bin map, and with the peach genome v1.0 for all eight LGs (LG1–LG8). These maps provide a useful tool for investigating traits of interest in sweet cherry and represent a qualitative advance in the understanding of the cherry genome and its synteny with other members of the Rosaceae family. PMID:23382953

Progeny from dedifferentiated adipocytes display protracted adipogenesis

USDA-ARS?s Scientific Manuscript database

Progeny of adipofibroblast cells, derived from mature bovine adipocytes, were used to determine their ability to redifferentiate into lipid-assimilating adipocytes. Traditional cell biology methods were used, including the expression of adipogenic markers such as PPAR'. When exposed to medium supple...

High Correlated Paternity Leads to Negative Effects on Progeny Performance in Two Mediterranean Shrub Species.

PubMed

Nora, Sofia; Aparicio, Abelardo; Albaladejo, Rafael G

2016-01-01

Anthropogenic habitat deterioration can promote changes in plant mating systems that subsequently may affect progeny performance, thereby conditioning plant recruitment for the next generation. However, very few studies yet tested mating system parameters other than outcrossing rates; and the direct effects of the genetic diversity of the pollen received by maternal plants (i.e. correlated paternity) has often been overlooked. In this study, we investigated the relation between correlated paternity and progeny performance in two common Mediterranean shrubs, Myrtus communis and Pistacia lentiscus. To do so, we collected open-pollinated progeny from selected maternal plants, calculated mating system parameters using microsatellite genotyping and conducted sowing experiments under greenhouse and field conditions. Our results showed that some progeny fitness components were negatively affected by the high correlated paternity of maternal plants. In Myrtus communis, high correlated paternity had a negative effect on the proportion and timing of seedling emergence in the natural field conditions and in the greenhouse sowing experiment, respectively. In Pistacia lentiscus, seedling emergence time under field conditions was also negatively influenced by high correlated paternity and a progeny survival analysis in the field experiment showed greater mortality of seedlings from maternal plants with high correlated paternity. Overall, we found effects of correlated paternity on the progeny performance of Myrtus communis, a self-compatible species. Further, we also detected effects of correlated paternity on the progeny emergence time and survival in Pistacia lentiscus, an obligate outcrossed species. This study represents one of the few existing empirical examples which highlight the influence that correlated paternity may exert on progeny performance in multiple stages during early seedling growth.

High Correlated Paternity Leads to Negative Effects on Progeny Performance in Two Mediterranean Shrub Species

PubMed Central

Nora, Sofia; Aparicio, Abelardo; Albaladejo, Rafael G.

2016-01-01

Anthropogenic habitat deterioration can promote changes in plant mating systems that subsequently may affect progeny performance, thereby conditioning plant recruitment for the next generation. However, very few studies yet tested mating system parameters other than outcrossing rates; and the direct effects of the genetic diversity of the pollen received by maternal plants (i.e. correlated paternity) has often been overlooked. In this study, we investigated the relation between correlated paternity and progeny performance in two common Mediterranean shrubs, Myrtus communis and Pistacia lentiscus. To do so, we collected open-pollinated progeny from selected maternal plants, calculated mating system parameters using microsatellite genotyping and conducted sowing experiments under greenhouse and field conditions. Our results showed that some progeny fitness components were negatively affected by the high correlated paternity of maternal plants. In Myrtus communis, high correlated paternity had a negative effect on the proportion and timing of seedling emergence in the natural field conditions and in the greenhouse sowing experiment, respectively. In Pistacia lentiscus, seedling emergence time under field conditions was also negatively influenced by high correlated paternity and a progeny survival analysis in the field experiment showed greater mortality of seedlings from maternal plants with high correlated paternity. Overall, we found effects of correlated paternity on the progeny performance of Myrtus communis, a self-compatible species. Further, we also detected effects of correlated paternity on the progeny emergence time and survival in Pistacia lentiscus, an obligate outcrossed species. This study represents one of the few existing empirical examples which highlight the influence that correlated paternity may exert on progeny performance in multiple stages during early seedling growth. PMID:27835658

Development of an aerosol chamber for calibration of 220Rn progeny detectors

NASA Astrophysics Data System (ADS)

Sorimachi, Atsuyuki; Ishikawa, Tetsuo; Tokonami, Shinji

2014-09-01

This paper describes an aerosol chamber system that can be used for calibrations and performance experiments of passive 220Rn progeny detectors. For the purpose of this study, an aerosol generation system using carnauba wax as the aerosol material was mounted into the 220Rn chamber. We used the chamber to measure characteristics of the equilibrium factor (F) of 220Rn and unattached fraction (fp) of 220Rn progeny, which are important parameters for dose estimation. The first experiment showed that continuous and stable generation of the unattached and aerosol-attached 220Rn progeny concentrations was obtained. We observed that the spatial distributions in the chamber of the vertical profiles of the unattached and aerosol-attached 220Rn progeny concentrations were homogeneous, as were the particle number concentration and count median diameter. The values of F and fp and their characteristics observed in this study were in the same range as the values reported from indoor measurements. We found that the characteristics of F and fp were dependent on the aerosol conditions (particle diameter and particle number concentration).

Genetic and Biochemical Characterization of Monokaryotic Progeny Strains of Button Mushroom (Agaricus bisporus)

PubMed Central

Kwon, Hyuk Woo; Choi, Min Ah; Yun, Yeo Hong; Oh, Youn-Lee; Kong, Won-Sik

2015-01-01

To promote the selection of promising monokaryotic strains of button mushroom (Agaricus bisporus) during breeding, 61 progeny strains derived from basidiospores of two different lines of dikaryotic parental strains, ASI1038 and ASI1346, were analyzed by nucleotide sequencing of the intergenic spacer I (IGS I) region in their rDNA and by extracellular enzyme assays. Nineteen different sizes of IGS I, which ranged from 1,301 to 1,348 bp, were present among twenty ASI1346-derived progeny strains, while 15 different sizes of IGS I, which ranged from 700 to 1,347 bp, were present among twenty ASI1038-derived progeny strains. Phylogenetic analysis of the IGS sequences revealed that different clades were present in both the ASI10388- and ASI1346-derived progeny strains. Plating assays of seven kinds of extracellular enzymes (β-glucosidase, avicelase, CM-cellulase, amylase, pectinase, xylanase, and protease) also revealed apparent variation in the ability to produce extracellular enzymes among the 40 tested progeny strains from both parental A. bisporus strains. Overall, this study demonstrates that characterization of IGS I regions and extracellular enzymes is useful for the assessment of the substrate-degrading ability and heterogenicity of A. bisporus monokaryotic strains. PMID:25892920

INDOOR RADON, THORON AND THEIR PROGENY CONCENTRATIONS IN HIGH THORON RURAL SERBIA ENVIRONMENTS.

PubMed

Zunic, Zora S; Stojanovska, Z; Veselinovic, N; Mishra, R; Yarmoshenko, I V; Sapra, B K; Ishikawa, T; Omori, Y; Curguz, Z; Bossew, P; Udovicic, V; Ramola, R C

2017-11-01

This article deals with the variation of radon (Rn), thoron (Tn) and their progeny concentrations expressed in terms of equilibrium equivalent concentrations (EERC and EETC), in 40 houses, in four villages of Sokobanja municipality, Southern Serbia. Two types of passive detectors were used: (1) discriminative radon-thoron detector for simultaneous Rn and Tn gases measurements and (2) direct Tn and Rn progeny sensors (DRPS/DTPS) for measuring Rn and Tn progeny concentrations. Detectors were exposed simultaneously for a single period of 12 months. Variations of Tn and EETC appear higher than those of Rn and EERC. Analysis of the spatial variation of the measured concentrations is also reported. This work is part of a wider survey of Rn, Tn and their progeny concentrations in indoor environments throughout the Balkan region started in 2011 year. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Aubergine Controls Germline Stem Cell Self-Renewal and Progeny Differentiation via Distinct Mechanisms.

PubMed

Ma, Xing; Zhu, Xiujuan; Han, Yingying; Story, Benjamin; Do, Trieu; Song, Xiaoqing; Wang, Su; Zhang, Ying; Blanchette, Marco; Gogol, Madelaine; Hall, Kate; Peak, Allison; Anoja, Perera; Xie, Ting

2017-04-24

Piwi family protein Aubergine (Aub) maintains genome integrity in late germ cells of the Drosophila ovary through Piwi-associated RNA-mediated repression of transposon activities. Although it is highly expressed in germline stem cells (GSCs) and early progeny, it remains unclear whether it plays any roles in early GSC lineage development. Here we report that Aub promotes GSC self-renewal and GSC progeny differentiation. RNA-iCLIP results show that Aub binds the mRNAs encoding self-renewal and differentiation factors in cultured GSCs. Aub controls GSC self-renewal by preventing DNA-damage-induced Chk2 activation and by translationally controlling the expression of self-renewal factors. It promotes GSC progeny differentiation by translationally controlling the expression of differentiation factors, including Bam. Therefore, this study reveals a function of Aub in GSCs and their progeny, which promotes translation of self-renewal and differentiation factors by directly binding to its target mRNAs and interacting with translational initiation factors. Copyright © 2017 Elsevier Inc. All rights reserved.

Growth, reproductive performance, carcass characteristics and meat quality in F1 and F2 progenies of somatic cell-cloned pigs.

PubMed

Adachi, Noritaka; Yamaguchi, Daisuke; Watanabe, Akiyuki; Miura, Narumi; Sunaga, Seiji; Oishi, Hitoshi; Hashimoto, Michiko; Oishi, Takatsugu; Iwamoto, Masaki; Hanada, Hirofumi; Kubo, Masanori; Onishi, Akira

2014-04-24

The objective of this study was to examine the health and meat production of cloned sows and their progenies in order to demonstrate the application of somatic cell cloning to the pig industry. This study compared the growth, reproductive performance, carcass characteristics and meat quality of Landrace cloned sows, F1 progenies and F2 progenies. We measured their body weight, growth rate and feed conversion and performed a pathological analysis of their anatomy to detect abnormalities. Three of the five cloned pigs were used for a growth test. Cloned pigs grew normally and had characteristics similar to those of the control purebred Landrace pigs. Two cloned gilts were bred with a Landrace boar and used for a progeny test. F1 progenies had characteristics similar to those of the controls. Two of the F1 progeny gilts were bred with a Duroc or Large White boar and used for the progeny test. F2 progenies grew normally. There were no biological differences in growth, carcass characteristics and amino acid composition among cloned sows, F1 progenies, F2 progenies and conventional pigs. The cloned sows and F1 progenies showed normal reproductive performance. No specific abnormalities were observed by pathological analysis, with the exception of periarteritis in the F1 progenies. All pigs had a normal karyotype. These results demonstrate that cloned female pigs and their progenies have similar growth, reproductive performance and carcass quality characteristics and that somatic cell cloning could be a useful technique for conserving superior pig breeds in conventional meat production.

Growth, Reproductive Performance, Carcass Characteristics and Meat Quality in F1 and F2 Progenies of Somatic Cell-Cloned Pigs

PubMed Central

ADACHI, Noritaka; YAMAGUCHI, Daisuke; WATANABE, Akiyuki; MIURA, Narumi; SUNAGA, Seiji; OISHI, Hitoshi; HASHIMOTO, Michiko; OISHI, Takatsugu; IWAMOTO, Masaki; HANADA, Hirofumi; KUBO, Masanori; ONISHI, Akira

2014-01-01

The objective of this study was to examine the health and meat production of cloned sows and their progenies in order to demonstrate the application of somatic cell cloning to the pig industry. This study compared the growth, reproductive performance, carcass characteristics and meat quality of Landrace cloned sows, F1 progenies and F2 progenies. We measured their body weight, growth rate and feed conversion and performed a pathological analysis of their anatomy to detect abnormalities. Three of the five cloned pigs were used for a growth test. Cloned pigs grew normally and had characteristics similar to those of the control purebred Landrace pigs. Two cloned gilts were bred with a Landrace boar and used for a progeny test. F1 progenies had characteristics similar to those of the controls. Two of the F1 progeny gilts were bred with a Duroc or Large White boar and used for the progeny test. F2 progenies grew normally. There were no biological differences in growth, carcass characteristics and amino acid composition among cloned sows, F1 progenies, F2 progenies and conventional pigs. The cloned sows and F1 progenies showed normal reproductive performance. No specific abnormalities were observed by pathological analysis, with the exception of periarteritis in the F1 progenies. All pigs had a normal karyotype. These results demonstrate that cloned female pigs and their progenies have similar growth, reproductive performance and carcass quality characteristics and that somatic cell cloning could be a useful technique for conserving superior pig breeds in conventional meat production. PMID:24492641

Identification of quantitative trait loci affecting resistance to gastro-intestinal parasites in a double backcross population of Red Maasai and Dorper sheep

USDA-ARS?s Scientific Manuscript database

A genome-wide scan for quantitative trait loci (QTL) affecting gastrointestinal (GI) nematode resistance was completed using a double backcross sheep population derived from Red Maasai and Dorper ewes bred to F1 rams. These breeds were chosen, because Red Maasai sheep are known to be more tolerant ...

Inhalation dose due to radon, thoron, and progenies in dwellings of a hill station.

PubMed

Sivakumar, R

2017-02-01

The general public spends a major portion of their time in an indoor environment and hence receives a considerable amount of radiation. Knowledge about indoor radiation is important in order to arrive at the actual effective dose received by residents. The indoor radon, thoron, and progeny concentrations observed in the present study were found to vary with seasons of a given year. The highest and lowest indoor average radon, thoron, and progeny levels were observed during winter and summer seasons, respectively. The concentrations of indoor radon, thoron, and progenies were found to vary with the type of houses. The highest 222 Rn, 220 Rn, and progeny concentrations were observed in mud houses and the lowest values were recorded in wooden houses. The indoor 222 Rn concentration correlated well with concentration of its grandparent 238 U in underlying soil with a correlation coefficient of 0.87. The correlation between indoor 220 Rn and 232 Th in the underlying soil was found to be 0.64. The estimated effective doses received by the general public in the present study due to indoor radon and thoron were 1.49 ± 0.49 and 1.30 ± 0.53 mSv/year, respectively. The annual effective doses due to radon and thoron progenies were estimated as 0.76 ± 0.27 and 0.47 ± 0.23 mSv/year, respectively. The contributions from 222 Rn, 220 Rn, and corresponding progenies to the annual effective doses received were 37, 32, 19, and 12%, respectively. The general public living in the study area receives an inhalation dose of 4.02 mSv/year due to indoor radon, thoron, and progenies, which were found to be less than the action limit of ICRP 2009.

Genetic Dissection of Clonally Inherited Genomes of Poeciliopsis. I. Linkage Analysis and Preliminary Assessment of Deleterious Gene Loads

PubMed Central

Leslie, James F.; Vrijenhoek, Robert C.

1978-01-01

Theoretical considerations suggest that a high load of deleterious mutations should accumulate in asexual genomes. An ideal system for testing this hypothesis occurs in the hybrid all-female fish Poeciliopsis monacha-lucida. The hybrid genotype is retained between generations by an oogenetic process that transmits only a nonrecombinant haploid monacha genome to their ova. The hybrid genotype is re-established in nature by fertilization of these monacha eggs with sperm from a sexual species, P. lucida. The unique reproductive mechanism of these hybrids allows the genetic dissection of the clonal monacha genome by forced matings with males of P. monacha. The resultant F1 hybrids and their backcross progeny were examined to determine the amount and kinds of genetic changes that might have occurred in two clonal monacha genomes.—Using six allozyme markers, four similar linkage groups were identified in each clonal genome. Segregation and assortment at these loci revealed no apparent differences between monacha genomes from sexually and clonally reproducing species. Mortality of F1 and backcross progeny revealed differences between the two clonal genomes, suggesting that deleterious genes may accumulate in genomes sheltered from recombination. PMID:17248875

Time dependence of 222Rn, 220Rn and their progenies' distributions in a diffusion chamber

NASA Astrophysics Data System (ADS)

Stevanovic, N.; Markovic, V. M.; Nikezic, D.

2017-11-01

Diffusion chamber with SSNTD (Solid State Nuclear Track Detector) placed inside is a passive detector for measuring the activity of 222Rn and 220Rn (radon and thoron) and their progenies. Calibration from detected alpha particle tracks to progeny activity is often acquired from theoretical models. One common assumption related to these models found in literature is that concentrations of 222Rn and 220Rn at the entrance of a chamber are constant during the exposure. In this paper, concentrations of 222Rn and 220Rn at the entrance of the chamber are taken to be variable with time, which is actually the case in reality. Therefore, spatial distributions of 222Rn and 220Rn and their progenies inside the diffusion chamber should be time dependent. Variation of 222Rn and 220Rn concentrations on the entrance of the chamber was modeled on the basis of true measurements. Diffusion equations in cylindrical coordinates were solved using FDM (Finite Difference Method) to obtain spatial distributions as functions of time. It was shown that concentrations of 222Rn, 220Rn and their progenies were not homogeneously distributed in the chamber. Due to variable 222Rn and 220Rn concentrations at the entrance of the chamber, steady state (the case when concentration of 222Rn, 220Rn and their progenies inside the chamber remains unchanged with time) could not be reached. Deposition of progenies on the chamber walls was considered and it was shown that distributions of deposited progenies were not uniform over walls' surface.

Limited Fitness Advantages of Crop-Weed Hybrid Progeny Containing Insect-Resistant Transgenes (Bt/CpTI) in Transgenic Rice Field

PubMed Central

Yang, Xiao; Wang, Feng; Su, Jun; Lu, Bao-Rong

2012-01-01

Background The spread of insect-resistance transgenes from genetically engineered (GE) rice to its coexisting weedy rice (O. sativa f. spontanea) populations via gene flow creates a major concern for commercial GE rice cultivation. Transgene flow to weedy rice seems unavoidable. Therefore, characterization of potential fitness effect brought by the transgenes is essential to assess environmental consequences caused by crop-weed transgene flow. Methodology/Principal Findings Field performance of fitness-related traits was assessed in advanced hybrid progeny of F4 generation derived from a cross between an insect-resistant transgenic (Bt/CpTI) rice line and a weedy strain. The performance of transgene-positive hybrid progeny was compared with the transgene-negative progeny and weedy parent in pure and mixed planting of transgenic and nontransgenic plants under environmental conditions with natural vs. low insect pressure. Results showed that under natural insect pressure the insect-resistant transgenes could effectively suppress target insects and bring significantly increased fitness to transgenic plants in pure planting, compared with nontransgenic plants (including weedy parent). In contrast, no significant differences in fitness were detected under low insect pressure. However, such increase in fitness was not detected in the mixed planting of transgenic and nontransgenic plants due to significantly reduced insect pressure. Conclusions/Significance Insect-resistance transgenes may have limited fitness advantages to hybrid progeny resulted from crop-weed transgene flow owning to the significantly reduced ambient target insect pressure when an insect-resistant GE crop is grown. Given that the extensive cultivation of an insect-resistant GE crop will ultimately reduce the target insect pressure, the rapid spread of insect-resistance transgenes in weedy populations in commercial GE crop fields may be not likely to happen. PMID:22815975

Effects of temporal dynamics, nut weight and nut size on growth of American chestnut, Chinese chestnut and backcross generations in a commercial nursery

Treesearch

Cornelia Pinchot; Stacy Clark; Scott Schlarbaum; Arnold Saxton; Shi-Jean Sung; Frederick. Hebard

2015-01-01

Blight-resistant American chestnut (Castanea dentata) may soon be commercially available, but few studies have tested methods to produce high quality seedlings that will be competitive after planting. This study evaluated the performance of one American, one Chinese (C. mollissima), one second-generation backcross (BC3...

The influence of environmental factors on the deposition velocity of thoron progeny.

PubMed

Li, H; Zhang, L; Guo, Q

2012-11-01

Passive measuring devices are comprehensively employed in thoron progeny surveys, while the deposition velocity of thoron progeny is the most critical parameter, which varies in different environments. In this study, to analyse the influence of environmental factors on thoron progeny deposition velocity, an improved model was proposed on the basis of Lai's aerosol deposition model and the Jacobi's model, and a series of measurements were carried out to verify the model. According to the calculations, deposition velocity decreases with increasing aerosol diameter and also aerosol concentration, while increases with increasing ventilation rate. In typical indoor environments, a typical value of 1.26 × 10(-5)m s(-1) is recommended, with a range between 7.6 × 10(-7) and 3.2 × 10(-4) m s(-1).

Cypress surrogate mother produces haploid progeny from alien pollen.

PubMed

Pichot, Christian; Liens, Benjamin; Nava, Juana L Rivera; Bachelier, Julien B; El Maâtaoui, Mohamed

2008-01-01

Although most living organisms reproduce sexually, some have developed a uniparental reproduction where the embryo usually derives from the female parent. A unique case of paternal apomixis in plants has been recently reported in Cupressus dupreziana, an endangered Mediterranean conifer. This species produces unreduced pollen that develop into all-paternal embryos within the seed tissues. We analyzed seedlings produced by open-pollinated C. dupreziana seed trees using morphological descriptors, ploidy levels assessed through flow cytometry, and AFLP genetic diversity. In situ C. dupreziana seed trees (from Algeria) produced only diploid C. dupreziana progeny. In contrast, only one-third of the progeny produced by ex situ C. dupreziana seed trees planted in French collections were similar to C. dupreziana seedlings; the other progeny were haploid or diploid C. sempervirens seedlings. These results demonstrate that C. dupreziana ovules allow for the development of all-paternal embryos from pollen produced by another species, C. sempervirens. Thus, the in planta androgenesis is achieved through the combination of the embryogenic behavior of pollen grains and the ability of seed tree ovules to act as a surrogate mother. This phenomenon offers a unique opportunity to produce, by natural means, highly valuable material for genetic studies and selection of sterile cultivars.

Systemic functional expression of N-acetyltransferase polymorphism in the F344 Nat2 congenic rat

PubMed Central

Hein, David W.; Bendaly, Jean; Neale, Jason R.; Doll, Mark A.

2008-01-01

Rat lines congenic for the rat N-acetyltransferase 2 [(RAT)Nat2] gene were constructed and characterized. F344 (homozygous Nat2 rapid) males were mated to WKY (homozygous Nat2 slow) females to produce heterozygous F1. F1 females were then backcrossed to F344 males. Heterozygous acetylator female progeny from this and each successive backcross were identified by rat Nat2 genotyping and mated with F344 rapid acetylator males. Following ten generations of backcross mating, heterozygous acetylator brother/sister progeny were mated to produce the homozgygous rapid and slow acetylator Nat2 congenic rat lines. p-Aminobenzoic acid (selective for rat NAT2) and 4-aminobiphenyl N-acetyltransferase activities were expressed in all tissues examined (liver, lung, esophagus, stomach, small intestine, colon, pancreas, kidney, skin, leukocytes, and urinary bladder in male and female rats and in breast of female and prostate of male rats). NAT2 expression in rat extrahepatic tissues was much higher than in liver. In each tissue, activities were Nat2-genotype dependent, with highest levels in homozygous rapid acetylators, intermediate levels in heterozygous acetylators, and lowest in homozygous slow acetylators. Sulfamethazine (selective for rat NAT1) N-acetyltransferase activities were observed in all tissues examined in both male and female rats except for breast (females), bladder and leukocytes. In each tissue, the activity was Nat2-genotype independent, with similar levels in homozygous rapid, heterozygous, and homozygous slow acetylators. These congenic rat lines are useful to investigate the role of NAT2 genetic polymorphism in susceptibility to cancers related to arylamine carcinogen exposures. PMID:18799801

Identification of novel genes significantly affecting growth in catfish through GWAS analysis.

PubMed

Li, Ning; Zhou, Tao; Geng, Xin; Jin, Yulin; Wang, Xiaozhu; Liu, Shikai; Xu, Xiaoyan; Gao, Dongya; Li, Qi; Liu, Zhanjiang

2018-06-01

Growth is the most important economic trait in aquaculture. Improvements in growth-related traits can enhance production, reduce costs and time to produce market-size fish. Catfish is the major aquaculture species in the United States, accounting for 65% of the US finfish production. However, the genes underlying growth traits in catfish were not well studied. Currently, the majority of the US catfish industry uses hybrid catfish derived from channel catfish female mated with blue catfish male. Interestingly, channel catfish and blue catfish exhibit differences in growth-related traits, and therefore the backcross progenies provide an efficient system for QTL analysis. In this study, we conducted a genome-wide association study for catfish body weight using the 250 K SNP array with 556 backcross progenies generated from backcross of male F1 hybrid (female channel catfish × male blue catfish) with female channel catfish. A genomic region of approximately 1 Mb on linkage group 5 was found to be significantly associated with body weight. In addition, four suggestively associated QTL regions were identified on linkage groups 1, 2, 23 and 24. Most candidate genes in the associated regions are known to be involved in muscle growth and bone development, some of which were reported to be associated with obesity in humans and pigs, suggesting that the functions of these genes may be evolutionarily conserved in controlling growth. Additional fine mapping or functional studies should allow identification of the causal genes for fast growth in catfish, and elucidation of molecular mechanisms of regulation of growth in fish.

Characterization of early follicular cDNA library suggests evidence for genetic polymorphisms in the inbred strain C108 of Bombyx mori.

PubMed

Mills, D R; Goldsmith, M R

2000-04-01

Recent work towards the completion of a saturated molecular genetic linkage map for the lepidopteran silkworm, Bombyx mori (n = 28), has provided evidence for existing polymorphisms in the inbred strain C108. Two inbred parental strains, p50 and C108, were crossed to produce the F1 (P/C) hybrid offspring. The populations used in this project were comprised of a combination of 29 F2 (F1 x F1) and 31 reciprocal backcross (P/C x C/C, P/C x P/P) progeny. All restriction fragment length polymorphisms (RFLPs) for the initial analysis were hybridized with anonymous probes derived from a random early follicular cDNA (Rcf) library from Bombyx. A total of 19 Rcf probes were selected as showing scorable codominant polymorphic patterns when screened against F2 and backcross DNAs digested with the restriction enzymes EcoRI, HindIII, or PstI, and Southern blotted to nylon membranes for hybridization. Of the newly reported Rcf probes, 7 (37%) were characterized as producing 'simple' polymorphic patterns, while 12 (63%) were characterized as producing 'complex' polymorphic patterns. Further characterization of the complex patterns subdivided this group into two general classes: polymorphisms that contained an additional allele, and multiple bands that contained an easily scored two banded polymorphism. Because the extra allele class was limited to the (P/C x C/C) backcross progeny, it is suggested that the inbred parental strain C108 harbors polymorphic loci that are inherited in a simple Mendelian fashion. A genetic analysis discussing plausible origins and maintenance of these polymorphisms is presented.

Intercomparison of active and passive instruments for radon and radon progeny in North America

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

George, A.C.; Tu, Keng-Wu; Knutson, E.O.

1995-02-01

An intercomparison exercise for radon and radon progeny instruments and methods was held at the Environmental Measurements Laboratory (EML) from April 22--May 2, 1994. The exercise was conducted in the new EML radon test and calibration facility in which conditions of exposure are very well controlled. The detection systems of the intercompared instruments consisted of. (1) pulse ionization chambers, (2) electret ionization chambers, (3) scintillation detectors, (4) alpha particle spectrometers with silicon diodes, surface barrier or diffused junction detectors, (5) registration of nuclear tracks in solid-state materials, and (6) activated carbon collectors counted by gamma-ray spectrometry or by alpha- andmore » beta-liquid scintillation counting. 23 private firms, government laboratories and universities participated with a 165 passive integrating devices consisting of: Activated carbon collectors, nuclear alpha track detectors and electret ionization chambers, and 11 active and passive continuous radon monitors. Five portable integrating and continuous instruments were intercompared for radon progeny. Forty grab samples for radon progeny were taken by five groups that participated in person to test and evaluate their primary instruments and methods that measure individual radon progeny and the potential alpha energy concentration (PAEC) in indoor air. Results indicate that more than 80% of the measurements for radon performed with a variety of instruments, are within {plus_minus}10% of actual value. The majority of the instruments that measure individual radon progeny and the PAEC gave results that are in good agreement with the EML reference value. Radon progeny measurements made with continuous and integrating instruments are satisfactory with room for improvement.« less

Genetic control of the honey bee (Apis mellifera) dance language: segregating dance forms in a backcrossed colony.

PubMed

Johnson, R N; Oldroyd, B P; Barron, A B; Crozier, R H

2002-01-01

We studied the genetic control of the dance dialects that exist in the different subspecies of honey bees (Apis mellifera) by observing the variation in dance form observed in a backcross between two lines that showed widely different dance dialects. To do this we generated the reciprocal of the cross performed by Rinderer and Beaman (1995), thus producing phenotypic segregation of dance forms within a single colony rather than between colonies. Our results are consistent with Rinderer and Beaman (1995) in that inheritance of the transition point from round dancing --> waggle dancing is consistent with control by a single locus with more than one allele. That is, we found one dance type to be dominant in the F(1), and observed a 1:1 segregation of dance in a backcross involving the F(1) and the recessive parent. However, we found some minor differences in dance dialect inheritance, with the most significant being an apparent reversal of dominance between our cross (for us "black" is the dominant dialect) and that of Rinderer and Beaman (1995) (they report "yellow" to be the dominant dialect). We also found that our black bees do not perform a distinct sickle dance, whereas the black bees used by Rinderer and Beaman (1995) did perform such a dance. However, our difference in dominance need not contradict the results of Rinderer and Beaman (1995), as there is no evidence that body color and dominance for dance dialect are linked.

Polyploid titan cells produce haploid and aneuploid progeny to promote stress adaptation.

PubMed

Gerstein, Aleeza C; Fu, Man Shun; Mukaremera, Liliane; Li, Zhongming; Ormerod, Kate L; Fraser, James A; Berman, Judith; Nielsen, Kirsten

2015-10-13

Cryptococcus neoformans is a major life-threatening fungal pathogen. In response to the stress of the host environment, C. neoformans produces large polyploid titan cells. Titan cell production enhances the virulence of C. neoformans, yet whether the polyploid aspect of titan cells is specifically influential remains unknown. We show that titan cells were more likely to survive and produce offspring under multiple stress conditions than typical cells and that even their normally sized daughters maintained an advantage over typical cells in continued exposure to stress. Although polyploid titan cells generated haploid daughter cell progeny upon in vitro replication under nutrient-replete conditions, titan cells treated with the antifungal drug fluconazole produced fluconazole-resistant diploid and aneuploid daughter cells. Interestingly, a single titan mother cell was capable of generating multiple types of aneuploid daughter cells. The increased survival and genomic diversity of titan cell progeny promote rapid adaptation to new or high-stress conditions. The ability to adapt to stress is a key element for survival of pathogenic microbes in the host and thus plays an important role in pathogenesis. Here we investigated the predominantly haploid human fungal pathogen Cryptococcus neoformans, which is capable of ploidy and cell size increases during infection through production of titan cells. The enlarged polyploid titan cells are then able to rapidly undergo ploidy reduction to generate progeny with reduced ploidy and/or aneuploidy. Under stressful conditions, titan cell progeny have a growth and survival advantage over typical cell progeny. Understanding how titan cells enhance the rate of cryptococcal adaptation under stress conditions may assist in the development of novel drugs aimed at blocking ploidy transitions. Copyright © 2015 Gerstein et al.

MEASUREMENT OF RADON, THORON AND THEIR PROGENY CONCENTRATIONS IN THE DWELLINGS OF PAURI GARHWAL, UTTARAKHAND, INDIA.

PubMed

Joshi, Veena; Dutt, Sanjay; Yadav, Manjulata; Mishra, Rosaline; Ramola, R C

2016-10-01

It is well known that inhalation of radon, thoron and their progeny contributes more than 50 % of natural background radiation dose to human being. The time-integrated passive measurements of radon, thoron and their progeny concentrations were carried out in the dwellings of Pauri Garhwal, Uttarakhand, India. The measurements of radon and thoron concentrations were performed by LR-115 detector-based single-entry pin-hole dosemeter, while for the measurement of progeny concentrations, LR-115 deposition-based direct radon and thoron progeny sensors technique was used. The experimental techniques and results obtained are discussed in detail. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The progeny of Legionella pneumophila in human macrophages shows unique developmental traits.

PubMed

Abdelhady, Hany; Garduño, Rafael A

2013-12-01

The Gram-negative bacterium Legionella pneumophila is an intracellular parasite of amoebae and an accidental human pathogen that causes a noncommunicable atypical pneumonia known as Legionnaires' disease (LD). In some mammalian cells (e.g. HeLa), L. pneumophila follows a biphasic developmental cycle, differentiating between a replicative form that actively multiplies intracellularly, and a mature infectious form (MIF) that emerges as progeny. To date, it is not known whether the L. pneumophila progenies that emerge from amoebae and human macrophages reach similar developmental stages. Here, we demonstrate that in relation to the fully differentiated and highly infectious MIFs that emerge from amoebae, the L. pneumophila progeny that emerges from macrophages is morphologically undifferentiated, less resistant to antibiotics and less able to initiate infections. However, the L. pneumophila progeny from macrophages did not show any defects in intracellular growth. We thus concluded that macrophage infection with L. pneumophila yields a low number of bona fide MIFs. Because MIFs are the transmissive forms of L. pneumophila produced in vivo, our results showing that they are not efficiently produced in cultured macrophages provide an initial insight into why LD is not communicable. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

Techniques to alleviate nuisance alarms observed by PCMs following 222Rn-progeny deposition on clothing.

PubMed

Justus, Alan L

2015-05-01

This paper presents technically-based techniques to deal with nuisance personnel contamination monitor (PCM) alarms. The techniques derive from the fundamental physical characteristics of radon progeny. Some PCM alarms, although valid alarms and not actually "false," could be due to nuisance naturally-occurring radionuclides (i.e., radon progeny). Based on certain observed characteristics of the radon progeny, several prompt techniques are discussed that could either remediate or at least mitigate the problem of nuisance alarms. Examples are provided which demonstrate the effective use of the techniques.

Preliminary Experiments Using a Passive Detector for Measuring Indoor 220Rn Progeny Concentrations with an Aerosol Chamber.

PubMed

Sorimachi, Atsuyuki; Tokonami, Shinji; Kranrod, Chutima; Ishikawa, Tetsuo

2015-06-01

This paper describes preliminary experiments using a passive detector for integrating measurements of indoor thoron (²²⁰Rn) progeny concentrations with an aerosol chamber. A solid state nuclear detector (CR-39) covered with a thin aluminum-vaporized polyethylene plate (Mylar film) was used to detect only alpha particles emitted from ²¹²Po due to ²²⁰Rn progeny deposited on the detector surfaces. The initial experiment showed that Mylar film with area density of more than 5 mg cm⁻² was suitable to cut off completely alpha particles of 7.7 MeV from ²¹⁴Po of ²²²Rn progeny decay. In the experiment using the passive detector, it was observed that the net track density increased linearly with an increase of time-integrating ²²⁰Rn progeny concentration. As a result of dividing deposition rates by atom concentrations, the deposition velocity was given as 0.023 cm s⁻¹ for total ²²⁰Rn progeny. The model estimates of deposition velocities were 0.330 cm s⁻¹ for unattached ²²⁰Rn progeny and 0.0011 cm s⁻¹ for aerosol-attached ²²⁰Rn progeny using Lai-Nazaroff formulae. These deposition velocities were in the same range with the results reported in the literature. It was also found that the exposure experiments showed little influence of vertical profiles and surface orientations of the passive detector in the chamber on the detection responses, which was in good agreement with that in the model estimates. Furthermore, it was inferred that the main uncertainty of the passive detector was inhomogeneous deposition of Rn progeny onto its detection surfaces.

Identification of quantitative trait loci for yield and yield components in an advanced backcross population derived from the Oryza sativa variety IR64 and the wild relative O. rufipogon.

PubMed

Septiningsih, E M; Prasetiyono, J; Lubis, E; Tai, T H; Tjubaryat, T; Moeljopawiro, S; McCouch, S R

2003-11-01

A BC(2)F(2) population developed from an interspecific cross between Oryza sativa (cv IR64) and O. rufipogon (IRGC 105491) was used in an advanced backcross QTL analysis to identify and introduce agronomically useful genes from this wild relative into the cultivated gene pool. The objectives of this study were: (1) to identify putative yield and yield component QTLs that can be useful to improve the elite cultivar IR64; (2) to compare the QTLs within this study with previously reported QTLs in rice as the basis for identifying QTLs that are stable across different environments and genetic backgrounds; and (3) to compare the identified QTLs with previously reported QTLs from maize to examine the degree of QTL conservation across the grass family. Two hundred eighty-five families were evaluated in two field environments in Indonesia, with two replications each, for 12 agronomic traits. A total of 165 markers consisting of 131 SSRs and 34 RFLPs were used to construct the genetic linkage map. By employing interval mapping and composite interval mapping, 42 QTLs were identified. Despite its inferior performance, 33% of the QTL alleles originating from O. rufipogon had a beneficial effect for yield and yield components in the IR64 background. Twenty-two QTLs (53.4%) were located in similar regions as previously reported rice QTLs, suggesting the existence of stable QTLs across genetic backgrounds and environments. Twenty QTLs (47.6%) were exclusively detected in this study, uncovering potentially novel alleles from the wild, some of which might improve the performance of the tropical indica variety IR64. Additionally, several QTLs for plant height, grain weight, and flowering time detected in this study corresponded to homeologous regions in maize containing previously detected maize QTLs for these traits.

Genetic Control of the Innate Resistance of Mice to Salmonella typhimurium: Expression of the Ity Gene in Peritoneal Macrophages Isolated In Vitro

DTIC Science & Technology

1984-07-20

Carter and Collins, 1974a; Collins and Carter, 1978; O’Brien, 1982a). S. typhimurium and certain strains of Salmonella enteritidis are facultative...tested by S. enteritidis challenge of mice chronically infected with an antigenically dissimilar Salmonella species, S. montevideo. These mice were...given 5 X lO"’’ S. enteritidis . Crosses of resistant and susceptible strains resulted in Fl progeny of a Salmonella resistant phenotype. Backcross

AFLP marking and polymorphism among progenies of Gymnema sylvestre: an important medicinal plant of India.

PubMed

Osman, Magda Abbaker; Dhawan, Sunita Singh; Bahl, Janak Raj; Darokar, Mahendra P; Khanuja, Suman P S

2011-11-01

The level of polymorphism among twelve selected progenies of Gymnema sylvestre was investigated through AFLP markers by multiplexing PCR reactions using 64 (8x8) primer combinations. Fourteen primer combinations were selected as the most suitable combination for G. sylvestre. Analysis of the 12 progenies with these 14 primer pairs produced 1689 fragments of which 972 (57.5%) were polymorphic and 485 (28.7%) were unique to a particular genotype. The number of fragments produced by individual primer pairs was in the range of 55 to 225. Out of these, polymorphic fragments were in the range of 34 (E-ACC/M-CAC) to 157 (E-AGG/M-CAG) and unique bands observed were 8 (E-ACC / M-CAC) to 69 (E-AGG/M-CAC). Different primer combinations detected different levels of polymorphism, ranging from 33% (E-AGG/ M-CAC) to 69.8% (E-AGG/ M-CAC). From the observations, it appears that the primer combinations E-AGG/M-CAC, E-AGG/CTG, E-AGG/CAG and E-ACA/CAT were the most informative for the detection of polymorphism among the progenies compared with others, since they produced a high number of unique fragments. The similarity coefficient ranged from 0.212 to 0.731. High similarity was observed between progeny S8 and S9 (73%) and high divergence between progenies S3 and S11. Among the selected progeny, S9 was found to be the most similar to the parent (63%), while genotype S11 was the most distant (36.9%).

Daylength and temperature during seed production interactively affect adaptive performance of Picea abies progenies.

PubMed

Johnsen, Oystein; Daehlen, Ola Gram; Ostreng, Geir; Skrøppa, Tore

2005-12-01

Adaptive traits in Picea abies (Norway spruce) progenies are influenced by the maternal temperatures during seed production. Here, we have extended these studies by testing the effects of maternal photoperiod and temperature on phenology and frost hardiness on progenies. Using eight phytotron rooms, seeds from three unrelated crosses were made in an environmental 2 x 2 factorial combination of long and short days and high and low temperatures. The progenies were then forced to cease growth rapidly at the end of the first growing season. An interactive memory effect was expressed the second growth season. Progenies from high temperature and short days, and from low temperatures and long days, started growth later in spring, ceased shoot growth later in summer, grew taller and were less frost hardy in the autumn than their full siblings from low temperatures and short days, and from high temperatures and long days. Norway spruce has developed a memory mechanism, regulating adaptive plasticity by photoperiod and temperature, which could counteract harmful effects of a rapidly changing climate.

Nursery performance of American and Chinese chestnuts and backcross generations in commercial tree nurseries

Treesearch

Stacy L. Clark; Scott E. Schlarbaum; Arnold M. Saxton; Fred V. Hebard

2012-01-01

The American chestnut [Castanea dentata (Marsh.) Borkh.] was decimated by an exotic fungus [Cryphonectria parasitica (Murr.) Barr] in the early 1900s. Breeding efforts with American and Chinese chestnuts (C. mollissima Blume) produced putatively blight-resistant progeny (BC3F3) in 2007. We compared two nut size...

Progeny Testing Longleaf Pine at Two Locations

Treesearch

E. Bayne Snyder; Calvin F. Bey

1978-01-01

Means for brown-spot infection and 3- and 8-year height growth were determined in progeny testing of 540 parents in two Gulfport, Mississippi, plantiflgs and an Alexandria, Louisiana, planting, and of 60 of the parents at a subsequent Alexandria planting. To estimate growth at ages 5 and 8. both degree of brown-spot infection and height growth at age 2 were necessary...

Assessment of the unattached fraction of indoor radon progeny and its contribution to dose: a pilot study in China.

PubMed

Guo, Qiuju; Zhang, Lei; Guo, Lu

2012-12-01

The unattached fraction of radon progeny (f(p)) is one of the most important factors for accurate evaluation of the effective dose from a unit of radon exposure, and it may vary greatly in different environments. For precise evaluation of the indoor radon exposure dose and the influence of unattached radon progeny, a pilot survey of f(p) in different environments was carried out in China with a portable and integrating monitor. The dose conversion factors for radon progeny are calculated with LUDEP(®) code, and the dose contributions from the unattached and the attached radon progenies were simultaneously evaluated based on the results of field measurements. The results show that even though the concentrations of radon progeny vary significantly among different indoor environments, the variations of f(p) seem relatively small (9.3-16.9%). The dose contribution from unattached radon progeny is generally larger (30.2-46.2%) in an indoor environment.

Genetic Variation Among Open-Pollinated Progeny of Eastern Cottonwood

Treesearch

R. E. Farmer

1970-01-01

Improvement programs in eastern cottonwood (Populus deltoides Bartr.) are most frequently designed to produce genetically superior clones for direct commercial use. This paper describes a progeny test to assess genetic variability on which selection might be based.

[Cytogenetic characteristics of seed progeny of trees under condition of antropogenic contamination in Voronezh town].

PubMed

Butorina, A K; Kalaev, V N; Vostrikova, T V; Miagkova, O E

2000-01-01

It has been shown that in seed progeny of Quercus robur L., Pinus sylvestris L. and Betula pendula Roth. some cytogenetical characteristics vary under conditions of contamination. Such changes may be common or specific type. Thus, the frequency of pathological mitosis increases under such conditions in all the investigated species of trees. Inhibition of mitosis was found in the progeny of the pine, and variability in the number of nucleoli was detected in the pine and oak. However, in some cases the level of pathological mitosis in the oak progeny did not differ from the control, but the mitotic activity was higher due to the presence of much more cells being at the prophase stage. In the birch progeny under conditions of contamination the mitotic index increased, with a simultaneous shifts in the peaks of mitotic activity. The possibility of using these cytological characteristics for the aims of cytogenetical monitoring is considered.

Time-averaged exposures to 220Rn and 222Rn progeny in Colorado homes.

PubMed

Martz, D E; Falco, R J; Langner, G H

1990-06-01

Week-long time-averaged exposures to naturally occurring 220Rn and 222Rn progeny have been measured at several locations in Colorado by monitoring the alpha activity collected continuously on a fixed-membrane filter. The alpha-energy spectrum associated with the activity collected on the filter was recorded every 15 min using a microcomputer-controlled alpha spectrometer. The alpha counts observed in three energy regions permitted complete separation of the contributions from each decay chain, and calculation of the separate time-averaged potential alpha-energy concentrations in air from 220Rn progeny, PAEC(Tn), and from 222Rn progeny, PAEC(Rn). The time-averaged PAEC(Tn) ranged from 0.3 to 6.9 mWL at 12 indoor locations, and the time-averaged PAEC(Rn) ranged from 1.0 to 59.0 mWL. The ratios of the indoor PAEC(Tn) to indoor PAEC(Rn) ranged from 0.09 to 0.58, with an overall average ratio of 0.32 and a standard deviation of 0.15. The 10 L min-1 flow rate through the filter was selected to approximate the air intake rate of a resting human; the time-averaged PAEC thus represents the progeny concentrations that would have been inhaled by a person breathing the same atmosphere.

Parental sex effect of parthenogenesis on progeny production and performance of Chinese Painted Quail (Coturnix chinensis).

PubMed

Ramachandran, R; Nascimento Dos Santos, M; Parker, H M; McDaniel, C D

2018-06-01

Embryonic development of an unfertilized egg, parthenogenesis, is known to occur in Chinese Painted quail. However, selection for parthenogenesis in both the dam and sire leads to a reduction in hatchability following mating. Therefore, the objective of this study was to determine if selection for parthenogenesis in the dam, sire, or both also impact their progeny performance. There were 2 lines of birds used in this trial: 1 line selected for parthenogenesis and 1 line not selected for parthenogenesis (control) yielding breeding pairs as follows: control dams + control sires (CC), control dams + parthenogenetic sires (CP), parthenogenetic dams + control sires (PC), and parthenogenetic dams + parthenogenetic sires (PP). For all progeny, a dam line main effect revealed that the parthenogenetic line dams had heavier offspring hatch weight and 4 wk body weight as well as higher 1st wk chick mortality versus control line dams. However, control line dams had the highest 4th wk chick mortality versus parthenogenetic line dams. In female virgin progeny, a dam by sire interaction revealed that PP, PC, and CP had the heaviest 1st egg in the clutch position versus CC. Also, eggs from PP had the highest number of eggs and the most female progeny exhibiting parthenogenesis versus CC. There was a linear increase in egg weight as clutch position increased for progeny from PP and CC yet a linear decline for CP. In conclusion, it appears that both the dam and sire selected for parthenogenesis impact progeny performance as parthenogenetic dams and sires additively contribute to the degree of parthenogenesis exhibited by virgin female progeny. Moreover, because parthenogenesis is known to exist in the modern poultry industry, even the accidental selection of the parthenogenetic trait in either males or females could have a negative impact on overall chick production and performance. Published by Elsevier Inc.

Surface alpha backgrounds from plate-out of radon progeny

NASA Astrophysics Data System (ADS)

Perumpilly, Gopakumar; Guiseppe, Vincente

2012-03-01

Low-background detectors operating underground aim for unprecedented low levels of radioactive backgrounds. Although the radioactive decays of airborne radon (particularly Rn-222) and its subsequent daughters present in an experiment are potential backgrounds, more troublesome is the deposition of radon daughters on detector materials. Exposure to radon at any stage of assembly of an experiment can result in surface contamination by daughters supported by the long half life (22 y) of Pb-210 on sensitive locations of a detector. We have developed a model of the radon progeny implantation using Geant4 simulations based on the low energy nuclear recoil process. We explore the alpha decays from implanted progeny on a Ge crystal as potential backgrounds for a neutrinoless double-beta decay experiment. Results of the simulations validated with alpha spectrum measurement of plate-out samples will be presented.

Factors influencing gene introgression into the allotetraploid Coffea arabica L. from its diploid relatives.

PubMed

Herrera, Juan C; Combes, Marie C; Cortina, Hernando; Lashermes, Philippe

2004-12-01

Factors controlling gene introgression into cultivated arabica coffee (Coffea arabica L.) were investigated. Interspecific triploid hybrid plants between the tetraploid species C. arabica (2n = 44) and a diploid species (2n = 22), either Coffea canephora or Coffea eugenioides, were backcrossed to C. arabica (male parent). Flow cytometric analysis of the nuclear DNA content revealed that most of the BC(1) individuals derived from triploid hybrids involving C. eugenioides were tetraploid or nearly tetraploid. Among the gametes produced by the interspecific triploid hybrids, those possessing approximately 22 chromosomes appeared strongly favored. The amount of introgression in BC(1) individuals (21 and 43 for the BC(1) progenies involving C. canephora and C. eugenioides, respectively) was estimated using species-specific microsatellite markers. A large number of introgressed markers was observed in all BC(1) individuals. Nevertheless, while the frequency of introgressed markers seemed as expected, assuming random chromosome segregation and diploid gamete formation, in the BC(1) derived from triploid hybrids involving C. canephora, this frequency appeared significantly lower in the BC(1) derived from triploid hybrids involving C. eugenioides. Furthermore, the comparison of reciprocal progenies between C. arabica and triploid interspecific hybrids (C. arabica x C. canephora) used as male or female parent revealed a very strong effect of the backcross direction.

Integrated QTL detection for key breeding traits in multiple peach progenies.

PubMed

Hernández Mora, José R; Micheletti, Diego; Bink, Marco; Van de Weg, Eric; Cantín, Celia; Nazzicari, Nelson; Caprera, Andrea; Dettori, Maria Teresa; Micali, Sabrina; Banchi, Elisa; Campoy, José Antonio; Dirlewanger, Elisabeth; Lambert, Patrick; Pascal, Thierry; Troggio, Michela; Bassi, Daniele; Rossini, Laura; Verde, Ignazio; Quilot-Turion, Bénédicte; Laurens, François; Arús, Pere; Aranzana, Maria José

2017-06-06

Peach (Prunus persica (L.) Batsch) is a major temperate fruit crop with an intense breeding activity. Breeding is facilitated by knowledge of the inheritance of the key traits that are often of a quantitative nature. QTLs have traditionally been studied using the phenotype of a single progeny (usually a full-sib progeny) and the correlation with a set of markers covering its genome. This approach has allowed the identification of various genes and QTLs but is limited by the small numbers of individuals used and by the narrow transect of the variability analyzed. In this article we propose the use of a multi-progeny mapping strategy that used pedigree information and Bayesian approaches that supports a more precise and complete survey of the available genetic variability. Seven key agronomic characters (data from 1 to 3 years) were analyzed in 18 progenies from crosses between occidental commercial genotypes and various exotic lines including accessions of other Prunus species. A total of 1467 plants from these progenies were genotyped with a 9 k SNP array. Forty-seven QTLs were identified, 22 coinciding with major genes and QTLs that have been consistently found in the same populations when studied individually and 25 were new. A substantial part of the QTLs observed (47%) would not have been detected in crosses between only commercial materials, showing the high value of exotic lines as a source of novel alleles for the commercial gene pool. Our strategy also provided estimations on the narrow sense heritability of each character, and the estimation of the QTL genotypes of each parent for the different QTLs and their breeding value. The integrated strategy used provides a broader and more accurate picture of the variability available for peach breeding with the identification of many new QTLs, information on the sources of the alleles of interest and the breeding values of the potential donors of such valuable alleles. These results are first-hand information for

Analysis of radon and thoron progeny measurements based on air filtration.

PubMed

Stajic, J M; Nikezic, D

2015-02-01

Measuring of radon and thoron progeny concentrations in air, based on air filtration, was analysed in order to assess the reliability of the method. Changes of radon and thoron progeny activities on the filter during and after air sampling were investigated. Simulation experiments were performed involving realistic measuring parameters. The sensitivity of results (radon and thoron concentrations in air) to the variations of alpha counting in three and five intervals was studied. The concentration of (218)Po showed up to be the most sensitive to these changes, as was expected because of its short half-life. The well-known method for measuring of progeny concentrations based on air filtration is rather unreliable and obtaining unrealistic or incorrect results appears to be quite possible. A simple method for quick estimation of radon potential alpha energy concentration (PAEC), based on measurements of alpha activity in a saturation regime, was proposed. Thoron PAEC can be determined from the saturation activity on the filter, through beta or alpha measurements. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Growth and Crown Vigor of 25 Year-Old Shortleaf Pine Progenies on a Littleleaf Disease Site

Treesearch

Stanley J. Zarnoch; John L. Ruehle; Roger P. Belanger; Donald H. Marx; W. Craig Bryan

1994-01-01

On a littleleaf disease site in South Carolina, most of the control-pollinated progeny of shrotleaf pines that appeared to be reesistant to the disease outperformed a check seedlot through age 25. Rankings of progeny based on volume changed little between ages 17 and 25.

Filter for on-line air monitor unaffected by radon progeny and method of using same

DOEpatents

Phillips, Terrance D.; Edwards, Howard D.

1999-01-01

An apparatus for testing air having contaminants and radon progeny therein. The apparatus includes a sampling box having an inlet for receiving the air and an outlet for discharging the air. The sampling box includes a filter made of a plate of sintered stainless steel. The filter traps the contaminants, yet allows at least a portion of the radon progeny to pass therethrough. A method of testing air having contaminants and radon progeny therein. The method includes providing a testing apparatus that has a sampling box with an inlet for receiving the air and an outlet for discharging the air, and has a sintered stainless steel filter disposed within said sampling box; drawing air from a source into the sampling box using a vacuum pump; passing the air through the filter; monitoring the contaminants trapped by the filter; and providing an alarm when a selected level of contaminants is reached. The filter traps the contaminants, yet allows at least a portion of the radon progeny to pass therethrough.

Mixed models for selection of Jatropha progenies with high adaptability and yield stability in Brazilian regions.

PubMed

Teodoro, P E; Bhering, L L; Costa, R D; Rocha, R B; Laviola, B G

2016-08-19

The aim of this study was to estimate genetic parameters via mixed models and simultaneously to select Jatropha progenies grown in three regions of Brazil that meet high adaptability and stability. From a previous phenotypic selection, three progeny tests were installed in 2008 in the municipalities of Planaltina-DF (Midwest), Nova Porteirinha-MG (Southeast), and Pelotas-RS (South). We evaluated 18 families of half-sib in a randomized block design with three replications. Genetic parameters were estimated using restricted maximum likelihood/best linear unbiased prediction. Selection was based on the harmonic mean of the relative performance of genetic values method in three strategies considering: 1) performance in each environment (with interaction effect); 2) performance in each environment (with interaction effect); and 3) simultaneous selection for grain yield, stability and adaptability. Accuracy obtained (91%) reveals excellent experimental quality and consequently safety and credibility in the selection of superior progenies for grain yield. The gain with the selection of the best five progenies was more than 20%, regardless of the selection strategy. Thus, based on the three selection strategies used in this study, the progenies 4, 11, and 3 (selected in all environments and the mean environment and by adaptability and phenotypic stability methods) are the most suitable for growing in the three regions evaluated.

222Rn progeny surface deposition and resuspension--residential materials.

PubMed

Leonard, B E

1995-07-01

The radiological hazard of radon gas to occupants in residential environments is from the particulate progeny 218Po, 214Pb, 214Bi, and 214Po, rather than 222Rn itself. Attachment to aerosols, plateout, and resuspension impact on the progeny airborne concentrations. Plateout rate and resuspension factors were measured for air change (ventilation) rates, 0.01 to 1.0 h-1, in a 0.28 m3 test chamber for interior residential materials of wallboard, drapery, carpet, ceiling tile, and concrete, and from 0.05 to 2.5 h-i for hardwood and glass. The overall accuracy of the plateout rate values is estimated to be +/- 13% standard deviation. For the different materials, the plateout rates for 218Po progeny varied by a factor of nearly six. Drapery gave the largest plateout rates. Resuspension rate factors, R, were measured for hardwood, wallboard, drapery, carpet, and glass by a new time-dependent measurement method based on the difference in buildup rate of 214Po to equilibrium caused by resuspension. Values for R obtained for hardwood, wallboard, drapery, carpet and glass were 0.31, 0.29, 0.44, 0.55, and 0.36, respectively ( +/- 30% standard deviation). All measurements were made in a continuous air conditioned interior environment maintaining temperature at 22.2 +/- 1.1 degrees C and relative humidity of 30% +/- 10%. Computations were made of equivalent plateout rates and equilibrium fractions for a standard 5 m x 5 m x 3 m high room to provide values to compare with other work.

Genotypic gain with simultaneous selection of production, nutrition, and culinary traits in cowpea crosses and backcrosses using mixed models.

PubMed

Oliveira, D G; Rocha, M M; Damasceno-Silva, K J; Sá, F V; Lima, L R L; Resende, M D V

2017-08-17

The aim of this study was to estimate the genotypic gain with simultaneous selection of production, nutrition, and culinary traits in cowpea crosses and backcrosses and to compare different selection indexes. Eleven cowpea populations were evaluated in a randomized complete block design with four replications. Fourteen traits were evaluated, and the following parameters were estimated: genotypic variation coefficient, genotypic determination coefficient, experimental quality indicator and selection reliability, estimated genotypic values ​​- BLUE, genotypic correlation coefficient among traits, and genotypic gain with simultaneous selection of all traits. The genotypic gain was estimated based on tree selection indexes: classical, multiplicative, and the sum of ranks. The genotypic variation coefficient was higher than the environmental variation coefficient for the number of days to start flowering, plant type, the weight of one hundred grains, grain index, and protein concentration. The majority of the traits presented genotypic determination coefficient from medium to high magnitude. The identification of increases in the production components is associated with decreases in protein concentration, and the increase in precocity leads to decreases in protein concentration and cooking time. The index based on the sum of ranks was the best alternative for simultaneous selection of traits in the cowpea segregating populations resulting from the crosses and backcrosses evaluated, with emphasis on the F 4 BC 12 , F 4 C 21 , and F 4 C 12 populations, which had the highest genotypic gains.

Radon progeny size distributions and enhanced deposition effects from high radon concentrations in an enclosed chamber.

PubMed

Leonard, Bobby E

2004-01-01

Prior work studying radon progeny in a small enclosed chamber found that at high (222)Rn concentrations an enhanced surface deposition was observed. Subsequent measurements for unfiltered air showed minimal charged particle mobility influence. Progeny particle size measurements reported here, performed at the US Department of Energy Environmental Measurement Laboratory (now with Home Security Department), using the EML graded screen array (GSA) system show in unfiltered air that the high (222)Rn levels causes a reduction in the attached (218)Po progeny airborne particulates and formation of additional normal sized unattached ( approximately 0.80 nm) and also even smaller (218)Po below 0.50 nm. At a (222)Rn level of 51 kBq m(-3), 73% of all (218)Po are of a mean particle diameter of about 0.40 +/- 0.02 nm. At this (222)Rn level, the ratio of (218)Po to (222)Rn airborne concentrations is reduced significantly from the concentration ratio at low (222)Rn levels. Similar reductions and size reformations were observed for the (214)Pb and (214)Bi/Po progeny. The particle size changes are further confirmed using the plateout rates and corresponding deposition velocities. The Crump and Seinfeld deposition theory provides the corresponding particle diffusion coefficients. With the diffusion coefficient to ultrafine clustered particle diameter correlation of Ramamurthi and Hopke, good agreement is obtained between EML GSA and deposition velocity data down to 0.40 nm. Strong evidence is presented that the progeny size reduction is due to, as a result of air ionization, the increased neutralization rate (primarily from electron scavenging of OH molecules) of the initially charged progeny. This is shown to increase with the (1/2) power of (222)Rn concentration and relative humidity as well as increased air change rate in the chamber. These results imply that at (222)Rn levels above 50 kBq m(-3), at relative humidity of 52%, a considerable reduction in lung dose could occur from

Invariants of the Jacobi-Porstendorfer room model for radon progeny in indoor air.

PubMed

Thomas, Josef; Jilek, Karel

2012-06-01

The Jacobi-Porstendörfer room model, describing the dynamical behaviour of radon and radon progeny in indoor air, has been successfully used for decades. The inversion of the model-the determination of the five parameters from measured results which provide better information on the room environment than mere ratios of unattached and attached radon progeny-is treated as an algebraic task. The linear interdependence of the used equations strongly limits the algebraic invertibility of experimental results. For a unique solution, the fulfilment of two invariants of the room model for the measured results is required. Non-fulfilment of these model invariants by the measured results leads to a set of non-identical solutions and indicates the violation of the conditions required by the room model or the incorrectness or excessive uncertainties of the measured results. The limited and non-unique algebraic invertibility of the room model is analysed numerically using our own data for the radon progeny.

A family business: stem cell progeny join the niche to regulate homeostasis.

PubMed

Hsu, Ya-Chieh; Fuchs, Elaine

2012-01-23

Stem cell niches, the discrete microenvironments in which the stem cells reside, play a dominant part in regulating stem cell activity and behaviours. Recent studies suggest that committed stem cell progeny become indispensable components of the niche in a wide range of stem cell systems. These unexpected niche inhabitants provide versatile feedback signals to their stem cell parents. Together with other heterologous cell types that constitute the niche, they contribute to the dynamics of the microenvironment. As progeny are often located in close proximity to stem cell niches, similar feedback regulations may be the underlying principles shared by different stem cell systems.

Genetic Control of Wayward Pluripotent Stem Cells and Their Progeny after Transplantation

PubMed Central

Kiuru, Maija; Boyer, Julie L.; O’Connor, Timothy P.; Crystal, Ronald G.

2011-01-01

The proliferative capacity of pluripotent stem cells and their progeny brings a unique aspect to therapeutics, in that once a transplant is initiated the therapist no longer has control of the therapy. In the context of the recent FDA approval of a human ESC trial and report of a neuronal-stem-cell-derived tumor in a human trial, strategies need to be developed to control wayward pluripotent stem cells. Here, we focus on one approach: direct genetic modification of the cells prior to transplantation with genes that can prevent the adverse events and/or eliminate the transplanted cells and their progeny. PMID:19341619

Variability and performance evaluation of introgressed Nigerian dura x Deli dura oil palm progenies.

PubMed

Noh, A; Rafii, M Y; Mohd Din, A; Kushairi, A; Norziha, A; Rajanaidu, N; Latif, M A; Malek, M A

2014-04-03

Twelve introgressed oil palm (Elaeis guineensis) progenies of Nigerian dura x Deli dura were evaluated for bunch yield, yield attributes, bunch quality components and vegetative characters at the Malaysian Palm Oil Board Research Station, in Keratong, Pahang, Malaysia. Analysis of variance revealed significant to highly significant genotypic differences, indicating sufficient genetic variability among the progenies for bunch yield and its attributes, vegetative characters and bunch quality components, except fruit to bunch ratio. Fresh fruit bunch yield ranged from 167 kg·palm(-1)·year(-1) in PK1330 to 212 kg·palm(-1)·year(-1) in PK1351, with a mean yield of 192 kg·palm(-1)·year(-1). Among the progeny, PK1313 had the highest oil to bunch ratio (19.36%), due to its high mesocarp to fruit ratio, fruit to bunch ratio and low shell to fruit ratio. Among the progenies, PK1313 produced the highest oil yield of 31.4 kg·palm(-1)·year(-1), due to a high mesocarp to fruit ratio (61.2%) and a low shell to fruit ratio (30.7%), coupled with high fruit to bunch ratio (65.6%). PK1330 was found promising for selection, as it had desirable vegetative characters, including smaller petiole cross section (27.15 cm2), short rachis length (4.83 m), short palm height (1.85 m), and the lowest leaf number (164.6), as these vegetative characters are prerequisites for selecting palms for high density planting and high yield per hectare. The genetic variability among the progenies was found to be high, indicating ample scope for further breeding, followed by selection.

STUDY OF RADIATION EXPOSURE DUE TO RADON, THORON AND THEIR PROGENY IN THE INDOOR ENVIRONMENT OF RAJPUR REGION OF UTTARAKHAND HIMALAYA.

PubMed

Kandari, Tushar; Aswal, Sunita; Prasad, Mukesh; Pant, Preeti; Bourai, A A; Ramola, R C

2016-10-01

In the present study, the measurements of indoor radon, thoron and their progeny concentrations have been carried out in the Rajpur region of Uttarakhand, Himalaya, India by using LR-115 solid-state nuclear track detector-based time-integrated techniques. The gas concentrations have been measured by single-entry pin-hole dosemeter technique, while for the progeny concentrations, deposition-based Direct Thoron and Radon Progeny Sensor technique has been used. The radiation doses due to the inhalation of radon, thoron and progeny have also been determined by using obtained concentrations of radon, thoron and their progeny in the study area. The average radon concentration varies from 75 to 123 Bq m -3 with an overall average of 89 Bq m -3 The average thoron concentration varies from 29 to 55 Bq m -3 with an overall average of 38 Bq m -3 The total annual effective dose received due to radon, thoron and their progeny varies from 2.4 to 4.1 mSv y -1 with an average of 2.9 mSv y -1 While the average equilibrium factor for radon and its progeny was found to be 0.39, for thoron and its progeny, it was 0.06. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Fruiting Body Formation of Cordyceps militaris from Multi-Ascospore Isolates and Their Single Ascospore Progeny Strains

PubMed Central

Shrestha, Bhushan; Han, Sang-Kuk; Sung, Jae-Mo

2012-01-01

Interest in commercial cultivation and product development of Cordyceps species has shown a recent increase. Due to its biochemical and pharmacological effects, Cordyceps militaris, commonly known as orange caterpillar fungus, is being investigated with great interest. Cultivation of C. militaris has been practiced on a large scale in order to fulfill a demand for scientific investigation and product development. Isolates of C. militaris can be easily established from both spores and tissue. For isolation of spores, ascospores released from mature stromata are trapped in sterile medium. Multi-ascospore isolates, as well as combinations of single ascospore strains, are used for production of fruiting bodies. Progeny ascospore strains can be isolated from artificial fruiting bodies, thus, the cycle of fruiting body production can be continued for a long period of time. In this study, we examined fruiting body production from multi-ascospore isolates and their progeny strains for three generations. F1 progeny strains generally produced a larger number of fruiting bodies, compared with their mother multi-ascospore isolates; however, F2 and F3 progeny strains produced fewer fruiting bodies. Optimum preservation conditions could help to increase the vitality of the progeny strains. In order to retain the fruiting ability of the strains, further testing of various methods of preservation and different methods for isolation should be performed. PMID:22870051

Study on peak shape fitting method in radon progeny measurement.

PubMed

Yang, Jinmin; Zhang, Lei; Abdumomin, Kadir; Tang, Yushi; Guo, Qiuju

2015-11-01

Alpha spectrum measurement is one of the most important methods to measure radon progeny concentration in environment. However, the accuracy of this method is affected by the peak tailing due to the energy losses of alpha particles. This article presents a peak shape fitting method that can overcome the peak tailing problem in most situations. On a typical measured alpha spectrum curve, consecutive peaks overlap even their energies are not close to each other, and it is difficult to calculate the exact count of each peak. The peak shape fitting method uses combination of Gaussian and exponential functions, which can depict features of those peaks, to fit the measured curve. It can provide net counts of each peak explicitly, which was used in the Kerr method of calculation procedure for radon progeny concentration measurement. The results show that the fitting curve fits well with the measured curve, and the influence of the peak tailing is reduced. The method was further validated by the agreement between radon equilibrium equivalent concentration based on this method and the measured values of some commercial radon monitors, such as EQF3220 and WLx. In addition, this method improves the accuracy of individual radon progeny concentration measurement. Especially for the (218)Po peak, after eliminating the peak tailing influence, the calculated result of (218)Po concentration has been reduced by 21 %. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Lung dosimetry for inhaled long-lived radionuclides and radon progeny.

PubMed

Hussain, M; Winkler-Heil, R; Hofmann, W

2011-05-01

The current version of the stochastic lung dosimetry model IDEAL-DOSE considers deposition in the whole tracheobronchial (TB) and alveolar airway system, while clearance is restricted to TB airways. For the investigation of doses produced by inhaled long-lived radionuclides (LLR) together with short-lived radon progeny, alveolar clearance has to be considered. Thus, present dose calculations are based on the average transport rates proposed for the revision of the ICRP human respiratory tract model. The results obtained indicate that LLR cleared from the alveolar region can deliver up to two to six times higher doses to the TB region when compared with the doses from directly deposited particles. Comparison of LLR doses with those of short-lived radon progeny indicates that LLR in uranium mines can deliver up to 5 % of the doses predicted for the short-lived radon daughters.

Phenotypic analysis of first-year traits in a pseudo-backcross {(slash x loblolly) x slash} and the ope-pollinated families of the pure-species progenitors

Treesearch

Patricio R. Munoz Del Valle; Dudley A. Huber; John R. Butnor

2011-01-01

A single test, including one pseudo-backcross (Pinus elliottii x Pinus taeda) x P. elliottii and openpollinated families of the pure species progenitors, was established in North Central Florida in December 2007 to study the transfer of the fast-growing characteristics from a P. taeda L. (loblolly pine) parent into the P. elliottii Engelm. (slash pine) background....

Adversity before Conception Will Affect Adult Progeny in Rats

ERIC Educational Resources Information Center

Shachar-Dadon, Alice; Schulkin, Jay; Leshem, Micah

2009-01-01

The authors investigated whether adversity in a female, before she conceives, will influence the affective and social behavior of her progeny. Virgin female rats were either undisturbed (controls) or exposed to varied, unpredictable, stressors for 7 days (preconceptual stress [PCS]) and then either mated immediately after the end of the stress…

A family business: stem cell progeny join the niche to regulate homeostasis

PubMed Central

Hsu, Ya-Chieh; Fuchs, Elaine

2012-01-01

Stem cell niches, the discrete microenvironments in which the stem cells reside, play a dominant part in regulating stem cell activity and behaviours. Recent studies suggest that committed stem cell progeny become indispensable components of the niche in a wide range of stem cell systems. These unexpected niche inhabitants provide versatile feedback signals to their stem cell parents. Together with other heterologous cell types that constitute the niche, they contribute to the dynamics of the microenvironment. As progeny are often located in close proximity to stem cell niches, similar feedback regulations may be the underlying principles shared by different stem cell systems. PMID:22266760

Lung dosimetry for inhaled radon progeny in smokers.

PubMed

Baias, Paul F; Hofmann, Werner; Winkler-Heil, Renate; Cosma, Constantin; Duliu, Octavian G

2010-02-01

Cigarette smoking may change the morphological and physiological parameters of the lung. Thus the primary objective of the present study was to investigate to what extent these smoke-induced changes can modify deposition, clearance and resulting doses of inhaled radon progeny relative to healthy non-smokers (NSs). Doses to sensitive bronchial target cells were computed for four categories of smokers: (1) Light, short-term (LST) smokers, (2) light, long-term (LLT) smokers, (3) heavy, short-term (HST) smokers and (4) heavy, long-term (HLT) smokers. Because of only small changes of morphological and physiological parameters, doses for the LST smokers hardly differed from those for NSs. For LLT and HST smokers, even a protective effect could be observed, caused by a thicker mucus layer and increased mucus velocities. Only in the case of HLT smokers were doses higher by about a factor of 2 than those for NSs, caused primarily by impaired mucociliary clearance, higher breathing frequency, reduced lung volume and airway obstructions. These higher doses suggest that the contribution of inhaled radon progeny to the risk of lung cancer in smokers may be higher than currently assumed on the basis of NS doses.

Detection of a transient mitochondrial DNA heteroplasmy in the progeny of crossed genetically divergent isolates of arbuscular mycorrhizal fungi.

PubMed

de la Providencia, Ivan Enrique; Nadimi, Maryam; Beaudet, Denis; Morales, Gabriela Rodriguez; Hijri, Mohamed

2013-10-01

Nonself fusion and nuclear genetic exchange have been documented in arbuscular mycorrhizal fungi (AMF), particularly in Rhizophagus irregularis. However, mitochondrial transmission accompanying nonself fusion of genetically divergent isolates remains unknown. Here, we tested the hypothesis that mitochondrial DNA (mtDNA) heteroplasmy occurs in the progeny of spores, obtained by crossing genetically divergent mtDNAs in R. irregularis isolates. Three isolates of geographically distant locations were used to investigate nonself fusions and mtDNA transmission to the progeny. We sequenced two additional mtDNAs of two R. irregularis isolates and developed isolate-specific size-variable markers in intergenic regions of these isolates and those of DAOM-197198. We achieved three crossing combinations in pre-symbiotic and symbiotic phases. Progeny spores per crossing combination were genotyped using isolate-specific markers. We found evidence that nonself recognition occurs between isolates originating from different continents both in pre-symbiotic and symbiotic phases. Genotyping patterns of individual spores from the progeny clearly showed the presence of markers of the two parental mtDNA haplotypes. Our results demonstrate that mtDNA heteroplasmy occurs in the progeny of the crossed isolates. However, this heteroplasmy appears to be a transient stage because all the live progeny spores that were able to germinate showed only one mtDNA haplotype. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

Biochemical evaluation of triploid progenies of diploid × tetraploid breeding populations of Camellia for genotypes rich in catechin and caffeine.

PubMed

Das, Sourabh Kumar; Sabhapondit, Santanu; Ahmed, Giasuddin; Das, Sudripta

2013-06-01

To verify the quality of triploid varieties of Camellia tea species at the secondary metabolite level, we tested caffeine and catechin profiles of 97 F(1) segregating progenies in two breeding populations with a common tetraploid parent and diploid parents of two geographic and varietal origins. Catechin and caffeine levels of the triploid progenies were quantified and compared against their diploid parent. Some of the progenies showed better performance than their diploid parent. Most of the progenies of the diploid C. sinensis × tetraploid cross showed heterosis for caffeine and EGCG. Progenies of the C. assamica subsp. lasiocalyx × tetraploid cross showed heterosis for +C, EC, EGC, and TC. The genomic contributions of the diploid parent seem to be the main factor in the variation between the two populations. Our studies showed quantitative enhancement of some of the quality-related parameters in tea, providing a platform to refocus on this classical breeding approach for developing quality cultivars in tea.

Autumn frost hardiness in Norway spruce plus tree progeny and trees of the local and transferred provenances in central Sweden.

PubMed

Hannerz, Mats; Westin, Johan

2005-09-01

Reforestation with provenances from locations remote from the planting site (transferred provenances) or the progeny of trees of local provenances selected for superior form and vigor (plus trees) offer alternative means to increase yield over that obtained by the use of seed from unselected trees of the local provenance. Under Swedish conditions, Norway spruce (Picea abies (L.) Karst.) of certain transferred provenances generally has an advantage in productivity relative to the local provenance comparable to that of progeny of plus trees. The aim of this study was to explore the extent to which productivity gains achieved by provenance transfer or the use of plus tree progeny are associated with reductions in autumn frost hardiness, relative to that of trees of the local provenance. In a field trial with 19-year-old trees in central Sweden, bud hardiness was tested on four occasions during the autumn of 2002. Trees of the local provenance were compared with trees of a south Swedish provenance originating 3 degrees of latitude to the south, a Belarusian provenance and the progeny of plus trees of local origin. The Belarusian provenance was the least hardy and the local provenance the most hardy, with plus tree progeny and the south Swedish provenance being intermediate in hardiness. Both the Belarusian provenance and the plus tree progeny were significantly taller than trees of the other populations. Within provenances, tree height was negatively correlated with autumn frost hardiness. Among the plus tree progeny, however, no such correlation between tree height and autumn frost hardiness was found. It is concluded that although the gain in productivity achieved by provenance transfer from Belarus was comparable to that achieved by using the progeny of plus trees of the local provenance, the use of trees of the Belarus provenance involved an increased risk of autumn frost damage because of later hardening.

Nonhereditary enhancement of progeny growth

NASA Technical Reports Server (NTRS)

Khan, Amir S.; Fiorotto, Marta L.; Hill, Leigh-Anne; Malone, P. Brandon; Cummings, Kathleen K.; Parghi, Deena; Schwartz, Robert J.; Smith, Roy G.; Draghia-Akli, Ruxandra

2002-01-01

The im electroporated injection of a protease-resistant GH-releasing hormone cDNA into rat dams at 16 d gestation resulted in enhanced long-term growth of the F(1) offspring. The offspring were significantly heavier by 2 wk of age, and the difference was sustained to 10 wk of age. Consistent with their augmented growth, the plasma IGF-I concentration of the F(1) progeny was increased significantly. The pituitary gland of the offspring was significantly heavier and contained an increased number of somatotrophs and PRL-secreting cells, which is indicative of modification of cell lineage differentiation. These unique findings demonstrate that enhanced GH-releasing hormone expression in pregnant dams can result in intergenerational growth promotion by altering development of the pituitary gland in the offspring.

Alpha particle spectroscopy in radon/thoron progeny measurements.

PubMed

Thiessen, N P

1994-12-01

A comparison is made between the relative variances and counting time requirements for obtaining radon and thoron progeny air concentrations from total alpha count data and from spectroscopically resolved alpha count data collected from air sampling filters. Spectral resolution is shown to have significant advantages, especially in mixed radon/thoron atmospheres. Systematic biases resulting from imperfect energy peak resolution are shown to be subject to accurate mathematical compensation.

Intercomparison of active, passive and continuous instruments for radon and radon progeny measurements in the EML chamber and test facility

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

George, A.C.; Knutson, E.O.; Tu, K.W.

1995-12-01

The results from the May 1995 Intercomparison of Active, Passive and Continuous Instruments for Radon and Radon Progeny Measurement conducted in the EML radon exposure and test facility are presented. Represented were 13 participants that measure radon with open faced and diffusion barrier activated carbon collectors, 10 with nuclear alpha track detectors, 9 with short-term and long-term electret/ionization chambers, and 13 with active and passive commercial electronic continuous monitors. For radon progeny, there were four participants that came in person to take part in the grab sampling methodology for measuring individual radon progeny and the potential alpha energy concentration (PAEC).more » There were 11 participants with continuous and integrating commercial electronic instruments that are used for measuring the PAEC. The results indicate that all the tested instruments that measure radon fulfill their intended purpose. All instruments and methods used for grab sampling for radon progeny did very well. However, most of the continuous and integrating electronic instruments used for measuring the PAEC or working level appear to underestimate the potential risk from radon progeny when the concentration of particles onto which the radon progeny are attached is <5,000 cm{sup -3}.« less

QTL detection for rice grain quality traits using an interspecific backcross population derived from cultivated Asian (O. sativa L.) and African (O. glaberrima S.) rice.

PubMed

Li, Jiming; Xiao, Jinhua; Grandillo, Silvana; Jiang, Longying; Wan, Yizhen; Deng, Qiyun; Yuan, Longping; McCouch, Susan R

2004-08-01

An interspecific advanced backcross population derived from a cross between Oryza sativa "V20A" (a popular male-sterile line used in Chinese rice hybrids) and Oryza glaberrima (accession IRGC No. 103544 from Mali) was used to identify quantitative trait loci (QTL) associated with grain quality and grain morphology. A total of 308 BC3F1 hybrid families were evaluated for 16 grain-related traits under field conditions in Changsha, China, and the same families were evaluated for RFLP and SSR marker segregation at Cornell University (Ithaca, N.Y.). Eleven QTL associated with seven traits were detected in six chromosomal regions, with the favorable allele coming from O. glaberrima at eight loci. Favorable O. glaberrima alleles were associated with improvements in grain shape and appearance, resulting in an increase in kernel length, transgressive variation for thinner grains, and increased length to width ratio. Oryza glaberrima alleles at other loci were associated with potential improvements in crude protein content and brown rice yield. These results suggested that genes from O. glaberrima may be useful in improving specific grain quality characteristics in high-yielding O. sativa hybrid cultivars.

Identification of a rice gene (Bph 1) conferring resistance to brown planthopper (Nilaparvata lugens Stal) using STS markers.

PubMed

Kim, Suk-Man; Sohn, Jae-Keun

2005-08-31

This study was carried out to identify a high-resolution marker for a gene conferring resistance to brown planthopper (BPH) biotype 1, using japonica type resistant lines. Bulked segregant analyses were conducted using 520 RAPD primers to identify RAPD fragments linked to the BPH resistance gene. Eleven RAPDs were shown to be polymorphic amplicons between resistant and susceptible progeny. One of these primers, OPE 18, which amplified a 923 bp band tightly linked to resistance, was converted into a sequence-tagged-site (STS) marker. The STS marker, BpE18-3, was easily detectable as a dominant band with tight linkage (3.9cM) to Bph1. It promises to be useful as a marker for assisted selection of resistant progeny in backcross breeding programs to introgress the resistance gene into elite japonica cultivars.

The Effect of Pollen Source vs. Flower Type on Progeny Performance and Seed Predation under Contrasting Light Environments in a Cleistogamous Herb

PubMed Central

Munguía-Rosas, Miguel A.; Campos-Navarrete, María J.; Parra-Tabla, Víctor

2013-01-01

Dimorphic cleistogamy is a specialized form of mixed mating system where a single plant produces both open, potentially outcrossed chasmogamous (CH) and closed, obligately self-pollinated cleistogamous (CL) flowers. Typically, CH flowers and seeds are bigger and energetically more costly than those of CL. Although the effects of inbreeding and floral dimorphism are critical to understanding the evolution and maintenance of cleistogamy, these effects have been repeatedly confounded. In an attempt to separate these effects, we compared the performance of progeny derived from the two floral morphs while controlling for the source of pollen. That is, flower type and pollen source effects were assessed by comparing the performance of progeny derived from selfed CH vs. CL and outcrossed CH vs. selfed CH flowers, respectively. The experiment was carried out with the herb Ruellia nudiflora under two contrasting light environments. Outcrossed progeny generally performed better than selfed progeny. However, inbreeding depression ranges from low (1%) to moderate (36%), with the greatest value detected under shaded conditions when cumulative fitness was used. Although flower type generally had less of an effect on progeny performance than pollen source did, the progeny derived from selfed CH flowers largely outperformed the progeny from CL flowers, but only under shaded conditions and when cumulative fitness was taken into account. On the other hand, the source of pollen and flower type influenced seed predation, with selfed CH progeny the most heavily attacked by predators. Therefore, the effects of pollen source and flower type are environment-dependant and seed predators may increase the genetic differences between progeny derived from CH and CL flowers. Inbreeding depression alone cannot account for the maintenance of a mixed mating system in R. nudiflora and other unidentified mechanisms must thus be involved. PMID:24260515

The effect of pollen source vs. flower type on progeny performance and seed predation under contrasting light environments in a cleistogamous herb.

PubMed

Munguía-Rosas, Miguel A; Campos-Navarrete, María J; Parra-Tabla, Víctor

2013-01-01

Dimorphic cleistogamy is a specialized form of mixed mating system where a single plant produces both open, potentially outcrossed chasmogamous (CH) and closed, obligately self-pollinated cleistogamous (CL) flowers. Typically, CH flowers and seeds are bigger and energetically more costly than those of CL. Although the effects of inbreeding and floral dimorphism are critical to understanding the evolution and maintenance of cleistogamy, these effects have been repeatedly confounded. In an attempt to separate these effects, we compared the performance of progeny derived from the two floral morphs while controlling for the source of pollen. That is, flower type and pollen source effects were assessed by comparing the performance of progeny derived from selfed CH vs. CL and outcrossed CH vs. selfed CH flowers, respectively. The experiment was carried out with the herb Ruellia nudiflora under two contrasting light environments. Outcrossed progeny generally performed better than selfed progeny. However, inbreeding depression ranges from low (1%) to moderate (36%), with the greatest value detected under shaded conditions when cumulative fitness was used. Although flower type generally had less of an effect on progeny performance than pollen source did, the progeny derived from selfed CH flowers largely outperformed the progeny from CL flowers, but only under shaded conditions and when cumulative fitness was taken into account. On the other hand, the source of pollen and flower type influenced seed predation, with selfed CH progeny the most heavily attacked by predators. Therefore, the effects of pollen source and flower type are environment-dependant and seed predators may increase the genetic differences between progeny derived from CH and CL flowers. Inbreeding depression alone cannot account for the maintenance of a mixed mating system in R. nudiflora and other unidentified mechanisms must thus be involved.

Inhalation dose assessment of indoor radon progeny using biokinetic and dosimetric modeling and its application to Jordanian population.

PubMed

Al-Jundi, J; Li, W B; Abusini, M; Tschiersch, J; Hoeschen, C; Oeh, U

2011-06-01

High indoor radon concentrations in Jordan result in internal exposures of the residents due to the inhalation of radon and its short-lived progeny. It is therefore important to quantify the annual effective dose and further the radiation risk to the radon exposure. This study describes the methodology and the biokinetic and dosimetric models used for calculation of the inhalation doses exposed to radon progeny. The regional depositions of aerosol particles in the human respiratory tract were firstly calculated. For the attached progeny, the activity median aerodynamic diameters of 50 nm, 230 nm and 2500 nm were chosen to represent the nucleation, accumulation and coarse modes of the aerosol particles, respectively. For the unattached progeny, the activity median thermodynamic diameter of 1 nm was chosen to represent the free progeny nuclide in the room air. The biokinetic models developed by the International Commission on Radiological Protection (ICRP) were used to calculate the nuclear transformations of radon progeny in the human body, and then the dosimetric model was applied to estimate the organ equivalent doses and the effective doses with the specific effective energies derived from the mathematical anthropomorphic phantoms. The dose conversion coefficient estimated in this study was 15 mSv WLM(-1) which was in the range of the values of 6-20 mSv WLM(-1) reported by other investigators. Implementing the average indoor radon concentration in Jordan, the annual effective doses were calculated to be 4.1 mSv y(-1) and 0.08 mSv y(-1) due to the inhalation of radon progeny and radon gas, respectively. The total annual effective dose estimated for Jordanian population was 4.2 mSv y(-1). This high annual effective dose calculated by the dosimetric approach using ICRP biokinetic and dosimetric models resulted in an increase of a factor of two in comparison to the value by epidemiological study. This phenomenon was presented by the ICRP in its new published

Optimization of the Timepix chip to measurement of radon, thoron and their progenies.

PubMed

Janik, Miroslaw; Ploc, Ondrej; Fiederle, Michael; Procz, Simon; Kavasi, Norbert

2016-01-01

Radon and thoron as well as their short-lived progenies are decay products of the radium and thorium series decays. They are the most important radionuclide elements with respect to public exposure. To utilize the semiconductor pixel radiation Timepix chip for the measurement of active and real-time alpha particles from radon, thoron and their progenies, it is necessary to check the registration and visualization of the chip. An energy check for radon, thoron and their progenies, as well as for (241)Am and(210)Po sources, was performed using the radon and thoron chambers at NIRS (National Institute of Radiological Sciences). The check found an energy resolution of 200 keV with a 14% efficiency as well as a linear dependency between the channel number (cluster volume) and the energy. The coefficient of determination r(2) of 0.99 for the range of 5 to 9 MeV was calculated. In addition, an offset for specific Timepix configurations between pre-calibration for low energy from 6 to 60 keV, and the actual calibration for alpha particles with energies from 4000 to 9000 keV, was detected. Copyright © 2015 Elsevier Ltd. All rights reserved.

Past as Prologue: Educational Psychology's Legacy and Progeny

ERIC Educational Resources Information Center

Alexander, Patricia A.

2018-01-01

On the occasion of the 125th anniversary of the American Psychological Association, the legacies and progenies of the discipline of educational psychology are explored. To capture those legacies, transformational and influential contributions by educational psychologists to schools and society are described as key themes. Those themes entail: the…

Study of indoor radon and thoron progeny levels in surrounding areas of Nalbari, Assam, India

NASA Astrophysics Data System (ADS)

Deka, P. C.; Sarma, H.; Sarkar, Subir; Goswami, T. D.; Sarma, B. K.

2009-07-01

With the growing understanding of the role of radon and its daughter products as major sources of radiation exposure, the importance of large number of estimation of radon concentration in various parts of the country is realized. Inhalation of radon, thoron and their decay products is the major source of the total radioactive dose received by the human population from natural radiation. The indoor radon and thoron progeny levels in Nalbari area of Assam are studied by using the LR-115 (type II) Solid State Nuclear Track Detector in Plastic Twin Chamber dosimeter. Radon and thoron progeny levels in different types of dwellings for one full calendar year are presented in this paper. For Assam Type (A.T.) houses, indoor radon progeny concentrations vary from 0.17 to 0.64 mWL with an annual geometric mean of 0.27 mWL and that for Reinforced Cement Concrete (R.C.C.) houses vary from 0.22 mWL to 0.60 mWL with the annual geometric mean of 0.37 mWL. The thoron progeny levels in A.T. houses also vary from 0.01 to of 0.05 mWL with an annual geometric mean of 0.02 mWL and that for R.C.C. houses vary from 0.02 to 0.08 mWL with the annual geometric mean of 0.04 mWL.

Feral rice from introgression of weedy rice genes into transgenic herbicide-resistant hybrid-rice progeny.

PubMed

Zhang, Jingxu; Kang, Ye; Valverde, Bernal E; Dai, Weimin; Song, Xiaoling; Qiang, Sheng

2018-06-05

Pollen-mediated herbicide-resistance transgene flow occurs bidirectionally between transgenic cultivated rice and weedy rice. The potential risk of weedy traits introgressing into hybrid rice is underestimated and poorly understood. Two of each glufosinate-resistant transgenic rice varieties and hybrid rice (F1) and their succeeding generations (F2-F4) were planted for three years in weedy-rice-free field plots adjacent to experimental weedy-rice fields. Weedy-rice-like (feral) plants, both glufosinate-resistant and with red-pericarp seed, were initially found only among the F3 generations of the two glufosinate-resistant transgenic hybrid rice. The composite fitness (an index based on eight productivity and weediness traits) of the feral progeny was significantly higher than that of glufosinate-resistant transgenic hybrid rice (the original female parent of feral progeny) under common monoculture garden conditions. Hybrid rice progeny segregated into individuals of variable height and extended flowering. Hybrid rice F2 generations had higher outcrossing rates by pollen reception (0.96%-1.65%) than their progenitors (0.07%-0.98%). Herbicide-resistant weedy rice can rapidly arise by pollen-mediated gene flow from weedy to transgenic hybrid rice. Their segregating pollen-receptive progeny pose greater agro-ecological risk than transgenic varieties. The safety assessment and management regulations for transgenic hybrid rice should take into account the risk of bidirectional gene flow.

Single Low-Dose Ionizing Radiation Induces Genotoxicity in Adult Zebrafish and its Non-Irradiated Progeny.

PubMed

Lemos, J; Neuparth, T; Trigo, M; Costa, P; Vieira, D; Cunha, L; Ponte, F; Costa, P S; Metello, L F; Carvalho, A P

2017-02-01

This study investigated to what extent a single exposure to low doses of ionizing radiation can induce genotoxic damage in irradiated adult zebrafish (Danio rerio) and its non-irradiated F1 progeny. Four groups of adult zebrafish were irradiated with a single dose of X-rays at 0 (control), 100, 500 and 1000 mGy, respectively, and couples of each group were allowed to reproduce following irradiation. Blood of parental fish and whole-body offspring were analysed by the comet assay for detection of DNA damage. The level of DNA damage in irradiated parental fish increased in a radiation dose-dependent manner at day 1 post-irradiation, but returned to the control level thereafter. The level of DNA damage in the progeny was directly correlated with the parental irradiation dose. Results highlight the genotoxic risk of a single exposure to low-dose ionizing radiation in irradiated individuals and also in its non-irradiated progeny.

Identification of QTL for Early Vigor and Stay-Green Conferring Tolerance to Drought in Two Connected Advanced Backcross Populations in Tropical Maize (Zea mays L.)

PubMed Central

Trachsel, Samuel; Sun, Dapeng; SanVicente, Felix M.; Zheng, Hongjian; Atlin, Gary N.; Suarez, Edgar Antonio; Babu, Raman; Zhang, Xuecai

2016-01-01

We aimed to identify quantitative trait loci (QTL) for secondary traits related to grain yield (GY) in two BC1F2:3 backcross populations (LPSpop and DTPpop) under well-watered (4 environments; WW) and drought stressed (6; DS) conditions to facilitate breeding efforts towards drought tolerant maize. GY reached 5.6 and 5.8 t/ha under WW in the LPSpop and the DTPpop, respectively. Under DS, grain yield was reduced by 65% (LPSpop) to 59% (DTPpop) relative to WW. GY was strongly associated with the normalized vegetative index (NDVI; r ranging from 0.61 to 0.96) across environmental conditions and with an early flowering under drought stressed conditions (r ranging from -0.18 to -0.25) indicative of the importance of early vigor and drought escape for GY. Out of the 105 detected QTL, 53 were overdominant indicative of strong heterosis. For 14 out of 18 detected vigor QTL, as well as for eight flowering time QTL the trait increasing allele was derived from CML491. Collocations of early vigor QTL with QTL for stay green (bin 2.02, WW, LPSpop; 2.07, DS, DTPpop), the number of ears per plant (bins 2.02, 2.05, WW, LPSpop; 5.02, DS, LPSpop) and GY (bin 2.07, WW, DTPpop; 5.04, WW, LPSpop), reinforce the importance of the observed correlations. LOD scores for early vigor QTL in these bins ranged from 2.2 to 11.25 explaining 4.6 (additivity: +0.28) to 19.9% (additivity: +0.49) of the observed phenotypic variance. A strong flowering QTL was detected in bin 2.06 across populations and environmental conditions explaining 26–31.3% of the observed phenotypic variation (LOD: 13–17; additivity: 0.1–0.6d). Improving drought tolerance while at the same time maintaining yield potential could be achieved by combining alleles conferring early vigor from the recurrent parent with alleles advancing flowering from the donor. Additionally bin 8.06 (DTPpop) harbored a QTL for GY under WW (additivity: 0.27 t/ha) and DS (additivity: 0.58 t/ha). R2 ranged from 0 (DTPpop, WW) to 26.54% (LPSpop

Vesicular Transport of Progeny Parvovirus Particles through ER and Golgi Regulates Maturation and Cytolysis

PubMed Central

Bär, Séverine; Rommelaere, Jean; Nüesch, Jürg P. F.

2013-01-01

Progeny particles of non-enveloped lytic parvoviruses were previously shown to be actively transported to the cell periphery through vesicles in a gelsolin-dependent manner. This process involves rearrangement and destruction of actin filaments, while microtubules become protected throughout the infection. Here the focus is on the intracellular egress pathway, as well as its impact on the properties and release of progeny virions. By colocalization with cellular marker proteins and specific modulation of the pathways through over-expression of variant effector genes transduced by recombinant adeno-associated virus vectors, we show that progeny PV particles become engulfed into COPII-vesicles in the endoplasmic reticulum (ER) and are transported through the Golgi to the plasma membrane. Besides known factors like sar1, sec24, rab1, the ERM family proteins, radixin and moesin play (an) essential role(s) in the formation/loading and targeting of virus-containing COPII-vesicles. These proteins also contribute to the transport through ER and Golgi of the well described analogue of cellular proteins, the secreted Gaussia luciferase in absence of virus infection. It is therefore likely that radixin and moesin also serve for a more general function in cellular exocytosis. Finally, parvovirus egress via ER and Golgi appears to be necessary for virions to gain full infectivity through post-assembly modifications (e.g. phosphorylation). While not being absolutely required for cytolysis and progeny virus release, vesicular transport of parvoviruses through ER and Golgi significantly accelerates these processes pointing to a regulatory role of this transport pathway. PMID:24068925

Nutritional supplement chromium picolinate generates chromosomal aberrations and impedes progeny development in Drosophila melanogaster.

PubMed

Stallings, Dontarie M; Hepburn, Dion D D; Hannah, Meredith; Vincent, John B; O'Donnell, Janis

2006-11-07

Chromium picolinate, [Cr(pic)(3)], is a popular nutritional supplement found in a variety of consumer products. Despite its popularity, safety concerns over its use have arisen. The supplement has been shown to generate clastogenic damage, mitochondrial damage, oxidative damage, and mutagenic effects in cultured cells and oxidative DNA damage and lipid peroxidation in rats. Recently [Cr(pic)(3)] has been demonstrated to generate heritable genetic change and delays in progeny development in Drosophila melanogaster. Based on the damage to chromosomes of cultured cells and of animal models, similar chromosome damage appeared to be a likely source of the mutagenic effects of the supplement in Drosophila. The current three-part study examines the effects of several chromium-containing supplements and their components on hatching and eclosion rates and success of development of first generation progeny of adult Drosophila fed food containing these compounds. It further examines the effects of the compounds on longevity of virgin male and female adults. Finally, the chromosomes in the salivary glands of Drosophila late in the third instar larval stage, which were the progeny of Drosophila whose diets were supplemented with nutritional levels of [Cr(pic)(3)], are shown to contain on average over one chromosomal aberration per two identifiable chromosomal arms. No aberrations were observed in chromosomes of progeny of untreated flies. The results suggest that human consumption of the supplement should be a matter of concern and continued investigation to provide insight into the requirements of chromium-containing supplements to give rise to genotoxic effects.

Vesicular transport of progeny parvovirus particles through ER and Golgi regulates maturation and cytolysis.

PubMed

Bär, Séverine; Rommelaere, Jean; Nüesch, Jürg P F

2013-09-01

Progeny particles of non-enveloped lytic parvoviruses were previously shown to be actively transported to the cell periphery through vesicles in a gelsolin-dependent manner. This process involves rearrangement and destruction of actin filaments, while microtubules become protected throughout the infection. Here the focus is on the intracellular egress pathway, as well as its impact on the properties and release of progeny virions. By colocalization with cellular marker proteins and specific modulation of the pathways through over-expression of variant effector genes transduced by recombinant adeno-associated virus vectors, we show that progeny PV particles become engulfed into COPII-vesicles in the endoplasmic reticulum (ER) and are transported through the Golgi to the plasma membrane. Besides known factors like sar1, sec24, rab1, the ERM family proteins, radixin and moesin play (an) essential role(s) in the formation/loading and targeting of virus-containing COPII-vesicles. These proteins also contribute to the transport through ER and Golgi of the well described analogue of cellular proteins, the secreted Gaussia luciferase in absence of virus infection. It is therefore likely that radixin and moesin also serve for a more general function in cellular exocytosis. Finally, parvovirus egress via ER and Golgi appears to be necessary for virions to gain full infectivity through post-assembly modifications (e.g. phosphorylation). While not being absolutely required for cytolysis and progeny virus release, vesicular transport of parvoviruses through ER and Golgi significantly accelerates these processes pointing to a regulatory role of this transport pathway.

Measurements of radon and thoron progeny concentrations in dwellings of Tehri Garhwal, India, using LR-115 deposition-based DTPS/DRPS technique.

PubMed

Prasad, Mukesh; Rawat, Mukesh; Dangwal, Anoop; Yadav, Manjulata; Gusain, G S; Mishra, Rosaline; Ramola, R C

2015-11-01

This paper presents the values of radon and thoron progeny concentrations for different seasons in the dwellings of Tehri Garhwal, India. The measurements have been carried out using LR-115 solid-state nuclear track detector-based passive time-integrated direct thoron progeny sensor/direct radon progeny sensor technique. In summer, the radon and thoron progeny have been found to vary from 5.7±0.8 to 153.2±4.3 Bq m(-3) with an average of 37.6 Bq m(-3) and 0.3±0.06 to 3.2±0.19 Bq m(-3) with an average of 1.3 Bq m(-3), respectively. In the rainy season, the radon and thoron progeny have been found to vary from 3.2±0.6 to 120±3.7 Bq m(-3) with an average of 58.2 Bq m(-3) and 0.2±0.05 to 11.3±0.37 Bq m(-3) with an average of 3.4 Bq m(-3), respectively. In autumn, the radon and thoron progeny have been found to vary from 4.1±0.7 to 374.4±6.7 Bq m(-3) with an average of 95.6 Bq m(-3) and from 0.3±0.06 to 30.5±0.60 Bq m(-3) with an average of 6.6 Bq m(-3), respectively. In winter, the radon and thoron progeny have been found to vary from 9.8±1.1 to 188.9±4.8 Bq m(-3) with an average of 70.7 Bq m(-3) and 0.1±0.03 to 7.5±0.30 Bq m(-3) with an average of 2.3 Bq m(-3), respectively. It has been observed that the average value of radon and thoron progeny concentrations is maximum for autumn and minimum for summer seasons. The seasonal variations in radon and thoron progeny concentrations in different houses are discussed in detail. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Prevention of inclusion body hepatitis/hydropericardium syndrome in progeny chickens by vaccination of breeders with fowl adenovirus and chicken anemia virus.

PubMed

Toro, H; González, C; Cerda, L; Morales, M A; Dooner, P; Salamero, M

2002-01-01

The hypothesis that an effective protection of progeny chickens against inclusion body hepatitis/hydropericardium syndrome (IBH/HP) can be achieved by dual vaccination of breeders with fowl adenovirus (FAV) serotype 4 and chicken anemia virus (CAV) was tested. Thus, 17-wk-old brown leghorn pullet groups were vaccinated by different schemes including single FAV (inactivated), single CAV (attenuated), FAV and CAV dually, or were not vaccinated (controls). Subsequent progenies of these breeders were challenged with the virulent strains FAV-341 and CAV-10343 following three strategies: 1) FAV-341 intramuscularly (i.m.) at day 10 of age (only FAV-vaccinated and control progenies); 2) FAV + CAV i.m. simultaneously at day 10 of age (all progenies); 3) CAV i.m. at day 1 and FAV orally at day 10 of age (all progenies). The induction of IBH/HP in these progenies was evaluated throughout a 10-day period. Both breeder groups vaccinated against FAV and those vaccinated against CAV increased virus neutralizing specific antibodies. Challenge strategy 1 showed 26.6% mortality in control progeny chickens and 13.3% in the progeny of FAV-vaccinated breeders. Presence of lesions in the liver of these groups showed no significant differences (P > 0.05), suggesting a discreet protective effect of the vaccine. Challenge strategy 2 showed 29.4% mortality in controls and 94% of chickens showed hepatic inclusion bodies (HIB). Single CAV vaccination of breeders did not demonstrate a beneficial effect, with both mortality and liver lesions resembling the nonvaccinated controls. FAV vaccination of breeders significantly reduced both mortality (7.4%) and liver lesions (26% HIB) (P < 0.05), providing protection against this challenge strategy. Dual vaccination of breeders with FAV and CAV proved to be necessary to achieve maximum protection of the progeny (no mortality and 7% HIB). Challenge strategy 3 produced no mortality but consistent liver damage in controls (96% HIB). In this case, both

Inherited XX sex reversal originating from wild medaka populations.

PubMed

Shinomiya, A; Otake, H; Hamaguchi, S; Sakaizumi, M

2010-11-01

The teleost fish, medaka (Oryzias latipes), has an XX/XY sex-determining mechanism. A Y-linked DM domain gene, DMY, has been isolated by positional cloning as the sex-determining gene in this species. Previously, we conducted a field survey of genotypic sex and found that approximately 1% of wild medaka are sex-reversed (XX males and XY females). Here, we performed genetic analyses of nine spontaneous XX sex-reversed males to elucidate its genetic basis. In all cases, the F(1) progeny were all females, whereas XX males reappeared in the backcross (BC) progeny, suggesting that XX sex reversal is a recessive trait. Although the incidences of sex reversal in the BC progeny were mostly low, 40% were males derived from one XX male. We performed linkage analysis using 55 BC males and located a single major factor, sda-1 (sex-determining autosomal factor-1), controlling sex reversal in an autosomal linkage group. Thus, genes involved in the sex-determining pathway can be isolated from spontaneous mutants in wild populations.

Do transgenesis and marker-assisted backcross breeding produce substantially equivalent plants? A comparative study of transgenic and backcross rice carrying bacterial blight resistant gene Xa21.

PubMed

Gao, Lifen; Cao, Yinghao; Xia, Zhihui; Jiang, Guanghuai; Liu, Guozhen; Zhang, Weixiong; Zhai, Wenxue

2013-10-29

The potential impact of genetically modified (GM) plants on human health has attracted much attention worldwide, and the issue remains controversial. This is in sharp contrast to the broad acceptance of plants produced by breeding through Marker Assisted Backcrossing (MAB). Focusing on transcriptome variation and perturbation to signaling pathways, we assessed the molecular and biological aspects of substantial equivalence, a general principle for food safety endorsed by the Food and Agricultural Organization and the World Health Organization, between a transgenic crop and a plant from MAB breeding. We compared a transgenic rice line (DXT) and a MAB rice line (DXB), both of which contain the gene Xa21 providing resistance to bacterial leaf blight. By using Next-Generation sequencing data of DXT, DXB and their parental line (D62B), we compared the transcriptome variation of DXT and DXB. Remarkably, DXT had 43% fewer differentially expressed genes (DEGs) than DXB. The genes exclusively expressed in DXT and in DXB have pathogen and stress defense functions. Functional categories of DEGs in DXT were comparable to that in DXB, and seven of the eleven pathways significantly affected by transgenesis were also perturbed by MAB breeding. These results indicated that the transgenic rice and rice from MAB breeding are substantial equivalent at the transcriptome level, and paved a way for further study of transgenic rice, e.g., understanding the chemical and nutritional properties of the DEGs identified in the current study.

Do transgenesis and marker-assisted backcross breeding produce substantially equivalent plants? - A comparative study of transgenic and backcross rice carrying bacterial blight resistant gene Xa21

PubMed Central

2013-01-01

Background The potential impact of genetically modified (GM) plants on human health has attracted much attention worldwide, and the issue remains controversial. This is in sharp contrast to the broad acceptance of plants produced by breeding through Marker Assisted Backcrossing (MAB). Results Focusing on transcriptome variation and perturbation to signaling pathways, we assessed the molecular and biological aspects of substantial equivalence, a general principle for food safety endorsed by the Food and Agricultural Organization and the World Health Organization, between a transgenic crop and a plant from MAB breeding. We compared a transgenic rice line (DXT) and a MAB rice line (DXB), both of which contain the gene Xa21 providing resistance to bacterial leaf blight. By using Next-Generation sequencing data of DXT, DXB and their parental line (D62B), we compared the transcriptome variation of DXT and DXB. Remarkably, DXT had 43% fewer differentially expressed genes (DEGs) than DXB. The genes exclusively expressed in DXT and in DXB have pathogen and stress defense functions. Functional categories of DEGs in DXT were comparable to that in DXB, and seven of the eleven pathways significantly affected by transgenesis were also perturbed by MAB breeding. Conclusions These results indicated that the transgenic rice and rice from MAB breeding are substantial equivalent at the transcriptome level, and paved a way for further study of transgenic rice, e.g., understanding the chemical and nutritional properties of the DEGs identified in the current study. PMID:24165682

Hybrids between common and Antarctic minke whales are fertile and can back-cross.

PubMed

Glover, Kevin A; Kanda, Naohisa; Haug, Tore; Pastene, Luis A; Øien, Nils; Seliussen, Bjørghild B; Sørvik, Anne G E; Skaug, Hans J

2013-04-15

Minke whales are separated into two genetically distinct species: the Antarctic minke whale found in the southern hemisphere, and the common minke whale which is cosmopolitan. The common minke whale is further divided into three allopatric sub-species found in the North Pacific, southern hemisphere, and the North Atlantic. Here, we aimed to identify the genetic ancestry of a pregnant female minke whale captured in the North Atlantic in 2010, and her fetus, using data from the mtDNA control region, 11 microsatellite loci and a sex determining marker. All statistical parameters demonstrated that the mother was a hybrid displaying maternal and paternal contribution from North Atlantic common and Antarctic minke whales respectively. Her female fetus displayed greater genetic similarity to North Atlantic common minke whales than herself, strongly suggesting that the hybrid mother had paired with a North Atlantic common minke whale. This study clearly demonstrates, for the first time, that hybrids between minke whale species may be fertile, and that they can back-cross. Whether contact between these species represents a contemporary event linked with documented recent changes in the Antarctic ecosystem, or has occurred at a low frequency over many years, remains open.

Particle size distribution of the radon progeny and ambient aerosols in the Underground Tourist Route "Liczyrzepa" Mine in Kowary Adit

NASA Astrophysics Data System (ADS)

Wołoszczuk, Katarzyna; Skubacz, Krystian

2018-01-01

Central Laboratory for Radiological Protection, in cooperation with Central Mining Institute performed measurements of radon concentration in air, potential alpha energy concentration (PAEC), particle size distribution of the radon progeny and ambient aerosols in the Underground Tourist-Educational Route "Liczyrzepa" Mine in Kowary Adit. A research study was developed to investigate the appropriate dose conversion factors for short-lived radon progeny. The particle size distribution of radon progeny was determined using Radon Progeny Particle Size Spectrometer (RPPSS). The device allows to receive the distribution of PAEC in the particle size range from 0.6 nm to 2494 nm, based on their activity measured on 8 stages composed of impaction plates or diffusion screens. The measurements of the ambient airborne particle size distribution were performed in the range from a few nanometres to about 20 micrometres using Aerodynamic Particle Sizer (APS) spectrometer and the Scanning Mobility Particle Sizer Spectrometer (SMPS).

Mapping of a gene responsible for dermatitis in NOA (Naruto Research Institute Otsuka Atrichia) mice, an animal model of allergic dermatitis.

PubMed

Natori, K; Tamari, M; Watanabe, O; Onouchi, Y; Shiomoto, Y; Kubo, S; Nakamura, Y

1999-01-01

The NOA (Naruto Research Institute Otsuka Atrichia) mouse is an animal model of allergic or atopic dermatitis, a condition characterized by ulcerative skin lesions with accumulation of mast cells and increased serum IgE. These features of the murine disease closely resemble human atopy and atopic disorders. We performed linkage analysis in NOA back-cross progeny, as a step toward identifying and isolating a gene responsible for the NOA phenotype. We crossed NOA mice with five other murine strains (C57BL/6J, IQI, C3H/HeJ, DBA/2J, and BALB/cByJ) and then bred back-cross animals. Using microsatellite markers, we scanned the entire genomes of 559 N2 offspring from the five parental strains. Linkage analysis revealed a significant association between ulcerative skin lesions and markers on murine chromosome 14. Statistical analysis indicated that the critical region was assigned to the vicinity of D14Mit236 and D14Mit160.

High-resolution mapping of D16Led-1, Gart, Gas-r, Cbr, Pcp-4, and Erg on distal mouse chromosome 16

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

Mjaatvedt, A.E.; Citron, M.P.; Reeves, R.H.

1993-08-01

More than 500 backcross progeny from four inter-subspecific backcrosses were typed for six markers on distal mouse chromosome 16. Five of these represented genes that mapped within the Sod-1 to Ets-2 interval, which was shown previously to contain the weaver (wv) gene. The map order, including previously mapped reference markers, is (cen)-D16H21S16-D16Led-1-App-Sod-1-Gart-Gas-4-Cbr-wv-Pep-4-Erg-Ets-2. This gene order recapitulates the order of the genes on human chromosome 21 where known. Two of these markers further define the region containing the weaver gene to a 3.9-cM segment between Cbr and Pcp-4. In addition, Pep-4 was localized to human chromosome 21 by the presence ofmore » a human-specific restriction fragment in WAV-17, a mouse-human somatic cell hybrid with human chromosome 31 as the only human contribution. 26 refs., 3 figs., 3 tabs.« less

Identification of steelhead and resident rainbow trout progeny in the Deschutes River, Oregon, revealed with otolith microchemistry

USGS Publications Warehouse

Zimmerman, C.E.; Reeves, G.H.

2002-01-01

Comparisons of strontium:calcium (Sr:Ca) ratios in otolith primordia and freshwater growth regions were used to identify the progeny of steelhead Oncorhynchus mykiss (anadromous rainbow trout) and resident rainbow trout in the Deschutes River, Oregon. We cultured progeny of known adult steelhead and resident rainbow trout to confirm the relationship between Sr:Ca ratios in otolith primordia and the life history of the maternal parent. The mean (??SD) Sr:Ca ratio was significantly higher in the otolith primordia of the progeny of steelhead (0.001461 ?? 0.00029; n = 100) than in those of the progeny of resident rainbow trout (0.000829 ?? 0.000012; n = 100). We used comparisons of Sr:Ca ratios in the primordia and first-summer growth regions of otoliths to determine the maternal origin of unknown O. mykiss juveniles (n = 272) collected from rearing habitats within the main-stem Deschutes River and tributary rearing habitats and thus to ascertain the relative proportion of each life history morph in each rearing habitat. Resident rainbow trout fry dominated the bi-monthly samples collected from main-stem rearing habitats between May and November 1995. Steelhead fry dominated samples collected from below waterfalls on two tributaries in 1996 and 1998.

Phenotypic characterization of the Komeda miniature rat Ishikawa, an animal model of dwarfism caused by a mutation in Prkg2.

PubMed

Tsuchida, Atsuko; Yokoi, Norihide; Namae, Misako; Fuse, Masanori; Masuyama, Taku; Sasaki, Masashi; Kawazu, Shoji; Komeda, Kajuro

2008-12-01

The Komeda miniature rat Ishikawa (KMI) is a spontaneous animal model of dwarfism caused by a mutation in Prkg2, which encodes cGMP-dependent protein kinase type II (cGKII). This strain has been maintained as a segregating inbred strain for the mutated allele mri. In this study, we characterized the phenotype of the KMI strain, particularly growth traits, craniofacial measurements, and organ weights. The homozygous mutant (mri/mri) animals were approximately 70% to 80% of the size of normal, heterozygous (mri/+) animals in regard to body length, weight, and naso-occipital length of the calvarium, and the retroperitoneal fat of mri/mri rats was reduced greatly. In addition, among progeny of the (BNxKMI-mri/mri)F1xKMI-mri/mri backcross, animals with the KMI phenotype (mri/mri) were easily distinguished from those showing the wild-type phenotype (mri/+) by using growth traits such as body length and weight. Genetic analysis revealed that all of the backcrossed progeny exhibiting the KMI phenotype were homozygous for the KMI allele in the 1.2-cM region between D14Rat5 and D14Rat80 on chromosome 14, suggesting strongly that mri acts in a completely recessive manner. The KMI strain is the first and only rat model with a confirmed mutation in Prkg2 and is a valuable model for studying dwarfism and longitudinal growth traits in humans and for functional studies of cGKII.

Phenotypic Characterization of the Komeda Miniature Rat Ishikawa, an Animal Model of Dwarfism Caused by a Mutation in Prkg2

PubMed Central

Tsuchida, Atsuko; Yokoi, Norihide; Namae, Misako; Fuse, Masanori; Masuyama, Taku; Sasaki, Masashi; Kawazu, Shoji; Komeda, Kajuro

2008-01-01

The Komeda miniature rat Ishikawa (KMI) is a spontaneous animal model of dwarfism caused by a mutation in Prkg2, which encodes cGMP-dependent protein kinase type II (cGKII). This strain has been maintained as a segregating inbred strain for the mutated allele mri. In this study, we characterized the phenotype of the KMI strain, particularly growth traits, craniofacial measurements, and organ weights. The homozygous mutant (mri/mri) animals were approximately 70% to 80% of the size of normal, heterozygous (mri/+) animals in regard to body length, weight, and naso-occipital length of the calvarium, and the retroperitoneal fat of mri/mri rats was reduced greatly. In addition, among progeny of the (BN×KMI-mri/mri)F1×KMI-mri/mri backcross, animals with the KMI phenotype (mri/mri) were easily distinguished from those showing the wild-type phenotype (mri/+) by using growth traits such as body length and weight. Genetic analysis revealed that all of the backcrossed progeny exhibiting the KMI phenotype were homozygous for the KMI allele in the 1.2-cM region between D14Rat5 and D14Rat80 on chromosome 14, suggesting strongly that mri acts in a completely recessive manner. The KMI strain is the first and only rat model with a confirmed mutation in Prkg2 and is a valuable model for studying dwarfism and longitudinal growth traits in humans and for functional studies of cGKII. PMID:19149413

Doses from beta radiation in sensitive layers of human lung and dose conversion factors due to 222Rn/220Rn progeny.

PubMed

Markovic, V M; Stevanovic, N; Nikezic, D

2011-08-01

Great deal of work has been devoted to determine doses from alpha particles emitted by (222)Rn and (220)Rn progeny. In contrast, contribution of beta particles to total dose has been neglected by most of the authors. The present work describes a study of the detriment of (222)Rn and (220)Rn progeny to the human lung due to beta particles. The dose conversion factor (DCF) was introduced to relate effective dose and exposure to radon progeny; it is defined as effective dose per unit exposure to inhaled radon or thoron progeny. Doses and DCFs were determined for beta radiation in sensitive layers of bronchi (BB) and bronchioles (bb), taking into account inhaled (222)Rn and (220)Rn progeny deposited in mucus and cilia layer. The nuclei columnar secretory and short basal cells were considered to be sensitive target layers. For dose calculation, electron-absorbed fractions (AFs) in the sensitive layers of the BB and bb regions were used. Activities in the fast and slow mucus of the BB and bb regions were obtained using the LUNGDOSE software developed earlier. Calculated DCFs due to beta radiation were 0.21 mSv/WLM for (222)Rn and 0.06 mSv/WLM for (220)Rn progeny. In addition, the influence of Jacobi room parameters on DCFs was investigated, and it was shown that DCFs vary with these parameters by up to 50%.

White oak growth after 23 Years in a three-site provenance/progeny trial on a latitudinal gradient in Indiana

Treesearch

Yen-Ning Huang; Hao Zhang; Scott Rogers; Mark Coggeshall; Keith Woeste

2015-01-01

To increase the availability of improved, adapted white oak (Quercus alba L.) for midwestern United States landowners, we analyzed data from three 23-year-old provenance/progeny tests of 70 open-pollinated progenies from 17 provenances. Our goal was to estimate the heritability of height growth and range of adaptation and ultimately to determine...

Current advance methods for the identification of blast resistance genes in rice.

PubMed

Tanweer, Fatah A; Rafii, Mohd Y; Sijam, Kamaruzaman; Rahim, Harun A; Ahmed, Fahim; Latif, Mohammad A

2015-05-01

Rice blast caused by Magnaporthe oryzae is one of the most devastating diseases of rice around the world and crop losses due to blast are considerably high. Many blast resistant rice varieties have been developed by classical plant breeding and adopted by farmers in various rice-growing countries. However, the variability in the pathogenicity of the blast fungus according to environment made blast disease a major concern for farmers, which remains a threat to the rice industry. With the utilization of molecular techniques, plant breeders have improved rice production systems and minimized yield losses. In this article, we have summarized the current advanced molecular techniques used for controlling blast disease. With the advent of new technologies like marker-assisted selection, molecular mapping, map-based cloning, marker-assisted backcrossing and allele mining, breeders have identified more than 100 Pi loci and 350 QTL in rice genome responsible for blast disease. These Pi genes and QTLs can be introgressed into a blast-susceptible cultivar through marker-assisted backcross breeding. These molecular techniques provide timesaving, environment friendly and labour-cost-saving ways to control blast disease. The knowledge of host-plant interactions in the frame of blast disease will lead to develop resistant varieties in the future. Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.

Did backcrossing contribute to the origin of hybrid edible bananas?

PubMed Central

De Langhe, Edmond; Hřibová, Eva; Carpentier, Sebastien; Doležel, Jaroslav; Swennen, Rony

2010-01-01

Background Bananas and plantains (Musa spp.) provide a staple food for many millions of people living in the humid tropics. The cultivated varieties (cultivars) are seedless parthenocarpic clones of which the origin remains unclear. Many are believed to be diploid and polyploid hybrids involving the A genome diploid M. acuminata and the B genome M. balbisiana, with the hybrid genomes consisting of a simple combination of the parental ones. Thus the genomic constitution of the diploids has been classified as AB, and that of the triploids as AAB or ABB. However, the morphology of many accessions is biased towards either the A or B phenotype and does not conform to predictions based on these genomic formulae. Scope On the basis of published cytotypes (mitochondrial and chloroplast genomes), we speculate here that the hybrid banana genomes are unbalanced with respect to the parental ones, and/or that inter-genome translocation chromosomes are relatively common. We hypothesize that the evolution under domestication of cultivated banana hybrids is more likely to have passed through an intermediate hybrid, which was then involved in a variety of backcrossing events. We present experimental data supporting our hypothesis and we propose a set of experimental approaches to test it, thereby indicating other possibilities for explaining some of the unbalanced genome expressions. Progress in this area would not only throw more light on the origin of one of the most important crops, but provide data of general relevance for the evolution under domestication of many other important clonal crops. At the same time, a complex origin of the cultivated banana hybrids would imply a reconsideration of current breeding strategies. PMID:20858591

Epstein-Barr Virus BKRF4 Gene Product Is Required for Efficient Progeny Production.

PubMed

Masud, H M Abdullah Al; Watanabe, Takahiro; Yoshida, Masahiro; Sato, Yoshitaka; Goshima, Fumi; Kimura, Hiroshi; Murata, Takayuki

2017-12-01

Epstein-Barr virus (EBV), a member of human gammaherpesvirus, infects mainly B cells. EBV has two alternative life cycles, latent and lytic, and is reactivated occasionally from the latent stage to the lytic cycle. To combat EBV-associated disorders, understanding the molecular mechanisms of the EBV lytic replication cycle is also important. Here, we focused on an EBV lytic gene, BKRF4. Using our anti-BKRF4 antibody, we revealed that the BKRF4 gene product is expressed during the lytic cycle with late kinetics. To characterize the role of BKRF4, we constructed BKRF4-knockout mutants using the bacterial artificial chromosome (BAC) and CRISPR/Cas9 systems. Although disruption of the BKRF4 gene had almost no effect on viral protein expression and DNA synthesis, it significantly decreased progeny virion levels in HEK293 and Akata cells. Furthermore, we show that BKRF4 is involved not only in production of progeny virions but also in increasing the infectivity of the virus particles. Immunoprecipitation assays revealed that BKRF4 interacted with a virion protein, BGLF2. We showed that the C-terminal region of BKRF4 was critical for this interaction and for efficient progeny production. Immunofluorescence analysis revealed that BKRF4 partially colocalized with BGLF2 in the nucleus and perinuclear region. Finally, we showed that BKRF4 is a phosphorylated, possible tegument protein and that the EBV protein kinase BGLF4 may be important for this phosphorylation. Taken together, our data suggest that BKRF4 is involved in the production of infectious virions. IMPORTANCE Although the latent genes of EBV have been studied extensively, the lytic genes are less well characterized. This study focused on one such lytic gene, BKRF4, which is conserved only among gammaherpesviruses (ORF45 of Kaposi's sarcoma-associated herpesvirus or murine herpesvirus 68). After preparing the BKRF4 knockout virus using B95-8 EBV-BAC, we demonstrated that the BKRF4 gene was involved in infectious

Genotype × Environment Interactions of Yield Traits in Backcross Introgression Lines Derived from Oryza sativa cv. Swarna/Oryza nivara

PubMed Central

Balakrishnan, Divya; Subrahmanyam, Desiraju; Badri, Jyothi; Raju, Addanki Krishnam; Rao, Yadavalli Venkateswara; Beerelli, Kavitha; Mesapogu, Sukumar; Surapaneni, Malathi; Ponnuswamy, Revathi; Padmavathi, G.; Babu, V. Ravindra; Neelamraju, Sarla

2016-01-01

Advanced backcross introgression lines (BILs) developed from crosses of Oryza sativa var. Swarna/O. nivara accessions were grown and evaluated for yield and related traits. Trials were conducted for consecutive three seasons in field conditions in a randomized complete block design with three replications. Data on yield traits under irrigated conditions were analyzed using the Additive Main Effect and Multiplicative Interaction (AMMI), Genotype and Genotype × Environment Interaction (GGE) and modified rank-sum statistic (YSi) for yield stability. BILs viz., G3 (14S) and G6 (166S) showed yield stability across the seasons along with high mean yield performance. G3 is early in flowering with high yield and has good grain quality and medium height, hence could be recommended for most of the irrigated locations. G6 is a late duration genotype, with strong culm strength, high grain number and panicle weight. G6 has higher yield and stability than Swarna but has Swarna grain type. Among the varieties tested DRRDhan 40 and recurrent parent Swarna showed stability for yield traits across the seasons. The component traits thousand grain weight, panicle weight, panicle length, grain number and plant height explained highest genotypic percentage over environment and interaction factors and can be prioritized to dissect stable QTLs/ genes. These lines were genotyped using microsatellite markers covering the entire rice genome and also using a set of markers linked to previously reported yield QTLs. It was observed that wild derived lines with more than 70% of recurrent parent genome were stable and showed enhanced yield levels compared to genotypes with higher donor genome introgressions. PMID:27807437

Analysis of the New Zealand Black contribution to lupus-like renal disease

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

Drake, C.G.; Rozzo, S.J.; Hirschfeld, H.F.

1995-03-01

F{sub 1} progeny of New Zealand Black (NZB) and New Zealand White (NZW) mice spontaneously develop an autoimmune process remarkably similar to human systemic lupus erythematosus. Previous studies have implicated major genetic contributions from the NZW MHC and from a dominant NZB gene on chromosome 4. To identify additional NZB contributions to lupus-like disease, (NZB x SM/J)F{sub 1} x NZW backcross mice were followed for the development of severe renal disease and were comprehensively genotyped. Despite a 50% incidence of disease significant associations between the presence of the NZB genotype and disease were noted on chromosomes 1, 4, 7, 10,more » 13, and 19. The data indicated that multiple NZB genes, in different combinations, contribute to severe renal disease, and that no single gene is required. To further investigate this NZB contribution, NZB x SM/J (NXSM) recombinant inbred (RI) strains were crossed with NZW mice, and F{sub 1} progeny were analyzed for the presence of lupus-like renal disease. Interestingly, nearly all of the (RI x NZW)F{sub 1} cohorts studies expressed some level of disease. Five RI strains generated a high incidence of disease, similar to (NZB x NZW)F{sub 1} mice, and nearly one-half of the cohorts developed disease at intermediate levels. Only two cohorts demonstrated very little disease, supporting the conclusion that multiple genes are capable of disease induction. Experiments correlating the genotypes of these RI strains with their ability to generate disease revealed that none of the disease-associated loci defined by the backcross analysis were present in all five RI strains that generated disease at high levels. Overall, both the backcross data and RI analysis provide additional support for the genetic complexity of lupus nephritis and uphold the conclusion that heterogeneous combinations of contributing NZB genes seem to operate in a threshold manner to generate the disease phenotype. 31 refs., 3 figs., 2 tabs.« less

A review of lung-to-blood absorption rates for radon progeny.

PubMed

Marsh, J W; Bailey, M R

2013-12-01

The International Commission on Radiological Protection (ICRP) Publication 66 Human Respiratory Tract Model (HRTM) treats clearance of materials from the respiratory tract as a competitive process between absorption into blood and particle transport to the alimentary tract and lymphatics. The ICRP recommended default absorption rates for lead and polonium (Type M) in ICRP Publication 71 but stated that the values were not appropriate for short-lived radon progeny. This paper reviews and evaluates published data from volunteer and laboratory animal experiments to estimate the HRTM absorption parameter values for short-lived radon progeny. Animal studies showed that lead ions have two phases of absorption: ∼10 % absorbed with a half-time of ∼15 min, the rest with a half-time of ∼10 h. The studies also indicated that some of the lead ions were bound to respiratory tract components. Bound fractions, f(b), for lead were estimated from volunteer and animal studies and ranged from 0.2 to 0.8. Based on the evaluations of published data, the following HRTM absorption parameter values were derived for lead as a decay product of radon: f(r) = 0.1, s(r) = 100 d(-1), s(s) = 1.7 d(-1), f(b) = 0.5 and s(b) = 1.7 d(-1). Effective doses calculated assuming these absorption parameter values instead of a single absorption half-time of 10 h with no binding (as has generally been assumed) are only a few per cent higher. However, as there is some conflicting evidence on the absorption kinetics for radon progeny, dose calculations have been carried out for different sets of absorption parameter values derived from different studies. The results of these calculations are discussed.

SmartGrain: high-throughput phenotyping software for measuring seed shape through image analysis.

PubMed

Tanabata, Takanari; Shibaya, Taeko; Hori, Kiyosumi; Ebana, Kaworu; Yano, Masahiro

2012-12-01

Seed shape and size are among the most important agronomic traits because they affect yield and market price. To obtain accurate seed size data, a large number of measurements are needed because there is little difference in size among seeds from one plant. To promote genetic analysis and selection for seed shape in plant breeding, efficient, reliable, high-throughput seed phenotyping methods are required. We developed SmartGrain software for high-throughput measurement of seed shape. This software uses a new image analysis method to reduce the time taken in the preparation of seeds and in image capture. Outlines of seeds are automatically recognized from digital images, and several shape parameters, such as seed length, width, area, and perimeter length, are calculated. To validate the software, we performed a quantitative trait locus (QTL) analysis for rice (Oryza sativa) seed shape using backcrossed inbred lines derived from a cross between japonica cultivars Koshihikari and Nipponbare, which showed small differences in seed shape. SmartGrain removed areas of awns and pedicels automatically, and several QTLs were detected for six shape parameters. The allelic effect of a QTL for seed length detected on chromosome 11 was confirmed in advanced backcross progeny; the cv Nipponbare allele increased seed length and, thus, seed weight. High-throughput measurement with SmartGrain reduced sampling error and made it possible to distinguish between lines with small differences in seed shape. SmartGrain could accurately recognize seed not only of rice but also of several other species, including Arabidopsis (Arabidopsis thaliana). The software is free to researchers.

STUDY OF RADIATION EXPOSURE DUE TO RADON, THORON AND PROGENY IN THE INDOOR ENVIRONMENT OF YAMUNA AND TONS VALLEYS OF GARHWAL HIMALAYA.

PubMed

Prasad, Mukesh; Rawat, Mukesh; Dangwal, Anoop; Prasad, Ganesh; Mishra, Rosaline; Ramola, R C

2016-10-01

Long-term measurements of indoor radon, thoron and their progeny concentrations have been carried out in dwellings of Yamuna and Tons Valleys of Uttarkashi, Garhwal Himalaya to investigate the health risk associated with inhalation of radon, thoron and progeny. The experimentally determined values of radon, thoron and progeny concentrations were used to estimate the annual inhalation doses and annual effective doses. The annual inhalation dose has been found to vary from 0.8 to 3.9 mSv y -1 with an average of 1.8 mSv y -1 The annual effective dose from the exposure to radon and its progeny in the study area has been found to vary from 0.1 to 2.4 mSv with an average of 1.2±0.6 mSv. Similarly, the annual effective dose due to thoron and its progeny has been found to vary from 0.2 to 1.5 mSv with an average of 0.6±0.4. The measurement techniques and results obtained are discussed in detail. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Radiation dose due to radon and thoron progeny inhalation in high-level natural radiation areas of Kerala, India.

PubMed

Omori, Yasutaka; Tokonami, Shinji; Sahoo, Sarata Kumar; Ishikawa, Tetsuo; Sorimachi, Atsuyuki; Hosoda, Masahiro; Kudo, Hiromi; Pornnumpa, Chanis; Nair, Raghu Ram K; Jayalekshmi, Padmavaty Amma; Sebastian, Paul; Akiba, Suminori

2017-03-20

In order to evaluate internal exposure to radon and thoron, concentrations for radon, thoron, and thoron progeny were measured for 259 dwellings located in high background radiation areas (HBRAs, outdoor external dose: 3-5 mGy y -1 ) and low background radiation areas (control areas, outdoor external dose: 1 mGy y -1 ) in Karunagappally Taluk, Kerala, India. The measurements were conducted using passive-type radon-thoron detectors and thoron progeny detectors over two six-month measurement periods from June 2010 to June 2011. The results showed no major differences in radon and thoron progeny concentrations between the HBRAs and the control areas. The geometric mean of the annual effective dose due to radon and thoron was calculated as 0.10 and 0.44 mSv, respectively. The doses were small, but not negligible compared with the external dose in the two areas.

Study on the influence of CR-39 detector size on radon progeny detection in indoor environments

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

Pereira, L. A.; Hadler, J. C.; Lixandrão F, A. L.

It is well known that radon daughters up to {sup 214}Po are the real contaminants to be considered in case of indoor radon contamination. Assemblies consisting of 6 circular bare sheets of CR-39, a nuclear track detector, with radius varying from 0.15 to 1.2 cm were exposed far from any material surface for periods of approximately 6 months in 13 different indoor rooms (7 workplaces and 6 dwellings), where ventilation was moderate or poor. It was observed that track density was as greater as smaller was the detector radius. Track density data were fitted using an equation deduced based onmore » the assumption that the behavior of radon and its progeny in the air was described by Fick's Law, i.e., when the main mechanism of transport of radon progeny in the air is diffusion. As many people spend great part of their time in closed or poorly ventilated environments, the confirmation they present equilibrium between radon and its progeny is an interesting start for dosimetric calculations concerning this contamination.« less

Study on the influence of CR-39 detector size on radon progeny detection in indoor environments

NASA Astrophysics Data System (ADS)

Pereira, L. A.; Hadler, J. C.; Lixandrão F., A. L.; Guedes, S.; Takizawa, R. H.

2014-11-01

It is well known that radon daughters up to 214Po are the real contaminants to be considered in case of indoor radon contamination. Assemblies consisting of 6 circular bare sheets of CR-39, a nuclear track detector, with radius varying from 0.15 to 1.2 cm were exposed far from any material surface for periods of approximately 6 months in 13 different indoor rooms (7 workplaces and 6 dwellings), where ventilation was moderate or poor. It was observed that track density was as greater as smaller was the detector radius. Track density data were fitted using an equation deduced based on the assumption that the behavior of radon and its progeny in the air was described by Fick's Law, i.e., when the main mechanism of transport of radon progeny in the air is diffusion. As many people spend great part of their time in closed or poorly ventilated environments, the confirmation they present equilibrium between radon and its progeny is an interesting start for dosimetric calculations concerning this contamination.

No significant level of inheritable interchromosomal aberrations in the progeny of bystander primary human fibroblasts after alpha particle irradiation

NASA Astrophysics Data System (ADS)

Hu, Burong; Zhu, Jiayun; Zhou, Hongning; Hei, Tom K.

2013-02-01

A major concern for bystander effects is the probability that normal healthy cells adjacent to the irradiated cells become genomically unstable and undergo further carcinogenesis after therapeutic irradiation or space mission where astronauts are exposed to low dose of heavy ions. Genomic instability is a hallmark of cancer cells. In the present study, two irradiation protocols were performed in order to ensure pure populations of bystander cells and the genomic instability in their progeny were investigated. After irradiation, chromosomal aberrations of cells were analyzed at designated time points using G2 phase premature chromosome condensation (G2-PCC) coupled with Giemsa staining and with multiplex fluorescent in situ hybridization (mFISH). Our Giemsa staining assay demonstrated that elevated yields of chromatid breaks were induced in the progeny of pure bystander primary fibroblasts up to 20 days after irradiation. mFISH assay showed no significant level of inheritable interchromosomal aberrations were induced in the progeny of the bystander cell groups, while the fractions of gross aberrations (chromatid breaks or chromosomal breaks) significantly increased in some bystander cell groups. These results suggest that genomic instability occurred in the progeny of the irradiation associated bystander normal fibroblasts exclude the inheritable interchromosomal aberration.

No significant level of inheritable interchromosomal aberrations in the progeny of bystander primary human fibroblast after alpha particle irradiation.

PubMed

Hu, Burong; Zhu, Jiayun; Zhou, Hongning; Hei, Tom K

2013-02-01

A major concern for bystander effects is the probability that normal healthy cells adjacent to the irradiated cells become genomically unstable and undergo further carcinogenesis after therapeutic irradiation or space mission where astronauts are exposed to low dose of heavy ions. Genomic instability is a hallmark of cancer cells. In the present study, two irradiation protocols were performed in order to ensure pure populations of bystander cells and the genomic instability in their progeny were investigated. After irradiation, chromosomal aberrations of cells were analyzed at designated time points using G 2 phase premature chromosome condensation (G 2 -PCC) coupled with Giemsa staining and with multiplex fluorescent in situ hybridization (mFISH). Our Giemsa staining assay demonstrated that elevated yields of chromatid breaks were induced in the progeny of pure bystander primary fibroblasts up to 20 days after irradiation. MFISH assay showed no significant level of inheritable interchromosomal aberrations were induced in the progeny of the bystander cell groups, while the fractions of gross aberrations (chromatid breaks or chromosomal breaks) significantly increased in some bystander cell groups. These results suggest that genomic instability occurred in the progeny of the irradiation associated bystander normal fibroblasts exclude the inheritable interchromosomal aberration.

Polyploid Titan Cells Produce Haploid and Aneuploid Progeny To Promote Stress Adaptation

PubMed Central

Gerstein, Aleeza C.; Fu, Man Shun; Mukaremera, Liliane; Li, Zhongming; Ormerod, Kate L.; Fraser, James A.; Berman, Judith

2015-01-01

ABSTRACT Cryptococcus neoformans is a major life-threatening fungal pathogen. In response to the stress of the host environment, C. neoformans produces large polyploid titan cells. Titan cell production enhances the virulence of C. neoformans, yet whether the polyploid aspect of titan cells is specifically influential remains unknown. We show that titan cells were more likely to survive and produce offspring under multiple stress conditions than typical cells and that even their normally sized daughters maintained an advantage over typical cells in continued exposure to stress. Although polyploid titan cells generated haploid daughter cell progeny upon in vitro replication under nutrient-replete conditions, titan cells treated with the antifungal drug fluconazole produced fluconazole-resistant diploid and aneuploid daughter cells. Interestingly, a single titan mother cell was capable of generating multiple types of aneuploid daughter cells. The increased survival and genomic diversity of titan cell progeny promote rapid adaptation to new or high-stress conditions. PMID:26463162

Loss of Telomeres in the Progeny of Human Lymphocytes Exposed to Energetic Heavy Ions

NASA Technical Reports Server (NTRS)

Cucinotta, F.A.; George, K.; Durante, M.

2006-01-01

We have used cross-species multi-color banding (RxFISH) combined with telomere FISH probes, to measure chromosomal aberrations in the progeny of human peripheral blood lymphocytes exposed to ionizing radiation. Accelerated iron particles (energy 1 GeV/nucleon) induced many more terminal deletions than the same dose of gamma-rays. We found that truncated chromosomes without telomeres could be transmitted for at least three cell cycles following exposure, and represented about 10% of all aberrations observed in the progeny of cells exposed to iron ions. High energy heavy ions generate the most significant health risk for human space exploration and the results suggest that telomere loss may be the leading mechanism for their high efficiency in the induction of late effects.

Evaluation of virus resistance and agronomic performance of rice cultivar ASD 16 after transfer of transgene against Rice tungro bacilliform virus by backcross breeding.

PubMed

Valarmathi, P; Kumar, G; Robin, S; Manonmani, S; Dasgupta, I; Rabindran, R

2016-08-01

Severe losses of rice yield in south and southeast Asia are caused by Rice tungro disease (RTD) induced by mixed infection of Rice tungro bacilliform virus (RTBV) and Rice tungro spherical virus (RTSV). In order to develop transgene-based resistance against RTBV, one of its genes, ORF IV, was used to generate transgenic resistance based on RNA-interference in the easily transformed rice variety Pusa Basmati-1, and the transgene was subsequently introgressed to rice variety ASD 16, a variety popular in southern India, using transgene marker-assisted selection. Here, we report the evaluation of BC3F4 and BC3F5 generation rice plants for resistance to RTBV as well as for agronomic traits under glasshouse conditions. The BC3F4 and BC3F5 generation rice plants tested showed variable levels of resistance, which was manifested by an average of twofold amelioration in height reduction, 1.5-fold decrease in the reduction in chlorophyll content, and 100- to 10,000-fold reduction in the titers of RTBV, but no reduction of RTSV titers, in three backcrossed lines when compared with the ASD 16 parent. Agronomic traits of some of the backcrossed lines recorded substantial improvements when compared with the ASD 16 parental line after inoculation by RTBV and RTSV. This work represents an important step in transferring RTD resistance to a susceptible popular rice variety, hence enhancing its yield in areas threatened by the disease.

Identification of trait-improving quantitative trait loci for grain yield components from a dent corn inbred line in an advanced backcross BC2F2 population and comparison with its F2:3 population in popcorn.

PubMed

Li, Y L; Niu, S Z; Dong, Y B; Cui, D Q; Wang, Y Z; Liu, Y Y; Wei, M G

2007-06-01

Normal maize germplasm could be used to improve the grain yield of popcorn inbreds. Our first objective was to locate genetic factors associated with trait variation and make first assessment on the efficiency of advanced backcross quantitative trait locus (AB-QTL) analysis for the identification and transfer of favorable QTL alleles for grain yield components from the dent corn inbred. A second objective was to compare the detection of QTL in the BC2F2 population with results using F(2:3) lines of the same parents. Two hundred and twenty selected BC2F2 families developed from a cross between Dan232 and an elite popcorn inbred N04 were evaluated for six grain yield components under two environments, and genotyped by means of 170 SSR markers. Using composite interval mapping (CIM), a total of 19 significant QTL were detected. Eighteen QTL had favorable alleles contributed by the dent corn parent Dan232. Sixteen of these favorable QTL alleles were not in the same or near marker intervals with QTL for popping characteristics. Six QTL were also detected in the F(2:3) population. Improved N04 could be developed from 210 and 208 families with higher grain weight per plant and/or 100-grain weight, respectively, and 35 families with the same or higher popping expansion volume than N04. In addition, near isogenic lines containing detected QTL (QTL-NILs) for grain weight per plant and/or 100-grain weight could be obtained from 12 families. Our study demonstrated that the AB-QTL method can be applied to identify and manipulate favorable QTL alleles from normal corn inbreds and combine QTL detection and popcorn breeding efficiently.

Prediction of lung cells oncogenic transformation for induced radon progeny alpha particles using sugarscape cellular automata.

PubMed

Baradaran, Samaneh; Maleknasr, Niaz; Setayeshi, Saeed; Akbari, Mohammad Esmaeil

2014-01-01

Alpha particle irradiation from radon progeny is one of the major natural sources of effective dose in the public population. Oncogenic transformation is a biological effectiveness of radon progeny alpha particle hits. The biological effects which has caused by exposure to radon, were the main result of a complex series of physical, chemical, biological and physiological interactions. The cellular and molecular mechanisms for radon-induced carcinogenesis have not been clear yet. Various biological models, including cultured cells and animals, have been found useful for studying the carcinogenesis effects of radon progeny alpha particles. In this paper, sugars cape cellular automata have been presented for computational study of complex biological effect of radon progeny alpha particles in lung bronchial airways. The model has included mechanism of DNA damage, which has been induced alpha particles hits, and then formation of transformation in the lung cells. Biomarkers were an objective measure or evaluation of normal or abnormal biological processes. In the model, the metabolism rate of infected cell has been induced alpha particles traversals, as a biomarker, has been followed to reach oncogenic transformation. The model results have successfully validated in comparison with "in vitro oncogenic transformation data" for C3H 10T1/2 cells. This model has provided an opportunity to study the cellular and molecular changes, at the various stages in radiation carcinogenesis, involving human cells. It has become well known that simulation could be used to investigate complex biomedical systems, in situations where traditional methodologies were difficult or too costly to employ.

Genetic parameters on Bali cattle progeny test population

NASA Astrophysics Data System (ADS)

Hariansyah, A. R.; Raharjo, A.; Zainuri, A.; Parwoto, Y.; Prasetiyo, D.; Prastowo, S.; Widyas, N.

2018-03-01

Bali cattle (Bos javanicus) is Indonesian indigenous cattle with having superior genetics potential on fitness traits in tropical environment and low feed quality. Bali Cattle Breeding Center Pulukan Indonesia conducted progeny test per annum in order to select bulls using offspring’s phenotype. This paper aimed to estimate the genetic parameters of yearling weight in Bali cattle progeny test populations and to observe the variation between periods in the above breeding center. Data were collected from the year of 2013 to 2014. There were four bulls (3 tests, 1 AI control) in 2013 and five bulls (4 tests, 1 AI) in 2014. Thirty breeding females were allocated per paddock per bull and allowed to mate naturally. In total 80 and 104 offspring’s records were obtained from 2013 and 2014 data, respectively. We built half-sib family model to estimate the additive genetic variance due to the sire and later estimate the breeding value (EBV) of each sire. Results showed that in 2013 the heritability (h2) for yearling weight was 0.19 while in 2014 was 0.79. In both years, tested bulls had higher EBV compared to the control bulls. The remarkable difference of heritability between years was due to the variations among bull candidates which might differ every year with regards to their origins. The fact that the EBV of tested bulls were higher than the control bulls gave us insight that despite the conservation policy and the continuous departure of Bali cattle bulls outside the Island, the population could still maintain its genetic quality.

Genetic Control of Resistance to the Sterol 14α-Demethylase Inhibitor Fungicide Prochloraz in the Cereal Eyespot Pathogen Tapesia yallundae

PubMed Central

Dyer, Paul S.; Hansen, Jacqueline; Delaney; Lucas, John A.

2000-01-01

Sexual crosses were used to determine the genetic basis of resistance to the sterol 14 α-demethylase inhibitor fungicide prochloraz in the cereal eyespot pathogen Tapesia yallundae. Three different crosses between sensitive parental strains (22-432 and 22-433 [the concentration required to inhibit growth by 50% {IG50} for each was ≤0.03 mg/liter]) and field isolates from France and New Zealand with differing levels of resistance (PR11 [IG50 = 0.5 mg/liter], PR1 [IG50 = 1.0 mg/liter], and 11-3-18 [IG50 = 2.4 mg/liter]) yielded progeny showing a bimodal distribution, with an even number of sensitive and resistant progeny. This indicated the segregation of a single major gene for resistance in each cross, which was confirmed by the use of backcrosses, crosses between F1 progeny, and control crosses between sensitive parents. However, there was also evidence of additional quantitative genetic components responsible for the increased IG50s of the more resistant isolates. A further cross was made between isolate PR11 and an F1 progeny arising from isolate 11-3-18, and this also yielded progeny which were entirely prochloraz resistant. This suggested that resistance genes were allelic in these two isolates, with resistance conferred by a gene at the same locus (or closely linked loci), despite the fact that the isolates (PR11 and 11-3-18) originated from different continents. PMID:11055899

An in vitro method for screening for the presence of thepat-2 gene in tomatoes (Lycopersicon esculentum Mill.).

PubMed

Young, T E; Juvik, J A; Sullivan, J G; Skirvin, R M

1990-01-01

Under field conditions,pat-2, the gene which conditions parthenocarpy in tomatoes, is recessive. A simple method has been devised for distinguishing the heterozygote from the two homozygotes using tissue culture. Ovaries of plants segregating for thepat-2 gene were excised and cultured on a medium containing 100 ppm gibberellic acid. After three weeks in culture, three distinct ovary sizes could be seen. It was shown, using F 3 progeny tests, that the largest ovaries corresponded to those plants homozygous for thepat-2 gene, the smallest ovaries corresponded to those plants homozygous for the wild type allele, and the intermediate sized ovaries were the heterozygotes. The ability to identify the heterozygote would greatly simplify a backcross breeding program aimed at incorporating thepat-2 gene into commercial cultivars by eliminating the need for an F 3 progeny test to determine the genotype of a plant.

Spread of Hepatitis B Viruses In Vitro Requires Extracellular Progeny and May Be Codetermined by Polarized Egress

PubMed Central

Funk, A.; Hohenberg, H.; Mhamdi, M.; Will, H.; Sirma, H.

2004-01-01

Viruses can spread by different mechanisms: via intracellular particles through cell junctions to neighboring cells or via secreted virions to adjacent or remote cells. The observation of clusters of hepadnavirus-infected cells both in vivo and in primary hepatocytes neither proves the first mechanism nor excludes the second. In order to test which mechanism, if not both, is used by hepatitis B viruses in order to spread, we used primary duck hepatocytes and duck hepatitis B virus (DHBV) as an infection model. If extracellular progeny virus alone determines spreading, neutralizing antisera or drugs blocking virus binding to hepatocytes should abolish secondary infection. In order to test this, we used DHBV envelope-specific neutralizing antisera, as well as suramin, a known inhibitor of infection. Both reagents strongly reduced hepatocellular attachment of viral particles and almost completely abolished primary infection, whereas an ongoing intracellular infection was not affected as long as no progeny virus was released. In contrast, incubation of infected primary hepatocytes with these reagents during release of progeny virus completely prevented secondary infection. Moreover, the combination of electron and immunofluorescence microscopy analyses revealed the residence of viral particles in cytoplasmic vesicles preferentially located near the basolateral membrane of infected hepatocytes. Taken together, these data strongly suggest that hepatitis B viruses mainly spread by secreted, extracellular progeny and point to polarized egress of viral particles into intercellular compartments, which restricts their diffusion and favors transmission of virus to adjacent cells. PMID:15047813

Tumor-Free Transplantation of Patient-Derived Induced Pluripotent Stem Cell Progeny for Customized Islet Regeneration.

PubMed

El Khatib, Moustafa M; Ohmine, Seiga; Jacobus, Egon J; Tonne, Jason M; Morsy, Salma G; Holditch, Sara J; Schreiber, Claire A; Uetsuka, Koji; Fusaki, Noemi; Wigle, Dennis A; Terzic, Andre; Kudva, Yogish C; Ikeda, Yasuhiro

2016-05-01

Human induced pluripotent stem cells (iPSCs) and derived progeny provide invaluable regenerative platforms, yet their clinical translation has been compromised by their biosafety concern. Here, we assessed the safety of transplanting patient-derived iPSC-generated pancreatic endoderm/progenitor cells. Transplantation of progenitors from iPSCs reprogrammed by lentiviral vectors (LV-iPSCs) led to the formation of invasive teratocarcinoma-like tumors in more than 90% of immunodeficient mice. Moreover, removal of primary tumors from LV-iPSC progeny-transplanted hosts generated secondary and metastatic tumors. Combined transgene-free (TGF) reprogramming and elimination of residual pluripotent cells by enzymatic dissociation ensured tumor-free transplantation, ultimately enabling regeneration of type 1 diabetes-specific human islet structures in vivo. The incidence of tumor formation in TGF-iPSCs was titratable, depending on the oncogenic load, with reintegration of the cMYC expressing vector abolishing tumor-free transplantation. Thus, transgene-free cMYC-independent reprogramming and elimination of residual pluripotent cells are mandatory steps in achieving transplantation of iPSC progeny for customized and safe islet regeneration in vivo. Pluripotent stem cell therapy for diabetes relies on the safety as well as the quality of derived insulin-producing cells. Data from this study highlight prominent tumorigenic risks of induced pluripotent stem cell (iPSC) products, especially when reprogrammed with integrating vectors. Two major underlying mechanisms in iPSC tumorigenicity are residual pluripotent cells and cMYC overload by vector integration. This study also demonstrated that combined transgene-free reprogramming and enzymatic dissociation allows teratoma-free transplantation of iPSC progeny in the mouse model in testing the tumorigenicity of iPSC products. Further safety assessment and improvement in iPSC specification into a mature β cell phenotype would lead to

Genetic mapping of a caffeoyl-coenzyme A 3-O-methyltransferase gene in coffee trees. Impact on chlorogenic acid content.

PubMed

Campa, C; Noirot, M; Bourgeois, M; Pervent, M; Ky, C L; Chrestin, H; Hamon, S; de Kochko, A

2003-08-01

Chlorogenic acids (CGA) are involved in the bitterness of coffee due to their decomposition in phenolic compounds during roasting. CGA mainly include caffeoyl-quinic acids (CQA), dicaffeoyl-quinic acids (diCQA) and feruloyl-quinic acids (FQA), while CQA and diCQA constitute CGA sensu stricto (CGA s.s.). In the two cultivated species Coffea canephora and Coffea arabica, CGA s.s. represents 88% and 95% of total CGA, respectively. Among all enzymes involved in CGA biosynthesis, caffeoyl-coenzyme A 3-O-methyltransferase (CCoAOMT) is not directly involved in the CGA s.s. pathway, but rather in an upstream branch leading to FQA through feruloyl-CoA. We describe how a partial cDNA corresponding to a CCoAOMT encoding gene was obtained and sequenced. Specific primers were designed and used for studying polymorphism and locating the corresponding gene on a genetic map obtained from an interspecific backcross between Coffea liberica var. Dewevrei and Coffea pseudozanguebariae. Offspring of this backcross were also evaluated for the chlorogenic acid content in their green beans. A 10% decrease was observed in backcross progenies that possess one C. pseudozanguebariae allele of the CCoAOMT gene. This suggests that CGA s.s. accumulation is dependent on the CCoAMT allele present and consequently on the activity of the encoded isoform, whereby CGA accumulation increases as the isoform activity decreases. Possible implications in coffee breeding are discussed.

Grand-paternal age and the development of autism-like symptoms in mice progeny

PubMed Central

Sampino, S; Juszczak, G R; Zacchini, F; Swiergiel, A H; Modlinski, J A; Loi, P; Ptak, G E

2014-01-01

Advanced paternal age (APA) contributes to the risk of autism spectrum disorders (ASDs) in children. In this study, we used a mouse model to investigate the effects of APA on behavioral features related to autistic syndromes (that is, social deficits, communication impairments and stereotypic/repetitive behaviors). We also examined whether such effects are transmitted across generations. To do this, males aged 15 months (APA) and 4 months (control) were bred with 4-month-old females, and the resulting offspring (F1) and their progeny (F2; conceived by 4-month-old parents) were tested for the presence and severity of ASD-like behaviors. Our results indicate that APA resulted in offspring that displayed distinctive symptoms of ASD. We found that both F1 conceived from old fathers and F2 derived from old grandfathers displayed increased ultrasound vocalization (USV) activity, decreased sociability, increased grooming activity and increased anxiety-like responses. Moreover, such abnormalities were partially transmitted to the second generation of mice, having APA grandfathers. In conclusion, our study suggests that the risk of ASD could develop over generations, consistent with heritable mutations and/or epigenetic alterations associated with APA. PMID:24780920

Impact of haze-fog days to radon progeny equilibrium factor and discussion of related factors.

PubMed

Hou, Changsong; Shang, Bing; Zhang, Qingzhao; Cui, Hongxing; Wu, Yunyun; Deng, Jun

2015-11-01

The equilibrium factor F between radon and its short-lived progenies is an important parameter to estimate radon exposure of humans. Therefore, indoor and outdoor concentrations of radon and its short-lived radon progeny were measured in Beijing area using a continuously measuring device, in an effort to obtain information on the F value. The results showed that the mean values of F were 0.58 ± 0.13 (0.25-0.95, n = 305) and 0.52 ± 0.12 (0.31-0.91, n = 64) for indoor and outdoor, respectively. The indoor F value during haze-fog days was higher than the typical value of 0.4 recommended by the United Nations Scientific Committee on the Effects of Atomic Radiation, and it was also higher than the values of 0.47 and 0.49 reported in the literature. A positive correlation was observed between indoor F values and PM2.5 concentrations (R (2) = 0.71). Since 2013, owing to frequent heavy haze-fog events in Beijing and surrounding areas, the number of the days with severe pollution remains at a high level. Future studies on the impact of the ambient fine particulate matter on indoor radon progeny equilibrium factor F could be important.

The Progeny of Arabidopsis thaliana Plants Exposed to Salt Exhibit Changes in DNA Methylation, Histone Modifications and Gene Expression

PubMed Central

Bilichak, Andriy; Ilnystkyy, Yaroslav; Hollunder, Jens; Kovalchuk, Igor

2012-01-01

Plants are able to acclimate to new growth conditions on a relatively short time-scale. Recently, we showed that the progeny of plants exposed to various abiotic stresses exhibited changes in genome stability, methylation patterns and stress tolerance. Here, we performed a more detailed analysis of methylation patterns in the progeny of Arabidopsis thaliana (Arabidopsis) plants exposed to 25 and 75 mM sodium chloride. We found that the majority of gene promoters exhibiting changes in methylation were hypermethylated, and this group was overrepresented by regulators of the chromatin structure. The analysis of DNA methylation at gene bodies showed that hypermethylation in the progeny of stressed plants was primarily due to changes in the 5′ and 3′ ends as well as in exons rather than introns. All but one hypermethylated gene tested had lower gene expression. The analysis of histone modifications in the promoters and coding sequences showed that hypermethylation and lower gene expression correlated with the enrichment of H3K9me2 and depletion of H3K9ac histones. Thus, our work demonstrated a high degree of correlation between changes in DNA methylation, histone modifications and gene expression in the progeny of salt-stressed plants. PMID:22291972

Evidence for the emergence of new rice types of interspecific hybrid origin in West African farmers' fields.

PubMed

Nuijten, Edwin; van Treuren, Robbert; Struik, Paul C; Mokuwa, Alfred; Okry, Florent; Teeken, Béla; Richards, Paul

2009-10-06

In West Africa two rice species (Oryza glaberrima Steud. and Oryza sativa L.) co-exist. Although originally it was thought that interspecific hybridization is impossible without biotechnological methods, progenies of hybridization appear to occur in farmer fields. AFLP analysis was used to assess genetic diversity in West Africa (including the countries The Gambia, Senegal, Guinea Bissau, Guinea Conakry, Sierra Leone, Ghana and Togo) using 315 rice samples morphologically classified prior to analysis. We show evidence for farmer interspecific hybrids of African and Asian rice, resulting in a group of novel genotypes, and identify possible mechanisms for in-field hybridization. Spontaneous back-crossing events play a crucial role, resulting in different groups of genetic diversity in different regions developed by natural and cultural selection, often under adverse conditions. These new groups of genotypes may have potential relevance for exploitation by plant breeders. Future advances in crop development could be achieved through co-operation between scientists and marginalized farmer groups in order to address challenges of rapid adaptation in a world of increasing socio-political and climatic uncertainty.

Evidence for the Emergence of New Rice Types of Interspecific Hybrid Origin in West African Farmers' Fields

PubMed Central

Nuijten, Edwin; van Treuren, Robbert; Struik, Paul C.; Mokuwa, Alfred; Okry, Florent; Teeken, Béla; Richards, Paul

2009-01-01

In West Africa two rice species (Oryza glaberrima Steud. and Oryza sativa L.) co-exist. Although originally it was thought that interspecific hybridization is impossible without biotechnological methods, progenies of hybridization appear to occur in farmer fields. AFLP analysis was used to assess genetic diversity in West Africa (including the countries The Gambia, Senegal, Guinea Bissau, Guinea Conakry, Sierra Leone, Ghana and Togo) using 315 rice samples morphologically classified prior to analysis. We show evidence for farmer interspecific hybrids of African and Asian rice, resulting in a group of novel genotypes, and identify possible mechanisms for in-field hybridization. Spontaneous back-crossing events play a crucial role, resulting in different groups of genetic diversity in different regions developed by natural and cultural selection, often under adverse conditions. These new groups of genotypes may have potential relevance for exploitation by plant breeders. Future advances in crop development could be achieved through co-operation between scientists and marginalized farmer groups in order to address challenges of rapid adaptation in a world of increasing socio-political and climatic uncertainty. PMID:19806197

Investigation of the exposure to radon and progeny in the thermal spas of Loutraki (Attica-Greece): results from measurements and modelling.

PubMed

Nikolopoulos, Dimitrios; Vogiannis, Efstratios; Petraki, Ermioni; Zisos, Athanasios; Louizi, Anna

2010-01-01

Radon and progeny ((218)Po, (214)Pb, (214)Bi and (214)Po) in thermal spas are well known radioactive pollutants identified for additional radiation burden of patients due to the activity concentration peaks which appear during bath treatment or due to drinking of waters of high radon content. This burden affects additionally the working personnel of the spas. The present paper has focused on the thermal spas of Loutraki (Attica-Greece). The aim was the investigation of the health impact for patients and working personnel due to radon and progeny. Attention has been paid to radon and progeny transient concentration peaks (for bath treatment) and to radon of thermal waters (both for bath treatment and drinking therapy). Designed experiments have been carried out, which included radon and progeny activity concentration measurements in thermal waters and ambient air. Additionally, published models for description of radon and progeny transient concentration peaks were employed. The models were based on physicochemical processes involved and employed non linear first order derivative mass balance differential equations which were solved numerically with the aid of specially developed computer codes. The collected measurements were analysed incorporating these models. Results were checked via non linear statistical tests. Predictions and measurements were found in close agreement. Non linear parameters were estimated. The models were employed for dosimetric estimations of patients and working personnel. The effective doses of patients receiving bath treatment were found low but not negligible. The corresponding doses to patients receiving potable treatment were found high but below the proposed international limits. It was found that the working personnel are exposed to considerable effective doses, however well below the acceptable limits for workers. It was concluded that treatment and working in the Loutraki spas leads to intense variations of radon and progeny and

Molecular Genetic Analysis of the Melanoma Regulatory locus in Xiphophorus Interspecies Hybrids

PubMed Central

Lu, Yuan; Boswell, Mikki; Boswell, William; Kneitz, Susanne; Hausmann, Michael; Klotz, Barbara; Regneri, Janine; Savage, Markita; Amores, Angel; Postlethwait, John; Warren, Wesley; Schartl, Manfred; Walter, Ronald

2018-01-01

Development of spontaneous melanoma in Xiphophorus interspecies backcross hybrid progeny, (X. hellerii × [X. maculatus Jp 163 A × X. hellerii]) is due to Mendelian segregation of a oncogene (xmrk) and a molecularly uncharacterized locus, called R(Diff), on LG5. R(Diff) is thought to suppresses the activity of xmrk in healthy X. maculatus Jp 163 A parental species that rarely develop melanoma. To better understand the molecular genetics of R(Diff), we utilized RNA-Seq to study allele-specific gene expression of spontaneous melanoma tumors and corresponding normal skin samples derived from 15 first generation backcross (BC1) hybrids and 13 fifth generation (BC5) hybrids. Allele-specific expression was determined for all genes and assigned to parental allele inheritance for each backcross hybrid individual. Results showed that genes residing in a 5.81 Mbp region on LG5 were exclusively expressed from the X. hellerii alleles in tumor-bearing BC1 hybrids. This observation indicates this region is consistently homozygous for X. hellerii alleles in tumor bearing animals, and therefore defines this region to be the R(Diff) locus. The R(Diff) locus harbors 164 gene models and includes the previously characterized R(Diff) candidate, cdkn2x. Twenty one genes in the R(Diff) region show differential expression in the tumor samples compared to normal skin tissue. These results further characterize the R(Diff) locus and suggest tumor suppression may require a multigenic region rather than a single gene variant. Differences in gene expression between tumor and normal skin tissue in this region may indicate interactions among several genes are required for backcross hybrid melanoma development. PMID:28345808

Genetic determinism of anatomical and hydraulic traits within an apple progeny.

PubMed

Lauri, Pierre-Éric; Gorza, Olivier; Cochard, Hervé; Martinez, Sébastien; Celton, Jean-Marc; Ripetti, Véronique; Lartaud, Marc; Bry, Xavier; Trottier, Catherine; Costes, Evelyne

2011-08-01

The apple tree is known to have an isohydric behaviour, maintaining rather constant leaf water potential in soil with low water status and/or under high evaporative demand. However, little is known on the xylem water transport from roots to leaves from the two perspectives of efficiency and safety, and on its genetic variability. We analysed 16 traits related to hydraulic efficiency and safety, and anatomical traits in apple stems, and the relationships between them. Most variables were found heritable, and we investigated the determinism underlying their genetic control through a quantitative trait loci (QTL) analysis on 90 genotypes from the same progeny. Principal component analysis (PCA) revealed that all traits related to efficiency, whether hydraulic conductivity, vessel number and area or wood area, were included in the first PC, whereas the second PC included the safety variables, thus confirming the absence of trade-off between these two sets of traits. Our results demonstrated that clustered variables were characterized by common genomic regions. Together with previous results on the same progeny, our study substantiated that hydraulic efficiency traits co-localized with traits identified for tree growth and fruit production. © 2011 Blackwell Publishing Ltd.

Life cycle efficiency of beef production: II. Relationship of cow efficiency ratios to traits of the dam and progeny weaned.

PubMed

Davis, M E; Rutledge, J J; Cundiff, L V; Hauser, E R

1983-10-01

Several measures of life cycle cow efficiency were calculated using weights and individual feed consumptions recorded on 160 dams of beef, dairy and beef X dairy breeding and their progeny. Ratios of output to input were used to estimate efficiency, where outputs included weaning weights of progeny plus salvage value of the dam and inputs included creep feed consumed by progeny plus feed consumed by the dam over her entire lifetime. In one approach to estimating efficiency, inputs and outputs were weighted by probabilities that were a function of the cow herd age distribution and percentage calf crop in a theoretical herd. The second approach to estimating cow efficiency involved dividing the sum of the weights by the sum of the feed consumption values, with all pieces of information being given equal weighting. Relationships among efficiency estimates and various traits of dams and progeny were examined. Weights, heights, and weight:height ratios of dams at 240 d of age were not correlated significantly with subsequent efficiency of calf production, indicating that indirect selection for lifetime cow efficiency at an early age based on these traits would be ineffective. However, females exhibiting more efficient weight gains from 240 d to first calving tended to become more efficient dams. Correlations of efficiency with weight of dam at calving and at weaning were negative and generally highly significant. Height at withers was negatively related to efficiency. Ratio of weight to height indicated that fatter dams generally were less efficient. The effect of milk production on efficiency depended upon the breed combinations involved. Dams calving for the first time at an early age and continuing to calve at short intervals were superior in efficiency. Weaning rate was closely related to life cycle efficiency. Large negative correlations between efficiency and feed consumption of dams were observed, while correlations of efficiency with progeny weights and feed

Maternal Exposure to Cadmium and Manganese Impairs Reproduction and Progeny Fitness in the Sea Urchin Paracentrotus lividus

PubMed Central

Migliaccio, Oriana; Castellano, Immacolata; Cirino, Paola; Romano, Giovanna; Palumbo, Anna

2015-01-01

Metal contamination represents one of the major sources of pollution in marine environments. In this study we investigated the short-term effects of ecologically relevant cadmium and manganese concentrations (10-6 and 3.6 x 10-5 M, respectively) on females of the sea urchin Paracentrotus lividus and their progeny, reared in the absence or presence of the metal. Cadmium is a well-known heavy metal, whereas manganese represents a potential emerging contaminant, resulting from an increased production of manganese-containing compounds. The effects of these agents were examined on both P. lividus adults and their offspring following reproductive state, morphology of embryos, nitric oxide (NO) production and differential gene expression. Here, we demonstrated that both metals differentially impaired the fertilization processes of the treated female sea urchins, causing modifications in the reproductive state and also affecting NO production in the ovaries. A detailed analysis of the progeny showed a high percentage of abnormal embryos, associated to an increase in the endogenous NO levels and variations in the transcriptional expression of several genes involved in stress response, skeletogenesis, detoxification, multi drug efflux processes and NO production. Moreover, we found significant differences in the progeny from females exposed to metals and reared in metal-containing sea water compared to embryos reared in non-contaminated sea water. Overall, these results greatly expanded previous studies on the toxic effects of metals on P. lividus and provided new insights into the molecular events induced in the progeny of sea urchins exposed to metals. PMID:26125595

Early flowering and seed production in a yellow birch progeny test

Treesearch

Knud E. Clausen

1976-01-01

Trees in a yellow birch progeny test began to bear seed when 7 years old and the proportion of fruiting trees increased in the following 2 years. Male catkins were produced at age 8 and the number of trees with males increased greatly the following years. Although there is much variation between and within families in earliness of flowering and in number of flowers and...

Analysis of disconnected diallel mating designs II: results from a third generation progeny test of the New Zealand radiata pine improvement programme.

Treesearch

J.N. King; M.J. Carson; G.R. Johnson

1998-01-01

Genetic parameters from a second generation (F2) disconnected diallel progeny test of the New Zealand radiata pine improvement programme are presented. Heritability estimates of growth and yield traits of 0.2 are similar to progeny test results of the previous generation (F1) generation tests. A trend of declining dominance...

Progeny Density and Nest Availability Affect Parasitism Risk and Reproduction in a Solitary Bee (Osmia lignaria) (Hymenoptera: Megachilidae).

PubMed

Farzan, Shahla

2018-02-08

Gregarious nesting behavior occurs in a broad diversity of solitary bees and wasps. Despite the prevalence of aggregative nesting, the underlying drivers and fitness consequences of this behavior remain unclear. I investigated the effect of two key characteristics of nesting aggregations (cavity availability and progeny density) on reproduction and brood parasitism rates in the blue orchard bee (Osmia lignaria Say) (Hymenoptera: Megachilidae), a solitary species that nests gregariously and appears to be attracted to nesting conspecifics. To do so, I experimentally manipulated nest cavity availability in a region of northern Utah with naturally occurring populations of O. lignaria. Nest cavity availability had a negative effect on cuckoo bee (Stelis montana Cresson) (Hymenoptera: Megachilidae) parasitism rates, with lower parasitism rates occurring in nest blocks with more available cavities. For both S. montana and the cleptoparasitic blister beetle Tricrania stansburyi Haldeman (Coleoptera: Meloidae), brood parasitism rate was negatively correlated with log-transformed O. lignaria progeny density. Finally, cavity availability had a positive effect on male O. lignaria body weight, with the heaviest male progeny produced in nest blocks with the most cavities. These results suggest that cavity availability and progeny density can have substantial effects on brood parasitism risk and reproduction in this solitary bee species. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Mapping of the bcl-2 oncogene on mouse chromosome 1.

PubMed

Mock, B A; Givol, D; D'Hoostelaere, L A; Huppi, K; Seldin, M F; Gurfinkel, N; Unger, T; Potter, M; Mushinski, J F

1988-01-01

Two bcl-2 alleles have been identified in inbred strains of mice by restriction fragment length polymorphism (RFLP). Analysis of a bcl-2 RFLP in a series of bilineal congenic strains (C.D2), developed as a tool for chromosomal mapping studies, revealed linkage of bcl-2 to the Idh-1/Pep-3 region of murine chromosome 1. The co-segregation of bcl-2 alleles with allelic forms of two other chromosome 1 loci, Ren-1,2 and Spna-1, in a set of back-cross progeny, positions bcl-2 7.8 cM centromeric from Ren-1,2.

Genomic introgression mapping of field-derived multiple-anthelmintic resistance in Teladorsagia circumcincta

PubMed Central

Hallsworth-Pepin, Kymberlie; Martin, John; Mitreva, Makedonka

2017-01-01

Preventive chemotherapy has long been practiced against nematode parasites of livestock, leading to widespread drug resistance, and is increasingly being adopted for eradication of human parasitic nematodes even though it is similarly likely to lead to drug resistance. Given that the genetic architecture of resistance is poorly understood for any nematode, we have analyzed multidrug resistant Teladorsagia circumcincta, a major parasite of sheep, as a model for analysis of resistance selection. We introgressed a field-derived multiresistant genotype into a partially inbred susceptible genetic background (through repeated backcrossing and drug selection) and performed genome-wide scans in the backcross progeny and drug-selected F2 populations to identify the major genes responsible for the multidrug resistance. We identified variation linking candidate resistance genes to each drug class. Putative mechanisms included target site polymorphism, changes in likely regulatory regions and copy number variation in efflux transporters. This work elucidates the genetic architecture of multiple anthelmintic resistance in a parasitic nematode for the first time and establishes a framework for future studies of anthelmintic resistance in nematode parasites of humans. PMID:28644839

Isolation and genetic mapping of a Coffea canephora phenylalanine ammonia-lyase gene (CcPAL1) and its involvement in the accumulation of caffeoyl quinic acids.

PubMed

Mahesh, Venkataramaiah; Rakotomalala, Jean Jacques; Le Gal, Lénaïg; Vigne, Hélène; de Kochko, Alexandre; Hamon, Serge; Noirot, Michel; Campa, Claudine

2006-09-01

Biosynthesis of caffeoylquinic acids occurs via the phenylpropanoid pathway in which the phenylalanine ammonia-lyase (PAL) acts as a key-control enzyme. A full-length cDNA (pF6), corresponding to a PAL gene (CcPAL1), was isolated by screening a Coffea canephora fruit cDNA library and its corresponding genomic sequence was characterized. Amplification of total DNA from seven Coffea species revealed differences in intronic length. This interspecific polymorphism was used to locate the gene on a genetic map established for a backcross progeny between Coffea pseudozanguebariae and C. dewevrei. The CcPAL1 gene was found on the same linkage group, but genetically independent, as a caffeoyl-coenzyme A-O-methyltransferase gene, another gene intervening in the phenylpropanoid pathway. In the same backcross, a lower caffeoylquinic acid content was observed in seeds harvested from plants harbouring the C. pseudozanguebariae CcPAL1 allele. Involvement of the CcPAL1 allelic form in the differential accumulation of caffeoylquinic acids in coffee green beans is then discussed.

Genetic effect of the Aegilops caudata plasmon on the manifestation of the Ae. cylindrica genome.

PubMed

Tsunewaki, Koichiro; Mori, Naoki; Takumi, Shigeo

2014-01-01

In the course of reconstructing Aegilops caudata from its own genome (CC) and its plasmon, which had passed half a century in common wheat (genome AABBDD), we produced alloplasmic Ae. cylindrica (genome CCDD) with the plasmon of Ae. caudata. This line, designated (caudata)-CCDD, was found to express male sterility in its second substitution backcross generation (SB2) of (caudata)-AABBCCDD pollinated three times with the Ae. cylindrica pollen. We repeatedly backcrossed these SB2 plants with the Ae. cylindrica pollen until the SB5 generation, and SB5F2 progeny were produced by self-pollination of the SB5 plants. Thirteen morphological and physiological characters, including pollen and seed fertilities, of the (caudata)-CCDD SB5F2 were compared with those of the euplasmic Ae. cylindrica. The results indicated that the male sterility expressed by (caudata)-CCDD was due to genetic incompatibility between the Ae. cylindrica genome and Ae. caudata plasmon that did not affect any other characters of Ae. cylindrica. Also, we report that the genome integrity functions in keeping the univalent transmission rate high.

Inherent Variation Among Slash Pine Progenies at the Ida Cason Callaway Foundation

Treesearch

John C. Barber

1964-01-01

Reported here in detail is information obtained from two open-pollinated progeny tests of slash pine at the Ida Cason Callaway Foundation, Pine Mountain, Georgia. Because of the small amount of similar data available to tree improvement workers, it was decided to include as much information as possible, even though some of it is too limited for statistical analyses...

Evaluation of human embryonic stem cells and their differentiated fibroblastic progenies as cellular models for in vitro genotoxicity screening.

PubMed

Vinoth, Kumar Jayaseelan; Manikandan, Jayapal; Sethu, Swaminathan; Balakrishnan, Lakshmidevi; Heng, Alexis; Lu, Kai; Hande, Manoor Prakash; Cao, Tong

2014-08-20

This study evaluated human embryonic stem cells (hESC) and their differentiated fibroblastic progenies as cellular models for genotoxicity screening. The DNA damage response of hESCs and their differentiated fibroblastic progenies were compared to a fibroblastic cell line (HEPM, CRL1486) and primary cultures of peripheral blood lymphocytes (PBL), upon exposure to Mitomycin C, gamma irradiation and H2O2. It was demonstrated that hESC-derived fibroblastic progenies (H1F) displayed significantly higher chromosomal aberrations, micronuclei formation and double strand break (DSB) formation, as compared to undifferentiated hESC upon exposure to genotoxic stress. Nevertheless, H1F cell types displayed comparable sensitivities to genotoxic challenge as HEPM and PBL, both of which are representative of somatic cell types commonly used for genotoxicity screening. Subsequently, transcriptomic and pathways analysis identified differential expression of critical genes involved in cell death and DNA damage response upon exposure to gamma irradiation. The results thus demonstrate that hESC-derived fibroblastic progenies are as sensitive as commonly-used somatic cell types for genotoxicity screening. Moreover, hESCs have additional advantages, such as their genetic normality compared to immortalized cell lines, as well as their amenability to scale-up for producing large, standardized quantities of cells for genotoxicity screening on an industrial scale, something which can never be achieved with primary cell cultures. Copyright © 2014. Published by Elsevier B.V.

AGE-DEPENDENT INHALATION DOSE DUE TO EXPOSURE OF SHORT LIVED PROGENY OF RADON AND THORON FOR DIFFERENT AGE GROUPS IN JAMMU & KASHMIR, HIMALAYAS.

PubMed

Sharma, Sumit; Kumar, Ajay; Mehra, Rohit

2018-05-16

Dosimetric approach is used in this study for the assessment of doses due to inhalation of short lived radon/thoron progeny to the inhabitants of Udhampur district of Jammu & Kashmir. This paper also presents the activity concentrations and unattached fraction of radon and thoron progeny. The observed annual concentration of attached and unattached 222Rn and 220Rn progeny has been found to vary from 8 to 32 and 0.09 to 14 Bq/m3, 0.75 to 3.16 and 0.01 to 1.13 Bq/m3, respectively. The inhalation doses from radon progeny to different body organs of different age groups have been calculated by using the age dependent biokinetic model. The attachment rate of 222Rn and indoor aerosol concentration of 222Rn and 220Rn have been estimated and their relation between them has also been studied. The dose conversion factor for mouth and nasal breathing to different exposure conditions has been obtained from Porstendorfer model.

Effect of late gestation bodyweight change and condition score on progeny feedlot performance

USDA-ARS?s Scientific Manuscript database

Inadequate nutrient intake during late gestation can cause cow BW loss and influence cow reproductive performance and subsequent productivity of steer progeny. Therefore, a 7-yr study with a 3 × 3 arrangement of treatments was conducted at Corona Range and Livestock Research Center, Corona, NM to e...

Maternal inheritance of the chloroplast genome in Eucalyptus globulus and interspecific hybrids.

PubMed

Mckinnon, A E; Vaillancourt, R E; Tilyard, P A; Potts, B M

2001-10-01

The utility of chloroplast DNA (cpDNA) in Eucalyptus, either as a molecular marker for genetic studies or as a potential vehicle for genetic manipulation, is based on knowledge of its mode of inheritance. Chloroplast inheritance in angiosperms can vary among and within species, and anomalous inheritance has been reported in some interspecific-hybrid combinations. In Eucalyptus, abnormalities of pollen-tube growth occur in a number of interspecific-hybrid combinations, and this might increase the likelihood of anomalous chloroplast transmission. We used a rapid PCR technique to determine chloroplast heritability in 425 progeny of Eucalyptus, comprising 194 progeny of the premier pulpwood species E. globulus and 231 interspecific hybrids between E. globulus and E. nitens (F1, F2, and backcrosses). At this sampling intensity, no pollen-mediated transmission of cpDNA was found in any of the 40 families tested. The results are discussed with reference to chloroplast engineering and the use of cpDNA as a seed-specific marker in phylogeographic studies of Eucalyptus.

Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny in the human lung.

PubMed

Nikezic, D; Lau, B M F; Stevanovic, N; Yu, K N

2006-01-01

To calculate the absorbed dose in the human lung due to inhaled radon progeny, ICRP focussed on the layers containing the target cells, i.e., the basal and secretory cells. Such an approach did not consider details of the sensitive cells in the layers. The present work uses the microdosimetric approach and determines the absorbed alpha-particle energy in non-spherical nuclei of target cells (basal and secretory cells). The absorbed energy for alpha particles emitted by radon progeny in the human respiratory tract was calculated in basal- and secretory-cell nuclei, assuming conical and ellipsoidal forms for these cells. Distributions of specific energy for different combinations of alpha-particle sources, energies and targets are calculated and shown. The dose conversion coefficient for radon progeny is reduced for about 2mSv/WLM when conical and ellipsoidal cell nuclei are considered instead of the layers. While changes in the geometry of secretory-cell nuclei do not have significant effects on their absorbed dose, changes from spherical to conical basal-cell nuclei have significantly reduced their absorbed dose from approximately 4 to approximately 3mGy/WLM. This is expected because basal cells are situated close to the end of the range of 6MeV alpha particles. This also underlines the significance of better and more precise information on targets in the T-B tree. A further change in the dose conversion coefficient can be achieved if a different weighting scheme is adopted for the doses for the cells. The results demonstrate the necessity for better information on the target cells for more accurate dosimetry for radon progeny.

Ethanol Consumption by Wistar Rat Dams Affects Selenium Bioavailability and Antioxidant Balance in Their Progeny

PubMed Central

Ojeda, María Luisa; Vázquez, Beatriz; Nogales, Fátima; Murillo, María Luisa; Carreras, Olimpia

2009-01-01

Ethanol consumption affects maternal nutrition, the mothers’ antioxidant balance and the future health of their progeny. Selenium (Se) is a trace element cofactor of the enzyme glutathione peroxidase (GPx). We will study the effect of ethanol on Se bioavailability in dams and in their progeny. We have used three experimental groups of dams: control, chronic ethanol and pair-fed; and three groups of pups. Se levels were measured by graphite-furnace atomic absorption spectrometry. Serum and hepatic GPx activity was determined by spectrometry. We have concluded that ethanol decreased Se retention in dams, affecting their tissue Se deposits and those of their offspring, while also compromising their progeny’s weight and oxidation balance. These effects of ethanol are caused by a reduction in Se intake and a direct alcohol-generated oxidation action. PMID:19742151

Indoor concentration of radon, thoron and their progeny around granite regions in the state of Karnataka, India.

PubMed

Sannappa, J; Ningappa, C

2014-03-01

An extensive studies on the indoor activity concentrations of thoron, radon and their progeny in the granite region in the state of Karnataka, India, has been carried out since, 2007 in the scope of a lung cancer epidemiological study using solid-state nuclear track detector-based double-chamber dosemeters (LR-115, type II plastic track detector). Seventy-four dwellings of different types were selected for the measurement. The dosemeters containing SSNTD detectors were fixed 2 m above the floor. After an exposure time of 3 months (90 d), films were etched to reveal tracks. From the track density, the concentrations of radon and thoron were evaluated. The value of the indoor concentration of thoron and radon in the study area varies from 16 to 170 Bq m(-3) and 18 to 300 Bq m(-3) with medians of 66 and 82.3 Bq m(-3), respectively, and that of their progeny varies from 1.8 to 24 mWL with a median of 3.6 mWL and 1.6 to 19.6 mWL, respectively. The concentrations of indoor thoron, radon and their progeny and their equivalent effective doses are discussed.

Morphometric and functional abnormalities of kidneys in the progeny of mice fed chocolate during pregnancy and lactation.

PubMed

Patera, Janusz; Chorostowska-Wynimko, Joanna; Słodkowska, Janina; Borowska, Adamina; Skopiński, Piotr; Sommer, Ewa; Wasiutyński, Aleksander; Skopińska-Rózewska, Ewa

2006-01-01

Even most commonly consumed beverages like tea, coffee, chocolate and cocoa contain methylxanthines, biogenic amines and polyphenols, among them catechins, that exhibit significant biological activity and might profoundly affect the organism homeostasis. We have previously shown that 400 mg of bitter chocolate or 6 mg of theobromine added to the daily diet of pregnant and afterwards lactating mice affected embryonic angiogenesis and caused bone mineralization disturbances as well as limb shortening in 4-weeks old offspring. The aim of the present study was the morphometric and functional evaluation of kidneys in the 4-weeks old progeny mice fed according to the protocol mentioned above. Progeny from the mice fed chocolate presented considerable morphometric abnormalities in the kidney structure, with the lower number of glomeruli per mm2 and their increased diameter. Moreover, higher serum creatinine concentration was observed in that group of offspring. No morphometric or functional irregularities were found in the progeny of mice fed theobromine. Abnormalities demonstrated in the offspring of mice fed chocolate are not related to its theobromine content. Consequently, identification of active compound(s) responsible for the observed effects is of vital importance.

Mapping quantitative trait loci controlling milk production in dairy cattle by exploiting progeny testing

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

Georges, M.; Nielsen, D.; Mackinnon, M.

1995-02-01

We have exploited {open_quotes}progeny testing{close_quotes} to map quantitative trait loci (QTL) underlying the genetic variation of milk production in a selected dairy cattle population. A total of 1,518 sires, with progeny tests based on the milking performances of >150,000 daughters jointly, was genotyped for 159 autosomal microsatellites bracketing 1645 centimorgan or approximately two thirds of the bovine genome. Using a maximum likelihood multilocus linkage analysis accounting for variance heterogeneity of the phenotypes, we identified five chromosomes giving very strong evidence (LOD score {ge} 3) for the presence of a QTL controlling milk production: chromosomes 1, 6, 9, 10 and 20.more » These findings demonstrate that loci with considerable effects on milk production are still segregating in highly selected populations and pave the way toward marker-assisted selection in dairy cattle breeding. 44 refs., 4 figs., 3 tabs.« less

Assessing the Potential Oleoresin Yields of Slash Pine Progenies at Juvenile Ages

Treesearch

A.E. Squillace; Charles R. Gansel

1968-01-01

The potential oleoresin yields of slash pine progenies can be assessed at juvenile ages, 7 to 8 years earlier than with previous methods. Seeds are sown in peat pots, outplanted shortly after germination at a spacing of 14 by 3 feet, and given intensive cultural treatment. At 26 years from seed, when the trees average about 9 feet tall, their potential yields are...

Azadirachtin effects on mating success, gametic abnormalities and progeny survival in Drosophila melanogaster (Diptera).

PubMed

Oulhaci, Chemseddine M; Denis, Béatrice; Kilani-Morakchi, Samira; Sandoz, Jean-Christophe; Kaiser, Laure; Joly, Dominique; Aribi, Nadia

2018-01-01

Azadirachtin is a prominent natural pesticide and represents an alternative to conventional insecticides. It has been successfully used against insect pests. However, its effects on reproduction require further analysis. Here we investigated lethal and sublethal effects of azadirachtin, on treated adults in a model insect, Drosophila melanogaster (Meigen). Dose-mortality relationships as well as several parameters of reproduction (mating, spermatogenesis, oogenesis and fertility) were examined. Neem-Azal, a commercial formulation of azadirachtin, applied topically on newly emerged adults, increased mortality with a positive dose-dependent relationship. The LD 50 (0.63 μg) was determined 24 h after treatment using a non-linear regression. Adults surviving this dose had a mating success that was divided by 3 and a progeny production reduced by half when males were treated, and even more when females were treated. When combining probability of survival, of mating and reduced progeny, it appeared that LD 50 induced a 98% reduction in reproductive rates. Reduced progeny was partially explained by the effect of adult treatment on gametes number and abnormalities. The number of cysts and the apical nuclei positions within the cysts decreased by 29.7% and 20%, respectively, in males. In females, the number of oocytes per ovary and the volume of basal oocytes also decreased by 16.1% and 32.4%, respectively. Azadirachtin causes significant toxic effects in both sexes and decreases the fecundity and fertility of D. melanogaster. Females are more sensitive to azadirachtin. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

The predatory mite Phytoseiulus persimilis adjusts patch-leaving to own and progeny prey needs.

PubMed

Vanas, V; Enigl, M; Walzer, A; Schausberger, P

2006-01-01

Integration of optimal foraging and optimal oviposition theories suggests that predator females should adjust patch leaving to own and progeny prey needs to maximize current and future reproductive success. We tested this hypothesis in the predatory mite Phytoseiulus persimilis and its patchily distributed prey, the two-spotted spider mite Tetranychus urticae. In three separate experiments we assessed (1) the minimum number of prey needed to complete juvenile development, (2) the minimum number of prey needed to produce an egg, and (3) the ratio between eggs laid and spider mites left when a gravid P. persimilis female leaves a patch. Experiments (1) and (2) were the pre-requirements to assess the fitness costs associated with staying or leaving a prey patch. Immature P. persimilis needed at least 7 and on average 14+/-3.6 (SD) T. urticae eggs to reach adulthood. Gravid females needed at least 5 and on average 8.5+/-3.1 (SD) T. urticae eggs to produce an egg. Most females left the initial patch before spider mite extinction, leaving prey for progeny to develop to adulthood. Females placed in a low density patch left 5.6+/-6.1 (SD) eggs per egg laid, whereas those placed in a high density patch left 15.8+/-13.7 (SD) eggs per egg laid. The three experiments in concert suggest that gravid P. persimilis females are able to balance the trade off between optimal foraging and optimal oviposition and adjust patch-leaving to own and progeny prey needs.

Oleoresin characteristics of progeny of loblolly pines that escaped attack by southern pine beetle

Treesearch

B.L. Strom; R.A. Goyer; L.L. Ingram; G.D.L. Boyd; L.H. Lott

2002-01-01

Oleoresin characteristics of first-generation (F1) progeny of loblolly pines (Pinus taeda L.) that escaped mortality from the southern pine beetle, Dendroctonus frontalis Zimmermann (Coleoptera: Scolytidae), despite heavy mortality of neighbors, were evaluated and compared to trees from a general (i.e., trees...

Transient gestational exposure to drinking water containing excess hexavalent chromium modifies insulin signaling in liver and skeletal muscle of rat progeny.

PubMed

Shobana, Navaneethabalakrishnan; Aruldhas, Mariajoseph Michael; Tochhawng, Lalmuankimi; Loganathan, Ayyalu; Balaji, Sadhasivam; Kumar, Mani Kathiresh; Banu, Liaquat Alikhan Sheerin; Navin, Ajit Kumar; Mayilvanan, Chinnaiyan; Ilangovan, Ramachandran; Balasubramanian, Karundevi

2017-11-01

Chromium (Cr), an essential micronutrient potentiates insulin action, whereas excess hexavalent Cr (CrVI) acts as an endocrine disruptor. Pregnant mothers living in areas abutting industries using the metal and chromite ore dumps are exposed to ground water contaminated with Cr. Nevertheless, the impact of prenatal exposure to excess CrVI on insulin signaling in the progeny remains obscure. We tested the hypothesis "transient gestational exposure to drinking water containing excess CrVI may modify insulin signaling during postnatal life". Pregnant Wistar rats were given drinking water containing 50, 100 and 200 ppm CrVI (K 2 Cr 2 O 7 ) from gestational day 9-14 encompassing the period of organogenesis; the male progenies were tested at postnatal day 60. Neither fasting blood glucose nor oral glucose tolerance was altered in CrVI treated progeny. Nevertheless, western blot detection pointed out attenuated expression level of insulin receptor (IR), its downstream signaling molecules (IRS-1, pIRS-1 Tyr632 , Akt and pAkt Ser473 ) and organ specific glucose transporters (GLUT2 in liver and GLUT4 in gastrocnemius muscle), along with a significant increase in serum insulin level in male progenies exposed to CrVI. While 14 C-2-deoxy glucose uptake increased in the liver, the same decreased in the skeletal muscle whereas, 14 C-glucose oxidation recorded a consistent decrease in both tissues of CrVI exposed rats. These findings support our hypothesis and suggest that transient gestational exposure to excess CrVI may affect insulin signaling and glucose oxidation in the progeny, predictably rendering them vulnerable to insulin resistance. Copyright © 2017 Elsevier B.V. All rights reserved.

Beneficial effect of feeding a ketogenic diet to mothers on brain development in their progeny with a murine model of pyruvate dehydrogenase complex deficiency.

PubMed

Pliss, Lioudmila; Jatania, Urvi; Patel, Mulchand S

2016-06-01

Pyruvate dehydrogenase complex (PDC) deficiency is a major inborn error of oxidative metabolism of pyruvate in the mitochondria causing congenital lactic acidosis and primarily structural and functional abnormalities of the central nervous system. To provide an alternate source of acetyl-CoA derived from ketone bodies to the developing brain, a formula high in fat content is widely employed as a treatment. In the present study we investigated efficacy of a high-fat diet given to mothers during pregnancy and lactation on lessening of the impact of PDC deficiency on brain development in PDC-deficient female progeny. A murine model of systemic PDC deficiency by interrupting the X-linked Pdha1 gene was employed in this study. Maternal consumption of a high-fat diet during pregnancy and lactation had no effect on number of live-birth, body growth, tissue PDC activity levels, as well as the in vitro rates of glucose oxidation and fatty acid biosynthesis by the developing brain of PDC-deficient female offspring during the postnatal age 35 days, as compared to the PDC-deficient progeny born to dams on a chow diet. Interestingly, brain weight was normalized in PDC-deficient progeny of high fat-fed mothers with improvement in impairment in brain structure deficit whereas brain weight was significantly decreased and was associated with greater cerebral structural defects in progeny of chow-fed mothers as compared to control progeny of mothers fed either a chow or high fat diet. The findings provide for the first time experimental support for beneficial effects of a ketogenic diet during the prenatal and early postnatal periods on the brain development of PDC-deficient mammalian progeny.

A Combined Classical Genetic and High Resolution Two-Dimensional Electrophoretic Approach to the Assessment of the Number of Genes Affecting Hybrid Male Sterility in Drosophila Simulans and Drosophila Sechellia

PubMed Central

Zeng, L. W.; Singh, R. S.

1993-01-01

We have attempted to estimate the number of genes involved in postzygotic reproductive isolation between two closely related species, Drosophila simulans and Drosophila sechellia, by a novel approach that involves the use of high resolution two-dimensional gel electrophoresis (2DE) to examine testis proteins in parents, hybrids and fertile and sterile backcross progenies. The important results that have emerged from this study are as follows: (1) about 8% of about 1000 proteins examined showed divergence (presence/absence) between the two species; (2) by tracing individual proteins in parental, hybrid and backcross males, we were able to associate the divergent proteins with different chromosomes and found that most divergent proteins are associated with autosomes and very few with X chromosome, Y chromosome and cytoplasm; (3) when proteins showing both quantitative and qualitative differences between the two species were examined in F(1) hybrid males, most (97.4%) proteins were expressed at levels between the two parents and no sign of large scale changes in spot density was observed. All the proteins observed in the two parental species were present in F(1) hybrid males except two species-specific proteins that may be encoded (or regulated) by sex chromosomes; (4) when different fertile and sterile backcross male testes were compared, a few D. sechellia-specific proteins were identified to be consistently associated with male sterility. These results along with the observation that a large proportion (23.6%) of first generation backcross males were fertile show that hybrid male sterility between D. simulans and D. sechellia involves a relatively small number of genes. Role of large scale genetic changes due to general genome incompatibility is not supported. The results also suggest that the large effect of X chromosome on hybrid male sterility is not due to higher divergence of X chromosome than autosomes. PMID:8224814

A combined classical genetic and high resolution two-dimensional electrophoretic approach to the assessment of the number of genes affecting hybrid male sterility in Drosophila simulans and Drosophila sechellia.

PubMed

Zeng, L W; Singh, R S

1993-09-01

We have attempted to estimate the number of genes involved in postzygotic reproductive isolation between two closely related species, Drosophila simulans and Drosophila sechellia, by a novel approach that involves the use of high resolution two-dimensional gel electrophoresis (2DE) to examine testis proteins in parents, hybrids and fertile and sterile backcross progenies. The important results that have emerged from this study are as follows: (1) about 8% of about 1000 proteins examined showed divergence (presence/absence) between the two species; (2) by tracing individual proteins in parental, hybrid and backcross males, we were able to associate the divergent proteins with different chromosomes and found that most divergent proteins are associated with autosomes and very few with X chromosome, Y chromosome and cytoplasm; (3) when proteins showing both quantitative and qualitative differences between the two species were examined in F1 hybrid males, most (97.4%) proteins were expressed at levels between the two parents and no sign of large scale changes in spot density was observed. All the proteins observed in the two parental species were present in F1 hybrid males except two species-specific proteins that may be encoded (or regulated) by sex chromosomes; (4) when different fertile and sterile backcross male testes were compared, a few D. sechellia-specific proteins were identified to be consistently associated with male sterility. These results along with the observation that a large proportion (23.6%) of first generation backcross males were fertile show that hybrid male sterility between D. simulans and D. sechellia involves a relatively small number of genes. Role of large scale genetic changes due to general genome incompatibility is not supported. The results also suggest that the large effect of X chromosome on hybrid male sterility is not due to higher divergence of X chromosome than autosomes.

Detection of 210Po on filter papers 16 years after use for the collection of short-lived radon progeny in a room.

PubMed

Abu-Jarad, F; Fazal-ur-Rehman

2003-01-01

Radon gas was allowed to accumulate in its radium source and then injected into a 36 m(3) test room, resulting in an initial radon concentration of 15 kBq m(-3). Filter papers were used to collect the short-lived radon progeny and thus to measure the Potential Alpha Energy Concentration (PAEC) in-situ in the year 1984 at different times and conditions according to the experimental design. The radon progeny collected on the filter papers were studied as a function of aerosol particle concentration ranging from 10(2)-10(5) particles cm(-3) in three different experiments. The highest aerosol particle concentration was generated by indoor cigarette smoking. Those filters were stored after the experiment, and were used after 16 years to study the activity of the radon long-lived alpha emitter progeny, (210)Po (T(1/2)=138 days). This isotope is separated from the short-lived progeny by (210)Pb beta emitter with 22.3 years half-life. After 16 years' storage of these filters, each filter paper was sandwiched and wrapped between two CR-39 nuclear track detectors, to put the detectors in contact with the surfaces of different filters, for 337 days. Correlation between the PAEC measured using filter papers in the year 1984 and the activity of long-lived alpha emitter (210)Po on the same filter papers measured in the year 2000 were studied. The results of the (210)Po activity showed a very good correlation of 0.92 with the PAEC 16 years ago. The results also depict that the PAEC and (210)Po activity in indoor air increased with the increase of aerosol particle concentration, which shows the attachment of short-lived radon progeny with the aerosol particles. The experiment proves that indoor cigarette smoking is a major source of aerosol particles carrying radon progeny and, thus, indoor cigarette smoking is an additional source of internal radiation hazard to the occupants whether smoker or non-smoker.

Live animal measurements, carcass composition and plasma hormone and metabolite concentrations in male progeny of sires differing in genetic merit for beef production.

PubMed

Clarke, A M; Drennan, M J; McGee, M; Kenny, D A; Evans, R D; Berry, D P

2009-07-01

In genetic improvement programmes for beef cattle, the effect of selecting for a given trait or index on other economically important traits, or their predictors, must be quantified to ensure no deleterious consequential effects go unnoticed. The objective was to compare live animal measurements, carcass composition and plasma hormone and metabolite concentrations of male progeny of sires selected on an economic index in Ireland. This beef carcass index (BCI) is expressed in euros and based on weaning weight, feed intake, carcass weight and carcass conformation and fat scores. The index is used to aid in the genetic comparison of animals for the expected profitability of their progeny at slaughter. A total of 107 progeny from beef sires of high (n = 11) or low (n = 11) genetic merit for the BCI were compared in either a bull (slaughtered at 16 months of age) or steer (slaughtered at 24 months of age) production system, following purchase after weaning (8 months of age) from commercial beef herds. Data were analysed as a 2 × 2 factorial design (two levels of genetic merit by two production systems). Progeny of high BCI sires had heavier carcasses, greater (P < 0.01) muscularity scores after weaning, greater (P < 0.05) skeletal scores and scanned muscle depth pre-slaughter, higher (P < 0.05) plasma insulin concentrations and greater (P < 0.01) animal value (obtained by multiplying carcass weight by carcass value, which was based on the weight of meat in each cut by its commercial value) than progeny of low BCI sires. Regression of progeny performance on sire genetic merit was also undertaken across the entire data set. In steers, the effect of BCI on carcass meat proportion, calculated carcass value (c/kg) and animal value was positive (P < 0.01), while a negative association was observed for scanned fat depth pre-slaughter and carcass fat proportion (P < 0.01), but there was no effect in bulls. The effect of sire expected progeny difference (EPD) for carcass weight

Maternal antibody transfer to broiler progeny varies among strains and is affected by grain source and cage density.

PubMed

Leandro, N M; Ali, R; Koci, M; Moraes, V; Eusebio-Balcazar, P E; Jornigan, J; Malheiros, R D; Wineland, M J; Brake, J; Oviedo-Rondón, E O

2011-12-01

Two experiments were conducted to examine the effects of broiler breeder dietary grain source and cage density on maternal antibody (MatAb) transfer to progeny in 2 genetic strains (A and B). Broiler breeders were assigned to 16 litter floor pens and fed either corn- or wheat-based diets. Breeders were administered 4 live vaccines against Newcastle disease virus (NDV). At 23 wk of age, pullets and cocks, which reflected the full BW distribution from each treatment, were moved to a cage breeder house and placed at 1 or 2 hens/cage. Breeders were artificially inseminated at 44 wk (experiment 1) and 52 wk of age (experiment 2). Eggs were collected for 8 d, incubated, and placed in individual pedigree bags at d 19 of incubation. Blood samples from 5 chicks per treatment combination were collected at hatch in both experiments. Spleen and bursa were collected from the same chicks for histomorphometry analyses in experiment 2. In the second experiment, 12 chicks per treatment were placed in cages. Progeny were provided diets based on the same grain (corn or wheat) as their parents. Serum samples were collected at 5, 9, and 13 d of age and analyzed for anti-NDV MatAb. Data were analyzed as a 2 × 2 × 2 factorial design considering strain, dietary grain source, and cage density as main factors. Interaction effects were observed in breeders and progeny. Experiment 1 showed that strain A chicks had lower levels of MatAb when hens were housed at 2 hens/cage rather than 1 hen/cage. The MatAb levels of strain B chickens were not affected by cage density in either experiment. Experiment 2 demonstrated similar effects of cage density on MatAb levels and the area of bursa follicles for both strains. Progeny of breeders fed corn-based diets had smaller spleen white pulp only when hens were housed at 2 hens/cage compared with 1 hen/cage. The results of these experiments suggest that breeder strain and cage-density conditions affected MatAb transfer to progeny and embryo development

A method of discriminating transuranic radionuclides from radon progeny using low-resolution alpha spectroscopy and curve-fitting techniques.

PubMed

Konzen, Kevin; Brey, Richard

2012-05-01

²²²Rn (radon) and ²²⁰Rn (thoron) progeny are known to interfere with determining the presence of long-lived transuranic radionuclides, such as plutonium and americium, and require from several hours up to several days for conclusive results. Methods are proposed that should expedite the analysis of air samples for determining the amount of transuranic radionuclides present using low-resolution alpha spectroscopy systems available from typical alpha continuous air monitors (CAMs) with multi-channel analyzer (MCA) capabilities. An alpha spectra simulation program was developed in Microsoft Excel visual basic that employed the use of Monte Carlo numerical methods and serial-decay differential equations that resembled actual spectra. Transuranic radionuclides were able to be quantified with statistical certainty by applying peak fitting equations using the method of least squares. Initial favorable results were achieved when samples containing radon progeny were decayed 15 to 30 min, and samples containing both radon and thoron progeny were decayed at least 60 min. The effort indicates that timely decisions can be made when determining transuranic activity using available alpha CAMs with alpha spectroscopy capabilities for counting retrospective air samples if accompanied by analyses that consider the characteristics of serial decay.

Increased frequency of spontaneous neoplastic transformation in progeny of bystander cells from cultures exposed to densely ionizing radiation.

PubMed

Buonanno, Manuela; de Toledo, Sonia M; Azzam, Edouard I

2011-01-01

An increased risk of carcinogenesis caused by exposure to space radiation during prolonged space travel is a limiting factor for human space exploration. Typically, astronauts are exposed to low fluences of ionizing particles that target only a few cells in a tissue at any one time. The propagation of stressful effects from irradiated to neighboring bystander cells and their transmission to progeny cells would be of importance in estimates of the health risks of exposure to space radiation. With relevance to the risk of carcinogenesis, we investigated, in model C3H 10T½ mouse embryo fibroblasts (MEFs), modulation of the spontaneous frequency of neoplastic transformation in the progeny of bystander MEFs that had been in co-culture 10 population doublings earlier with MEFs exposed to moderate doses of densely ionizing iron ions (1 GeV/nucleon) or sparsely ionizing protons (1 GeV). An increase (P<0.05) in neoplastic transformation frequency, likely mediated by intercellular communication through gap junctions, was observed in the progeny of bystander cells that had been in co-culture with cells irradiated with iron ions, but not with protons.

Elevated temperature during reproductive development affects cone traits and progeny performance in Picea glauca x engelmannii complex.

PubMed

Webber, Joe; Ott, Peter; Owens, John; Binder, Wolfgang

2005-10-01

Two temperature regimes were applied during reproductive development of seed and pollen cones of interior spruce (Picea glauca (Moench) Voss and Picea engelmannii (Parry) complex) to determine temperature effects on the adaptive traits of progeny. In Experiment 1, identical crosses were made on potted interior spruce using untreated pollen followed by exposure to a day/night temperature of 22/8 or 14/8 degrees C with a 12-h photoperiod during the stages of reproductive development from post-pollination to early embryo development. Frost hardiness and growth of progeny from seed produced in the two temperature treatments were measured over a 4-year period. Elevated temperature significantly affected both seed-cone development and the adaptive properties of the progeny. Seed cones exposed to the 22/8 degrees C treatment reached the early embryo stage in 53 days versus 92 days in the 14/8 degrees C treatment. Seed yields, cotyledon emergence and percent germination were also significantly enhanced by the 22/8 degrees C treatment. Progeny from seed produced in the higher temperature treatment showed significantly reduced spring and fall frost hardiness, but the elevated temperature treatment had no significant effects on time of bud burst, growth patterns or final heights. In Experiment 2, single ramets of the same clone were subjected to a day/night temperature of 20/8 or 10/8 degrees C during pollen cone development, starting from meiosis and ending at pollen shedding. The two populations of pollen were then crossed with untreated seed cones. Compared with pollen cones exposed to the 10/8 degrees C treatment, pollen cones exposed to the 20/8 degrees C treatment during development reached the shedding stage 2-4 weeks earlier, whereas pollen yields, in vitro viability and fertility (seed set) were significantly lower; however, the resulting progeny displayed no treatment differences in frost hardiness or growth after 1 year. Results suggest that seed orchard after

Alterations and Abnormal Mitosis of Wheat Chromosomes Induced by Wheat-Rye Monosomic Addition Lines

PubMed Central

Fu, Shulan; Yang, Manyu; Fei, Yunyan; Tan, Feiquan; Ren, Zhenglong; Yan, Benju; Zhang, Huaiyu; Tang, Zongxiang

2013-01-01

Background Wheat-rye addition lines are an old topic. However, the alterations and abnormal mitotic behaviours of wheat chromosomes caused by wheat-rye monosomic addition lines are seldom reported. Methodology/Principal Findings Octoploid triticale was derived from common wheat T. aestivum L. ‘Mianyang11’×rye S. cereale L. ‘Kustro’ and some progeny were obtained by the controlled backcrossing of triticale with ‘Mianyang11’ followed by self-fertilization. Genomic in situ hybridization (GISH) using rye genomic DNA and fluorescence in situ hybridization (FISH) using repetitive sequences pAs1 and pSc119.2 as probes were used to analyze the mitotic chromosomes of these progeny. Strong pSc119.2 FISH signals could be observed at the telomeric regions of 3DS arms in ‘Mianyang11’. However, the pSc119.2 FISH signals were disappeared from the selfed progeny of 4R monosomic addition line and the changed 3D chromosomes could be transmitted to next generation stably. In one of the selfed progeny of 7R monosomic addition line, one 2D chromosome was broken and three 4A chromosomes were observed. In the selfed progeny of 6R monosomic addition line, structural variation and abnormal mitotic behaviour of 3D chromosome were detected. Additionally, 1A and 4B chromosomes were eliminated from some of the progeny of 6R monosomic addition line. Conclusions/Significance These results indicated that single rye chromosome added to wheat might cause alterations and abnormal mitotic behaviours of wheat chromosomes and it is possible that the stress caused by single alien chromosome might be one of the factors that induced karyotype alteration of wheat. PMID:23936213

Assessment of Inhibition of Ebola Virus Progeny Production by Antiviral Compounds.

PubMed

Falzarano, Darryl

2017-01-01

Assessment of small molecule compounds against filoviruses, such as Ebola virus, has identified numerous compounds that appear to have antiviral activity and should presumably be further investigated in animal efficacy trials. However, despite the many compounds that are purported to have good antiviral activity in in vitro studies, there are few instances where any efficacy has been reported in nonhuman primate models. Many of the high-throughput screening assays use reporter systems that only recapitulate a portion of the virus life cycle, while other assays only assess antiviral activity at relatively early time points. Moreover, many assays do not assess virus progeny production. A more in-depth evaluation of small numbers of test compounds is useful to economize resources and to generate higher quality antiviral hits. Assessing virus progeny production as late as 5 days post-infection allows for the elimination of compounds that have initial antiviral effects that are not sustained or where the virus rapidly develops resistance. While this eliminates many potential lead compounds that may be worthy of further structure-activity relationship (SAR) development, it also quickly excludes compounds that in their current form are unlikely to be effective in animal models. In addition, the inclusion of multiple assays that assess both cell viability and cell cytotoxicity, via different mechanisms, provides a more thorough assessment to exclude compounds that are not direct-acting antivirals.

Repeatability of number of progeny born to bulls used in group mating of cows

USDA-ARS?s Scientific Manuscript database

The group mating of bulls in pasture situations is a management practice that might be more efficient if an individual bull’s ability to sire calves could be predicted. Retrospective data on numbers of progeny born to bulls from 4 populations (Angus and 3 composite breeds) in 4 consecutive years of...

Purification of Immature Neuronal Cells from Neural Stem Cell Progeny

PubMed Central

Azari, Hassan; Osborne, Geoffrey W.; Yasuda, Takahiro; Golmohammadi, Mohammad G.; Rahman, Maryam; Deleyrolle, Loic P.; Esfandiari, Ebrahim; Adams, David J.; Scheffler, Bjorn; Steindler, Dennis A.; Reynolds, Brent A.

2011-01-01

Large-scale proliferation and multi-lineage differentiation capabilities make neural stem cells (NSCs) a promising renewable source of cells for therapeutic applications. However, the practical application for neuronal cell replacement is limited by heterogeneity of NSC progeny, relatively low yield of neurons, predominance of astrocytes, poor survival of donor cells following transplantation and the potential for uncontrolled proliferation of precursor cells. To address these impediments, we have developed a method for the generation of highly enriched immature neurons from murine NSC progeny. Adaptation of the standard differentiation procedure in concert with flow cytometry selection, using scattered light and positive fluorescent light selection based on cell surface antibody binding, provided a near pure (97%) immature neuron population. Using the purified neurons, we screened a panel of growth factors and found that bone morphogenetic protein-4 (BMP-4) demonstrated a strong survival effect on the cells in vitro, and enhanced their functional maturity. This effect was maintained following transplantation into the adult mouse striatum where we observed a 2-fold increase in the survival of the implanted cells and a 3-fold increase in NeuN expression. Additionally, based on the neural-colony forming cell assay (N-CFCA), we noted a 64 fold reduction of the bona fide NSC frequency in neuronal cell population and that implanted donor cells showed no signs of excessive or uncontrolled proliferation. The ability to provide defined neural cell populations from renewable sources such as NSC may find application for cell replacement therapies in the central nervous system. PMID:21687800

Occurrence of dsRNA Mycovirus (LeV-FMRI0339) in the Edible Mushroom Lentinula edodes and Meiotic Stability of LeV-FMRI0339 among Monokaryotic Progeny

PubMed Central

Kim, Jung-Mi; Yun, Suk-Hyun; Park, Seung-Moon; Ko, Han-Gyu; Kim, Dae-Hyuk

2013-01-01

dsRNA was found in malformed cultures of Lentinula edodes strain FMRI0339, one of the three most popular sawdust cultivated commercial strains of shiitake, and was also found in healthy-looking fruiting bodies and actively growing mycelia. Cloning of the partial genome of the dsRNA revealed the presence of the RdRp sequence of a novel L. edodes mycovirus (LeV), and sequence comparison of the cloned amplicon showed identical sequences sequence to known RNA-dependent RNA polymerase genes of LeV found in strain HKA. The meiotic stability of dsRNA was examined by measuring the ratio of the presence of dsRNA among sexual monokaryotic progeny. More than 40% of the monokaryotic progeny still contained the dsRNA, indicating the persistence of dsRNA during sexual reproduction. Comparing the mycelia growth of monokaryotic progeny suggested that there appeared to be a tendency toward a lower frequency of virus incidence in actively growing progeny. PMID:25288977

The portable device for continual measurement of radon progenies on filter using the detector Timepix.

PubMed

Bulanek, Boris; Hulka, Jiri; Jilek, Karel; Stekl, Ivan

2015-06-01

In this article, a portable device was presented for continual measuring of equilibrium equivalent concentration (EEC) of (222)Rn based on the Timepix detector with 300-µm-thick active layer. In order to have a portable device, a filtration head was developed for collecting short-lived radon progenies attached on aerosols. The short-lived progenies are estimated from analysing alphas from decay of (218,214)Po from Millipore filter after termination of filtration. Comparison with beta measurement was done as well. The dependence of EEC on an air flow and filtration time was studied. The low-level detection limit for EEC was estimated from the last 10 min of 3-h decay measurement and was found in the range of 40-70 Bq m(-3). EEC was measured in National Radiation Protection Institute radon chamber, and results were compared with the commercial detector Fritra4. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Sex determination in beetles: Production of all male progeny by Parental RNAi knockdown of transformer

PubMed Central

Shukla, Jayendra Nath; Palli, Subba Reddy

2012-01-01

Sex in insects is determined by a cascade of regulators ultimately controlling sex-specific splicing of a transcription factor, Doublesex (Dsx). We recently identified homolog of dsx in the red flour beetle, Tribolium castaneum (Tcdsx). Here, we report on the identification and characterization of a regulator of Tcdsx splicing in T. castaneum. Two male-specific and one female-specific isoforms of T. castaneum transformer (Tctra) were identified. RNA interference-aided knockdown of Tctra in pupa or adults caused a change in sex from females to males by diverting the splicing of Tcdsx pre-mRNA to male-specific isoform. All the pupa and adults developed from Tctra dsRNA injected final instar larvae showed male-specific sexually dimorphic structures. Tctra parental RNAi caused an elimination of females from the progeny resulting in production of all male progeny. Transformer parental RNAi could be used to produce all male population for use in pest control though sterile male release methods. PMID:22924109

Genetic stability of progeny from an artificial allotetraploid carp using sperm from five fish species.

PubMed

Ye, Yuzhen; Wang, Zhongwei; Zhou, Jianfeng; Wu, Qingjiang

2009-08-01

Microsatellite markers and D-loop sequences of mtDNA from a female allotetraploid parent carp and her progenies of generations 1 and 2 induced by sperm of five distant fish species were analyzed. Eleven microsatellite markers were used to identify 48 alleles from the allotetraploid female. The same number of alleles (48) appeared in the first and second generations of the gynogenetic offspring, regardless of the source of the sperm used as an activator. The mtDNA D-loop analysis was performed on the female tetraploid parent, 25 gynogenetic offspring, and 5 sperm-donor species. Fourteen variable sites from the 1,018 bp sequences were observed in the offspring as compared to the female tetraploid parent. Results from D-loop sequence and microsatellite marker analysis showed exclusive maternal transmission, and no genetic information was derived from the father. Our study suggests that progenies of artificial tetraploid carp are genetically stable, which is important for genetic breeding of this tetraploid fish.

Hypoxia Treatment of Callosobruchus maculatus Females and Its Effects on Reproductive Output and Development of Progeny Following Exposure.

PubMed

Yan, Yan; Williams, Scott B; Baributsa, Dieudonne; Murdock, Larry L

2016-06-17

Modified atmospheres present a residue-free alternative to fumigants for controlling postharvest pests of grain during storage. How sub-lethal applications of this method affects the reproductive fitness of target pests, however, is still not fully understood. We examined how low levels of ambient oxygen influence the reproduction of the female cowpea bruchid (Callosobruchus maculatus), a pest of cowpea. We used three low-oxygen atmospheres-2%, 5% and 10% (v/v) oxygen-and observed their effects on: (1) the number of eggs laid by bruchids compared to insects held in normoxic (~20% oxygen) conditions; (2) the total number of eggs laid; and (3) the number of progeny that reached maturity. Low oxygen did not significantly affect the number of eggs laid during 48 or 72 h of exposure, but 2% and 5% oxygen did negatively affected total egg production. Increasing the exposure time from 48 to 72 h further depressed lifetime reproductive output. Maternal and egg exposure to hypoxia reduced the number of progeny that reached adulthood. Lower adult emergence was observed from eggs laid under low oxygen and longer exposure times. These data demonstrate that hermetic conditions depress the egg-laying behavior of cowpea bruchids and the successful development of their progeny.

Hypoxia Treatment of Callosobruchus maculatus Females and Its Effects on Reproductive Output and Development of Progeny Following Exposure

PubMed Central

Yan, Yan; Williams, Scott B.; Baributsa, Dieudonne; Murdock, Larry L.

2016-01-01

Modified atmospheres present a residue-free alternative to fumigants for controlling postharvest pests of grain during storage. How sub-lethal applications of this method affects the reproductive fitness of target pests, however, is still not fully understood. We examined how low levels of ambient oxygen influence the reproduction of the female cowpea bruchid (Callosobruchus maculatus), a pest of cowpea. We used three low-oxygen atmospheres—2%, 5% and 10% (v/v) oxygen—and observed their effects on: (1) the number of eggs laid by bruchids compared to insects held in normoxic (~20% oxygen) conditions; (2) the total number of eggs laid; and (3) the number of progeny that reached maturity. Low oxygen did not significantly affect the number of eggs laid during 48 or 72 h of exposure, but 2% and 5% oxygen did negatively affected total egg production. Increasing the exposure time from 48 to 72 h further depressed lifetime reproductive output. Maternal and egg exposure to hypoxia reduced the number of progeny that reached adulthood. Lower adult emergence was observed from eggs laid under low oxygen and longer exposure times. These data demonstrate that hermetic conditions depress the egg-laying behavior of cowpea bruchids and the successful development of their progeny. PMID:27322332

Maternal Transfer of Vitamin C in Channel Catfish (Ictalurus Punctatus) Effects Reproduction and Progeny Performance

USDA-ARS?s Scientific Manuscript database

Two routes of maternal transfer of vitamin C in channel catfish female broodfish prior to spawning were explored as a strategy to incorporate the vitamin to determine its effect on reproduction and subsequent performance of the progeny. Accumulation of vitamin C was higher (p<0.05) in ovarian tissu...

Genetic analyses of endoreduplication in Zea mays endosperm: evidence of sporophytic and zygotic maternal control.

PubMed

Dilkes, Brian P; Dante, Ricardo A; Coelho, Cintia; Larkins, Brian A

2002-03-01

Flow cytometry was used to assess the variability of endoreduplication in endosperms of maize inbred lines. Little variation was found between midwestern dent types, and high levels of endoreduplication were observed in popcorns. Endoreduplication is different between inbred lines by 13-18 days after pollination, and flow cytometric analysis of ploidy level was feasible until 20 DAP. To study the genetic regulation of endoreduplication, four inbreds were crossed to B73 and developing endosperms from both parental, reciprocal F(1), and backcross generations were subjected to flow cytometric analysis. Three measurements of endoreduplication were calculated from these data and analyzed as quantitative genetic traits. Multiple models of trait inheritance were considered including triploid, diploid, sporophytic maternal, and maternal and paternal zygotic nuclear inheritance. Maternal zygotic effects, often considered a form of parental imprinting, and maternal sporophytic effects were detected. To test the feasibility of introgressing a high endoreduplication phenotype into a midwestern dent inbred line, a backcross population was generated from B73 x Sg18. Parental and progeny endoreduplication levels were compared and heritabilities assessed. The heritabilities calculated from these data generally agree with the values calculated in the larger crossing experiments.

Genetic changes in progeny of bystander human fibroblasts after microbeam irradiation with X-rays, protons or carbon ions: the relevance to cancer risk.

PubMed

Autsavapromporn, Narongchai; Plante, Ianik; Liu, Cuihua; Konishi, Teruaki; Usami, Noriko; Funayama, Tomoo; Azzam, Edouard I; Murakami, Takeshi; Suzuki, Masao

2015-01-01

Radiation-induced bystander effects have important implications in radiotherapy. Their persistence in normal cells may contribute to risk of health hazards, including cancer. This study investigates the role of radiation quality and gap junction intercellular communication (GJIC) in the propagation of harmful effects in progeny of bystander cells. Confluent human skin fibroblasts were exposed to microbeam radiations with different linear energy transfer (LET) at mean absorbed doses of 0.4 Gy by which 0.036-0.4% of the cells were directly targeted by radiation. Following 20 population doublings, the cells were harvested and assayed for micronucleus formation, gene mutation and protein oxidation. Our results showed that expression of stressful effects in the progeny of bystander cells is dependent on LET. The progeny of bystander cells exposed to X-rays (LET ∼6 keV/μm) or protons (LET ∼11 keV/μm) showed persistent oxidative stress, which correlated with increased micronucleus formation and mutation at the hypoxanthine-guanine phosphoribosyl-transferase (HPRT) locus. Such effects were not observed after irradiation by carbon ions (LET ∼103 keV/μm). Interestingly, progeny of bystander cells from cultures exposed to protons or carbon ions under conditions where GJIC was inhibited harbored reduced oxidative and genetic damage. This mitigating effect was not detected when the cultures were exposed to X-rays. These findings suggest that cellular exposure to proton and heavy charged particle with LET properties similar to those used here can reduce the risk of lesions associated with cancer. The ability of cells to communicate via gap junctions at the time of irradiation appears to impact residual damage in progeny of bystander cells.

Vernalization response of domesticated× wild chickpea progeny is subject to strong genotype by environment interaction

USDA-ARS?s Scientific Manuscript database

Vernalization insensitivity is a key feature of domesticated chickpea and its genetic basis is not well understood. We studied vernalization response among hybrid progeny derived from two domesticated x wild crosses. The wild parents are vernalization sensitive, late flowering genotypes while both d...

[Assessment of the impact of GMO of plant origin on rat progeny development in 3 generations].

PubMed

Tyshko, N V; Zhminchenko, V M; Pashorina, V A; Seliaskin, K E; Saprykin, V P; Utembaeva, N T; Tutel'ian, V A

2011-01-01

The publication presents the results of assessment of impact of genetically modified (GM) maize Liberty Link on prenatal and postnatal development of progeny of 3 generations of Wistar rats. A total of 630 adult animals and 2837 pups were used in the experiment. The animals were divided into 5 groups which got the diets with inclusion of maize: the animals of the experimental group got the diet with the GM-maize, animals of the control group - with near isogenic conventional analogue of the GM-maize, animals of the 1st, 2nd and 3rd reference groups - conventional varieties of maize ROSS 144 MV, ROSS 197 MVW, Dokuchayevskaya 250 MV respectively. The maize was included in the diet at maximum possible level not violating the balance of basic nutrients. Analysis of the data obtained during the study did not reveal any impact of GM-maize on rat progeny development.

RADON PROGENY AS AN EXPERIMENTAL TOOL FOR DOSIMETRY OF NANOAEROSOLS

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

Ruzer, Lev; Ruzer, Lev S.; Apte, Michael G.

2008-02-25

The study of aerosol exposure and dosimetry measurements and related quantitation of health effects are important to the understanding of the consequences of air pollution, and are discussed widely in the scientific literature. During the last 10 years the need to correlate aerosol exposure and biological effects has become especially important due to rapid development of a new, revolutionary industry ?-- nanotechnology. Nanoproduct commerce is predicted to top $1 trillion by 2015. Quantitative assessment of aerosol particle behavior in air and in lung deposition, and dosimetry in different parts of the lung, particularly for nanoaerosols, remains poor despite several decadesmore » of study. Direct measurements on humans are still needed in order to validate the hollow cast, animal studies, and lung deposition modeling. We discuss here the use of nanoscale radon decay products as an experimental tool in the study of local deposition and lung dosimetry for nanoaerosols. The issue of the safe use of radon progeny in such measurements is discussed based on a comparison of measured exposure in 3 settings: general population, miners, and in a human experiment conducted at the Paul Scherer Institute (PSI) in Switzerland. One of the properties of radon progeny is that they consist partly of 1 nm radioactive particles called unattached activity; having extremely small size and high diffusion coefficients, these particles can be potentially useful as radioactive tracers in the study of nanometer-sized aerosols. We present a theoretical and experimental study of the correlation between the unattached activity and aerosol particle surface area, together with a description of its calibration and method for measurement of the unattached fraction.« less

Progeny Review: An Alternative Approach for Examining the Replication of Intervention Studies in Special Education

ERIC Educational Resources Information Center

Therrien, William J.; Mathews, Hannah M.; Hirsch, Shanna Eisner; Solis, Michael

2016-01-01

Despite the importance of replication for building an evidence base, there has been no formal examination to date of replication research in special education. In this review, we examined the extent and nature of replication of intervention research in special education using an "article progeny" approach and a three-pronged definition…

Inheritance mode and realized heritability of resistance to imidacloprid in the brown planthopper, Nilaparvata lugens (Stål) (Homoptera: Delphacidae).

PubMed

Wang, Yan Hua; Liu, Xu Gan; Zhu, Yu Cheng; Wu, Sheng Gan; Li, Shu Yong; Chen, Wen Ming; Shen, Jin Liang

2009-06-01

The brown planthopper, Nilaparvata lugens (Stål), is a serious pest that causes enormous losses to the rice crop in Asia. The genetic basis of imidacloprid resistance was investigated in N. lugens. The resistant strain, selected for imidacloprid resistance from a field population of N. lugens collected from Nanjing, Jiangsu Province, China, showed a 964-fold resistance compared with the laboratory strain. Progenies of reciprocal crosses (F(1) and F(1)') showed similar dose-mortality responses (LC(50)) to imidacloprid, and also exhibited a similar degree of dominance (D), 0.58 for F(1) and 0.63 for F(1)'. Chi-square analyses of self-bred and backcross progenies (F(2), F(2)' and BC respectively) rejected the hypothesis for a single gene control of the resistance. The estimated realized heritability (h(2)) of imidacloprid resistance was 0.1141 in the resistant strain of N. lugens. The results showed that imidacloprid resistance in N. lugens was autosomal and was expressed as an incompletely dominant trait, probably controlled by multiple genes.

Mapping Quantitative Field Resistance Against Apple Scab in a 'Fiesta' x 'Discovery' Progeny.

PubMed

Liebhard, R; Koller, B; Patocchi, A; Kellerhals, M; Pfammatter, W; Jermini, M; Gessler, C

2003-04-01

ABSTRACT Breeding of resistant apple cultivars (Malus x domestica) as a disease management strategy relies on the knowledge and understanding of the underlying genetics. The availability of molecular markers and genetic linkage maps enables the detection and the analysis of major resistance genes as well as of quantitative trait loci (QTL) contributing to the resistance of a genotype. Such a genetic linkage map was constructed, based on a segregating population of the cross between apple cvs. Fiesta (syn. Red Pippin) and Discovery. The progeny was observed for 3 years at three different sites in Switzerland and field resistance against apple scab (Venturia inaequalis) was assessed. Only a weak correlation was detected between leaf scab and fruit scab. A QTL analysis was performed, based on the genetic linkage map consisting of 804 molecular markers and covering all 17 chromosomes of apple. With the maximum likelihood-based interval mapping method, eight genomic regions were identified, six conferring resistance against leaf scab and two conferring fruit scab resistance. Although cv. Discovery showed a much stronger resistance against scab in the field, most QTL identified were attributed to the more susceptible parent 'Fiesta'. This indicated a high degree of homozygosity at the scab resistance loci in 'Discovery', preventing their detection in the progeny due to the lack of segregation.

A correlation of long term effects and radiation quality in the progeny of bystander cells after microbeam radiations: The experimental study of radiotherapy for cancer risk mitigation

NASA Astrophysics Data System (ADS)

Autsavapromporn, N.; Konishi, T.; Liu, C.; Plante, I.; Funayama, T.; Usami, N.; Azzam, EI; Suzuki, M.

2017-06-01

The goal of this study is to investigate the role of radiation quality and gap junction intercellular communication (GJIC) in the propagation of delayed stressful effects in the progeny of bystander human skin fibroblasts cultures (NB1RGB). Briefly, confluent NB1RGB cells in the presence and absence of gap junction inhibitor (AGA) were exposed to ionizing radiation (IR) with a different linear energy transfer (LET) either 5.35 keV X rays (LET ∼6 keV/μm) or 18.3 MeV/u carbon (LET ∼103 keV/μm) microbeam radiations. Following 20 populations post-irradiation, the progeny of bystander NB1RGB cells were harvested and assayed for several of biological endpoints. Our results showed that expression of stressful effects in the progeny of bystander cells is dependent on LET. The progeny of bystander cells exposed to low-LET X rays showed the persistence of oxidative stress and it was correlated with the increased mutant fraction. Such effect were not observed after high-LET carbon ions. Interestingly, inhibition of GJIC mitigated the toxic effects in the progeny of bystander cells. Together, the results contribute to the understanding of the fundamental radiation biology relating to the high-LET carbon ions to mitigate cancer risk after radiotherapy. Furthermore, GJIC be considered as a critical mediator in the bystander mutagenic effect.

Recent Natural Hybridization between Two Allopolyploid Wheatgrasses (Elytrigia, Poaceae): Ecological and Evolutionary Implications

PubMed Central

Mahelka, Václav; Fehrer, Judith; Krahulec, František; Jarolímová, Vlasta

2007-01-01

Background and Aims Natural hybridization was investigated between two predominantly allohexaploid wheatgrasses, weedy Elytrigia repens and steppic E. intermedia, with respect to habitats characterized by different degrees of anthropogenic disturbance. Methods Using flow cytometry (relative DNA content), 269 plants from three localities were analysed. Hybrids were further analysed using nuclear ribosomal (ITS1-5·8S-ITS2 region) and chloroplast (trnT-F region) DNA markers in addition to absolute DNA content and chromosome numbers. Key Results Weedy E. repens was rare in a steppic locality whereas E. intermedia was almost absent at two sites of agricultural land-use. Nevertheless, hybrids were common there whereas none were found at the steppic locality, underlining the importance of different ecological conditions for hybrid formation or establishment. At one highly disturbed site, > 16 % of randomly collected plants were hybrids. Hexaploid hybrids showed intermediate genome size compared with the parents and additive patterns of parental ITS copies. Some evidence of backcrosses was found. The direction of hybridization was highly asymmetric as cpDNA identified E. intermedia as the maternal parent in 61 out of 63 cases. Out of nine nonaploid cytotypes (2n = 9x = 63) which likely originated by fusion of unreduced and reduced gametes of hexaploids, eight were hybrids whereas one was a nonaploid cytotype of E. repens. The progeny of one nonaploid hybrid demonstrated gene flow between hexaploid and nonaploid cytotypes. Conclusions The results show that E. repens and E. intermedia frequently cross at places where they co-occur. Hybrid frequency is likely influenced by habitat type; sites disturbed by human influence sustain hybrid formation and/or establishment. Hexaploid and nonaploid hybrid fertility is not negligible, backcrossing is possible, and the progeny is variable. The frequent production of new at least partially fertile cyto- and genotypes provides ample raw

Inheritance of Diapause in Crosses between the Northernmost and the Southernmost Strains of the Asian Corn Borer Ostrinia furnacalis

PubMed Central

Fu, Shu; Chen, Chao; Xiao, Liang; He, Haimin; Xue, Fangsen

2015-01-01

The northernmost Harbin strain (N strain) of the Asian corn borer, Ostrinia furnacalis enters facultative diapause as fully grown larvae in response to short daylengths; whereas the southernmost Ledong strain (S strain) exhibits almost no diapause under the same light conditions. In the present study, we examined the inheritance of diapause induction and termination by crossing the two strains under a range of environmental conditions. The N strain showed a typical long-day response with a critical daylength of approximately15.88 h at 22°C, 15.72 h at 25°C and 15.14 h at 28°C, whereas the S strain showed a weak photoperiodic response at 22°C. The F1 progeny also showed a long-day response at 22, 25 and 28°C. However, the critical daylengths in S ♀ × N ♂ crosses were significantly longer than those in N ♀ × S ♂ crosses, indicating a sex linkage in the inheritance of diapause induction, with the male parent having more influence on the following F1 progeny. The incidence of diapause in S ♀ × N ♂ crosses was the same as in the N strain under short daylengths of 11-13 h, indicating that diapause trait is completely dominant over the non-diapause trait. The critical daylength in backcross to N was significantly longer than it was in backcross to S, showing a grandfather gene effect. Whether the inheritance of diapause fits an additive hypothesis or not was dependent on the rearing photoperiod, and the capacity for diapause was transmitted genetically in the manner of incomplete dominance. The duration of diapause for the reciprocal crosses under different diapause-terminating conditions showed different patterns of inheritance. The results in this study reveal that genetic and genetic-environmental interactions are involved in diapause induction and termination in O. furnacalis. PMID:25706525

Delayed persistence of giant-nucleated cells induced by X-ray and proton irradiation in the progeny of replicating normal human f ibroblast cells

NASA Astrophysics Data System (ADS)

Almahwasi, A. A.; Jeynes, J. C.; Merchant, M. J.; Bradley, D. A.; Regan, P. H.

2017-08-01

Ionising radiation can induce giant-nucleated cells (GCs) in the progeny of irradiated populations, as demonstrated in various cellular systems. Most in vitro studies have utilised quiescent cancerous or normal cell lines but it is not clear whether radiation-induced GCs persist in the progeny of normal replicated cells. In the current work we show persistent induction of GCs in the progeny of normal human-diploid skin fibroblasts (AG1522). These cells were originally irradiated with a single equivalent clinical dose of 0.2, 1 or 2 Gy of either X-ray or proton irradiation and maintained in an active state for various post-irradiation incubation interval times before they were replated for GC analysis. The results demonstrate that the formation of GCs in the progeny of X-ray or proton irradiated cells was increased in a dose-dependent manner when measured 7 days after irradiation and this finding is in agreement with that reported for the AG1522 cells using other radiation qualities. For the 1 Gy X-ray doses it was found that the GC yield increased continually with time up to 21 days post-irradiation. These results can act as benchmark data for such work and may have important implications for studies aimed at evaluating the efficacy of radiation therapy and in determining the risk of delayed effects particularly when applying protons.

Characteristics of indoor radon and its progeny in a Japanese dwelling while using air appliances.

PubMed

Pornnumpa, C; Tokonami, S; Sorimachi, A; Kranrod, C

2015-11-01

Characteristics of radon and its progeny were investigated in different air conditions by turning four types of indoor air appliances on and off in a two-story concrete Japanese dwelling. The four appliances were air conditioner, air cleaner, gas heater and cooker hood. The measurements were done using two devices: (1) a Si-based semiconductor detector for continuous measurement of indoor radon concentration and (2) a ZnS(Ag) scintillation counting system for equilibrium-equivalent radon concentration. Throughout the entire experiment, the cooker hood was the most effective in decreasing indoor radon concentration over a long period of time and the less effective was the air conditioner, while the air cleaner and gas heater did not affect the concentration of radon. However, the results measured in each air condition will differ according to the lifestyles and activities of the inhabitants. In this study, indoor radon and its progeny in a Japanese dwelling will be characterised by the different air conditions. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Death losses due to stillbirth, neonatal death and diseases in cloned cattle derived from somatic cell nuclear transfer and their progeny: a result of nationwide survey in Japan.

PubMed

Watanabe, Shinya; Nagai, Takashi

2009-06-01

To obtain the data concerning death losses due to stillbirth, neonatal death and diseases in cloned cattle derived from somatic cell nuclear transfer (SCNT) and their progeny produced by Japanese institutions, a nationwide survey was carried out in July-August, 2006. As a result, lifetime data concerning 482 SCNT cattle (97.5% of cattle produced in the country at that time) and 202 progeny of SCNT cattle were accumulated and the death loss of these cattle was analyzed. Although 1/3 of delivered SCNT calves died during the perinatal period due to stillbirth and neonatal death, incidence of death loss due to diseases in SCNT cattle surviving more than 200 days after birth seems to be the same as these in conventionally bred cattle. In contrast, progeny of SCNT cattle showed the same level in death loss as observed in conventionally bred cattle throughout their lifetime. These results suggest that robust health would be expected in SCNT cattle surviving to adulthood and their progeny.

Height and diameter variation in twelve white ash provenance/progeny tests in eastern United States

Treesearch

G. Rink; F.H. Kung

1991-01-01

Results from 12- and 13-year old rangewide provenance/progeny tests of white ash (Fraxinus americana L.) planted at 12 locations throughout the eastern United States are reported. Although heritability of white ash tree height and dbh is high at both the provenance and family levels, the trend in variance components is for increasing provenance and...

Field levels of infection of progenies of western white pines selected for blister rust resistance

Treesearch

R. J. Steinhoff

1971-01-01

Western white pine trees resulting from crosses of parents selected for phenotypic resistance to Cronartium ribicola J. C. Fisch. ex Rabenh., the white pine blister rust, were inspected for rust infection after 11 to 15 years in two field plots. When compared to controls and to natural reproduction, the progenies of crosses involving trees that exhibited general...

Temporal variability of the quality of Taraxacum officinale seed progeny from the East-Ural radioactive trace: is there an interaction between low level radiation and weather conditions?

PubMed

Pozolotina, Vera N; Antonova, Elena V

2017-03-01

The multiple stressors, in different combinations, may impact differently upon seed quality, and low-level doses of radiation may enhance synergistic or antagonistic effects. During 1991-2014 we investigated the quality of the dandelion (Taraxacum officinale s.l.) seed progeny growing under low-level radiation exposure at the East-Ural Radioactive Trace (EURT) area (result of the Kyshtym accident, Russia), and in plants from areas exposed to background radiation. The viability of the dandelion seed progeny was assessed according to chronic radiation exposure, accounting for the variability of weather conditions among years. Environmental factors (temperature, precipitation, and their ratio in different months) can modify the radiobiological effects. We found a wide range of possible responses to multiple stressors: inhibition, stimulation, and indifferent effects in different seasons. The intraspecific variability of the quality of dandelion seed progeny was greatly increased under conditions of low doses of chronic irradiation. Temperature was the most significant factor for seed progeny formation in the EURT zone, whereas the sums of precipitation and ratios of precipitation to temperature dominantly affected organisms from the background population.

Genetic variation of an acid phosphatase (Acp-2) in the laboratory rat: possible homology with mouse AP-1 and human ACP2.

PubMed

Bender, K; Bissbort, S; Kuhn, A; Nagel, M; Günther, E

1986-02-01

A genetic locus controlling the electrophoretic mobility of an acid phosphatase in the rat (Rattus norvegicus) is described. The locus, designed Acp-2, is not expressed in erythrocytes but is expressed in all other tissues studied. The product of Acp-2 hydrolyzes a wide variety of phosphate monoesters and is inhibited by L(+)-tartaric acid. Inbred rat strains have fixed either allele Acp-2a or allele Acp-2b. Codominant expression is observed in the respective F1 hybrids. Backcross progenies revealed the expected 1:1 segregation ratio. Possible loose linkage was found between the Acp-2 and the Pep-3 gene loci at a recombination frequency of 0.36 +/- 0.06.

Intercomparison of active, passive and continuous instruments for radon and radon progeny measurements in the EML chamber and test facility

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

Scarpitta, S.C.; Tu, K.W.; Fisenne, I.M.

1996-10-01

Results are presented from the Fifth Intercomparison of Active, Passive and Continuous Instruments for Radon and Radon Progeny Measurements conducted in the EML radon exposure and test facility in May 1996. In total, thirty-four government, private and academic facilities participated in the exercise with over 170 passive and electronic devices exposed in the EML test chamber. During the first week of the exercise, passive and continuous measuring devices were exposed (usually in quadruplicate) to about 1,280 Bq m{sup {minus}3} {sup 222}Rn for 1--7 days. Radon progeny measurements were made during the second week of the exercise. The results indicate thatmore » all of the tested devices that measure radon gas performed well and fulfill their intended purpose. The grand mean (GM) ratio of the participants` reported values to the EML values, for all four radon device categories, was 0.99 {plus_minus} 0.08. Eighty-five percent of all the radon measuring devices that were exposed in the EML radon test chamber were within {plus_minus}1 standard deviation (SD) of the EML reference values. For the most part, radon progeny measurements were also quite good as compared to the EML values. The GM ratio for the 10 continuous PAEC instruments was 0.90 {plus_minus} 0.12 with 75% of the devices within 1 SD of the EML reference values. Most of the continuous and integrating electronic instruments used for measuring the PAEC underestimated the EML values by about 10--15% probably because the concentration of particles onto which the radon progeny were attached was low (1,200--3,800 particles cm{sup {minus}3}). The equilibrium factor at that particle concentration level was 0.10--0.22.« less

Morphometric abnormalities in spleen and kidney of the progeny of mice fed American cranberry extract (Vaccinium macrocarpon) during pregnancy and lactation.

PubMed

Bałan, B J; Lewicki, S; Siwicki, A K; Stelmasiak, M; Skopiński, P; Skopińska-Różewska, E; Wasiutyński, A; Zdanowski, R

2017-03-28

Cranberries and cranberry-derived diet supplements are often recommended for the treatment of urinary tract infections, also during pregnancy. These products contain strongly anti-angiogenic chemical compounds which could not be indifferent to the developing fetus. In the present work we evaluated the effect of feeding pregnant and lactating mice American cranberry extract (daily dose 0.88 mg) on the morphology and some parameters of spleen and kidney function of their adult progeny. Six weeks after delivery the morphometry of spleen and kidney, cytometric analysis of spleen lymphocytes, evaluation of humoral response to SRBC (Sheep Red Blood Cells), and examination of serum creatinine/urea concentration, were performed in the offspring. Spleens of progeny from experimental (E) group differed from the spleens of progeny of control mice in the lower number of lymphatic nodules and their larger diameter. Cytometry of spleen cells from progeny of E mothers revealed more CD19+ and CD8+ lymphocytes than in the control group. No difference was seen in the response to immunization by red blood cells of sheep (SRBC) between control and E offspring. An increase in the diameter of glomeruli was observed in the kidneys of the experimental group in comparison with the control group. No abnormalities in creatinine and urea serum level were observed. A higher concentration of VEGF and bFGF in E offspring sera in comparison to the controls was seen. Although the observed differences between the control and experimental group were not large, caution is recommended in using cranberries and their extracts during pregnancy until more research will be done on this topic.

Enhancement of Chlamydia trachomatis infectious progeny by cultivation of HeLa 229 cells treated with DEAE-dextran and cycloheximide.

PubMed Central

Sabet, S F; Simmons, J; Caldwell, H D

1984-01-01

The effects of DEAE-dextran and cycloheximide on the infection of HeLa 229 cells with Chlamydia trachomatis serotype G were studied in terms of the number of cells infected and the yield of infectious progeny per infected cell. Pretreatment of the host cells with DEAE-dextran resulted in an increase in the number of infected cels but had no significant effect on the yield of infectious progeny per infected cell (burst size). In contrast, the addition of cycloheximide to the medium of infected cells had no significant effect on the number of infected cells but greatly enhanced the burst size. The burst size was calculated to be close to 500. The enhanced burst size was also observed in cells treated with DEAE-dextran and cycloheximide. In addition, there was an increase in the number of cells infected and an augmentation of the infectious progeny yield. Under the conditions of combined treatment, the yield of C. trachomatis serotype G cultivated in HeLa 229 cells was found to be approximately threefold higher than the yield of the organisms cultivated in McCoy cells. The results suggest that HeLa 229 cells treated with DEAE-dextran and cycloheximide offer a most suitable system for the high-yield cultivation of C. trachomatis organisms and possibly also for the diagnosis of infection with these organisms. Images PMID:6208215

Superparasitism, immune response and optimum progeny yield in the gregarious parasitoid Palmistichus elaeisis.

PubMed

de S Pereira, Kleber; Guedes, Nelsa Maria P; Serrão, José E; Zanuncio, José C; Guedes, Raul Narciso C

2017-06-01

The subsequent deposition of an egg clutch by a female parasitoid into a host already parasitised either by itself or a conspecific (i.e. superparasitism) is a counterintuitive adaptive strategy, particularly considering the female parasitoid's ability to recognise the parasitised hosts. Such a scenario suggests that the adaptive value of superparasitism depends on the number of clutches laid in the same host, with consequences for parasitoid progeny yield. Here, we tested whether such is the case for the gregarious parasitoid Palmistichus elaeisis and explored its underlying basis. Allowing female parasitoids to lay multiple egg clutches in a single melonworm host pupa, parasitoid progeny and fitness exhibited a peak or optimum at three egg clutches laid per host pupa. In addition, haemocyte count, encapsulation and melanisation decreased with the number of egg clutches laid per host pupa. An optimum number of three clutches laid per host pupa was detected for P. elaeisis. As immune response via haemocyte production, encapsulation and melanisation decreased with the number of clutches laid per host, the higher parasitoid yield and fitness observed is the likely consequence of a compromised immune response coupled with an accommodative (i.e. scramble) larval competitive strategy allowing enough resources for optimum balance of parasitoid number and quality produced. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Chromosome elimination, addition and introgression in intertribal partial hybrids between Brassica rapa and Isatis indigotica

PubMed Central

Tu, Yuqin; Sun, Jian; Ge, Xianhong; Li, Zaiyun

2009-01-01

Background and Aims Partial hybrids with female-parent-type phenotypes and chromosome numbers but altered genomic compositions have been reported in wide crosses of several plants. In order to introgress desirable genes from a wild relative, Isatis indigotica (a dye and medicinal plant; 2n = 14), into Brassica crops, intertribal sexual hybridizations were carried out with B. rapa (2n = 20), and the resulting hybrids and their progenies were characterized. Methods Using genomic in situ hybridization (GISH) and amplified fragment length polymorphism (AFLP), chromosomal/genomic components of the hybrids and their progenies were analysed. Key Results Many hybrid plants were obtained from the mature seeds harvested from the B. rapa × I. indigotica cross, and these exhibited different morphological traits. However, the majority of them did not survive and only three plants grew to maturity. These three hybrids showed poor growth and much smaller stature than the two parents, but had some morphological traits and chemical composition of I. indigotica. One plant had 2n = 10, the haploid chromosome number of B. rapa, and was absolutely sterile. The other two plants had 20 and 22 somatic chromosomes and were male sterile but produced seeds following pollinations with B. rapa. All back-cross progenies over several generations maintained a B. rapa-type phenotype and also displayed some variations in morphological characters and fatty acid compositions. They were all 2n = 20 and showed good seed-set. The hybrid with 2n = 22 produced some progeny plants with 2n = 21 and 2n = 22. GISH detected two chromosomes of I. indigotica in the hybrid with 2n = 22 but none in the one with 2n = 20. AFLP bands specific for I. indigotica, novel for two parents or absent in B. rapa, were detected in the two hybrids and their progenies. These progeny plants were novel B. rapa types with an altered genomic constitution or alien additions. Conclusions Complete or partial chromosome elimination and

Effects of ractopamine and arginine dietary supplementation for sows on growth performance and carcass quality of their progenies.

PubMed

Garbossa, C A P; Carvalho Júnior, F M; Silveira, H; Faria, P B; Schinckel, A P; Abreu, M L T; Cantarelli, V S

2015-06-01

The objective of this study was to evaluate the effects of ractopamine (Rac) and Arg fed to pregnant sows from d 25 to 53 of gestation on fetal muscle development as well as the performance and carcass characteristics of the progeny. One hundred sows were divided into 4 treatments including a control diet, the control plus 1% Arg, the control plus 20 mg/kg Rac, and the control diet supplemented with both additives at the same levels as those used separately. During the farrowing process the data evaluated were the weight of placenta to calculate the placental efficiency and the number of piglets born alive, stillborn, and mummified. To evaluate the fiber number and area, 12 male piglets from each treatment were euthanized to harvest semitendinosus muscle. During the lactation, the preweaning mortality, weaned weights, and number of piglets weaned per litter were evaluated. After weaning, the pig performance was evaluated until the slaughter following the sow treatment. At end of finishing phase, 1 male pig of each treatment replicate was selected to evaluation the carcass and pork quality. All variables measured were analyzed using the MIXED procedure of SAS and least squares means were compared using the Tukey test with P < 0.05. The control diet + supplementation of 1.0% of L-Arg + 20 mg/kg of ractopamine HCl from d 25 to 53 of gestation (Arg+Rac) treatment had a greater number of stillborn piglets (P = 0.014) than the control group. Piglet birth weights from sows fed Rac were 11% greater (P = 0.031) than those of piglets of the control treatment. The semitendinosus muscle fiber diameters of piglets at birth from sows that received Arg, Rac, and Arg+Rac were greater (P < 0.0001) than those of control piglets, and as consequence, the fiber number per square millimeter decreased (P < 0.0001). The final nursery BW of progeny from sows fed Arg and Rac individually were greater (P = 0.010) than those of progeny of the control group. At 110 d of age, in the beginning

Identification of cocoa trees combining high yield potential and resistance to diseases in segregating progenies In Ecuador

USDA-ARS?s Scientific Manuscript database

Diseases and low yielding planting material are the main factors limiting production of “fine” or “flavour” cocoa in Ecuador. This makes it necessary to develop modern varieties capable of overcoming these limitations. During the 1960s and 1970s INIAP tested several progenies from selected crosses...

Milk production and composition, and progeny performance in young ewes with high merit for rapid growth and muscle and fat accumulation.

PubMed

Rosales Nieto, C A; Ferguson, M B; Macleay, C A; Briegel, J R; Wood, D A; Martin, G B; Bencini, R; Thompson, A N

2018-02-26

In ewe lambs, acceleration of growth and accumulation of both muscle and fat leads to earlier sexual maturity and better reproductive performance. The next stage in the development of this theme is to test whether these aspects of growth in young ewes affect milk production in their first lactation and the growth of their first progeny. We studied 75 young Merino ewes that had known phenotypic values for depth of eye muscle (EMD) and fat (FAT), and known Australian Sheep Breeding Values for post-weaning weight (PWT) and depths of eye muscle (PEMD) and fat (PFAT). They lambed for the first time at 1 year of age. Their lambs were weighed weekly from birth to weaning at 10 weeks to determine live weight gain and weaning weight. Progeny birth weight was positively associated with live weight gain and weaning weight (P0.05). The PWT of the sire was positively associated with live weight gain (P0.05). The concentrations of fat, protein, lactose and total solids in the milk were not affected by the phenotype or genotype of the mothers or of the sires of the mothers, or by the sex of the progeny (P>0.05). We conclude that selection of young Merino ewes for better growth, and more rapid accumulation of muscle and fat, will lead to progeny that are heavier at birth, grow faster and are heavier at weaning. Moreover, milk production and composition do not seem to be affected by the genetic merit of the mother for post-weaning live weight or PEMD or PFAT. Therefore, Merino ewes can lamb at 1 year of age without affecting the production objectives of the Merino sheep industry.

Maternal heterozygosity and progeny fitness association in an inbred Scots pine population.

PubMed

Abrahamsson, S; Ahlinder, J; Waldmann, P; García-Gil, M R

2013-03-01

Associations between heterozygosity and fitness traits have typically been investigated in populations characterized by low levels of inbreeding. We investigated the associations between standardized multilocus heterozygosity (stMLH) in mother trees (obtained from12 nuclear microsatellite markers) and five fitness traits measured in progenies from an inbred Scots pine population. The traits studied were proportion of sound seed, mean seed weight, germination rate, mean family height of one-year old seedlings under greenhouse conditions (GH) and mean family height of three-year old seedlings under field conditions (FH). The relatively high average inbreeding coefficient (F) in the population under study corresponds to a mixture of trees with different levels of co-ancestry, potentially resulting from a recent bottleneck. We used both frequentist and Bayesian methods of polynomial regression to investigate the presence of linear and non-linear relations between stMLH and each of the fitness traits. No significant associations were found for any of the traits except for GH, which displayed negative linear effect with stMLH. Negative HFC for GH could potentially be explained by the effect of heterosis caused by mating of two inbred mother trees (Lippman and Zamir 2006), or outbreeding depression at the most heterozygote trees and its negative impact on the fitness of the progeny, while their simultaneous action is also possible (Lynch. 1991). However,since this effect wasn't detected for FH, we cannot either rule out that the greenhouse conditions introduce artificial effects that disappear under more realistic field conditions.

Differential gene expression of wheat progeny with contrasting levels of transpiration efficiency.

PubMed

Xue, Gang-Ping; McIntyre, C Lynne; Chapman, Scott; Bower, Neil I; Way, Heather; Reverter, Antonio; Clarke, Bryan; Shorter, Ray

2006-08-01

High water use efficiency or transpiration efficiency (TE) in wheat is a desirable physiological trait for increasing grain yield under water-limited environments. The identification of genes associated with this trait would facilitate the selection for genotypes with higher TE using molecular markers. We performed an expression profiling (microarray) analysis of approximately 16,000 unique wheat ESTs to identify genes that were differentially expressed between wheat progeny lines with contrasting TE levels from a cross between Quarrion (high TE) and Genaro 81 (low TE). We also conducted a second microarray analysis to identify genes responsive to drought stress in wheat leaves. Ninety-three genes that were differentially expressed between high and low TE progeny lines were identified. One fifth of these genes were markedly responsive to drought stress. Several potential growth-related regulatory genes, which were down-regulated by drought, were expressed at a higher level in the high TE lines than the low TE lines and are potentially associated with a biomass production component of the Quarrion-derived high TE trait. Eighteen of the TE differentially expressed genes were further analysed using quantitative RT-PCR on a separate set of plant samples from those used for microarray analysis. The expression levels of 11 of the 18 genes were positively correlated with the high TE trait, measured as carbon isotope discrimination (Delta(13)C). These data indicate that some of these TE differentially expressed genes are candidates for investigating processes that underlie the high TE trait or for use as expression quantitative trait loci (eQTLs) for TE.

Efficient QTL detection for nonhost resistance in wild lettuce: backcross inbred lines versus F2 population

PubMed Central

Pelgrom, K.; Stam, P.; Lindhout, P.

2008-01-01

In plants, several population types [F2, recombinant inbred lines, backcross inbred lines (BILs), etc.] are used for quantitative trait locus (QTL) analyses. However, dissection of the trait of interest and subsequent confirmation by introgression of QTLs for breeding purposes has not been as successful as that predicted from theoretical calculations. More practical knowledge of different QTL mapping approaches is needed. In this recent study, we describe the detection and mapping of quantitative resistances to downy mildew in a set of 29 BILs of cultivated lettuce (L. sativa) containing genome segments introgressed from wild lettuce (L. saligna). Introgression regions that are associated with quantitative resistance are considered to harbor a QTL. Furthermore, we compare this with results from an already existing F2 population derived from the same parents. We identified six QTLs in our BIL approach compared to only three in the F2 approach, while there were two QTLs in common. We performed a simulation study based on our actual data to help us interpret them. This revealed that two newly detected QTLs in the BILs had gone unnoticed in the F2, due to a combination of recessiveness of the trait and skewed segregation, causing a deficit of the wild species alleles. This study clearly illustrates the added value of extended genetic studies on two different population types (BILs and F2) to dissect complex genetic traits. PMID:18251002

A European-wide 222radon and 222radon progeny comparison study

NASA Astrophysics Data System (ADS)

Schmithüsen, Dominik; Chambers, Scott; Fischer, Bernd; Gilge, Stefan; Hatakka, Juha; Kazan, Victor; Neubert, Rolf; Paatero, Jussi; Ramonet, Michel; Schlosser, Clemens; Schmid, Sabine; Vermeulen, Alex; Levin, Ingeborg

2017-04-01

Although atmospheric 222radon (222Rn) activity concentration measurements are currently performed worldwide, they are being made by many different laboratories and with fundamentally different measurement principles, so compatibility issues can limit their utility for regional-to-global applications. Consequently, we conducted a European-wide 222Rn / 222Rn progeny comparison study in order to evaluate the different measurement systems in use, determine potential systematic biases between them, and estimate correction factors that could be applied to harmonize data for their use as a tracer in atmospheric applications. Two compact portable Heidelberg radon monitors (HRM) were moved around to run for at least 1 month at each of the nine European measurement stations included in this comparison. Linear regressions between parallel data sets were calculated, yielding correction factors relative to the HRM ranging from 0.68 to 1.45. A calibration bias between ANSTO (Australian Nuclear Science and Technology Organisation) two-filter radon monitors and the HRM of ANSTO / HRM = 1.11 ± 0.05 was found. Moreover, for the continental stations using one-filter systems that derive atmospheric 222Rn activity concentrations from measured atmospheric progeny activity concentrations, preliminary 214Po / 222Rn disequilibrium values were also estimated. Mean station-specific disequilibrium values between 0.8 at mountain sites (e.g. Schauinsland) and 0.9 at non-mountain sites for sampling heights around 20 to 30 m above ground level were determined. The respective corrections for calibration biases and disequilibrium derived in this study need to be applied to obtain a compatible European atmospheric 222Rn data set for use in quantitative applications, such as regional model intercomparison and validation or trace gas flux estimates with the radon tracer method.

Andes Hantavirus-Infection of a 3D Human Lung Tissue Model Reveals a Late Peak in Progeny Virus Production Followed by Increased Levels of Proinflammatory Cytokines and VEGF-A

PubMed Central

Sundström, Karin B.; Nguyen Hoang, Anh Thu; Gupta, Shawon; Ahlm, Clas; Svensson, Mattias; Klingström, Jonas

2016-01-01

Andes virus (ANDV) causes hantavirus pulmonary syndrome (HPS), a severe acute disease with a 40% case fatality rate. Humans are infected via inhalation, and the lungs are severely affected during HPS, but little is known regarding the effects of ANDV-infection of the lung. Using a 3-dimensional air-exposed organotypic human lung tissue model, we analyzed progeny virus production and cytokine-responses after ANDV-infection. After a 7–10 day period of low progeny virus production, a sudden peak in progeny virus levels was observed during approximately one week. This peak in ANDV-production coincided in time with activation of innate immune responses, as shown by induction of type I and III interferons and ISG56. After the peak in ANDV production a low, but stable, level of ANDV progeny was observed until 39 days after infection. Compared to uninfected models, ANDV caused long-term elevated levels of eotaxin-1, IL-6, IL-8, IP-10, and VEGF-A that peaked 20–25 days after infection, i.e., after the observed peak in progeny virus production. Notably, eotaxin-1 was only detected in supernatants from infected models. In conclusion, these findings suggest that ANDV replication in lung tissue elicits a late proinflammatory immune response with possible long-term effects on the local lung cytokine milieu. The change from an innate to a proinflammatory response might be important for the transition from initial asymptomatic infection to severe clinical disease, HPS. PMID:26907493

Andes Hantavirus-Infection of a 3D Human Lung Tissue Model Reveals a Late Peak in Progeny Virus Production Followed by Increased Levels of Proinflammatory Cytokines and VEGF-A.

PubMed

Sundström, Karin B; Nguyen Hoang, Anh Thu; Gupta, Shawon; Ahlm, Clas; Svensson, Mattias; Klingström, Jonas

2016-01-01

Andes virus (ANDV) causes hantavirus pulmonary syndrome (HPS), a severe acute disease with a 40% case fatality rate. Humans are infected via inhalation, and the lungs are severely affected during HPS, but little is known regarding the effects of ANDV-infection of the lung. Using a 3-dimensional air-exposed organotypic human lung tissue model, we analyzed progeny virus production and cytokine-responses after ANDV-infection. After a 7-10 day period of low progeny virus production, a sudden peak in progeny virus levels was observed during approximately one week. This peak in ANDV-production coincided in time with activation of innate immune responses, as shown by induction of type I and III interferons and ISG56. After the peak in ANDV production a low, but stable, level of ANDV progeny was observed until 39 days after infection. Compared to uninfected models, ANDV caused long-term elevated levels of eotaxin-1, IL-6, IL-8, IP-10, and VEGF-A that peaked 20-25 days after infection, i.e., after the observed peak in progeny virus production. Notably, eotaxin-1 was only detected in supernatants from infected models. In conclusion, these findings suggest that ANDV replication in lung tissue elicits a late proinflammatory immune response with possible long-term effects on the local lung cytokine milieu. The change from an innate to a proinflammatory response might be important for the transition from initial asymptomatic infection to severe clinical disease, HPS.

Daily variation of radon gas and its short-lived progeny concentration near ground level and estimation of aerosol residence time

NASA Astrophysics Data System (ADS)

M, Mohery; A, M. Abdallah; A, Ali; S, S. Baz

2016-05-01

Atmospheric concentrations of radon (222Rn) gas and its short-lived progenies 218Po, 214Pb, and 214Po were continuously monitored every four hours at the ground level in Jeddah city, Kingdom of Saudi Arabia. The measurements were performed three times every week, starting from November 2014 to October 2015. A method of electrostatic precipitation of positively charged 218Po and 214Po by a positive voltage was applied for determining 222Rn gas concentration. The short-lived 222Rn progeny concentration was determined by using a filter holder connected with the alpha-spectrometric technique. The meteorological parameters (relative air humidity, air temperature, and wind speed) were determined during the measurements of 222Rn and its progeny concentrations. 222Rn gas as well as its short-lived progeny concentration display a daily and seasonal variation with high values in the night and early morning hours as compared to low values at noon and in the afternoon. The observed monthly atmospheric concentrations showed a seasonal trend with the highest values in the autumn/winter season and the lowest values in the spring/summer season. Moreover, and in parallel with alpha-spectrometric measurements, a single filter-holder was used to collect air samples. The deposited activities of 214Pb and the long-lived 222Rn daughter 210Pb on the filter were measured with the gamma spectrometric technique. The measured activity concentrations of 214Pb by both techniques were found to be relatively equal largely. The highest mean seasonally activity concentrations of 210Pb were observed in the autumn/winter season while the lowest mean were observed in the spring/summer season. The mean residence time (MRT) of aerosol particles in the atmospheric air could be estimated from the activity ratios of 210Pb/214Pb. Project supported by the Deanship of Scientific Research (DSR), King Abdulaziz University, Jeddah (Grant No. 291/965/1434).

Assessment of glucose homeostasis in crossbred steer progeny sired by Brahman bulls that experienced prenatal transportation stress

USDA-ARS?s Scientific Manuscript database

The objective of this experiment was to assess glucose homeostasis of crossbred male progeny whose Brahman sires experienced prenatal transportation stress (PS) in utero. Sixteen steers (PNS group) sired by 3 PS bulls gestating dams were transported for 2 h at 60, 80, 100, 120, and 140 ± 5 d of gest...

Variation in pin knot frequency in black walnut lumber cut from a small provenance/progeny test

Treesearch

Peter Y. S. Chen; Robert E. Bodkin; J. W. Van Sambeek

1995-01-01

This small study examined the frequency of knots (> 1 growth ring), pin knots (latent or suppressed buds), and pin knot clusters in 414 black walnut (Juglans nigra L.) lumber from 42 logs. 18 to 21 cm dbh, cut from a 14-year-old provenance/progeny test. Two boards from opposite sides of each log were analyzed for number of knots, pin knots, and...

Comparison of remote consequences in Taraxacum officinale seed progeny collected in radioactively or chemically contaminated areas.

PubMed

Pozolotina, Vera N; Antonova, Elena V; Bezel, Victor S

2012-10-01

We carried out a comparative study of seed progeny taken from the dandelion (Taraxacum officinale s.l.) coenopopulations exposed for a long time to radioactive or chemical contamination originated from the East-Ural radioactive trace zone (EURT) or Nizhniy Tagil metallurgical combine impact zone (NTMC), respectively. Coenopopulations from EURT, NTMC and background areas significantly differ from each other with respect to the qualitative and quantitative composition of allozyme phenes. An analysis of clonal diversity showed the uniqueness of all coenopopulations in terms of their phenogenetics. P-generation seed viability was found to decrease in a similar manner as all types of the industrial stress increased. Studies of F (1)-generation variability in radio- and metal resistance by family analysis showed that seed progeny from EURT impact zone possessed high viability that, however, was accompanied by development of latent injuries resulting in low resistance to additional man-caused impacts. In F (1)-generation originated from NTMC zone, high seed viability was combined with increased resistance to provocative heavy metal and radiation exposure. No significant differences in responses to 'habitual' and 'new' factors, i.e. pre-adaptation effect, were found in samples from the contaminated areas.

Family-site interaction in Pinus radiata: implications for progeny testing strategy and regionalised breeding in New Zealand.

Treesearch

G.R. Johnson; R.D. Brudon

1990-01-01

A progeny test of 170 open-pollinated families from second-generation plus trees of Pinus radiata was established on four sites in New Zealand in 1981. Two test sites were on volcanic purnice soils in the Central North Island region and two were on phosphate-retentive clay soils in the Northland region.Assessments of volume growth, stem straightness, mal-...

Dosimetry of radium-223 and progeny

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

Fisher, D.R.; Sgouros, G.

Radium-223 is a short-lived (11.4 d) alpha emitter with potential applications in radioimmunotherapy of cancer. Radium-223 can be complexed and linked to protein delivery molecules for specific tumor-cell targeting. It decays through a cascade of short-lived alpha- and beta-emitting daughters with emission of about 28 MeV of energy through complete decay. The first three alpha particles are essentially instantaneous. Photons associated with Ra-223 and progeny provide the means for tumor and normal-organ imaging and dosimetry. Two beta particles provide additional therapeutic value. Radium-223 may be produced economically and in sufficient amounts for widescale application. Many aspects of the chemistry ofmore » carrier-free isotope preparation, complexation, and linkage to the antibody have been developed and are being tested. The radiation dosimetry of a Ra-223-labeled antibody shows favorable tumor to normal tissue dose ratios for therapy. The 11.4-d half-life of Ra-223 allows sufficient time for immunoconjugate preparation, administration, and tumor localization by carrier antibodies before significant radiological decay takes place. If 0.01 percent of a 37 MBq (1 mCi) injection deposits in a one gram tumor mass, and if the activity is retained with a typical effective half-time (75 h), the absorbed dose will be 163 mGy MBq{sup {minus}1} (600 rad mCi{sup {minus}1}) administered. 49 refs., 5 figs., 2 tabs.« less

Assessing hybrid sterility in Oryza glaberrima x O. sativa hybrid progenies by PCR marker analysis and crossing with wide compatibility varieties.

PubMed

Heuer, Sigrid; Miézan, Kouamé M

2003-09-01

Interspecific crossing of the African indigenous rice Oryza glaberrima with Oryza sativa cultivars is hindered by crossing barriers causing 100% spikelet sterility in F(1) hybrids. Since hybrids are partially female fertile, fertility can be restored by back crossing (BC) to a recurrent male parent. Distinct genetic models on spikelet sterility have been developed predicting, e.g., the existence of a gamete eliminator and/or a pollen killer. Linkage of sterility to the waxy starch synthase gene and the chromogen gene C, both located on chromosome 6, have been demonstrated. We selected a segregating BC(2)F(3) population of semi-sterile O. glaberrima x O. sativa indica hybrid progenies for analyses with PCR markers located at the respective chromosome-6 region. These analyses revealed that semi-sterile plants were heterozygous for a marker (OSR25) located in the waxy promoter, whereas fertile progenies were homozygous for the O. glaberrima allele. Adjacent markers showed no linkage to spikelet sterility. Semi-sterility of hybrid progenies was maintained at least until the F(4) progeny generation, suggesting the existence of a pollen killer in this plant material. Monitoring of reproductive plant development showed that spikelet sterility was at least partially due to an arrest of pollen development at the microspore stage. In order to address the question whether genes responsible for F(1) sterility in intraspecific hybrids ( O. sativa indica x japonica) also cause spikelet sterility in interspecific hybrids, crossings with wide compatibility varieties (WCV) were performed. WCV accessions possess "neutral" S-loci ( S(n)) improving fertility in intraspecific hybrids. This experiment showed that the tested S(n)-loci had no fertility restoring effect in F(1) interspecific hybrids. Pollen development was completely arrested at the microspore stage and grains were never obtained after selfing. This suggests that distinct or additional S-loci are responsible for sterility

Brood stock segregation for the control of bacterial kidney disease can affect mortality of progeny chinook salmon (Oncorhynchus tshawytscha) in seawater

USGS Publications Warehouse

Elliott, Diane G.; Pascho, Ronald J.; Palmisano, Aldo N.

1995-01-01

Segregation of spring chinook salmon (Oncorhynchus tshawytscha) brood stock based on the measurement of maternal Renibacterium salmoninarum infection levels by the enzyme-linked immunosorbent assay (ELISA) and the fluorescent antibody technique (FAT) was previously shown to affect the prevalence and levels of bacterial kidney disease (BKD) in progeny fish during hatchery rearing. Smolts from that study were subjected to standardized fish health and condition evaluation procedures 2 weeks before the conclusion of hatchery rearing and release of the fish for migration to the Pacific Ocean. The results suggested that the general health of the smolts in the progeny group from parents that had low R. salmoninarum infection levels or tested negative for R. salmoninarum (low-BKD group) was better than that of the smolts in the progeny group from female parents with high R. salmoninarum infection levels (high-BKD group). Testing by the ELISA showed that the overall severity of R. salmoninarum infection also was lower in the smolts from the low-BKD group. Subgroups of smolts from the study were acclimated to tanks of seawater for extended holding. After a 22-day acclimation period and 98 days in full-strength (29 ppt salinity) seawater, total mortality was 12% in the low-BKD group and 44% in the high-BKD group. All of the mortality in the low-BKD group and 85% of the mortality in the high-BKD group occurred after the fish were transferred to full-strength seawater. Testing of kidney tissues from all dead fish by the FAT revealed that 85% of the fish that died in the high-BKD group had high R. salmoninarum numbers, indicating that BKD was the cause of death. In contrast, none of the fish that died in the low-BKD group had detectable numbers of R. salmoninarum. We concluded that brood stock segregation by use of the ELISA and the FAT can affect mortality and the R. salmoninarum status of progeny chinook salmon for as long as 21 months after hatching, even after the fish have

Variability of Virgin Olive Oil Phenolic Compounds in a Segregating Progeny from a Single Cross in Olea europaea L. and Sensory and Nutritional Quality Implications

PubMed Central

Pérez, Ana G.; León, Lorenzo; Pascual, Mar; Romero-Segura, Carmen; Sánchez-Ortiz, Araceli; de la Rosa, Raúl; Sanz, Carlos

2014-01-01

Virgin olive oil phenolic compounds are responsible for its nutritional and sensory quality. The synthesis of phenolic compounds occurs when enzymes and substrates meet as olive fruit is crushed during the industrial process to obtain the oil. The genetic variability of the major phenolic compounds of virgin olive oil was studied in a progeny of the cross of Picual x Arbequina olive cultivars (Olea europaea L.). They belong to four different groups: compounds that included tyrosol or hydroxytyrosol in their molecules, lignans, flavonoids, and phenolic acids. Data of phenolics in the oils showed that the progeny displayed a large degree of variability, widely transgressing the genitor levels. This high variability can be of interest on breeding programs. Thus, multivariate analysis allowed to identify genotypes within the progeny particularly interesting in terms of phenolic composition and deduced organoleptic and nutritional quality. The present study has demonstrated that it is possible to obtain enough degree of variability with a single cross of olive cultivars for compounds related to the nutritional and organoleptic properties of virgin olive oil. PMID:24651694

Variability of virgin olive oil phenolic compounds in a segregating progeny from a single cross in Olea europaea L. and sensory and nutritional quality implications.

PubMed

Pérez, Ana G; León, Lorenzo; Pascual, Mar; Romero-Segura, Carmen; Sánchez-Ortiz, Araceli; de la Rosa, Raúl; Sanz, Carlos

2014-01-01

Virgin olive oil phenolic compounds are responsible for its nutritional and sensory quality. The synthesis of phenolic compounds occurs when enzymes and substrates meet as olive fruit is crushed during the industrial process to obtain the oil. The genetic variability of the major phenolic compounds of virgin olive oil was studied in a progeny of the cross of Picual x Arbequina olive cultivars (Olea europaea L.). They belong to four different groups: compounds that included tyrosol or hydroxytyrosol in their molecules, lignans, flavonoids, and phenolic acids. Data of phenolics in the oils showed that the progeny displayed a large degree of variability, widely transgressing the genitor levels. This high variability can be of interest on breeding programs. Thus, multivariate analysis allowed to identify genotypes within the progeny particularly interesting in terms of phenolic composition and deduced organoleptic and nutritional quality. The present study has demonstrated that it is possible to obtain enough degree of variability with a single cross of olive cultivars for compounds related to the nutritional and organoleptic properties of virgin olive oil.

Tobacco Mosaic Virus Infection Results in an Increase in Recombination Frequency and Resistance to Viral, Bacterial, and Fungal Pathogens in the Progeny of Infected Tobacco Plants1[C][W][OA

PubMed Central

Kathiria, Palak; Sidler, Corinne; Golubov, Andrey; Kalischuk, Melanie; Kawchuk, Lawrence M.; Kovalchuk, Igor

2010-01-01

Our previous experiments showed that infection of tobacco (Nicotiana tabacum) plants with Tobacco mosaic virus (TMV) leads to an increase in homologous recombination frequency (HRF). The progeny of infected plants also had an increased rate of rearrangements in resistance gene-like loci. Here, we report that tobacco plants infected with TMV exhibited an increase in HRF in two consecutive generations. Analysis of global genome methylation showed the hypermethylated genome in both generations of plants, whereas analysis of methylation via 5-methyl cytosine antibodies demonstrated both hypomethylation and hypermethylation. Analysis of the response of the progeny of infected plants to TMV, Pseudomonas syringae, or Phytophthora nicotianae revealed a significant delay in symptom development. Infection of these plants with TMV or P. syringae showed higher levels of induction of PATHOGENESIS-RELATED GENE1 gene expression and higher levels of callose deposition. Our experiments suggest that viral infection triggers specific changes in progeny that promote higher levels of HRF at the transgene and higher resistance to stress as compared with the progeny of unstressed plants. However, data reported in these studies do not establish evidence of a link between recombination frequency and stress resistance. PMID:20498336

Differential segregation of nodaviral coat protein and RNA into progeny virions during mixed infection with FHV and NoV

PubMed Central

Gopal, Radhika; Venter, P. Arno; Schneemann, Anette

2014-01-01

Nodaviruses are icosahedral viruses with a bipartite, positive-sense RNA genome. The two RNAs are packaged into a single virion by a poorly understood mechanism. We chose two distantly related nodaviruses, Flock House virus and Nodamura virus, to explore formation of viral reassortants as a means to further understand genome recognition and encapsidation. In mixed infections, the viruses were incompatible at the level of RNA replication and their coat proteins segregated into separate populations of progeny particles. RNA packaging, on the other hand, was indiscriminate as all four viral RNAs were detectable in each progeny population. Consistent with the trans-encapsidation phenotype, fluorescence in situ hybridization of viral RNA revealed that the genomes of the two viruses co-localized throughout the cytoplasm. Our results imply that nodaviral RNAs lack rigorously defined packaging signals and that coencapsidation of the viral RNAs does not require a pair of cognate RNA1 and RNA2. PMID:24725955

Stability analysis of oil yield in oil palm (Elaeis guineensis) progenies in different environments.

PubMed

Rafii, M Y; Jalani, B S; Rajanaidu, N; Kushairi, A; Puteh, A; Latif, M A

2012-10-04

We evaluated 38 dura x pisifera (DP) oil palm progenies in four locations in Malaysia for genotype by environment interaction and genotypic stability studies. The DP progenies derived from crosses between pisifera palms of AVROS, Serdang S27B, Serdang 29/36, and Lever Cameroon were chosen to be the males' parent and Deli dura palms designated as females' parent. All the locations differed in terms of soil physical and chemical properties, and the soil types ranged from coastal clay to inland soils. The genotype by environment interaction and stability of the individual genotypes were analyzed for oil yield trait using several stability techniques. A genotype by environment interaction was detected for oil yield and it had a larger variance component than genotypic variance (σ(2)(gl)/σ(2)(g) = 139.7%). Genotype by environment interaction of oil yield was largely explained by a non-linear relationship between genotypic and environmental values. Overall assessment of individual genotypic stability showed that seven genotypes were highly stable and had consistent performance over the environments for the oil yield trait [total individual genotype stability scored more than 10 and mean oil yielded above the average of the environment (genotype means are more than 34.37 kg·palm(-1)·year(-1))]. These genotypes will be useful for oil palm breeding and tissue culture programs for developing high oil yielding planting materials with stable performance.

Optimized testing schemes using nucleus progeny, adult MOET siblings, or juvenile MOET pedigrees in dairy cattle closed populations.

PubMed

Bondoc, O L; Smith, C

1993-01-12

Selection response rates are predicted for nucleus progeny testing, adult multiple ovulation and embryo transfer (MOET) sib testing, and juvenile MOET pedigree testing in closed populations. Deterministic models are adapted to adjust predicted genetic gains for the effects of population size and structure, selection disequilibrium, sampling losses, and inbreeding depression. The improvement schemes were optimized for different numbers of sires used and first lactation females recorded per year. The number of nucleus daughters tested per sire, and of females per MOET full sibship, that maximize the predicted response to selection per year, were determined. Annual genetic gains and inbreeding rates were interpolated to the same planning horizon (20 years) to compare the optimized schemes for a wide range of situations. The predicted maximum genetic gain per year is higher for adult MOET than for juvenile MOET (due to the proportional extra time to collect the embryos needed) and for nucleus progeny testing. Average annual inbreeding rates are much higher for MOET schemes than for nucleus progeny testing. The advantages of adult and juvenile over nucleus progeny testing are little affected by planning horizon, but are higher with more females recorded per year, higher heritability, and higher reproductive and MOET success rates. Comparison of the schemes at the same level of inbreeding is fairer for fixed testing resources. At the same inbreeding level, the genetic advantage of adult MOET was generally maintained, but juvenile MOET then lost its advantage over progeny testing in these closed populations. ZUSAMMENFASSUNG: Optimierte Prüfpläne für Nukleusnachkommen, adulte MOET Geschwister oder juvenile MOET Pedigrees in geschlossenen Milchviehpopulationen Selektionserfolge werden für Nukleusnachkommenprüfung, adulte multiple Ovulation (MOET) und Embryotransfer, Geschwisterprüfung und juvenile MOET Pedigreeprüfung geschlossener Populationen gesch

Assessment of volatile compound profiles and the deduced sensory significance of virgin olive oils from the progeny of Picual×Arbequina cultivars.

PubMed

Pérez, Ana G; de la Rosa, Raúl; Pascual, Mar; Sánchez-Ortiz, Araceli; Romero-Segura, Carmen; León, Lorenzo; Sanz, Carlos

2016-01-08

Volatile compounds are responsible for most of the sensory qualities of virgin olive oil and they are synthesized when enzymes and substrates come together as olive fruit is crushed during the industrial process to obtain the oil. Here we have studied the variability among the major volatile compounds in virgin olive oil prepared from the progeny of a cross of Picual and Arbequina olive cultivars (Olea europaea L.). The volatile compounds were isolated by SPME, and analyzed by HRGC-MS and HRGC-FID. Most of the volatile compounds found in the progeny's oil are produced by the enzymes in the so-called lipoxygenase pathway, and they may be clustered into different groups according to their chain length and polyunsaturated fatty acid origin (linoleic and linolenic acids). In addition, a group of compounds derived from amino acid metabolism and two terpenes also contributed significantly to the volatile fraction, some of which had significant odor values in most of the genotypes evaluated. The volatile compound content of the progeny was very varied, widely transgressing the progenitor levels, suggesting that in breeding programs it might be more effective to consider a larger number of individuals within the same cross than using different crosses with fewer individuals. Multivariate analysis allowed genotypes with particularly interesting volatile compositions to be identified and their flavor quality deduced. Copyright © 2015 Elsevier B.V. All rights reserved.

Eco-geographically divergent diploids, Caucasian clover (Trifolium ambiguum) and western clover (T. occidentale), retain most requirements for hybridization

PubMed Central

Williams, Warren M.; Verry, Isabelle M.; Ansari, Helal A.; Hussain, S. Wajid; Ullah, Ihsan; Williamson, Michelle L.; Ellison, Nicholas W.

2011-01-01

Background and Aims DNA sequence similarities and hybridization patterns in Trifolium (clovers) section Trifoliastrum suggest that rapid radiation from a common ancestral source led to this complex of diverse species distributed across Europe, western Asia and North Africa. Two of the most geographically and ecologically divergent of these species are the rhizomatous T. ambiguum from high altitudes in eastern Europe and western Asia and the stoloniferous T. occidentale from sea level in western Europe. Attempts were made to hybridize these species to ascertain whether, despite this separation, gene flow could be achieved, indicating the retention of the genetic factors necessary for hybridization. Methods Three F1 hybrids formed after embryo rescue were described, characterized by conventional and molecular cytogenetics, subjected to fertility tests and progeny generations were developed. Results and Conclusions Partially fertile hybrids between Trifolium ambiguum and T. occidentale were obtained for the first time. The F1 hybrids produced seeds after open-pollination, and also produced triploid progeny in backcrosses to T. occidentale from the functioning of unreduced gametes in the hybrids. These plants were fertile and produced progeny with T. occidentale and with T. repens. Meiotic chromosome pairing in the F1 showed six to eight bivalents per pollen mother cell, indicating pairing between the parental genomes. A chromosome-doubled form of one hybrid, produced using colchicine, showed some multivalents, indicative of interspecific chromosome pairing. The hybrid plants were robust and combined phenotypic characteristics of both species, having stolons, thick roots and a few rhizomes. Results show that despite separation by the entire breadth of Europe, the speciation process is incomplete, and these taxa have partially retained most of the genetic compatibilities needed for hybridization (possibly except for endosperm development, which was not tested). The

Dominant Inheritance of Field-Evolved Resistance to Fipronil in Plutella xylostella (Lepidoptera: Plutellidae).

PubMed

Wang, Xingliang; Wu, Shuwen; Gao, Weiyue; Wu, Yidong

2016-02-01

A field-collected strain (HF) of Plutella xylostella (L.) showed 420-fold resistance to fipronil compared with a susceptible laboratory strain (Roth). The HF-R strain, derived from the HF strain by 25 generations of successive selection with fipronil in the laboratory, developed 2,200-fold resistance to fipronil relative to the Roth strain. The F(1) progeny of the reciprocal crosses between HF-R and Roth showed 640-fold (R♀ × S♂) and 1,380-fold (R♂ × S♀) resistance to fipronil, indicating resistance is inherited as an incompletely dominant trait. Analysis of progeny from a backcross (F1♂ × S♀) suggests that resistance is controlled by one major locus. The LC(50) of the R♂ × S♀ cross F(1) progeny is slightly but significantly higher than that of the R♀ × S♂ cross F(1) progeny, suggesting a minor resistance gene on the Z chromosome. Sequence analysis of PxGABARα1 (an Rdl-homologous GABA receptor gene of P. xylostella) from the HF-R strain identified two mutations A282S and A282G (corresponding to the A302S mutation of the Drosophila melanogaster Rdl gene), which have been previously implicated in fipronil resistance in several insect species including P. xylostella. PxGABARα1 was previously mapped to the Z chromosome of P. xylostella. In conclusion, fipronil resistance in the HF-R strain of P. xylostella was incompletely dominant, and controlled by a major autosomal locus and a sex-linked minor gene (PxGABARα1) on the Z chromosome. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

A Novel Quantitative Trait Locus on Mouse Chromosome 18, “era1,” Modifies the Entrainment of Circadian Rhythms

PubMed Central

Wisor, Jonathan P.; Striz, Martin; DeVoss, Jason; Murphy, Greer M.; Edgar, Dale M.; O'Hara, Bruce F.

2007-01-01

Study Objectives: The mammalian circadian clock in the suprachiasmatic nuclei (SCN) of the hypothalamus conveys 24-h rhythmicity to sleep-wake cycles, locomotor activity, and other behavioral and physiological processes. The timing of rhythms relative to the light/dark (LD12:12) cycle is influenced in part by the endogenous circadian period and the time of day specific sensitivity of the clock to light. We now describe a novel circadian rhythm phenotype, and a locus influencing that phenotype, in a segregating population of mice. Methods: By crossbreeding 2 genetically distinct nocturnal strains of mice (Cast/Ei and C57BL/6J) and backcrossing the resulting progeny to Cast/Ei, we have produced a novel circadian phenotype, called early runner mice. Results: Early runner mice entrain to a light/dark cycle at an advanced phase, up to 9 hours before dark onset. This phenotype is not significantly correlated with circadian period in constant darkness and is not associated with disruption of molecular circadian rhythms in the SCN, as assessed by analysis of period gene expression. We have identified a genomic region that regulates this phenotype—a major quantitative trait locus on chromosome 18 (near D18Mit184) that we have named era1 for Early Runner Activity locus one. Phase delays caused by light exposure early in the subjective night were of smaller magnitude in backcross offspring that were homozygous Cast/Ei at D18Mit184 than in those that were heterozygous at this locus. Conclusion: Genetic variability in the circadian response to light may, in part, explain the variance in phase angle of entrainment in this segregating mouse population. Citation: Wisor JP; Striz M; DeVoss J; Murphy GM; Edgar DM; O'Hara BF. A novel quantitative trait locus on mouse chromosome 18, “era1,” modifies the entrainment of circadian rhythms. SLEEP 2007;30(10):1255-1263. PMID:17969459

Feeding corn distillers grains as an energy source to gestating and lactating beef heifers: Impact of excess protein on feedlot performance, glucose tolerance, carcass characteristics and Longissimus muscle fatty acid profile of steer progeny.

PubMed

Gunn, Patrick J; Bridges, Glen A; Lemenager, Ronald P; Schoonmaker, Jon P

2017-09-01

This study was conducted to determine the impact of dried distiller's grain with solubles (DDGS) from 192 days of gestation through 118 days of lactation on feedlot performance, carcass characteristics, Longissimus muscle (LM) fatty acids and glucose tolerance of male progeny (n = 36). Angus-Simmental heifer dams were fed diets that contained either DDGS (DG) or not (CON) formulated to provide similar daily net energy for gain but differing crude protein. In the feedlot, male progeny were fed a diet devoid of DDGS. An intravenous glucose tolerance test (IVGTT) was performed on a subset of 20 steers prior to harvest. Steers were harvested at a common 12th rib fat depth. Data were analyzed with the GLIMMIX and MIXED procedures of SAS. Performance (P ≥ 0.11) and glucose and insulin concentrations during IVGTT (P ≥ 0.24) did not differ between treatments. Dressing percentage tended to be greater (P = 0.09) in DG than CON progeny, but all other carcass characteristics did not differ (P ≥ 0.18). Progeny from DG dams had greater LM 16:2, 18:0, and 20:1 n-9 concentrations than progeny from CON dams (P ≤ 0.02). In conclusion, DDGS are a viable option for gestating and lactating beef cows. © 2017 Japanese Society of Animal Science.

Divergent host preferences of above- and below-ground Culex pipiens mosquitoes and their hybrid offspring.

PubMed

Fritz, M L; Walker, E D; Miller, J R; Severson, D W; Dworkin, I

2015-06-01

Culex pipiens form pipiens and Cx. pipiens form molestus (Diptera: Culicidae) belong to a cosmopolitan taxonomic group known as the Pipiens Assemblage. Hybridization between these forms is thought to contribute to human transmission of West Nile virus (WNV) in North America. Complementary choice and no-choice landing assays were developed to examine host acceptance by North American Cx. pipiens in the laboratory. Populations collected from above- and below-ground sites in suburban Chicago were identified as forms pipiens and molestus using a polymerase chain reaction-based assay. Avian and human host acceptance was then quantified for the two populations, as well as for their hybrid and backcross offspring. No-choice tests were used to demonstrate that both the pipiens and molestus forms were capable of feeding on human and avian hosts. Choice tests were used to demonstrate that form pipiens females were strongly avian-seeking; an individual's probability of accepting the chick host was 85%. Form molestus females were more likely to accept the human host (87%). Rates of host acceptance by F1 and backcross progeny were intermediate to those of their parents. The results suggest that host preferences in Cx. pipiens are genetically determined, and that ongoing hybridization between above- and below-ground populations is an important contributor to epizootic transmission of WNV in North America. © 2015 The Royal Entomological Society.

Impact of transgene genome location on gene migration from herbicide-resistant wheat (Triticum aestivum L.) to jointed goatgrass (Aegilops cylindrica Host).

PubMed

Rehman, Maqsood; Hansen, Jennifer L; Mallory-Smith, Carol A; Zemetra, Robert S

2017-08-01

Wheat (Triticum aestivum) (ABD) and jointed goatgrass (Aegilops cylindrica) (CD) can cross and produce hybrids that can backcross to either parent. Such backcrosses can result in progeny with chromosomes and/or chromosome segments retained from wheat. Thus, a herbicide resistance gene could migrate from wheat to jointed goatgrass. In theory, the risk of gene migration from herbicide-resistant wheat to jointed goatgrass is more likely if the gene is located on the D genome and less likely if the gene is located on the A or B genome of wheat. BC 1 populations (jointed goatgrass as a recurrent parent) were analyzed for chromosome numbers and transgene transmission rates under sprayed and non-sprayed conditions. Transgene retention in the non-sprayed BC 1 generation for the A, B and D genomes was 84, 60 and 64% respectively. In the sprayed populations, the retention was 81, 59 and 74% respectively. The gene transmission rates were higher than the expected 50% or less under sprayed and non-sprayed conditions, possibly owing to meiotic chromosome restitution and/or chromosome non-disjunction. Such high transmission rates in the BC 1 generation negates the benefits of gene placement for reducing the potential of gene migration from wheat to jointed goatgrass. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Observations and modelling of thoron and its progeny in the soil-atmosphere-plant system.

PubMed

Baldacci, A E; Gattavecchia, E; Kirchner, G

2010-11-01

Samples of pasture vegetation, mainly Trifolium pratensis, were collected at the Botanic Garden of the University of Bologna during the period 1998-2000 and measured by gamma-spectrometry for determining thoron progeny. Concentrations of (212)Pb were between 1.5 and 20 Bq m(-2), with individual peaks up to 70 Bq m(-2). Soil samples were collected at the same location and physically characterised. Their chemical composition (particularly Th and U) was determined by X-ray fluorescence spectroscopy. Lead-212 on plants mainly originates from dry and wet deposition of this isotope generated in the lower atmosphere by the decay of its short-lived precursor (220)Rn, which is produced in the upper soil layers as a member of the natural thorium decay chain and exhales into the atmosphere. Concentrations of (220)Rn in the atmosphere depend on (1) the amount of Th present in soil, (2) the radon fraction which escapes from the soil minerals into the soil pore space, (3) its transport into the atmosphere, and (4) its redistribution within the atmosphere. The mobility of radon in soil pore space can vary by orders of magnitude depending on the soil water content, thus being the main factor for varying concentrations of (220)Rn and (212)Pb in the atmosphere. We present a simple model to predict concentrations of thoron in air and its progeny deposited from the atmosphere, which takes into account varying soil moisture contents calculated by the OPUS code. Results of this model show close agreement with our observations.

Effect of indica pedigree on eating and cooking quality in rice backcross inbred lines of indica and japonica crosses

PubMed Central

Fan, Mingyu; Wang, Xiaojing; Sun, Jian; Zhang, Qun; Xu, Zhengjin; Xu, Quan

2017-01-01

Amylopectin is one of the major determinants of rice (Oryza sativa L.) grain quality, and a large difference in amylopectin is found between two subspecies: japonica and indica. However, the relationship among rice grain quality, indica/japonica genetic background, and amylopectin has not been clearly established. In this study, a series of backcross inbred lines derived from the cross between japonica (cv. Sasanishiki) and indica (cv. Habataki) were used to survey eating and cooking quality (ECQ), rapid visco analyzer (RVA) profiles, and the chain length distribution of amylopectin. The frequency of indica pedigree (Fi) was calculated to analyze the effects of Fi on grain quality and amylopectin. The results showed that the Sasanishiki cultivar was markedly enriched in chain length with DP6-15 and DP34-45 compared to the Habataki. DP34-45 strongly correlated to RVA characteristics, cooking quality, and prolamin content. The Fi also has significant correlations to RVA characteristics and ECQ, but only significantly negative correlation to DP34-45. Seven quantitative trait loci (QTLs) corresponding to amylopectin were mapped, of which three were in agreement with previous findings. The results of this study provide valuable information for amylopectin characteristics in the offspring derived from the subspecies cross, and the novel QTLs may provide new insights to the identification of minor starch synthesis-related genes. PMID:29398938

Lgr6+ stem cells and their progeny in mouse epidermis under regimens of exogenous skin carcinogenesis, and their absence in ensuing skin tumors.

PubMed

van de Glind, Gerline C; Rebel, Heggert G; Out-Luiting, Jacoba J; Zoutman, Wim; Tensen, Cornelis P; de Gruijl, Frank R

2016-12-27

Lgr6+ cells have been identified as a novel class of proliferating (Ki67+) stem cells in mouse epidermis. We investigated their response to UV exposure in Lgr6-EGFP-Ires-CreERT2/R26R-LacZ haired and hairless mice and whether they become initiating cells of UV- or chemically induced skin tumors. UV overexposure erased Lgr6+ cells (EGFP+) from the interfollicular epidermis (IFE), but - as after wounding - they apparently repopulated the IFE from the hair follicles. Under sub-sunburn chronic UV exposure, Lgr6+ cells and their progeny (LacZ+ after pulse of tamoxifen) diminished strongly in the IFE. Although the inter-tumoral IFE clearly showed Lgr6 progeny, none of the UV- or chemically induced tumors (n = 22 and 41, respectively) appeared to be clonal expansions of Lgr6+ stem cells; i.e. no Lgr6+ cells or progeny in the proliferating tumor bulk. In checking for promoter methylation we found it to occur stochastically for the EGFP-Cre cassette. Lgr6 mRNA measured by qPCR was found to be diminished in skin tumors (also in UV tumors from wt type mice). The ratio of Lgr6/Ki67 was significantly reduced, pointing at a loss of Lgr6+ cells from the proliferative pool. Our data show that Lgr6+ cells are not major tumor-initiating cells in skin carcinogenesis.

Lgr6+ stem cells and their progeny in mouse epidermis under regimens of exogenous skin carcinogenesis, and their absence in ensuing skin tumors

PubMed Central

van de Glind, Gerline C.; Rebel, Heggert G.; Out-Luiting, Jacoba J.; Zoutman, Wim; Tensen, Cornelis P.; de Gruijl, Frank R.

2016-01-01

Lgr6+ cells have been identified as a novel class of proliferating (Ki67+) stem cells in mouse epidermis. We investigated their response to UV exposure in Lgr6-EGFP-Ires-CreERT2/R26R-LacZ haired and hairless mice and whether they become initiating cells of UV- or chemically induced skin tumors. UV overexposure erased Lgr6+ cells (EGFP+) from the interfollicular epidermis (IFE), but - as after wounding - they apparently repopulated the IFE from the hair follicles. Under sub-sunburn chronic UV exposure, Lgr6+ cells and their progeny (LacZ+ after pulse of tamoxifen) diminished strongly in the IFE. Although the inter-tumoral IFE clearly showed Lgr6 progeny, none of the UV- or chemically induced tumors (n = 22 and 41, respectively) appeared to be clonal expansions of Lgr6+ stem cells; i.e. no Lgr6+ cells or progeny in the proliferating tumor bulk. In checking for promoter methylation we found it to occur stochastically for the EGFP-Cre cassette. Lgr6 mRNA measured by qPCR was found to be diminished in skin tumors (also in UV tumors from wt type mice). The ratio of Lgr6/Ki67 was significantly reduced, pointing at a loss of Lgr6+ cells from the proliferative pool. Our data show that Lgr6+ cells are not major tumor-initiating cells in skin carcinogenesis. PMID:27880932

Field experience on indoor radon, thoron and their progenies with solid-state detectors in a survey of Kosovo and Metohija (Balkan region).

PubMed

Gulan, L; Milic, G; Bossew, P; Omori, Y; Ishikawa, T; Mishra, R; Mayya, Y S; Stojanovska, Z; Nikezic, D; Vuckovic, B; Zunic, Z S

2012-11-01

Since 1996/97, indoor radon has been measured in scattered locations around Kosovo. In the most recent campaign, apart from radon, thoron and Rn and Tn progenies have also been measured. The current survey involves 48 houses, in which different detectors have been deployed side-by-side in one room, in order to measure indoor radon and thoron gas with RADUET devices based on CR-39 detectors (analysed by Japanese collaborators) and with direct thoron and radon progeny sensor (DTPS and DRPS) devices based on LR-115 detectors (analysed by collaborators from India). Estimated arithmetic mean values of concentrations in 48 houses are 122 Bq m(-3) for radon and 136 Bq m(-3) for thoron. Those for equilibrium equivalent radon concentration and equilibrium equivalent thoron concentration based on measurements in 48 houses are 40 and 2.1 Bq m(-3), respectively. The arithmetic mean value of the equilibrium factor is estimated to be 0.50 ± 0.23 for radon and 0.037 ± 0.041 for thoron. The preliminary results of these measurements are reported, particularly regarding DTPS and DRPS being set up in real field conditions for the first time in the Balkan region. The results are to be understood under the caveat of open questions related to measurement protocols which yield reproducible and representative results, and to quality assurance of Tn and Rn/Tn progeny measurements in general, some of which are discussed.

Achievements and prospects of genomics-assisted breeding in three legume crops of the semi-arid tropics.

PubMed

Varshney, Rajeev K; Mohan, S Murali; Gaur, Pooran M; Gangarao, N V P R; Pandey, Manish K; Bohra, Abhishek; Sawargaonkar, Shrikant L; Chitikineni, Annapurna; Kimurto, Paul K; Janila, Pasupuleti; Saxena, K B; Fikre, Asnake; Sharma, Mamta; Rathore, Abhishek; Pratap, Aditya; Tripathi, Shailesh; Datta, Subhojit; Chaturvedi, S K; Mallikarjuna, Nalini; Anuradha, G; Babbar, Anita; Choudhary, Arbind K; Mhase, M B; Bharadwaj, Ch; Mannur, D M; Harer, P N; Guo, Baozhu; Liang, Xuanqiang; Nadarajan, N; Gowda, C L L

2013-12-01

Advances in next-generation sequencing and genotyping technologies have enabled generation of large-scale genomic resources such as molecular markers, transcript reads and BAC-end sequences (BESs) in chickpea, pigeonpea and groundnut, three major legume crops of the semi-arid tropics. Comprehensive transcriptome assemblies and genome sequences have either been developed or underway in these crops. Based on these resources, dense genetic maps, QTL maps as well as physical maps for these legume species have also been developed. As a result, these crops have graduated from 'orphan' or 'less-studied' crops to 'genomic resources rich' crops. This article summarizes the above-mentioned advances in genomics and genomics-assisted breeding applications in the form of marker-assisted selection (MAS) for hybrid purity assessment in pigeonpea; marker-assisted backcrossing (MABC) for introgressing QTL region for drought-tolerance related traits, Fusarium wilt (FW) resistance and Ascochyta blight (AB) resistance in chickpea; late leaf spot (LLS), leaf rust and nematode resistance in groundnut. We critically present the case of use of other modern breeding approaches like marker-assisted recurrent selection (MARS) and genomic selection (GS) to utilize the full potential of genomics-assisted breeding for developing superior cultivars with enhanced tolerance to various environmental stresses. In addition, this article recommends the use of advanced-backcross (AB-backcross) breeding and development of specialized populations such as multi-parents advanced generation intercross (MAGIC) for creating new variations that will help in developing superior lines with broadened genetic base. In summary, we propose the use of integrated genomics and breeding approach in these legume crops to enhance crop productivity in marginal environments ensuring food security in developing countries. Copyright © 2012 Elsevier Inc. All rights reserved.

Non-linear relationship of cell hit and transformation probabilities in a low dose of inhaled radon progenies.

PubMed

Balásházy, Imre; Farkas, Arpád; Madas, Balázs Gergely; Hofmann, Werner

2009-06-01

Cellular hit probabilities of alpha particles emitted by inhaled radon progenies in sensitive bronchial epithelial cell nuclei were simulated at low exposure levels to obtain useful data for the rejection or support of the linear-non-threshold (LNT) hypothesis. In this study, local distributions of deposited inhaled radon progenies in airway bifurcation models were computed at exposure conditions characteristic of homes and uranium mines. Then, maximum local deposition enhancement factors at bronchial airway bifurcations, expressed as the ratio of local to average deposition densities, were determined to characterise the inhomogeneity of deposition and to elucidate their effect on resulting hit probabilities. The results obtained suggest that in the vicinity of the carinal regions of the central airways the probability of multiple hits can be quite high, even at low average doses. Assuming a uniform distribution of activity there are practically no multiple hits and the hit probability as a function of dose exhibits a linear shape in the low dose range. The results are quite the opposite in the case of hot spots revealed by realistic deposition calculations, where practically all cells receive multiple hits and the hit probability as a function of dose is non-linear in the average dose range of 10-100 mGy.

Quantitative trait loci for live animal and carcass composition traits in Jersey and Limousin back-cross cattle finished on pasture or feedlot.

PubMed

Morris, C A; Pitchford, W S; Cullen, N G; Esmailizadeh, A K; Hickey, S M; Hyndman, D; Dodds, K G; Afolayan, R A; Crawford, A M; Bottema, C D K

2009-10-01

A quantitative trait locus (QTL) study was carried out in two countries, recording live animal and carcass composition traits. Back-cross calves (385 heifers and 398 steers) were generated, with Jersey and Limousin breed backgrounds. The New Zealand cattle were reared on pasture to carcass weights averaging 229 kg, whilst the Australian cattle were reared on grass and finished on grain (for at least 180 days) to carcass weights averaging 335 kg. From 11 live animal traits and 31 carcass composition traits respectively, 5 and 22 QTL were detected in combined-sire analyses, which were significant (P < 0.05) on a genome-wise basis. Fourteen significant traits for carcass composition QTL were on chromosome 2 and these were traits associated with muscling and fatness. This chromosome carried a variant myostatin allele (F94L), segregating from the Limousin ancestry. Despite very different cattle management systems between the two countries, the two populations had a large number of QTL in common. Of the 18 traits which were common to both countries, and which had significant QTL at the genome-wise level, eight were significant in both countries.

Exploring the power of rice (O. sativa x O. rufipogon) chromosome segment substitution line libraries

USDA-ARS?s Scientific Manuscript database

Transgressive variation was reported as an increase in grain yield for several rice (Oryza sativa x O. rufipogon) advanced backcross mapping populations. The objective of this study was to develop chromosome segment substitution line (CSSL) libraries to further dissect the reported transgressive var...

RADON AND PROGENY SOURCED DOSE ASSESSMENT OF SPA EMPLOYEES IN BALNEOLOGICAL SITES.

PubMed

Uzun, Sefa Kemal; Demiröz, Işık

2016-09-01

This study was conducted in the scope of IAEA project with the name 'Establishing a Systematic Radioactivity Survey and Total Effective Dose Assessment in Natural Balneological Sites' (TUR/9/018), at the Health Physics department of Sarayköy Nuclear Research and Training Center (SANAEM). The aim of this study is estimation of radon and progeny sourced effective dose for the people who are working at the spa facilities by measuring radon activity concentration (RAC) at the ambient air of indoor spa pools and dressing rooms. As it is known, the source of the radon gas is the radium content of the earth crust. Therefore, thermal waters coming from ground may contain dissolved radon and the radon can diffuse water to air. So the ambient air of spa pools can contain serious RAC that depends on a lot of parameters. In this regard, RAC measurements were executed at the 70 spa facilities in Turkey. The measurements were done with both active and passive methods at ambient air of spa pools and dressing rooms. Thus, active measurements were carried out by using the Alphaguard(®) with diffusion mode during half an hour, and passive measurements were carried out by using the humidity resistive CR-39 radon detectors during 2 months. Results show that RAC values at ambient air of spa pools varies between 13 Bq m(-3) and 10 kBq m(-3) Because long-term measurements are more reliable, if it is available, for dose calculations passive radon measurements (with CR-39 detectors) at ambient air of spa pools and dressing rooms were used, otherwise active measurement results were used. With the measurement by the conversion coefficients of ICRP 65 and occupational data of the employees has got from questionary forms, effective dose values were calculated. According to the calculations, spa employees are exposed to annual average dose between 0.05 and 29 mSv because of radon and progeny. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions

Influence of abnormally high leptin levels during pregnancy on metabolic phenotypes in progeny mice.

PubMed

Makarova, Elena N; Chepeleva, Elena V; Panchenko, Polina E; Bazhan, Nadezhda M

2013-12-01

Maternal obesity increases the risk of obesity in offspring, and obesity is accompanied by an increase in blood leptin levels. The "yellow" mutation at the mouse agouti locus (A(y)) increases blood leptin levels in C57BL preobese pregnant mice without affecting other metabolic characteristics. We investigated the influence of the A(y) mutation or leptin injection at the end of pregnancy in C57BL mice on metabolic phenotypes and the susceptibility to diet-induced obesity (DIO) in offspring. In both C57BL-A(y) and leptin-treated mice, the maternal effect was more pronounced in male offspring. Compared with males born to control mothers, males born to A(y) mothers displayed equal food intake (FI) but decreased body weight (BW) gain after weaning, equal glucose tolerance, and enhanced FI-to-BW ratios on the standard diet but the same FI and BW on the high-fat diet. Males born to A(y) mothers were less responsive to the anorectic effect of exogenous leptin and less resistant to fasting (were not hyperphagic and gained less weight during refeeding after food deprivation) compared with males born to control mothers. However, all progeny displayed equal hypothalamic expression of Agouti gene-related protein (AgRP), neuropeptide Y (NPY), and proopiomelanocortin (POMC) and equal plasma leptin and glucose levels after food deprivation. Leptin injections in C57BL mice on day 17 of pregnancy decreased BW in both male and female offspring but inhibited FI and DIO only in male offspring. Our results show that hyperleptinemia during pregnancy has sex-specific long-term effects on energy balance regulation in progeny and does not predispose offspring to developing obesity.

Dietary supplementation of l-arginine and chromium picolinate in sows during gestation affects the muscle fibre characteristics but not the performance of their progeny.

PubMed

Shi, Zhan; Song, Wentao; Sun, Yuecheng; Wang, Liansheng; Shi, Baoming; Shan, Anshan; Bi, Zhongpeng

2018-01-01

The present study investigated the effects of dietary supplementation of l-arginine and chromium picolinate (CrP) in sows during gestation on muscle fibre characteristics, performance and carcass characteristics of their progeny. Sixty healthy sows were randomly divided into four groups as a 2 × 2 factorial experiment design: one group received the control diet, another received the control diet + 10 g kg -1 l-arginine, the third group received the control diet + 400 ppb CrP, and the fourth group received the control diet + 10 g kg -1 l-arginine and 400 ppb CrP. The results showed that sows fed the diet supplemented with CrP produced progeny with higher muscle fibre numbers at birth, weaning and slaughter compared to sows fed the control diet. For mean fibre areas, the same result was found at weaning. For progeny of sows fed diets supplemented with l-arginine, only higher muscle fibre numbers at slaughter was observed. Almost no differences were observed regarding average daily gains, average daily feed intake, gain-to-feed ratios, carcass and meat traits. The results of the present study indicate that dietary supplementation of l-arginine and particularly CrP in sows during gestation alters muscle fibre numbers in their offspring, although not their performance or carcass characteristics. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Behaviours and influence factors of radon progeny in three typical dwellings.

PubMed

Li, Hongzhao; Zhang, Lei; Guo, Qiuju

2011-03-01

To investigate the behaviours and influence factors of radon progeny in rural dwellings in China, site measurements of radon equilibrium factor, unattached fraction and some important indoor environmental factors, such as aerosol concentration, aerosol size distribution and ventilation rate, were carried out in three typical types of dwellings, and a theoretical study was also performed synchronously. Good consistency between the results of site measurements and the theoretical calculation on equilibrium factor F and unattached fraction f(p) was achieved. Lower equilibrium factor and higher unattached fraction in mud or cave houses were found compared to those in brick houses, and it was suggested by the theoretical study that the smaller aerosol size distribution in mud or cave houses might be the main reason for what was observed. The dose conversion factor in the mud houses and the cave houses may be higher than that in brick houses.

Identification of QTLs for rice brown spot resistance in backcross inbred lines derived from a cross between Koshihikari and CH45.

PubMed

Matsumoto, Kengo; Ota, Yuya; Seta, Satomi; Nakayama, Yukinori; Ohno, Teppei; Mizobuchi, Ritsuko; Sato, Hiroyuki

2017-12-01

Rice brown spot (BS), caused by Bipolaris oryzae , is one of the major diseases of rice in Japan. Quantitative resistance has been observed in local cultivars (e.g., CH45), but no economically useful resistant variety has been bred. Using simple sequence repeat (SSR) polymorphic markers, we conducted quantitative trait locus (QTL) analysis of BS resistance in backcross inbred lines (BILs) from a cross between indica CH45 (resistant) and japonica Koshihikari (susceptible). On the basis of field disease evaluations in 2015 and 2016, four QTLs contributing to BS resistance were identified on chromosomes 2 ( qBSR2-kc ), 7 ( qBSR7-kc ), 9 ( qBSR9-kc ), and 11 ( qBSR11-kc ). The 'CH45' alleles at qBSR2-kc , qBSR7-kc , and qBSR11-kc and the 'Koshihikari' allele at qBSR9-kc increased resistance. The major QTL qBSR11-kc explained 23.0%-25.9% of the total phenotypic variation. Two QTLs ( qBSR9-kc and qBSR11-kc ) were detected in both years, whereas the other two were detected only in 2016. Genetic markers flanking these four QTLs will be powerful tools for marker-assisted selection to improve BS resistance.

The relative contribution of target-site mutations in complex acaricide resistant phenotypes as assessed by marker assisted backcrossing in Tetranychus urticae.

PubMed

Riga, Maria; Bajda, Sabina; Themistokleous, Christos; Papadaki, Stavrini; Palzewicz, Maria; Dermauw, Wannes; Vontas, John; Leeuwen, Thomas Van

2017-08-23

The mechanisms underlying insecticide and acaricide resistance in insects and mites are often complex, including additive effects of target-site insensitivity, increased metabolism and transport. The extent to which target-site resistance mutations contribute to the resistance phenotype is, however, not well studied. Here, we used marker-assisted backcrossing to create 30 congenic lines carrying nine mutations (alone, or in combination in a few cases) associated with resistance to avermectins, pyrethroids, mite growth inhibitors and mitochondrial complex III inhibitors (QoI) in a polyphagous arthropod pest, the spider mite Tetranychus urticae. Toxicity tests revealed that mutations in the voltage-gated sodium channel, chitin synthase 1 and cytochrome b confer high levels of resistance and, when fixed in a population, these mutations alone can result in field failure of acaricide treatment. In contrast, although we confirmed the implication of mutations in glutamate-gated chloride channels in abamectin and milbemectin insensitivity, these mutations do not lead to the high resistance levels that are often reported in abamectin resistant strains of T. urticae. Overall, this study functionally validates reported target-site resistance mutations in T. urticae, by uncoupling them from additional mechanisms, allowing to finally investigate the strength of the conferred phenotype in vivo.

Why develop O. sativa x O. rufipogon chromosome segment substitution line libraries?

USDA-ARS?s Scientific Manuscript database

Transgressive variation has been observed in rice (Oryza sativa) as an increase in grain yield in advanced backcross mapping populations derived from crosses between several adapted O. sativa varieties and a single accession (IRGC105491) of the ancestral parent, O. rufipogon. The phenomena of hybrid...

Oryza rufipogon introgressions improve yield in the U.S. cultivar Jefferson

USDA-ARS?s Scientific Manuscript database

An advanced backcross (BC2) population was developed to explore the breeding value of the wild ancestral species O. rufipogon (IRGC 105491) in a cross with the tropical japonica US variety, cv Jefferson. Early generation selection eliminated lines which possessed undesirable traits such as dormancy,...

Development of a dense SNP-based linkage map of an apple rootstock progeny using the Malus Infinium whole genome genotyping array.

PubMed

Antanaviciute, Laima; Fernández-Fernández, Felicidad; Jansen, Johannes; Banchi, Elisa; Evans, Katherine M; Viola, Roberto; Velasco, Riccardo; Dunwell, Jim M; Troggio, Michela; Sargent, Daniel J

2012-05-25

A whole-genome genotyping array has previously been developed for Malus using SNP data from 28 Malus genotypes. This array offers the prospect of high throughput genotyping and linkage map development for any given Malus progeny. To test the applicability of the array for mapping in diverse Malus genotypes, we applied the array to the construction of a SNP-based linkage map of an apple rootstock progeny. Of the 7,867 Malus SNP markers on the array, 1,823 (23.2%) were heterozygous in one of the two parents of the progeny, 1,007 (12.8%) were heterozygous in both parental genotypes, whilst just 2.8% of the 921 Pyrus SNPs were heterozygous. A linkage map spanning 1,282.2 cM was produced comprising 2,272 SNP markers, 306 SSR markers and the S-locus. The length of the M432 linkage map was increased by 52.7 cM with the addition of the SNP markers, whilst marker density increased from 3.8 cM/marker to 0.5 cM/marker. Just three regions in excess of 10 cM remain where no markers were mapped. We compared the positions of the mapped SNP markers on the M432 map with their predicted positions on the 'Golden Delicious' genome sequence. A total of 311 markers (13.7% of all mapped markers) mapped to positions that conflicted with their predicted positions on the 'Golden Delicious' pseudo-chromosomes, indicating the presence of paralogous genomic regions or mis-assignments of genome sequence contigs during the assembly and anchoring of the genome sequence. We incorporated data for the 2,272 SNP markers onto the map of the M432 progeny and have presented the most complete and saturated map of the full 17 linkage groups of M. pumila to date. The data were generated rapidly in a high-throughput semi-automated pipeline, permitting significant savings in time and cost over linkage map construction using microsatellites. The application of the array will permit linkage maps to be developed for QTL analyses in a cost-effective manner, and the identification of SNPs that have been

Development of a dense SNP-based linkage map of an apple rootstock progeny using the Malus Infinium whole genome genotyping array

PubMed Central

2012-01-01

Background A whole-genome genotyping array has previously been developed for Malus using SNP data from 28 Malus genotypes. This array offers the prospect of high throughput genotyping and linkage map development for any given Malus progeny. To test the applicability of the array for mapping in diverse Malus genotypes, we applied the array to the construction of a SNP-based linkage map of an apple rootstock progeny. Results Of the 7,867 Malus SNP markers on the array, 1,823 (23.2%) were heterozygous in one of the two parents of the progeny, 1,007 (12.8%) were heterozygous in both parental genotypes, whilst just 2.8% of the 921 Pyrus SNPs were heterozygous. A linkage map spanning 1,282.2 cM was produced comprising 2,272 SNP markers, 306 SSR markers and the S-locus. The length of the M432 linkage map was increased by 52.7 cM with the addition of the SNP markers, whilst marker density increased from 3.8 cM/marker to 0.5 cM/marker. Just three regions in excess of 10 cM remain where no markers were mapped. We compared the positions of the mapped SNP markers on the M432 map with their predicted positions on the ‘Golden Delicious’ genome sequence. A total of 311 markers (13.7% of all mapped markers) mapped to positions that conflicted with their predicted positions on the ‘Golden Delicious’ pseudo-chromosomes, indicating the presence of paralogous genomic regions or mis-assignments of genome sequence contigs during the assembly and anchoring of the genome sequence. Conclusions We incorporated data for the 2,272 SNP markers onto the map of the M432 progeny and have presented the most complete and saturated map of the full 17 linkage groups of M. pumila to date. The data were generated rapidly in a high-throughput semi-automated pipeline, permitting significant savings in time and cost over linkage map construction using microsatellites. The application of the array will permit linkage maps to be developed for QTL analyses in a cost-effective manner, and

Feeding of soy protein isolate to rats during pregnancy and lactation suppresses formation of aberrant crypt foci in their progeny's colons: interaction of diet with fetal alcohol exposure

PubMed Central

Linz, Amanda L; Xiao, Rijin; Parker, James G; Simpson, Pippa M; Badger, Thomas M; Simmen, Frank A

2004-01-01

Soy protein isolate (SPI) in the diet may inhibit colon tumorigenesis. We examined azoxymethane (AOM)-induced aberrant crypt foci (ACF) in male rats in relation to lifetime, pre-weaning, or post-weaning dietary exposure to SPI and also within the context of fetal alcohol exposure. Pregnant Sprague Dawley rats were fed AIN-93G diets containing casein (20%, the control diet) or SPI (20%) as the sole protein source starting on gestation day 4 (GD 4). Progeny were weaned on postnatal day (PND) 21 to the same diet as their dams and were fed this diet until termination of the experiment at PND 138. Rats received AOM on PND 89 and 96. Lifetime (GD 4 to PND 138) feeding of SPI led to reduced frequency of ACF with 4 or more crypts in the distal colon. Progeny of dams fed SPI only during pregnancy and lactation or progeny fed SPI only after weaning exhibited similarly reduced frequency of large ACF in distal colon. Number of epithelial cells, in the distal colon, undergoing apoptosis was unaffected by diet. SPI reduced weight gain and adiposity, but these were not correlated with fewer numbers of large ACF. Lifetime SPI exposure similarly inhibited development of large ACF in Sprague Dawley rats whose dams were exposed to ethanol during pregnancy. In summary, feeding of SPI to rat dams during pregnancy and lactation suppresses numbers of large ACF in their progeny, implying a long-term or permanent change elicited by the maternal diet. Moreover, results support the use of ACF as an intermediate endpoint for elucidating effects of SPI and its biochemical constituents in colon cancer prevention in rats. PMID:15488141

On the difficulties of discriminating between major and minor hybrid male sterility factors in Drosophila by examining the segregation ratio of sterile and fertile sons in backcrossing experiments.

PubMed

Maside, X R; Naveira, H F

1996-10-01

The observation of segregation ratios of sterile and fertile males in offspring samples from backcrossed hybrid females is, in principle, a valid method to unveil the genetic basis of hybrid male sterility in Drosophila. When the female parent is heterozygous (hybrid) for a sterility factor with major effects, equal proportions of fertile and sterile sons are expected in her offspring. However, intact (not recombined) chromosome segments of considerable length are expected to give segregation ratios that can not be easily differentiated from the 1:1 ratio expected from a single factor. When the phenotypic character under analysis can be determined by combinations of minor factors from the donor species spanning a certain chromosome length, very large offspring samples may be needed to test this alternative hypothesis against the null hypothesis of a single major factor. This is particularly the case of hybrid male sterility determinants in Drosophila.

Phenotypic and Genotypic Analysis of In Vitro-Selected Artemisinin-Resistant Progeny of Plasmodium falciparum

PubMed Central

Tucker, Matthew S.; Mutka, Tina; Sparks, Kansas; Patel, Janus

2012-01-01

Emergence of artemisinin resistance in Cambodia highlights the importance of characterizing resistance to this class of drugs. Previously, intermediate levels of resistance in Plasmodium falciparum were generated in vitro for artelinic acid (AL) and artemisinin (QHS). Here we expanded on earlier selection efforts to produce levels of clinically relevant concentrations, and the resulting lines were characterized genotypically and phenotypically. Recrudescence assays determined the ability of resistant and parent lines to recover following exposure to clinically relevant levels of drugs. Interestingly, the parent clone (D6) tolerated up to 1,500 ng/ml QHS, but the resistant parasite, D6.QHS340×3, recovered following exposure to 2,400 ng/ml QHS. Resistant D6, W2, and TM91c235 parasites all exhibited elevated 50% inhibitory concentrations (IC50s) to multiple artemisinin drugs, with >3-fold resistance to QHS and AL; however, the degree of resistance obtained with standard methods was remarkably less than expected for parasite lines that recovered from 2,400-ng/ml drug pressure. A novel assay format with radiolabeled hypoxanthine demonstrated a greater degree of resistance in vitro than the standard SYBR green method. Analysis of merozoite number in resistant parasites found D6 and TM91c235 resistant progeny had significantly fewer merozoites than parent strains, whereas W2 resistant progeny had significantly more. Amplification of pfmdr1 increased proportionately to the increased drug levels tolerated by W2 and TM91c235, but not in resistant D6. In summary, we define the artemisinin resistance phenotype as a decrease in susceptibility to artemisinins along with the ability to recover from drug-induced dormancy following supraclinical concentrations of the drug. PMID:22083467

Long-term measurements of residential radon, thoron, and thoron progeny concentrations around the Chhatrapur placer deposit, a high background radiation area in Odisha, India.

PubMed

Omori, Yasutaka; Prasad, Ganesh; Sorimachi, Atsuyuki; Sahoo, Sarata Kumar; Ishikawa, Tetsuo; Vidya Sagar, Devulapalli; Ramola, Rakesh Chand; Tokonami, Shinji

2016-10-01

The Chhatrapur placer deposit is found in a high background radiation area which has been recently identified on the southeastern coast of India. Previously, some geochemical studies of this area were carried out to assess external dose from radionuclides-bearing heavy mineral sands. In this study, radon, thoron and thoron progeny concentrations were measured in about 100 dwellings during three seasons (autumn-winter, summer, and rainy) in a 10- to 12-month period and annual doses due to inhalation of them were evaluated. The measurements were made by passive-type radon-thoron discriminative detectors and thoron progeny detectors in which solid state nuclear track detectors were deployed. The results show that radon and thoron concentrations differ by one order of magnitude depending on exposure periods, while thoron progeny concentration is nearly constant throughout the year. Since thorium-rich sand is distributed in the studied area, exposure to thoron is equal to, or exceeds, exposure to radon and is not negligible for dose evaluation. Based on the measurements, doses due to inhalation of radon and thoron are evaluated as 0.1-1.6 mSv y -1 and 0.2-3.8 mSv y -1 , respectively. The total dose is 0.8-4.6 mSv y -1 , which is the same order of magnitude as the worldwide value. Copyright © 2016 Elsevier Ltd. All rights reserved.

Room model based Monte Carlo simulation study of the relationship between the airborne dose rate and the surface-deposited radon progeny.

PubMed

Sun, Kainan; Field, R William; Steck, Daniel J

2010-01-01

The quantitative relationships between radon gas concentration, the surface-deposited activities of various radon progeny, the airborne radon progeny dose rate, and various residential environmental factors were investigated through a Monte Carlo simulation study based on the extended Jacobi room model. Airborne dose rates were calculated from the unattached and attached potential alpha-energy concentrations (PAECs) using two dosimetric models. Surface-deposited (218)Po and (214)Po were significantly correlated with radon concentration, PAECs, and airborne dose rate (p-values <0.0001) in both non-smoking and smoking environments. However, in non-smoking environments, the deposited radon progeny were not highly correlated to the attached PAEC. In multiple linear regression analysis, natural logarithm transformation was performed for airborne dose rate as a dependent variable, as well as for radon and deposited (218)Po and (214)Po as predictors. In non-smoking environments, after adjusting for the effect of radon, deposited (214)Po was a significant positive predictor for one dose model (RR 1.46, 95% CI 1.27-1.67), while deposited (218)Po was a negative predictor for the other dose model (RR 0.90, 95% CI 0.83-0.98). In smoking environments, after adjusting for radon and room size, deposited (218)Po was a significant positive predictor for one dose model (RR 1.10, 95% CI 1.02-1.19), while a significant negative predictor for the other model (RR 0.90, 95% CI 0.85-0.95). After adjusting for radon and deposited (218)Po, significant increases of 1.14 (95% CI 1.03-1.27) and 1.13 (95% CI 1.05-1.22) in the mean dose rates were found for large room sizes relative to small room sizes in the different dose models.

Parvoviral Left-End Hairpin Ears Are Essential during Infection for Establishing a Functional Intranuclear Transcription Template and for Efficient Progeny Genome Encapsidation

PubMed Central

Li, Lei; Cotmore, Susan F.

2013-01-01

The 121-nucleotide left-end telomere of Minute Virus of Mice (MVM) can be folded into a Y-shaped hairpin with short axial ears that are highly conserved within genus Parvovirus. To explore their potential role(s) during infection, we constructed infectious plasmid clones that lacked one or other ear. Although these were nonviable when transfected into A9 cells, excision of the viral genome and DNA amplification appeared normal, and viral transcripts and proteins were expressed, but progeny virion production was minimal, supporting the idea of a potential role for the ears in genome packaging. To circumvent the absence of progeny that confounded further analysis of these mutants, plasmids were transfected into 293T cells both with and without an adenovirus helper construct, generating single bursts of progeny. These virions bound to A9 cells and were internalized but failed to initiate viral transcription, protein expression, or DNA replication. No defects in mutant virion stability or function could be detected in vitro. Significantly, mutant capsid gene expression and DNA replication could be rescued by coinfection with wild-type virions carrying a replication-competent, capsid-gene-replacement vector. To pinpoint where such complementation occurred, prior transfection of plasmids expressing only MVM nonstructural proteins was explored. NS1 alone, but not NS2, rescued transcription and protein expression from both P4 and P38 promoters, whereas NS1 molecules deleted for their C-terminal transactivation domain did not. These results suggest that the mutant virions reach the nucleus, uncoat, and are converted to duplex DNA but require an intact left-end hairpin structure to form the initiating transcription complex. PMID:23903839

A STUDY OF MEIOSIS IN THE PROGENY OF X-IRRADIATED LUZULA PURPUREA

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

Nordenskiold, H.

1963-01-01

In Luzula the chromosomes have diffuse or nonlocalized centromeres; thus, if the chromosomes are broken or rearranged by x-ray treatment, the changed chromosome patterns may survive through the mitotic cell divisions, on account of the centromeric action along the whole chromosomes. Hence, such plants with diffuse centromeres are able to survive and reach adult stages in spite of the fact that their chromosomes have been rearranged or broken by x-ray treatment of the seedlings. A study was made of plants selected from the progeny of material treated as seedlings with 1000 or 2500 r. Plants treated with stronger doses (5000more » to 10000 r) were almost or completely sterile. The chromosome patterns of the root tips of X/sub 2/ plants were investigated in order to find plants with desirable chrom-osome patterns for the meiotic investigation. The x-irradiated plants themselves showed intricate metaphasic configurations during meiosis. The separation of the multi-associations at first anaphase is cytologically equational, and in most cases without bridges. Migration of chromatids during second anaphase is also regular without lagging chromosomes, but chromosome sets of 4 tetrad cells usually become unbalanced, causing reduced fertility. The mitotic chromosome patterns of X/sub 2/ plants showed three categories of patterns: 2n = 6; most of these plants have all chromosomes the same size, but some of them possess one long and one short chromosome indicating a reciprocal translocation between two chromosomes; 2n = 7, with one of the original chromosomes fragmented into two pieces; and 2n = 8, with two of the original chromosomes fragmented into two pieces each. A study was made of meiosis in X/ sub 2/ plants with a cytologically observable rearrangement in the root tips, determined as a reciprocal progeny plants were obtained. Meiosis of X/sub 2/ plants heterozygous for one chromosome fragmented into two pieces, i.e., possessing 2n = 7 with five normal-sized and two

Assessment and genetic analysis of heavy metal content in rice grain using an Oryza sativa × O. rufipogon backcross inbred line population.

PubMed

Huang, De-Run; Fan, Ye-Yang; Hu, Biao-Lin; Xiao, Ye-Qing; Chen, Da-Zhou; Zhuang, Jie-Yun

2018-03-01

Heavy metal accumulation in rice is a growing concern for public health. Backcross inbred lines derived from an interspecific cross of Oryza sativa × O. rufipogon were grown in two distinct ecological locations (Hangzhou and Lingshui, China). The objective of this study was to characterise the contents of heavy metal in rice grains, and to identify quantitative trait loci (QTLs) for heavy metal contents. The contents of Ni, As, Pb, Cr and Hg in milled rice showed a significant decline as compared with those in brown rice, whereas the content of Cd showed little change. The concentration of heavy metal in rice grain varied greatly between the two environments. A total of 24 QTLs responsible for heavy metal contents were detected, including two for both the brown and milled rice, 13 for brown rice only, and nine for milled rice only. All the QTLs except two had the enhancing alleles derived from O. rufipogon. Sixteen QTLs were clustered in six chromosomal regions. Environmental variation plays an important role in the heavy metal contents in rice grain. QTLs detected in this study might be useful for breeding rice varieties with low heavy metal content. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Responses to two-way selection on growth in mass-spawned F1 progeny of Argopecten irradians concentricus (Say)

NASA Astrophysics Data System (ADS)

Wang, Hui; Liu, Jin; Li, Yanhong; Zhu, Xiaowen; Liu, Zhigang

2014-03-01

In the present study, the effect of one-generation divergent selection on the growth and survival of the bay scallop ( Argopecten irradians concentricus) was examined to evaluate the efficacy of a selection program currently being carried out in Beibu Bay in the South China Sea. A total of 146 adult scallops were randomly selected from the same cultured population of A. i. concentricus, and divided into two groups in shell length (anterior-posterior measurement): large (4.91-6.02 cm, n=74) and small (3.31-4.18 cm, n=72). At the same time, a control group was also randomly sampled (4.21-4.88 cm, n =80). Mass-spawned F 1 progenies from the three size groups were obtained and reared under identical conditions at all growth phases. The effects of two-way (or upward-downward) selection on fertilization rate, hatching rate, survival rate, daily growth in shell length and body weight were assessed in the three size groups. Results show that significant differences ( P<0.01) were found in hatching rate, survival rate and daily growth of F1 progenies, but not in fertilization rate ( P>0.05), among the three groups. The hatching rate, survival rate and daily growth of the progeny of large-sized parents were greater than those of the control group ( P<0.05), which in turn were larger than those of small-sized group ( P<0.05). Responses to selection by shell length and body weight were 0.32 ± 0.04 cm and 2.18 ± 0.05 g, respectively, for the upward selection, and -0.14 ± 0.03 cm and -2.77 ± 0.06 g, respectively, for the downward selection. The realized heritability estimates of shell length and body weight were 0.38 ± 0.06 cm and 0.22 ± 0.07 g for the upward selection, and 0.24 ± 0.06 cm and 0.37 ± 0.09 g for the downward selection, respectively. The change in growth by bidirectional selection suggests that high genetic variation may be present in the cultured bay scallop population in China.

Gene introgression into Coffea arabica by way of triploid hybrids (C. arabica x C. canephora).

PubMed

Herrera, J C; Combes, M C; Cortina, H; Alvarado, G; Lashermes, P

2002-12-01

Interspecific triploid hybrid plants between the tetraploid species Coffea arabica L. and the diploid species C. canephora P. were backcrossed to C. arabica. Although characterised by a low production and an important fruit dropping, all attempted crosses (ie, 6) generated BC(1) progenies. Flow cytometric analysis of the nuclear DNA content revealed that most of the BC1 individuals were nearly tetraploid. Among the male gametes produced by the interspecific triploid hybrids, those presenting a high number of chromosomes appeared strongly favoured. Only pollen mother cells having nearly 22 chromosomes were effective, the others leading to deficient endosperm and fruit dropping. Molecular markers (ie, microsatellite and AFLP) combined with evaluations of morphological characteristics and resistance to leaf rust were applied to verify the occurrence of gene transfer from C. canephora into C. arabica, and to estimate the amount of introgression present in BC(1) individuals. The results reveal a strong deficiency in the C. canephroa alleles indicating a severe counter-selection against the introgression of genetic material from C. canephora into C. arabica by way of triploid hybrids. However, introgressants displaying desirable traits such as a high resistance to leaf rust were obtained. The low level of introgression could be an advantage by facilitating the recovery of the recurrent parent and possibly reducing the number of required backcrosses. On the other hand, this could be a limitation when attempting the transfer of a complex trait or several simply inherited traits.

Inference of genetic diversity in popcorn S3 progenies.

PubMed

Pena, G F; do Amaral, A T; Ribeiro, R M; Ramos, H C C; Boechat, M S B; Santos, J S; Mafra, G S; Kamphorst, S H; de Lima, V J; Vivas, M; de Souza Filho, G A

2016-05-09

Molecular markers are a useful tool for identification of complementary heterotic groups in breeding programs aimed at the production of superior hybrids, particularly for crops such as popcorn in which heterotic groups are not well-defined. The objective of the present study was to analyze the genetic diversity of 47 genotypes of tropical popcorn to identify possible heterotic groups for the development of superior hybrids. Four genotypes of high genetic value were studied: hybrid IAC 125, strain P2, and varieties UENF 14 and BRS Angela. In addition, 43 endogamous S3 progenies obtained from variety UENF 14 were used. Twenty-five polymorphic SSR-EST markers were analyzed. A genetic distance matrix was obtained and the following molecular diversity parameters were estimated: number of alleles, number of effective alleles, polymorphism information content (PIC), observed and expected heterozygosities, Shannon diversity index, and coefficient of inbreeding. We found a moderate PIC and high diversity index, indicating that the studied population presents both good discriminatory ability and high informativeness for the utilized markers. The dendrogram built based on the dissimilarity matrix indicated six distinct groups. Our findings demonstrate the genetic diversity among the evaluated genotypes and provide evidence for heterotic groups in popcorn. Furthermore, the functional genetic diversity indicates that there are informative genetic markers for popcorn.

Late Maturation Steps Preceding Selective Nuclear Export and Egress of Progeny Parvovirus

PubMed Central

Wolfisberg, Raphael; Kempf, Christoph

2016-01-01

ABSTRACT Although the mechanism is not well understood, growing evidence indicates that the nonenveloped parvovirus minute virus of mice (MVM) may actively egress before passive release through cell lysis. We have dissected the late maturation steps of the intranuclear progeny with the aims of confirming the existence of active prelytic egress and identifying critical capsid rearrangements required to initiate the process. By performing anion-exchange chromatography (AEX), we separated intranuclear progeny particles by their net surface charges. Apart from empty capsids (EC), two distinct populations of full capsids (FC) arose in the nuclei of infected cells. The earliest population of FC to appear was infectious but, like EC, could not be actively exported from the nucleus. Further maturation of this early population, involving the phosphorylation of surface residues, gave rise to a second, late population with nuclear export potential. While capsid surface phosphorylation was strictly associated with nuclear export capacity, mutational analysis revealed that the phosphoserine-rich N terminus of VP2 (N-VP2) was dispensable, although it contributed to passive release. The reverse situation was observed for the incoming particles, which were dephosphorylated in the endosomes. Our results confirm the existence of active prelytic egress and reveal a late phosphorylation event occurring in the nucleus as a selective factor for initiating the process. IMPORTANCE In general, the process of egress of enveloped viruses is active and involves host cell membranes. However, the release of nonenveloped viruses seems to rely more on cell lysis. At least for some nonenveloped viruses, an active process before passive release by cell lysis has been reported, although the underlying mechanism remains poorly understood. By using the nonenveloped model parvovirus minute virus of mice, we could confirm the existence of an active process of nuclear export and further characterize the

Late Maturation Steps Preceding Selective Nuclear Export and Egress of Progeny Parvovirus.

PubMed

Wolfisberg, Raphael; Kempf, Christoph; Ros, Carlos

2016-06-01

Although the mechanism is not well understood, growing evidence indicates that the nonenveloped parvovirus minute virus of mice (MVM) may actively egress before passive release through cell lysis. We have dissected the late maturation steps of the intranuclear progeny with the aims of confirming the existence of active prelytic egress and identifying critical capsid rearrangements required to initiate the process. By performing anion-exchange chromatography (AEX), we separated intranuclear progeny particles by their net surface charges. Apart from empty capsids (EC), two distinct populations of full capsids (FC) arose in the nuclei of infected cells. The earliest population of FC to appear was infectious but, like EC, could not be actively exported from the nucleus. Further maturation of this early population, involving the phosphorylation of surface residues, gave rise to a second, late population with nuclear export potential. While capsid surface phosphorylation was strictly associated with nuclear export capacity, mutational analysis revealed that the phosphoserine-rich N terminus of VP2 (N-VP2) was dispensable, although it contributed to passive release. The reverse situation was observed for the incoming particles, which were dephosphorylated in the endosomes. Our results confirm the existence of active prelytic egress and reveal a late phosphorylation event occurring in the nucleus as a selective factor for initiating the process. In general, the process of egress of enveloped viruses is active and involves host cell membranes. However, the release of nonenveloped viruses seems to rely more on cell lysis. At least for some nonenveloped viruses, an active process before passive release by cell lysis has been reported, although the underlying mechanism remains poorly understood. By using the nonenveloped model parvovirus minute virus of mice, we could confirm the existence of an active process of nuclear export and further characterize the associated capsid

Assessment of physiological parameters in response to an endotoxin challenge in crossbred steer progeny sired by Brahman bulls that experienced prenatal transportation stress

USDA-ARS?s Scientific Manuscript database

The objective of this experiment was to assess physiological responses to an endotoxin challenge in crossbred male progeny whose Brahman sires experienced prenatal transportation stress (PS) in utero. Sixteen steers (PNS group) sired by 3 PS bulls (gestating dams were transported for 2 h at 60, 80, ...

Bronchial dysplasia induced by radiation in miners exposed to 222Rn progeny.

PubMed Central

Michaylov, M A; Pressyanov, D S; Kalinov, K B

1995-01-01

OBJECTIVES--To investigate whether sputum cytology can be used to monitor epithelial cell changes in groups at high risk of lung cancer from exposure to radiation. METHODS--Dysplasia of bronchial cells was investigated by means of sputum cytology in a group of 434 underground miners. 100 of them were not exposed, and 334 were exposed to 222Rn progeny at cumulative exposures < 450 working level months. RESULTS--The frequency of dysplasia in the exposed group was significantly higher than that in the not exposed group (P < 0.0001), and an exposure-response relation was found. This relation was different for smokers and non-smokers. CONCLUSIONS--Possibly the frequencies of dysplasia could be used to assess past exposures of groups of miners. This approach could be applied to cases where data on radiation monitoring are not available or are very scarce. Images p82-a PMID:7757171

Infection of hematopoietic stem cells by Leishmania infantum increases erythropoiesis and alters the phenotypic and functional profiles of progeny.

PubMed

Carvalho-Gontijo, Raquel; Moreira, Diana Raquel; Resende, Mariana; Costa-Silva, Matheus Fernandes; Peruhype-Magalhães, Vanessa; Ribeiro, Cláudia Maria Franco; Ribeiro, Daniel Dias; Silvestre, Ricardo; Cordeiro-da-Silva, Anabela; Martins-Filho, Olindo Assis; Teixeira-Carvalho, Andréa

2018-04-01

Immunosuppression is a well-established risk factor for Visceral Leishmaniasis. Post-immunosuppression leishmaniasis is characterized by an increase of parasite burden, hematopoietic disorders and unusual clinical manifestations. Although there are many reports on bone marrow findings in VL, less is known about the relationship between parasite dynamics in this organ and the function of either hematopoietic stem cells and progenitor cells themselves. In the present study, we tackle these issues using a new approach of infecting human stem cells derived from bone marrow with L. infantum. Using this strategy, we show that human hematopoietic stem cells (hHSC) are able to phagocytize L. infantum promastigotes and release modulatory and pro-inflammatory cytokines, mainly TNF-α. Our results demonstrated that L. infantum infection in vitro enhances hematopoiesis, favoring the development of erythrocitic lineage through a mechanism yet unknown. Moreover, we found that L. infantum infection alters the phenotypic profile of the hematopoietic progeny; modifying the surface markers expression of differentiated cells. Thus, our study represents a rare opportunity to monitor the in vitro differentiation of human stem cells experimentally infected by L. infantum to better understand the consequences of the infection on phenotypic and functional profile of the cell progeny. Copyright © 2017. Published by Elsevier Inc.

Time-Resolved Visualisation of Nearly-Native Influenza A Virus Progeny Ribonucleoproteins and Their Individual Components in Live Infected Cells

PubMed Central

Avilov, Sergiy; Magnus, Julie; Cusack, Stephen; Naffakh, Nadia

2016-01-01

Influenza viruses are a global health concern because of the permanent threat of novel emerging strains potentially capable of causing pandemics. Viral ribonucleoproteins (vRNPs) containing genomic RNA segments, nucleoprotein oligomers, and the viral polymerase, play a central role in the viral replication cycle. Our knowledge about critical events such as vRNP assembly and interactions with other viral and cellular proteins is poor and could be substantially improved by time lapse imaging of the infected cells. However, such studies are limited by the difficulty to achieve live-cell compatible labeling of active vRNPs. Previously we designed the first unimpaired recombinant influenza WSN-PB2-GFP11 virus allowing fluorescent labeling of the PB2 subunit of the viral polymerase (Avilov et al., J.Virol. 2012). Here, we simultaneously labeled the viral PB2 protein using the above-mentioned strategy, and virus-encoded progeny RNPs through spontaneous incorporation of transiently expressed NP-mCherry fusion proteins during RNP assembly in live infected cells. This dual labeling enabled us to visualize progeny vRNPs throughout the infection cycle and to characterize independently the mobility, oligomerization status and interactions of vRNP components in the nuclei of live infected cells. PMID:26978069

Stochastic dosimetry model for radon progeny in the rat lung.

PubMed

Winkler-HeiI, R; Hofmann, W; Hussain, M

2014-07-01

The stochastic dosimetry model presented here considers the distinctly asymmetric, stochastic branching pattern reported in morphometric measurements. This monopodial structure suggests that an airway diameter is a more appropriate morphometric parameter to classify bronchial dose distributions for inhaled radon progeny than the commonly assigned airway generation numbers. Bronchial doses were calculated for the typical exposure conditions reported for the Pacific Northwest National Laboratory rat inhalation studies, yielding an average bronchial dose of 7.75 mGy WLM(-1). If plotted as functions of airway generations, the resulting dose distributions are highest in the central bronchial airways, while significantly decreasing towards peripheral generations. However, if plotted as functions of airway diameters, doses are much more uniformly distributed among bronchial airways. The comparison between rat and human lungs indicates that dose conversion coefficients for the rat lung are higher than the corresponding values for the human lung by a factor of 1.34 for the experimental PNNL exposure conditions, and of 1.25 for typical human indoor conditions. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Genes Outside the Major Histocompatibility Complex Locus Are Linked to the Development of Thyroid Autoantibodies and Thyroiditis in NOD.H2h4 Mice

PubMed Central

Lesage, Sylvie; Collin, Roxanne; Banuelos, Bianca; Aliesky, Holly A.; Rapoport, Basil

2017-01-01

Thyroiditis and autoantibodies to thyroglobulin (TgAb) and thyroid peroxidase (TPOAb) develop spontaneously in NOD.H2h4 mice, a phenotype enhanced by dietary iodine. NOD.H2h4 mice were derived by introducing the major histocompatibility class (MHC) molecule I-Ak from B10.A(4R) mice to nonobese diabetic (NOD) mice. Apart from I-Ak, the genes responsible for the NOD.H2h4 phenotype are unknown. Extending serendipitous observations from crossing BALB/c to NOD.H2h4 mice, thyroid autoimmunity was investigated in both genders of the F1, F2, and the second-generation backcross of F1 to NOD.H2h4 (N2). Medium-density linkage analysis was performed on thyroid autoimmunity traits in F2 and N2 progeny. TgAb develop before TPOAb and were measured after 8 and 16 weeks of iodide exposure; TPOAb and thyroiditis were studied at 16 weeks. TgAb, TPOAb, and thyroiditis, absent in BALB/c and F1 mice, developed in most NOD.H2h4 and in more N2 than F2 progeny. No linkages were observed in F2 progeny, probably because of the small number of autoantibody-positive mice. In N2 progeny (equal numbers of males and females), a chromosome 17 locus is linked to thyroiditis and TgAb and is suggestively linked to TPOAb. This locus includes MHC region genes from B10.A(4R) mice (such as I-Ak and Tnf, the latter involved in thyrocyte apoptosis) and genes from NOD mice such as Satb1, which most likely plays a role in immune tolerance. In conclusion, MHC and non-MHC genes, encoded within the chromosome 17 locus from both B10.A(4R) and NOD strains, are most likely responsible for the Hashimoto disease–like phenotype of NOD.H2h4 mice. PMID:28323998

Genes Outside the Major Histocompatibility Complex Locus Are Linked to the Development of Thyroid Autoantibodies and Thyroiditis in NOD.H2h4 Mice.

PubMed

McLachlan, Sandra M; Lesage, Sylvie; Collin, Roxanne; Banuelos, Bianca; Aliesky, Holly A; Rapoport, Basil

2017-04-01

Thyroiditis and autoantibodies to thyroglobulin (TgAb) and thyroid peroxidase (TPOAb) develop spontaneously in NOD.H2h4 mice, a phenotype enhanced by dietary iodine. NOD.H2h4 mice were derived by introducing the major histocompatibility class (MHC) molecule I-Ak from B10.A(4R) mice to nonobese diabetic (NOD) mice. Apart from I-Ak, the genes responsible for the NOD.H2h4 phenotype are unknown. Extending serendipitous observations from crossing BALB/c to NOD.H2h4 mice, thyroid autoimmunity was investigated in both genders of the F1, F2, and the second-generation backcross of F1 to NOD.H2h4 (N2). Medium-density linkage analysis was performed on thyroid autoimmunity traits in F2 and N2 progeny. TgAb develop before TPOAb and were measured after 8 and 16 weeks of iodide exposure; TPOAb and thyroiditis were studied at 16 weeks. TgAb, TPOAb, and thyroiditis, absent in BALB/c and F1 mice, developed in most NOD.H2h4 and in more N2 than F2 progeny. No linkages were observed in F2 progeny, probably because of the small number of autoantibody-positive mice. In N2 progeny (equal numbers of males and females), a chromosome 17 locus is linked to thyroiditis and TgAb and is suggestively linked to TPOAb. This locus includes MHC region genes from B10.A(4R) mice (such as I-Ak and Tnf, the latter involved in thyrocyte apoptosis) and genes from NOD mice such as Satb1, which most likely plays a role in immune tolerance. In conclusion, MHC and non-MHC genes, encoded within the chromosome 17 locus from both B10.A(4R) and NOD strains, are most likely responsible for the Hashimoto disease-like phenotype of NOD.H2h4 mice. Copyright © 2017 Endocrine Society.

Potent L-lactic acid assimilation of the fermentative and heterothallic haploid yeast Saccharomyces cerevisiae NAM34-4C.

PubMed

Tomitaka, Masataka; Taguchi, Hisataka; Matsuoka, Masayoshi; Morimura, Shigeru; Kida, Kenji; Akamatsu, Takashi

2014-01-01

We screened an industrial thermotolerant Saccharomyces cerevisiae strain, KF7, as a potent lactic-acid-assimilating yeast. Heterothallic haploid strains KF7-5C and KF7-4B were obtained from the tetrads of the homothallic yeast strain KF7. The inefficient sporulation and poor spore viability of the haploid strains were improved by two strategies. The first strategy was as follows: (i) the KF7-5C was crossed with the laboratory strain SH6710; (ii) the progenies were backcrossed with KF7-5C three times; and (iii) the progenies were inbred three times to maintain a genetic background close to that of KF7. The NAM12 diploid between the cross of the resultant two strains, NAM11-9C and NAM11-13A, showed efficient sporulation and exhibited excellent growth in YPD medium (pH 3.5) at 35°C with 1.4-h generation time, indicating thermotolerance and acid tolerance. The second strategy was successive intrastrain crosses. The resultant two strains, KFG4-6B and KFG4-4B, showed excellent mating capacity. A spontaneous mutant of KFG4-6B, KFG4-6BD, showed a high growth rate with a generation time of 1.1 h in YPD medium (pH 3.0) at 35°C. The KFG4-6BD strain produced ascospores, which were crossed with NAM11-2C and its progeny to produce tetrads. These tetrads were crossed with KFG4-4B to produce NAM26-14A and NAM26-15A. The latter strain had a generation time of 1.6 h at 35°C in pH 2.5, thus exhibiting further thermotolerance and acid tolerance. A progeny from a cross of NAM26-14A and NAM26-15A yielded the strain NAM34-4C, which showed potent lactic acid assimilation and high transformation efficiency, better than those of a standard laboratory strain. Copyright © 2013 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Performance and genetic variation of big-leaf mahogany (Swietenia macrophylla King) in provenance and progeny trials in the Yucatan Peninsula of Mexico.

Treesearch

Kevyn E. Wightman; Sheila E. Ward; Jeremy P. Haggar; Bartolo Rodriguez Santiago; Jonathan P. Cornelius

2008-01-01

Stocks of the valuable big-leaf mahogany (Swietenia macrophylla King) are declining, and trials for growth and pest resistance are needed to select material for plantations. Seeds were collected from 67 open-pollinated trees from five provenances in the Yucatan Peninsula of Mexico and planted in three provenance/progeny trials in the state of Quintana Roo, Mexico, in...

Genic control of honey bee dance language dialect.

PubMed

Rinderer, T E; Beaman, L D

1995-10-01

Behavioural genetic analysis of honey bee dance language shows simple Mendelian genic control over certain dance dialect differences. Worker honey bees of one parent colony (yellow) changed from round to transition dances for foraging distances of 20 m and from transition to waggle dances at 40 m. Worker bees of the other parent colony (black) made these shifts at 30 m and 90 m, respectively. F1 colonies behaved identically to their yellow parent, suggesting dominance. Progeny of backcrossing between the F1 generation and the putative recessive black parent assorted to four classes, indicating that the dialect differences studied are regulated by genes at two unlinked loci, each having two alleles. Honey bee dance communication is complex and highly integrated behaviour. Nonetheless, analysis of a small element of this behaviour, variation in response to distance, suggests that dance communication is regulated by subsets consisting of simple genic systems.

Zebrafish exposure to environmentally relevant concentration of depleted uranium impairs progeny development at the molecular and histological levels

PubMed Central

Gombeau, Kewin; Murat El Houdigui, Sophia; Floriani, Magali; Camilleri, Virginie; Cavalie, Isabelle; Adam-Guillermin, Christelle

2017-01-01

Uranium is an actinide naturally found in the environment. Anthropogenic activities lead to the release of increasing amounts of uranium and depleted uranium (DU) in the environment, posing potential risks to aquatic organisms due to radiological and chemical toxicity of this radionucleide. Although environmental contaminations with high levels of uranium have already been observed, chronic exposures of non-human species to levels close to the environmental quality standards remain scarcely characterized. The present study focused on the identification of the molecular pathways impacted by a chronic exposure of zebrafish to 20 μg/L of DU during 10 days. The transcriptomic effects were evaluated by the use of the mRNAseq analysis in three organs of adult zebrafish, the brain the testis and the ovaries, and two developmental stages of the adult fish progeny, two-cells embryo and four-days larvae. The results highlight generic effects on the cell adhesion process, but also specific transcriptomic responses depending on the organ or the developmental stage investigated. The analysis of the transgenerational effects of DU-exposure on the four-day zebrafish larvae demonstrate an induction of genes involved in oxidative response (cat, mpx, sod1 and sod2), a decrease of expression of the two hatching enzymes (he1a and he1b), the deregulation of the expression of gene coding for the ATPase complex and the induction of cellular stress. Electron microscopy analysis of skeletal muscles on the four-days larvae highlights significant histological impacts on the ultrastructure of both the mitochondria and the myofibres. In addition, the comparison with the transcriptomic data obtained for the acetylcholine esterase mutant reveals the induction of protein-chaperons in the skeletal muscles of the progeny of fish chronically exposed to DU, pointing towards long lasting effects of this chemical in the muscles. The results presented in this study support the hypothesis that a chronic

Improvement of Basmati rice varieties for resistance to blast and bacterial blight diseases using marker assisted backcross breeding.

PubMed

Ellur, Ranjith K; Khanna, Apurva; Yadav, Ashutosh; Pathania, Sandeep; Rajashekara, H; Singh, Vikas K; Gopala Krishnan, S; Bhowmick, Prolay K; Nagarajan, M; Vinod, K K; Prakash, G; Mondal, Kalyan K; Singh, Nagendra K; Vinod Prabhu, K; Singh, Ashok K

2016-01-01

Marker assisted backcross breeding was employed to incorporate the blast resistance genes, Pi2 and Pi54 and bacterial blight (BB) resistance genes xa13 and Xa21 into the genetic background of Pusa Basmati 1121 (PB1121) and Pusa Basmati 6. Foreground selection for target gene(s) was followed by arduous phenotypic and background selection which fast-tracked the recovery of recurrent parent genome (RPG) to an extent of 95.8% in one of the near-isogenic lines (NILs) namely, Pusa 1728-23-33-31-56, which also showed high degree of resemblance to recurrent parent, PB6 in phenotype. The phenotypic selection prior to background selection provided an additional opportunity for identifying the novel recombinants viz., Pusa 1884-9-12-14 and Pusa 1884-3-9-175, superior to parental lines in terms of early maturity, higher yield and improved quality parameters. There was no significant difference between the RPG recovery estimated based on SSR or SNP markers, however, the panel of SNPs markers was considered as the better choice for background selection as it provided better genome coverage and included SNPs in the genic regions. Multi-location evaluation of NILs depicted their stable and high mean performance in comparison to the respective recurrent parents. The Pi2+Pi54 carrying NILs were effective in combating a pan-India panel of Magnaporthe oryzae isolates with high level of field resistance in northern, eastern and southern parts of India. Alongside, the PB1121-NILs and PB6-NILs carrying BB resistance genes xa13+Xa21 were resistant against Xanthomonas oryzae pv. oryzae races of north-western, southern and eastern parts of the country. Three of NILs developed in this study, have been promoted to final stage of testing during the ​Kharif 2015 in the Indian National Basmati Trial. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

MEASUREMENT OF RADON, THORON AND THEIR PROGENY IN DIFFERENT TYPES OF DWELLING IN ALMORA DISTRICT OF KUMAUN HIMALAYAN REGION.

PubMed

Singh, Kuldeep; Semwal, Poonam; Pant, Preeti; Gusain, G S; Joshi, Manish; Sapra, B K; Ramola, R C

2016-10-01

The indoor concentrations of radon ( 222 Rn), thoron ( 220 Rn) and their daughter products were measured in the dwellings of Almora district in Kumaun Himalaya, India using pin-hole dosemeters and deposition progeny sensors. The measurements were made in the residential houses built of mud, stone with cement plaster and cemented house during winter season. Average [geometric mean (GM) values] radon and thoron concentrations for all dwellings were found to be 99.82 and 79.70 Bq m -3 , respectively, while average equilibrium equivalent radon concentration and equilibrium equivalent thoron concentration (measured for the first time for this region) were measured at 35.22 and 2.52 Bq m -3 , respectively. Radon concentration (GM values) was found to be 110.73, 97.00 and 93.85 Bq m -3 for mud houses, stone with cemented plaster houses and cemented houses, respectively. On the other hand, thoron concentration values were 87.10, 75.79 and 75.68 Bq m -3 for cemented houses, mud houses and stone with cemented plaster houses, respectively. Interpretations have been made on the basis of measured radon/thoron and progeny concentration values with respect to the difference of construction material of the dwellings. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Inheritance of pericentric inversion in chromosome 7 through the three progenies and a newborn with congenital hydronephrosis diagnosed prenatally by fetal urine sampling.

PubMed

Demirhan, Osman; Ozcan, Kenan; Taştemir, Deniz; Demir, Cansun; Tunç, Erdal; Solğun, Hüseyin A; Güzel, Ali Irfan

2008-01-01

To report the inheritance of a pericentric inversion in chromosome 7 through the three progenies, congenital hydronephrosis, and recurrent miscarriages in an extended family. Case report. Medical Faculty of Cukurova University in Turkey. Referred by obstetrics and gynecology clinic. Fetal urine and lymphocytic karyotype. Chromosomal analysis from fetal urine and peripheral blood lymphocytes were performed according to standard cytogenetic methods. We assessed an extended family in which a large pericentric inversion in chromosome 7 is segregating; one of the three progenies with the karyotype 46,XY,inv(7)(p22;q22) was heterozygote for the inversion and presented with congenital hydronephrosis. His mother, mother's brother, grandfather, grandfather's brother, and his daughter were similar for the inversion. This case describes the further molecular characterization of these breakpoints on the short or long arm of chromosome 7(p22-q22). The inv(7) is also associated with fetal wastage and may be playing a role in the etiology of the family's miscarriages. These findings can be used in clinical genetics and may be an effective tool for reproductive guidance and genetic counseling.

Leaf physiology and biomass allocation of backcross hybrid American chestnut (Castanea dentata) seedlings in response to light and water availability.

PubMed

Brown, Caleb E; Mickelbart, Michael V; Jacobs, Douglass F

2014-12-01

Partial canopy cover promotes regeneration of many temperate forest trees, but the consequences of shading on seedling drought resistance are unclear. Reintroduction of blight-resistant American chestnut (Castanea dentata (Marsh.) Borkh.) into eastern North American forests will often occur on water-limited sites and under partial canopy cover. We measured leaf pre-dawn water potential (Ψpd), leaf gas exchange, and growth and biomass allocation of backcross hybrid American chestnut seedlings from three orchard sources grown under different light intensities (76, 26 and 8% full photosynthetically active radiation (PAR)) and subjected to well-watered or mid-season water-stressed conditions. Seedlings in the water-stress treatment were returned to well-watered conditions after wilting to examine recovery. Seedlings growing under medium- and high-light conditions wilted at lower leaf Ψpd than low-light seedlings. Recovery of net photosynthesis (Anet) and stomatal conductance (gs) was greater in low and medium light than in high light. Seed source did not affect the response to water stress or light level in most cases. Between 26 and 8% full PAR, light became limiting to the extent that the effects of water stress had no impact on some growth and morphological traits. We conclude that positive and negative aspects of shading on seedling drought tolerance and recovery are not mutually exclusive. Partial shade may help American chestnut tolerate drought during early establishment through effects on physiological conditioning. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Analysis of the 'A72' peach tree growth habit and its inheritance in progeny obtained from crosses of 'A72' with columnar peach trees

USDA-ARS?s Scientific Manuscript database

Since the first report of the 'A72' semi-dwarf peach tree (Nn) by Monet and Salesses (1975), little information has become available on this genotype. We evaluated the growth habit and verified the inheritance of 'A72' in a population of 220 progeny derived from self-pollination. Detailed tree and ...

Development and application of a complex numerical model and software for the computation of dose conversion factors for radon progenies.

PubMed

Farkas, Árpád; Balásházy, Imre

2015-04-01

A more exact determination of dose conversion factors associated with radon progeny inhalation was possible due to the advancements in epidemiological health risk estimates in the last years. The enhancement of computational power and the development of numerical techniques allow computing dose conversion factors with increasing reliability. The objective of this study was to develop an integrated model and software based on a self-developed airway deposition code, an own bronchial dosimetry model and the computational methods accepted by International Commission on Radiological Protection (ICRP) to calculate dose conversion coefficients for different exposure conditions. The model was tested by its application for exposure and breathing conditions characteristic of mines and homes. The dose conversion factors were 8 and 16 mSv WLM(-1) for homes and mines when applying a stochastic deposition model combined with the ICRP dosimetry model (named PM-A model), and 9 and 17 mSv WLM(-1) when applying the same deposition model combined with authors' bronchial dosimetry model and the ICRP bronchiolar and alveolar-interstitial dosimetry model (called PM-B model). User friendly software for the computation of dose conversion factors has also been developed. The software allows one to compute conversion factors for a large range of exposure and breathing parameters and to perform sensitivity analyses. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Impact of silvicultural treatment on chestnut seedling growth and survival

Treesearch

C.C. Pinchot; S.E. Schlarbaum; S.L. Clark; C.J. Schweitzer; A.M. Saxton; F. V. Hebard

2014-01-01

Putatively blight-resistant advanced backcross chestnut seedlings will soon be available for outplanting on a regional scale. Few studies have examined the importance of silvicultural treatment or seedling quality to chestnut reintroduction in the U.S. This paper examines results from a silvicultural study of high-quality chestnut seedlings on the Cumberland Plateau of...

Short- and long-term variability of radon progeny concentration in dwellings in the Czech Republic.

PubMed

Slezáková, M; Navrátilová Rovenská, K; Tomásek, L; Holecek, J

2013-03-01

In this paper, repeated measurements of radon progeny concentration in dwellings in the Czech Republic are described. Two distinct data sets are available: one based on present measurements in 170 selected dwellings in the Central Bohemian Pluton with a primary measurement carried out in the 1990s and the other based on 1920 annual measurements in 960 single-family houses in the Czech Republic in 1992 and repeatedly in 1993. The analysis of variance model with random effects is applied to data to evaluate the variability of measurements. The calculated variability attributable to repeated measurements is compared with results from other countries. In epidemiological studies, ignoring the variability of measurements may lead to biased estimates of risk of lung cancer.

Profiling sugar metabolism during fruit development in a peach progeny with different fructose-to-glucose ratios.

PubMed

Desnoues, Elsa; Gibon, Yves; Baldazzi, Valentina; Signoret, Véronique; Génard, Michel; Quilot-Turion, Bénédicte

2014-11-25

Fruit taste is largely affected by the concentration of soluble sugars and organic acids and non-negligibly by fructose concentration, which is the sweetest-tasting sugar. To date, many studies investigating the sugars in fruit have focused on a specific sugar or enzyme and often on a single variety, but only a few detailed studies addressing sugar metabolism both as a whole and dynamic system are available. In commercial peach fruit, sucrose is the main sugar, followed by fructose and glucose, which have similar levels. Interestingly, low fructose-to-glucose ratios have been observed in wild peach accessions. A cross between wild peach and commercial varieties offers an outstanding possibility to study fruit sugar metabolism. This work provides a large dataset of sugar composition and the capacities of enzymes that are involved in sugar metabolism during peach fruit development and its genetic diversity. A large fraction of the metabolites and enzymes involved in peach sugar metabolism were assayed within a peach progeny of 106 genotypes, of which one quarter displayed a low fructose-to-glucose ratio. This profiling was performed at six stages of growth using high throughput methods. Our results permit drawing a quasi-exhaustive scheme of sugar metabolism in peach. The use of a large number of genotypes revealed a remarkable robustness of enzymatic capacities across genotypes and years, despite strong variations in sugar composition, in particular the fructose-to-glucose ratio, within the progeny. A poor correlation was also found between the enzymatic capacities and the accumulation rates of metabolites. These results invalidate the hypothesis of the straightforward enzymatic control of sugar concentration in peach fruit. Alternative hypotheses concerning the regulation of fructose concentration are discussed based on experimental data. This work lays the foundation for a comprehensive study of the mechanisms involved in sugar metabolism in developing fruit.

Sorting of progeny coronavirus from condensed secretory proteins at the exit from the trans-Golgi network of AtT20 cells.

PubMed

Tooze, J; Tooze, S A; Fuller, S D

1987-09-01

Murine hepatitis virus (strain A59), (MHV-A59) is a coronavirus that buds into pre-Golgi compartments and then exploits the exocytic pathway of the host cell to reach the exterior. The fibroblastic cells in which replication of this virus is usually studied have only a constitutive exocytic pathway that the virus uses. MHV-A59 also infects, albeit inefficiently, AtT20 cells, murine pituitary tumor cells with a regulated as well as a constitutive exocytic pathway. Here we examine AtT20 cells at early times after the infection, when the Golgi apparatus retains its morphological and biochemical integrity. We observe that progeny coronavirus and secretory protein destined for the secretory granules of the regulated exocytic pathway traverse the same Golgi stacks and accumulate in the trans-Golgi network. Their pathways diverge at this site, the condensed secretory proteins including the ACTH going to the secretory granules and the coronavirus to post-Golgi transport vesicles devoid of ACTH. On very rare occasions there is missorting such that aggregates of condensed secretory proteins and viruses occur together in post-Golgi vesicles. We conclude that the constitutive and regulated exocytic pathways, identified respectively by the progeny virions and the secretory protein ACTH, diverge at the exit from the trans-Golgi network.

Haldane’s Rule Is Linked to Extraordinary Sex Ratios and Sperm Length in Stalk-Eyed Flies

PubMed Central

Wilkinson, Gerald S.; Christianson, Sarah J.; Brand, Cara L.; Ru, George; Shell, Wyatt

2014-01-01

We use three allopatric populations of the stalk-eyed fly Teleopsis dalmanni from Southeast Asia to test two predictions made by the sex chromosome drive hypothesis for Haldane’s rule. The first is that modifiers that suppress or enhance drive should evolve rapidly and independently in isolated populations. The second is that drive loci or modifiers should also cause sterility in hybrid males. We tested these predictions by assaying the fertility of 2066 males derived from backcross experiments involving two pairs of populations and found that the proportion of mated males that fail to produce any offspring ranged from 38 to 60% among crosses with some males producing strongly female-biased or male-biased sex ratios. After genotyping each male at 25–28 genetic markers we found quantitative trait loci (QTL) that jointly influence male sterility, sperm length, and biased progeny sex ratios in each pair of populations, but almost no shared QTL between population crosses. We also discovered that the extant XSR chromosome has no effect on sex ratio or sterility in these backcross males. Whether shared QTL are caused by linkage or pleiotropy requires additional study. Nevertheless, these results indicate the presence of a “cryptic” drive system that is currently masked by suppressing elements that are associated with sterility and sperm length within but not between populations and, therefore, must have evolved since the populations became isolated, i.e., in <100,000 years. We discuss how genes that influence sperm length may contribute to hybrid sterility. PMID:25164880

Targeted introgression of a wheat stem rust resistance gene by DNA marker-assisted chromosome engineering.

PubMed

Niu, Zhixia; Klindworth, Daryl L; Friesen, Timothy L; Chao, Shiaoman; Jin, Yue; Cai, Xiwen; Xu, Steven S

2011-04-01

Chromosome engineering is a useful strategy for transfer of alien genes from wild relatives into modern crops. However, this strategy has not been extensively used for alien gene introgression in most crops due to low efficiency of conventional cytogenetic techniques. Here, we report an improved scheme of chromosome engineering for efficient elimination of a large amount of goatgrass (Aegilops speltoides) chromatin surrounding Sr39, a gene that provides resistance to multiple stem rust races, including Ug99 (TTKSK) in wheat. The wheat ph1b mutation, which promotes meiotic pairing between homoeologous chromosomes, was employed to induce recombination between wheat chromosome 2B and goatgrass 2S chromatin using a backcross scheme favorable for inducing and detecting the homoeologous recombinants with small goatgrass chromosome segments. Forty recombinants with Sr39 with reduced surrounding goatgrass chromatin were quickly identified from 1048 backcross progenies through disease screening and molecular marker analysis. Four of the recombinants carrying Sr39 with a minimal amount of goatgrass chromatin (2.87-9.15% of the translocated chromosomes) were verified using genomic in situ hybridization. Approximately 97% of the goatgrass chromatin was eliminated in one of the recombinants, in which a tiny goatgrass chromosome segment containing Sr39 was retained in the wheat genome. Localization of the goatgrass chromatin in the recombinants led to rapid development of three molecular markers tightly linked to Sr39. The new wheat lines and markers provide useful resources for the ongoing global effort to combat Ug99. This study has demonstrated great potential of chromosome engineering in genome manipulation for plant improvement.

Coagulation effect on the activity size distributions of long lived radon progeny aerosols and its application to atmospheric residence time estimation techniques.

PubMed

Anand, S; Mayya, Y S

2015-03-01

The long lived naturally occurring radon progeny species in the atmosphere, namely (210)Pb, (210)Bi and (210)Po, have been used as important tracers for understanding the atmospheric mixing processes and estimating aerosol residence times. Several observations in the past have shown that the activity size distribution of these species peaks at larger particle sizes as compared to the short lived radon progeny species - an effect that has been attributed to the process of coagulation of the background aerosols to which they are attached. To address this issue, a mathematical equation is derived for the activity-size distribution of tracer species by formulating a generalized distribution function for the number of tracer atoms present in coagulating background particles in the presence of radioactive decay and removal. A set of these equations is numerically solved for the progeny chain using Fuchs coagulation kernel combined with a realistic steady-state aerosol size spectrum that includes nucleation, accumulation and coarse mode components. The important findings are: (i) larger shifts in the modal sizes of (210)Pb and (210)Po at higher aerosol concentrations such as that found in certain Asian urban regions (ii) enrichment of tracer specific activity on particles as compared to that predicted by pure attachment laws (iii) sharp decline of daughter-to-parent activity ratios for decreasing particle sizes. The implication of the results to size-fractionated residence time estimation techniques is highlighted. A coagulation corrected graphical approach is presented for estimating the residence times from the size-segregated activity ratios of (210)Bi and (210)Po with respect to (210)Pb. The discrepancy between the residence times predicted by conventional formula and the coagulation corrected approach for specified activity ratios increases at higher atmospheric aerosol number concentrations (>10(10) #/m(3)) for smaller sizes (<1 μm). The results are further

Potential for amelioration of aflatoxin B1-induced immunotoxic effects in progeny of White Leghorn breeder hens co-exposed to vitamin E.

PubMed

Khan, Wajid Arshad; Khan, Muhammad Zargham; Khan, Ahrar; Ul Hassan, Zahoor; Saleemi, Muhammad Kashif

2014-01-01

This study was designed to evaluate the protective activity of Vitamin E (Vit E) on the immunotoxic effects induced by aflatoxin B1 (AFB1) in the progeny of breeder hens. For this purpose, 192 White Leghorn (WL) layer breeder hens were divided into 12 groups (A-L) and then fed test diets for either 1, 2 or 3 weeks. Group A was kept on basal feed (2900 Kcal/kg metabolizable energy) and served as control, while group B was offered a feed supplemented with Vit E at 100 mg/Kg. Groups C-G were offered feed containing 0.1, 0.5, 2.5, 5.0, and 10.0 mg/Kg AFB1, respectively, whereas groups H-L were offered the same dietary levels of AFB1 along with 100 mg/Kg Vit E supplementation. Hatching eggs were shifted to an incubator on a weekly basis to get progeny chicks. Hatched chicks in each group were maintained on basal ration and then subjected to different immunological assays. Lymphoproliferative responses (against PHA-P), antibody titers (against SRBC), oxidative damage to RBC, as well as phagocytic and nitrite production potential of the peritoneal macrophages from the chicks, were all adversely impacted by hen exposure to the higher doses of AFB1 or by increased intake (time) by the hens at a given dose of the toxin. No consistent ameliorative effects from Vit E were noted in these studies, i.e. effects seen against lower AFB1 doses were no longer apparent with the highest doses of AFB1. As such, for now it can be concluded that, with this particular single dose level of Vit E, AFB1-associated immunotoxic effects in progeny chicks can potentially be mitigated by dietary intake of Vit E by their hen dams. However, this is clearly an outcome that is driven by the level of the mycotoxin present in the feed. Future studies need to examine what impact higher Vit E doses than those employed herein might have in these ameliorative outcomes.

Long-term measurements of radon, thoron and their airborne progeny in 25 schools in Republic of Srpska.

PubMed

Ćurguz, Z; Stojanovska, Z; Žunić, Z S; Kolarž, P; Ischikawa, T; Omori, Y; Mishra, R; Sapra, B K; Vaupotič, J; Ujić, P; Bossew, P

2015-10-01

This article reports results of the first investigations on indoor radon, thoron and their decay products concentration in 25 primary schools of Banja Luka, capital city of Republic Srpska. The measurements have been carried out in the period from May 2011 to April 2012 using 3 types of commercially available nuclear track detectors, named: long-term radon monitor (GAMMA 1)- for radon concentration measurements (C(Rn)); radon-thoron discriminative monitor (RADUET) for thoron concentration measurements (C(Tn)); while equilibrium equivalent radon concentration (EERC) and equilibrium equivalent thoron concentrations (EETC) measured by Direct Radon Progeny Sensors/Direct Thoron Progeny Sensors (DRPS/DTPS) were exposed in the period November 2011 to April 2012. In each school the detectors were deployed at 10 cm distance from the wall. The obtained geometric mean concentrations were C(Rn) = 99 Bq m(-3) and C(Tn) = 51 Bq m(-3) for radon and thoron gases respectively. Those for equilibrium equivalent radon concentration (EERC) and equilibrium equivalent thoron concentrations (EETC) were 11.2 Bq m(-3) and 0.4 Bq m(-3), respectively. The correlation analyses showed weak relation only between C(Rn) and C(Tn) as well as between C(Tn) and EETC. The influence of the school geographical locations and factors linked to buildings characteristic in relation to measured concentrations were tested. The geographical location and floor level significantly influence C(Rn) while C(Tn) depend only from building materials (ANOVA, p ≤ 0.05). The obtained geometric mean values of the equilibrium factors were 0.123 for radon and 0.008 for thoron. Copyright © 2015 Elsevier Ltd. All rights reserved.

Indices estimated using REML/BLUP and introduction of a super-trait for the selection of progenies in popcorn.

PubMed

Vittorazzi, C; Amaral Junior, A T; Guimarães, A G; Viana, A P; Silva, F H L; Pena, G F; Daher, R F; Gerhardt, I F S; Oliveira, G H F; Pereira, M G

2017-09-27

Selection indices commonly utilize economic weights, which become arbitrary genetic gains. In popcorn, this is even more evident due to the negative correlation between the main characteristics of economic importance - grain yield and popping expansion. As an option in the use of classical biometrics as a selection index, the optimal procedure restricted maximum likelihood/best linear unbiased predictor (REML/BLUP) allows the simultaneous estimation of genetic parameters and the prediction of genotypic values. Based on the mixed model methodology, the objective of this study was to investigate the comparative efficiency of eight selection indices estimated by REML/BLUP for the effective selection of superior popcorn families in the eighth intrapopulation recurrent selection cycle. We also investigated the efficiency of the inclusion of the variable "expanded popcorn volume per hectare" in the most advantageous selection of superior progenies. In total, 200 full-sib families were evaluated in two different areas in the North and Northwest regions of the State of Rio de Janeiro, Brazil. The REML/BLUP procedure resulted in higher estimated gains than those obtained with classical biometric selection index methodologies and should be incorporated into the selection of progenies. The following indices resulted in higher gains in the characteristics of greatest economic importance: the classical selection index/values attributed by trial, via REML/BLUP, and the greatest genotypic values/expanded popcorn volume per hectare, via REML. The expanded popcorn volume per hectare characteristic enabled satisfactory gains in grain yield and popping expansion; this characteristic should be considered super-trait in popcorn breeding programs.

Recent advances in lineage differentiation from stem cells: hurdles and opportunities?

PubMed Central

Terryn, Joke; Tricot, Tine; Gajjar, Madhavsai; Verfaillie, Catherine

2018-01-01

Pluripotent stem cells have the property of long-term self-renewal and the potential to give rise to descendants of the three germ layers and hence all mature cells in the human body. Therefore, they hold the promise of offering insight not only into human development but also for human disease modeling and regenerative medicine. However, the generation of mature differentiated cells that closely resemble their in vivo counterparts remains challenging. Recent advances in single-cell transcriptomics and computational modeling of gene regulatory networks are revealing a better understanding of lineage commitment and are driving modern genome editing approaches. Additional modification of the chemical microenvironment, as well as the use of bioengineering tools to recreate the cellular, extracellular matrix, and physical characteristics of the niche wherein progenitors and mature cells reside, is now being used to further improve the maturation and functionality of stem cell progeny. PMID:29552337

Girardia dorotocephala transcriptome sequence, assembly, and validation through characterization of piwi homologs and stem cell progeny markers.

PubMed

Almazan, Eugene Matthew P; Lesko, Sydney L; Markey, Michael P; Rouhana, Labib

2018-01-15

Planarian flatworms are popular models for the study of regeneration and stem cell biology in vivo. Technical advances and increased availability of genetic information have fueled the discovery of molecules responsible for stem cell pluripotency and regeneration in flatworms. Unfortunately, most of the planarian research performed worldwide utilizes species that are not natural habitants of North America, which limits their availability to newcomer laboratories and impedes their distribution for educational activities. In order to circumvent these limitations and increase the genetic information available for comparative studies, we sequenced the transcriptome of Girardia dorotocephala, a planarian species pandemic and commercially available in North America. A total of 254,802,670 paired sequence reads were obtained from RNA extracted from intact individuals, regenerating fragments, as well as freshly excised auricles of a clonal line of G. dorotocephala (MA-C2), and used for de novo assembly of its transcriptome. The resulting transcriptome draft was validated through functional analysis of genetic markers of stem cells and their progeny in G. dorotocephala. Akin to orthologs in other planarian species, G. dorotocephala Piwi1 (GdPiwi1) was found to be a robust marker of the planarian stem cell population and GdPiwi2 an essential component for stem cell-driven regeneration. Identification of G. dorotocephala homologs of the early stem cell descendent marker PROG-1 revealed a family of lysine-rich proteins expressed during epithelial cell differentiation. Sequences from the MA-C2 transcriptome were found to be 98-99% identical to nucleotide sequences from G. dorotocephala populations with different chromosomal number, demonstrating strong conservation regardless of karyotype evolution. Altogether, this work establishes G. dorotocephala as a viable and accessible option for analysis of gene function in North America. Copyright © 2017 The Authors. Published by

Girardia dorotocephala transcriptome sequence, assembly, and validation through characterization of piwi homologs and stem cell progeny markers

PubMed Central

Almazan, Eugene Matthew P.; Lesko, Sydney L.; Markey, Michael P.; Rouhana, Labib

2017-01-01

Planarian flatworms are popular models for the study of regeneration and stem cell biology in vivo. Technical advances and increased availability of genetic information have fueled the discovery of molecules responsible for stem cell pluripotency and regeneration in flatworms. Unfortunately, most of the planarian research performed worldwide utilizes species that are not natural habitants of North America, which limits their availability to newcomer laboratories and impedes their distribution for educational activities. In order to circumvent these limitations and increase the genetic information available for comparative studies, we sequenced the transcriptome of Girardia dorotocephala, a planarian species pandemic and commercially available in North America. A total of 254,802,670 paired sequence reads were obtained from RNA extracted from intact individuals, regenerating fragments, as well as freshly excised auricles of a clonal line of G. dorotocephala (MA-C2), and used for de novo assembly of its transcriptome. The resulting transcriptome draft was validated through functional analysis of genetic markers of stem cells and their progeny in G. dorotocephala. Akin to orthologs in other planarian species, G. dorotocephala Piwi1 (GdPiwi1) was found to be a robust marker of the planarian stem cell population and GdPiwi2 an essential component for stem cell-driven regeneration. Identification of G. dorotocephala homologs of the early stem cell descendent marker PROG-1 revealed a family of lysine-rich proteins expressed during epithelial cell differentiation. Sequences from the MA-C2 transcriptome were found to be 98–99% identical to nucleotide sequences from G. dorotocephala populations with different chromosomal number, demonstrating strong conservation regardless of karyotype evolution. Altogether, this work establishes G. dorotocephala as a viable and accessible option for analysis of gene function in North America. PMID:28774726

Genetic mapping of a food preference gene in the silkworm, Bombyx mori, using restriction fragment length polymorphisms (RFLPs).

PubMed

Mase, Keisuke; Iizuka, Tetsuya; Yamamoto, Toshio; Okada, Eiji; Hara, Wajirou

2007-06-01

The domesticated silkworm, Bombyx mori, has strict food preferences and grows by feeding on mulberry leaves. However, "Sawa-J", an abnormal feeding habit strain selected from the genetic stock, feeds on an artificial diet without mulberry leaf powder. In this study, the food preference gene in Sawa-J was genetically identified using restriction fragment length polymorphisms (RFLPs) of a cDNA clone on each linkage group. Taking advantage of a lack of genetic recombination in females, reciprocal backcrossed F1 (BC1) progenies were independently prepared using a non-feeding strain, C108, as a mating partner of Sawa-J. Our results of linkage analysis and mapping proved that the feeding behavior is primarily controlled by a major recessive gene mapped at 20.2 cM on RFLP linkage group 9 (RFLG9), and clone e73 at a distance of 4.2 cM was found as the first linked molecular marker.

Genome-wide QTL mapping of saltwater tolerance in sibling species of Anopheles (malaria vector) mosquitoes

PubMed Central

Smith, H A; White, B J; Kundert, P; Cheng, C; Romero-Severson, J; Andolfatto, P; Besansky, N J

2015-01-01

Although freshwater (FW) is the ancestral habitat for larval mosquitoes, multiple species independently evolved the ability to survive in saltwater (SW). Here, we use quantitative trait locus (QTL) mapping to investigate the genetic architecture of osmoregulation in Anopheles mosquitoes, vectors of human malaria. We analyzed 1134 backcross progeny from a cross between the obligate FW species An. coluzzii, and its closely related euryhaline sibling species An. merus. Tests of 2387 markers with Bayesian interval mapping and machine learning (random forests) yielded six genomic regions associated with SW tolerance. Overlap in QTL regions from both approaches enhances confidence in QTL identification. Evidence exists for synergistic as well as disruptive epistasis among loci. Intriguingly, one QTL region containing ion transporters spans the 2Rop chromosomal inversion that distinguishes these species. Rather than a simple trait controlled by one or a few loci, our data are most consistent with a complex, polygenic mode of inheritance. PMID:25920668

Modeling intersubject variability of bronchial doses for inhaled radon progeny.

PubMed

Hofmann, Werner; Winkler-Heil, Renate; Hussain, Majid

2010-10-01

The main sources of intersubject variations considered in the present study were: (1) size and structure of nasal and oral passages, affecting extrathoracic deposition and, in further consequence, the fraction of the inhaled activity reaching the bronchial region; (2) size and asymmetric branching of the human bronchial airway system, leading to variations of diameters, lengths, branching angles, etc.; (3) respiratory parameters, such as tidal volume, and breathing frequency; (4) mucociliary clearance rates; and (5) thickness of the bronchial epithelium and depth of target cells, related to airway diameters. For the calculation of deposition fractions, retained surface activities, and bronchial doses, parameter values were randomly selected from their corresponding probability density functions, derived from experimental data, by applying Monte Carlo methods. Bronchial doses, expressed in mGy WLM-1, were computed for specific mining conditions, i.e., for defined size distributions, unattached fractions, and physical activities. Resulting bronchial dose distributions could be approximated by lognormal distributions. Geometric standard deviations illustrating intersubject variations ranged from about 2 in the trachea to about 7 in peripheral bronchiolar airways. The major sources of the intersubject variability of bronchial doses for inhaled radon progeny are the asymmetry and variability of the linear airway dimensions, the filtering efficiency of the nasal passages, and the thickness of the bronchial epithelium, while fluctuations of the respiratory parameters and mucociliary clearance rates seem to compensate each other.

Determination of photon emission probabilities for the main gamma-rays of ²²³Ra in equilibrium with its progeny.

PubMed

Pibida, L; Zimmerman, B; Fitzgerald, R; King, L; Cessna, J T; Bergeron, D E

2015-07-01

The currently published (223)Ra gamma-ray emission probabilities display a wide variation in the values depending on the source of the data. The National Institute of Standards and Technology performed activity measurements on a (223)Ra solution that was used to prepare several sources that were used to determine the photon emission probabilities for the main gamma-rays of (223)Ra in equilibrium with its progeny. Several high purity germanium (HPGe) detectors were used to perform the gamma-ray spectrometry measurements. Published by Elsevier Ltd.

Feeding dried distillers grains with solubles to lactating beef cows: impact of excess protein and fat on post-weaning progeny growth, glucose tolerance and carcass traits.

PubMed

Shee, C N; Lemenager, R P; Schoonmaker, J P

2018-04-01

Feeding dried distillers grains with solubles (DDGS), a feed high in fat and protein, to lactating beef cows can alter milk production and composition, resulting in improved pre-weaning growth of progeny. This alteration in milk profile may consequently alter the growth and carcass composition of the offspring after weaning. Therefore, Angus×Simmental steers (n=48) whose dams were fed one of two diets supplemented with either DDGS or soybean meal (CON) from calving to mid-lactation were placed in a feedlot to determine the effects of maternal nutrition during lactation on progeny development and carcass composition. Cow-calf pairs were allotted to two treatments at birth based on cow and calf BW, breed and age. Maternal diets were isocaloric (3.97 MJ/kg NEg) and consisted of rye hay supplemented with DDGS at 1% of BW (19.4% CP; 8.76% fat) or rye hay and corn silage supplemented with CON (11.7% CP; 2.06% fat). After conclusion of the treatments at 129 days postpartum, cow-calf pairs were comingled and managed as one group until weaning at 219 days postpartum. Steers were then transitioned to a common diet composed of 60% DDGS, 34% corn silage and 6% vitamin/mineral supplement and were placed indoors in individual pens with slatted floors. An intravenous glucose tolerance test (IVGTT) was performed 134 days after feedlot entry on 16 steers (CON, n=7; DDGS, n=9) to determine the effect of maternal diet on glucose and insulin sensitivity. Steers were slaughtered at a target BW of 645 kg. Categorical and continuous data were analyzed using the GLIMMIX and MIXED procedures of SAS, respectively. Steers from DDGS dams tended to be heavier on day 85 of feedlot finishing (P=0.09) compared with steers from CON dams. However, there were no differences in final weight, average daily gain, dry matter intake or efficiency (gain:feed, P⩾0.18). Maternal treatments did not affect progeny days on feed (P=0.15), despite a mean difference of 9 days in favor of DDGS. Glucose and

Agrobacterium tumefaciens Integrates Transfer DNA into Single Chromosomal Sites of Dimorphic Fungi and Yields Homokaryotic Progeny from Multinucleate Yeast

PubMed Central

Sullivan, Thomas D.; Rooney, Peggy J.; Klein, Bruce S.

2002-01-01

The dimorphic fungi Blastomyces dermatitidis and Histoplasma capsulatum cause systemic mycoses in humans and other animals. Forward genetic approaches to generating and screening mutants for biologically important phenotypes have been underutilized for these pathogens. The plant-transforming bacterium Agrobacterium tumefaciens was tested to determine whether it could transform these fungi and if the fate of transforming DNA was suited for use as an insertional mutagen. Yeast cells from both fungi and germinating conidia from B. dermatitidis were transformed via A. tumefaciens by using hygromycin resistance for selection. Transformation frequencies up to 1 per 100 yeast cells were obtained at high effector-to-target ratios of 3,000:1. B. dermatitidis and H. capsulatum ura5 lines were complemented with transfer DNA vectors expressing URA5 at efficiencies 5 to 10 times greater than those obtained using hygromycin selection. Southern blot analyses indicated that in 80% of transformants the transferred DNA was integrated into chromosomal DNA at single, unique sites in the genome. Progeny of B. dermatitidis transformants unexpectedly showed that a single round of colony growth under hygromycin selection or visible selection of transformants by lacZ expression generated homokaryotic progeny from multinucleate yeast. Theoretical analysis of random organelle sorting suggests that the majority of B. dermatitidis cells would be homokaryons after the ca. 20 generations necessary for colony formation. Taken together, the results demonstrate that A. tumefaciens efficiently transfers DNA into B. dermatitidis and H. capsulatum and has the properties necessary for use as an insertional mutagen in these fungi. PMID:12477790

YKL-40 is differentially expressed in human embryonic stem cells and in cell progeny of the three germ layers.

PubMed

Brøchner, Christian B; Johansen, Julia S; Larsen, Lars A; Bak, Mads; Mikkelsen, Hanne B; Byskov, Anne Grete; Andersen, Claus Yding; Møllgård, Kjeld

2012-03-01

The secreted glycoprotein YKL-40 participates in cell differentiation, inflammation, and cancer progression. High YKL-40 expression is reported during early human development, but its functions are unknown. Six human embryonic stem cell (hESC) lines were cultured in an atmosphere of low or high oxygen tension, in culture medium with or without basic fibroblast growth factor, and on feeder layers comprising mouse embryonic fibroblasts or human foreskin fibroblasts to evaluate whether hESCs and their progeny produced YKL-40 and to characterize YKL-40 expression during differentiation. Secreted YKL-40 protein and YKL-40 mRNA expression were measured by enzyme-linked immunosorbent assay (ELISA) and quantitative RT-PCR. Serial-sectioned colonies were stained for YKL-40 protein and for pluripotent hESC (OCT4, NANOG) and germ layer (HNF-3β, PDX1, CD34, p63, nestin, PAX6) markers. Double-labeling showed YKL-40 expression in OCT4-positive hESCs, PAX6-positive neuroectodermal cells, and HNF-3β-positive endodermal cells. The differentiating progeny showed strong YKL-40 expression. Abrupt transition between YKL-40 and OCT4-positive hESCs and YKL-40-positive ecto- and neuroectodermal lineages was observed within the same epithelial-like layer. YKL-40-positive cells within deeper layers lacked contact with OCT4-positive cells. YKL-40 may be important in initial cell differentiation from hESCs toward ectoderm and neuroectoderm, with retained epithelial morphology, whereas later differentiation into endoderm and mesoderm involves a transition into the deeper layers of the colony.

Quantitative trait loci for organ weights and adipose fat composition in Jersey and Limousin back-cross cattle finished on pasture or feedlot.

PubMed

Morris, C A; Bottema, C D K; Cullen, N G; Hickey, S M; Esmailizadeh, A K; Siebert, B D; Pitchford, W S

2010-12-01

A QTL study of live animal and carcass traits in beef cattle was carried out in New Zealand and Australia. Back-cross calves (385 heifers and 398 steers) were generated, with Jersey and Limousin backgrounds. This paper reports on weights of eight organs (heart, liver, lungs, kidneys, spleen, gastro-intestinal tract, fat, and rumen contents) and 12 fat composition traits (fatty acid (FA) percentages, saturated and monounsaturated FA subtotals, and fat melting point). The New Zealand cattle were reared and finished on pasture, whilst Australian cattle were reared on grass and finished on grain for at least 180 days. For organ weights and fat composition traits, 10 and 12 significant QTL locations (P<0.05), respectively, were detected on a genome-wide basis, in combined-sire or within-sire analyses. Seven QTL significant for organ weights were found at the proximal end of chromosome 2. This chromosome carries a variant myostatin allele (F94L), segregating from the Limousin ancestry, and this is a positional candidate for the QTL. Ten significant QTL for fat composition were found on chromosomes 19 and 26. Fatty acid synthase and stearoyl-CoA desaturase (SCD1), respectively, are positional candidate genes for these QTL. Two FA QTL found to be common to sire groups in both populations were for percentages of C14:0 and C14:1 (relative to all FAs) on chromosome 26, near the SCD1 candidate gene. © 2010 AgResearch Ltd, Animal Genetics © 2010 Stichting International Foundation for Animal Genetics.

Genetic mapping of 14 avirulence genes in an EU-B04 × 1639 progeny of Venturia inaequalis.

PubMed

Broggini, Giovanni A L; Bus, Vincent G M; Parravicini, Gabriella; Kumar, Satish; Groenwold, Remmelt; Gessler, Cesare

2011-02-01

Durable resistance to apple scab (Venturia inaequalis (Cke) Wint; anamorph Spilocaea pomi Fries) is one of the major goals of apple (Malus) breeding programs. Since current scab resistance breeding is heavily reliant on genes with gene-for-gene relationships, a good understanding of the genetic basis of host-pathogen interactions needs to be developed for this strategy to be successful. While the genomic organization of apple scab resistance genes has been studied extensively, little is known about the avirulence genes in the pathogen. The progeny of a cross of European V. inaequalis race (1) isolate EU-B04 and race (1,2,8,9) isolate 1639 was used to generate a genetic map based on microsatellite and AFLP markers, and investigated for inheritance of avirulence traits on 20 Malus accessions representing 17 scab resistance genes. The accessions comprised scab differential hosts (0), (1), (2), (8), and (9), and hosts carrying known as well as not previously reported secondary resistance genes, including some identified in crosses that have resistant accessions 'Geneva', 'Dolgo', Malus baccata jackii, M. micromalus, or 'Antonovka' in their pedigree. The latter genes appear to be narrow spectrum genes that showed gene-for-gene relationships as a segregation ratio of Avr:avr=1:1 was observed on 12 accessions, while a ratio of 3:1 was observed on five accessions and a ratio of 7:1 on one host. All progenies were shown to be pathogenic, as all of them were able to infect hosts (0) and (1). A genetic map consisting of 15 major linkage groups (LGs) and spanning 972cM was generated with the aid of 156 markers. The map position of 12 avirulence traits was determined: eight avirulence genes mapped into two separate clusters (1: AvrVdg2, AvrVv1, AvrVu1, AvrVrjrd; and 2: AvrVu2, AvrVh3.2, AvrVs1, AvrVu4), while four avirulence genes (AvrRvi8, AvrVv2, AvrVt57 and AvrVsv) mapped to different LGs. AvrRvi2 and AvrRvi9 also are genetically linked, but showed an interaction with Avr

Maternal high fat diet promotion of mammary tumor risk in adult progeny is associated with early expansion of mammary cancer stem-like cells and increased maternal oxidative environment

USDA-ARS?s Scientific Manuscript database

Many adult chronic diseases might be programmed during early life by maternal nutritional history. Here, we evaluated effects of maternal high fat diet on mammary gland development and tumor formation in adult progeny. Female Wnt-1 transgenic mice exposed to high fat (HFD, 45% kcal fat) or control C...

Modulatory role of sensory innervation on hair follicle stem cell progeny during wound healing of the rat skin.

PubMed

Martínez-Martínez, Eduardo; Galván-Hernández, Claudio I; Toscano-Márquez, Brenda; Gutiérrez-Ospina, Gabriel

2012-01-01

The bulge region of the hair follicle contains resident epithelial stem cells (SCs) that are activated and mobilized during hair growth and after epidermal wounding. However, little is known about the signals that modulate these processes. Clinical and experimental observations show that a reduced supply of sensory innervation is associated with delayed wound healing. Since axon terminals of sensory neurons are among the components of the bulge SC niche, we investigated whether these neurons are involved in the activation and mobilization of the hair stem cells during wound healing. We used neonatal capsaicin treatment to reduce sensory terminals in the rat skin and performed morphometric analyses using design-based stereological methods. Epithelial proliferation was analyzed by quantifying the number of bromodeoxyuridine-labeled (BrdU(+)) nuclei in the epidermis and hair follicles. After wounding, the epidermis of capsaicin-treated rats presented fewer BrdU(+) nuclei than in control rats. To assess SC progeny migration, we employed a double labeling protocol with iododeoxyuridine and chlorodeoxyuridine (IdU(+)/CldU(+)). The proportion of double-labeled cells was similar in the hair follicles of both groups at 32 h postwounding. IdU(+)/CldU(+) cell proportion increased in the epidermis of control rats and decreased in treated rats at 61 h postwounding. The epidermal volume immunostained for keratin 6 was greater in treated rats at 61 h. Confocal microscopy analysis revealed that substance P (SP) and calcitonin gene-related peptide (CGRP) receptor immunoreactivity were both present in CD34(+) and BrdU-retaining cells of the hair follicles. Our results suggest that capsaicin denervation impairs SC progeny egress from the hair follicles, a circumstance associated with a greater epidermal activation. Altogether, these phenomena would explain the longer times for healing in denervated skin. Thus, sensory innervation may play a functional role in the modulation of hair

Radioecological aftermath: Maternal transfer of anthropogenic radionuclides to shark progeny is sustained and enhanced well beyond maternal exposure.

PubMed

Jeffree, Ross A; Oberhaensli, Francois; Teyssie, Jean-Louis; Fowler, Scott W

2018-05-25

Cartilaginous dogfish Scyliorhinus canicula continued to transfer four anthropogenic radionuclides ( 65 Zn, 60 Co, 134 Cs and 241 Am) to their eggs for over six months, after two months of continued maternal exposure to radio-labelled food. Unexpectedly, rates of radionuclide transfers to eggs and their yolk & embryo during maternal depuration were equivalent for 60 Co and 241 Am, or even enhanced for 65 Zn and 134 Cs by factors of c.200-350%, over two-three months, compared to their maximal transfer rates at the end of the maternal uptake phase. These rates of maternal transfer of radionuclides to yolk & embryo were positively associated with their previously determined efficiencies of assimilation (AE) from ingested radio-labelled food. Thus progeny may be more exposed via maternal transfer to those radionuclides which have greater rates of maternal assimilation from food. As maternal depuration continued beyond 60-80 up to 180-200 days the transfers of all four radionuclides to eggs did diminish but were still substantial at mean values of 18% for 241 Am, 17% for 134 Cs and 9 and 8% for 60 Co and 65 Zn, respectively. In the yolk & embryo the mean rates of transfer over this period were further reduced for 241 Am (13.5%), 60 Co (2.5%) and 65 Zn (5.8%), but were still appreciable for 134 Cs at 56%. These results for S. canicula have demonstrated a potential enhanced radiological risk of extended duration due to the particular biokinetics of maternal transfer in this species. This study draws further attention to the current paucity of knowledge about the maternal: progeny transfer pathway, particularly in the context of the known heightened radio-sensitivity of early life stages in fish and other vertebrates, compared to later life stages. Copyright © 2018 Elsevier Ltd. All rights reserved.

Timing the tides: Genetic control of diurnal and lunar emergence times is correlated in the marine midge Clunio marinus

PubMed Central

2011-01-01

Background The intertidal zone of seacoasts, being affected by the superimposed tidal, diurnal and lunar cycles, is temporally the most complex environment on earth. Many marine organisms exhibit lunar rhythms in reproductive behaviour and some show experimental evidence of endogenous control by a circalunar clock, the molecular and genetic basis of which is unexplored. We examined the genetic control of lunar and diurnal rhythmicity in the marine midge Clunio marinus (Chironomidae, Diptera), a species for which the correct timing of adult emergence is critical in natural populations. Results We crossed two strains of Clunio marinus that differ in the timing of the diurnal and lunar rhythms of emergence. The phenotype distribution of the segregating backcross progeny indicates polygenic control of the lunar emergence rhythm. Diurnal timing of emergence is also under genetic control, and is influenced by two unlinked genes with major effects. Furthermore, the lunar and diurnal timing of emergence is correlated in the backcross generation. We show that both the lunar emergence time and its correlation to the diurnal emergence time are adaptive for the species in its natural environment. Conclusions The correlation implies that the unlinked genes affecting lunar timing and the two unlinked genes affecting diurnal timing could be the same, providing an unexpectedly close interaction of the two clocks. Alternatively, the genes could be genetically linked in a two-by-two fashion, suggesting that evolution has shaped the genetic architecture to stabilize adaptive combinations of lunar and diurnal emergence times by tightening linkage. Our results, the first on genetic control of lunar rhythms, offer a new perspective to explore their molecular clockwork. PMID:21599938

Timing the tides: genetic control of diurnal and lunar emergence times is correlated in the marine midge Clunio marinus.

PubMed

Kaiser, Tobias S; Neumann, Dietrich; Heckel, David G

2011-05-20

The intertidal zone of seacoasts, being affected by the superimposed tidal, diurnal and lunar cycles, is temporally the most complex environment on earth. Many marine organisms exhibit lunar rhythms in reproductive behaviour and some show experimental evidence of endogenous control by a circalunar clock, the molecular and genetic basis of which is unexplored. We examined the genetic control of lunar and diurnal rhythmicity in the marine midge Clunio marinus (Chironomidae, Diptera), a species for which the correct timing of adult emergence is critical in natural populations. We crossed two strains of Clunio marinus that differ in the timing of the diurnal and lunar rhythms of emergence. The phenotype distribution of the segregating backcross progeny indicates polygenic control of the lunar emergence rhythm. Diurnal timing of emergence is also under genetic control, and is influenced by two unlinked genes with major effects. Furthermore, the lunar and diurnal timing of emergence is correlated in the backcross generation. We show that both the lunar emergence time and its correlation to the diurnal emergence time are adaptive for the species in its natural environment. The correlation implies that the unlinked genes affecting lunar timing and the two unlinked genes affecting diurnal timing could be the same, providing an unexpectedly close interaction of the two clocks. Alternatively, the genes could be genetically linked in a two-by-two fashion, suggesting that evolution has shaped the genetic architecture to stabilize adaptive combinations of lunar and diurnal emergence times by tightening linkage. Our results, the first on genetic control of lunar rhythms, offer a new perspective to explore their molecular clockwork.

Genetic basis of HDL variation in 129/SvImJ and C57BL/6J mice: importance of testing candidate genes in targeted mutant mice.

PubMed

Su, Zhiguang; Wang, Xiaosong; Tsaih, Shirng-Wern; Zhang, Aihong; Cox, Allison; Sheehan, Susan; Paigen, Beverly

2009-01-01

To evaluate the effect of genetic background on high-density lipoprotein cholesterol (HDL) levels in Soat1(-/-) mice, we backcrossed sterol O-acyltransferase 1 (Soat1)(-/-) mice, originally reported to have elevated HDL levels, to C57BL/6 mice and constructed a congenic strain with only a small region (3.3Mb) of 129 alleles, specifically excluding the nearby apolipoprotein A-II (Apoa2) gene from 129. HDL levels in these Soat1(-/-) mice were no different from C57BL/6, indicating that the passenger gene Apoa2 caused the previously reported elevation of HDL in these Soat1(-/-) mice. Because many knockouts are made in strain 129 and then subsequently backcrossed into C57BL/6, it is important to identify quantitative trait loci (QTL) that differ between 129 and C57BL/6 so that one can guard against effects ascribed to a knockout but really caused by a passenger gene from 129. To provide such data, we generated 528 F(2) progeny from an intercross of 129S1/SvImJ and C57BL/6 and measured HDL concentrations in F(2) animals first fed chow and then atherogenic diet. A genome wide scan using 508 single-nucleotide polymorphisms (SNPs) identified 19 QTL, 2 of which were male specific and 2 were female specific. Using comparative genomics and haplotype analysis, we narrowed QTL on chromosomes 3, 5, 8, 17, and 18 to 0.5, 6.3, 2.6, 1.1, and 0.6 Mb, respectively. These data will serve as a reference for any effort to test the impact of candidate genes on HDL using a knockout strategy.

Targeted Introgression of a Wheat Stem Rust Resistance Gene by DNA Marker-Assisted Chromosome Engineering

PubMed Central

Niu, Zhixia; Klindworth, Daryl L.; Friesen, Timothy L.; Chao, Shiaoman; Jin, Yue; Cai, Xiwen; Xu, Steven S.

2011-01-01

Chromosome engineering is a useful strategy for transfer of alien genes from wild relatives into modern crops. However, this strategy has not been extensively used for alien gene introgression in most crops due to low efficiency of conventional cytogenetic techniques. Here, we report an improved scheme of chromosome engineering for efficient elimination of a large amount of goatgrass (Aegilops speltoides) chromatin surrounding Sr39, a gene that provides resistance to multiple stem rust races, including Ug99 (TTKSK) in wheat. The wheat ph1b mutation, which promotes meiotic pairing between homoeologous chromosomes, was employed to induce recombination between wheat chromosome 2B and goatgrass 2S chromatin using a backcross scheme favorable for inducing and detecting the homoeologous recombinants with small goatgrass chromosome segments. Forty recombinants with Sr39 with reduced surrounding goatgrass chromatin were quickly identified from 1048 backcross progenies through disease screening and molecular marker analysis. Four of the recombinants carrying Sr39 with a minimal amount of goatgrass chromatin (2.87–9.15% of the translocated chromosomes) were verified using genomic in situ hybridization. Approximately 97% of the goatgrass chromatin was eliminated in one of the recombinants, in which a tiny goatgrass chromosome segment containing Sr39 was retained in the wheat genome. Localization of the goatgrass chromatin in the recombinants led to rapid development of three molecular markers tightly linked to Sr39. The new wheat lines and markers provide useful resources for the ongoing global effort to combat Ug99. This study has demonstrated great potential of chromosome engineering in genome manipulation for plant improvement. PMID:21242535

Stochastic rat lung dosimetry for inhaled radon progeny: a surrogate for the human lung for lung cancer risk assessment.

PubMed

Winkler-Heil, R; Hussain, M; Hofmann, W

2015-05-01

Laboratory rats are frequently used in inhalation studies as a surrogate for human exposures. The objective of the present study was therefore to develop a stochastic dosimetry model for inhaled radon progeny in the rat lung, to predict bronchial dose distributions and to compare them with corresponding dose distributions in the human lung. The most significant difference between human and rat lungs is the branching structure of the bronchial tree, which is relatively symmetric in the human lung, but monopodial in the rat lung. Radon progeny aerosol characteristics used in the present study encompass conditions typical for PNNL and COGEMA rat inhalation studies, as well as uranium miners and human indoor exposure conditions. It is shown here that depending on exposure conditions and modeling assumptions, average bronchial doses in the rat lung ranged from 5.4 to 7.3 mGy WLM(-1). If plotted as a function of airway generation, bronchial dose distributions exhibit a significant maximum in large bronchial airways. If, however, plotted as a function of airway diameter, then bronchial doses are much more uniformly distributed throughout the bronchial tree. Comparisons between human and rat exposures indicate that rat bronchial doses are slightly higher than human bronchial doses by about a factor of 1.3, while lung doses, averaged over the bronchial (BB), bronchiolar (bb) and alveolar-interstitial (AI) regions, are higher by about a factor of about 1.6. This supports the current view that the rat lung is indeed an appropriate surrogate for the human lung in case of radon-induced lung cancers. Furthermore, airway diameter seems to be a more appropriate morphometric parameter than airway generations to relate bronchial doses to bronchial carcinomas.

Assessing the deposition of radon progeny from a uranium glass necklace.

PubMed

Hansen, M F; Moss, G R

2015-06-01

Could jewellery made from uranium glass beads pose an increased risk to skin cancer? The literature Eatough (Alpha-particle dosimetry for the basal layer of the skin and the radon progeny (218)Po and (214)Po. Phys. Med. Biol. 1997; 42: 1899-1911.) suggests that the alphas from the short-lived radon daughters, (218)Po and (214)Po, may reach the basal layer of the epidermis, which is believed to be important in the induction of skin cancers. The deposition of the alphas from the (218)Po and (214)Po daughters was investigated using PADC detector material. The expectation would be that no alpha particles would penetrate through the dead skin layer, assuming the average of 70 microns used in radiation protection, but the skin around the collar bone could potentially be thinner than the assumed average. It should be noticed that by inserting a slice of pig skin in between the necklace and the PADC, no great excess of alpha tracks were seen after 1 week of exposure in the freezer. There was, however, a clear signal through the pig skin from beta particles, confirming the potential of a uranium bead necklace posing a health risk. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Molecular and Functional Characterization of GR2-R1 Event Based Backcross Derived Lines of Golden Rice in the Genetic Background of a Mega Rice Variety Swarna

PubMed Central

Bollinedi, Haritha; S., Gopala Krishnan; Prabhu, Kumble Vinod; Singh, Nagendra Kumar; Mishra, Sushma; Khurana, Jitendra P.; Singh, Ashok Kumar

2017-01-01

Homozygous Golden Rice lines developed in the background of Swarna through marker assisted backcross breeding (MABB) using transgenic GR2-R1 event as a donor for the provitamin A trait have high levels of provitamin A (up to 20 ppm) but are dwarf with pale green leaves and drastically reduced panicle size, grain number and yield as compared to the recurrent parent, Swarna. In this study, we carried out detailed morphological, biochemical and molecular characterization of these lines in a quest to identify the probable reasons for their abnormal phenotype. Nucleotide blast analysis with the primer sequences used to amplify the transgene revealed that the integration of transgene disrupted the native OsAux1 gene, which codes for an auxin transmembrane transporter protein. Real time expression analysis of the transgenes (ZmPsy and CrtI) driven by endosperm-specific promoter revealed the leaky expression of the transgene in the vegetative tissues. We propose that the disruption of OsAux1 disturbed the fine balance of plant growth regulators viz., auxins, gibberellic acid and abscisic acid, leading to the abnormalities in the growth and development of the lines homozygous for the transgene. The study demonstrates the conserved roles of OsAux1 gene in rice and Arabidopsis. PMID:28068433

Molecular and Functional Characterization of GR2-R1 Event Based Backcross Derived Lines of Golden Rice in the Genetic Background of a Mega Rice Variety Swarna.

PubMed

Bollinedi, Haritha; S, Gopala Krishnan; Prabhu, Kumble Vinod; Singh, Nagendra Kumar; Mishra, Sushma; Khurana, Jitendra P; Singh, Ashok Kumar

2017-01-01

Homozygous Golden Rice lines developed in the background of Swarna through marker assisted backcross breeding (MABB) using transgenic GR2-R1 event as a donor for the provitamin A trait have high levels of provitamin A (up to 20 ppm) but are dwarf with pale green leaves and drastically reduced panicle size, grain number and yield as compared to the recurrent parent, Swarna. In this study, we carried out detailed morphological, biochemical and molecular characterization of these lines in a quest to identify the probable reasons for their abnormal phenotype. Nucleotide blast analysis with the primer sequences used to amplify the transgene revealed that the integration of transgene disrupted the native OsAux1 gene, which codes for an auxin transmembrane transporter protein. Real time expression analysis of the transgenes (ZmPsy and CrtI) driven by endosperm-specific promoter revealed the leaky expression of the transgene in the vegetative tissues. We propose that the disruption of OsAux1 disturbed the fine balance of plant growth regulators viz., auxins, gibberellic acid and abscisic acid, leading to the abnormalities in the growth and development of the lines homozygous for the transgene. The study demonstrates the conserved roles of OsAux1 gene in rice and Arabidopsis.

γ-H2AX/53BP1/pKAP-1 foci and their linear tracks induced by in vitro exposure to radon and its progeny in human peripheral blood lymphocytes

PubMed Central

Ding, Defang; Zhang, Yaping; Wang, Jing; Wang, Xufei; Fan, Dunhuang; He, Linfeng; Zhang, Xuxia; Gao, Yun; Li, Qiang; Chen, Honghong

2016-01-01

The biodosimetric information is critical for evaluating the human health hazards caused by radon and its progeny. Here, we demonstrated that the formation of phosphorylated histone variant H2AX (γ-H2AX), p53-binding protein 1 (53BP1) and phosphorylated KRAB-associated protein 1 (pKAP-1) foci and their linear tracks in human peripheral blood lymphocytes (HPBLs) in vitro exposed to radon and its progeny were dependent on the cumulative absorbed dose of radon exposure but was unrelated to the concentration of radon. Among them, γ-H2AX foci and its linear tracks were the most sensitive indicators with the lowest estimable cumulative absorbed dose of 1.74 mGy from their linear dose-response curves and sustained for 12 h after termination of radon exposure. In addition, three types of foci showed an overdispersed non-Poisson distribution in HPBLs. The ratios of pKAP-1/γ-H2AX foci co-localization, 53BP1/γ-H2AX foci co-localization and 53BP1/pKAP-1 foci co-localization were significantly increased in HPBLs exposed to radon while they were unrelated to the cumulative dose of radon exposure, suggesting that γ-H2AX, pKAP-1 and 53BP1 play an important role in the repair of heterochromatic double-strand breaks. Altogether, our findings provide an experimental basis for estimating the biological dose of internal α-particle irradiation from radon and its progeny exposure in humans. PMID:27922110

Campylobacter epidemiology from breeders to their progeny in Eastern Spain.

PubMed

Ingresa-Capaccioni, S; Jiménez-Trigos, E; Marco-Jiménez, F; Catalá, P; Vega, S; Marin, C

2016-03-01

While horizontal transmission is a route clearly linked to the spread of Campylobacter at the farm level, few studies support the transmission of Campylobacter spp. from breeder flocks to their offspring. Thus, the present study was carried out to investigate the possibility of vertical transmission. Breeders were monitored from the time of housing day-old chicks, then throughout the laying period (0 to 60 wk) and throughout their progeny (broiler fattening, 1 to 42 d) until slaughter. All samples were analyzed according with official method ISO 10272:2006. Results revealed that on breeder farms, Campylobacter isolation started from wk 16 and reached its peak at wk 26, with 57.0% and 93.2% of positive birds, respectively. After this point, the rate of positive birds decreased slightly to 86.0% at 60 wk. However, in broiler production all day-old chicks were found negative for Campylobacter spp, and the bacteria was first isolated at d 14 of age (5.0%), with a significant increase in detection during the fattening period with 62% of Campylobacter positive animals at the end of the production cycle. Moreover, non-positive sample was determined from environmental sources. These results could be explained because Campylobacter may be in a low concentration or in a non-culturable form, as there were several studies that successfully detected Campylobacter DNA, but failed to culture. This form can survive in the environment and infect successive flocks; consequently, further studies are needed to develop more modern, practical, cost-effective and suitable techniques for routine diagnosis. © 2016 Poultry Science Association Inc.

Identification of quantitative trait loci affecting resistance to gastrointestinal parasites in a double backcross population of Red Maasai and Dorper sheep.

PubMed

Silva, M V B; Sonstegard, T S; Hanotte, O; Mugambi, J M; Garcia, J F; Nagda, S; Gibson, J P; Iraqi, F A; McClintock, A E; Kemp, S J; Boettcher, P J; Malek, M; Van Tassell, C P; Baker, R L

2012-02-01

A genome-wide scan for quantitative trait loci (QTL) affecting gastrointestinal nematode resistance in sheep was completed using a double backcross population derived from Red Maasai and Dorper ewes bred to F(1) rams. This design provided an opportunity to map potentially unique genetic variation associated with a parasite-tolerant breed like Red Maasai, a breed developed to survive East African grazing conditions. Parasite indicator phenotypes (blood packed cell volume - PCV and faecal egg count - FEC) were collected on a weekly basis from 1064 lambs during a single 3-month post-weaning grazing challenge on infected pastures. The averages of last measurements for FEC (AVFEC) and PCV (AVPCV), along with decline in PCV from challenge start to end (PCVD), were used to select lambs (N = 371) for genotyping that represented the tails (10% threshold) of the phenotypic distributions. Marker genotypes for 172 microsatellite loci covering 25 of 26 autosomes (1560.7 cm) were scored and corrected by Genoprob prior to qxpak analysis that included Box-Cox transformed AVFEC and arcsine transformed PCV statistics. Significant QTL for AVFEC and AVPCV were detected on four chromosomes, and this included a novel AVFEC QTL on chromosome 6 that would have remained undetected without Box-Cox transformation methods. The most significant P-values for AVFEC, AVPCV and PCVD overlapped the same marker interval on chromosome 22, suggesting the potential for a single causative mutation, which remains unknown. In all cases, the favourable QTL allele was always contributed from Red Maasai, providing support for the idea that future marker-assisted selection for genetic improvement of production in East Africa will rely on markers in linkage disequilibrium with these QTL. © 2011 The Authors, Animal Genetics © 2011 Stichting International Foundation for Animal Genetics.

Winter-feeding systems for gestating sheep II. Effects on feedlot performance, glucose tolerance, and carcass composition of lamb progeny.

PubMed

Radunz, A E; Fluharty, F L; Susin, I; Felix, T L; Zerby, H N; Loerch, S C

2011-02-01

Mature pregnant crossbred ewes (n = 90) were used in a randomized complete block design experiment and were assigned to 1 of 3 winter-feeding systems differing in primary feed source: haylage (HL), limit-fed corn (CN), or limit-fed dried distillers grains (DDGS). Effects of these winter-feeding strategies on postweaning progeny performance were determined. Lamb progeny (n = 96) were weaned at 61 ± 4 d of age and fed a common high-concentrate diet. Lambs were assigned to feedlot pen (n = 18) based on dam mid-gestation pen. Growth rate, DMI, and ADG were determined for the first 40 d of the finishing period. At 96 ± 4 d of age, 1 wether lamb was randomly selected from each pen (n = 18) for a glucose tolerance test. The experiment was terminated, and lambs were slaughtered individually when they were determined to have achieved 0.6-cm 12th-rib fat thickness. After a 24-h chill, carcass data were collected and a 2.54-cm chop was removed from each lamb from the LM posterior to the 12th rib for ether extract analysis. Additional carcass measurements of bone, muscle, and fat from the shoulder, rack, loin, and leg were collected on 35 carcasses. At weaning, lamb BW was not different among treatments, whereas final BW tended to be greater (P = 0.09) for lambs from ewes fed DDGS and CN during gestation than from those fed HL. Overall lamb growth rate from birth to slaughter was not different among treatments. Lambs from ewes fed DDGS vs. CN or HL tended to have a greater initial insulin response (P = 0.09). Dressing percent was less (P = 0.04) in lambs from ewes fed DDGS, but no difference (P = 0.16) was detected in HCW among treatments. As expected, 12th rib fat thickness was similar among treatments, whereas LM area was largest to smallest (P = 0.05) in lambs from ewes fed CN, HL, and DDGS, respectively. Proportion of internal fat tended to be greatest to smallest (P = 0.06) in lambs from ewes fed DDGS, CN, and HL, respectively. Calculated boneless trimmed retail cuts

Genetic variation in a grapevine progeny (Vitis vinifera L. cvs Grenache×Syrah) reveals inconsistencies between maintenance of daytime leaf water potential and response of transpiration rate under drought

PubMed Central

Coupel-Ledru, Aude; Lebon, Éric; Christophe, Angélique; Doligez, Agnès; Cabrera-Bosquet, Llorenç; Péchier, Philippe; Hamard, Philippe; This, Patrice; Simonneau, Thierry

2014-01-01

In the face of water stress, plants evolved with different abilities to limit the decrease in leaf water potential, notably in the daytime (ΨM). So-called isohydric species efficiently maintain high ΨM, whereas anisohydric species cannot prevent ΨM from dropping as soil water deficit develops. The genetic and physiological origins of these differences in (an)isohydric behaviours remain to be clarified. This is of particular interest within species such as Vitis vinifera L. where continuous variation in the level of isohydry has been observed among cultivars. With this objective, a 2 year experiment was conducted on the pseudo-F1 progeny from a cross between the two widespread cultivars Syrah and Grenache using a phenotyping platform coupled to a controlled-environment chamber. Potted plants of all the progeny were analysed for ΨM, transpiration rate, and soil-to-leaf hydraulic conductance, under both well-watered and water deficit conditions. A high genetic variability was found for all the above traits. Four quantitative trait loci (QTLs) were detected for ΨM under water deficit conditions, and 28 other QTLs were detected for the different traits in either condition. Genetic variation in ΨM maintenance under water deficit weakly correlated with drought-induced reduction in transpiration rate in the progeny, and QTLs for both traits did not completely co-localize. This indicates that genetic variation in the control of ΨM under water deficit was not due simply to variation in transpiration sensitivity to soil drying. Possible origins of the diversity in (an)isohydric behaviours in grapevine are discussed on the basis of concurrent variations in soil-to-leaf hydraulic conductance and stomatal control of transpiration. PMID:25381432

Cellular burdens and biological effects on tissue level caused by inhaled radon progenies.

PubMed

Madas, B G; Balásházy, I; Farkas, Á; Szoke, I

2011-02-01

In the case of radon exposure, the spatial distribution of deposited radioactive particles is highly inhomogeneous in the central airways. The object of this research is to investigate the consequences of this heterogeneity regarding cellular burdens in the bronchial epithelium and to study the possible biological effects at tissue level. Applying computational fluid and particle dynamics techniques, the deposition distribution of inhaled radon daughters has been determined in a bronchial airway model for 23 min of work in the New Mexico uranium mine corresponding to 0.0129 WLM exposure. A numerical epithelium model based on experimental data has been utilised in order to quantify cellular hits and doses. Finally, a carcinogenesis model considering cell death-induced cell-cycle shortening has been applied to assess the biological responses. Present computations reveal that cellular dose may reach 1.5 Gy, which is several orders of magnitude higher than tissue dose. The results are in agreement with the histological finding that the uneven deposition distribution of radon progenies may lead to inhomogeneous spatial distribution of tumours in the bronchial airways. In addition, at the macroscopic level, the relationship between cancer risk and radiation burden seems to be non-linear.

Aggregate formation and suspension culture of human pluripotent stem cells and differentiated progeny.

PubMed

Hookway, Tracy A; Butts, Jessica C; Lee, Emily; Tang, Hengli; McDevitt, Todd C

2016-05-15

Culture of human pluripotent stem cells (hPSC) as in vitro multicellular aggregates has been increasingly used as a method to model early embryonic development. Three-dimensional assemblies of hPSCs facilitate interactions between cells and their microenvironment to promote morphogenesis, analogous to the multicellular organization that accompanies embryogenesis. In this paper, we describe a method for reproducibly generating and maintaining populations of homogeneous three-dimensional hPSC aggregates using forced aggregation and rotary orbital suspension culture. We propose solutions to several challenges associated with the consistent formation and extended culture of cell spheroids generated from hPSCs and their differentiated progeny. Further, we provide examples to demonstrate how aggregation can be used as a tool to select specific subpopulations of cells to create homotypic spheroids, or as a means to introduce multiple cell types to create heterotypic tissue constructs. Finally, we demonstrate that the aggregation and rotary suspension method can be used to support culture and maintenance of hPSC-derived cell populations representing each of the three germ layers, underscoring the utility of this platform for culturing many different cell types. Copyright © 2015 Elsevier Inc. All rights reserved.

Isolation and molecular cytogenetic characterization of a wheat - Leymus mollis double monosomic addition line and its progenies with resistance to stripe rust.

PubMed

Yang, Xiaofei; Li, Xin; Wang, Changyou; Chen, Chunhuan; Tian, Zengrong; Ji, Wanquan

2017-12-01

A common wheat - Leymus mollis (2n = 4x = 28, NsNsXmXm) double monosomic addition line, M11003-4-3-8/13/15 (2n = 44 = 42T.a + L.m2 + L.m3), with stripe rust resistance was developed (where T.a represents Triticum aestivum chromosome, L.m represents L. mollis chromosome, and L.m2/3 represents L. mollis chromosome of homoeologous groups 2 and 3). The progenies of line M11003-4-3-8/13/15 were characterized by cytological observation, specific molecular markers, fluorescence in situ hybridization (FISH), and genomic in situ hybridization (GISH). Among the progenies, there existed five different types (I, II, III, IV, and V) of chromosome constitution, the formulas of which were 2n = 44 = 42T.a + 1L.m2 + 1L.m3, 2n = 43 = 42T.a + 1L.m2, 2n = 43 = 42T.a + 1L.m3, 2n = 42 = 42T.a, and 2n = 44 = 42T.a + 2L.m2, respectively. Field disease screening showed that types I and III showed high resistance to stripe rust, while types II, IV, and V were susceptible. Leymus mollis was almost immune to stripe rust, whereas the wheat parent, cultivar 7182, was susceptible. Therefore, we concluded that the stripe rust resistance originated from L. mollis. These various lines could be further fully exploited as important disease resistance materials to enrich wheat genetic resources.

Destiny of a transgene escape from Brassica napus into Brassica rapa.

PubMed

Lu, M.; Kato, M.; Kakihara, F.

2002-07-01

Transgenic Brassica napus can be easily crossed with wild Brassica rapa. The spread of the transgene to wild species has aroused the general concern about its effect on ecological and agricultural systems. This paper was designated, by means of population genetics, to study the fate of a transgene escape from B. napus to B. rapa. Three models were proposed to survey the change in gene frequency during successive backcross processes by considering selection pressures against aneuploids, against herbicide-susceptible individuals, and by considering A-C intergenomic recombination and the effect of genetic drift. The transmission rate of an A-chromosome gene through an individual to the next generation was 50%, irrespective of the chromosome number; while that of a C-chromosome transgene varied from 8.7% to 39.9%, depending on the chromosome number of the individual used in the backcross. Without spraying herbicide, the frequency of an A-chromosome gene was 50% in the BC(1) generation, and decreased by 50% with the advance of each backcross generation; that of a C-chromosome gene was around 39.9% in BC(1), 7.7% in BC(2), 1.2% in BC(3) and 0.1% in the BC(4) generation. Under the selection pressure against herbicide-susceptible individuals, the frequency of a transgene reached a stable value of about 5.5% within six generations of successive backcrossings. The effect of genetic drift and intergenomic exchange on gene transmission rate was discussed. It is suggested that the transgene integrated on a C-chromosome (or better on a cytoplasm genome) is safer than that on an A-chromosome. The transgenic cultivars should be cultivated rotationally by year(s) with other non-transgenic varieties in order to reduce the transfer of the transgene to wild B. rapa species.

Genetic analysis of post-mating reproductive barriers in hybridizing European Populus species

PubMed Central

Macaya-Sanz, D; Suter, L; Joseph, J; Barbará, T; Alba, N; González-Martínez, S C; Widmer, A; Lexer, C

2011-01-01

Molecular genetic analyses of experimental crosses provide important information on the strength and nature of post-mating barriers to gene exchange between divergent populations, which are topics of great interest to evolutionary geneticists and breeders. Although not a trivial task in long-lived organisms such as trees, experimental interspecific recombinants can sometimes be created through controlled crosses involving natural F1's. Here, we used this approach to understand the genetics of post-mating isolation and barriers to introgression in Populus alba and Populus tremula, two ecologically divergent, hybridizing forest trees. We studied 86 interspecific backcross (BC1) progeny and >350 individuals from natural populations of these species for up to 98 nuclear genetic markers, including microsatellites, indels and single nucleotide polymorphisms, and inferred the origin of the cytoplasm of the cross with plastid DNA. Genetic analysis of the BC1 revealed extensive segregation distortions on six chromosomes, and >90% of these (12 out of 13) favored P. tremula donor alleles in the heterospecific genomic background. Since selection was documented during early diploid stages of the progeny, this surprising result was attributed to epistasis, cyto-nuclear coadaptation, heterozygote advantage at nuclear loci experiencing introgression or a combination of these. Our results indicate that gene flow across ‘porous' species barriers affects these poplars and aspens beyond neutral, Mendelian expectations and suggests the mechanisms responsible. Contrary to expectations, the Populus sex determination region is not protected from introgression. Understanding the population dynamics of the Populus sex determination region will require tests based on natural interspecific hybrid zones. PMID:21587301

Genetic analysis of post-mating reproductive barriers in hybridizing European Populus species.

PubMed

Macaya-Sanz, D; Suter, L; Joseph, J; Barbará, T; Alba, N; González-Martínez, S C; Widmer, A; Lexer, C

2011-10-01

Molecular genetic analyses of experimental crosses provide important information on the strength and nature of post-mating barriers to gene exchange between divergent populations, which are topics of great interest to evolutionary geneticists and breeders. Although not a trivial task in long-lived organisms such as trees, experimental interspecific recombinants can sometimes be created through controlled crosses involving natural F(1)'s. Here, we used this approach to understand the genetics of post-mating isolation and barriers to introgression in Populus alba and Populus tremula, two ecologically divergent, hybridizing forest trees. We studied 86 interspecific backcross (BC(1)) progeny and >350 individuals from natural populations of these species for up to 98 nuclear genetic markers, including microsatellites, indels and single nucleotide polymorphisms, and inferred the origin of the cytoplasm of the cross with plastid DNA. Genetic analysis of the BC(1) revealed extensive segregation distortions on six chromosomes, and >90% of these (12 out of 13) favored P. tremula donor alleles in the heterospecific genomic background. Since selection was documented during early diploid stages of the progeny, this surprising result was attributed to epistasis, cyto-nuclear coadaptation, heterozygote advantage at nuclear loci experiencing introgression or a combination of these. Our results indicate that gene flow across 'porous' species barriers affects these poplars and aspens beyond neutral, Mendelian expectations and suggests the mechanisms responsible. Contrary to expectations, the Populus sex determination region is not protected from introgression. Understanding the population dynamics of the Populus sex determination region will require tests based on natural interspecific hybrid zones.

Misregulation of Gene Expression and Sterility in Interspecies Hybrids: Causal Links and Alternative Hypotheses.

PubMed

Civetta, Alberto

2016-05-01

Understanding the origin of species is of interest to biologist in general and evolutionary biologist in particular. Hybrid male sterility (HMS) has been a focus in studies of speciation because sterility imposes a barrier to free gene flow between organisms, thus effectively isolating them as distinct species. In this review, I focus on the role of differential gene expression in HMS and speciation. Microarray and qPCR assays have established associations between misregulation of gene expression and sterility in hybrids between closely related species. These studies originally proposed disrupted expression of spermatogenesis genes as a causative of sterility. Alternatively, rapid genetic divergence of regulatory elements, particularly as they relate to the male sex (fast-male evolution), can drive the misregulation of sperm developmental genes in the absence of sterility. The use of fertile hybrids (both backcross and F1 progeny) as controls has lent support to this alternative explanation. Differences in gene expression between fertile and sterile hybrids can also be influenced by a pattern of faster evolution of the sex chromosome (fast-X evolution) than autosomes. In particular, it would be desirable to establish whether known X-chromosome sterility factors can act as trans-regulatory drivers of genome-wide patterns of misregulation. Genome-wide expression studies coupled with assays of proxies of sterility in F1 and BC progeny have identified candidate HMS genes but functional assays, and a better phenotypic characterization of sterility phenotypes, are needed to rigorously test how these genes might contribute to HMS.

Transfer of sclerotinia resistance from wild relative of Brassica oleracea into Brassica napus using a hexaploidy step.

PubMed

Mei, Jiaqin; Liu, Yao; Wei, Dayong; Wittkop, Benjamin; Ding, Yijuan; Li, Qinfei; Li, Jiana; Wan, Huafang; Li, Zaiyun; Ge, Xianhong; Frauen, Martin; Snowdon, Rod J; Qian, Wei; Friedt, Wolfgang

2015-04-01

Sclerotinia resistance was transferred into rapeseed from a wild relative of Brassica oleracea (B. incana) using hexaploids derived from crosses between B. incana and rapeseed as a bridge. A high level of resistance against Sclerotinia sclerotiorum has been documented in wild Brassica oleracea, but not in cultivated rapeseed (Brassica napus). To transfer sclerotinia resistance from a wild relative into rapeseed, a strategy was proposed using hexaploids (AACCCC) derived from crosses between the wild B. oleracea-related B. incana genotype 'C01' and the Chinese rapeseed variety 'Zhongshuang 9' as a bridge. Progenies (BC1F1) generated by backcrossing the hexaploid to 'Zhongshuang 9' could be generated with a high crossability (average 18.3 seeds per pod). Seventy-three individuals in BC1F1 were firstly screened for resistance with five molecular markers linked to the major resistance QTL on chromosome C09 in 'C01', and 11 individuals harboring resistance loci were selected to develop vegetative clones. Of these, five exhibited significantly higher resistance than 'Zhongshuang 9' and the most resistant individual was chosen to develop the BC1F2 progeny. Finally, five individual genotypes with nearly twofold higher resistance than 'Zhongshuang 9' were found among 100 BC1F2 individuals by using marker-assisted selection and resistance evaluation. Hereof, one rapeseed-type individual with 38 chromosomes and good self-fertility (15.0 ± 3.56 seeds/pod) was identified. Our results indicate that the proposed strategy is effective for transferring sclerotinia resistance from a wild relative of B. oleracea into rapeseed.

Exploring sheath blight quantitative trait loci in a Lemont/O. meridionalis advanced backcross population

USDA-ARS?s Scientific Manuscript database

Oryza meridionalis is the wild Oryza species endemic to Australia. There are eight AA genome Oryza species, one of which is cultivated rice, O. sativa and O. meridionalis is the most diverged of the eight species. An O. eridionalis (IRGC105608) accession was identified as being moderately resistant...

Opportunism of Conidiobolus obscurus stems from depression of infection in situ to progeny colonies of host alatae as disseminators of the aphid-pathogenic fungus.

PubMed

Zhang, Guo-Zhong; Feng, Ming-Guang; Chen, Chun; Ying, Sheng-Hua

2007-04-01

Conidiobolus (Entomophthorales: Ancylistaceae) includes common aphid pathogens but causes sporadic mycosis worldwide. This epizootiological opportunism was explored herein by examining the potential of mycosis transmission in the progeny colonies of 513 Myzus persicae alates as disseminators of C. obscurus often infecting aphids. The alates exposed to spore showers were flown for 2.05 (0.01-8.95) km on flight mills and then reared individually on cabbage at 20-23 degrees C for 14 day colonization. All truly infected alates were mycosed within 6 days and averagely left 3.9 (0-15) nymphs while those uninfected produced 11.6 (0-35) nymphs during the same period. Secondary and tertiary infections occurred only in 16.2% and 4.8% of the progeny colonies of the mycosed alates respectively, due to c. 60% of the cadavers forming resting spores. Most of the contagious infections appeared on days 4-8 after colonization and no more occurred from day 11 onwards. Trends of colony sizes (last-day averaging 51.5 aphids) and mycosis transmission (sixth-day maximum 6.3%) fit well to logistic (r2 = 0.99) and Gompertz growth models (r2 = 0.91) respectively. The results confirm that the opportunism of C. obscurus stems from depression of contagious infection after dissemination by host alates and suggest that it be overwhelmed by the prevalence of other non-resting fungal species.

Genetic basis of climatic adaptation in scots pine by bayesian quantitative trait locus analysis.

PubMed Central

Hurme, P; Sillanpää, M J; Arjas, E; Repo, T; Savolainen, O

2000-01-01

We examined the genetic basis of large adaptive differences in timing of bud set and frost hardiness between natural populations of Scots pine. As a mapping population, we considered an "open-pollinated backcross" progeny by collecting seeds of a single F(1) tree (cross between trees from southern and northern Finland) growing in southern Finland. Due to the special features of the design (no marker information available on grandparents or the father), we applied a Bayesian quantitative trait locus (QTL) mapping method developed previously for outcrossed offspring. We found four potential QTL for timing of bud set and seven for frost hardiness. Bayesian analyses detected more QTL than ANOVA for frost hardiness, but the opposite was true for bud set. These QTL included alleles with rather large effects, and additionally smaller QTL were supported. The largest QTL for bud set date accounted for about a fourth of the mean difference between populations. Thus, natural selection during adaptation has resulted in selection of at least some alleles of rather large effect. PMID:11063704

Mapping of the X-linked cataract (Xcat) mutation, the gene implicated in the Nance Horan syndrome, on the mouse X chromosome.

PubMed

Stambolian, D; Favor, J; Silvers, W; Avner, P; Chapman, V; Zhou, E

1994-07-15

The Xcat mutation in the mouse, an X-linked inherited disorder, is characterized by the congenital onset of cataracts. The cataracts have morphologies similar to those of cataracts found in the human Nance Horan (X-linked cataract dental) syndrome, suggesting that Xcat is an animal model for Nance Horan. The Xcat mutation provides an opportunity to investigate, at the molecular level, the pathogenesis of cataract. As a first step to cloning the Xcat gene, we report the localization of the Xcat mutation with respect to known molecular markers on the mouse X chromosome. Back-cross progeny carrying the Xcat mutation were obtained from an interspecific cross. Genomic DNA from each mouse was subjected to Southern and PCR analysis to identify restriction fragment length polymorphisms and simple sequence length polymorphisms, respectively. Our results refine the location of Xcat to a 2-cM region, eliminate several genes from consideration as the Xcat mutation, identify molecular probes tightly linked with Xcat, and suggest candidate genes responsible for the Xcat phenotype.

Extrachromosomal Inheritance of Carbon Dioxide Sensitivity in the Mosquito CULEX QUINQUEFASCIATUS

PubMed Central

Shroyer, Donald A.; Rosen, Leon

1983-01-01

Mosquitoes from a laboratory colony of Culex quinquefasciatus from Matsu Island, China, develop irreversible paralytic symptoms after exposure to carbon dioxide at 1°. This CO2 sensitivity is caused by an inherited infectious agent, probably a virus. Crossing studies between CO2-sensitive and -resistant mosquitoes showed that the sensitivity trait is inherited extrachromosomally in a fashion strictly analogous to the hereditary transmission of sigma virus in Drosophila melanogaster. Sensitivity could be maintained through maternal transmission alone, despite nine generations of backcrossing of "stabilized" CO2-sensitive females to males from a resistant strain. CO2-sensitive males crossed to resistant females transmitted sensitivity to a portion of their F 1 progeny, and only the female F1 sensitives were capable of further hereditary transmission.—Matsu, or a very similar hereditary infectious agent, is common in natural populations of Cx. quinquefasciatus on Oahu, Hawaii. Fifty-nine percent of the families reared from field-collected egg rafts contained CO2-sensitive mosquitoes, and some families contained only sensitive mosquitoes. PMID:6413297

Genomewide Scan Reveals Amplification of mdr1 as a Common Denominator of Resistance to Mefloquine, Lumefantrine, and Artemisinin in Plasmodium chabaudi Malaria Parasites▿†‡

PubMed Central

Borges, Sofia; Cravo, Pedro; Creasey, Alison; Fawcett, Richard; Modrzynska, Katarzyna; Rodrigues, Louise; Martinelli, Axel; Hunt, Paul

2011-01-01

Multidrug-resistant Plasmodium falciparum malaria parasites pose a threat to effective drug control, even to artemisinin-based combination therapies (ACTs). Here we used linkage group selection and Solexa whole-genome resequencing to investigate the genetic basis of resistance to component drugs of ACTs. Using the rodent malaria parasite P. chabaudi, we analyzed the uncloned progeny of a genetic backcross between the mefloquine-, lumefantrine-, and artemisinin-resistant mutant AS-15MF and a genetically distinct sensitive clone, AJ, following drug treatment. Genomewide scans of selection showed that parasites surviving each drug treatment bore a duplication of a segment of chromosome 12 (translocated to chromosome 04) present in AS-15MF. Whole-genome resequencing identified the size of the duplicated segment and its position on chromosome 4. The duplicated fragment extends for ∼393 kbp and contains over 100 genes, including mdr1, encoding the multidrug resistance P-glycoprotein homologue 1. We therefore show that resistance to chemically distinct components of ACTs is mediated by the same genetic mutation, highlighting a possible limitation of these therapies. PMID:21709099

Modulatory Role of Sensory Innervation on Hair Follicle Stem Cell Progeny during Wound Healing of the Rat Skin

PubMed Central

Martínez-Martínez, Eduardo; Galván-Hernández, Claudio I.; Toscano-Márquez, Brenda; Gutiérrez-Ospina, Gabriel

2012-01-01

Background The bulge region of the hair follicle contains resident epithelial stem cells (SCs) that are activated and mobilized during hair growth and after epidermal wounding. However, little is known about the signals that modulate these processes. Clinical and experimental observations show that a reduced supply of sensory innervation is associated with delayed wound healing. Since axon terminals of sensory neurons are among the components of the bulge SC niche, we investigated whether these neurons are involved in the activation and mobilization of the hair stem cells during wound healing. Methodology/Principal Findings We used neonatal capsaicin treatment to reduce sensory terminals in the rat skin and performed morphometric analyses using design-based stereological methods. Epithelial proliferation was analyzed by quantifying the number of bromodeoxyuridine-labeled (BrdU+) nuclei in the epidermis and hair follicles. After wounding, the epidermis of capsaicin-treated rats presented fewer BrdU+ nuclei than in control rats. To assess SC progeny migration, we employed a double labeling protocol with iododeoxyuridine and chlorodeoxyuridine (IdU+/CldU+). The proportion of double-labeled cells was similar in the hair follicles of both groups at 32 h postwounding. IdU+/CldU+ cell proportion increased in the epidermis of control rats and decreased in treated rats at 61 h postwounding. The epidermal volume immunostained for keratin 6 was greater in treated rats at 61 h. Confocal microscopy analysis revealed that substance P (SP) and calcitonin gene-related peptide (CGRP) receptor immunoreactivity were both present in CD34+ and BrdU-retaining cells of the hair follicles. Conclusions/Significance Our results suggest that capsaicin denervation impairs SC progeny egress from the hair follicles, a circumstance associated with a greater epidermal activation. Altogether, these phenomena would explain the longer times for healing in denervated skin. Thus, sensory innervation

Proposal of a super trait for the optimum selection of popcorn progenies based on path analysis.

PubMed

do Amaral Júnior, A T; Dos Santos, A; Gerhardt, I F S; Kurosawa, R N F; Moreira, N F; Pereira, M G; de A Gravina, G; de L Silva, F H

2016-12-19

A challenge faced by popcorn breeding programs is the existence of a negative correlation between the two main traits, popping expansion and yield, which hinders simultaneous gains. The objective of this study was to investigate the use of a new variable or super trait, which favors the reliable selection of superior progenies. The super trait 'expanded popcorn volume per hectare' was introduced in the evaluation of 200 full-sib families of the eighth recurrent intrapopulation selection cycle, which were arranged in randomized blocks with three replicates in two environments. Although the inability to obtain simultaneous gains through selection via popping expansion or yield was confirmed, the super trait was positively associated with both yield and popping expansion, allowing simultaneous gains via indirect selection using 'expanded popcorn volume per hectare' as the main trait. This approach is recommended because this super trait can be used in breeding programs to optimize selective gains for the crop.

A Hyaluronan-Based Injectable Hydrogel Improves the Survival and Integration of Stem Cell Progeny following Transplantation.

PubMed

Ballios, Brian G; Cooke, Michael J; Donaldson, Laura; Coles, Brenda L K; Morshead, Cindi M; van der Kooy, Derek; Shoichet, Molly S

2015-06-09

The utility of stem cells and their progeny in adult transplantation models has been limited by poor survival and integration. We designed an injectable and bioresorbable hydrogel blend of hyaluronan and methylcellulose (HAMC) and tested it with two cell types in two animal models, thereby gaining an understanding of its general applicability for enhanced cell distribution, survival, integration, and functional repair relative to conventional cell delivery in saline. HAMC improves cell survival and integration of retinal stem cell (RSC)-derived rods in the retina. The pro-survival mechanism of HAMC is ascribed to the interaction of the CD44 receptor with HA. Transient disruption of the retinal outer limiting membrane, combined with HAMC delivery, results in significantly improved rod survival and visual function. HAMC also improves the distribution, viability, and functional repair of neural stem and progenitor cells (NSCs). The HAMC delivery system improves cell transplantation efficacy in two CNS models, suggesting broad applicability. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Evaluation of Antioxidant Compounds and Total Sugar Content in a Nectarine [Prunus persica (L.) Batsch] Progeny

PubMed Central

Abidi, Walid; Jiménez, Sergio; Moreno, María Ángeles; Gogorcena, Yolanda

2011-01-01

Epidemiological studies suggest that consumption of fruit rich in phenolic compounds is associated with health-protective effects due to their antioxidant properties. For these reasons quality evaluation has become an important issue in fruit industry and in breeding programs. Phytochemical traits such as total phenolics, flavonoids, anthocyanins, L-ascorbic acid, sugar content and relative antioxidant capacity (RAC) were analyzed over four years in flesh fruit of an F1 population “Venus” × “Big Top” nectarines. Other traits such as harvesting date, yield, fruit weight, firmness, soluble solids concentration (SSC), pH, titratable acidity (TA) and ripening index (RI) were also determined in the progeny. Results showed high variability among genotypes for all analyzed traits. Total phenolics and flavonoids showed significant positive correlations with RAC implying that both are important antioxidant bioactive compounds in peaches. We found genotypes with enhanced antioxidant capacity and a better performance than progenitors, and in consequence the best marketability. PMID:22072927

Genetic basis of HDL variation in 129/SvImJ and C57BL/6J mice: importance of testing candidate genes in targeted mutant mice*s⃞

PubMed Central

Su, Zhiguang; Wang, Xiaosong; Tsaih, Shirng-Wern; Zhang, Aihong; Cox, Allison; Sheehan, Susan; Paigen, Beverly

2009-01-01

To evaluate the effect of genetic background on high-density lipoprotein cholesterol (HDL) levels in Soat1−/− mice, we backcrossed sterol O-acyltransferase 1 (Soat1)−/− mice, originally reported to have elevated HDL levels, to C57BL/6 mice and constructed a congenic strain with only a small region (3.3Mb) of 129 alleles, specifically excluding the nearby apolipoprotein A-II (Apoa2) gene from 129. HDL levels in these Soat1−/− mice were no different from C57BL/6, indicating that the passenger gene Apoa2 caused the previously reported elevation of HDL in these Soat1−/− mice. Because many knockouts are made in strain 129 and then subsequently backcrossed into C57BL/6, it is important to identify quantitative trait loci (QTL) that differ between 129 and C57BL/6 so that one can guard against effects ascribed to a knockout but really caused by a passenger gene from 129. To provide such data, we generated 528 F2 progeny from an intercross of 129S1/SvImJ and C57BL/6 and measured HDL concentrations in F2 animals first fed chow and then atherogenic diet. A genome wide scan using 508 single-nucleotide polymorphisms (SNPs) identified 19 QTL, 2 of which were male specific and 2 were female specific. Using comparative genomics and haplotype analysis, we narrowed QTL on chromosomes 3, 5, 8, 17, and 18 to 0.5, 6.3, 2.6, 1.1, and 0.6 Mb, respectively. These data will serve as a reference for any effort to test the impact of candidate genes on HDL using a knockout strategy. PMID:18772481

Quantitative trait loci analysis of Verticillium wilt resistance in interspecific backcross populations of Gossypium hirsutum × Gossypium barbadense.

PubMed

Shi, Yuzhen; Zhang, Baocai; Liu, Aiying; Li, Wentan; Li, Junwen; Lu, Quanwei; Zhang, Zhen; Li, Shaoqi; Gong, Wankui; Shang, Haihong; Gong, Juwu; Chen, Tingting; Ge, Qun; Wang, Tao; Zhu, Heqin; Liu, Zhi; Yuan, Youlu

2016-11-05

Verticillium wilt (VW) caused by Verticillium dahliae (Kleb) is one of the most destructive diseases of cotton. The identification of highly resistant QTLs or genes in the whole cotton genome is quite important for developing a VW-resistant variety and for further molecular design breeding. In the present study, BC 1 F 1 , BC 1 S 1 , and BC 2 F 1 populations derived from an interspecific backcross between the highly resistant line Hai1 (Gossypium barbadense L.) and the susceptible variety CCRI36 (G. hirsutum L.) as the recurrent parent were constructed. Quantitative trait loci (QTL) related to VW resistance were detected in the whole cotton genome using a high-density simple sequence repeat (SSR) genetic linkage map from the BC 1 F 1 population, with 2292 loci covering 5115.16 centiMorgan (cM) of the cotton (AD) genome, and the data concerning VW resistance that were obtained from four dates of BC 2 F 1 in the artificial disease nursery and one date of BC 1 S 1 and BC 2 F 1 in the field. A total of 48 QTLs for VW resistance were identified, and 37 of these QTLs had positive additive effects, which indicated that the G. barbadense alleles increased resistance to VW and decreased the disease index (DI) by about 2.2-10.7. These QTLs were located on 19 chromosomes, in which 33 in the A subgenome and 15 QTLs in the D subgenome. The 6 QTLs were found to be stable. The 6 QTLs were consistent with those identified previously, and another 42 were new, unreported QTLs, of which 31 QTLs were from G. barbadense. By meta-analysis, 17 QTL hotspot regions were identified and 10 of them were new, unreported hotspot regions. 29 QTLs in this paper were in 12 hotspot regions and were all from G. barbadense. These stable or consensus QTL regions warrant further investigation to better understand the genetics and molecular mechanisms underlying VW resistance. This study provides useful information for further comparative analysis and marker-assisted selection in the breeding of disease

Supplementation of organic and inorganic selenium to late gestation and early lactation beef cows effect on progeny feedlot performance and carcass characteristics.

PubMed

Muegge, C R; Brennan, K M; Schoonmaker, J P

2017-03-01

Angus × Simmental cows ( = 48, BW = 594 kg, BCS = 5.26, age = 2.7) pregnant with male fetuses were used to determine the effect of selenium source during the last 80 d of gestation and first 108 d of lactation on progeny feedlot performance. At 203 d of gestation, cows were blocked by BW, breed composition, and calf sire and randomly allotted to 1 of 3 treatments: no supplemental Se, 3 mg/d inorganic Se (sodium selenite), and 3 mg/d organic Se (Sel-plex). Maternal diets were formulated to contain 10.4% CP and 0.90 Mcal/kg NE during gestation and 12.1% CP and 1.01 Mcal/kg NE during lactation. Basal diets contained 0.07 and 0.11 mg/kg Se for gestation and lactation diets, respectively. Diets were fed daily as a total mixed ration, and no additional Se, 3 mg/d Se as sodium selenite, or 3 mg/d Se as Sel-Plex were top-dressed daily. Treatment diets were fed through 108 d postpartum (DPP). At 108 DPP cow-calf pairs were commingled until weaning at 210 DPP. At 28 d postweaning, steers ( = 47, BW = 301 kg) were placed in individual pens and fed a diet formulated to provide 13.9% CP and 1.24 Mcal/kg NE. No supplemental Se was fed; however, basal Se concentration was 0.10 mg/kg. The diet was delivered as a total mixed ration once daily. Steers were slaughtered at a target BW of 625 kg. Steers from cows supplemented with organic Se tended to enter the feedlot heavier ( = 0.06) than steers from cows supplemented with inorganic Se. There was no difference in ADG among treatments ( ≥ 0.73), but steers from organic Se cows tended to spend fewer days on feed compared to steers from inorganic Se cows ( = 0.09). Steers from organic Se cows had a greater overall DMI compared to steers from inorganic Se cows ( = 0.04), but there was no difference in overall G:F ( = 0.49). Dressing percentage was greater for steers from cows fed no Se compared with steers from cows fed either inorganic or organic Se ( = 0.03). Maternal Se source had no effect on HCW, back fat, percentage KPH, LM

The effect of copper-amended fertiliser and copper oxide wire particles on the copper status of farmed red deer (Cervus elaphus) and their progeny.

PubMed

Grace, N D; Wilson, P R; Quinn, A K

2005-02-01

To determine changes in serum and liver copper concentrations in postnatal, weaner, yearling, and mature deer after grazing pasture topdressed with copper (Cu) at two rates of application of copper sulphate (CuSO4(.)5H2O), and following oral administration of copper oxide (CuO) wire particles to some of the deer. In mid-March 2000 (Year 1), 1.1-ha paddocks (two/treatment) of ryegrass/white clover pasture received either 0 (Control), 6 (Low) or 12 (High) kg CuSO4(.)5H2O /ha applied with 250 kg potash superphosphate/ha. They were grazed by 4-month-old red deer hinds (n=11/treatment) from mid-April 2000 until early March 2001. In mid-March 2001 (Year 2), the pastures were topdressed again as for Year 1, and the original hinds, now yearlings which had grazed as a single group between studies, were returned to their respective treatments in mid-April 2001 and remained on the trial until mid-March 2002. They were mated during April/May. The pastures were also grazed by pregnant mature hinds (n=8/treatment) from mid-May 2001. As the Cu status (i.e. liver Cu concentration) of the yearling hinds on the pasture treated with 6 kg CuSO4(.)5H2O/ha was not significantly different from the untreated animals, in late July 2001 the yearling and mature deer on this treatment were treated orally with 10 g CuO wire particles. The mature hinds calved in November and the yearling hinds in December. Pasture samples were collected at about monthly intervals to determine concentrations of Cu and other minerals. In Year 1, liver biopsies and blood samples were collected at 4-6-weekly intervals for determination of Cu concentrations. In Year 2, samples were collected similarly at 6-12-weekly intervals. Liver biopsies and blood were also collected from progeny, along with milk from their dams. Liveweights were determined at 3-7-monthly intervals, as well as data on calving/mortality rates. Pasture Cu concentrations before the application of CuSO4(.)5H2O were 6-9 mg Cu/kg dry matter (DM) and

Pregnancy alters the circulating B cell compartment in atopic asthmatic women, and transitional B cells are positively associated with the development of allergy manifestations in their progeny.

PubMed

Martins, Catarina; Lima, Jorge; Nunes, Glória; Borrego, Luís Miguel

2016-12-01

Maternal atopy is a risk factor for allergy. B cells are poorly studied in reproduction and atopy. We aimed to assess how pregnancy affects B cells in atopic women and whether B cells relate to allergic manifestations in offspring. Women with and without atopic asthma, pregnant and non-pregnant were enrolled for the study, and circulating B cells were evaluated by flow cytometry, using CD19, CD27, CD38, IgD, and IgM. Compared to healthy non-pregnant, atopic asthmatic non-pregnant (ANP) women presented increased B cell counts, enlarged memory subsets, less transitional cells, and plasmablasts. Atopic asthmatic pregnant (AP) and healthy pregnant (HP) women showed similarities: reduced B cell counts and percentages, fewer memory cells, especially switched, and higher plasmablast percentages. Transitional B cell percentages were increased in AP women with allergic manifestations in their progeny. Atopic asthmatic non-pregnant women have a distinctive B cell compartment. B cells change in pregnancy, similarly in AP and HP women. The recognition that AP women with allergy in their progeny have a typical immune profile may help, in the future, the adoption of preventive measures to avoid the manifestation of allergic diseases in their newborns. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The NS2 proteins of parvovirus minute virus of mice are required for efficient nuclear egress of progeny virions in mouse cells.

PubMed

Eichwald, Virginie; Daeffler, Laurent; Klein, Michèle; Rommelaere, Jean; Salomé, Nathalie

2002-10-01

The small nonstructural NS2 proteins of parvovirus minute virus of mice (MVMp) were previously shown to interact with the nuclear export receptor Crm1. We report here the analysis of two MVM mutant genomic clones generating NS2 proteins that are unable to interact with Crm1 as a result of amino acid substitutions within their nuclear export signal (NES) sequences. Upon transfection of human and mouse cells, the MVM-NES21 and MVM-NES22 mutant genomic clones were proficient in synthesis of the four virus-encoded proteins. While the MVM-NES22 clone was further able to produce infectious mutant virions, no virus could be recovered from cells transfected with the MVM-NES21 clone. Whereas the defect of MVM-NES21 appeared to be complex, the phenotype of MVM-NES22 could be traced back to a novel distinct NS2 function. Infection of mouse cells with the MVM-NES22 mutant led to stronger nuclear retention not only of the NS2 proteins but also of infectious progeny MVM particles. This nuclear sequestration correlated with a severe delay in the release of mutant virions in the medium and with prolonged survival of the infected cell populations compared with wild-type virus-treated cultures. This defect could explain, at least in part, the small size of the plaques generated by the MVM-NES22 mutant when assayed on mouse indicator cells. Altogether, our data indicate that the interaction of MVMp NS2 proteins with the nuclear export receptor Crm1 plays a critical role at a late stage of the parvovirus life cycle involved in release of progeny viruses.

The NS2 Proteins of Parvovirus Minute Virus of Mice Are Required for Efficient Nuclear Egress of Progeny Virions in Mouse Cells

PubMed Central

Eichwald, Virginie; Daeffler, Laurent; Klein, Michèle; Rommelaere, Jean; Salomé, Nathalie

2002-01-01

The small nonstructural NS2 proteins of parvovirus minute virus of mice (MVMp) were previously shown to interact with the nuclear export receptor Crm1. We report here the analysis of two MVM mutant genomic clones generating NS2 proteins that are unable to interact with Crm1 as a result of amino acid substitutions within their nuclear export signal (NES) sequences. Upon transfection of human and mouse cells, the MVM-NES21 and MVM-NES22 mutant genomic clones were proficient in synthesis of the four virus-encoded proteins. While the MVM-NES22 clone was further able to produce infectious mutant virions, no virus could be recovered from cells transfected with the MVM-NES21 clone. Whereas the defect of MVM-NES21 appeared to be complex, the phenotype of MVM-NES22 could be traced back to a novel distinct NS2 function. Infection of mouse cells with the MVM-NES22 mutant led to stronger nuclear retention not only of the NS2 proteins but also of infectious progeny MVM particles. This nuclear sequestration correlated with a severe delay in the release of mutant virions in the medium and with prolonged survival of the infected cell populations compared with wild-type virus-treated cultures. This defect could explain, at least in part, the small size of the plaques generated by the MVM-NES22 mutant when assayed on mouse indicator cells. Altogether, our data indicate that the interaction of MVMp NS2 proteins with the nuclear export receptor Crm1 plays a critical role at a late stage of the parvovirus life cycle involved in release of progeny viruses. PMID:12239307

Inheritance and effectiveness of two transgenes determining PVY resistance in progeny from crossing independently transformed tobacco lines.

PubMed

Czubacka, Anna; Sacco, Ermanno; Olszak-Przybyś, Hanna; Doroszewska, Teresa

2017-05-01

Genetic transformation of plants allows us to obtain improved genotypes enriched with the desired traits. However, if transgenic lines were to be used in breeding programs the stability of inserted transgenes is essential. In the present study, we followed the inheritance of transgenes in hybrids originated from crossing two transgenic tobacco lines resistant to Potato virus Y (PVY): MN 944 LMV with the transgene containing Lettuce mosaic virus coat protein gene (LMV CP) and AC Gayed ROKY2 with PVY replicase gene (ROKY2). Progeny populations generated by successive self-pollination were analyzed with respect to the transgene segregation ratio and resistance to Potato virus Y in tests carried out under greenhouse conditions. The presence of the virus in inoculated plants was detected by DAS-ELISA method. The results demonstrated the Mendelian fashion of inheritance of transgenes which were segregated independently and stably. As a result, we obtained T 4 generation of hybrid with both transgenes stacked and which was highly resistant to PVY.

Gestational exposure to diethylstilbestrol alters cardiac structure/function, protein expression and DNA methylation in adult male mice progeny

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

Haddad, Rami, E-mail: rami.haddad@mail.mcgill.ca; Division of Experimental Medicine, Department of Medicine, McGill University, 850 Sherbrooke Street, Montréal, Québec, Canada H3A 1A2; Kasneci, Amanda, E-mail: amanda.kasneci@mail.mcgill.ca

2013-01-01

Pregnant women, and thus their fetuses, are exposed to many endocrine disruptor compounds (EDCs). Fetal cardiomyocytes express sex hormone receptors making them potentially susceptible to re-programming by estrogenizing EDCs. Diethylstilbestrol (DES) is a proto-typical, non-steroidal estrogen. We hypothesized that changes in adult cardiac structure/function after gestational exposure to the test compound DES would be a proof in principle for the possibility of estrogenizing environmental EDCs to also alter the fetal heart. Vehicle (peanut oil) or DES (0.1, 1.0 and 10.0 μg/kg/da.) was orally delivered to pregnant C57bl/6n dams on gestation days 11.5–14.5. At 3 months, male progeny were left sedentarymore » or were swim trained for 4 weeks. Echocardiography of isoflurane anesthetized mice revealed similar cardiac structure/function in all sedentary mice, but evidence of systolic dysfunction and increased diastolic relaxation after swim training at higher DES doses. The calcium homeostasis proteins, SERCA2a, phospholamban, phospho-serine 16 phospholamban and calsequestrin 2, are important for cardiac contraction and relaxation. Immunoblot analyses of ventricle homogenates showed increased expression of SERCA2a and calsequestrin 2 in DES mice and greater molecular remodeling of these proteins and phospho-serine 16 phospholamban in swim trained DES mice. DES increased cardiac DNA methyltransferase 3a expression and DNA methylation in the CpG island within the calsequestrin 2 promoter in heart. Thus, gestational DES epigenetically altered ventricular DNA, altered cardiac function and expression, and reduced the ability of adult progeny to cardiac remodel when physically challenged. We conclude that gestational exposure to estrogenizing EDCs may impact cardiac structure/function in adult males. -- Highlights: ► Gestational DES changes cardiac SERCA2a and CASQ2 expression. ► Echocardiography identified systolic dysfunction and increased diastolic relaxation. �

Comparison of efficiency of distance measurement methodologies in mango (Mangifera indica) progenies based on physicochemical descriptors.

PubMed

Alves, E O S; Cerqueira-Silva, C B M; Souza, A M; Santos, C A F; Lima Neto, F P; Corrêa, R X

2012-03-14

We investigated seven distance measures in a set of observations of physicochemical variables of mango (Mangifera indica) submitted to multivariate analyses (distance, projection and grouping). To estimate the distance measurements, five mango progeny (total of 25 genotypes) were analyzed, using six fruit physicochemical descriptors (fruit weight, equatorial diameter, longitudinal diameter, total soluble solids in °Brix, total titratable acidity, and pH). The distance measurements were compared by the Spearman correlation test, projection in two-dimensional space and grouping efficiency. The Spearman correlation coefficients between the seven distance measurements were, except for the Mahalanobis' generalized distance (0.41 ≤ rs ≤ 0.63), high and significant (rs ≥ 0.91; P < 0.001). Regardless of the origin of the distance matrix, the unweighted pair group method with arithmetic mean grouping method proved to be the most adequate. The various distance measurements and grouping methods gave different values for distortion (-116.5 ≤ D ≤ 74.5), cophenetic correlation (0.26 ≤ rc ≤ 0.76) and stress (-1.9 ≤ S ≤ 58.9). Choice of distance measurement and analysis methods influence the.

Inheritance and stability of mevinphos-resistance in Plutella xylostella (L.), with special reference to mutations of acetylcholinesterase 1.

PubMed

Lin, Chia-Li; Yeh, Shih-Chia; Feng, Hai-Tung; Dai, Shu-Mei

2017-09-01

Diamondback moth (Plutella xylostella L.) causes enormous damage on cruciferous vegetables and can rapidly develop resistance to all kinds of insecticides. To effectively manage the insecticide resistance of P. xylostella, an understanding of its inheritance and stability is essential. Here we investigated the phenotypic and genotypic basis of mevinphos resistance by crossing two genetically pure lines of P. xylostella, an SH ggt wild-type strain and an SHM TCN resistant strain carrying 892T/T, 971C/C, and 1156T/G (TCN) mutations of the acetylcholinesterase 1 gene (Pxace1). Similar median lethal concentrations and degrees of dominance in the reciprocal cross progeny, and no plateau on the log concentration-probit line of F1 backcross and self-cross progeny, suggest that the mevinphos-resistance in P. xylostella is inherited as an autosomal and incomplete dominant trait governed by more than one gene. In the absence of mevinphos exposure, the resistance ratio and Pxace1 mutation frequency declined concomitantly in the SHM TCN strain. After 20-generation relaxation, the mevinphos resistance decreased from 52- to 6-fold and the Pxace1 mutation frequency of the TCN haplotype pair decreased from 100% to 0%. A good correlation was found between the resistance ratio and TCN frequency within the range of 12.5- to 25-fold resistance. Since there was no TCN haplotype pair detected below a resistance level of 12.5-fold, we speculate that resistance mechanisms other than target site insensitivity may exist. These observations are important for the prediction and management of mevinphos and related organophosphate resistance in field populations of P. xylostella. Copyright © 2016. Published by Elsevier Inc.

Length of paternal lifespan is manifested in the DNA methylome of their nonagenarian progeny

PubMed Central

Marttila, Saara; Kananen, Laura; Jylhävä, Juulia; Nevalainen, Tapio; Hervonen, Antti; Jylhä, Marja; Hurme, Mikko

2015-01-01

The heritability of lifespan is 20-30%, but only a few genes associated with longevity have been identified. To explain this discrepancy, the inheritance of epigenetic features, such as DNA methylation, have been proposed to contribute to the heritability of lifespan. We investigated whether parental lifespan is associated with DNA methylation profile in nonagenarians. A regression model, adjusted for differences in blood cell proportions, identified 659 CpG sites where the level of methylation was associated with paternal lifespan. However, no association was observed between maternal lifespan and DNA methylation. The 659 CpG sites associated with paternal lifespan were enriched outside of CpG islands and were located in genes associated with development and morphogenesis, as well as cell signaling. The largest difference in the level of methylation between the progeny of the shortest-lived and longest-lived fathers was identified for CpG sites mapping to CXXC5. In addition, the level of methylation in three Notch-genes (NOTCH1, NOTCH3 and NOTCH4) was also associated with paternal lifespan. There are implications for the inheritance of acquired traits via epigenetic mechanisms in mammals. Here we describe DNA methylation features that are associated with paternal lifespan, and we speculate that the identified CpG sites may represent intergenerational epigenetic inheritance. PMID:26436701

Strategies in identifying individuals in a segregant population of common bean and implications of genotype x environment interaction in the success of selection.

PubMed

Mendes, M P; Ramalho, M A P; Abreu, A F B

2012-04-10

The objective of this study was to compare the BLUP selection method with different selection strategies in F(2:4) and assess the efficiency of this method on the early choice of the best common bean (Phaseolus vulgaris) lines. Fifty-one F(2:4) progenies were produced from a cross between the CVIII8511 x RP-26 lines. A randomized block design was used with 20 replications and one-plant field plots. Character data on plant architecture and grain yield were obtained and then the sum of the standardized variables was estimated for simultaneous selection of both traits. Analysis was carried out by mixed models (BLUP) and the least squares method to compare different selection strategies, like mass selection, stratified mass selection and between and within progeny selection. The progenies selected by BLUP were assessed in advanced generations, always selecting the greatest and smallest sum of the standardized variables. Analyses by the least squares method and BLUP procedure ranked the progenies in the same way. The coincidence of the individuals identified by BLUP and between and within progeny selection was high and of the greatest magnitude when BLUP was compared with mass selection. Although BLUP is the best estimator of genotypic value, its efficiency in the response to long term selection is not different from any of the other methods, because it is also unable to predict the future effect of the progenies x environments interaction. It was inferred that selection success will always depend on the most accurate possible progeny assessment and using alternatives to reduce the progenies x environments interaction effect.

Genetic progress estimation strategy for upright common bean plants using recurrent selection.

PubMed

Pereira, L A; Abreu, A F B; Júnior, I C Vieira; Pires, L P M; Ramalho, M A P

2017-03-22

Common bean producers in Brazil tend to grow plants as upright as possible. Because the control of this trait involves a large number of genes, recurrent selection (RS) is the best approach for successful plant improvement. Because plant architecture (PA) is evaluated using scores and usually has high heritability, RS for PA is performed through visual selection in generation S 0 . The aim of the present study was to evaluate selection progress and investigate whether this progress varies with the number of selected progenies or the generation evaluated. In addition, the effect of RS for the upright (PA) trait on progeny grain yield (GY) was investigated. Data of progenies S 0:3 and S 0:4 of the fifth, eighth, and twelfth cycles were used. A combined analysis of variance was performed using the adjusted means of the 47 best progenies from each generation and cycle, using two control cultivars as reference. A joint analysis of the two generations used during the evaluation of progenies for the different cycles was also performed. The genetic progress (GP) was estimated by fitting a linear regression equation to the relationship between the adjusted mean of each cycle and the number of cycles. We found that RS was efficient and the estimated GP of the evaluated progenies was 4.5%. Based on the GY heritability estimates, in more advanced generation selection for GY can be successfully performed on progenies. Thus, the selection already done for PA in F 2 could be associated to the most productive progenies.

MUC4 down-regulation reverses chemoresistance of pancreatic cancer stem/progenitor cells and their progenies.

PubMed

Mimeault, Murielle; Johansson, Sonny L; Senapati, Shantibhusan; Momi, Navneet; Chakraborty, Subhankar; Batra, Surinder K

2010-09-01

The present study was undertaken to estimate the therapeutic benefit to down-regulate the MUC4 mucin for reversing chemoresistance of pancreatic cancer (PC) stem/progenitor cells and their progenies. The results have revealed that MUC4 mucin is overexpressed in CD133(+) and CD133(-) pancreatic cells (PCs) detected in patient's adenocarcinoma tissues while no significant expression was seen in normal pancreatic tissues. The gain- and loss-of-function analyses have indicated that the overexpression of MUC4 in PC lines is associated with a higher resistance to the anti-proliferative, anti-invasive and apoptotic effects induced by gemcitabine. Importantly, the treatment of the MUC4-overexpressing CD18/HPAF-Src cells with gemcitabine resulted in an enrichment of the side population (SP) cells expressing CD133 while the total PC cells including non-SP cells detected in MUC4 knockdown CD18/HPAF-shMUC4 cells were responsive to the cytotoxic effects induced by gemcitabine. These data suggest that the MUC4 down-regulation may constitute a potential therapeutic strategy for improving the efficacy of gemcitabine to eradicate the total PC cell mass, and thereby preventing disease relapse. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

Feeding dried distillers grains with solubles to lactating beef cows: impact of excess protein and fat on cow performance, milk production and pre-weaning progeny growth.

PubMed

Shee, C N; Lemenager, R P; Schoonmaker, J P

2016-01-01

Multiparous Angus×Simmental cows (n=54, 5.22±2.51 years) with male progeny were fed one of two diets supplemented with either dried distillers grains with solubles (DDGS) or soybean meal (CON), from calving until day 129 postpartum (PP) to determine effects of excess protein and fat on cow performance, milk composition and calf growth. Diets were formulated to be isocaloric and consisted of rye hay and DDGS (19.4% CP; 8.76% fat), or corn silage, rye hay and soybean meal (11.7% CP; 2.06% fat). Cow-calf pairs were allotted by cow and calf age, BW and breed. Cow BW and body condition score (BCS; P⩾0.13) were similar throughout the experiment. A weigh-suckle-weigh was performed on day 64 and day 110±10 PP to determine milk production. Milk was collected on day 68 and day 116±10 PP for analysis of milk components. Milk production was unaffected (P⩾0.75) by dietary treatments. Milk urea nitrogen was increased at both time points in DDGS compared with CON cows (P<0.01). Protein was decreased (P=0.01) and fat was increased (P=0.01) in milk from DDGS compared with CON cows on day 68 PP. Compared to CON, DDGS decreased medium chain FA (P<0.01) and increased long chain FA (P<0.01) at both time points. Saturated FA content of milk was decreased (P<0.01) at both time-points in DDGS compared with CON cows, which resulted in an increase (P<0.01) in monounsaturated and polyunsaturated FA, including cis-9, trans-11 conjugated linoleic acid. Daily gain of the DDGS calves was increased (P=0.01) compared with CON calves, resulting in heavier BW on day 129 (P=0.01). Heavier BW of DDGS calves was maintained through weaning (P=0.01). Timed-artificial insemination (TAI) rates were greater for cows fed DDGS compared with cows fed CON (P<0.02), but dietary treatment had no effect on overall pregnancy rates (P=0.64). In summary, feeding DDGS to lactating beef cows did not change cow BW or BCS, but did improve TAI rates and altered milk composition compared with CON. As a result, male

[Transgenerational impact of chemotherapy: Would the father exposure impact the health of future progeny?

PubMed

Tremblay, A; Beaud, H; Delbès, G

2017-11-01

The number of cancer survivors is increasing and their quality of life is becoming a major public health issue. Cancer treatments reduce men's reproductive health by targeting spermatogenesis. Ultimately, DNA, chromatin and the epigenome of spermatozoa can be altered in cancer survivors. Knowing whether the history of cancer and the treatments received can have consequences on the health of their offspring is therefore a fundamental question for these patients. This review gathers the experimental and epidemiological evidences of the effects observed on the direct descendants and on several generations, and draws up the state of knowledge on the mechanisms potentially involved. Experimental data describe inter- and transgenerational effects of paternal exposure depending on the type of treatment, dose and time of exposure. In the human population, the analysis of the effects specifically due to chemotherapy is still limited because they are often combined with irradiation treatments. However, it appears that chemotherapy agents affect the birth rate but do not have a significant impact on the health of the children born. Nevertheless, the demonstration of modifications of the sperm epigenome in cancer survivors, even after a period of remission, as well as changes in the sperm of the progeny in animal models, suggests a possible transgenerational transmission that remains to be studied in the human population. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Multifaceted, cross-generational costs of hybridization in sibling Drosophila species.

PubMed

Myers, Erin M; Harwell, Tiffany I; Yale, Elizabeth L; Lamb, Abigail M; Frankino, W Anthony

2013-01-01

Maladaptive hybridization, as determined by the pattern and intensity of selection against hybrid individuals, is an important factor contributing to the evolution of prezygotic reproductive isolation. To identify the consequences of hybridization between Drosophila pseudoobscura and D. persimilis, we estimated multiple fitness components for F1 hybrids and backcross progeny and used these to compare the relative fitness of parental species and their hybrids across two generations. We document many sources of intrinsic (developmental) and extrinsic (ecological) selection that dramatically increase the fitness costs of hybridization beyond the well-documented F1 male sterility in this model system. Our results indicate that the cost of hybridization accrues over multiple generations and reinforcement in this system is driven by selection against hybridization above and beyond the cost of hybrid male sterility; we estimate a fitness loss of >95% relative to the parental species across two generations of hybridization. Our findings demonstrate the importance of estimating hybridization costs using multiple fitness measures from multiple generations in an ecologically relevant context; so doing can reveal intense postzygotic selection against hybridization and thus, an enhanced role for reinforcement in the evolution of populations and diversification of species.

The use of the ph1b mutant to induce recombination between the chromosomes of wheat and barley

PubMed Central

Rey, María-Dolores; Calderón, María C.; Prieto, Pilar

2015-01-01

Intensive breeding has led to a narrowing in the genetic base of our major crops. In wheat, access to the extensive gene pool residing in its many and varied relatives (some cultivated, others wild) is hampered by the block on recombination imposed by the Ph1 (Pairing homoeologous 1) gene. Here, the ph1b mutant has been exploited to induced allosyndesis between wheat chromosomes and those of both Hordeum vulgare (cultivated barley) and H. chilense (a wild barley). A number of single chromosome Hordeum sp. substitution and addition lines in wheat were crossed and backcrossed to the ph1b mutant to produce plants in which pairing between the wheat and the non-wheat chromosomes was not suppressed by the presence of Ph1. Genomic in situ hybridization was applied to almost 500 BC1F2 progeny as a screen for allosyndetic recombinants. Chromosome rearrangements were detected affecting H. chilense chromosomes 4Hch, 5Hch, 6Hch, and 7Hch and H. vulgare chromosomes 4Hv, 6Hv, and 7Hv. Two of these were clearly the product of a recombination event involving chromosome 4Hch and a wheat chromosome. PMID:25852713

Contact zone between chromosomal races of Mus musculus domesticus. 2. Fertility and segregation in laboratory-reared and wild mice heterozygous for multiple robertsonian rearrangements.

PubMed

Castiglia, R; Capanna, E

2000-08-01

Litter size, anaphase I nondisjunction and X-Y dissociation at metaphase I were studied in homozygous and heterozygous house mice from a central Italian chromosomal hybrid zone between the CD (2n=22) race and the standard race (2n=40). We also observed the segregation of the two chromosomal forms (Robertsonian and non-Robertsonian) in male and female multiple heterozygotes from the karyotype of their offspring and chromosomal arm counts of metaphase II. Litter size was significantly reduced in the F1 hybrids, but there was no difference in litter size between male and female F1s. Fertility in wild mice decreased with increasing numbers of structural heterozygosities (0-5). Some metacentrics appear to be under meiotic drive but there was no rule as to which of the two forms was favoured in backcrosses. An original observation of a negative correlation between the length of metacentrics and transmission rate was described in hybrids. Slight cosegregation of chromosomes with a similar morphology was present in the progeny of males and females. These observations are discussed in relation to the stability of this hybrid zone through time.

Genome characterization of a breeding line derived from a cross between Oryza sativa and Oryza rufipogon.

PubMed

Keong, B P; Harikrishna, J A

2012-02-01

A preliminary screening was conducted on BC3F1 and BC4F1 backcross families developed from crossing Oryza sativa (MR219) and O. rufipogon (IRGC105491). Despite earlier results showing that O. rufipogon alleles (wild introgression) contributed to both number of panicles (qPPL-2) and tillers (qTPL-2) at loci RM250, RM208, and RM48 in line A20 of the BC2F2 population, we observed that wild introgression was lost at loci RM250 and RM208 but retained at locus RM48 in BC3F1 and BC4F1. Progeny tests conducted utilizing genotype and phenotype data on both BC4F1 and a reference population, BC2F7 (A20 line), did not show significant differences between groups having the MR219 allele and wild introgression at locus RM48. This suggests that there is no additive and transgressive effect of wild introgression in the BC3F1 and BC4F1 generated. The presence of wild introgression was largely due to gene contamination by cross-pollination during field breeding practices.

The locus Om, responsible for the DDK syndrome, maps close to Sigje on mouse chromosome 11.

PubMed

Baldacci, P A; Richoux, V; Renard, J P; Guénet, J L; Babinet, C

1992-01-01

The DDK inbred strain of mouse has a striking particularity: when DDK females are crossed to males of other strains they exhibit a reduced fertility, whereas the reciprocal crosses (non-DDK females x DDK males) are fertile (Wakasugi et al. 1967; Wakasugi 1973). The low fertility results from an early embryonic lethality, the F1 embryos dying near the late morula-early blastocyst stage. Genetic analyses (Wakasugi 1974) and nuclear and cytoplasmic transfers (Renard and Babinet 1986; Babinet et al. 1990; Mann 1986), have shown that the failure of the embroys to develop is due to an incompatibility between a DDK maternally encoded cytoplasmic product and the non-DDK paternal genome. In order to elucidate the genetic determinism of this embryonic lethality, we have analyzed the fertility of male progeny from a backcross BALB/c females x (BALB/c x DDK)F1 males and that of males from a set of recombinant inbred (RI) strains, established from DDK and BALB/c progenitors, when mated with DDK females. Our results indicate that a single locus, Om, is responsible for the DDK syndrome and is located on Chromosome (Chr) 11, very close to the Sigje locus.

Developmental exposure of zebrafish (Danio rerio) to 17α-ethinylestradiol affects non-reproductive behavior and fertility as adults, and increases anxiety in unexposed progeny.

PubMed

Volkova, Kristina; Reyhanian Caspillo, Nasim; Porseryd, Tove; Hallgren, Stefan; Dinnétz, Patrik; Porsch-Hällström, Inger

2015-07-01

Exposure to estrogenic endocrine disruptors (EDCs) during development affects fertility, reproductive and non-reproductive behavior in mammals and fish. These effects can also be transferred to coming generations. In fish, the effects of developmental EDC exposure on non-reproductive behavior are less well studied. Here, we analyze the effects of 17α-ethinylestradiol (EE2) on anxiety, shoaling behavior and fertility in zebrafish after developmental treatment and remediation in clean water until adulthood. Zebrafish embryos were exposed from day 1 to day 80 post fertilization to actual concentrations of 1.2 and 1.6ng/L EE2. After remediation for 82days non-reproductive behavior and fertilization success were analyzed in both sexes. Males and females from the 1.2ng/L group, as well as control males and females, were bred, and behavior of the untreated F1 offspring was tested as adults. Developmental treatment with 1.2 and 1.6ng/L EE2 significantly increased anxiety in the novel tank test and increased shoaling intensity in both sexes. Fertilization success was significantly reduced by EE2 in both sexes when mated with untreated fish of opposite sex. Progeny of fish treated with 1.2ng/L EE2 showed increased anxiety in the novel tank test and increased light avoidance in the scototaxis test compared to control offspring. In conclusion, developmental exposure of zebrafish to low doses of EE2 resulted in persistent changes in behavior and fertility. The behavior of unexposed progeny was affected by their parents' exposure, which might suggest transgenerational effects. Copyright © 2015. Published by Elsevier Inc.

Effects of immobilization by electricity and MS-222 on brown trout broodstock and their progeny

USGS Publications Warehouse

Redman, S.D.; Meinertz, J.R.; Gaikowski, M.P.

1998-01-01

To determine the effects of electrically and chemically induced immobilization on postspawn broodstock and their progeny, age-2 and age-3 female broodstock and age-2 male broodstock of brown trout Salmo trutta were immobilized with electricity or tricaine methanesulfonate (MS-222), stripped of their eggs or milt, and weighed. Eggs taken from electrically immobilized females were fertilized with milt taken from age-2 males that were immobilized with electricity, and eggs taken from females immobilized with MS-222 were fertilized with milt taken from age-2 males that were immobilized with MS-222. After spawning, the mortality and weight of broodstock were compared twice over a 6-month period. Egg viability and growth of offspring fry from each treatment group were also compared. Electricity induced complete and consistent immobilization in brown trout broodstock. Electrically immobilized fish were more easily handled than fish immobilized with MS-222; however, electrically immobilized fish survival (70%) was significantly less than fish immobilized with MS-222 (83%). Broodstock growth differences were only noted at 6 months postexposure, when the mean weight of electrically immobilized fish was slightly less than the weight of fish immobilized with MS-222. Broodstock immobilization by electricity did not reduce egg viability or fry growth.

The effect of a non-starch polysaccharide-hydrolysing enzyme (Rovabio® Excel) on feed intake and body condition of sows during lactation and on progeny growth performance.

PubMed

Walsh, M C; Geraert, P A; Maillard, R; Kluess, J; Lawlor, P G

2012-10-01

A total of 200 (Large White × Landrace) sows were used in a 39-day study to evaluate the effects of feeding a non-starch polysaccharide (NSP)-hydrolysing enzyme multicomplex (Rovabio(®) Excel) in conjunction with a high- or reduced nutrient-density diet during lactation on sow body condition, feed intake and progeny performance. Eight sows were selected each week for 25 weeks, blocked by parity and BW into groups of four, and within the block randomly assigned to one of the four treatments (n = 50/treatment). Treatments were: (1) LND: low energy (13.14 MJ of DE/kg), low CP (15%) diet; (2) LND + RE: LND with 50 mg/kg NSP-hydrolysing enzyme; (3) HND: high energy (14.5 MJ of DE/kg), high CP (16.5%) diet; and (4) HND + RE: HND with 50 mg/kg NSP-hydrolysing enzyme. Sows were fed treatment diets from day 109 of gestation until the day of subsequent service. Between weaning and re-service, Rovabio(®) Excel addition to LND diets resulted in an increase in energy intake; however, a reduction was observed when supplemented to the HND diet (P < 0.05). The inclusion of Rovabio(®) Excel increased feed and energy intake during week 3 (days 15 to 21) of lactation (P < 0.05). Sows fed diets supplemented with Rovabio(®) Excel had greater back-fat depth at weaning and service (P < 0.05); however, the magnitude of change in back-fat depth during lactation and from farrowing to service was not different between treatments. Feeding the HND diet increased energy intake before farrowing, throughout lactation and during the weaning to service interval (P < 0.01); however, overall, average daily feed intake tended to be reduced (P < 0.10). At service, sows fed the HND diet were heavier than sows fed the LND diet (P < 0.05); however, the magnitude of change in BW between treatments was not different. Feeding the HND diet to sows resulted in a tendency for heavier piglets at birth (P = 0.10) that tended to grow at a faster rate and be heavier at weaning than piglets from sows fed the

Application of biomaterials to advance induced pluripotent stem cell research and therapy

PubMed Central

Tong, Zhixiang; Solanki, Aniruddh; Hamilos, Allison; Levy, Oren; Wen, Kendall; Yin, Xiaolei; Karp, Jeffrey M

2015-01-01

Derived from any somatic cell type and possessing unlimited self-renewal and differentiation potential, induced pluripotent stem cells (iPSCs) are poised to revolutionize stem cell biology and regenerative medicine research, bringing unprecedented opportunities for treating debilitating human diseases. To overcome the limitations associated with safety, efficiency, and scalability of traditional iPSC derivation, expansion, and differentiation protocols, biomaterials have recently been considered. Beyond addressing these limitations, the integration of biomaterials with existing iPSC culture platforms could offer additional opportunities to better probe the biology and control the behavior of iPSCs or their progeny in vitro and in vivo. Herein, we discuss the impact of biomaterials on the iPSC field, from derivation to tissue regeneration and modeling. Although still exploratory, we envision the emerging combination of biomaterials and iPSCs will be critical in the successful application of iPSCs and their progeny for research and clinical translation. PMID:25766254

Winter Iinjury of American chestnut seedlings grown in a common garden at the species' northern range limit

Treesearch

Paul G. Schaberg; Thomas M. Saielli; Gary J. Hawley; Joshua M. Halman; Kendra M. Gurney

2013-01-01

Hybridization of American chestnut (Castanea dentata) with Chinese chestnut (C. mollissima), followed by backcrossing to American chestnut, is conducted to increase the resistance of resulting stock to chestnut blight, caused by the fungal pathogen Cryphonectria parasitica (Murr.) Barr. Backcross breeding is...

Preliminary lung cancer risk assessment of exposure to radon progeny for Transylvania, Romania.

PubMed

Truta-Popa, Lucia-Adina; Dinu, Alexandra; Dicu, Tiberius; Szacsvai, Kinga; Cosma, Constantin; Hofmann, Werner

2010-09-01

The objective of the present study was to assess the lung cancer risk induced by exposures to radon progeny of people living in some areas of Transylvania, Romania. Indoor radon concentrations were measured in 667 dwellings of Stei area, Cluj, Bistrita-Nasaud, Sibiu, and Alba counties. Measurements were performed using CR-39 track detectors, exposed for a minimum of 3 mo. Average annual radon concentrations were 232, 114, 71, 62, and 161 Bq m for Stei area, Cluj, Bistrita-Nasaud, Sibiu, and Alba, respectively. The linear risk model of Darby was used to simulate the dose-effect relationship and relative lung cancer risk at low doses of alpha particles specific to residential radon exposures. Predicted relative risks at the measured exposure levels, together with information on the total number of reported lung cancer deaths and the number of people living in these regions, enabled us to estimate the fraction of lung cancer cases in each area that is attributable to radon. These percentages are 16.67% for Stei area, 9.09% for Cluj, 5.66% for Bistrita-Nasaud, 4.76% for Sibiu, and 12.28% for Alba county among lifetime non-smokers. Assuming that the smoking rates are similar for the investigated regions (10.72% smokers among men and 5.95% among women), around 64 to 69% of the total number of annual lung cancer deaths, stratified by sex, would be attributed to radon and occur among smoking male population, and around 35 to 44% would be attributed to radon and occur among smoking female population.

A Pooled Sequencing Approach Identifies a Candidate Meiotic Driver in Drosophila

PubMed Central

Wei, Kevin H.-C.; Reddy, Hemakumar M.; Rathnam, Chandramouli; Lee, Jimin; Lin, Deanna; Ji, Shuqing; Mason, James M.; Clark, Andrew G.; Barbash, Daniel A.

2017-01-01

Meiotic drive occurs when a selfish element increases its transmission frequency above the Mendelian ratio by hijacking the asymmetric divisions of female meiosis. Meiotic drive causes genomic conflict and potentially has a major impact on genome evolution, but only a few drive loci of large effect have been described. New methods to reliably detect meiotic drive are therefore needed, particularly for discovering moderate-strength drivers that are likely to be more prevalent in natural populations than strong drivers. Here, we report an efficient method that uses sequencing of large pools of backcross (BC1) progeny to test for deviations from Mendelian segregation genome-wide with single-nucleotide polymorphisms (SNPs) that distinguish the parental strains. We show that meiotic drive can be detected by a characteristic pattern of decay in distortion of SNP frequencies, caused by recombination unlinking the driver from distal loci. We further show that control crosses allow allele-frequency distortion caused by meiotic drive to be distinguished from distortion resulting from developmental effects. We used this approach to test whether chromosomes with extreme telomere-length differences segregate at Mendelian ratios, as telomeric regions are a potential hotspot for meiotic drive due to their roles in meiotic segregation and multiple observations of high rates of telomere sequence evolution. Using four different pairings of long and short telomere strains, we find no evidence that extreme telomere-length variation causes meiotic drive in Drosophila. However, we identify one candidate meiotic driver in a centromere-linked region that shows an ∼8% increase in transmission frequency, corresponding to a ∼54:46 segregation ratio. Our results show that candidate meiotic drivers of moderate strength can be readily detected and localized in pools of BC1 progeny. PMID:28258181

Genomic Analysis of the Appearance of Ovarian Mast Cells in Neonatal MRL/MpJ Mice

PubMed Central

Nakamura, Teppei; Sakata, Yuko; Otsuka-Kanazawa, Saori; Ichii, Osamu; Chihara, Masataka; Nagasaki, Ken-ichi; Namiki, Yuka; Kon, Yasuhiro

2014-01-01

In MRL/MpJ mice, ovarian mast cells (OMCs) are more abundant than in other mouse strains, and tend to distribute beneath the ovarian surface epithelium at birth. This study investigated the factors regulating the appearance of neonatal OMCs in progeny of the cross between MRL/MpJ and C57BL/6N strains. F1 neonates had less than half the number of OMCs than MRL/MpJ. Interestingly, MRLB6F1 had more neonatal OMCs than B6MRLF1, although they were distributed over comparable areas. Furthermore, in MRL/MpJ fetuses for which parturition was delayed until embryonic day 21.5, the number of OMCs was significantly higher than in age-matched controls at postnatal day 2. These results suggest that the number of OMCs was influenced by the environmental factors during pregnancy. Quantitative trait locus analysis using N2 backcross progeny revealed two significant loci on chromosome 8: D8Mit343–D8Mit312 for the number of OMCs and D8Mit86–D8Mit89 for their distribution, designated as mast cell in the ovary of MRL/MpJ 1 (mcom1) and mcom2, respectively. Among MC migration-associated genes, ovarian expression of chemokine (C-C motif) ligand 17 at mcom1 locus was significantly higher in MRL/MpJ than in C57BL/6N, and positively correlated with the expression of OMC marker genes. These results indicate that the appearance of neonatal OMCs in MRL/MpJ is controlled by environmental factors and filial genetic factors, and that the abundance and distribution of OMCs are regulated by independent filial genetic elements. PMID:24956472

Cytogenetics and stripe rust resistance of wheat-Thinopyrum elongatum hybrid derivatives.

PubMed

Li, Daiyan; Long, Dan; Li, Tinghui; Wu, Yanli; Wang, Yi; Zeng, Jian; Xu, Lili; Fan, Xing; Sha, Lina; Zhang, Haiqin; Zhou, Yonghong; Kang, Houyang

2018-01-01

Amphidiploids generated by distant hybridization are commonly used as genetic bridge to transfer desirable genes from wild wheat species into cultivated wheat. This method is typically used to enhance the resistance of wheat to biotic or abiotic stresses, and to increase crop yield and quality. Tetraploid Thinopyrum elongatum exhibits strong adaptability, resistance to stripe rust and Fusarium head blight, and tolerance to salt, drought, and cold. In the present study, we produced hybrid derivatives by crossing and backcrossing the Triticum durum-Th. elongatum partial amphidiploid ( Trititrigia 8801, 2 n  = 6 ×  = 42, AABBEE) with wheat cultivars common to the Sichuan Basin. By means of cytogenetic and disease resistance analyses, we identified progeny harboring alien chromosomes and measured their resistance to stripe rust. Hybrid progenies possessed chromosome numbers ranging from 40 to 47 (mean = 42.72), with 40.0% possessing 42 chromosomes. Genomic in situ hybridization revealed that the number of alien chromosomes ranged from 1 to 11. Out of the 50 of analyzed lines, five represented chromosome addition (2 n  = 44 = 42 W + 2E) and other five were chromosome substitution lines (2 n  = 42 = 40 W + 2E). Importantly, a single chromosome derived from wheat- Th. elongatum intergenomic Robertsonian translocations chromosome was occurred in 12 lines. Compared with the wheat parental cultivars ('CN16' and 'SM482'), the majority (70%) of the derivative lines were highly resistant to strains of stripe rust pathogen known to be prevalent in China. The findings suggest that these hybrid-derivative lines with stripe rust resistance could potentially be used as germplasm sources for further wheat improvement.

Comparison of pure Holsteins to crossbred Holsteins with Norwegian Red cattle in first and second generations.

PubMed

Ezra, E; Van Straten, M; Weller, J I

2016-08-01

A total of 1922 first generation crossbred cows born between 2005 and 2012 produced by inseminating purebred Israeli Holstein cows with Norwegian Red semen, and 7487 purebred Israeli Holstein cows of the same age in the same 50 herds were analyzed for production, calving traits, fertility, calving diseases, body condition score, abortion rate and survival under intensive commercial management conditions. Holstein cows were higher than crossbreds for 305-day milk, fat and protein production. Differences were 764, 1244, 1231 for kg milk; 23.4, 37.4, 35.6 for kg fat, and 16.7, 29.8, 29.8 for kg protein; for parities 1 through 3. Differences for fat concentration were not significant; while crossbred cows were higher for protein concentration by 0.06% to 0.08%. Differences for somatic cells counts were not significant. Milk production persistency was higher for Holstein cows by 5, 8.3 and 8% in parities 1 through 3. Crossbred cows were higher for conception status by 3.1, 3.6 and 4.7% in parities 1 through 3. Rates of metritis for Holsteins were higher than the crossbred cows by 7.8, 4.6 and 3.4% in parities 1 to 3. Differences for incidence of abortion, dystocia, ketosis and milk fever were not significant. Holstein cows were lower than crossbred cows for body condition score for all three parities, with differences of 0.2 to 0.4 units. Contrary to comparisons in other countries, herd-life was higher for Holsteins by 79 days. A total of 6321 Holstein cows born between 2007 and 2011 were higher than 765 progeny of crossbred cows backcrossed to Israeli Holsteins of the same ages for milk, fat and protein production. Differences were 279, 537, 542 kg milk; 10.5, 17.7, 17.0 kg fat and 6.2, 12.9, 13.2 kg protein for parities 1 through 3. Differences for fat concentration were not significant, while backcross cows were higher for protein percentage by 0.02% to 0.04%. The differences for somatic cell score, conception rate, and calving diseases other than metritis, were not

Simulating ocean acidification and CO2 leakages from carbon capture and storage to assess the effects of pH reduction on cladoceran Moina mongolica Daday and its progeny.

PubMed

Wang, Zaosheng; Wang, Youshao; Yan, Changzhou

2016-07-01

In order to evaluate the effects of pH reduction in seawater as a result of increasing levels of atmospheric CO2, laboratory-scale experiments simulating the scenarios of ocean acidification (OA) and CO2 leakages of carbon capture and storage (CCS) were performed using the model organism Moina mongolica Daday. The LpH50s calculated in cladoceran toxicity tests showed that M. mongolica exhibited intermediate sensitivity to OA, which varied among species and with ontogeny, when compared with different phyla or classes of marine biota. Survival, reproduction and fecundity of parthenogenetic females were evaluated after 21-day exposures. Results showed that increased acidity significantly reduced the rate of reproduction of M. mongolica resulting in a decreased intrinsic rate of natural increase (rm) across the gradients of pH reduction. The analysis of macromolecule contents in neonates suggested that nutritional status in progeny from all broods were significantly reduced as seawater pH decreased, with increasing magnitude in latter broods, except the contents of protein from two former broods and lipids from the first brood. Our findings clearly showed that for this ecologically and economically important fish species, the negative effects of pH reduction on both "quantity" and "quality" of progeny may have far-reaching implications, providing direct evidence that OA could influence the energetic transfer of marine food web and ecosystem functions in acidified oceans in the future. Copyright © 2016 Elsevier Ltd. All rights reserved.

Bombyx mori nucleopolyhedrovirus BM5 protein regulates progeny virus production and viral gene expression

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

Kokusho, Ryuhei, E-mail: kokusho@ss.ab.a.u-tokyo.a

2016-11-15

Bombyx mori nucleopolyhedrovirus (BmNPV) orf5 (Bm5) is a core gene of lepidopteran baculoviruses and encodes the protein with the conserved amino acid residues (DUF3627) in its C-terminus. Here, we found that Bm5 disruption resulted in lower titers of budded viruses and fewer numbers of occlusion bodies (OBs) in B. mori cultured cells and larvae, although viral genome replication was not affected. Bm5 disruption also caused aberrant expression of various viral genes at the very late stage of infection. Immunocytochemical analysis revealed that BM5 localized to the nuclear membrane. We also found that DUF3627 is important for OB production, transcriptional regulationmore » of viral genes, and subcellular localization of BM5. Compared with wild-type BmNPV infection, larval death was delayed when B. mori larvae were infected with Bm5 mutants. These results suggest that BM5 is involved in progeny virus production and regulation of viral gene expression at the very late stage of infection. -- Highlights: •The role of BmNPV BM5 protein was examined in B. mori cultured cells and larvae. •BM5 contributes to efficient production of budded viruses and occlusion bodies. •BM5 regulates viral gene expression at the very late stage of infection. •BM5 dominantly localizes to the nuclear membrane. •Bm5 mutant showed v-cath down-regulation and resulting delay of larval death.« less

More efficient repair of DNA double-strand breaks in skeletal muscle stem cells compared to their committed progeny.

PubMed

Vahidi Ferdousi, Leyla; Rocheteau, Pierre; Chayot, Romain; Montagne, Benjamin; Chaker, Zayna; Flamant, Patricia; Tajbakhsh, Shahragim; Ricchetti, Miria

2014-11-01

The loss of genome integrity in adult stem cells results in accelerated tissue aging and is possibly cancerogenic. Adult stem cells in different tissues appear to react robustly to DNA damage. We report that adult skeletal stem (satellite) cells do not primarily respond to radiation-induced DNA double-strand breaks (DSBs) via differentiation and exhibit less apoptosis compared to other myogenic cells. Satellite cells repair these DNA lesions more efficiently than their committed progeny. Importantly, non-proliferating satellite cells and post-mitotic nuclei in the fiber exhibit dramatically distinct repair efficiencies. Altogether, reduction of the repair capacity appears to be more a function of differentiation than of the proliferation status of the muscle cell. Notably, satellite cells retain a high efficiency of DSB repair also when isolated from the natural niche. Finally, we show that repair of DSB substrates is not only very efficient but, surprisingly, also very accurate in satellite cells and that accurate repair depends on the key non-homologous end-joining factor DNA-PKcs. Copyright © 2014. Published by Elsevier B.V.

A method for accelerated trait conversion in plant breeding.

PubMed

Lewis, Ramsey S; Kernodle, S P

2009-05-01

Backcrossing is often used in cultivar development to transfer one or a few genes to desired genetic backgrounds. The duration necessary to complete such 'trait conversions' is largely dependent upon generation times. Constitutive overexpression of the Arabidopsis thaliana gene FT (FLOWERING LOCUS T) induces early-flowering in many plants. Here, we used tobacco (Nicotiana tabacum L.) as a model system to propose and examine aspects of a modified backcross procedure where transgenic FT overexpression is used to reduce generation time and accelerate gene transfer. In this method, the breeder would select for an FT transgene insertion and the trait(s) of interest at each backcross generation except the last. In the final generation, selection would be conducted for the trait(s) of interest, but against FT, to generate the backcross-derived trait conversion. We demonstrate here that constitutive FT overexpression functions to dramatically reduce days-to-flower similarly in diverse tobacco genetic backgrounds. FT-containing plants flowered in an average of 39 days, in comparison with 87-138 days for non-FT plants. Two FT transgene insertions were found to segregate independently of several disease resistance genes often the focus of backcrossing in tobacco. In addition, no undesirable epigenetic effects on flowering time were observed once FT was segregated away. The proposed system would reduce the time required to complete a trait conversion in tobacco by nearly one-half. These features suggest the possible value of this modified backcrossing system for tobacco or other crop species where long generation times or photoperiod sensitivity may impede timely trait conversion.

A new simple technique for rearing F1 progeny from females of the Simulium damnosum Theobald complex.

PubMed

Raybould, J N; Barro, T; Sawadogo, R; Mordzifa, F

1982-06-01

Laboratory rearing of Simulium damnosum complex species enables female adults to be indirectly identified from their larval progeny. A simple, readily transportable rearing apparatus was developed for investigations by the Onchocerciasis Control programme by using unbreakable, easily packed and reassembled parts and by feeding the larvae at least partly with living green algae (Chlorophyceae) cultured in the laboratory. Although the larvae are sensitive to excess nitrogen compounds, the use of algae and a large volume of water obviated the need for a separate purification system in which water was circulated by an A/C electrical centrifugal pump between a container and an inclined trough in which most of the larvae developed. The rate of development was rapid giving rise to full size larvae (suitable for cytotaxonomic determination), pupae and adults. The adults were attracted into a collecting device by light. Developments to protect the larvae during electrical power failures included a slow-drying wooden rearing trough and an automatic switch to an alternative D/C power supply and pump. This technique has been in general use in O.C.P. laboratories in Benin, Ghana, Ivory Coast and Upper Volta and many thousands of larvae have been reared.

Mutation rates at the glycophorin A and HPRT loci in uranium miners exposed to radon progeny.

PubMed Central

Shanahan, E M; Peterson, D; Roxby, D; Quintana, J; Morely, A A; Woodward, A

1996-01-01

OBJECTIVES--To find whether a relation exists between estimated levels of exposure to radon and its progeny and mutations in hypoxanthine phosphoribosyl transferase (HPRT) and glycophorin A in a cohort of former uranium miners. METHODS--A cohort study involving a sample of miners from the Radium Hill uranium mine in South Australia, which operated from 1952 to 1961. Radiation exposures underground at Radium Hill were estimated from historical radon gas measures with a job exposure matrix. Workers from the mine who worked exclusively above ground according to mine records were selected as controls. In 1991-2 miners were interviewed and blood taken for measurement of somatic mutations. Mutation rates for HPRT and glycophorin A were estimated with standard assay techniques. RESULTS--Homozygous mutations of glycophorin A were increased in underground miners (P = 0.0027) and the mutation rate tended to rise with increasing exposure with the exception of the highest exposure (> 10 working level months). However, there was no association between place of work and either the hemizygous mutations of glycophorin A or the HPRT mutation. CONCLUSIONS--There may be an association between glycophorin A mutations and previous occupational exposure to ionising radiation. However, not enough is known at present to use these assays as biomarkers for historical exposure in underground mining cohorts. PMID:8704866

Different degree of paternal mtDNA leakage between male and female progeny in interspecific Drosophila crosses

PubMed Central

Dokianakis, Emmanouil; Ladoukakis, Emmanuel D

2014-01-01

Maternal transmission of mitochondrial DNA (mtDNA) in animals is thought to prevent the spread of selfish deleterious mtDNA mutations in the population. Various mechanisms have been evolved independently to prevent the entry of sperm mitochondria in the embryo. However, the increasing number of instances of paternal mtDNA leakage suggests that these mechanisms are not very effective. The destruction of sperm mitochondria in mammalian embryos is mediated by nuclear factors. Also, the destruction of paternal mitochondria in intraspecific crosses is more effective than in interspecific ones. These observations have led to the hypothesis that leakage of paternal mtDNA (and consequently mtDNA recombination owing to ensuing heteroplasmy) might be more common in inter- than in intraspecific crosses and that it should increase with phylogenetic distance of hybridizing species. We checked paternal leakage in inter- and intraspecific crosses in Drosophila and found little evidence for this hypothesis. In addition, we have observed a higher level of leakage among male than among female progeny from the same cross. This is the first report of sex-specific leakage of paternal mtDNA. It suggests that paternal mtDNA leakage might not be a stochastic result of an error-prone mechanism, but rather, it may be under complex genetic control. PMID:25077015

Maternal effects and cancer risk in the progeny of mice exposed to X-rays before conception.

PubMed

Dasenbrock, Clemens; Tillmann, Thomas; Ernst, Heinrich; Behnke, Wolfgang; Kellner, Rupert; Hagemann, Gerd; Kaever, Volkhard; Kohler, Manfred; Rittinghausen, Susanne; Mohr, Ulrich; Tomatis, Lorenzo

2005-04-01

To investigate in an animal model whether preconceptual X-ray exposure leads to an altered tumor rate and spectrum in the offspring, a transgeneration carcinogenesis study was carried out. Female mice received X-ray irradiation (2 x 2 Gray) 2 weeks prior to mating with untreated males. After weaning, half of the descendants were exposed for 6 months to the immunomodulating and tumor-promoting compound cyclosporine A (CsA) by diet, the others remained untreated. The animals were maintained for their entire lifespan, terminal sacrifices were carried out after 28 months. Complete autopsy was performed, and three protocol organs (lung, liver and spleen) were examined histologically, together with any suspicious lesions in other organs. Fertility and the lifetime of the maternal mice were reduced by the X-ray irradiation, and their incidence of lung and liver tumors was increased as compared to non-irradiated mice. The descendants of all groups revealed comparable body weights and mortality rates. The incidence of hematopoietic/lymphoreticular tissue tumors increased in the female hybrids by 6 months of CsA-treatment. A higher incidence of lung and liver tumors in the sham-treated male progeny of irradiated mothers was detected, pointing to a possible germ cell-transmitted alteration initiated by the preconceptual maternal X-ray exposure.

Different degree of paternal mtDNA leakage between male and female progeny in interspecific Drosophila crosses.

PubMed

Dokianakis, Emmanouil; Ladoukakis, Emmanuel D

2014-07-01

Maternal transmission of mitochondrial DNA (mtDNA) in animals is thought to prevent the spread of selfish deleterious mtDNA mutations in the population. Various mechanisms have been evolved independently to prevent the entry of sperm mitochondria in the embryo. However, the increasing number of instances of paternal mtDNA leakage suggests that these mechanisms are not very effective. The destruction of sperm mitochondria in mammalian embryos is mediated by nuclear factors. Also, the destruction of paternal mitochondria in intraspecific crosses is more effective than in interspecific ones. These observations have led to the hypothesis that leakage of paternal mtDNA (and consequently mtDNA recombination owing to ensuing heteroplasmy) might be more common in inter- than in intraspecific crosses and that it should increase with phylogenetic distance of hybridizing species. We checked paternal leakage in inter- and intraspecific crosses in Drosophila and found little evidence for this hypothesis. In addition, we have observed a higher level of leakage among male than among female progeny from the same cross. This is the first report of sex-specific leakage of paternal mtDNA. It suggests that paternal mtDNA leakage might not be a stochastic result of an error-prone mechanism, but rather, it may be under complex genetic control.

Use of wild genotypes in breeding program increases strawberry fruit sensorial and nutritional quality.

PubMed

Diamanti, Jacopo; Mazzoni, Luca; Balducci, Francesca; Cappelletti, Roberto; Capocasa, Franco; Battino, Maurizio; Dobson, Gary; Stewart, Derek; Mezzetti, Bruno

2014-05-07

This study evaluated 20 advanced selections, derived from a strawberry interspecific backcross program, and their parents for fruit weight, commercial yield, acidity, sugar content, antioxidant capacity, and phenol and anthocyanin contents. Phytochemical profiling analysis was performed to determine the compositional characteristics of the improved selections in comparison with their parents and an important commercial variety ('Elsanta'). Advanced selections showed substantial improvement for agronomic and nutritional quality parameters. From the profiling analysis there was evidence for specific improvements in fruit phytochemical contents; new advanced selections had substantially increased fruit flavonol, anthocyanin, and ellagitannin contents compared to their parent cultivar 'Romina' and, for flavonols and ellagitannins, compared to a standard cultivar 'Elsanta'. Such results confirm that an appropriate breeding program that includes wild strawberry germplasm can produce new strawberry cultivars with a well-defined improvement in fruit nutritional and nutraceutical values.

Msx1-Positive Progenitors in the Retinal Ciliary Margin Give Rise to Both Neural and Non-neural Progenies in Mammals.

PubMed

Bélanger, Marie-Claude; Robert, Benoit; Cayouette, Michel

2017-01-23

In lower vertebrates, stem/progenitor cells located in a peripheral domain of the retina, called the ciliary margin zone (CMZ), cooperate with retinal domain progenitors to build the mature neural retina. In mammals, it is believed that the CMZ lacks neurogenic potential and that the retina develops from one pool of multipotent retinal progenitor cells (RPCs). Here we identify a population of Msx1-expressing progenitors in the mouse CMZ that is both molecularly and functionally distinct from RPCs. Using genetic lineage tracing, we report that Msx1 progenitors have unique developmental properties compared with RPCs. Msx1 lineages contain both neural retina and non-neural ciliary epithelial progenies and overall generate fewer photoreceptors than classical RPC lineages. Furthermore, we show that the endocytic adaptor protein Numb regulates the balance between neural and non-neural fates in Msx1 progenitors. These results uncover a population of CMZ progenitors, distinct from classical RPCs, that also contributes to mammalian retinogenesis. Copyright © 2017 Elsevier Inc. All rights reserved.

Investigation of genetic factors influencing duration of copulation in "eastern" and "western" Drosophila athabasca.

PubMed

Patty, R A

1975-05-01

Observations of mating behaviour were made on "eastern" and "western" Drosophila athabasca and on flies of mixed genetic background. Duration of copulation in mixed combinations of D. athabasca is determined by the male. In F1 males the source of X-chromosome, whether eastern or western, partly determined suration of copulation. However, durations of copulation of backcross males suggest autosomal influence, in that males derived from an eastern backcross demonstrate significantly shorter durations than males derived from a western backcross. In addition, durations of copulation from F2 combinations exhibit greater variance than the F1 and thereby represent evidence of F2 segregation.

Identification of full-length transmitted/founder viruses and their progeny in primary HIV-1 infection

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

Korber, Bette; Hraber, Peter; Giorgi, Elena

2009-01-01

Identification of transmitted/founder virus genomes and their progeny by is a novel strategy for probing the molecular basis of HIV-1 transmission and for evaluating the genetic imprint of viral and host factors that act to constrain or facilitate virus replication. Here, we show in a cohort of twelve acutely infected subjects (9 clade B; 3 clade C), that complete genomic sequences of transmitted/founder viruses could be inferred using single genome amplification of plasma viral RNA, direct amplicon sequencing, and a model of random virus evolution. This allowed for the precise identification, chemical synthesis, molecular cloning, and biological analysis of thosemore » viruses actually responsible for productive clinical infection and for a comprehensive mapping of sequential viral genomes and proteomes for mutations that are necessary or incidental to the establishment of HIV-1 persistence. Transmitted/founder viruses were CD4 and CCR5 tropic, replicated preferentially in activated primary T-Iymphocytes but not monocyte-derived macrophages, and were effectively shielded from most heterologous or broadly neutralizing antibodies. By 3 months of infection, the evolving viral quasispecies in three subjects showed mutational fixation at only 2-5 discreet genomic loci. By 6-12 months, mutational fixation was evident at 18-27 genomic loci. Some, but not all, of these mutations were attributable to virus escape from cytotoxic Tlymphocytes or neutralizing antibodies, suggesting that other viral or host factors may influence early HIV -1 fitness.« less

Ovipositional response elicited by normal, irradiated, F$sub 1$ male progeny, or castrated male Trichoplusia ni (Lepidoptera: Noctuidae)

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

Karpenko, C.P.; North, D.T.

1973-11-01

The ovipositional response of untreated Trichoplusia ni (Hubner) females that had mated to unirradiated, irradiated, F/sub 1/ male progeny from irradiated males, or castrated males was studied. Females that mated with irradiated males or F/sub 1/ sons of irradiated males oviposited fewer eggs than females that mated with control males, when all females had received a normal quantity of eupyrene and apyrene sperm. Irradiated males and F/sub 1/ sons of irradiated males that transferred an apparently normal sperm complement elicited significantly better oviposition from untreated females than did treated males that transferred mostly apyrene sperm, apyrene sperm only, or nomore » sperm. Males in the latter categories elicited a better ovipositional response from the untreated females than was observed in virgin females. Normal eupyrene sperm and possibly at least 1 accessory fiuid are required to initiate a completely normal ovipositional response in cabbage looper females. The accessory secretion triggers a significant increase in oviposition, but the greatest increase occurs when males contribute normal amounts of eupyrene sperm. The initiation of oviposition and female receptivity may be closely related in this species. (auth)« less

Effect of cytoplasmic diversity on post anthesis heat tolerance in wheat

USDA-ARS?s Scientific Manuscript database

The nuclear genomes of ten alloplasmic lines were substituted by backcrossing four or five times using ‘Karl 92’, ‘Ventnor’, ‘U1275’ and ‘Jagger’ as recurrent parents to study the cytoplasmic effects on heat tolerance. During the final backcross, reciprocal crosses were made to develop NILs (Near Is...

Label-free separation of human embryonic stem cells and their differentiating progenies by phasor fluorescence lifetime microscopy

NASA Astrophysics Data System (ADS)

Stringari, Chiara; Sierra, Robert; Donovan, Peter J.; Gratton, Enrico

2012-04-01

We develop a label-free optical technique to image and discriminate undifferentiated human embryonic stem cells (hESCs) from their differentiating progenies in vitro. Using intrinsic cellular fluorophores, we perform fluorescence lifetime microscopy (FLIM) and phasor analysis to obtain hESC metabolic signatures. We identify two optical biomarkers to define the differentiation status of hESCs: Nicotinamide adenine dinucleotide (NADH) and lipid droplet-associated granules (LDAGs). These granules have a unique lifetime signature and could be formed by the interaction of reactive oxygen species and unsaturated metabolic precursor that are known to be abundant in hESC. Changes in the relative concentrations of these two intrinsic biomarkers allow for the discrimination of undifferentiated hESCs from differentiating hESCs. During early hESC differentiation we show that NADH concentrations increase, while the concentration of LDAGs decrease. These results are in agreement with a decrease in oxidative phosphorylation rate. Single-cell phasor FLIM signatures reveal an increased heterogeneity in the metabolic states of differentiating H9 and H1 hESC colonies. This technique is a promising noninvasive tool to monitor hESC metabolism during differentiation, which can have applications in high throughput analysis, drug screening, functional metabolomics and induced pluripotent stem cell generation.

Electrical Capacitance as a Predictor of Root Dry Weight in Shrub Willow ( Salix; Salicaceae) Parents and Progeny

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

Carlson, Craig H.; Smart, Lawrence B.

Here, the root biomass is an important trait often disregarded in woody perennial selection due to the challenge and expense of accurately and efficiently measuring large populations. In this study, we aim to develop a simple method that can predict root dry weight within a diverse shrub willow ( Salix) breeding population representing species hybrids and their parents using root electrical capacitance (REC). The REC method was tested on plants started from cuttings and grown in pots with potting mix in the greenhouse for 11 wk to assess the relationship of REC with 24 biomass traits and its usefulness inmore » allometric models for root and stem dry biomass. As a result, strong linear and positive correlations were found between REC and root dry biomass (r = 0.88). The total proportion of variance of root and stem dry biomass explained by predictors in multiple regression was 85% and 69%, respectively. The relative importance of predictor variables in allometric models was dominated by the contribution of REC. Here, this work provides an efficient and nondestructive technique to indirectly quantify root biomass of genetically diverse shrub willow progeny, which has great promise for selection of genotypes with varying root biomass and for the accurate estimation of belowground carbon sequestration.« less

Electrical Capacitance as a Predictor of Root Dry Weight in Shrub Willow ( Salix; Salicaceae) Parents and Progeny

DOE PAGES

Carlson, Craig H.; Smart, Lawrence B.

2016-08-19

Here, the root biomass is an important trait often disregarded in woody perennial selection due to the challenge and expense of accurately and efficiently measuring large populations. In this study, we aim to develop a simple method that can predict root dry weight within a diverse shrub willow ( Salix) breeding population representing species hybrids and their parents using root electrical capacitance (REC). The REC method was tested on plants started from cuttings and grown in pots with potting mix in the greenhouse for 11 wk to assess the relationship of REC with 24 biomass traits and its usefulness inmore » allometric models for root and stem dry biomass. As a result, strong linear and positive correlations were found between REC and root dry biomass (r = 0.88). The total proportion of variance of root and stem dry biomass explained by predictors in multiple regression was 85% and 69%, respectively. The relative importance of predictor variables in allometric models was dominated by the contribution of REC. Here, this work provides an efficient and nondestructive technique to indirectly quantify root biomass of genetically diverse shrub willow progeny, which has great promise for selection of genotypes with varying root biomass and for the accurate estimation of belowground carbon sequestration.« less

Development and characterization of mutant winter wheat (Triticum aestivum L.) accessions resistant to the herbicide quizalofop.

PubMed

Ostlie, Michael; Haley, Scott D; Anderson, Victoria; Shaner, Dale; Manmathan, Harish; Beil, Craig; Westra, Phillip

2015-02-01

New herbicide resistance traits in wheat were produced through the use of induced mutagenesis. While herbicide-resistant crops have become common in many agricultural systems, wheat has seen few introductions of herbicide resistance traits. A population of Hatcher winter wheat treated with ethyl methanesulfonate was screened with quizalofop to identify herbicide-resistant plants. Initial testing identified plants that survived multiple quizalofop applications. A series of experiments were designed to characterize this trait. In greenhouse studies the mutants exhibited high levels of quizalofop resistance compared to non-mutant wheat. Sequencing ACC1 revealed a novel missense mutation causing an alanine to valine change at position 2004 (Alopecurus myosuroides reference sequence). Plants carrying single mutations in wheat's three genomes (A, B, D) were identified. Acetyl co-enzyme A carboxylase in resistant plants was 4- to 10-fold more tolerant to quizalofop. Populations of segregating backcross progenies were developed by crossing each of the three individual mutants with wild-type wheat. Experiments conducted with these populations confirmed largely normal segregation, with each mutant allele conferring an additive level of resistance. Further tests showed that the A genome mutation conferred the greatest resistance and the B genome mutation conferred the least resistance to quizalofop. The non-transgenic herbicide resistance trait identified will enhance weed control strategies in wheat.

Concordant morphological and molecular clines in a contact zone of the Common and Spined toad (Bufo bufo and B. spinosus) in the northwest of France.

PubMed

Arntzen, Jan W; Trujillo, Tania; Butôt, Roland; Vrieling, Klaas; Schaap, Onno; Gutiérrez-Rodríguez, Jorge; Martínez-Solano, Iñigo

2016-01-01

Hybrid zones are regions where individuals of two species meet and produce hybrid progeny, and are often regarded as natural laboratories to understand the process of species formation. Two microevolutionary processes can take place in hybrid zones, with opposing effects on population differentiation. Hybridization tends to produce genetic homogenization, reducing species differences, whereas the presence of mechanisms of reproductive isolation result in barriers to gene flow, maintaining or increasing differences between taxa. Here we study a contact zone between two hybridizing toad species, Bufo bufo and B. spinosus , through a combination of molecular (12 polymorphic microsatellites, four nuclear and two mitochondrial SNP markers) and morphological data in a transect in the northwest of France. The results show largely concordant clines across markers, defining a narrow hybrid zone of ca. 30 km wide. Most hybrids in the centre of the contact zone are classified as F 2 or backcrossed individuals, with no individuals assigned to the F 1 hybrid class. We discuss the implications of these results for our understanding of the evolutionary history of these species. We anticipate that the toad contact zone here described will become an important asset in the study of hybrid zone dynamics and evolutionary biology because of its easy access and the abundance of the species involved.

High-resolution mapping of the S-locus in Turnera leads to the discovery of three genes tightly associated with the S-alleles.

PubMed

Labonne, Jonathan J D; Goultiaeva, Alina; Shore, Joel S

2009-06-01

While the breeding system known as distyly has been used as a model system in genetics, and evolutionary biology for over a century, the genes determining this system remain unknown. To positionally clone genes determining distyly, a high-resolution map of the S-locus region of Turnera has been constructed using segregation data from 2,013 backcross progeny. We discovered three putative genes tightly linked with the S-locus. An N-acetyltransferase (TkNACE) flanks the S-locus at 0.35 cM while a sulfotransferase (TkST1) and a non-LTR retroelement (TsRETRO) show complete linkage to the S-locus. An assay of population samples of six species revealed that TsRETRO, initially discovered in diploid Turnera subulata, is also associated with the S-allele in tetraploid T. subulata and diploid Turnera scabra. The sulfotransferase gene shows some level of differential expression in long versus short styles, indicating it might be involved in some aspect of distyly. The complete linkage of TkST1 and TsRETRO to the S-locus suggests that both genes may reside within, or in the immediate vicinity of the S-locus. Chromosome walking has been initiated using one of the genes discovered in the present study to identify the genes determining distyly.

Candidate Genes Expressed in Tolerant Common Wheat With Resistant to English Grain Aphid.

PubMed

Luo, Kun; Zhang, Gaisheng; Wang, Chunping; Ouellet, Thérèse; Wu, Jingjing; Zhu, Qidi; Zhao, Huiyan

2014-10-01

The English grain aphid, Sitobion avenae (F.) (Hemiptera: Aphididae), is a common worldwide pest of wheat (Triticum aestivum L.). The use of improved resistant cultivars by the farmers is the most effective and environmentally friendly method to control this aphid in the field. The winter wheat genotypes 98-10-35 and Amigo are resistant to S. avenae. To identify genes responsible for resistance to S. avenae in these genotypes, differential-display reverse transcription-polymerase chain reaction was used to identify the corresponding differentially expressed sequences in current study. Two backcross progenies were obtained by crossing the two resistant genotypes with the susceptible genotype 1376. Six potential expected-differential bands were sequenced. Lengths of the expressed sequence tags ranged from 128 to 532 bp. Although these expressed sequences were likely associated with S. avenae resistance, there was one expressed sequence tag located on 7DL chromosome, and its potential function may associate with the ability to maintain photosynthesis in wheat. That serves as an active way for tolerant common wheat with resistant to S. avenae. Cloning the full length of these sequences would help us thoroughly understand the mechanism of wheat resistance to S. avenae and be valuable for breeding cultivars with S. avenae resistance. © 2014 Entomological Society of America.

Inheritance of resistance to watermelon mosaic virus in the cucumber line TMG-1: tissue-specific expression and relationship to zucchini yellow mosaic virus resistance.

PubMed

Wai, T; Grumet, R

1995-09-01

The inbred cucumber (Cucumis sativus L.) line TMG-1 is resistant to three potyviruses:zucchini yellow mosaic virus (ZYMV), watermelon mosaic virus (WMV), and the watermelon strain of papaya ringspot virus (PRSV-W). The genetics of resistance to WMV and the relationship of WMV resistance to ZYMV resistance were examined. TMG-1 was crossed with WI-2757, a susceptible inbred line. F1, F2 and backcross progeny populations were screened for resistance to WMV and/or ZYMV. Two independently assorting factors conferred resistance to WMV. One resistance was conferred by a single recessive gene from TMG-1 (wmv-2). The second resistance was conferred by an epistatic interaction between a second recessive gene from TMG-1 (wmv-3) and either a dominant gene from WI-2757 (Wmv-4) or a third recessive gene from TMG-1 (wmv-4) located 20-30 cM from wmv-3. The two resistances exhibited tissue-specific expression. Resistance conferred by wmv-2 was expressed in the cotyledons and throughout the plant. Resistance conferred by wmv-3 + Wmv-4 (or wmv-4) was expressed only in true leaves. The gene conferring resistance to ZYMV appeared to be the same as, or tightly linked to one of the WMV resistance genes, wmv-3.

Multiple loci and genetic interactions involving flowering time genes regulate stem branching among natural variants of Arabidopsis.

PubMed

Huang, Xueqing; Ding, Jia; Effgen, Sigi; Turck, Franziska; Koornneef, Maarten

2013-08-01

Shoot branching is a major determinant of plant architecture. Genetic variants for reduced stem branching in the axils of cauline leaves of Arabidopsis were found in some natural accessions and also at low frequency in the progeny of multiparent crosses. Detailed genetic analysis using segregating populations derived from backcrosses with the parental lines and bulked segregant analysis was used to identify the allelic variation controlling reduced stem branching. Eight quantitative trait loci (QTLs) contributing to natural variation for reduced stem branching were identified (REDUCED STEM BRANCHING 1-8 (RSB1-8)). Genetic analysis showed that RSB6 and RSB7, corresponding to flowering time genes FLOWERING LOCUS C (FLC) and FRIGIDA (FRI), epistatically regulate stem branching. Furthermore, FLOWERING LOCUS T (FT), which corresponds to RSB8 as demonstrated by fine-mapping, transgenic complementation and expression analysis, caused pleiotropic effects not only on flowering time, but, in the specific background of active FRI and FLC alleles, also on the RSB trait. The consequence of allelic variation only expressed in late-flowering genotypes revealed novel and thus far unsuspected roles of several genes well characterized for their roles in flowering time control. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

Efficient and heritable transformation of Phalaenopsis orchids.

PubMed

Hsing, Hong-Xian; Lin, Yi-Jyun; Tong, Chii-Gong; Li, Min-Jeng; Chen, Yun-Jin; Ko, Swee-Suak

2016-12-01

Phalaenopsis orchid (Phal. orchid) is visually attractive and it is important economic floriculture species. Phal. orchids have many unique biological features. However, investigation of these features and validation on their biological functions are limited due to the lack of an efficient transformation method. We developed a heritable and efficient Agrobacterium- mediated transformation using protocorms derived from tetraploid or diploid Phal. orchids. A T-DNA vector construct containing eGFP driven by ubiquitin promoter was subjected to transformation. An approximate 1.2-5.2 % transformation rate was achieved. Genomic PCR confirmed that hygromycin selection marker, HptII gene and target gene eGFP were integrated into the orchid genome. Southern blotting indicated a low T-DNA insertion number in the orchid genome of the transformants. Western blot confirmed the expression of eGFP protein in the transgenic orchids. Furthermore, the GFP signal was detected in the transgenic orchids under microscopy. After backcrossing the pollinia of the transgenic plants to four different Phal. orchid varieties, the BC1 progenies showed hygromycin resistance and all surviving BC1 seedlings were HptII positive in PCR and expressed GFP protein as shown by western blot. This study demonstrated a stable transformation system was generated for Phal. orchids. This useful transformation protocol enables functional genomics studies and molecular breeding.

Myostatin gene mutated mice induced with tale nucleases.

PubMed

Zhou, Fangfang; Sun, Ruilin; Chen, Hongyan; Fei, Jian; Lu, Daru

2015-01-01

Myostain gene (MSTN) is expressed primarily in skeletal muscle, and negatively regulates skeletal muscle mass; it has been suggested that mice with MSTN inhibition have reduced adiposity and improved insulin sensitivity. Therefore, it is important to establish a fast and effective gene editing method. In this report, we established the myostatin mutated-mouse model by microinjection of Transcription Activator-Like Effector Nucleases (TALENs) mRNA within the mouse fertilized oocytes and achieved high rates of mutagenesis of the mouse MSTN in C57BL/6J. Six of 45 born mice carried target mutations and we appointed one as the parental mating with wild mouse to produce the F1 and backcross to produce the F2 generation. All the mutations of the mice were examined quickly and efficiently by high-resolution melting curve analysis (HRMA) and then verified by direct sequencing. We obtained the homozygous of the F2 generation which transmitted the mutant alleles to the progeny with 100% efficiency. Mutant mice exhibited increases in muscle mass comparable to those observed in wild-type mice. Therefore, combining TALEN-mediated gene targeting with HRMA technology is a superior method of constructing genetically modified mice through microinjection in the mouse fertilized oocytes with high efficiency and short time of selection.

Parental identity influences progeny responses to incubation thermal stress in sockeye salmon Onchorhynchus nerka.

PubMed

Burt, J M; Hinch, S G; Patterson, D A

2012-02-01

The influence of individual parentage on progeny responses to early developmental temperature stress was examined in a cross-fertilization experiment using sockeye salmon Oncorhynchus nerka. Differences in survival, hatch timing and size were examined among five paternally linked and five maternally linked offspring families (Weaver Creek population, British Columbia, Canada) incubated at 12, 14 and 16° C from just after fertilization to hatch. Mean embryonic survival was significantly lower at 14 and 16° C; however, offspring families had substantially different survival responses across the thermal gradient (crossing reaction norms). Within temperature treatments, substantial variation in embryonic survival, alevin mass, time-to-hatch and hatch duration were attributable to family identity; however, most traits were governed by significant temperature-family interactions. For embryonic survival, large differences between families at 16° C were due to both female and male spawner influence, whereas inter-family differences were obscured at 14° C (high intra-family variation), and minimal at 12° C (only maternal influence detected). Despite post-hatch rearing under a common cool thermal regime, persistent effects of both temperature and parentage were detected in alevin and 3 week-old fry. Collectively, these findings highlight the crucial role that parental influences on offspring may have in shaping future selection within salmonid populations exposed to elevated thermal regimes. An increased understanding of parental and temperature influences and their persistence in early development will be essential to developing a more comprehensive view of population spawning success and determining the adaptive capacity of O. nerka populations in the face of environmental change. © 2011 The Authors. Journal of Fish Biology © 2011 The Fisheries Society of the British Isles.

Maternal caloric restriction partially rescues the deleterious effects of advanced maternal age on offspring

PubMed Central

Gribble, Kristin E; Jarvis, George; Bock, Martha; Mark Welch, David B

2014-01-01

While many studies have focused on the detrimental effects of advanced maternal age and harmful prenatal environments on progeny, little is known about the role of beneficial non-Mendelian maternal inheritance on aging. Here, we report the effects of maternal age and maternal caloric restriction (CR) on the life span and health span of offspring for a clonal culture of the monogonont rotifer Brachionus manjavacas. Mothers on regimens of chronic CR (CCR) or intermittent fasting (IF) had increased life span compared with mothers fed ad libitum (AL). With increasing maternal age, life span and fecundity of female offspring of AL-fed mothers decreased significantly and life span of male offspring was unchanged, whereas body size of both male and female offspring increased. Maternal CR partially rescued these effects, increasing the mean life span of AL-fed female offspring but not male offspring and increasing the fecundity of AL-fed female offspring compared with offspring of mothers of the same age. Both maternal CR regimens decreased male offspring body size, but only maternal IF decreased body size of female offspring, whereas maternal CCR caused a slight increase. Understanding the genetic and biochemical basis of these different maternal effects on aging may guide effective interventions to improve health span and life span. PMID:24661622

Risk assessment of genetically engineered crops: fitness effects of virus-resistance transgenes in wild Cucurbita pepo.

PubMed

Laughlin, Karen D; Power, Alison G; Snow, Allison A; Spencer, Lawrence J

2009-07-01

The development of crops genetically engineered for pathogen resistance has raised concerns that crop-to-wild gene flow could release wild or weedy relatives from regulation by the pathogens targeted by the transgenes that confer resistance. Investigation of these risks has also raised questions about the impact of gene flow from conventional crops into wild plant populations. Viruses in natural plant populations can play important roles in plant fecundity and competitive interactions. Here, we show that virus-resistance transgenes and conventional crop genes can increase fecundity of wild plants under virus pressure. We asked how gene flow from a cultivated squash (Cucurbita pepo) engineered for virus resistance would affect the fecundity of wild squash (C. pepo) in the presence and absence of virus pressure. A transgenic squash cultivar was crossed and backcrossed with wild C. pepo from Arkansas. Wild C. pepo, transgenic backcross plants, and non-transgenic backcross plants were compared in field plots in Ithaca, New York, USA. The second and third generations of backcrosses (BC2 and BC3) were used in 2002 and 2003, respectively. One-half of the plants were inoculated with zucchini yellow mosaic virus (ZYMV), and one-half of the plants were maintained as healthy controls. Virus pressure dramatically decreased the fecundity of wild C. pepo plants and non-transgenic backcross plants relative to transgenic backcross plants, which showed continued functioning of the virus-resistance transgene. In 2002, non-transgenic backcross fecundity was slightly higher than wild C. pepo fecundity under virus pressure, indicating a possible benefit of conventional crop alleles, but they did not differ in 2003 when fecundity was lower in both groups. We detected no fitness costs of the transgene in the absence of the virus. If viruses play a role in the population dynamics of wild C. pepo, we predict that gene flow from transgenic, virus-resistant squash and, to a much lesser

[Progeny of Palmistichus elaeisis Delvare & LaSalle (Hymenoptera: Eulophidae) parasitising pupae of Bombyx mori L. (Lepidoptera: Bombycidae) of different ages].

PubMed

Pereira, Fabricio F; Zanuncio, José C; Serrão, José E; Oliveira, Harley N; Fávero, Kellen; Grance, Elizangela L V

2009-01-01

Palmistichus elaeisis Delvare & LaSalle is a natural pupal parasitoid of eucalyptus defoliator lepidopterans and is considered a promising biocontrol agent. However, the development of efficient rearing techniques for this natural enemy are first required before it can be used in biocontrol programs. Bombyx mori L. pupae are potential alternative hosts for this parasitoid mass rearing, and they are easy to rear. Therefore, we investigated the most suitable host age and the effects of parasitoid age on progeny production of P. elaeisis. B. mori pupae, 24 h-, 48 h-, 72 h- or 96 h-old were exposed to P. elaeisis females of similar age. The duration of the life cycle (egg-adult) of P. elaeisis was not affected by the age of the parasitizing female; however, the host age affected parasitoid development. The best parasitization was obtained for 72 h- to 96 h-old parasitoid females when offered to 48 h- to 72 h-old host pupae, allowing the synchronized rearing of a large number of P. elaeisis offspring.

Transcriptomic Analysis Using Olive Varieties and Breeding Progenies Identifies Candidate Genes Involved in Plant Architecture.

PubMed

González-Plaza, Juan J; Ortiz-Martín, Inmaculada; Muñoz-Mérida, Antonio; García-López, Carmen; Sánchez-Sevilla, José F; Luque, Francisco; Trelles, Oswaldo; Bejarano, Eduardo R; De La Rosa, Raúl; Valpuesta, Victoriano; Beuzón, Carmen R

2016-01-01

Plant architecture is a critical trait in fruit crops that can significantly influence yield, pruning, planting density and harvesting. Little is known about how plant architecture is genetically determined in olive, were most of the existing varieties are traditional with an architecture poorly suited for modern growing and harvesting systems. In the present study, we have carried out microarray analysis of meristematic tissue to compare expression profiles of olive varieties displaying differences in architecture, as well as seedlings from their cross pooled on the basis of their sharing architecture-related phenotypes. The microarray used, previously developed by our group has already been applied to identify candidates genes involved in regulating juvenile to adult transition in the shoot apex of seedlings. Varieties with distinct architecture phenotypes and individuals from segregating progenies displaying opposite architecture features were used to link phenotype to expression. Here, we identify 2252 differentially expressed genes (DEGs) associated to differences in plant architecture. Microarray results were validated by quantitative RT-PCR carried out on genes with functional annotation likely related to plant architecture. Twelve of these genes were further analyzed in individual seedlings of the corresponding pool. We also examined Arabidopsis mutants in putative orthologs of these targeted candidate genes, finding altered architecture for most of them. This supports a functional conservation between species and potential biological relevance of the candidate genes identified. This study is the first to identify genes associated to plant architecture in olive, and the results obtained could be of great help in future programs aimed at selecting phenotypes adapted to modern cultivation practices in this species.

Introgression of wheat DNA markers from A, B and D genomes in early generation progeny of Aegilops cylindrica Host x Triticum aestivum L. hybrids.

PubMed

Schoenenberger, N; Felber, F; Savova-Bianchi, D; Guadagnuolo, R

2005-11-01

Introgression from allohexaploid wheat (Triticum aestivum L., AABBDD) to allotetraploid jointed goatgrass (Aegilops cylindrica Host, CCDD) can take place in areas where the two species grow in sympatry and hybridize. Wheat and Ae. cylindrica share the D genome, issued from the common diploid ancestor Aegilops tauschii Coss. It has been proposed that the A and B genome of bread wheat are secure places to insert transgenes to avoid their introgression into Ae. cylindrica because during meiosis in pentaploid hybrids, A and B genome chromosomes form univalents and tend to be eliminated whereas recombination takes place only in D genome chromosomes. Wheat random amplified polymorphic DNA (RAPD) fragments, detected in intergeneric hybrids and introgressed to the first backcross generation with Ae. cylindrica as the recurrent parent and having a euploid Ae. cylindrica chromosome number or one supernumerary chromosome, were assigned to wheat chromosomes using Chinese Spring nulli-tetrasomic wheat lines. Introgressed fragments were not limited to the D genome of wheat, but specific fragments of A and B genomes were also present in the BC1. Their presence indicates that DNA from any of the wheat genomes can introgress into Ae. cylindrica. Successfully located RAPD fragments were then converted into highly specific and easy-to-use sequence characterised amplified regions (SCARs) through sequencing and primer design. Subsequently these markers were used to characterise introgression of wheat DNA into a BC1S1 family. Implications for risk assessment of genetically modified wheat are discussed.

Human epithelial hair follicle stem cells and their progeny: current state of knowledge, the widening gap in translational research and future challenges.

PubMed

Purba, Talveen S; Haslam, Iain S; Poblet, Enrique; Jiménez, Francisco; Gandarillas, Alberto; Izeta, Ander; Paus, Ralf

2014-05-01

Epithelial hair follicle stem cells (eHFSCs) are required to generate, maintain and renew the continuously cycling hair follicle (HF), supply cells that produce the keratinized hair shaft and aid in the reepithelialization of injured skin. Therefore, their study is biologically and clinically important, from alopecia to carcinogenesis and regenerative medicine. However, human eHFSCs remain ill defined compared to their murine counterparts, and it is unclear which murine eHFSC markers really apply to the human HF. We address this by reviewing current concepts on human eHFSC biology, their immediate progeny and their molecular markers, focusing on Keratin 15 and 19, CD200, CD34, PHLDA1, and EpCAM/Ber-EP4. After delineating how human eHFSCs may be selectively targeted experimentally, we close by defining as yet unmet key challenges in human eHFSC research. The ultimate goal is to transfer emerging concepts from murine epithelial stem cell biology to human HF physiology and pathology. © 2014 WILEY Periodicals, Inc.

Incest versus abstinence: reproductive trade-offs between mate limitation and progeny fitness in a self-incompatible invasive plant

PubMed Central

Pierson, Jennifer C; Swain, Stephen M; Young, Andrew G

2013-01-01

Plant mating systems represent an evolutionary and ecological trade-off between reproductive assurance through selfing and maximizing progeny fitness through outbreeding. However, many plants with sporophytic self-incompatibility systems exhibit dominance interactions at the S-locus that allow biparental inbreeding, thereby facilitating mating between individuals that share alleles at the S-locus. We investigated this trade-off by estimating mate availability and biparental inbreeding depression in wild radish from five different populations across Australia. We found dominance interactions among S-alleles increased mate availability relative to estimates based on individuals that did not share S-alleles. Twelve of the sixteen fitness variables were significantly reduced by inbreeding. For all the three life-history phases evaluated, self-fertilized offspring suffered a greater than 50% reduction in fitness, while full-sib and half-sib offspring suffered a less than 50% reduction in fitness. Theory indicates that fitness costs greater than 50% can result in an evolutionary trajectory toward a stable state of self-incompatibility (SI). This study suggests that dominance interactions at the S-locus provide a possible third stable state between SI and SC where biparental inbreeding increases mate availability with relatively minor fitness costs. This strategy allows weeds to establish in new environments while maintaining a functional SI system. PMID:24455137

Incest versus abstinence: reproductive trade-offs between mate limitation and progeny fitness in a self-incompatible invasive plant.

PubMed

Pierson, Jennifer C; Swain, Stephen M; Young, Andrew G

2013-12-01

Plant mating systems represent an evolutionary and ecological trade-off between reproductive assurance through selfing and maximizing progeny fitness through outbreeding. However, many plants with sporophytic self-incompatibility systems exhibit dominance interactions at the S-locus that allow biparental inbreeding, thereby facilitating mating between individuals that share alleles at the S-locus. We investigated this trade-off by estimating mate availability and biparental inbreeding depression in wild radish from five different populations across Australia. We found dominance interactions among S-alleles increased mate availability relative to estimates based on individuals that did not share S-alleles. Twelve of the sixteen fitness variables were significantly reduced by inbreeding. For all the three life-history phases evaluated, self-fertilized offspring suffered a greater than 50% reduction in fitness, while full-sib and half-sib offspring suffered a less than 50% reduction in fitness. Theory indicates that fitness costs greater than 50% can result in an evolutionary trajectory toward a stable state of self-incompatibility (SI). This study suggests that dominance interactions at the S-locus provide a possible third stable state between SI and SC where biparental inbreeding increases mate availability with relatively minor fitness costs. This strategy allows weeds to establish in new environments while maintaining a functional SI system.

Selecting elephant grass families and progenies to produce bioenergy through mixed models (REML/BLUP).

PubMed

Rodrigues, E V; Daher, R F; Dos Santos, A; Vivas, M; Machado, J C; Gravina, G do A; de Souza, Y P; Vidal, A K; Rocha, A Dos S; Freitas, R S

2017-05-18

Brazil has great potential to produce bioenergy since it is located in a tropical region that receives high incidence of solar energy and presents favorable climatic conditions for such purpose. However, the use of bioenergy in the country is below its productivity potential. The aim of the current study was to select full-sib progenies and families of elephant grass (Pennisetum purpureum S.) to optimize phenotypes relevant to bioenergy production through mixed models (REML/BLUP). The circulating diallel-based crossing of ten elephant grass genotypes was performed. An experimental design using the randomized block methodology, with three repetitions, was set to assess both the hybrids and the parents. Each plot comprised 14-m rows, 1.40 m spacing between rows, and 1.40 m spacing between plants. The number of tillers, plant height, culm diameter, fresh biomass production, dry biomass rate, and the dry biomass production were assessed. Genetic-statistical analyses were performed through mixed models (REML/BLUP). The genetic variance in the assessed families was explained through additive genetic effects and dominance genetic effects; the dominance variance was prevalent. Families such as Capim Cana D'África x Guaçu/I.Z.2, Cameroon x Cuba-115, CPAC x Cuba-115, Cameroon x Guaçu/I.Z.2, and IAC-Campinas x CPAC showed the highest dry biomass production. The family derived from the crossing between Cana D'África and Guaçu/I.Z.2 showed the largest number of potential individuals for traits such as plant height, culm diameter, fresh biomass production, dry biomass production, and dry biomass rate. The individual 5 in the family Cana D'África x Guaçu/I.Z.2, planted in blocks 1 and 2, showed the highest dry biomass production.

EFFECTS OF DIFFERENT LEVELS OF INBREEDING ON PROGENY FITNESS IN PLANTAGO CORONOPUS.

PubMed

Koelewijn, Hans Peter

1998-06-01

Inbreeding depression (δ) is a major selective force favoring outcrossing in flowering plants. Many phenotypic and genetic models of the evolution of selfing conclude that complete outcrossing should evolve whenever inbreeding depression is greater than one-half, otherwise selfing should evolve. Recent theoretical work, however, has challenged this view and emphasized (1) the importance of variation in inbreeding depression among individuals within a population; and (2) the nature of gene action between deleterious mutations at different loci (epistasis) as important determinants for the evolution of plant mating systems. The focus of this study was to examine the maintenance of inbreeding depression and the relationship between inbreeding level and inbreeding depression at both the population and the individual level in one population of the partially self-fertilizing plant Plantago coronopus (L.). Maternal plants, randomly selected from an area of about 50 m 2 in a natural population, were used to establish lines with expected inbreeding coefficients (f) of 0, 0.25, 0.50, 0.75, and 0.875. Inbreeding depression was estimated both in the greenhouse and at the site of origin of the maternal plants by comparing growth, survival, flowering, and seed production of the progeny with different inbreeding coefficients. No significant inbreeding depression for these fitness traits was detected in the greenhouse after 16 weeks. This was in strong contrast to the field, where the traits all displayed significant inbreeding depression and declined with increased inbreeding. The results were consistent with the view that mutation to mildly deleterious alleles is the primary cause of inbreeding depression. At the family level, significantly different maternal line responses (maternal parent × inbreeding level interaction) provide a mechanism for the invasion of a selfing variant into the population through any maternal line exhibiting purging of its genetic load. At the

Power of a Labrador Retriever-Greyhound pedigree for linkage analysis of hip dysplasia and osteoarthritis.

PubMed

Todhunter, Rory J; Casella, George; Bliss, Stuart P; Lust, George; Williams, Alma Jo; Hamilton, Samuel; Dykes, Nathan L; Yeager, Amy E; Gilbert, Robert O; Burton-Wurster, Nancy I; Mellersh, Cathryn C; Acland, Gregory M

2003-04-01

To estimate the number of dogs required to find linkage to heritable traits of hip dysplasia in dogs from an experimental pedigree. 147 Labrador Retrievers, Greyhounds, and their crossbreed offspring. Labrador Retrievers with hip dysplasia were crossed with unaffected Greyhounds. Age at detection of femoral capital ossification, distraction index (DI), hip joint dorsolateral subluxation (DLS) score, and hip joint osteoarthritis (OA) were recorded. Power to find linkage of a single marker to a quantitative trait locus (QTL) controlling 100% of the variation in a dysplastic trait in the backcross dogs was determined. For the DI at the observed effect size, recombination fraction of 0.05, and heterozygosity of 0.75, 35 dogs in the backcross of the F1 to the Greyhound generation would yield linkage at a power of 0.8. For the DLS score, 35 dogs in the backcross to the Labrador Retriever generation would be required for linkage at the same power. For OSS, 45 dogs in the backcross to the founding Labrador Retrievers would yield linkage at the same power. Fewer dogs were projected to be necessary to find linkage to hip OA. Testing for linkage to the DLS at 4 loci simultaneously, each controlling 25% of the phenotypic variation, yielded an overall power of 0.7 CONCLUSIONS AND CLINICAL SIGNIFICANCE: Based on this conservative single-marker estimate, this pedigree has the requisite power to find microsatellites linked to susceptibility loci for hip dysplasia and hip OA by breeding a reasonable number of backcross dogs.

Transcriptomic Analysis Using Olive Varieties and Breeding Progenies Identifies Candidate Genes Involved in Plant Architecture

PubMed Central

González-Plaza, Juan J.; Ortiz-Martín, Inmaculada; Muñoz-Mérida, Antonio; García-López, Carmen; Sánchez-Sevilla, José F.; Luque, Francisco; Trelles, Oswaldo; Bejarano, Eduardo R.; De La Rosa, Raúl; Valpuesta, Victoriano; Beuzón, Carmen R.

2016-01-01

Plant architecture is a critical trait in fruit crops that can significantly influence yield, pruning, planting density and harvesting. Little is known about how plant architecture is genetically determined in olive, were most of the existing varieties are traditional with an architecture poorly suited for modern growing and harvesting systems. In the present study, we have carried out microarray analysis of meristematic tissue to compare expression profiles of olive varieties displaying differences in architecture, as well as seedlings from their cross pooled on the basis of their sharing architecture-related phenotypes. The microarray used, previously developed by our group has already been applied to identify candidates genes involved in regulating juvenile to adult transition in the shoot apex of seedlings. Varieties with distinct architecture phenotypes and individuals from segregating progenies displaying opposite architecture features were used to link phenotype to expression. Here, we identify 2252 differentially expressed genes (DEGs) associated to differences in plant architecture. Microarray results were validated by quantitative RT-PCR carried out on genes with functional annotation likely related to plant architecture. Twelve of these genes were further analyzed in individual seedlings of the corresponding pool. We also examined Arabidopsis mutants in putative orthologs of these targeted candidate genes, finding altered architecture for most of them. This supports a functional conservation between species and potential biological relevance of the candidate genes identified. This study is the first to identify genes associated to plant architecture in olive, and the results obtained could be of great help in future programs aimed at selecting phenotypes adapted to modern cultivation practices in this species. PMID:26973682

Effect on radioactivity concentration estimation of radon progenies with NaI(Tl) pulse height distribution from considering geometric structure around detector and infiltration of radionuclides.

PubMed

Hirouchi, J; Terasaka, Y; Hirao, S; Moriizumi, J; Yamazawa, H

2015-11-01

The surface radioactivity concentrations of the radon progenies, (214)Pb and (214)Bi, were estimated from NaI(Tl) pulse height distributions during rain. The improvement in estimation errors caused by considering geometric structures around measuring points and infiltration of radionuclides was discussed. The surface radioactivity concentrations were determined by comparing the count rates at the full-energy peak ranges between observation and calculation with the electron-photon transport code EGS5. It was shown that the concentrations can be underestimated by about 30 % unless the obstacles around the detector or infiltration of radionuclides are considered in gamma ray transfer calculations at measuring points, where there are many tall obstacles, or the ground is covered with unpaved areas. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Floral-Dip Transformation of Flax (Linum usitatissimum) to Generate Transgenic Progenies with a High Transformation Rate

PubMed Central

Bastaki, Nasmah K.; Cullis, Christopher A.

2014-01-01

Agrobacterium-mediated plant transformation via floral-dip is a widely used technique in the field of plant transformation and has been reported to be successful for many plant species. However, flax (Linum usitatissimum) transformation by floral-dip has not been reported. The goal of this protocol is to establish that Agrobacterium and the floral-dip method can be used to generate transgenic flax. We show that this technique is simple, inexpensive, efficient, and more importantly, gives a higher transformation rate than the current available methods of flax transformation. In summary, inflorescences of flax were dipped in a solution of Agrobacterium carrying a binary vector plasmid (T-DNA fragment plus the Linum Insertion Sequence, LIS-1) for 1 - 2 min. The plants were laid flat on their side for 24 hr. Then, plants were maintained under normal growth conditions until the next treatment. The process of dipping was repeated 2 - 3 times, with approximately 10 - 14 day intervals between dipping. The T1 seeds were collected and germinated on soil. After approximately two weeks, treated progenies were tested by direct PCR; 2 - 3 leaves were used per plant plus the appropriate T-DNA primers. Positive transformants were selected and grown to maturity. The transformation rate was unexpectedly high, with 50 - 60% of the seeds from treated plants being positive transformants. This is a higher transformation rate than those reported for Arabidopsis thaliana and other plant species, using floral-dip transformation. It is also the highest, which has been reported so far, for flax transformation using other methods for transformation. PMID:25549243

Floral-dip transformation of flax (Linum usitatissimum) to generate transgenic progenies with a high transformation rate.

PubMed

Bastaki, Nasmah K; Cullis, Christopher A

2014-12-19

Agrobacterium-mediated plant transformation via floral-dip is a widely used technique in the field of plant transformation and has been reported to be successful for many plant species. However, flax (Linum usitatissimum) transformation by floral-dip has not been reported. The goal of this protocol is to establish that Agrobacterium and the floral-dip method can be used to generate transgenic flax. We show that this technique is simple, inexpensive, efficient, and more importantly, gives a higher transformation rate than the current available methods of flax transformation. In summary, inflorescences of flax were dipped in a solution of Agrobacterium carrying a binary vector plasmid (T-DNA fragment plus the Linum Insertion Sequence, LIS-1) for 1 - 2 min. The plants were laid flat on their side for 24 hr. Then, plants were maintained under normal growth conditions until the next treatment. The process of dipping was repeated 2 - 3 times, with approximately 10 - 14 day intervals between dipping. The T1 seeds were collected and germinated on soil. After approximately two weeks, treated progenies were tested by direct PCR; 2 - 3 leaves were used per plant plus the appropriate T-DNA primers. Positive transformants were selected and grown to maturity. The transformation rate was unexpectedly high, with 50 - 60% of the seeds from treated plants being positive transformants. This is a higher transformation rate than those reported for Arabidopsis thaliana and other plant species, using floral-dip transformation. It is also the highest, which has been reported so far, for flax transformation using other methods for transformation.

Recombinants from the crosses between amphidiploid and cultivated peanut (Arachis hypogaea) for pest-resistance breeding programs.

PubMed

de Paula, Ailton Ferreira; Dinato, Naiana Barbosa; Vigna, Bianca Baccili Zanotto; Fávero, Alessandra Pereira

2017-01-01

Peanut is a major oilseed crop worldwide. In the Brazilian peanut production, silvering thrips and red necked peanut worm are the most threatening pests. Resistant varieties are considered an alternative to pest control. Many wild diploid Arachis species have shown resistance to these pests, and these can be used in peanut breeding by obtaining hybrid of A and B genomes and subsequent polyploidization with colchicine, resulting in an AABB amphidiploid. This amphidiploid can be crossed with cultivated peanut (AABB) to provide genes of interest to the cultivar. In this study, the sterile diploid hybrids from A. magna V 13751 and A. kempff-mercadoi V 13250 were treated with colchicine for polyploidization, and the amphidiploids were crossed with A. hypogaea cv. IAC OL 4 to initiate the introgression of the wild genes into the cultivated peanut. The confirmation of the hybridity of the progenies was obtained by: (1) reproductive characterization through viability of pollen, (2) molecular characterization using microsatellite markers and (3) morphological characterization using 61 morphological traits with principal component analysis. The diploid hybrid individual was polyploidized, generating the amphidiploid An 13 (A. magna V 13751 x A. kempff-mercadoi V 13250)4x. Four F1 hybrid plants were obtained from IAC OL 4 × An 13, and 51 F2 seeds were obtained from these F1 plants. Using reproductive, molecular and morphological characterizations, it was possible to distinguish hybrid plants from selfed plants. In the cross between A. hypogaea and the amphidiploid, as the two parents are polyploid, the hybrid progeny and selves had the viability of the pollen grains as high as the parents. This fact turns the use of reproductive characteristics impossible for discriminating, in this case, the hybrid individuals from selfing. The hybrids between A. hypogaea and An 13 will be used in breeding programs seeking pest resistance, being subjected to successive backcrosses until

Recombinants from the crosses between amphidiploid and cultivated peanut (Arachis hypogaea) for pest-resistance breeding programs

PubMed Central

de Paula, Ailton Ferreira; Dinato, Naiana Barbosa

2017-01-01

Peanut is a major oilseed crop worldwide. In the Brazilian peanut production, silvering thrips and red necked peanut worm are the most threatening pests. Resistant varieties are considered an alternative to pest control. Many wild diploid Arachis species have shown resistance to these pests, and these can be used in peanut breeding by obtaining hybrid of A and B genomes and subsequent polyploidization with colchicine, resulting in an AABB amphidiploid. This amphidiploid can be crossed with cultivated peanut (AABB) to provide genes of interest to the cultivar. In this study, the sterile diploid hybrids from A. magna V 13751 and A. kempff-mercadoi V 13250 were treated with colchicine for polyploidization, and the amphidiploids were crossed with A. hypogaea cv. IAC OL 4 to initiate the introgression of the wild genes into the cultivated peanut. The confirmation of the hybridity of the progenies was obtained by: (1) reproductive characterization through viability of pollen, (2) molecular characterization using microsatellite markers and (3) morphological characterization using 61 morphological traits with principal component analysis. The diploid hybrid individual was polyploidized, generating the amphidiploid An 13 (A. magna V 13751 x A. kempff-mercadoi V 13250)4x. Four F1 hybrid plants were obtained from IAC OL 4 × An 13, and 51 F2 seeds were obtained from these F1 plants. Using reproductive, molecular and morphological characterizations, it was possible to distinguish hybrid plants from selfed plants. In the cross between A. hypogaea and the amphidiploid, as the two parents are polyploid, the hybrid progeny and selves had the viability of the pollen grains as high as the parents. This fact turns the use of reproductive characteristics impossible for discriminating, in this case, the hybrid individuals from selfing. The hybrids between A. hypogaea and An 13 will be used in breeding programs seeking pest resistance, being subjected to successive backcrosses until

Maternal caloric restriction partially rescues the deleterious effects of advanced maternal age on offspring.

PubMed

Gribble, Kristin E; Jarvis, George; Bock, Martha; Mark Welch, David B

2014-08-01

While many studies have focused on the detrimental effects of advanced maternal age and harmful prenatal environments on progeny, little is known about the role of beneficial non-Mendelian maternal inheritance on aging. Here, we report the effects of maternal age and maternal caloric restriction (CR) on the life span and health span of offspring for a clonal culture of the monogonont rotifer Brachionus manjavacas. Mothers on regimens of chronic CR (CCR) or intermittent fasting (IF) had increased life span compared with mothers fed ad libitum (AL). With increasing maternal age, life span and fecundity of female offspring of AL-fed mothers decreased significantly and life span of male offspring was unchanged, whereas body size of both male and female offspring increased. Maternal CR partially rescued these effects, increasing the mean life span of AL-fed female offspring but not male offspring and increasing the fecundity of AL-fed female offspring compared with offspring of mothers of the same age. Both maternal CR regimens decreased male offspring body size, but only maternal IF decreased body size of female offspring, whereas maternal CCR caused a slight increase. Understanding the genetic and biochemical basis of these different maternal effects on aging may guide effective interventions to improve health span and life span. © 2014 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

Identification and fine-mapping of Xa33, a novel gene for resistance to Xanthomonas oryzae pv. oryzae.

PubMed

Kumar, P Natraj; Sujatha, K; Laha, G S; Rao, K Srinivasa; Mishra, B; Viraktamath, B C; Hari, Y; Reddy, C S; Balachandran, S M; Ram, T; Madhav, M Sheshu; Rani, N Shobha; Neeraja, C N; Reddy, G Ashok; Shaik, H; Sundaram, R M

2012-02-01

Broadening of the genetic base for identification and transfer of genes for resistance to insect pests and diseases from wild relatives of rice is an important strategy in resistance breeding programs across the world. An accession of Oryza nivara, International Rice Germplasm Collection (IRGC) accession number 105710, was identified to exhibit high level and broad-spectrum resistance to Xanthomonas oryzae pv. oryzae. In order to study the genetics of resistance and to tag and map the resistance gene or genes present in IRGC 105710, it was crossed with the bacterial blight (BB)-susceptible varieties 'TN1' and 'Samba Mahsuri' (SM) and then backcrossed to generate backcross mapping populations. Analysis of these populations and their progeny testing revealed that a single dominant gene controls resistance in IRGC 105710. The BC(1)F(2) population derived from the cross IRGC 105710/TN1//TN1 was screened with a set of 72 polymorphic simple-sequence repeat (SSR) markers distributed across the rice genome and the resistance gene was coarse mapped on chromosome 7 between the SSR markers RM5711 and RM6728 at a genetic distance of 17.0 and 19.3 centimorgans (cM), respectively. After analysis involving 49 SSR markers located between the genomic interval spanned by RM5711 and RM6728, and BC(2)F(2) population consisting of 2,011 individuals derived from the cross IRGC 105710/TN1//TN1, the gene was fine mapped between two SSR markers (RMWR7.1 and RMWR7.6) located at a genetic distance of 0.9 and 1.2 cM, respectively, from the gene and flanking it. The linkage distances were validated in a BC(1)F(2) mapping population derived from the cross IRGC 105710/SM//2 × SM. The BB resistance gene present in the O. nivara accession was identified to be novel based on its unique map location on chromosome 7 and wider spectrum of BB resistance; this gene has been named Xa33. The genomic region between the two closely flanking SSR markers was in silico analyzed for putatively expressed

Evidence of a major gene influencing hair length and heat tolerance in Bos taurus cattle.

PubMed

Olson, T A; Lucena, C; Chase, C C; Hammond, A C

2003-01-01

Evidence was found that supports the existence of a major gene (designated as the slick hair gene), dominant in mode of inheritance, that is responsible for producing a very short, sleek hair coat. Cattle with slick hair were observed to maintain lower rectal temperatures (RT). The gene is found in Senepol cattle and criollo (Spanish origin) breeds in Central and South America. This gene is also found in a Venezuelan composite breed, the Carora, formed from the Brown Swiss and a Venezuelan criollo breed. Two sets of backcross matings of normal-haired sire breeds to Senepol crossbred dams assumed to be heterozygous for the slick hair gene resulted in ratios of slick to normal-haired progeny that did not significantly differ from 1:1. Data from Carora x Holstein crossbred cows in Venezuela also support the concept of a major gene that is responsible for the slick hair coat of the Carora breed. Cows that were 75% Holstein: 25% Carora in breed composition segregated with a ratio that did not differ from 1:1, as would be expected from a backcross matinginvolving a dominant gene. The effect of the slick hair gene on RT depended on the degree of heat stress and appeared to be affected by age and/or lactation status. The decreased RT observed for slick-haired crossbred calves compared to normal-haired contemporaries ranged from 0.18 to 0.4 degrees C. An even larger decrease in RT (0.61 degrees C; P < 0.01) was observed in lactating Carora x Holstein F1 crossbred cows, even though it did not appear that these cows were under severe heat stress. The improved thermotolerance of crossbred calves due to their slick hair coats did not result in increased weaning weights, possibly because both the slick and normal-haired calves were being nursed by slick-haired dams. There were indications that the slick-haired calves grew faster immediately following weaning and that their growth during the cooler months of the year was not compromised significantly by their reduced quantity of

Comparative analysis of the genetic basis of Cry1F resistance in two strains of Spodoptera frugiperda originated from Puerto Rico and Florida.

PubMed

Camargo, Ana M; Castañera, Pedro; Farinós, Gema P; Huang, Fangneng

2017-06-01

The fall armyworm, Spodoptera frugiperda (J.E. Smith), is a major target pest of Bacillus thuringiensis (Bt) maize and cotton in America. Since the commercialization of Cry1F maize (event TC1507) in 2003, resistance to Cry1F maize in field populations of S. frugiperda has occurred in Puerto Rico, Brazil and the southeast region of the United States. In this paper, we conducted a comparative analysis of the inheritance of two Cry1F-resistant colonies of S. frugiperda originated from Puerto Rico (PR) and Florida (FL), respectively. The objective of the analysis was to determine if the genetic basis of the resistance was similar in the two different originated colonies. To accomplish the objective, besides PR, FL, and a known Cry1F-susceptible colony, 14 additional colonies were developed by reciprocal crosses among the three parents, F 1 by F 1 crosses, backcrosses, and intercolony-crosses between PR and FL. Larval mortalities of the 17 colonies were assayed on both Cry1F maize leaf tissue and Cry1F-treated diet at the concentrations of 3.16, 10.00, and 31.60µg/g. Resistance to Cry1F in both PR and FL was autosomal and recessive or incompletely recessive. Segregations in F 2 and backcrossed generations associated with FL fitted the Mendelian monogenic model well, while with PR the segregations did not follow the single gene model in some bioassays. Further analyses with the intercolony complementation tests showed a similar level of resistance in the F 1 progeny as their parents FL and PR. Together with the data, it was likely that a single (or a few tightly-linked) gene was involved in FL; PR shared the same locus of the major resistance gene as FL, but the resistance in PR might also be associated with additional minor factors. Information generated from this study should be useful in understanding the origin of Cry1F resistance in the U.S. mainland and developing effective strategies for Bt resistance management in S. frugiperda. Copyright © 2017 Elsevier Inc

Estimation of in situ mating systems in wild sorghum (Sorghum bicolor (L.) Moench) in Ethiopia using SSR-based progeny array data: implications for the spread of crop genes into the wild.

PubMed

Adugna, Asfaw; Sweeney, Patty M; Bekele, Endashaw

2013-04-01

Because transgenic sorghum (Sorghum bicolor L.) is being developed for Africa, we investigated the potential for transgenes to spread to conspecific wild/weedy sorghum populations in Ethiopia, which is considered the centre of origin of cultivated sorghum. In the current study, the extent of outcrossing, and uniparental and biparental inbreeding were investigated in seven wild/weedy sorghum populations collected at elevations ranging from 631 to 1709 m. Based on allele frequency data of 1120 progenies and 140 maternal plants from five polymorphic microsatellite markers, outcrossing rates were estimated using standard procedures. The average multilocus outcrossing rate was 0.51, with a range of 0.31-0.65 among populations, and the family outcrossing rate was in the extreme range of 0 to 100%. The highest outcrossing (t(m) = 0.65) was recorded in a weedy population that was intermixed with an improved crop variety in Abuare (Wello region). It was also observed that the inbreeding coefficient of the progenies (F(p)) tend to be more than the inbreeding coefficient of both their maternal parents (F(m)) and the level of inbreeding expected at equilibrium (F(eq)), which is a characteristic of predominantly outbreeding species. Biparental inbreeding was evident in all populations and averaged 0.24 (range = 0.10-0.33). The high outcrossing rates of wild/weedy sorghum populations in Ethiopia indicate a high potential for crop genes (including transgenes) to spread within the wild pool. Therefore, effective risk management strategies may be needed if the introgression of transgenes or other crop genes from improved cultivars into wild or weedy populations is deemed to be undesirable.

Advanced Backcross QTL Analysis of Fiber Strength and Fineness in a Cross between Gossypium hirsutum and G. mustelinum.

PubMed

Wang, Baohua; Zhuang, Zhimin; Zhang, Zhengsheng; Draye, Xavier; Shuang, Lan-Shuan; Shehzad, Tariq; Lubbers, Edward L; Jones, Don; May, O Lloyd; Paterson, Andrew H; Chee, Peng W

2017-01-01

The molecular genetic basis of cotton fiber strength and fineness in crosses between Gossypium mustelinum and Gossypium hirsutum (Upland cotton) was dissected using 21 BC 3 F 2 and 12 corresponding BC 3 F 2:3 and BC 3 F 2:4 families. The BC 3 F 2 families were genotyped with simple sequence repeat markers from a G. hirsutum by G. mustelinum linkage map, and the three generations of BC 3 -derived families were phenotyped for fiber strength (STR) and fineness (Micronaire, MIC). A total of 42 quantitative trait loci (QTLs) were identified through one-way analysis of variance, including 15 QTLs for STR and 27 for MIC, with the percentage of variance explained by individual loci averaging 13.86 and 14.06%, respectively. Eighteen of the 42 QTLs were detected at least twice near the same markers in different generations/families or near linked markers in the same family, and 28 of the 42 QTLs were identified in both mixed model-based composite interval mapping and one-way variance analyses. Alleles from G. mustelinum increased STR for eight of 15 and reduced MIC for 15 of 27 QTLs. Significant among-family genotypic effects ( P < 0.001) were detected in 13 and 10 loci for STR and MIC respectively, and five loci showed significant ( P < 0.001) genotype × family interaction for MIC. These results support the hypothesis that fiber quality improvement for Upland cotton could be realized by introgressing G. mustelinum alleles although complexities due to the different effects of genetic background on introgressed chromatin might be faced. Building on prior work with G. barbadense, G. tomentosum , and G. darwinii , QTL mapping involving introgression of G. mustelinum alleles offers new allelic variation to Upland cotton germplasm.

The role of triploids in the origin and evolution of polyploids of Turnera sidoides complex (Passifloraceae, Turneroideae).

PubMed

Kovalsky, I Evelin; Roggero Luque, Juan M; Elías, Gabriela; Fernández, Silvia A; Solís Neffa, Viviana G

2018-01-01

Triploids can play an important role in polyploid evolution. However, their frequent sterility is an obstacle for the origin and establishment of neotetraploids. Here we analyzed the microsporogenesis of triploids (x = 7) and the crossability among cytotypes of Turnera sidoides, aiming to test the impact of triploids on the origin and demographic establishment of tetraploids in natural populations. Triploids of T. sidoides exhibit irregular meiotic behavior. The high frequency of monovalents and of trivalents with non-convergent orientations results in unbalanced and/or non-viable male gametes. In spite of abnormalities in chromosome pairing and unbalanced chromosome segregation, triploids are not completely sterile and yielded up to 67% of viable pollen. Triploids that originated by the fusion of 2n × n gametes of the same taxon showed more regular meiotic behavior and higher fertility than triploids from the contact zone of diploids and tetraploids or triploids of hybrid origin. The reproductive isolation of T. sidoides cytotypes of different ploidy level is not strict and the 'triploid block' may be overcome occasionally. Triploids of T. sidoides produce diploid and triploid progeny suggesting that new generations of polyploids could originate from crosses between triploids or from backcrosses with diploids. The capability of T. sidoides to multiply asexually by rhizomes, would enhance the likelihood that a low frequency of neopolyploids can be originated and maintained in natural populations of T. sidoides.

Inheritance of evolved resistance to a novel herbicide (pyroxasulfone).

PubMed

Busi, Roberto; Gaines, Todd A; Vila-Aiub, Martin M; Powles, Stephen B

2014-03-01

Agricultural weeds have rapidly adapted to intensive herbicide selection and resistance to herbicides has evolved within ecological timescales. Yet, the genetic basis of broad-spectrum generalist herbicide resistance is largely unknown. This study aims to determine the genetic control of non-target-site herbicide resistance trait(s) that rapidly evolved under recurrent selection of the novel lipid biosynthesis inhibitor pyroxasulfone in Lolium rigidum. The phenotypic segregation of pyroxasulfone resistance in parental, F1 and back-cross (BC) families was assessed in plants exposed to a gradient of pyroxasulfone doses. The inheritance of resistance to chemically dissimilar herbicides (cross-resistance) was also evaluated. Evolved resistance to the novel selective agent (pyroxasulfone) is explained by Mendelian segregation of one semi-dominant allele incrementally herbicide-selected at higher frequency in the progeny. In BC families, cross-resistance is conferred by an incompletely dominant single major locus. This study confirms that herbicide resistance can rapidly evolve to any novel selective herbicide agents by continuous and repeated herbicide use. The results imply that the combination of herbicide options (rotation, mixtures or combinations) to exploit incomplete dominance can provide acceptable control of broad-spectrum generalist resistance-endowing monogenic traits. Herbicide diversity within a set of integrated management tactics can be one important component to reduce the herbicide selection intensity. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Harnessing Diversity in Wheat to Enhance Grain Yield, Climate Resilience, Disease and Insect Pest Resistance and Nutrition Through Conventional and Modern Breeding Approaches

PubMed Central

Mondal, Suchismita; Rutkoski, Jessica E.; Velu, Govindan; Singh, Pawan K.; Crespo-Herrera, Leonardo A.; Guzmán, Carlos; Bhavani, Sridhar; Lan, Caixia; He, Xinyao; Singh, Ravi P.

2016-01-01

Current trends in population growth and consumption patterns continue to increase the demand for wheat, a key cereal for global food security. Further, multiple abiotic challenges due to climate change and evolving pathogen and pests pose a major concern for increasing wheat production globally. Triticeae species comprising of primary, secondary, and tertiary gene pools represent a rich source of genetic diversity in wheat. The conventional breeding strategies of direct hybridization, backcrossing and selection have successfully introgressed a number of desirable traits associated with grain yield, adaptation to abiotic stresses, disease resistance, and bio-fortification of wheat varieties. However, it is time consuming to incorporate genes conferring tolerance/resistance to multiple stresses in a single wheat variety by conventional approaches due to limitations in screening methods and the lower probabilities of combining desirable alleles. Efforts on developing innovative breeding strategies, novel tools and utilizing genetic diversity for new genes/alleles are essential to improve productivity, reduce vulnerability to diseases and pests and enhance nutritional quality. New technologies of high-throughput phenotyping, genome sequencing and genomic selection are promising approaches to maximize progeny screening and selection to accelerate the genetic gains in breeding more productive varieties. Use of cisgenic techniques to transfer beneficial alleles and their combinations within related species also offer great promise especially to achieve durable rust resistance. PMID:27458472

A Lactuca universal hybridizer, and its use in creation of fertile interspecific somatic hybrids.

PubMed

Chupeau, M C; Maisonneuve, B; Bellec, Y; Chupeau, Y

1994-10-28

A Lactuca sativa cv. Ardente line heterozygous for a gene encoding resistance to kanamycin, a positive and dominant trait, was crossed with cv. Girelle, which is heterozygous for a recessive albinism marker. The resulting seeds yielded 25% albino seedlings, of which 50% were also resistant to kanamycin. Such plantlets (KR, a) grown in vitro were used for preparation of universal hybridizer protoplasts, since green buds that can develop on kanamycin containing-medium should result from fusion with any wild-type protoplast. To test the practicability of this selection scheme, we fused L. sativa KR, a protoplasts with protoplasts derived from various wild Lactuca as well as various other related species. Protoplast-derived cell colonies were selected for resistance to kanamycin at the regeneration stage. Green buds were regenerated after fusion with protoplasts of L. tatarica and of L. perennis. So far, 9 interspecific hybrid plants have been characterized morphologically. In addition, random amplified polymorphic DNA (RAPD) analysis with selected primers confirmed that these plants are indeed interspecific hybrids. Some plants are female-fertile and production of backcross progenies with L. sativa is in progress. Since many desirable traits such as resistances to viruses, bacteria and fungi (Bremia lactucae) have been characterized in wild Lactuca species, the use of somatic hybridization in breeding programmes now appears a practical possibility.