Genome-Wide Analysis of Soybean HD-Zip Gene Family and Expression Profiling under Salinity and Drought Treatments

PubMed Central

Chen, Xue; Chen, Zhu; Zhao, Hualin; Zhao, Yang; Cheng, Beijiu; Xiang, Yan

2014-01-01

Background Homeodomain-leucine zipper (HD-Zip) proteins, a group of homeobox transcription factors, participate in various aspects of normal plant growth and developmental processes as well as environmental responses. To date, no overall analysis or expression profiling of the HD-Zip gene family in soybean (Glycine max) has been reported. Methods and Findings An investigation of the soybean genome revealed 88 putative HD-Zip genes. These genes were classified into four subfamilies, I to IV, based on phylogenetic analysis. In each subfamily, the constituent parts of gene structure and motif were relatively conserved. A total of 87 out of 88 genes were distributed unequally on 20 chromosomes with 36 segmental duplication events, indicating that segmental duplication is important for the expansion of the HD-Zip family. Analysis of the Ka/Ks ratios showed that the duplicated genes of the HD-Zip family basically underwent purifying selection with restrictive functional divergence after the duplication events. Analysis of expression profiles showed that 80 genes differentially expressed across 14 tissues, and 59 HD-Zip genes are differentially expressed under salinity and drought stress, with 20 paralogous pairs showing nearly identical expression patterns and three paralogous pairs diversifying significantly under drought stress. Quantitative real-time RT-PCR (qRT-PCR) analysis of six paralogous pairs of 12 selected soybean HD-Zip genes under both drought and salinity stress confirmed their stress-inducible expression patterns. Conclusions This study presents a thorough overview of the soybean HD-Zip gene family and provides a new perspective on the evolution of this gene family. The results indicate that HD-Zip family genes may be involved in many plant responses to stress conditions. Additionally, this study provides a solid foundation for uncovering the biological roles of HD-Zip genes in soybean growth and development. PMID:24498296

Systematic Analysis of Sequences and Expression Patterns of Drought-Responsive Members of the HD-Zip Gene Family in Maize

PubMed Central

Zhao, Yang; Zhou, Yuqiong; Jiang, Haiyang; Li, Xiaoyu; Gan, Defang; Peng, Xiaojian; Zhu, Suwen; Cheng, Beijiu

2011-01-01

Background Members of the homeodomain-leucine zipper (HD-Zip) gene family encode transcription factors that are unique to plants and have diverse functions in plant growth and development such as various stress responses, organ formation and vascular development. Although systematic characterization of this family has been carried out in Arabidopsis and rice, little is known about HD-Zip genes in maize (Zea mays L.). Methods and Findings In this study, we described the identification and structural characterization of HD-Zip genes in the maize genome. A complete set of 55 HD-Zip genes (Zmhdz1-55) were identified in the maize genome using Blast search tools and categorized into four classes (HD-Zip I-IV) based on phylogeny. Chromosomal location of these genes revealed that they are distributed unevenly across all 10 chromosomes. Segmental duplication contributed largely to the expansion of the maize HD-ZIP gene family, while tandem duplication was only responsible for the amplification of the HD-Zip II genes. Furthermore, most of the maize HD-Zip I genes were found to contain an overabundance of stress-related cis-elements in their promoter sequences. The expression levels of the 17 HD-Zip I genes under drought stress were also investigated by quantitative real-time PCR (qRT-PCR). All of the 17 maize HD-ZIP I genes were found to be regulated by drought stress, and the duplicated genes within a sister pair exhibited the similar expression patterns, suggesting their conserved functions during the process of evolution. Conclusions Our results reveal a comprehensive overview of the maize HD-Zip gene family and provide the first step towards the selection of Zmhdz genes for cloning and functional research to uncover their roles in maize growth and development. PMID:22164299

Systematic analysis of sequences and expression patterns of drought-responsive members of the HD-Zip gene family in maize.

PubMed

Zhao, Yang; Zhou, Yuqiong; Jiang, Haiyang; Li, Xiaoyu; Gan, Defang; Peng, Xiaojian; Zhu, Suwen; Cheng, Beijiu

2011-01-01

Members of the homeodomain-leucine zipper (HD-Zip) gene family encode transcription factors that are unique to plants and have diverse functions in plant growth and development such as various stress responses, organ formation and vascular development. Although systematic characterization of this family has been carried out in Arabidopsis and rice, little is known about HD-Zip genes in maize (Zea mays L.). In this study, we described the identification and structural characterization of HD-Zip genes in the maize genome. A complete set of 55 HD-Zip genes (Zmhdz1-55) were identified in the maize genome using Blast search tools and categorized into four classes (HD-Zip I-IV) based on phylogeny. Chromosomal location of these genes revealed that they are distributed unevenly across all 10 chromosomes. Segmental duplication contributed largely to the expansion of the maize HD-ZIP gene family, while tandem duplication was only responsible for the amplification of the HD-Zip II genes. Furthermore, most of the maize HD-Zip I genes were found to contain an overabundance of stress-related cis-elements in their promoter sequences. The expression levels of the 17 HD-Zip I genes under drought stress were also investigated by quantitative real-time PCR (qRT-PCR). All of the 17 maize HD-ZIP I genes were found to be regulated by drought stress, and the duplicated genes within a sister pair exhibited the similar expression patterns, suggesting their conserved functions during the process of evolution. Our results reveal a comprehensive overview of the maize HD-Zip gene family and provide the first step towards the selection of Zmhdz genes for cloning and functional research to uncover their roles in maize growth and development.

PpHB22, a member of HD-Zip proteins, activates PpDAM1 to regulate bud dormancy transition in 'Suli' pear (Pyrus pyrifolia White Pear Group).

PubMed

Yang, Qinsong; Niu, Qingfeng; Li, Jianzhao; Zheng, Xiaoyan; Ma, Yunjing; Bai, Songling; Teng, Yuanwen

2018-06-01

Homeodomain-leucine zipper (HD-Zip) proteins, which form one of the largest and most diverse families, regulate many biological processes in plants, including differentiation, flowering, vascular development, and stress signaling. Abscisic acid (ABA) has been proved to be one of the key regulators of bud dormancy and to influence several HD-Zip genes expression. However, the role of HD-Zip genes in regulating bud dormancy remains unclear. We identified 47 pear (P. pyrifolia White Pear Group) HD-Zip genes, which were classified into four subfamilies (HD-Zip I-IV). We further revealed that gene expression levels of some HD-Zip members were closely related to ABA concentrations in flower buds during dormancy transition. Exogenous ABA treatment confirmed that PpHB22 and several other HD-Zip genes responded to ABA. Yeast one-hybrid and dual luciferase assay results combining subcellular localization showed that PpHB22 was present in nucleus and directly induced PpDAM1 (dormancy associated MADS-box 1) expression. Thus, PpHB22 is a negative regulator of plant growth associated with the ABA response pathway and functions upstream of PpDAM1. These findings enrich our understanding of the function of HD-Zip genes related to the bud dormancy transition. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Developmental and seasonal expression of PtaHB1, a Populus gene encoding a class III HD-Zip protein, is closely associated with secondary growth and inversely correlated with the level of microRNA (miR166).

PubMed

Ko, Jae-Heung; Prassinos, Constantinos; Han, Kyung-Hwan

2006-01-01

In contrast to our knowledge of the shoot apical meristem, our understanding of cambium meristem differentiation and maintenance is limited. Class III homeodomain leucine-zipper (HD-Zip) proteins have been shown to play a regulatory role in vascular differentiation. The hybrid aspen (Populus tremulaxPopulus alba) class III HD-Zip transcription factor (PtaHB1) and microRNA 166 (Pta-miR166) family were cloned from hybrid aspen using a combination of in silico and polymerase chain reaction methods. Expression analyses of PtaHB1 and Pta-miR166 were performed by Northern blot analysis. The expression of PtaHB1 was closely associated with wood formation and regulated both developmentally and seasonally, with the highest expression during the active growing season. Also, its expression was inversely correlated with the level of Pta-miR166. Pta-miR166-directed cleavage of PtaHB1 in vivo was confirmed using modified 5'-rapid amplification of cDNA ends (RACE). The expression of Pta-miR166 was much higher in the winter than in the growing seasons, suggesting seasonal and developmental regulation of microRNA in this perennial plant species.

Stage-specific regulation of four HD-ZIP III transcription factors during polar pattern formation in Larix leptolepis somatic embryos.

PubMed

Li, Shui-gen; Li, Wan-feng; Han, Su-ying; Yang, Wen-hua; Qi, Li-wang

2013-06-15

Polar auxin transport provides a developmental signal for cell fate specification during somatic embryogenesis. Some members of the HD-ZIP III transcription factors participate in regulation of auxin transport, but little is known about this regulation in somatic embryogenesis. Here, four HD-ZIP III homologues from Larix leptolepis were identified and designated LaHDZ31, 32, 33 and 34. The occurrence of a miR165/166 target sequence in all four cDNA sequences indicated that they might be targets of miR165/166. Identification of the cleavage products of LaHDZ31 and LaHDZ32 in vivo confirmed that they were regulated by miRNA. Their mRNA accumulation patterns during somatic embryogenesis and the effects of 1-N-naphthylphthalamic acid (NPA) on their transcript levels and somatic embryo maturation were investigated. The results showed that the four genes had higher transcript levels at mature stages than at the proliferation stage, and that NPA treatment down-regulated the mRNA abundance of LaHDZ31, 32 and 33 at cotyledonary embryo stages, but had no effect on the mRNA abundance of LaHDZ34. We concluded that these four members of Larix HD-ZIP III family might participate in polar auxin transport and the development of somatic embryos, providing new insights into the regulatory mechanisms of somatic embryogenesis. Copyright © 2013 Elsevier B.V. All rights reserved.

Abscisic acid signaling is controlled by a BRANCHED1/HD-ZIP I cascade in Arabidopsis axillary buds.

PubMed

González-Grandío, Eduardo; Pajoro, Alice; Franco-Zorrilla, José M; Tarancón, Carlos; Immink, Richard G H; Cubas, Pilar

2017-01-10

Shoot-branching patterns determine key aspects of plant life and are important targets for crop breeding. However, we are still largely ignorant of the genetic networks controlling locally the most important decision during branch development: whether the axillary bud, or branch primordium, grows out to give a lateral shoot or remains dormant. Here we show that, inside the buds, the TEOSINTE BRANCHED1, CYCLOIDEA, PCF (TCP) transcription factor BRANCHED1 (BRC1) binds to and positively regulates the transcription of three related Homeodomain leucine zipper protein (HD-ZIP)-encoding genes: HOMEOBOX PROTEIN 21 (HB21), HOMEOBOX PROTEIN 40 (HB40), and HOMEOBOX PROTEIN 53 (HB53). These three genes, together with BRC1, enhance 9-CIS-EPOXICAROTENOID DIOXIGENASE 3 (NCED3) expression, lead to abscisic acid accumulation, and trigger hormone response, thus causing suppression of bud development. This TCP/HD-ZIP genetic module seems to be conserved in dicot and monocotyledonous species to prevent branching under light-limiting conditions.

A conserved proline residue in the leucine zipper region of AtbZIP34 and AtbZIP61 in Arabidopsis thaliana interferes with the formation of homodimer.

PubMed

Shen, Huaishun; Cao, Kaiming; Wang, Xiping

2007-10-19

Two putative Arabidopsis E group bZIP transcript factors, AtbZIP34 and AtbZIP61, are nuclear-localized and their transcriptional activation domain is in their N-terminal region. By searching GenBank, we found other eight plant homologues of AtbZIP34 and AtbZIP61. All of them have a proline residue in the third heptad of zipper region. Yeast two-hybrid assay and EMSA showed that AtbZIP34 and AtbZIP61 could not form homodimer while their mutant forms, AtbZIP34m and AtbZIP61m, which the proline residue was replaced by an alanine residue in the zipper region, could form homodimer and bind G-box element. These results suggest that the conserved proline residue interferes with the homodimer formation. However, both AtbZIP34 and AtbZIP61 could form heterodimers with members of I group and S group transcription factors in which some members involved in vascular development. So we speculate that AtbZIP34 and AtbZIP61 may participate in plant development via interacting with other group bZIP transcription factors.

Two Cassava Basic Leucine Zipper (bZIP) Transcription Factors (MebZIP3 and MebZIP5) Confer Disease Resistance against Cassava Bacterial Blight.

PubMed

Li, Xiaolin; Fan, Shuhong; Hu, Wei; Liu, Guoyin; Wei, Yunxie; He, Chaozu; Shi, Haitao

2017-01-01

Basic domain-leucine zipper (bZIP) transcription factor, one type of conserved gene family, plays an important role in plant development and stress responses. Although 77 MebZIPs have been genome-wide identified in cassava, their in vivo roles remain unknown. In this study, we analyzed the expression pattern and the function of two MebZIPs ( MebZIP3 and MebZIP5 ) in response to pathogen infection. Gene expression analysis indicated that MebZIP3 and MebZIP5 were commonly regulated by flg22, Xanthomonas axonopodis pv. manihotis ( Xam ), salicylic acid (SA), and hydrogen peroxide (H 2 O 2 ). Subcellular localization analysis showed that MebZIP3 and MebZIP5 are specifically located in cell nucleus. Through overexpression in tobacco, we found that MebZIP3 and MebZIP5 conferred improved disease resistance against cassava bacterial blight, with more callose depositions. On the contrary, MebZIP3- and MebZIP5 -silenced plants by virus-induced gene silencing (VIGS) showed disease sensitive phenotype, lower transcript levels of defense-related genes and less callose depositions. Taken together, this study highlights the positive role of MebZIP3 and MebZIP5 in disease resistance against cassava bacterial blight for further utilization in genetic improvement of cassava disease resistance.

Genome-Wide Investigation and Expression Profiling of HD-Zip Transcription Factors in Foxtail Millet (Setaria italica L.).

PubMed

Chai, Wenbo; Si, Weina; Ji, Wei; Qin, Qianqian; Zhao, Manli; Jiang, Haiyang

2018-01-01

HD-Zip proteins represent the major transcription factors in higher plants, playing essential roles in plant development and stress responses. Foxtail millet is a crop to investigate the systems biology of millet and biofuel grasses and the HD-Zip gene family has not been studied in foxtail millet. For further investigation of the expression profile of the HD-Zip gene family in foxtail millet, a comprehensive genome-wide expression analysis was conducted in this study. We found 47 protein-encoding genes in foxtail millet using BLAST search tools; the putative proteins were classified into four subfamilies, namely, subfamilies I, II, III, and IV. Gene structure and motif analysis indicate that the genes in one subfamily were conserved. Promotor analysis showed that HD-Zip gene was involved in abiotic stress. Duplication analysis revealed that 8 (~17%) hdz genes were tandemly duplicated and 28 (58%) were segmentally duplicated; purifying duplication plays important roles in gene expansion. Microsynteny analysis revealed the maximum relationship in foxtail millet-sorghum and foxtail millet-rice. Expression profiling upon the abiotic stresses of drought and high salinity and the biotic stress of ABA revealed that some genes regulated responses to drought and salinity stresses via an ABA-dependent process, especially sihdz29 and sihdz45. Our study provides new insight into evolutionary and functional analyses of HD-Zip genes involved in environmental stress responses in foxtail millet.

In Planta Single-Molecule Pull-Down Reveals Tetrameric Stoichiometry of HD-ZIPIII:LITTLE ZIPPER Complexes.

PubMed

Husbands, Aman Y; Aggarwal, Vasudha; Ha, Taekjip; Timmermans, Marja C P

2016-08-01

Deciphering complex biological processes markedly benefits from approaches that directly assess the underlying biomolecular interactions. Most commonly used approaches to monitor protein-protein interactions typically provide nonquantitative readouts that lack statistical power and do not yield information on the heterogeneity or stoichiometry of protein complexes. Single-molecule pull-down (SiMPull) uses single-molecule fluorescence detection to mitigate these disadvantages and can quantitatively interrogate interactions between proteins and other compounds, such as nucleic acids, small molecule ligands, and lipids. Here, we establish SiMPull in plants using the HOMEODOMAIN LEUCINE ZIPPER III (HD-ZIPIII) and LITTLE ZIPPER (ZPR) interaction as proof-of-principle. Colocalization analysis of fluorophore-tagged HD-ZIPIII and ZPR proteins provides strong statistical evidence of complex formation. In addition, we use SiMPull to directly quantify YFP and mCherry maturation probabilities, showing these differ substantially from values obtained in mammalian systems. Leveraging these probabilities, in conjunction with fluorophore photobleaching assays on over 2000 individual complexes, we determined HD-ZIPIII:ZPR stoichiometry. Intriguingly, these complexes appear as heterotetramers, comprising two HD-ZIPIII and two ZPR molecules, rather than heterodimers as described in the current model. This surprising result raises new questions about the regulation of these key developmental factors and is illustrative of the unique contribution SiMPull is poised to make to in planta protein interaction studies. © 2016 American Society of Plant Biologists. All rights reserved.

Genome-Wide Identification, Evolutionary Expansion, and Expression Profile of Homeodomain-Leucine Zipper Gene Family in Poplar (Populus trichocarpa)

PubMed Central

Hu, Ruibo; Chi, Xiaoyuan; Chai, Guohua; Kong, Yingzhen; He, Guo; Wang, Xiaoyu; Shi, Dachuan; Zhang, Dongyuan; Zhou, Gongke

2012-01-01

Background Homeodomain-leucine zipper (HD-ZIP) proteins are plant-specific transcriptional factors known to play crucial roles in plant development. Although sequence phylogeny analysis of Populus HD-ZIPs was carried out in a previous study, no systematic analysis incorporating genome organization, gene structure, and expression compendium has been conducted in model tree species Populus thus far. Principal Findings In this study, a comprehensive analysis of Populus HD-ZIP gene family was performed. Sixty-three full-length HD-ZIP genes were found in Populus genome. These Populus HD-ZIP genes were phylogenetically clustered into four distinct subfamilies (HD-ZIP I–IV) and predominately distributed across 17 linkage groups (LG). Fifty genes from 25 Populus paralogous pairs were located in the duplicated blocks of Populus genome and then preferentially retained during the sequential evolutionary courses. Genomic organization analyses indicated that purifying selection has played a pivotal role in the retention and maintenance of Populus HD-ZIP gene family. Microarray analysis has shown that 21 Populus paralogous pairs have been differentially expressed across different tissues and under various stresses, with five paralogous pairs showing nearly identical expression patterns, 13 paralogous pairs being partially redundant and three paralogous pairs diversifying significantly. Quantitative real-time RT-PCR (qRT-PCR) analysis performed on 16 selected Populus HD-ZIP genes in different tissues and under both drought and salinity stresses confirms their tissue-specific and stress-inducible expression patterns. Conclusions Genomic organizations indicated that segmental duplications contributed significantly to the expansion of Populus HD-ZIP gene family. Exon/intron organization and conserved motif composition of Populus HD-ZIPs are highly conservative in the same subfamily, suggesting the members in the same subfamilies may also have conservative functionalities

Flavonoids modify root growth and modulate expression of SHORT-ROOT and HD-ZIP III.

PubMed

Franco, Danilo Miralha; Silva, Eder Marques; Saldanha, Luiz Leonardo; Adachi, Sérgio Akira; Schley, Thayssa Rabelo; Rodrigues, Tatiane Maria; Dokkedal, Anne Ligia; Nogueira, Fabio Tebaldi Silveira; Rolim de Almeida, Luiz Fernando

2015-09-01

Flavonoids are a class of distinct compounds produced by plant secondary metabolism that inhibit or promote plant development and have a relationship with auxin transport. We showed that, in terms of root development, Copaifera langsdorffii leaf extracts has an inhibitory effect on most flavonoid components compared with the application of exogenous flavonoids (glycosides and aglycones). These compounds alter the pattern of expression of the SHORT-ROOT and HD-ZIP III transcription factor gene family and cause morpho-physiological alterations in sorghum roots. In addition, to examine the flavonoid auxin interaction in stress, we correlated the responses with the effects of exogenous application of auxin and an auxin transport inhibitor. The results show that exogenous flavonoids inhibit primary root growth and increase the development of lateral roots. Exogenous flavonoids also change the pattern of expression of specific genes associated with root tissue differentiation. These findings indicate that flavonoid glycosides can influence the polar transport of auxin, leading to stress responses that depend on auxin. Copyright © 2015 Elsevier GmbH. All rights reserved.

Genome-wide analysis of the basic leucine zipper (bZIP) transcription factor gene family in six legume genomes.

PubMed

Wang, Zhihui; Cheng, Ke; Wan, Liyun; Yan, Liying; Jiang, Huifang; Liu, Shengyi; Lei, Yong; Liao, Boshou

2015-12-10

Plant bZIP proteins characteristically harbor a highly conserved bZIP domain with two structural features: a DNA-binding basic region and a leucine (Leu) zipper dimerization region. They have been shown to be diverse transcriptional regulators, playing crucial roles in plant development, physiological processes, and biotic/abiotic stress responses. Despite the availability of six completely sequenced legume genomes, a comprehensive investigation of bZIP family members in legumes has yet to be presented. In this study, we identified 428 bZIP genes encoding 585 distinct proteins in six legumes, Glycine max, Medicago truncatula, Phaseolus vulgaris, Cicer arietinum, Cajanus cajan, and Lotus japonicus. The legume bZIP genes were categorized into 11 groups according to their phylogenetic relationships with genes from Arabidopsis. Four kinds of intron patterns (a-d) within the basic and hinge regions were defined and additional conserved motifs were identified, both presenting high group specificity and supporting the group classification. We predicted the DNA-binding patterns and the dimerization properties, based on the characteristic features in the basic and hinge regions and the Leu zipper, respectively, which indicated that some highly conserved amino acid residues existed across each major group. The chromosome distribution and analysis for WGD-derived duplicated blocks revealed that the legume bZIP genes have expanded mainly by segmental duplication rather than tandem duplication. Expression data further revealed that the legume bZIP genes were expressed constitutively or in an organ-specific, development-dependent manner playing roles in multiple seed developmental stages and tissues. We also detected several key legume bZIP genes involved in drought- and salt-responses by comparing fold changes of expression values in drought-stressed or salt-stressed roots and leaves. In summary, this genome-wide identification, characterization and expression analysis of

Class III HD-Zip activity coordinates leaf development in Physcomitrella patens.

PubMed

Yip, Hoichong Karen; Floyd, Sandra K; Sakakibara, Keiko; Bowman, John L

2016-11-01

Land plant bodies develop from meristems, groups of pluripotent stem cells, which may persist throughout the life of a plant or, alternatively, have a transitory existence. Early diverging land plants exhibit indeterminate (persistent) growth in their haploid gametophytic generation, whereas later diverging lineages exhibit indeterminate growth in their diploid sporophytic generation, raising the question of whether genetic machinery directing meristematic functions was co-opted between generations. Class III HD-Zip (C3HDZ) genes are required for the establishment and maintenance of shoot apical meristems in flowering plants. We demonstrate that in the moss Physcomitrella patens, C3HDZ genes are expressed in transitory meristems in both the gametophytic and sporophytic generations, but not in the persistent shoot meristem of the gametyphyte. Loss-of-function of P. patens C3HDZ was engineered using ectopic expression of miR166, an endogenous regulator of C3HDZ gene activity. Loss of C3HDZ gene function impaired the function of gametophytic transitory meristematic activity but did not compromise the functioning of the persistent shoot apical meristem during the gametophyte generation. These results argue against a wholesale co-option of meristematic gene regulatory networks from the gametophyte to the sporophyte during land plant evolution, instead suggesting that persistent meristems with a single apical cell in P. patens and persistent complex meristems in flowering plants are regulated by different genetic programs. Copyright © 2016 Elsevier Inc. All rights reserved.

Basic leucine zipper transcription factor SlbZIP1 mediates salt and drought stress tolerance in tomato.

PubMed

Zhu, Mingku; Meng, Xiaoqing; Cai, Jing; Li, Ge; Dong, Tingting; Li, Zongyun

2018-05-08

Basic region/leucine zipper (bZIP) transcription factors perform as crucial regulators in ABA-mediated stress response in plants. Nevertheless, the functions for most bZIP family members in tomato remain to be deciphered. Here we examined the functional characterization of SlbZIP1 under salt and drought stresses in tomato. Silencing of SlbZIP1 in tomato resulted in reduced expression of multiple ABA biosynthesis- and signal transduction-related genes in transgenic plants. In stress assays, SlbZIP1-RNAi transgenic plants exhibited reduced tolerance to salt and drought stresses compared with WT plants, as are evaluated by multiple physiological parameters associated with stress responses, such as decreased ABA, chlorophyll contents and CAT activity, and increased MDA content. In addition, RNA-seq analysis of transgenic plants revealed that the transcription levels of multiple genes encoding defense proteins related to responses to abiotic stress (e.g. endochitinase, peroxidases, and lipid transfer proteins) and biotic stress (e.g. pathogenesis-related proteins) were downregulated in SlbZIP1-RNAi plants, suggesting that SlbZIP1 plays a role in regulating the genes related to biotic and abiotic stress response. Collectively, the data suggest that SlbZIP1 exerts an essential role in salt and drought stress tolerance through modulating an ABA-mediated pathway, and SlbZIP1 may hold potential applications in the engineering of salt- and drought-tolerant tomato cultivars.

Influence of the valine zipper region on the structure and aggregation of the basic leucine zipper (bZIP) domain of activating transcription factor 5 (ATF5).

PubMed

Ciaccio, Natalie A; Reynolds, T Steele; Middaugh, C Russell; Laurence, Jennifer S

2012-11-05

Protein aggregation is a major problem for biopharmaceuticals. While the control of aggregation is critically important for the future of protein pharmaceuticals, mechanisms of aggregate assembly, particularly the role that structure plays, are still poorly understood. Increasing evidence indicates that partially folded intermediates critically influence the aggregation pathway. We have previously reported the use of the basic leucine zipper (bZIP) domain of activating transcription factor 5 (ATF5) as a partially folded model system to investigate protein aggregation. This domain contains three regions with differing structural propensity: a N-terminal polybasic region, a central helical leucine zipper region, and a C-terminal extended valine zipper region. Additionally, a centrally positioned cysteine residue readily forms an intermolecular disulfide bond that reduces aggregation. Computational analysis of ATF5 predicts that the valine zipper region facilitates self-association. Here we test this hypothesis using a truncated mutant lacking the C-terminal valine zipper region. We compare the structure and aggregation of this mutant to the wild-type (WT) form under both reducing and nonreducing conditions. Our data indicate that removal of this region results in a loss of α-helical structure in the leucine zipper and a change in the mechanism of self-association. The mutant form displays increased association at low temperature but improved resistance to thermally induced aggregation.

Structure of homeodomain-leucine zipper/DNA complexes studied using hydroxyl radical cleavage of DNA and methylation interference.

PubMed

Tron, Adriana E; Comelli, Raúl N; Gonzalez, Daniel H

2005-12-27

Homeodomain-leucine zipper (HD-Zip) proteins, unlike most homeodomain proteins, bind a pseudopalindromic DNA sequence as dimers. We have investigated the structure of the DNA complexes formed by two HD-Zip proteins with different nucleotide preferences at the central position of the binding site using footprinting and interference methods. The results indicate that the respective complexes are not symmetric, with the strand bearing a central purine (top strand) showing higher protection around the central region and the bottom strand protected toward the 3' end. Binding to a sequence with a nonpreferred central base pair produces a decrease in protection in either the top or the bottom strand, depending upon the protein. Modeling studies derived from the complex formed by the monomeric Antennapedia homeodomain with DNA indicate that in the HD-Zip/DNA complex the recognition helix of one of the monomers is displaced within the major groove respective to the other one. This monomer seems to lose contacts with a part of the recognition sequence upon binding to the nonpreferred site. The results show that the structure of the complex formed by HD-Zip proteins with DNA is dependent upon both protein intrinsic characteristics and the nucleotides present at the central position of the recognition sequence.

Evolution and expression analysis reveal the potential role of the HD-Zip gene family in regulation of embryo abortion in grapes (Vitis vinifera L.).

PubMed

Li, Zhiqian; Zhang, Chen; Guo, Yurui; Niu, Weili; Wang, Yuejin; Xu, Yan

2017-09-21

The HD-Zip family has a diversity of functions during plant development. In this study, we identify 33 HD-Zip transcription factors in grape and detect their expressions in ovules and somatic embryos, as well as in various vegetative organs. A genome-wide survey for HD-Zip transcription factors in Vitis was conducted based on the 12 X grape genome (V. vinifera L.). A total of 33 members were identified and classified into four subfamilies (I-IV) based on phylogeny analysis with Arabidopsis, rice and maize. VvHDZs in the same subfamily have similar protein motifs and intron/exon structures. An evaluation of duplication events suggests several HD-Zip genes arose before the divergence of the grape and Arabidopsis lineages. The 33 members of HD-Zip were differentially expressed in ovules of the stenospermic grape, Thompson Seedless and of the seeded grape, Pinot noir. Most have higher expressions during ovule abortion in Thompson Seedless. In addition, transcripts of the HD-Zip family were also detected in somatic embryogenesis of Thompson Seedless and in different vegetative organs of Thompson Seedless at varying levels. Additionally, VvHDZ28 is located in the nucleus and had transcriptional activity consistent with the typical features of the HD-Zip family. Our results provide a foundation for future grape HD-Zip gene function research. The identification and expression profiles of the HD-Zip transcription factors in grape, reveal their diverse roles during ovule abortion and organ development. Our results lay a foundation for functional analysis of grape HDZ genes.

Abscisic-acid-dependent basic leucine zipper (bZIP) transcription factors in plant abiotic stress.

PubMed

Banerjee, Aditya; Roychoudhury, Aryadeep

2017-01-01

One of the major causes of significant crop loss throughout the world is the myriad of environmental stresses including drought, salinity, cold, heavy metal toxicity, and ultraviolet-B (UV-B) rays. Plants as sessile organisms have evolved various effective mechanism which enable them to withstand this plethora of stresses. Most of such regulatory mechanisms usually follow the abscisic-acid (ABA)-dependent pathway. In this review, we have primarily focussed on the basic leucine zipper (bZIP) transcription factors (TFs) activated by the ABA-mediated signalosome. Upon perception of ABA by specialized receptors, the signal is transduced via various groups of Ser/Thr kinases, which phosphorylate the bZIP TFs. Following such post-translational modification of TFs, they are activated so that they bind to specific cis-acting sequences called abscisic-acid-responsive elements (ABREs) or GC-rich coupling elements (CE), thereby influencing the expression of their target downstream genes. Several in silico techniques have been adopted so far to predict the structural features, recognize the regulatory modification sites, undergo phylogenetic analyses, and facilitate genome-wide survey of TF under multiple stresses. Current investigations on the epigenetic regulation that controls greater accessibility of the inducible regions of DNA of the target gene to the bZIP TFs exclusively under stress situations, along with the evolved stress memory responses via genomic imprinting mechanism, have been highlighted. The potentiality of overexpression of bZIP TFs, either in a homologous or in a heterologous background, in generating transgenic plants tolerant to various abiotic stressors have also been addressed by various groups. The present review will provide a coherent documentation on the functional characterization and regulation of bZIP TFs under multiple environmental stresses, with the major goal of generating multiple-stress-tolerant plant cultivars in near future.

A basic leucine zipper transcription factor, AabZIP1, connects abscisic acid signaling with artemisinin biosynthesis in Artemisia annua.

PubMed

Zhang, Fangyuan; Fu, Xueqing; Lv, Zongyou; Lu, Xu; Shen, Qian; Zhang, Ling; Zhu, Mengmeng; Wang, Guofeng; Sun, Xiaofen; Liao, Zhihua; Tang, Kexuan

2015-01-01

Artemisinin is a sesquiterpenoid especially synthesized in the Chinese herbal plant, Artemisia annua, which is widely used in the treatment of malaria. Artemisinin accumulation can be enhanced by exogenous abscisic acid (ABA) treatment. However, it is not known how ABA signaling regulates artemisinin biosynthesis. A global expression profile and phylogenetic analysis as well as the dual-LUC screening revealed that a basic leucine zipper family transcription factor from A. annua (namely AabZIP1) was involved in ABA signaling to regulate artemisinin biosynthesis. AabZIP1 had a higher expression level in the inflorescences than in other tissues; ABA treatment, drought, and salt stress strongly induced the expression of AabZIP1. Yeast one-hybrid assay and electrophoretic mobility shift assay (EMSA) showed that AabZIP1 bound to the ABA-responsive elements (ABRE) in the promoter regions of the amorpha-4,11-diene synthase (ADS) gene and CYP71AV1, which are two key structural genes of the artemisinin biosynthetic pathway. A mutagenesis assay showed that the C1 domain in the N-terminus of AabZIP1 was important for its transactivation activity. Furthermore, the activation of ADS and CYP71AV1 promoters by AabZIP1 was enhanced by ABA treatment in transient dual-LUC analysis. The AabZIP1 variant with C1 domain deletion lost the ability to activate ADS and CYP71AV1 promoters regardless of ABA treatment. Notably, overexpression of AabZIP1 in A. annua resulted in significantly increased accumulation of artemisinin. Our results indicate that ABA promotes artemisinin biosynthesis, likely through 1 activation of ADS and CYP71AV1 expression by AabZIP in A. annua. Meanwhile, our findings reveal the potential value of AabZIP1 in genetic engineering of artemisinin production. Copyright © 2015 The Author. Published by Elsevier Inc. All rights reserved.

Engineering of a novel zipFv using leucine zipper motif against rabies virus glycoprotein G with improved protection potency in vivo.

PubMed

Xi, Hualong; Zhang, Kaixin; Yin, Yanchun; Gu, Tiejun; Sun, Qing; Li, Zhuang; Cheng, Yue; Jiang, Chunlai; Kong, Wei; Wu, Yongge

2017-06-01

Rabies is an acute zoonotic infectious disease with a high fatality rate but is preventable with vaccination and rabies immunoglobulin (RIG). The single-chain Fv fragment (scFv), a small engineered antigen-binding protein derived from antibody variable heavy (V H ) and light (V L ) chains connected by a peptide linker, can potentially be used to replace RIG. Here, we produced two peptides V H -JUN-HIS and V L -FOS-HA separately in Escherichia coli and assembled them to form zipFv successfully in vitro. The new zipFv utilizes FOS and JUN leucine zippers to form an antibody structure similar to the IgG counterpart with two free N-terminal ends of V H and V L . The zipFv protein showed notable improvement in binding ability and affinity over its corresponding scFv. The zipFv also demonstrated greater stability in serum and the same protective rate as RIG against challenge with a standard rabies virus (CVS-24) in mice. Our results indicated zipFv as a novel and efficient antibody form with enhanced neutralizing potency. Copyright © 2017. Published by Elsevier B.V.

Evolutionary and Expression Analyses of the Apple Basic Leucine Zipper Transcription Factor Family.

PubMed

Zhao, Jiao; Guo, Rongrong; Guo, Chunlei; Hou, Hongmin; Wang, Xiping; Gao, Hua

2016-01-01

Transcription factors (TFs) play essential roles in the regulatory networks controlling many developmental processes in plants. Members of the basic leucine (Leu) zipper (bZIP) TF family, which is unique to eukaryotes, are involved in regulating diverse processes, including flower and vascular development, seed maturation, stress signaling, and defense responses to pathogens. The bZIP proteins have a characteristic bZIP domain composed of a DNA-binding basic region and a Leu zipper dimerization region. In this study, we identified 112 apple (Malus domestica Borkh) bZIP TF-encoding genes, termed MdbZIP genes. Synteny analysis indicated that segmental and tandem duplication events, as well as whole genome duplication, have contributed to the expansion of the apple bZIP family. The family could be divided into 11 groups based on structural features of the encoded proteins, as well as on the phylogenetic relationship of the apple bZIP proteins to those of the model plant Arabidopsis thaliana (AtbZIP genes). Synteny analysis revealed that several paired MdbZIP genes and AtbZIP gene homologs were located in syntenic genomic regions. Furthermore, expression analyses of group A MdbZIP genes showed distinct expression levels in 10 different organs. Moreover, changes in these expression profiles in response to abiotic stress conditions and various hormone treatments identified MdbZIP genes that were responsive to high salinity and drought, as well as to different phytohormones.

Chickpea WRKY70 Regulates the Expression of a Homeodomain-Leucine Zipper (HD-Zip) I Transcription Factor CaHDZ12, which Confers Abiotic Stress Tolerance in Transgenic Tobacco and Chickpea.

PubMed

Sen, Senjuti; Chakraborty, Joydeep; Ghosh, Prithwi; Basu, Debabrata; Das, Sampa

2017-11-01

Drought and salinity are the two major environmental constraints that severely affect global agricultural productivity. Plant-specific HD-Zip transcription factors are involved in plant growth, development and stress responses. In the present study, we explored the functional characteristics and regulation of a novel HD-Zip (I) gene from chickpea, CaHDZ12, in response to water-deficit and salt-stress conditions. Transgenic tobacco lines over-expressing CaHDZ12 exhibited improved tolerance to osmotic stresses and increased sensitivity to abscisic acid (ABA). Physiological compatibility of transgenic lines was found to be more robust compared to the wild-type plants under drought and salinity stress. Additionally, expression of several stress-responsive genes was significantly induced in CaHDZ12 transgenic plants. On the other hand, silencing of CaHDZ12 in chickpea resulted in increased sensitivity to salt and drought stresses. Analysis of different promoter deletion mutants identified CaWRKY70 transcription factor as a transcriptional regulator of CaHDZ12 expression. In vivo and in vitro interaction studies detected an association between CaWRKY70 and CaHDZ12 promoter during stress responses. Epigenetic modifications underlying histone acetylation at the CaHDZ12 promoter region play a significant role in stress-induced activation of this gene. Collectively, our study describes a crucial and unique mechanistic link between two distinct transcription factors in regulating plant adaptive stress response. © The Author 2017. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Establishing a Framework for the Ad/Abaxial Regulatory Network of Arabidopsis: Ascertaining Targets of Class III HOMEODOMAIN LEUCINE ZIPPER and KANADI Regulation[W

PubMed Central

Reinhart, Brenda J.; Liu, Tie; Newell, Nicole R.; Magnani, Enrico; Huang, Tengbo; Kerstetter, Randall; Michaels, Scott; Barton, M. Kathryn

2013-01-01

The broadly conserved Class III HOMEODOMAIN LEUCINE ZIPPER (HD-ZIPIII) and KANADI transcription factors have opposing and transformational effects on polarity and growth in all tissues and stages of the plant's life. To obtain a comprehensive understanding of how these factors work, we have identified transcripts that change in response to induced HD-ZIPIII or KANADI function. Additional criteria used to identify high-confidence targets among this set were presence of an adjacent HD-ZIPIII binding site, expression enriched within a subdomain of the shoot apical meristem, mutant phenotype showing defect in polar leaf and/or meristem development, physical interaction between target gene product and HD-ZIPIII protein, opposite regulation by HD-ZIPIII and KANADI, and evolutionary conservation of the regulator–target relationship. We find that HD-ZIPIII and KANADI regulate tissue-specific transcription factors involved in subsidiary developmental decisions, nearly all major hormone pathways, and new actors (such as INDETERMINATE DOMAIN4) in the ad/abaxial regulatory network. Multiple feedback loops regulating HD-ZIPIII and KANADI are identified, as are mechanisms through which HD-ZIPIII and KANADI oppose each other. This work lays the foundation needed to understand the components, structure, and workings of the ad/abaxial regulatory network directing basic plant growth and development. PMID:24076978

Evolutionary and Expression Analyses of the Apple Basic Leucine Zipper Transcription Factor Family

PubMed Central

Zhao, Jiao; Guo, Rongrong; Guo, Chunlei; Hou, Hongmin; Wang, Xiping; Gao, Hua

2016-01-01

Transcription factors (TFs) play essential roles in the regulatory networks controlling many developmental processes in plants. Members of the basic leucine (Leu) zipper (bZIP) TF family, which is unique to eukaryotes, are involved in regulating diverse processes, including flower and vascular development, seed maturation, stress signaling, and defense responses to pathogens. The bZIP proteins have a characteristic bZIP domain composed of a DNA-binding basic region and a Leu zipper dimerization region. In this study, we identified 112 apple (Malus domestica Borkh) bZIP TF-encoding genes, termed MdbZIP genes. Synteny analysis indicated that segmental and tandem duplication events, as well as whole genome duplication, have contributed to the expansion of the apple bZIP family. The family could be divided into 11 groups based on structural features of the encoded proteins, as well as on the phylogenetic relationship of the apple bZIP proteins to those of the model plant Arabidopsis thaliana (AtbZIP genes). Synteny analysis revealed that several paired MdbZIP genes and AtbZIP gene homologs were located in syntenic genomic regions. Furthermore, expression analyses of group A MdbZIP genes showed distinct expression levels in 10 different organs. Moreover, changes in these expression profiles in response to abiotic stress conditions and various hormone treatments identified MdbZIP genes that were responsive to high salinity and drought, as well as to different phytohormones. PMID:27066030

Basic leucine zipper family in barley: genome-wide characterization of members and expression analysis.

PubMed

Pourabed, Ehsan; Ghane Golmohamadi, Farzan; Soleymani Monfared, Peyman; Razavi, Seyed Morteza; Shobbar, Zahra-Sadat

2015-01-01

The basic leucine zipper (bZIP) family is one of the largest and most diverse transcription factors in eukaryotes participating in many essential plant processes. We identified 141 bZIP proteins encoded by 89 genes from the Hordeum vulgare genome. HvbZIPs were classified into 11 groups based on their DNA-binding motif. Amino acid sequence alignment of the HvbZIPs basic-hinge regions revealed some highly conserved residues within each group. The leucine zipper heptads were analyzed predicting their dimerization properties. 34 conserved motifs were identified outside the bZIP domain. Phylogenetic analysis indicated that major diversification within the bZIP family predated the monocot/dicot divergence, although intra-species duplication and parallel evolution seems to be occurred afterward. Localization of HvbZIPs on the barley chromosomes revealed that different groups have been distributed on seven chromosomes of barley. Six types of intron pattern were detected within the basic-hinge regions. Most of the detected cis-elements in the promoter and UTR sequences were involved in seed development or abiotic stress response. Microarray data analysis revealed differential expression pattern of HvbZIPs in response to ABA treatment, drought, and cold stresses and during barley grain development and germination. This information would be helpful for functional characterization of bZIP transcription factors in barley.

Genome-Wide Analysis of bZIP-Encoding Genes in Maize

PubMed Central

Wei, Kaifa; Chen, Juan; Wang, Yanmei; Chen, Yanhui; Chen, Shaoxiang; Lin, Yina; Pan, Si; Zhong, Xiaojun; Xie, Daoxin

2012-01-01

In plants, basic leucine zipper (bZIP) proteins regulate numerous biological processes such as seed maturation, flower and vascular development, stress signalling and pathogen defence. We have carried out a genome-wide identification and analysis of 125 bZIP genes that exist in the maize genome, encoding 170 distinct bZIP proteins. This family can be divided into 11 groups according to the phylogenetic relationship among the maize bZIP proteins and those in Arabidopsis and rice. Six kinds of intron patterns (a–f) within the basic and hinge regions are defined. The additional conserved motifs have been identified and present the group specificity. Detailed three-dimensional structure analysis has been done to display the sequence conservation and potential distribution of the bZIP domain. Further, we predict the DNA-binding pattern and the dimerization property on the basis of the characteristic features in the basic and hinge regions and the leucine zipper, respectively, which supports our classification greatly and helps to classify 26 distinct subfamilies. The chromosome distribution and the genetic analysis reveal that 58 ZmbZIP genes are located in the segmental duplicate regions in the maize genome, suggesting that the segment chromosomal duplications contribute greatly to the expansion of the maize bZIP family. Across the 60 different developmental stages of 11 organs, three apparent clusters formed represent three kinds of different expression patterns among the ZmbZIP gene family in maize development. A similar but slightly different expression pattern of bZIPs in two inbred lines displays that 22 detected ZmbZIP genes might be involved in drought stress. Thirteen pairs and 143 pairs of ZmbZIP genes show strongly negative and positive correlations in the four distinct fungal infections, respectively, based on the expression profile and Pearson's correlation coefficient analysis. PMID:23103471

Seasonal Abscisic Acid Signal and a Basic Leucine Zipper Transcription Factor, DkbZIP5, Regulate Proanthocyanidin Biosynthesis in Persimmon Fruit1[C][W][OA

PubMed Central

Akagi, Takashi; Katayama-Ikegami, Ayako; Kobayashi, Shozo; Sato, Akihiko; Kono, Atsushi; Yonemori, Keizo

2012-01-01

Proanthocyanidins (PAs) are secondary metabolites that contribute to plant protection and crop quality. Persimmon (Diospyros kaki) has a unique characteristic of accumulating large amounts of PAs, particularly in its fruit. Normal astringent-type and mutant nonastringent-type fruits show different PA accumulation patterns depending on the seasonal expression patterns of DkMyb4, which is a Myb transcription factor (TF) regulating many PA pathway genes in persimmon. In this study, attempts were made to identify the factors involved in DkMyb4 expression and the resultant PA accumulation in persimmon fruit. Treatment with abscisic acid (ABA) and an ABA biosynthesis inhibitor resulted in differential changes in the expression patterns of DkMyb4 and PA biosynthesis in astringent-type and nonastringent-type fruits depending on the development stage. To obtain an ABA-signaling TF, we isolated a full-length basic leucine zipper (bZIP) TF, DkbZIP5, which is highly expressed in persimmon fruit. We also showed that ectopic DkbZIP5 overexpression in persimmon calluses induced the up-regulation of DkMyb4 and the resultant PA biosynthesis. In addition, a detailed molecular characterization using the electrophoretic mobility shift assay and transient reporter assay indicated that DkbZIP5 recognized ABA-responsive elements in the promoter region of DkMyb4 and acted as a direct regulator of DkMyb4 in an ABA-dependent manner. These results suggest that ABA signals may be involved in PA biosynthesis in persimmon fruit via DkMyb4 activation by DkbZIP5. PMID:22190340

Cold-inducible transcription factor, CaCBF, is associated with a homeodomain leucine zipper protein in hot pepper (Capsicum annuum L.).

PubMed

Kim, Sihyun; An, Chung Sun; Hong, Young-Nam; Lee, Kwang-Woong

2004-12-31

C-Repeat/drought responsive element binding factor (CBF1/DREB1b) is a well known transcriptional activator that is induced at low temperature and in turn induces the CBF regulon (CBF-targeted genes). We have cloned and characterized two CBF1-like cDNAs, CaCBF1A and CaCBF1B, from hot pepper. CaCBF1A and CaCBF1B were not produced in response to mechanical wounding or abscisic acid but were induced by low-temperature stress at 4 degrees . When plants were returned to 25 degrees , their transcript levels of the CBF1-like genes decreased markedly within 40 min. Long-term exposure to chilling resulted in continuous expression of these genes. The critical temperature for induction of CaCBF1A was between 10 and 15 degrees . Low temperature led to its transcription in roots, stems, leaves, fruit without seeds, and apical meristems, and a monoclonal antibody against it revealed a significant increase in CaCBF1A protein by 4 h at 4 degrees . Two-hybrid screening led to the isolation of an homeodomain leucine zipper (HD-Zip) protein that interacts with CaCBF1B. Expression of HD-Zip was elevated by low temperature and drought.

A Ramie bZIP Transcription Factor BnbZIP2 Is Involved in Drought, Salt, and Heavy Metal Stress Response.

PubMed

Huang, Chengjian; Zhou, Jinghua; Jie, Yucheng; Xing, Hucheng; Zhong, Yingli; Yu, Weilin; She, Wei; Ma, Yushen; Liu, Zehang; Zhang, Ying

2016-12-01

bZIP transcription factors play key roles in plant growth, development, and stress signaling. A bZIP gene BnbZIP2 (GenBank accession number: KP642148) was cloned from ramie. BnbZIP2 has a 1416 base pair open reading frame, encoding a 471 amino acid protein containing a characteristic bZIP domain and a leucine zipper. BnbZIP2 shares high sequence similarity with bZIP factors from other plants. The BnbZIP2 protein is localized to both nuclei and cytoplasm. Transcripts of BnbZIP2 were found in various tissues in ramie, with significantly higher levels in female and male flowers. Its expression was induced by drought, high salinity, and abscisic acid treatments. Analysis of the cis-elements in promoters of BnbZIP2 identified cis-acting elements involved in growth, developmental processes, and a variety of stress responses. Transgenic Arabidopsis plants' overexpression of BnbZIP2 exhibited more sensitivity to drought and heavy metal Cd stress during seed germination, whereas more tolerance to high-salinity stress than the wild type during both seed germination and plant development. Thus, BnbZIP2 may act as a positive regulator in plants' response to high-salinity stress and be an important candidate gene for molecular breeding of salt-tolerant plants.

SlbZIP38, a Tomato bZIP Family Gene Downregulated by Abscisic Acid, Is a Negative Regulator of Drought and Salt Stress Tolerance

PubMed Central

Pan, Yanglu; Hu, Xin; Li, Chunyan; Xu, Xing; Su, Chenggang; Li, Jinhua; Song, Hongyuan; Zhang, Xingguo; Pan, Yu

2017-01-01

The basic leucine zipper (bZIP) transcription factors have crucial roles in plant stress responses. In this study, the bZIP family gene SlbZIP38 (GenBank accession No: XM004239373) was isolated from a tomato (Solanum lycopersicum cv. Ailsa Craig) mature leaf cDNA library. The DNA sequence of SlbZIP38 encodes a protein of 484 amino acids, including a highly conserved bZIP DNA-binding domain in the C-terminal region. We found that SlbZIP38 was differentially expressed in various organs of the tomato plant and was downregulated by drought, salt stress, and abscisic acid (ABA). However, overexpression of SlbZIP38 significantly decreased drought and salt stress tolerance in tomatoes (Ailsa Craig). The findings that SlbZIP38 overexpression reduced the chlorophyll and free proline content in leaves but increased the malondialdehyde content may explain the reduced drought and salt tolerance observed in these lines. These results suggest that SlbZIP38 is a negative regulator of drought and salt resistance that acts by modulating ABA signaling. PMID:29261143

Expression of a Truncated ATHB17 Protein in Maize Increases Ear Weight at Silking

PubMed Central

Creelman, Robert A.; Griffith, Cara; Ahrens, Jeffrey E.; Taylor, J. Philip; Murphy, Lesley R.; Manjunath, Siva; Thompson, Rebecca L.; Lingard, Matthew J.; Back, Stephanie L.; Larue, Huachun; Brayton, Bonnie R.; Burek, Amanda J.; Tiwari, Shiv; Adam, Luc; Morrell, James A.; Caldo, Rico A.; Huai, Qing; Kouadio, Jean-Louis K.; Kuehn, Rosemarie; Sant, Anagha M.; Wingbermuehle, William J.; Sala, Rodrigo; Foster, Matt; Kinser, Josh D.; Mohanty, Radha; Jiang, Dongming; Ziegler, Todd E.; Huang, Mingya G.; Kuriakose, Saritha V.; Skottke, Kyle; Repetti, Peter P.; Reuber, T. Lynne; Ruff, Thomas G.; Petracek, Marie E.; Loida, Paul J.

2014-01-01

ATHB17 (AT2G01430) is an Arabidopsis gene encoding a member of the α-subclass of the homeodomain leucine zipper class II (HD-Zip II) family of transcription factors. The ATHB17 monomer contains four domains common to all class II HD-Zip proteins: a putative repression domain adjacent to a homeodomain, leucine zipper, and carboxy terminal domain. However, it also possesses a unique N-terminus not present in other members of the family. In this study we demonstrate that the unique 73 amino acid N-terminus is involved in regulation of cellular localization of ATHB17. The ATHB17 protein is shown to function as a transcriptional repressor and an EAR-like motif is identified within the putative repression domain of ATHB17. Transformation of maize with an ATHB17 expression construct leads to the expression of ATHB17Δ113, a truncated protein lacking the first 113 amino acids which encodes a significant portion of the repression domain. Because ATHB17Δ113 lacks the repression domain, the protein cannot directly affect the transcription of its target genes. ATHB17Δ113 can homodimerize, form heterodimers with maize endogenous HD-Zip II proteins, and bind to target DNA sequences; thus, ATHB17Δ113 may interfere with HD-Zip II mediated transcriptional activity via a dominant negative mechanism. We provide evidence that maize HD-Zip II proteins function as transcriptional repressors and that ATHB17Δ113 relieves this HD-Zip II mediated transcriptional repression activity. Expression of ATHB17Δ113 in maize leads to increased ear size at silking and, therefore, may enhance sink potential. We hypothesize that this phenotype could be a result of modulation of endogenous HD-Zip II pathways in maize. PMID:24736658

Expression of a truncated ATHB17 protein in maize increases ear weight at silking.

PubMed

Rice, Elena A; Khandelwal, Abha; Creelman, Robert A; Griffith, Cara; Ahrens, Jeffrey E; Taylor, J Philip; Murphy, Lesley R; Manjunath, Siva; Thompson, Rebecca L; Lingard, Matthew J; Back, Stephanie L; Larue, Huachun; Brayton, Bonnie R; Burek, Amanda J; Tiwari, Shiv; Adam, Luc; Morrell, James A; Caldo, Rico A; Huai, Qing; Kouadio, Jean-Louis K; Kuehn, Rosemarie; Sant, Anagha M; Wingbermuehle, William J; Sala, Rodrigo; Foster, Matt; Kinser, Josh D; Mohanty, Radha; Jiang, Dongming; Ziegler, Todd E; Huang, Mingya G; Kuriakose, Saritha V; Skottke, Kyle; Repetti, Peter P; Reuber, T Lynne; Ruff, Thomas G; Petracek, Marie E; Loida, Paul J

2014-01-01

ATHB17 (AT2G01430) is an Arabidopsis gene encoding a member of the α-subclass of the homeodomain leucine zipper class II (HD-Zip II) family of transcription factors. The ATHB17 monomer contains four domains common to all class II HD-Zip proteins: a putative repression domain adjacent to a homeodomain, leucine zipper, and carboxy terminal domain. However, it also possesses a unique N-terminus not present in other members of the family. In this study we demonstrate that the unique 73 amino acid N-terminus is involved in regulation of cellular localization of ATHB17. The ATHB17 protein is shown to function as a transcriptional repressor and an EAR-like motif is identified within the putative repression domain of ATHB17. Transformation of maize with an ATHB17 expression construct leads to the expression of ATHB17Δ113, a truncated protein lacking the first 113 amino acids which encodes a significant portion of the repression domain. Because ATHB17Δ113 lacks the repression domain, the protein cannot directly affect the transcription of its target genes. ATHB17Δ113 can homodimerize, form heterodimers with maize endogenous HD-Zip II proteins, and bind to target DNA sequences; thus, ATHB17Δ113 may interfere with HD-Zip II mediated transcriptional activity via a dominant negative mechanism. We provide evidence that maize HD-Zip II proteins function as transcriptional repressors and that ATHB17Δ113 relieves this HD-Zip II mediated transcriptional repression activity. Expression of ATHB17Δ113 in maize leads to increased ear size at silking and, therefore, may enhance sink potential. We hypothesize that this phenotype could be a result of modulation of endogenous HD-Zip II pathways in maize.

In vivo binding of hot pepper bZIP transcription factor CabZIP1 to the G-box region of pathogenesis-related protein 1 promoter

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

Lee, Boo-Ja; Park, Chang-Jin; Kim, Sung-Kyu

2006-05-26

We find that salicylic acid and ethephon treatment in hot pepper increases the expression of a putative basic/leucine zipper (bZIP) transcription factor gene, CabZIP1. CabZIP1 mRNA is expressed ubiquitously in various organs. The green fluorescent protein-fused transcription factor, CabZIP1::GFP, can be specifically localized to the nucleus, an action that is consistent with the presence of a nuclear localization signal in its protein sequence. Transient overexpression of the CabZIP1 transcription factor results in an increase in PR-1 transcripts level in Nicotiana benthamiana leaves. Using chromatin immunoprecipitation, we demonstrate that CabZIP1 binds to the G-box elements in native promoter of the hotmore » pepper pathogenesis-related protein 1 (CaPR-1) gene in vivo. Taken together, our results suggest that CabZIP1 plays a role as a transcriptional regulator of the CaPR-1 gene.« less

Isolation and expression analysis of EcbZIP17 from different finger millet genotypes shows conserved nature of the gene.

PubMed

Chopperla, Ramakrishna; Singh, Sonam; Mohanty, Sasmita; Reddy, Nanja; Padaria, Jasdeep C; Solanke, Amolkumar U

2017-10-01

Basic leucine zipper (bZIP) transcription factors comprise one of the largest gene families in plants. They play a key role in almost every aspect of plant growth and development and also in biotic and abiotic stress tolerance. In this study, we report isolation and characterization of EcbZIP17 , a group B bZIP transcription factor from a climate smart cereal, finger millet ( Eleusine coracana L.). The genomic sequence of EcbZIP17 is 2662 bp long encompassing two exons and one intron with ORF of 1722 bp and peptide length of 573 aa. This gene is homologous to AtbZIP17 ( Arabidopsis ), ZmbZIP17 (maize) and OsbZIP60 (rice) which play a key role in endoplasmic reticulum (ER) stress pathway. In silico analysis confirmed the presence of basic leucine zipper (bZIP) and transmembrane (TM) domains in the EcbZIP17 protein. Allele mining of this gene in 16 different genotypes by Sanger sequencing revealed no variation in nucleotide sequence, including the 618 bp long intron. Expression analysis of EcbZIP17 under heat stress exhibited similar pattern of expression in all the genotypes across time intervals with highest upregulation after 4 h. The present study established the conserved nature of EcbZIP17 at nucleotide and expression level.

Genomic identification of bZIP family genes involved in drought and heat stresses in strawberry (Fragaria vesca)

USDA-ARS?s Scientific Manuscript database

Basic leucine zipper (bZIP) genes are known to play dominant roles in plant response to development signals, as well as abiotic or biotic stress stimuli. Fifty bZIP genes across the woodland strawberry (Fragaria vesca) genome were identified and analyzed. They can be divided into 10 clades according...

The Hairless Stem Phenotype of Cotton (Gossypium barbadense) Is Linked to a Copia-Like Retrotransposon Insertion in a Homeodomain-Leucine Zipper Gene (HD1)

PubMed Central

Ding, Mingquan; Ye, Wuwei; Lin, Lifeng; He, Shae; Du, Xiongming; Chen, Aiqun; Cao, Yuefen; Qin, Yuan; Yang, Fen; Jiang, Yurong; Zhang, Hua; Wang, Xiyin; Paterson, Andrew H.; Rong, Junkang

2015-01-01

Cotton (Gossypium) stem trichomes are mostly single cells that arise from stem epidermal cells. In this study, a homeodomain-leucine zipper gene (HD1) was found to cosegregate with the dominant trichome locus previously designated as T1 and mapped to chromosome 6. Characterization of HD1 orthologs revealed that the absence of stem trichomes in modern Gossypium barbadense varieties is linked to a large retrotransposon insertion in the ninth exon, 2565 bp downstream from the initial codon in the At subgenome HD1 gene (At-GbHD1). In both the At and Dt subgenomes, reduced transcription of GbHD1 genes is caused by this insertion. The disruption of At-HD1 further affects the expression of downstream GbMYB25 and GbHOX3 genes. Analyses of primitive cultivated accessions identified another retrotransposon insertion event in the sixth exon of At-GbHD1 that might predate the previously identified retrotransposon in modern varieties. Although both retrotransposon insertions results in similar phenotypic changes, the timing of these two retrotransposon insertion events fits well with our current understanding of the history of cotton speciation and dispersal. Taken together, the results of genetics mapping, gene expression and association analyses suggest that GbHD1 is an important component that controls stem trichome development and is a promising candidate gene for the T1 locus. The interspecific phenotypic difference in stem trichome traits also may be attributable to HD1 inactivation associated with retrotransposon insertion. PMID:26133897

Genome-Wide Identification and Expression Analysis of Homeodomain Leucine Zipper Subfamily IV (HDZ IV) Gene Family from Musa accuminata

PubMed Central

Pandey, Ashutosh; Misra, Prashant; Alok, Anshu; Kaur, Navneet; Sharma, Shivani; Lakhwani, Deepika; Asif, Mehar H.; Tiwari, Siddharth; Trivedi, Prabodh K.

2016-01-01

The homeodomain zipper family (HD-ZIP) of transcription factors is present only in plants and plays important role in the regulation of plant-specific processes. The subfamily IV of HDZ transcription factors (HD-ZIP IV) has primarily been implicated in the regulation of epidermal structure development. Though this gene family is present in all lineages of land plants, members of this gene family have not been identified in banana, which is one of the major staple fruit crops. In the present work, we identified 21 HDZIV encoding genes in banana by the computational analysis of banana genome resource. Our analysis suggested that these genes putatively encode proteins having all the characteristic domains of HDZIV transcription factors. The phylogenetic analysis of the banana HDZIV family genes further confirmed that after separation from a common ancestor, the banana, and poales lineages might have followed distinct evolutionary paths. Further, we conclude that segmental duplication played a major role in the evolution of banana HDZIV encoding genes. All the identified banana HDZIV genes expresses in different banana tissue, however at varying levels. The transcript levels of some of the banana HDZIV genes were also detected in banana fruit pulp, suggesting their putative role in fruit attributes. A large number of genes of this family showed modulated expression under drought and salinity stress. Taken together, the present work lays a foundation for elucidation of functional aspects of the banana HDZIV encoding genes and for their possible use in the banana improvement programs. PMID:26870050

Basic leucine zipper domain transcription factors: the vanguards in plant immunity.

PubMed

Noman, Ali; Liu, Zhiqin; Aqeel, Muhammad; Zainab, Madiha; Khan, Muhammad Ifnan; Hussain, Ansar; Ashraf, Muhammad Furqan; Li, Xia; Weng, Yahong; He, Shuilin

2017-12-01

Regulation of spatio-temporal expression patterns of stress tolerance associated plant genes is an essential component of the stress responses. Eukaryotes assign a large amount of their genome to transcription with multiple transcription factors (TFs). Often, these transcription factors fit into outsized gene groups which, in several cases, exclusively belong to plants. Basic leucine zipper domain (bZIP) transcription factors regulate vital processes in plants and animals. In plants, bZIPs are implicated in numerous fundamental processes like seed development, energy balance, and responses to abiotic or biotic stresses. Systematic analysis of the information obtained over the last two decades disclosed a constitutive role of bZIPs against biotic stress. bZIP TFs are vital players in plant innate immunity due to their ability to regulate genes associated with PAMP-triggered immunity, effector-triggered immunity, and hormonal signaling networks. Expression analysis of studied bZIP genes suggests that exploration and functional characterization of novel bZIP TFs in planta is helpful in improving crop resistance against pathogens and environmental stresses. Our review focuses on major advancements in bZIP TFs and plant responses against different pathogens. The integration of genomics information with the functional studies provides new insights into the regulation of plant defense mechanisms and engineering crops with improved resistance to invading pathogens. Conclusively, succinct functions of bZIPs as positive or negative regulator mediate resistance to the plant pathogens and lay a foundation for understanding associated genes and TFs regulating different pathways. Moreover, bZIP TFs may offer a comprehensive transgenic gizmo for engineering disease resistance in plant breeding programs.

OsbZIP58, a basic leucine zipper transcription factor, regulates starch biosynthesis in rice endosperm.

PubMed

Wang, Jie-Chen; Xu, Heng; Zhu, Ying; Liu, Qiao-Quan; Cai, Xiu-Ling

2013-08-01

Starch composition and the amount in endosperm, both of which contribute dramatically to seed yield, cooking quality, and taste in cereals, are determined by a series of complex biochemical reactions. However, the mechanism regulating starch biosynthesis in cereal seeds is not well understood. This study showed that OsbZIP58, a bZIP transcription factor, is a key transcriptional regulator controlling starch synthesis in rice endosperm. OsbZIP58 was expressed mainly in endosperm during active starch synthesis. osbzip58 null mutants displayed abnormal seed morphology with altered starch accumulation in the white belly region and decreased amounts of total starch and amylose. Moreover, osbzip58 had a higher proportion of short chains and a lower proportion of intermediate chains of amylopectin. Furthermore, OsbZIP58 was shown to bind directly to the promoters of six starch-synthesizing genes, OsAGPL3, Wx, OsSSIIa, SBE1, OsBEIIb, and ISA2, and to regulate their expression. These findings indicate that OsbZIP58 functions as a key regulator of starch synthesis in rice seeds and provide new insights into seed quality control.

Overexpression of a wheat (Triticum aestivum L.) bZIP transcription factor gene, TabZIP6, decreased the freezing tolerance of transgenic Arabidopsis seedlings by down-regulating the expression of CBFs.

PubMed

Cai, Wangting; Yang, Yaling; Wang, Weiwei; Guo, Guangyan; Liu, Wei; Bi, Caili

2018-03-01

The basic leucine zipper (bZIP) proteins play important roles against abiotic stress in plants, including cold stress. However, most bZIPs involved in plant freezing tolerance are positive regulators. Only a few bZIPs function negatively in cold stress response. In this study, TabZIP6, a Group C bZIP transcription factor gene from common wheat (Triticum aestivum L.), was cloned and characterized. The transcript of TabZIP6 was strongly induced by cold treatment (4 °C). TabZIP6 is a nuclear-localized protein with transcriptional activation activity. Arabidopsis plants overexpressing TabZIP6 showed decreased tolerance to freezing stress. Microarray as well as quantitative real-time PCR (qRT-PCR) analysis showed that CBFs and some key COR genes, including COR47 and COR15B, were down-regulated by cold treatment in TabZIP6-overexpressing Arabidopsis lines. TabZIP6 was capable of binding to the G-box motif and the CBF1 and CBF3 promoters in yeast cells. A yeast two-hybrid assay revealed that TabZIP6, as well as the other two Group S bZIP proteins involved in cold stress tolerance in wheat, Wlip19 and TaOBF1, can form homodimers by themselves and heterodimers with each other. These results suggest that TabZIP6 may function negatively in the cold stress response by binding to the promoters of CBFs, and thereby decreasing the expression of downstream COR genes in TabZIP6-overexpressing Arabidopsis seedlings. Copyright © 2018. Published by Elsevier Masson SAS.

Functional Analysis of Maize Silk-Specific ZmbZIP25 Promoter.

PubMed

Li, Wanying; Yu, Dan; Yu, Jingjuan; Zhu, Dengyun; Zhao, Qian

2018-03-12

ZmbZIP25 ( Zea mays bZIP (basic leucine zipper) transcription factor 25) is a function-unknown protein that belongs to the D group of the bZIP transcription factor family. RNA-seq data showed that the expression of ZmbZIP25 was tissue-specific in maize silks, and this specificity was confirmed by RT-PCR (reverse transcription-polymerase chain reaction). In situ RNA hybridization showed that ZmbZIP25 was expressed exclusively in the xylem of maize silks. A 5' RACE (rapid amplification of cDNA ends) assay identified an adenine residue as the transcription start site of the ZmbZIP25 gene. To characterize this silk-specific promoter, we isolated and analyzed a 2450 bp (from -2083 to +367) and a 2600 bp sequence of ZmbZIP25 (from -2083 to +517, the transcription start site was denoted +1). Stable expression assays in Arabidopsis showed that the expression of the reporter gene GUS driven by the 2450 bp ZmbZIP25 5'-flanking fragment occurred exclusively in the papillae of Arabidopsis stigmas. Furthermore, transient expression assays in maize indicated that GUS and GFP expression driven by the 2450 bp ZmbZIP25 5'-flanking sequences occurred only in maize silks and not in other tissues. However, no GUS or GFP expression was driven by the 2600 bp ZmbZIP25 5'-flanking sequences in either stable or transient expression assays. A series of deletion analyses of the 2450 bp ZmbZIP25 5'-flanking sequence was performed in transgenic Arabidopsis plants, and probable elements prediction analysis revealed the possible presence of negative regulatory elements within the 161 bp region from -1117 to -957 that were responsible for the specificity of the ZmbZIP25 5'-flanking sequence.

Functional Analysis of Maize Silk-Specific ZmbZIP25 Promoter

PubMed Central

Li, Wanying; Yu, Dan; Yu, Jingjuan; Zhu, Dengyun; Zhao, Qian

2018-01-01

ZmbZIP25 (Zea mays bZIP (basic leucine zipper) transcription factor 25) is a function-unknown protein that belongs to the D group of the bZIP transcription factor family. RNA-seq data showed that the expression of ZmbZIP25 was tissue-specific in maize silks, and this specificity was confirmed by RT-PCR (reverse transcription-polymerase chain reaction). In situ RNA hybridization showed that ZmbZIP25 was expressed exclusively in the xylem of maize silks. A 5′ RACE (rapid amplification of cDNA ends) assay identified an adenine residue as the transcription start site of the ZmbZIP25 gene. To characterize this silk-specific promoter, we isolated and analyzed a 2450 bp (from −2083 to +367) and a 2600 bp sequence of ZmbZIP25 (from −2083 to +517, the transcription start site was denoted +1). Stable expression assays in Arabidopsis showed that the expression of the reporter gene GUS driven by the 2450 bp ZmbZIP25 5′-flanking fragment occurred exclusively in the papillae of Arabidopsis stigmas. Furthermore, transient expression assays in maize indicated that GUS and GFP expression driven by the 2450 bp ZmbZIP25 5′-flanking sequences occurred only in maize silks and not in other tissues. However, no GUS or GFP expression was driven by the 2600 bp ZmbZIP25 5′-flanking sequences in either stable or transient expression assays. A series of deletion analyses of the 2450 bp ZmbZIP25 5′-flanking sequence was performed in transgenic Arabidopsis plants, and probable elements prediction analysis revealed the possible presence of negative regulatory elements within the 161 bp region from −1117 to −957 that were responsible for the specificity of the ZmbZIP25 5′-flanking sequence. PMID:29534529

Expression of a grape (Vitis vinifera) bZIP transcription factor, VlbZIP36, in Arabidopsis thaliana confers tolerance of drought stress during seed germination and seedling establishment.

PubMed

Tu, Mingxing; Wang, Xianhang; Feng, Tongying; Sun, Xiaomeng; Wang, Yaqiong; Huang, Li; Gao, Min; Wang, Yuejin; Wang, Xiping

2016-11-01

Drought is one of the most serious factors that limit agricultural productivity and there is considerable interest in understanding the molecular bases of drought responses and their regulation. While numbers of basic leucine zipper (bZIP) transcription factors (TFs) are known to play key roles in response of plants to various abiotic stresses, only a few group K bZIP TFs have been functionally characterized in the context of stress signaling. In this study, we characterized the expression of the grape (Vitis vinifera) group K bZIP gene, VlbZIP36, and found evidence for its involvement in response to drought and the stress-associated phytohormone abscisic acid (ABA). Transgenic Arabidopsis thaliana lines over-expressing VlbZIP36 under the control of a constitutive promoter showed enhanced dehydration tolerance during the seed germination stage, as well as in the seedling and mature plant stages. The results indicated that VlbZIP36 plays a role in drought tolerance by improving the water status, through limiting water loss, and mitigating cellular damage. The latter was evidenced by reduced cell death, lower electrolyte leakage in the transgenic plants, as well as by increased activities of antioxidant enzymes. We concluded that VlbZIP36 enhances drought tolerance through the transcriptional regulation of ABA-/stress-related genes. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Genome-Wide Identification and Structural Analysis of bZIP Transcription Factor Genes in Brassica napus.

PubMed

Zhou, Yan; Xu, Daixiang; Jia, Ledong; Huang, Xiaohu; Ma, Guoqiang; Wang, Shuxian; Zhu, Meichen; Zhang, Aoxiang; Guan, Mingwei; Lu, Kun; Xu, Xinfu; Wang, Rui; Li, Jiana; Qu, Cunmin

2017-10-24

The basic region/leucine zipper motif (bZIP) transcription factor family is one of the largest families of transcriptional regulators in plants. bZIP genes have been systematically characterized in some plants, but not in rapeseed ( Brassica napus ). In this study, we identified 247 BnbZIP genes in the rapeseed genome, which we classified into 10 subfamilies based on phylogenetic analysis of their deduced protein sequences. The BnbZIP genes were grouped into functional clades with Arabidopsis genes with similar putative functions, indicating functional conservation. Genome mapping analysis revealed that the BnbZIPs are distributed unevenly across all 19 chromosomes, and that some of these genes arose through whole-genome duplication and dispersed duplication events. All expression profiles of 247 bZIP genes were extracted from RNA-sequencing data obtained from 17 different B . napus ZS11 tissues with 42 various developmental stages. These genes exhibited different expression patterns in various tissues, revealing that these genes are differentially regulated. Our results provide a valuable foundation for functional dissection of the different BnbZIP homologs in B . napus and its parental lines and for molecular breeding studies of bZIP genes in B . napus .

Genome-Wide Identification and Structural Analysis of bZIP Transcription Factor Genes in Brassica napus

PubMed Central

Zhou, Yan; Xu, Daixiang; Jia, Ledong; Huang, Xiaohu; Ma, Guoqiang; Wang, Shuxian; Zhu, Meichen; Zhang, Aoxiang; Guan, Mingwei; Xu, Xinfu; Wang, Rui; Li, Jiana

2017-01-01

The basic region/leucine zipper motif (bZIP) transcription factor family is one of the largest families of transcriptional regulators in plants. bZIP genes have been systematically characterized in some plants, but not in rapeseed (Brassica napus). In this study, we identified 247 BnbZIP genes in the rapeseed genome, which we classified into 10 subfamilies based on phylogenetic analysis of their deduced protein sequences. The BnbZIP genes were grouped into functional clades with Arabidopsis genes with similar putative functions, indicating functional conservation. Genome mapping analysis revealed that the BnbZIPs are distributed unevenly across all 19 chromosomes, and that some of these genes arose through whole-genome duplication and dispersed duplication events. All expression profiles of 247 bZIP genes were extracted from RNA-sequencing data obtained from 17 different B. napus ZS11 tissues with 42 various developmental stages. These genes exhibited different expression patterns in various tissues, revealing that these genes are differentially regulated. Our results provide a valuable foundation for functional dissection of the different BnbZIP homologs in B. napus and its parental lines and for molecular breeding studies of bZIP genes in B. napus. PMID:29064393

Genome-wide characterization and analysis of bZIP transcription factor gene family related to abiotic stress in cassava.

PubMed

Hu, Wei; Yang, Hubiao; Yan, Yan; Wei, Yunxie; Tie, Weiwei; Ding, Zehong; Zuo, Jiao; Peng, Ming; Li, Kaimian

2016-03-07

The basic leucine zipper (bZIP) transcription factor family plays crucial roles in various aspects of biological processes. Currently, no information is available regarding the bZIP family in the important tropical crop cassava. Herein, 77 bZIP genes were identified from cassava. Evolutionary analysis indicated that MebZIPs could be divided into 10 subfamilies, which was further supported by conserved motif and gene structure analyses. Global expression analysis suggested that MebZIPs showed similar or distinct expression patterns in different tissues between cultivated variety and wild subspecies. Transcriptome analysis of three cassava genotypes revealed that many MebZIP genes were activated by drought in the root of W14 subspecies, indicating the involvement of these genes in the strong resistance of cassava to drought. Expression analysis of selected MebZIP genes in response to osmotic, salt, cold, ABA, and H2O2 suggested that they might participate in distinct signaling pathways. Our systematic analysis of MebZIPs reveals constitutive, tissue-specific and abiotic stress-responsive candidate MebZIP genes for further functional characterization in planta, yields new insights into transcriptional regulation of MebZIP genes, and lays a foundation for understanding of bZIP-mediated abiotic stress response.

Crosstalk between Two bZIP Signaling Pathways Orchestrates Salt-Induced Metabolic Reprogramming in Arabidopsis Roots

PubMed Central

Hartmann, Laura; Pedrotti, Lorenzo; Weiste, Christoph; Fekete, Agnes; Schierstaedt, Jasper; Göttler, Jasmin; Kempa, Stefan; Krischke, Markus; Dietrich, Katrin; Mueller, Martin J.; Vicente-Carbajosa, Jesus; Hanson, Johannes; Dröge-Laser, Wolfgang

2015-01-01

Soil salinity increasingly causes crop losses worldwide. Although roots are the primary targets of salt stress, the signaling networks that facilitate metabolic reprogramming to induce stress tolerance are less understood than those in leaves. Here, a combination of transcriptomic and metabolic approaches was performed in salt-treated Arabidopsis thaliana roots, which revealed that the group S1 basic leucine zipper transcription factors bZIP1 and bZIP53 reprogram primary C- and N-metabolism. In particular, gluconeogenesis and amino acid catabolism are affected by these transcription factors. Importantly, bZIP1 expression reflects cellular stress and energy status in roots. In addition to the well-described abiotic stress response pathway initiated by the hormone abscisic acid (ABA) and executed by SnRK2 (Snf1-RELATED-PROTEIN-KINASE2) and AREB-like bZIP factors, we identify a structurally related ABA-independent signaling module consisting of SnRK1s and S1 bZIPs. Crosstalk between these signaling pathways recruits particular bZIP factor combinations to establish at least four distinct gene expression patterns. Understanding this signaling network provides a framework for securing future crop productivity. PMID:26276836

Genome-wide analyses of the bZIP family reveal their involvement in the development, ripening and abiotic stress response in banana

PubMed Central

Hu, Wei; Wang, Lianzhe; Tie, Weiwei; Yan, Yan; Ding, Zehong; Liu, Juhua; Li, Meiying; Peng, Ming; Xu, Biyu; Jin, Zhiqiang

2016-01-01

The leucine zipper (bZIP) transcription factors play important roles in multiple biological processes. However, less information is available regarding the bZIP family in the important fruit crop banana. In this study, 121 bZIP transcription factor genes were identified in the banana genome. Phylogenetic analysis showed that MabZIPs were classified into 11 subfamilies. The majority of MabZIP genes in the same subfamily shared similar gene structures and conserved motifs. The comprehensive transcriptome analysis of two banana genotypes revealed the differential expression patterns of MabZIP genes in different organs, in various stages of fruit development and ripening, and in responses to abiotic stresses, including drought, cold, and salt. Interaction networks and co-expression assays showed that group A MabZIP-mediated networks participated in various stress signaling, which was strongly activated in Musa ABB Pisang Awak. This study provided new insights into the complicated transcriptional control of MabZIP genes and provided robust tissue-specific, development-dependent, and abiotic stress-responsive candidate MabZIP genes for potential applications in the genetic improvement of banana cultivars. PMID:27445085

Bioinformatic Analyses of Subgroup-A Members of the Wheat bZIP Transcription Factor Family and Functional Identification of TabZIP174 Involved in Drought Stress Response

PubMed Central

Li, Xueyin; Feng, Biane; Zhang, Fengjie; Tang, Yimiao; Zhang, Liping; Ma, Lingjian; Zhao, Changping; Gao, Shiqing

2016-01-01

Extensive studies in Arabidopsis and rice have demonstrated that Subgroup-A members of the bZIP transcription factor family play important roles in plant responses to multiple abiotic stresses. Although common wheat (Triticum aestivum) is one of the most widely cultivated and consumed food crops in the world, there are limited investigations into Subgroup A of the bZIP family in wheat. In this study, we performed bioinformatic analyses of the 41 Subgroup-A members of the wheat bZIP family. Phylogenetic and conserved motif analyses showed that most of the Subgroup-A bZIP proteins involved in abiotic stress responses of wheat, Arabidopsis, and rice clustered in Clade A1 of the phylogenetic tree, and shared a majority of conserved motifs, suggesting the potential importance of Clade-A1 members in abiotic stress responses. Gene structure analysis showed that TabZIP genes with close phylogenetic relationships tended to possess similar exon–intron compositions, and the positions of introns in the hinge regions of the bZIP domains were highly conserved, whereas introns in the leucine zipper regions were at variable positions. Additionally, eleven groups of homologs and two groups of tandem paralogs were also identified in Subgroup A of the wheat bZIP family. Expression profiling analysis indicated that most Subgroup-A TabZIP genes were responsive to abscisic acid and various abiotic stress treatments. TabZIP27, TabZIP74, TabZIP138, and TabZIP174 proteins were localized in the nucleus of wheat protoplasts, whereas TabZIP9-GFP fusion protein was simultaneously present in the nucleus, cytoplasm, and cell membrane. Transgenic Arabidopsis overexpressing TabZIP174 displayed increased seed germination rates and primary root lengths under drought treatments. Overexpression of TabZIP174 in transgenic Arabidopsis conferred enhanced drought tolerance, and transgenic plants exhibited lower water loss rates, higher survival rates, higher proline, soluble sugar, and leaf chlorophyll

N-terminal segments modulate the α-helical propensities of the intrinsically disordered basic regions of bZIP proteins.

PubMed

Das, Rahul K; Crick, Scott L; Pappu, Rohit V

2012-02-17

Basic region leucine zippers (bZIPs) are modular transcription factors that play key roles in eukaryotic gene regulation. The basic regions of bZIPs (bZIP-bRs) are necessary and sufficient for DNA binding and specificity. Bioinformatic predictions and spectroscopic studies suggest that unbound monomeric bZIP-bRs are uniformly disordered as isolated domains. Here, we test this assumption through a comparative characterization of conformational ensembles for 15 different bZIP-bRs using a combination of atomistic simulations and circular dichroism measurements. We find that bZIP-bRs have quantifiable preferences for α-helical conformations in their unbound monomeric forms. This helicity varies from one bZIP-bR to another despite a significant sequence similarity of the DNA binding motifs (DBMs). Our analysis reveals that intramolecular interactions between DBMs and eight-residue segments directly N-terminal to DBMs are the primary modulators of bZIP-bR helicities. We test the accuracy of this inference by designing chimeras of bZIP-bRs to have either increased or decreased overall helicities. Our results yield quantitative insights regarding the relationship between sequence and the degree of intrinsic disorder within bZIP-bRs, and might have general implications for other intrinsically disordered proteins. Understanding how natural sequence variations lead to modulation of disorder is likely to be important for understanding the evolution of specificity in molecular recognition through intrinsically disordered regions (IDRs). Copyright © 2011 Elsevier Ltd. All rights reserved.

Expression Profile Analysis of Zinc Transporters (ZIP4, ZIP9, ZIP11, ZnT9) in Gliomas and their Correlation with IDH1 Mutation Status.

PubMed

Kang, Xing; Chen, Rong; Zhang, Jie; Li, Gang; Dai, Peng-Gao; Chen, Chao; Wang, Hui-Juan

2015-01-01

Zinc transporters have been considered as essential regulators in many cancers; however, their mechanisms remain unknown, especially in gliomas. Isocitrate dehydrogenase 1(IDH1) mutation is crucial to glioma. This study aimed to investigate whether zinc transporters are correlated with glioma grade and IDH1 mutation status. IDH1 mutation status and mRNA expression of four zinc transporters (ZIP4, ZIP9, ZIP11, and ZnT9) were determined by subjecting a panel of 74 glioma tissue samples to quantitative real-time PCR and pyrosequencing. The correlations between the expression levels of these zinc transporter genes and the grade of glioma, as well as IDH1 mutation status, were investigated. Among the four zinc transporter genes, high ZIP4 expression and low ZIP11 expression were significantly associated with higher grade (grades III and IV) tumors compared with lower grade (grades I and II) counterparts (p<0.0001). However, only ZIP11 exhibited weak correlation with IDH1 mutation status (p=0.045). Samples with mutations in IDH1 displayed higher ZIP11 expression than those without IDH1 mutations. This finding indicated that zinc transporters may interact with IDH1 mutation by direct modulation or action in some shared pathways or genes to promote the development of glioma. Zinc transporters may play an important role in glioma. ZIP4 and ZIP11 are promising molecular diagnostic markers and novel therapeutic targets. Nevertheless, the detailed biological function of zinc transporters and the mechanism of the potential interaction between ZIP11 and IDH1 mutation in gliomagenesis should be further investigated.

Increasing the affinity of selective bZIP-binding peptides through surface residue redesign.

PubMed

Kaplan, Jenifer B; Reinke, Aaron W; Keating, Amy E

2014-07-01

The coiled-coil dimer is a prevalent protein interaction motif that is important for many cellular processes. The basic leucine-zipper (bZIP) transcription factors are one family of proteins for which coiled-coil mediated dimerization is essential for function, and misregulation of bZIPs can lead to disease states including cancer. This makes coiled coils attractive protein-protein interaction targets to disrupt using engineered molecules. Previous work designing peptides to compete with native coiled-coil interactions focused primarily on designing the core residues of the interface to achieve affinity and specificity. However, folding studies on the model bZIP GCN4 show that coiled-coil surface residues also contribute to binding affinity. Here we extend a prior study in which peptides were designed to bind tightly and specifically to representative members of each of 20 human bZIP families. These "anti-bZIP" peptides were designed with an emphasis on target-binding specificity, with contributions to design-target specificity and affinity engineered considering only the coiled-coil core residues. High-throughput testing using peptide arrays indicated many successes. We have now measured the binding affinities and specificities of anti-bZIPs that bind to FOS, XBP1, ATF6, and CREBZF in solution and tested whether redesigning the surface residues can increase design-target affinity. Incorporating residues that favor helix formation into the designs increased binding affinities in all cases, providing low-nanomolar binders of each target. However, changes in surface electrostatic interactions sometimes changed the binding specificity of the designed peptides. © 2014 The Protein Society.

The industrial water footprint of zippers.

PubMed

Zhang, Yin; Wu, Xiong Ying; Wang, Lai Li; Ding, Xue Mei

2014-01-01

Industrial production of apparel consumes large quantity of freshwater and discharges effluents that intensify the problem of freshwater shortage and water pollution. The industrial water footprint (IWF) of a piece of apparel includes the water footprint (WF) of the fabric, apparel accessories (e.g. zipper, fastener, sewing thread) and industrial production processes. The objective of this paper is to carry out a pilot study on IWF accounting for three kinds of typical zipper (i.e. metal zipper, polyethylene terephthalate (PET) zipper and polyoxymethylene copolymer (Co-POM) zipper) that are commonly used for apparel production. The results reveal that product output exerts a remarkable influence on zipper's average IWF. Metal zipper has the largest IWF and followed by Co-POM zipper and PET zipper. Painting, dyeing and primary processing are the top three water-consuming processes and contribute about 90% of the zipper's IWF. Painting consumes the largest amount of freshwater among all processes and occupies more than 50% of the zipper's IWF. In addition, the grey water footprint (WFgrey) provides the greatest contribution, more than 80%, to the zipper's IWF. Based on these results, this paper also provides several strategies aimed at water economization and pollution reduction during industrial production of zipper.

Genome-wide analysis and expression profile of the bZIP transcription factor gene family in grapevine (Vitis vinifera)

PubMed Central

2014-01-01

Background Basic leucine zipper (bZIP) transcription factor gene family is one of the largest and most diverse families in plants. Current studies have shown that the bZIP proteins regulate numerous growth and developmental processes and biotic and abiotic stress responses. Nonetheless, knowledge concerning the specific expression patterns and evolutionary history of plant bZIP family members remains very limited. Results We identified 55 bZIP transcription factor-encoding genes in the grapevine (Vitis vinifera) genome, and divided them into 10 groups according to the phylogenetic relationship with those in Arabidopsis. The chromosome distribution and the collinearity analyses suggest that expansion of the grapevine bZIP (VvbZIP) transcription factor family was greatly contributed by the segment/chromosomal duplications, which may be associated with the grapevine genome fusion events. Nine intron/exon structural patterns within the bZIP domain and the additional conserved motifs were identified among all VvbZIP proteins, and showed a high group-specificity. The predicted specificities on DNA-binding domains indicated that some highly conserved amino acid residues exist across each major group in the tree of land plant life. The expression patterns of VvbZIP genes across the grapevine gene expression atlas, based on microarray technology, suggest that VvbZIP genes are involved in grapevine organ development, especially seed development. Expression analysis based on qRT-PCR indicated that VvbZIP genes are extensively involved in drought- and heat-responses, with possibly different mechanisms. Conclusions The genome-wide identification, chromosome organization, gene structures, evolutionary and expression analyses of grapevine bZIP genes provide an overall insight of this gene family and their potential involvement in growth, development and stress responses. This will facilitate further research on the bZIP gene family regarding their evolutionary history and

Molecular cloning and characterization of a tomato cDNA encoding a systemically wound-inducible bZIP DNA-binding protein

NASA Technical Reports Server (NTRS)

Stankovic, B.; Vian, A.; Henry-Vian, C.; Davies, E.

2000-01-01

Localized wounding of one leaf in intact tomato (Lycopersicon esculentum Mill.) plants triggers rapid systemic transcriptional responses that might be involved in defense. To better understand the mechanism(s) of intercellular signal transmission in wounded tomatoes, and to identify the array of genes systemically up-regulated by wounding, a subtractive cDNA library for wounded tomato leaves was constructed. A novel cDNA clone (designated LebZIP1) encoding a DNA-binding protein was isolated and identified. This clone appears to be encoded by a single gene, and belongs to the family of basic leucine zipper domain (bZIP) transcription factors shown to be up-regulated by cold and dark treatments. Analysis of the mRNA levels suggests that the transcript for LebZIP1 is both organ-specific and up-regulated by wounding. In wounded wild-type tomatoes, the LebZIP1 mRNA levels in distant tissue were maximally up-regulated within only 5 min following localized wounding. Exogenous abscisic acid (ABA) prevented the rapid wound-induced increase in LebZIP1 mRNA levels, while the basal levels of LebZIP1 transcripts were higher in the ABA mutants notabilis (not), sitiens (sit), and flacca (flc), and wound-induced increases were greater in the ABA-deficient mutants. Together, these results suggest that ABA acts to curtail the wound-induced synthesis of LebZIP1 mRNA.

Salt and drought stress and ABA responses related to bZIP genes from V. radiata and V. angularis.

PubMed

Wang, Lanfen; Zhu, Jifeng; Li, Xiaoming; Wang, Shumin; Wu, Jing

2018-04-20

Mung bean and adzuki bean are warm-season legumes widely cultivated in China. However, bean production in major producing regions is limited by biotic and abiotic stress, such as drought and salt stress. Basic leucine zipper (bZIP) genes play key roles in responses to various biotic and abiotic stresses. However, only several bZIP genes involved in drought and salt stress in legumes, especially Vigna radiata and Vigna angularis, have been identified. In this study, we identified 54 and 50 bZIP proteins from whole-genome sequences of V. radiata and V. angularis, respectively. First, we comprehensively surveyed the characteristics of all bZIP genes, including their gene structure, chromosome distribution and motif composition. Phylogenetic trees showed that VrbZIP and VabZIP proteins were divided into ten clades comprising nine known and one unknown subgroup. The results of the nucleotide substitution rate of the orthologous gene pairs showed that bZIP proteins have undergone strong purifying selection: V. radiata and V. angularis diverged 1.25 million years ago (mya) to 9.20 mya (average of 4.95 mya). We also found that many cis-acting regulatory elements (CAREs) involved in abiotic stress and plant hormone responses were detected in the putative promoter regions of the bZIP genes. Finally, using the quantitative real-time PCR (qRT-PCR) method, we performed expression profiling of the bZIP genes in response to drought, salt and abscisic acid (ABA). We identified several bZIP genes that may be involved in drought and salt responses. Generally, our results provided useful and rich resources of VrbZIP and VabZIP genes for the functional characterization and understanding of bZIP transcription factors (TFs) in warm-season legumes. In addition, our results revealed important and interesting data - a subset of VrbZIP and VabZIP gene expression profiles in response to drought, salt and ABA stress. These results provide gene expression evidence for the selection of

High affinity receptor labeling based on basic leucine zipper domain peptides conjugated with pH-sensitive fluorescent dye: Visualization of AMPA-type glutamate receptor endocytosis in living neurons.

PubMed

Hayashi, Ayako; Asanuma, Daisuke; Kamiya, Mako; Urano, Yasuteru; Okabe, Shigeo

2016-01-01

Techniques to visualize receptor trafficking in living neurons are important, but currently available methods are limited in their labeling efficiency, specificity and reliability. Here we report a method for receptor labeling with a basic leucine zipper domain peptide (ZIP) and a binding cassette specific to ZIP. Receptors are tagged with a ZIP-binding cassette at their extracellular domain. Tagged receptors expressed in cultured cells were labeled with exogenously applied fluorescently labeled ZIP with low background and high affinity. To test if ZIP labeling is useful in monitoring endocytosis and intracellular trafficking, we next conjugated ZIP with a pH-sensitive dye RhP-M (ZIP-RhP-M). ZIP binding to its binding cassette was pH-resistant and RhP-M fluorescence dramatically increased in acidic environment. Thus AMPA-type glutamate receptors (AMPARs) labeled by ZIP-RhP-M can report receptor endocytosis and subsequent intracellular trafficking. Application of ZIP-RhP-M to cultured hippocampal neurons expressing AMPARs tagged with a ZIP-binding cassette resulted in appearance of fluorescent puncta in PSD-95-positive large spines, suggesting local endocytosis and acidification of AMPARs in individual mature spines. This spine pool of AMPARs in acidic environment was distinct from the early endosomes labeled by transferrin uptake. These results suggest that receptor labeling by ZIP-RhP-M is a useful technique for monitoring endocytosis and intracellular trafficking. This article is part of the Special Issue entitled 'Synaptopathy--from Biology to Therapy'. Copyright © 2015 Elsevier Ltd. All rights reserved.

DNA Methylation Influences Chlorogenic Acid Biosynthesis in Lonicera japonica by Mediating LjbZIP8 to Regulate Phenylalanine Ammonia-Lyase 2 Expression.

PubMed

Zha, Liangping; Liu, Shuang; Liu, Juan; Jiang, Chao; Yu, Shulin; Yuan, Yuan; Yang, Jian; Wang, Yaolong; Huang, Luqi

2017-01-01

The content of active compounds differ in buds and flowers of Lonicera japonica (FLJ) and L. japonica var. chinensis (rFLJ). Chlorogenic acid (CGAs) were major active compounds of L. japonica and regarded as measurements for quality evaluation. However, little is known concerning the formation of active compounds at the molecular level. We quantified the major CGAs in FLJ and rFLJ, and found the concentrations of CGAs were higher in the buds of rFLJ than those of FLJ. Further analysis of CpG methylation of CGAs biosynthesis genes showed differences between FLJ and rFLJ in the 5'-UTR of phenylalanine ammonia-lyase 2 ( PAL2 ). We identified 11 LjbZIP proteins and 24 rLjbZIP proteins with conserved basic leucine zipper domains, subcellular localization, and electrophoretic mobility shift assay showed that the transcription factor LjbZIP8 is a nuclear-localized protein that specifically binds to the G-box element of the LjPAL2 5'-UTR. Additionally, a transactivation assay and LjbZIP8 overexpression in transgenic tobacco indicated that LjbZIP8 could function as a repressor of transcription. Finally, treatment with 5-azacytidine decreased the transcription level of LjPAL2 and CGAs content in FLJ leaves. These results raise the possibility that DNA methylation might influence the recruitment of LjbZIP8, regulating PAL2 expression level and CGAs content in L. japonica .

HIV-1 Vpr Induces the Degradation of ZIP and sZIP, Adaptors of the NuRD Chromatin Remodeling Complex, by Hijacking DCAF1/VprBP

PubMed Central

Maudet, Claire; Sourisce, Adèle; Dragin, Loïc; Lahouassa, Hichem; Rain, Jean-Christophe; Bouaziz, Serge; Ramirez, Bertha Cécilia; Margottin-Goguet, Florence

2013-01-01

The Vpr protein from type 1 and type 2 Human Immunodeficiency Viruses (HIV-1 and HIV-2) is thought to inactivate several host proteins through the hijacking of the DCAF1 adaptor of the Cul4A ubiquitin ligase. Here, we identified two transcriptional regulators, ZIP and sZIP, as Vpr-binding proteins degraded in the presence of Vpr. ZIP and sZIP have been shown to act through the recruitment of the NuRD chromatin remodeling complex. Strikingly, chromatin is the only cellular fraction where Vpr is present together with Cul4A ubiquitin ligase subunits. Components of the NuRD complex and exogenous ZIP and sZIP were also associated with this fraction. Several lines of evidence indicate that Vpr induces ZIP and sZIP degradation by hijacking DCAF1: (i) Vpr induced a drastic decrease of exogenously expressed ZIP and sZIP in a dose-dependent manner, (ii) this decrease relied on the proteasome activity, (iii) ZIP or sZIP degradation was impaired in the presence of a DCAF1-binding deficient Vpr mutant or when DCAF1 expression was silenced. Vpr-mediated ZIP and sZIP degradation did not correlate with the growth-related Vpr activities, namely G2 arrest and G2 arrest-independent cytotoxicity. Nonetheless, infection with HIV-1 viruses expressing Vpr led to the degradation of the two proteins. Altogether our results highlight the existence of two host transcription factors inactivated by Vpr. The role of Vpr-mediated ZIP and sZIP degradation in the HIV-1 replication cycle remains to be deciphered. PMID:24116224

Exploring the bZIP transcription factor regulatory network in Neurospora crassa

PubMed Central

Tian, Chaoguang; Li, Jingyi; Glass, N. Louise

2011-01-01

Transcription factors (TFs) are key nodes of regulatory networks in eukaryotic organisms, including filamentous fungi such as Neurospora crassa. The 178 predicted DNA-binding TFs in N. crassa are distributed primarily among six gene families, which represent an ancient expansion in filamentous ascomycete genomes; 98 TF genes show detectable expression levels during vegetative growth of N. crassa, including 35 that show a significant difference in expression level between hyphae at the periphery versus hyphae in the interior of a colony. Regulatory networks within a species genome include paralogous TFs and their respective target genes (TF regulon). To investigate TF network evolution in N. crassa, we focused on the basic leucine zipper (bZIP) TF family, which contains nine members. We performed baseline transcriptional profiling during vegetative growth of the wild-type and seven isogenic, viable bZIP deletion mutants. We further characterized the regulatory network of one member of the bZIP family, NCU03905. NCU03905 encodes an Ap1-like protein (NcAp-1), which is involved in resistance to multiple stress responses, including oxidative and heavy metal stress. Relocalization of NcAp-1 from the cytoplasm to the nucleus was associated with exposure to stress. A comparison of the NcAp-1 regulon with Ap1-like regulons in Saccharomyces cerevisiae, Schizosaccharomyces pombe, Candida albicans and Aspergillus fumigatus showed both conservation and divergence. These data indicate how N. crassa responds to stress and provide information on pathway evolution. PMID:21081763

Exploring the bZIP transcription factor regulatory network in Neurospora crassa.

PubMed

Tian, Chaoguang; Li, Jingyi; Glass, N Louise

2011-03-01

Transcription factors (TFs) are key nodes of regulatory networks in eukaryotic organisms, including filamentous fungi such as Neurospora crassa. The 178 predicted DNA-binding TFs in N. crassa are distributed primarily among six gene families, which represent an ancient expansion in filamentous ascomycete genomes; 98 TF genes show detectable expression levels during vegetative growth of N. crassa, including 35 that show a significant difference in expression level between hyphae at the periphery versus hyphae in the interior of a colony. Regulatory networks within a species genome include paralogous TFs and their respective target genes (TF regulon). To investigate TF network evolution in N. crassa, we focused on the basic leucine zipper (bZIP) TF family, which contains nine members. We performed baseline transcriptional profiling during vegetative growth of the wild-type and seven isogenic, viable bZIP deletion mutants. We further characterized the regulatory network of one member of the bZIP family, NCU03905. NCU03905 encodes an Ap1-like protein (NcAp-1), which is involved in resistance to multiple stress responses, including oxidative and heavy metal stress. Relocalization of NcAp-1 from the cytoplasm to the nucleus was associated with exposure to stress. A comparison of the NcAp-1 regulon with Ap1-like regulons in Saccharomyces cerevisiae, Schizosaccharomyces pombe, Candida albicans and Aspergillus fumigatus showed both conservation and divergence. These data indicate how N. crassa responds to stress and provide information on pathway evolution.

Treatment of a delayed zipper injury.

PubMed

Mydlo, J H

2000-01-01

Penile zipper injuries have been reported occurring usually in the pediatric population, and occasionally in adults. Usually, the zipper can be dislodged with mineral oil or by breaking the median bar. When these attempts fail, a small elliptical incision may be used to remove the zipper and any devitalized tissue. Copyright 2000 S. Karger AG, Basel

DNA Methylation Influences Chlorogenic Acid Biosynthesis in Lonicera japonica by Mediating LjbZIP8 to Regulate Phenylalanine Ammonia-Lyase 2 Expression

PubMed Central

Zha, Liangping; Liu, Shuang; Liu, Juan; Jiang, Chao; Yu, Shulin; Yuan, Yuan; Yang, Jian; Wang, Yaolong; Huang, Luqi

2017-01-01

The content of active compounds differ in buds and flowers of Lonicera japonica (FLJ) and L. japonica var. chinensis (rFLJ). Chlorogenic acid (CGAs) were major active compounds of L. japonica and regarded as measurements for quality evaluation. However, little is known concerning the formation of active compounds at the molecular level. We quantified the major CGAs in FLJ and rFLJ, and found the concentrations of CGAs were higher in the buds of rFLJ than those of FLJ. Further analysis of CpG methylation of CGAs biosynthesis genes showed differences between FLJ and rFLJ in the 5′-UTR of phenylalanine ammonia-lyase 2 (PAL2). We identified 11 LjbZIP proteins and 24 rLjbZIP proteins with conserved basic leucine zipper domains, subcellular localization, and electrophoretic mobility shift assay showed that the transcription factor LjbZIP8 is a nuclear-localized protein that specifically binds to the G-box element of the LjPAL2 5′-UTR. Additionally, a transactivation assay and LjbZIP8 overexpression in transgenic tobacco indicated that LjbZIP8 could function as a repressor of transcription. Finally, treatment with 5-azacytidine decreased the transcription level of LjPAL2 and CGAs content in FLJ leaves. These results raise the possibility that DNA methylation might influence the recruitment of LjbZIP8, regulating PAL2 expression level and CGAs content in L. japonica. PMID:28740500

Zipper Connectors for Flexible Electronic Circuits

NASA Technical Reports Server (NTRS)

Barnes, Kevin N.

2003-01-01

Devices that look and function much like conventional zippers on clothing have been proposed as connectors for flexible electronic circuits. Heretofore, flexible electronic circuits have commonly included rigid connectors like those of conventional rigid electronic circuits. The proposed zipper connectors would make it possible to connect and disconnect flexible circuits quickly and easily. Moreover, the flexibility of zipper connectors would make them more (relative to rigid connectors) compatible with flexible circuits, so that the advantages of flexible circuitry could be realized more fully. Like a conventional zipper, a zipper according to the proposal would include teeth anchored on flexible tapes, a slider with a loosely attached clasp, a box at one end of the rows of mating teeth, and stops at the opposite ends. The tapes would be made of a plastic or other dielectric material. On each of the two mating sides of the zipper, metal teeth would alternate with dielectric (plastic) teeth, there being two metal teeth for each plastic one. When the zipper was closed, each metal tooth from one side would be in mechanical and electrical contact with a designated metal tooth from the other side, and these mating metal teeth would be electrically insulated from the next pair of mating metal teeth by an intervening plastic tooth. The metal teeth would be soldered or crimped to copper tabs. Wires or other conductors connected to electronic circuits would be soldered or crimped to the ends of the tabs opposite the teeth.

Bioinformatic analyses implicate the collaborating meiotic crossover/chiasma proteins Zip2, Zip3, and Spo22/Zip4 in ubiquitin labeling

PubMed Central

Perry, Jason; Kleckner, Nancy; Börner, G. Valentin

2005-01-01

Zip2 and Zip3 are meiosis-specific proteins that, in collaboration with several partners, act at the sites of crossover-designated, axis-associated recombinational interactions to mediate crossover/chiasma formation. Here, Spo22 (also called Zip4) is identified as a probable functional collaborator of Zip2/3. The molecular roles of Zip2, Zip3, and Spo22/Zip4 are unknown. All three proteins are part of a small evolutionary cohort comprising similar homologs in four related yeasts. Zip3 is shown to contain a RING finger whose structural features most closely match those of known ubiquitin E3s. Further, Zip3 exhibits major domainal homologies to Rad18, a known DNA-binding ubiquitin E3. Also described is an approach to the identification and mapping of repeated protein sequence motifs, Alignment Based Repeat Annotation (ABRA), that we have developed. When ABRA is applied to Zip2 and Spo22/Zip4, they emerge as a 14-blade WD40-like repeat protein and a 22-unit tetratricopeptide repeat protein, respectively. WD40 repeats of Cdc20, Cdh1, and Cdc16 and tetratricopeptide repeats of Cdc16, Cdc23, and Cdc27, all components of the anaphase-promoting complex, are also analyzed. These and other findings suggest that Zip2, Zip3, and Zip4 act together to mediate a process that involves Zip3-mediated ubiquitin labeling, potentially as a unique type of ubiquitin-conjugating complex. PMID:16314568

Evolution of the Class IV HD-Zip Gene Family in Streptophytes

PubMed Central

Zalewski, Christopher S.; Floyd, Sandra K.; Furumizu, Chihiro; Sakakibara, Keiko; Stevenson, Dennis W.; Bowman, John L.

2013-01-01

Class IV homeodomain leucine zipper (C4HDZ) genes are plant-specific transcription factors that, based on phenotypes in Arabidopsis thaliana, play an important role in epidermal development. In this study, we sampled all major extant lineages and their closest algal relatives for C4HDZ homologs and phylogenetic analyses result in a gene tree that mirrors land plant evolution with evidence for gene duplications in many lineages, but minimal evidence for gene losses. Our analysis suggests an ancestral C4HDZ gene originated in an algal ancestor of land plants and a single ancestral gene was present in the last common ancestor of land plants. Independent gene duplications are evident within several lineages including mosses, lycophytes, euphyllophytes, seed plants, and, most notably, angiosperms. In recently evolved angiosperm paralogs, we find evidence of pseudogenization via mutations in both coding and regulatory sequences. The increasing complexity of the C4HDZ gene family through the diversification of land plants correlates to increasing complexity in epidermal characters. PMID:23894141

Variation Analysis of Physiological Traits in Betula platyphylla Overexpressing TaLEA-ThbZIP Gene under Salt Stress

PubMed Central

Xiao, Zhenhai; Wang, Fuwei; Li, Shuchun; Zang, Lina; Zheng, Mi; Li, Ying; Qu, Guan-Zheng

2016-01-01

The aim of this study was to determine whether transgenic birch (Betula platyphylla) ectopic overexpressing a late embryogenesis abundant (LEA) gene and a basic leucine zipper (bZIP) gene from the salt-tolerant genus Tamarix (salt cedar) show increased tolerance to salt (NaCl) stress. Co-transfer of TaLEA and ThbZIP in birch under the control of two independent CaMV 35S promoters significantly enhanced salt stress. PCR and northern blot analyses indicated that the two genes were ectopically overexpressed in several dual-gene transgenic birch lines. We compared the effects of salt stress among three transgenic birch lines (L-4, L-5, and L-8) and wild type (WT). In all lines, the net photosynthesis values were higher before salt stress treatment than afterwards. After the salt stress treatment, the transgenic lines L-4 and L-8 showed higher values for photosynthetic traits, chlorophyll fluorescence, peroxidase and superoxide dismutase activities, and lower malondialdehyde and Na+ contents, compared with those in WT and L-5. These different responses to salt stress suggested that the transcriptional level of the TaLEA and ThbZIP genes differed among the transgenic lines, resulting in a variety of genetic and phenotypic effects. The results of this research can provide a theoretical basis for the genetic engineering of salt-tolerant trees. PMID:27802286

Curcumin differentially regulates endoplasmic reticulum stress through transcriptional corepressor SMILE (small heterodimer partner-interacting leucine zipper protein)-mediated inhibition of CREBH (cAMP responsive element-binding protein H).

PubMed

Misra, Jagannath; Chanda, Dipanjan; Kim, Don-kyu; Li, Tiangang; Koo, Seung-Hoi; Back, Sung-Hoon; Chiang, John Y L; Choi, Hueng-Sik

2011-12-09

Curcumin (diferuloylmethane), a major active component of turmeric (Curcuma longa), is a natural polyphenolic compound. Herein the effect of curcumin on endoplasmic reticulum (ER) stress responsive gene expression was investigated. We report that curcumin induces transcriptional corepressor small heterodimer partner-interacting leucine zipper protein (SMILE) gene expression through liver kinase B1 (LKB1)/adenosine monophosphate-activated kinase (AMPK) signaling pathway and represses ER stress-responsive gene transcription in an ER-bound transcription factor specific manner. cAMP responsive element-binding protein H (CREBH) and activating transcription factor 6 (ATF6) are both ER-bound bZIP family transcription factors that are activated upon ER stress. Of interest, we observed that both curcumin treatment and SMILE overexpression only represses CREBH-mediated transactivation of the target gene but not ATF6-mediated transactivation. Knockdown of endogenous SMILE significantly releases the inhibitory effect of curcumin on CREBH transactivation. Intrinsic repressive activity of SMILE is observed in the Gal4 fusion system, and the intrinsic repressive domain is mapped to the C terminus of SMILE spanning amino acid residues 203-269, corresponding to the basic region leucine zipper (bZIP) domain. In vivo interaction assay revealed that through its bZIP domain, SMILE interacts with CREBH and inhibits its transcriptional activity. Interestingly, we observed that SMILE does not interact with ATF6. Furthermore, competition between SMILE and the coactivator peroxisome proliferator-activated receptor α (PGC-1α) on CREBH transactivation has been demonstrated in vitro and in vivo. Finally, chromatin immunoprecipitation assays revealed that curcumin decreases the binding of PGC-1α and CREBH on target gene promoter in a SMILE-dependent manner. Overall, for the first time we suggest a novel phenomenon that the curcumin/LKB1/AMPK/SMILE/PGC1α pathway differentially regulates ER

HTLV-1 basic leucine zipper factor downregulates cyclin D1 expression via interactions with NF-κB.

PubMed

Ma, Yunyun; Zhang, Bo; Wang, Dong; Qian, Lili; Song, Xianmei; Wang, Xueyin; Yang, Chaokuan; Zhao, Guoqiang

2017-03-01

Human T cell leukemia virus type 1 (HTLV-1) is an oncogenic retrovirus. It can cause adult T cell leukemia (ATL) and other diseases. The HTLV-1 basic leucine zipper (bZIP) factor (HBZ), which is encoded by the minus-strand of the provirus, is expressed in all cases of ATL and involved in T cell proliferation. However, the exact mechanism underlying its growth-promoting activity is poorly understood. Herein, we demonstrated that HBZ suppressed cyclin D1 expression by inhibiting the nuclear factor (NF)-κB signaling pathway. Among the potential mechanisms of cyclin D1 inhibition mediated by HBZ, we found that HBZ suppressed cyclin D1 promoter activity. Luciferase assay analysis revealed that HBZ repressed cyclin D1 promoter activity by suppressing NF-κB‑driven transcription mediated by the p65 subunit. Using an immunoprecipitation assay, we found that HBZ could bind to p65, but not p50. Finally, we showed that HBZ selectively interacted with p65 via its AD+bZIP domains. By suppressing cyclin D1 expression, HBZ can alter cell cycle progression of HTLV-1-infected cells, which may be critical for oncogenesis.

The Arabidopsis bZIP11 transcription factor links low-energy signalling to auxin-mediated control of primary root growth

PubMed Central

Weiste, Christoph; Pedrotti, Lorenzo; Muralidhara, Prathibha; Ljung, Karin; Dröge-Laser, Wolfgang

2017-01-01

Plants have to tightly control their energy homeostasis to ensure survival and fitness under constantly changing environmental conditions. Thus, it is stringently required that energy-consuming stress-adaptation and growth-related processes are dynamically tuned according to the prevailing energy availability. The evolutionary conserved SUCROSE NON-FERMENTING1 RELATED KINASES1 (SnRK1) and the downstream group C/S1 basic leucine zipper (bZIP) transcription factors (TFs) are well-characterised central players in plants’ low-energy management. Nevertheless, mechanistic insights into plant growth control under energy deprived conditions remains largely elusive. In this work, we disclose the novel function of the low-energy activated group S1 bZIP11-related TFs as regulators of auxin-mediated primary root growth. Whereas transgenic gain-of-function approaches of these bZIPs interfere with the activity of the root apical meristem and result in root growth repression, root growth of loss-of-function plants show a pronounced insensitivity to low-energy conditions. Based on ensuing molecular and biochemical analyses, we propose a mechanistic model, in which bZIP11-related TFs gain control over the root meristem by directly activating IAA3/SHY2 transcription. IAA3/SHY2 is a pivotal negative regulator of root growth, which has been demonstrated to efficiently repress transcription of major auxin transport facilitators of the PIN-FORMED (PIN) gene family, thereby restricting polar auxin transport to the root tip and in consequence auxin-driven primary root growth. Taken together, our results disclose the central low-energy activated SnRK1-C/S1-bZIP signalling module as gateway to integrate information on the plant’s energy status into root meristem control, thereby balancing plant growth and cellular energy resources. PMID:28158182

The Arabidopsis bZIP11 transcription factor links low-energy signalling to auxin-mediated control of primary root growth.

PubMed

Weiste, Christoph; Pedrotti, Lorenzo; Selvanayagam, Jebasingh; Muralidhara, Prathibha; Fröschel, Christian; Novák, Ondřej; Ljung, Karin; Hanson, Johannes; Dröge-Laser, Wolfgang

2017-02-01

Plants have to tightly control their energy homeostasis to ensure survival and fitness under constantly changing environmental conditions. Thus, it is stringently required that energy-consuming stress-adaptation and growth-related processes are dynamically tuned according to the prevailing energy availability. The evolutionary conserved SUCROSE NON-FERMENTING1 RELATED KINASES1 (SnRK1) and the downstream group C/S1 basic leucine zipper (bZIP) transcription factors (TFs) are well-characterised central players in plants' low-energy management. Nevertheless, mechanistic insights into plant growth control under energy deprived conditions remains largely elusive. In this work, we disclose the novel function of the low-energy activated group S1 bZIP11-related TFs as regulators of auxin-mediated primary root growth. Whereas transgenic gain-of-function approaches of these bZIPs interfere with the activity of the root apical meristem and result in root growth repression, root growth of loss-of-function plants show a pronounced insensitivity to low-energy conditions. Based on ensuing molecular and biochemical analyses, we propose a mechanistic model, in which bZIP11-related TFs gain control over the root meristem by directly activating IAA3/SHY2 transcription. IAA3/SHY2 is a pivotal negative regulator of root growth, which has been demonstrated to efficiently repress transcription of major auxin transport facilitators of the PIN-FORMED (PIN) gene family, thereby restricting polar auxin transport to the root tip and in consequence auxin-driven primary root growth. Taken together, our results disclose the central low-energy activated SnRK1-C/S1-bZIP signalling module as gateway to integrate information on the plant's energy status into root meristem control, thereby balancing plant growth and cellular energy resources.

The bZIP dimer localizes at DNA full-sites where each basic region can alternately translocate and bind to subsites at the half-site.

PubMed

Chan, I-San; Al-Sarraj, Taufik; Shahravan, S Hesam; Fedorova, Anna V; Shin, Jumi A

2012-08-21

Crystal structures of the GCN4 bZIP (basic region/leucine zipper) with the AP-1 or CRE site show how each GCN4 basic region binds to a 4 bp cognate half-site as a single DNA target; however, this may not always fully describe how bZIP proteins interact with their target sites. Previously, we showed that the GCN4 basic region interacts with all 5 bp in half-site TTGCG (termed 5H-LR) and that 5H-LR comprises two 4 bp subsites, TTGC and TGCG, which individually are also target sites of the basic region. In this work, we explore how the basic region interacts with 5H-LR when the bZIP dimer localizes to full-sites. Using AMBER molecular modeling, we simulated GCN4 bZIP complexes with full-sites containing 5H-LR to investigate in silico the interface between the basic region and 5H-LR. We also performed in vitro investigation of bZIP-DNA interactions at a number of full-sites that contain 5H-LR versus either subsite: we analyzed results from DNase I footprinting and electrophoretic mobility shift assay (EMSA) and from EMSA titrations to quantify binding affinities. Our computational and experimental results together support a highly dynamic DNA-binding model: when a bZIP dimer localizes to its target full-site, the basic region can alternately recognize either subsite as a distinct target at 5H-LR and translocate between the subsites, potentially by sliding and hopping. This model provides added insights into how α-helical DNA-binding domains of transcription factors can localize to their gene regulatory sequences in vivo.

Mitochondrial AtTrxo1 is transcriptionally regulated by AtbZIP9 and AtAZF2 and affects seed germination under saline conditions

PubMed Central

Ortiz-Espín, Ana; Iglesias-Fernández, Raquel; Calderón, Aingeru; Carbonero, Pilar; Sevilla, Francisca

2017-01-01

Abstract Mitochondrial thioredoxin-o (AtTrxo1) was characterized and its expression examined in different organs of Arabidopsis thaliana. AtTrxo1 transcript levels were particularly high in dry seeds and cotyledons where they reached a maximum 36 h after imbibition with water, coinciding with 50% germination. Expression was lower in seeds germinating in 100 mM NaCl. To gain insight into the transcriptional regulation of the AtTrxo1 gene, a phylogenomic analysis was coupled with the screening of an arrayed library of Arabidopsis transcription factors in yeast. The basic leucine zipper AtbZIP9 and the zinc finger protein AZF2 were identified as putative transcriptional regulators. Transcript regulation of AtbZIP9 and AtAFZ2 during germination was compatible with the proposed role in transcriptional regulation of AtTrxo1. Transient over-expression of AtbZIP9 and AtAZF2 in Nicotiana benthamiana leaves demonstrated an activation effect of AtbZIP9 and a repressor effect of AtAZF2 on AtTrxo1 promoter-driven reporter expression. Although moderate concentrations of salt delayed germination in Arabidopsis wild-type seeds, those of two different AtTrxo1 knock-out mutants germinated faster and accumulated higher H2O2 levels than the wild-type. All these data indicate that AtTrxo1 has a role in redox homeostasis during seed germination under salt conditions. PMID:28184497

OsSLI1, a homeodomain containing transcription activator, involves abscisic acid related stress response in rice (Oryza sativa L.).

PubMed

Huang, Xi; Duan, Min; Liao, Jiakai; Yuan, Xi; Chen, Hui; Feng, Jiejie; Huang, Ji; Zhang, Hong-Sheng

2014-01-01

Homeodomain-leucine zipper type I (HD-Zip I) proteins are involved in the regulation of plant development and response to environmental stresses. In this study, OsSLI1 (Oryza sativa stress largely induced 1), encoding a member of the HD-Zip I subfamily, was isolated from rice. The expression of OsSLI1 was dramatically induced by multiple abiotic stresses and exogenous abscisic acid (ABA). In silico sequence analysis discovered several cis-acting elements including multiple ABREs (ABA-responsive element binding factors) in the upstream promoter region of OsSLI1. The OsSLI1-GFP fusion protein was localized in the nucleus of rice protoplast cells and the transcriptional activity of OsSLI1 was confirmed by the yeast hybrid system. Further, it was found that OsSLI1 expression was enhanced in an ABI5-Like1 (ABL1) deficiency rice mutant abl1 under stress conditions, suggesting that ABL1 probably negatively regulates OsSLI1 gene expression. Moreover, it was found that OsSLI1 was regulated in panicle development. Taken together, OsSLI1 may be a transcriptional activator regulating stress-responsive gene expression and panicle development in rice.

Genome-wide identification, expansion, and evolution analysis of homeobox genes and their expression profiles during root development in carrot.

PubMed

Que, Feng; Wang, Guang-Long; Li, Tong; Wang, Ya-Hui; Xu, Zhi-Sheng; Xiong, Ai-Sheng

2018-06-16

The homeobox gene family, a large family represented by transcription factors, has been implicated in secondary growth, early embryo patterning, and hormone response pathways in plants. However, reports about the information and evolutionary history of the homeobox gene family in carrot are limited. In the present study, a total of 130 homeobox family genes were identified in the carrot genome. Specific codomain and phylogenetic analyses revealed that the genes were classified into 14 subgroups. Whole genome and proximal duplication participated in the homeobox gene family expansion in carrot. Purifying selection also contributed to the evolution of carrot homeobox genes. In Gene Ontology (GO) analysis, most members of the HD-ZIP III and IV subfamilies were found to have a lipid binding (GO:0008289) term. Most HD-ZIP III and IV genes also harbored a steroidogenic acute regulatory protein-related lipid transfer (START) domain. These results suggested that the HD-ZIP III and IV subfamilies might be related to lipid transfer. Transcriptome and quantitative real-time PCR (RT-qPCR) data indicated that members of the WOX and KNOX subfamilies were likely implicated in carrot root development. Our study provided a useful basis for further studies on the complexity and function of the homeobox gene family in carrot.

Shear zone junctions: Of zippers and freeways

NASA Astrophysics Data System (ADS)

Passchier, Cees W.; Platt, John P.

2017-02-01

Ductile shear zones are commonly treated as straight high-strain domains with uniform shear sense and characteristic curved foliation trails, bounded by non-deforming wall rock. Many shear zones, however, are branched, and if movement on such branches is contemporaneous, the resulting shape can be complicated and lead to unusual shear sense arrangement and foliation geometries in the wall rock. For Y-shaped shear zone triple junctions with three joining branches and transport direction at a high angle to the branchline, only eight basic types of junction are thought to be stable and to produce significant displacement. The simplest type, called freeway junctions, have similar shear sense in all three branches. The other types show joining or separating behaviour of shear zone branches similar to the action of a zipper. Such junctions may have shear zone branches that join to form a single branch (closing zipper junction), or a single shear zone that splits to form two branches, (opening zipper junction). All categories of shear zone junctions show characteristic foliation patterns and deflection of markers in the wall rock. Closing zipper junctions are unusual, since they form a non-active zone with opposite deflection of foliations in the wall rock known as an extraction fault or wake. Shear zipper junctions can form domains of overprinting shear sense along their flanks. A small and large field example are given from NE Spain and Eastern Anatolia. The geometry of more complex, 3D shear zone junctions with slip parallel and oblique to the branchline is briefly discussed.

Abundance analysis of the supergiant stars HD 80057 and HD 80404 based on their UVES Spectra

NASA Astrophysics Data System (ADS)

Tanrıverdi, T.; Baştürk, Ö.

2016-08-01

This study presents elemental abundances of the early A-type supergiant HD 80057 and the late A-type supergiant HD 80404. High resolution and high signal-to-noise ratio spectra published by the UVES Paranal Observatory Project (Bagnulo et al., 2003) were analyzed to compute their elemental abundances using ATLAS9 (Kurucz, 1993; 2005; Sbordone et al., 2004). In our analysis we assumed local thermodynamic equilibrium. The atmospheric parameters of HD 80057 used in this study are from Firnstein and Przybilla (2012), and that of HD 80404 are derived from spectral energy distribution, ionization equilibria of Cr I/II and Fe I/II, the fits to the wings of Balmer and Paschen lines as Teff = 7700 ± 150 K and log g = 1.60 ± 0.15 (in cgs). The microturbulent velocities of HD 80057 and HD 80404 have been determined as 4.3 ± 0.1 and 2.2 ± 0.0 km s^-1, respectively. The rotational velocities are 15 ± 1 and 7 ± 2 km s^-1 and their macroturbulence velocities are 24 ± 2 and 2 ± 1 km s^1. We have given the abundances of 25 ions of 19 elements for HD 80057 and 36 ions of 25 elements for HD 80404. The abundances are close to solar values, except for some elements (Na, Sc, Ti, V, Ba, and Sr). We have found the metallicities [M/H] for HD 80057 and HD 80404 as -0.16 ± 0.24 and -0.04 ± 0.16 dex, respectively. The evolutionary status of these stars are discussed and their nitrogen-to-carbon (N/C) and nitrogen-to-oxygen (N/O) ratios show that they are in their blue supergiant phase before the red supergiant region.

The bZIP dimer localizes at DNA full-sites where each basic region can alternately translocate and bind to subsites at the half-site

PubMed Central

Chan, I-San; Al-Sarraj, Taufik; Shahravan, S. Hesam; Fedorova, Anna V.; Shin, Jumi A.

2012-01-01

Crystal structures of the GCN4 bZIP (basic region/leucine zipper) with the AP-1 or CRE site show how each GCN4 basic region binds to a 4-bp cognate half-site as a single DNA target; however, this may not always fully describe how bZIP proteins interact with their target sites. Previously, we showed that the GCN4 basic region interacts with all 5 bp in half-site TTGCG (termed 5H-LR), and that 5H-LR comprises two 4-bp subsites, TTGC and TGCG, which individually are also target sites of the basic region. In this work, we explored how the basic region interacts with 5H-LR when the bZIP dimer localizes to full-sites. Using AMBER molecular modeling, we simulated GCN4 bZIP complexes with full-sites containing 5H-LR to investigate in silico the interface between the basic region and 5H-LR. We also performed in vitro investigation of bZIP–DNA interactions at a number of full-sites that contain 5H-LR vs. either subsite: we analyzed results from DNase I footprinting and electrophoretic mobility shift assay (EMSA) and from EMSA titrations to quantify binding affinities. Our computational and experimental results together support a highly dynamic DNA-binding model: when a bZIP dimer localizes to its target full-site, the basic region can alternately recognize either subsite as a distinct target at 5H-LR and translocate between the subsites, potentially by sliding and hopping. This model provides added insights into how α-helical DNA-binding domains of transcription factors can localize to their gene regulatory sequences in vivo. PMID:22856882

Characterization of pollen-expressed bZIP protein interactions and the role of ATbZIP18 in the male gametophyte.

PubMed

Gibalová, Antónia; Steinbachová, Lenka; Hafidh, Said; Bláhová, Veronika; Gadiou, Zuzana; Michailidis, Christos; Műller, Karel; Pleskot, Roman; Dupľáková, Nikoleta; Honys, David

2017-03-01

KEY MESSAGE : bZIP TF network in pollen. Transcriptional control of gene expression represents an important mechanism guiding organisms through developmental processes and providing plasticity towards environmental stimuli. Because of their sessile nature, plants require effective gene regulation for rapid response to variation in environmental and developmental conditions. Transcription factors (TFs) provide such control ensuring correct gene expression in spatial and temporal manner. Our work reports the interaction network of six bZIP TFs expressed in Arabidopsis thaliana pollen and highlights the potential functional role for AtbZIP18 in pollen. AtbZIP18 was shown to interact with three other pollen-expressed bZIP TFs-AtbZIP34, AtbZIP52, and AtbZIP61 in yeast two-hybrid assays. AtbZIP18 transcripts are highly expressed in pollen, and at the subcellular level, an AtbZIP18-GFP fusion protein was located in the nucleus and cytoplasm/ER. To address the role of AtbZIP18 in the male gametophyte, we performed phenotypic analysis of a T-DNA knockout allele, which showed slightly reduced transmission through the male gametophyte. Some of the phenotype defects in atbzip18 pollen, although observed at low penetrance, were similar to those seen at higher frequency in the T-DNA knockout of the interacting partner, AtbZIP34. To gain deeper insight into the regulatory role of AtbZIP18, we analysed atbzip18/- pollen microarray data. Our results point towards a potential repressive role for AtbZIP18 and its functional redundancy with AtbZIP34 in pollen.

Functional analysis RaZIP1 transporter of the ZIP family from the ectomycorrhizal Zn-accumulating Russula atropurpurea.

PubMed

Leonhardt, Tereza; Sácký, Jan; Kotrba, Pavel

2018-04-01

A search of R. atropurpurea transcriptome for sequences encoding the transporters of the Zrt-, Irt-like Protein (ZIP) family, which are in eukaryotes integral to Zn supply into cytoplasm, allowed the identification of RaZIP1 cDNA with a predicted product belonging to ZIP I subfamily; it was subjected to functional studies in mutant Saccharomyces cerevisiae strains. The expression of RaZIP1, but not RaZIP1 H208A or RaZIP1 H232A mutants lacking conserved-among-ZIPs transmembrane histidyls, complemented Zn uptake deficiency in zrt1Δzrt2Δ yeasts. RaZIP1 substantially increased cellular Zn uptake in this strain and added to Zn sensitivity in zrc1Δcot1Δ mutant. The Fe uptake deficiency in ftr1Δ strain was not rescued and Mn uptake was insufficient for toxicity in Mn-sensitive pmr1Δ yeasts. By contrast, RaZIP1 increased Cd sensitivity in yap1Δ strain and conferred Cd transport activity in yeasts, albeit with substantially lower efficiency compared to Zn transport. In metal uptake assays, the accumulation of Zn in zrt1Δzrt2Δ strain remained unaffected by Cd, Fe, and Mn present in 20-fold molar excess over Zn. Immunofluorescence microscopy detected functional hemagglutinin-tagged HA::RaZIP1 on the yeast cell protoplast periphery. Altogether, these data indicate that RaZIP1 is a high-affinity plasma membrane transporter specialized in Zn uptake, and improve the understanding of the cellular and molecular biology of Zn in R. atropurpurea that is known for its ability to accumulate remarkably high concentrations of Zn.

Search for Exoplanets around Northern Circumpolar Stars III. Long-Period Radial Velocity Variations in HD 18438 and HD 158996

NASA Astrophysics Data System (ADS)

Bang, Tae-Yang; Lee, Byeong-Cheol; Jeong, Gwang-hui; Han, Inwoo; Park, Myeong-Gu

2018-02-01

Detecting exoplanets around giants are useful in understanding the later-stage evolution of planetary systems. We observed the M giant HD 18438 and the K giant HD 158996 as part of a Search for Exoplanets around Northern circumpolar Stars (SENS) and obtained 38 and 24 spectra from 2010 to 2017 using the high-resolution Bohyunsan Observatory Echelle Spectrograph (BOES) at the 1.8m telescope of Bohyunsan Optical Astronomy Observatory in Korea. We obtained precise RV measurements from the spectra and found long-period radial velocity (RV) variations with period 719.0 days for HD 18438 and 820.2 days for HD 158996. We checked the chromospheric activities using Ca II H and H_{α} lines, HIPPARCOS photometry and line bisectors to identify the origin of the observed RV variations. In the case of HD 18438, we conclude that the observed RV variations with period 719.0 days are likely to be caused by the pulsations because the periods of HIPPARCOS photometric and H_{α} EW variations for HD 18438 are similar to that of RV variations in Lomb-Scargle periodogram, and there are no correlations between bisectors and RV measurements. In the case of HD 158996, on the other hand, we did not find any similarity in the respective periodograms nor any correlation between RV variations and line bisector variations. In addition, the probability that the real rotational period can be as longer than the RV period for HD 158996 is only about 4.3%. Thus we conclude that observed RV variations with a period of 820.2 days of HD 158996 are caused by a planetary companion, which has the minimum mass of 14.0 M_{Jup}, the semi-major axis of 2.1 AU, and eccentricity of 0.13 assuming the stellar mass of 1.8 M_{⊙}. HD 158996 is so far one of the brightest and largest stars to harbor exoplanet candidate.

A ZIP6-ZIP10 heteromer controls NCAM1 phosphorylation and integration into focal adhesion complexes during epithelial-to-mesenchymal transition.

PubMed

Brethour, Dylan; Mehrabian, Mohadeseh; Williams, Declan; Wang, Xinzhu; Ghodrati, Farinaz; Ehsani, Sepehr; Rubie, Elizabeth A; Woodgett, James R; Sevalle, Jean; Xi, Zhengrui; Rogaeva, Ekaterina; Schmitt-Ulms, Gerold

2017-01-18

The prion protein (PrP) evolved from the subbranch of ZIP metal ion transporters comprising ZIPs 5, 6 and 10, raising the prospect that the study of these ZIPs may reveal insights relevant for understanding the function of PrP. Building on data which suggested PrP and ZIP6 are critical during epithelial-to-mesenchymal transition (EMT), we investigated ZIP6 in an EMT paradigm using ZIP6 knockout cells, mass spectrometry and bioinformatic methods. Reminiscent of PrP, ZIP6 levels are five-fold upregulated during EMT and the protein forms a complex with NCAM1. ZIP6 also interacts with ZIP10 and the two ZIP transporters exhibit interdependency during their expression. ZIP6 contributes to the integration of NCAM1 in focal adhesion complexes but, unlike cells lacking PrP, ZIP6 deficiency does not abolish polysialylation of NCAM1. Instead, ZIP6 mediates phosphorylation of NCAM1 on a cluster of cytosolic acceptor sites. Substrate consensus motif features and in vitro phosphorylation data point toward GSK3 as the kinase responsible, and interface mapping experiments identified histidine-rich cytoplasmic loops within the ZIP6/ZIP10 heteromer as a novel scaffold for GSK3 binding. Our data suggests that PrP and ZIP6 inherited the ability to interact with NCAM1 from their common ZIP ancestors but have since diverged to control distinct posttranslational modifications of NCAM1.

Studies of FCAPT uvby Photometry with Period04: The mCP Stars HD 5797, HD 36792, HD 27309, HD 47913, HD 74521, HD 120198, HD 171263, and HD 215441

NASA Astrophysics Data System (ADS)

Dukes, Robert J., Jr.; Adelman, Saul J.

2018-04-01

We present differential Strömgren uvby Four College Automated Photometric Telescope (FCAPT) observations of eight magnetic chemically peculiar stars: HD 5797, HD 26792, HD 27309, HD 49713, HD 74521, HD 120198, HD 171263, and HD 215441. Our data sets are larger than those of most mCP stars in the literature. These are the first FCAPT observations of HD 5797, HD 26792, HD 49713, and HD 171263. Those for the other four stars substantially extend published FCAPT data sets. The FCAPT has observed some stars for a longer time range and with greater accuracy than other optical region telescopes. We determine very accurate periods and u, v, b, and y amplitudes, as well as if there are any long-term periods. Further, we compare our results with those of magnetic field measurements, when they exist, to help interpret the light curves. For each star, we used the Period04 computer program to analyze the uvby light curves. This program provides errors for the derived quantities. Our derived periods of 68.0457 ± 0.0200 days for HD 5797, 3.80205 ± 0.00015 days for HD 26792, 1.5688908 ± 0.0000046 days for HD 27309, 2.135361 ± 0.000031 days for HD 49713, 7.05053 ± 0.00024 for days HD 74521, 1.3857690 ± 0.0000058 days for HD 120198, 3.99744 ± 0.00015 days for HD 171263, and 9.487792 ± 0.000049 days for HD 215441 are refinements of the last determinations in the literature. We also found a low-frequency term for HD 49713 in all four filters.

OsLOL1, a C2C2-type zinc finger protein, interacts with OsbZIP58 to promote seed germination through the modulation of gibberellin biosynthesis in Oryza sativa.

PubMed

Wu, Jiahe; Zhu, Chuanfeng; Pang, Jinhuan; Zhang, Xiangrong; Yang, Chunlin; Xia, Guixian; Tian, Yingchuan; He, Chaozu

2014-12-01

Seed germination is a key developmental process in the plant life cycle that is influenced by various environmental cues and phytohormones through gene expression and a series of metabolism pathways. In the present study, we investigated a C2C2-type finger protein, OsLOL1, which promotes gibberellin (GA) biosynthesis and affects seed germination in Oryza sativa (rice). We used OsLOL1 antisense and sense transgenic lines to explore OsLOL1 functions. Seed germination timing in antisense plants was restored to wild type when exogenous GA3 was applied. The reduced expression of the GA biosynthesis gene OsKO2 and the accumulation of ent-kaurene were observed during germination in antisense plants. Based on yeast two-hybrid and firefly luciferase complementation analyses, OsLOL1 interacted with the basic leucine zipper protein OsbZIP58. The results from electrophoretic mobility shift and dual-luciferase reporter assays showed that OsbZIP58 binds the G-box cis-element of the OsKO2 promoter and activates LUC reporter gene expression, and that interaction between OsLOL1 and OsbZIP58 activates OsKO2 gene expression. In addition, OsLOL1 decreased SOD1 gene expression and accelerated programmed cell death (PCD) in the aleurone layer of rice grains. These findings demonstrate that the interaction between OsLOL1 and OsbZIP58 influences GA biosynthesis through the activation of OsKO2 via OsbZIP58, thereby stimulating aleurone PCD and seed germination. © 2014 The Authors The Plant Journal © 2014 John Wiley & Sons Ltd.

HapZipper: sharing HapMap populations just got easier.

PubMed

Chanda, Pritam; Elhaik, Eran; Bader, Joel S

2012-11-01

The rapidly growing amount of genomic sequence data being generated and made publicly available necessitate the development of new data storage and archiving methods. The vast amount of data being shared and manipulated also create new challenges for network resources. Thus, developing advanced data compression techniques is becoming an integral part of data production and analysis. The HapMap project is one of the largest public resources of human single-nucleotide polymorphisms (SNPs), characterizing over 3 million SNPs genotyped in over 1000 individuals. The standard format and biological properties of HapMap data suggest that a dedicated genetic compression method can outperform generic compression tools. We propose a compression methodology for genetic data by introducing HapZipper, a lossless compression tool tailored to compress HapMap data beyond benchmarks defined by generic tools such as gzip, bzip2 and lzma. We demonstrate the usefulness of HapZipper by compressing HapMap 3 populations to <5% of their original sizes. HapZipper is freely downloadable from https://bitbucket.org/pchanda/hapzipper/downloads/HapZipper.tar.bz2.

The homeodomain-leucine zipper (HD-Zip) class I transcription factors ATHB7 and ATHB12 modulate abscisic acid signalling by regulating protein phosphatase 2C and abscisic acid receptor gene activities.

PubMed

Valdés, Ana Elisa; Overnäs, Elin; Johansson, Henrik; Rada-Iglesias, Alvaro; Engström, Peter

2012-11-01

Plants perceiving drought activate multiple responses to improve survival, including large-scale alterations in gene expression. This article reports on the roles in the drought response of two Arabidopsis thaliana homeodomain-leucine zipper class I genes; ATHB7 and ATHB12, both strongly induced by water-deficit and abscisic acid (ABA). ABA-mediated transcriptional regulation of both genes is shown to depend on the activity of protein phosphatases type 2C (PP2C). ATHB7 and ATHB12 are, thus, targets of the ABA signalling mechanism defined by the PP2Cs and the PYR/PYL family of ABA receptors, with which the PP2C proteins interact. Our results from chromatin immunoprecipitation and gene expression analyses demonstrate that ATHB7 and ATHB12 act as positive transcriptional regulators of PP2C genes, and thereby as negative regulators of abscisic acid signalling. In support of this notion, our results also show that ATHB7 and ATHB12 act to repress the transcription of genes encoding the ABA receptors PYL5 and PYL8 in response to an ABA stimulus. In summary, we demonstrate that ATHB7 and ATHB12 have essential functions in the primary response to drought, as mediators of a negative feedback effect on ABA signalling in the plant response to water deficit.

MicroRNA166 Modulates Cadmium Tolerance and Accumulation in Rice.

PubMed

Ding, Yanfei; Gong, Shaohua; Wang, Yi; Wang, Feijuan; Bao, Hexigeduleng; Sun, Junwei; Cai, Chong; Yi, Keke; Chen, Zhixiang; Zhu, Cheng

2018-06-20

MicroRNAs (miRNAs) are 20- to 24-nucleotide small non-coding RNAs that regulate gene expression in eukaryotic organisms. Several plant miRNAs, such as miR166, have vital roles in plant growth, development and responses to environmental stresses. One such environmental stress encountered by crop plants is exposure to cadmium (Cd), an element highly toxic to most organisms, including humans and plants. In this study, we analyzed the role of miR166 in Cd accumulation and tolerance in rice (Oryza sativa). The expression levels of miR166 in both root and leaf tissues were significantly higher in the reproductive stage than in the seedling stage in rice. The expression of miR166 in the roots of rice seedlings was reduced after Cd treatment. Overexpression of miR166 in rice improved Cd tolerance, a result associated with the reduction of Cd-induced oxidative stress in transgenic rice plants. Furthermore, overexpression of miR166 reduced both Cd translocation from roots to shoots and Cd accumulation in the grains. miR166 targets genes encoding the class-III homeodomain-leucine zipper (HD-Zip) family proteins in plants. In rice, HOMEODOMAIN CONTAINING PROTEIN 4 (OsHB4) gene (Os03g43930), which encodes an HD-Zip protein, was up-regulated by Cd treatment but down-regulated by overexpression of miR166 in transgenic rice plants. Overexpression of OsHB4 increased Cd sensitivity and Cd accumulation in the leaves and grains of transgenic rice plants. By contrast, silencing OsHB4 by RNA interference enhanced Cd tolerance in transgenic rice plants. These results indicate a critical role for miR166 in Cd accumulation and tolerance through regulation of its target gene, OsHB4, in rice. {copyright, serif} 2018 American Society of Plant Biologists. All rights reserved.

Functional analysis of rice HOMEOBOX4 (Oshox4) gene reveals a negative function in gibberellin responses.

PubMed

Dai, Mingqiu; Hu, Yongfeng; Ma, Qian; Zhao, Yu; Zhou, Dao-Xiu

2008-02-01

The homeodomain-leucine zipper (HD-Zip) putative transcription factor genes are divided into 4 families. In this work, we studied the function of a rice HD-Zip I gene, H OME O BO X4 (Oshox4). Oshox4 transcripts were detected in leaf and floral organ primordia but excluded from the shoot apical meristem and the protein was nuclear localized. Over-expression of Oshox4 in rice induced a semi-dwarf phenotype that could not be complemented by applied GA3. The over-expression plants accumulated elevated levels of bioactive GA, while the GA catabolic gene GA2ox3 was upregulated in the transgenic plants. In addition, over-expression of Oshox4 blocked GA-dependent alpha-amylase production. However, down-regulation of Oshox4 in RNAi transgenic plants induced no phenotypic alteration. Interestingly, the expression of YAB1 that is involved in the negative feedback regulation of the GA biosynthesis was upregulated in the Oshox4 over-expressing plants. One-hybrid assays showed that Oshox4 could interact with YAB1 promoter in yeast. In addition, Oshox4 expression was upregulated by GA. These data together suggest that Oshox4 may be involved in the negative regulation of GA signalling and may play a role to fine tune GA responses in rice.

The HTLV-1 basic leucine zipper factor (HBZ) attenuates repair of double-stranded DNA breaks via non-homologous end joining (NHEJ).

PubMed

Rushing, A W; Hoang, K; Polakowski, N; Lemasson, I

2018-05-16

Adult T-cell leukemia (ATL) is a fatal malignancy of CD4 + T-cells infected with human T-cell leukemia virus type I (HTLV-1). ATL cells often exhibit random gross chromosomal rearrangements that are associated with the induction and improper repair of double-stranded DNA breaks (DSBs). The viral oncoprotein Tax has been reported to impair DSB repair, but is not shown to be consistently expressed throughout all phases of infection. The viral oncoprotein HTLV-1 basic leucine zipper factor (HBZ) is consistently expressed prior to and throughout disease progression, but it is unclear whether it also influences DSB repair. We report that HBZ attenuates DSB repair by non-homologous end joining (NHEJ), in a manner dependent upon the basic leucine zipper (bZIP) domain. HBZ was found to interact with two vital members of the NHEJ core machinery, Ku70 and Ku80, and to be recruited to DSBs in a bZIP-dependent manner in vitro We observed that HBZ expression also resulted in a bZIP-dependent delay in DNA-PK activation following treatment with etoposide. Though Tax is reported to interact with Ku70, we did not find Tax expression to interfere with HBZ:Ku complex formation. However, as Tax was reported to saturate NHEJ, we found this effect masked the attenuation of NHEJ by HBZ. Overall, these data suggest that DSB repair mechanisms are impaired not only by Tax, but also by HBZ, and show that HBZ expression may significantly contribute to the accumulation of chromosomal abnormalities during HTLV-1 mediated oncogenesis. IMPORTANCE Human T-cell leukemia virus type 1 (HTLV-1) infects 15-20 million people worldwide. Approximately 90% of infected individuals are asymptomatic and may remain undiagnosed, increasing the risk that they will unknowingly transmit the virus. About 5% of the HTLV-1 positive population to develop Adult T-cell Leukemia (ATL), a fatal disease that is not highly responsive to treatment. Though ATL development remains poorly understood, two viral proteins, Tax and

The role of ZIP transporters and group F bZIP transcription factors in the Zn-deficiency response of wheat (Triticum aestivum).

PubMed

Evens, Nicholas P; Buchner, Peter; Williams, Lorraine E; Hawkesford, Malcolm J

2017-10-01

Understanding the molecular basis of zinc (Zn) uptake and transport in staple cereal crops is critical for improving both Zn content and tolerance to low-Zn soils. This study demonstrates the importance of group F bZIP transcription factors and ZIP transporters in responses to Zn deficiency in wheat (Triticum aestivum). Seven group F TabZIP genes and 14 ZIPs with homeologs were identified in hexaploid wheat. Promoter analysis revealed the presence of Zn-deficiency-response elements (ZDREs) in a number of the ZIPs. Functional complementation of the zrt1/zrt2 yeast mutant by TaZIP3, -6, -7, -9 and -13 supported an ability to transport Zn. Group F TabZIPs contain the group-defining cysteine-histidine-rich motifs, which are the predicted binding site of Zn 2+ in the Zn-deficiency response. Conservation of these motifs varied between the TabZIPs suggesting that individual TabZIPs may have specific roles in the wheat Zn-homeostatic network. Increased expression in response to low Zn levels was observed for several of the wheat ZIPs and bZIPs; this varied temporally and spatially suggesting specific functions in the response mechanism. The ability of the group F TabZIPs to bind to specific ZDREs in the promoters of TaZIPs indicates a conserved mechanism in monocots and dicots in responding to Zn deficiency. In support of this, TabZIPF1-7DL and TabZIPF4-7AL afforded a strong level of rescue to the Arabidopsis hypersensitive bzip19 bzip23 double mutant under Zn deficiency. These results provide a greater understanding of Zn-homeostatic mechanisms in wheat, demonstrating an expanded repertoire of group F bZIP transcription factors, adding to the complexity of Zn homeostasis. © 2017 The Authors The Plant Journal published by John Wiley & Sons Ltd and Society for Experimental Biology.

A petunia homeodomain-leucine zipper protein, PhHD-Zip, plays an important role in flower senescence

USDA-ARS?s Scientific Manuscript database

Flower senescence is mediated in part by changes of plant hormones, such as ethylene, cytokinin and abscisic acid (ABA). Ethylene is known to control flower senescence in many species, especially ethylene sensitive flowers, like petunia, carnation and rose. During flower senescence in petunia and ot...

Capsicum annuum homeobox 1 (CaHB1) is a nuclear factor that has roles in plant development, salt tolerance, and pathogen defense

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

Oh, Sang-Keun; Yoon, Joonseon; Choi, Gyung Ja

Highlights: •The CaHB1 is a nuclear factor, belonging to HD-Zip proteins. •SA and ET, as signal molecules, modulate CaHB1-mediated responses. •Overexpression of CaHB1 in tomato resulted in a thicker cell wall. •CaHB1-transgenic tomato confers resistance to Phytophthora infestans. •CaHB1 enhanced tolerance to saline stress in tomato. -- Abstract: Homeodomain-leucine zipper (HD-Zip) family proteins are unique to plants, but little is known about their role in defense responses. CaHB1 is a nuclear factor in peppers, belonging to subfamily II of HD-Zip proteins. Here, we determined the role of CaHB1 in the defense response. CaHB1 expression was induced when pepper plants weremore » challenged with Phytophthora capsici, a plant pathogen to which peppers are susceptible, or environmental stresses such as drought and salt stimuli. CaHB1 was also highly expressed in pepper leaves following application of SA, whereas ethephon and MeJA had a moderate effect. To further investigate the function of CaHB1 in plants, we performed gain-of-function study by overexpression of CaHB1 in tomato. CaHB1-transgenic tomatoes showed significant growth enhancement including increased leaf thickness and enlarged cell size (1.8-fold larger than control plants). Microscopic analysis revealed that leaves from CaHB1-transgenic plants had thicker cell walls and cuticle layers than those from controls. Moreover, CaHB1-transgenic plants displayed enhanced resistance against Phytophthora infestans and increased tolerance to salt stress. Additionally, RT-PCR analysis of CaHB1-transgenic tomatoes revealed constitutive up-regulation of multiple genes involved in plant defense and osmotic stress. Therefore, our findings suggest roles for CaHB1 in development, salt stress, and pathogen defense.« less

Applicability of Zipper Merge Versus Early Merge in Kentucky Work Zones

DOT National Transportation Integrated Search

2017-12-24

In an effort to improve work zone safety and streamline traffic flows, a number of state transportation agencies (STAs) have experimented with the zipper merge. The zipper merge differs from a conventional, or early, merge in that vehicles do not mer...

"Hit-and-Run" transcription: de novo transcription initiated by a transient bZIP1 "hit" persists after the "run".

PubMed

Doidy, Joan; Li, Ying; Neymotin, Benjamin; Edwards, Molly B; Varala, Kranthi; Gresham, David; Coruzzi, Gloria M

2016-02-03

Dynamic transcriptional regulation is critical for an organism's response to environmental signals and yet remains elusive to capture. Such transcriptional regulation is mediated by master transcription factors (TF) that control large gene regulatory networks. Recently, we described a dynamic mode of TF regulation named "hit-and-run". This model proposes that master TF can interact transiently with a set of targets, but the transcription of these transient targets continues after the TF dissociation from the target promoter. However, experimental evidence validating active transcription of the transient TF-targets is still lacking. Here, we show that active transcription continues after transient TF-target interactions by tracking de novo synthesis of RNAs made in response to TF nuclear import. To do this, we introduced an affinity-labeled 4-thiouracil (4tU) nucleobase to specifically isolate newly synthesized transcripts following conditional TF nuclear import. Thus, we extended the TARGET system (Transient Assay Reporting Genome-wide Effects of Transcription factors) to include 4tU-labeling and named this new technology TARGET-tU. Our proof-of-principle example is the master TF Basic Leucine Zipper 1 (bZIP1), a central integrator of metabolic signaling in plants. Using TARGET-tU, we captured newly synthesized mRNAs made in response to bZIP1 nuclear import at a time when bZIP1 is no longer detectably bound to its target. Thus, the analysis of de novo transcripomics demonstrates that bZIP1 may act as a catalyst TF to initiate a transcriptional complex ("hit"), after which active transcription by RNA polymerase continues without the TF being bound to the gene promoter ("run"). Our findings provide experimental proof for active transcription of transient TF-targets supporting a "hit-and-run" mode of action. This dynamic regulatory model allows a master TF to catalytically propagate rapid and broad transcriptional responses to changes in environment. Thus, the

The bZIP repressor proteins, c-Jun dimerization protein 2 and activating transcription factor 3, recruit multiple HDAC members to the ATF3 promoter.

PubMed

Darlyuk-Saadon, Ilona; Weidenfeld-Baranboim, Keren; Yokoyama, Kazunari K; Hai, Tsonwin; Aronheim, Ami

2012-01-01

JDP2, is a basic leucine zipper (bZIP) protein displaying a high degree of homology with the stress inducible transcription factor, ATF3. Both proteins bind to cAMP and TPA response elements and repress transcription by multiple mechanisms. Histone deacetylases (HDACs) play a key role in gene inactivation by deacetylating lysine residues on histones. Here we describe the association of JDP2 and ATF3 with HDACs 1, 2-6 and 10. Association of HDAC3 and HDAC6 with JDP2 and ATF3 occurs via direct protein-protein interactions. Only part of the N-terminal bZIP motif of JDP2 and ATF3 basic domain is necessary and sufficient for the interaction with HDACs in a manner that is independent of coiled-coil dimerization. Class I HDACs associate with the bZIP repressors via the DAC conserved domain whereas the Class IIb HDAC6 associates through its C-terminal unique binder of ubiquitin Zn finger domain. Both JDP2 and ATF3 are known to bind and repress the ATF3 promoter. MEF cells treated with histone deacetylase inhibitor, trichostatin A (TSA) display enhanced ATF3 transcription. ATF3 enhanced transcription is significantly reduced in MEF cells lacking both ATF3 and JDP2. Collectively, we propose that the recruitment of multiple HDAC members to JDP2 and ATF3 is part of their transcription repression mechanism. Copyright © 2012 Elsevier B.V. All rights reserved.

Axon tension regulates fasciculation/defasciculation through the control of axon shaft zippering

PubMed Central

Šmít, Daniel; Fouquet, Coralie; Pincet, Frédéric; Zapotocky, Martin; Trembleau, Alain

2017-01-01

While axon fasciculation plays a key role in the development of neural networks, very little is known about its dynamics and the underlying biophysical mechanisms. In a model system composed of neurons grown ex vivo from explants of embryonic mouse olfactory epithelia, we observed that axons dynamically interact with each other through their shafts, leading to zippering and unzippering behavior that regulates their fasciculation. Taking advantage of this new preparation suitable for studying such interactions, we carried out a detailed biophysical analysis of zippering, occurring either spontaneously or induced by micromanipulations and pharmacological treatments. We show that zippering arises from the competition of axon-axon adhesion and mechanical tension in the axons, and provide the first quantification of the force of axon-axon adhesion. Furthermore, we introduce a biophysical model of the zippering dynamics, and we quantitatively relate the individual zipper properties to global characteristics of the developing axon network. Our study uncovers a new role of mechanical tension in neural development: the regulation of axon fasciculation. DOI: http://dx.doi.org/10.7554/eLife.19907.001 PMID:28422009

Tissue-Specific Induction of Mouse ZIP8 and ZIP14 Divalent Cation/Bicarbonate Symporters by, and Cytokine Response to, Inflammatory Signals

PubMed Central

Gálvez-Peralta, Marina; Wang, Zhifang; Bao, Shengying; Knoell, Daren L; Nebert, Daniel W

2014-01-01

Mouse Slc39a8 and Slc39a14 genes encode ZIP8 and ZIP14, respectively, which are ubiquitous divalent cation/(HCO3−)2 symporters responsible for uptake of Zn2+, Fe2+ and Mn2+ into cells. Cd2+ and other toxic nonessential metals can displace essential cations, thereby entering vertebrate cells. Whereas Slc39a8 encodes a single protein, Slc39a14 has two exons 4 which, via alternative splicing, give rise to ZIP14A and ZIP14B; why differences exist in cell-type-specific expression of ZIP14A and ZIP14B remains unknown. Inflammatory stimuli have been associated with ZIP8 and ZIP14 up-regulation, but a systematic study of many tissues simultaneously in a laboratory animal following inflammatory cytokine exposure has not yet been reported. Herein we show that C57BL/6J male mice—treated intraperitoneally with lipopolysaccharide (LPS), or the proinflammatory cytokines tumor necrosis factor (TNF) or interleukin-6 (IL6)—exhibited quantatively very different, highly tissue-specific, and markedly time-dependent up- and down-regulation of ZIP8, ZIP14A and ZIP14B mRNA levels in twelve tissues. Magnitude of the inflammatory response was confirmed by measuring the proinflammatory cytokine TNF, IL6 and interleukin-1β (IL1B) mRNA levels in the same tissues of these animals. Our data suggest that most if not all tissues use ZIP8, ZIP14A and/or ZIP14B) for Zn2+ uptake, some tissues under basal conditions and others moreso when inflammatory stressors are present; collectively, this might lead to substantial alterations in plasma Zn2+ levels, due to Zn2+ redistribution not just in liver, but across many vital organs. In the context of cadmium-mediated toxicity, our data suggest that tissues other than liver, kidney and lung should also be considered. PMID:24728862

A Novel Wheat C-bZIP Gene, TabZIP14-B, Participates in Salt and Freezing Tolerance in Transgenic Plants

PubMed Central

Zhang, Lina; Zhang, Lichao; Xia, Chuan; Gao, Lifeng; Hao, Chenyang; Zhao, Guangyao; Jia, Jizeng; Kong, Xiuying

2017-01-01

The group C-bZIP transcription factors (TFs) are involved in diverse biological processes, such as the regulation of seed storage protein (SSP) production and the responses to pathogen challenge and abiotic stress. However, our knowledge of the abiotic functions of group C-bZIP genes in wheat remains limited. Here, we present the function of a novel TabZIP14-B gene in wheat. This gene belongs to the group C-bZIP TFs and contains six exons and five introns; three haplotypes were identified among accessions of tetraploid and hexaploid wheat. A subcellular localization analysis indicated that TabZIP14-B was targeted to the nucleus of tobacco epidermal cells. A transactivation assay demonstrated that TabZIP14-B showed transcriptional activation ability and was capable of binding the abscisic acid (ABA) responsive element (ABRE) in yeast. RT-qPCR revealed that TabZIP14-B was expressed in the roots, stems, leaves, and young spikes and was up-regulated by exogenous ABA, salt, low-temperature, and polyethylene glycol (PEG) stress treatments. Furthermore, Arabidopsis plants overexpressing TabZIP14-B exhibited enhanced tolerance to salt, freezing stresses and ABA sensitivity. Overexpression of TabZIP14-B resulted in increased expression of the AtRD29A, AtCOR47, AtRD20, AtGSTF6, and AtRAB18 genes and changes in several physiological characteristics. These results suggest that TabZIP14-B could function as a positive regulator in mediating the abiotic stress response. PMID:28536588

Characterization of leucine zipper complexes by electrospray ionization mass spectrometry.

PubMed Central

Wendt, H.; Dürr, E.; Thomas, R. M.; Przybylski, M.; Bosshard, H. R.

1995-01-01

The development of "soft" ionization methods has enabled the mass spectrometric analysis of higher-order structural features of proteins. We have applied electrospray ionization mass spectrometry (ESI-MS) to the analysis of the number and composition of polypeptide chains in homomeric and heteromeric leucine zippers. In comparison with other methods that have been used to analyze leucine zippers, such as analytical ultracentrifugation, gel chromatography, or electrophoretic band shift assays, ESI-MS is very fast and highly sensitive and provides a straightforward way to distinguish between homomeric and heteromeric coiled-coil structures. ESI-MS analyses were carried out on the parallel dimeric leucine zipper domain GCN4-p1 of the yeast transcription factor GCN4 and on three synthetic peptides with the sequences Ac-EYEALEKKLAAX1EAKX2QALEKKLEALEHG-amide: peptide LZ (X1, X2 = Leu), peptide LZ(12A) (X1 = Ala, X2 = Leu), and peptide LZ(16N) (X1 = Leu, X2 = Asn). Equilibrium ultracentrifugation analysis showed that LZ forms a trimeric coiled coil and this could be confirmed unequivocally by ESI-MS as could the dimeric nature of GCN4-p1. The formation of heteromeric two- and three-stranded leucine zippers composed of chains from LZ and LZ(12A), or from GCN4-p1 and LZ, was demonstrated by ESI-MS and confirmed by fluorescence quenching experiments on fluorescein-labeled peptides. The results illustrate the adaptability and flexibility of the leucine zipper motif, properties that could be useful to the design of specific protein assemblies by way of coiled-coil domains. PMID:8520482

Soybean extracts increase cell surface ZIP4 abundance and cellular zinc levels: a potential novel strategy to enhance zinc absorption by ZIP4 targeting.

PubMed

Hashimoto, Ayako; Ohkura, Katsuma; Takahashi, Masakazu; Kizu, Kumiko; Narita, Hiroshi; Enomoto, Shuichi; Miyamae, Yusaku; Masuda, Seiji; Nagao, Masaya; Irie, Kazuhiro; Ohigashi, Hajime; Andrews, Glen K; Kambe, Taiho

2015-12-01

Dietary zinc deficiency puts human health at risk, so we explored strategies for enhancing zinc absorption. In the small intestine, the zinc transporter ZIP4 functions as an essential component of zinc absorption. Overexpression of ZIP4 protein increases zinc uptake and thereby cellular zinc levels, suggesting that food components with the ability to increase ZIP4 could potentially enhance zinc absorption via the intestine. In the present study, we used mouse Hepa cells, which regulate mouse Zip4 (mZip4) in a manner indistinguishable from that in intestinal enterocytes, to screen for suitable food components that can increase the abundance of ZIP4. Using this ZIP4-targeting strategy, two such soybean extracts were identified that were specifically able to decrease mZip4 endocytosis in response to zinc. These soybean extracts also effectively increased the abundance of apically localized mZip4 in transfected polarized Caco2 and Madin-Darby canine kidney cells and, moreover, two apically localized mZip4 acrodermatitis enteropathica mutants. Soybean components were purified from one extract and soyasaponin Bb was identified as an active component that increased both mZip4 protein abundance and zinc levels in Hepa cells. Finally, we confirmed that soyasaponin Bb is capable of enhancing cell surface endogenous human ZIP4 in human cells. Our results suggest that ZIP4 targeting may represent a new strategy to improve zinc absorption in humans. © 2015 Authors; published by Portland Press Limited.

Thermodynamic analysis of the heterodimerization of leucine zippers of Jun and Fos transcription factors

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

Seldeen, Kenneth L.; McDonald, Caleb B.; Deegan, Brian J.

2008-10-31

Jun and Fos are components of the AP1 family of transcription factors and bind to the promoters of a diverse multitude of genes involved in critical cellular responses such as cell growth and proliferation, cell cycle regulation, embryonic development and cancer. Here, using the powerful technique of isothermal titration calorimetry, we characterize the thermodynamics of heterodimerization of leucine zippers of Jun and Fos. Our data suggest that the heterodimerization of leucine zippers is driven by enthalpic forces with unfavorable entropy change at physiological temperatures. Furthermore, the basic regions appear to modulate the heterodimerization of leucine zippers and may undergo atmore » least partial folding upon heterodimerization. Large negative heat capacity changes accompanying the heterodimerization of leucine zippers are consistent with the view that leucine zippers do not retain {alpha}-helical conformations in isolation and that the formation of the native coiled-coil {alpha}-helical dimer is attained through a coupled folding-dimerization mechanism.« less

The HARPS search for southern extra-solar planets. III. Three Saturn-mass planets around HD 93083, HD 101930 and HD 102117

NASA Astrophysics Data System (ADS)

Lovis, C.; Mayor, M.; Bouchy, F.; Pepe, F.; Queloz, D.; Santos, N. C.; Udry, S.; Benz, W.; Bertaux, J.-L.; Mordasini, C.; Sivan, J.-P.

2005-07-01

We report on the detection of three Saturn-mass planets discovered with the HARPS instrument. HD 93083 shows radial-velocity (RV) variations best explained by the presence of a companion of 0.37 MJup orbiting in 143.6 days. HD 101930 b has an orbital period of 70.5 days and a minimum mass of 0.30 MJup. For HD 102117, we present the independent detection of a companion with m2 sin{i} = 0.14 MJup and orbital period P = 20.7 days. This planet was recently detected by Tinney et al. (ApJ, submitted). Activity and bisector indicators exclude any significant RV perturbations of stellar origin, reinforcing the planetary interpretation of the RV variations. The radial-velocity residuals around the Keplerian fits are 2.0, 1.8 and 0.9 m s-1 respectively, showing the unprecedented RV accuracy achieved with HARPS. A sample of stable stars observed with HARPS is also presented to illustrate the long-term precision of the instrument. All three stars are metal-rich, confirming the now well-established relation between planet occurrence and metallicity. The new planets are all in the Saturn-mass range, orbiting at moderate distance from their parent star, thereby occupying an area of the parameter space which seems difficult to populate according to planet formation theories. A systematic exploration of these regions will provide new constraints on formation scenarios in the near future.

Nuclear Import of the Parsley bZIP Transcription Factor CPRF2 Is Regulated by Phytochrome Photoreceptors

PubMed Central

Kircher, Stefan; Wellmer, Frank; Nick, Peter; Rügner, Alexander; Schäfer, Eberhard; Harter, Klaus

1999-01-01

In plants, light perception by photoreceptors leads to differential expression of an enormous number of genes. An important step for differential gene expression is the regulation of transcription factor activities. To understand these processes in light signal transduction we analyzed the three well-known members of the common plant regulatory factor (CPRF) family from parsley (Petroselinum crispum). Here, we demonstrate that these CPRFs, which belong to the basic- region leucine-zipper (bZIP) domain-containing transcription factors, are differentially distributed within parsley cells, indicating different regulatory functions within the regulatory networks of the plant cell. In particular, we show by cell fractionation and immunolocalization approaches that CPRF2 is transported from the cytosol into the nucleus upon irradiation due to action of phytochrome photoreceptors. Two NH2-terminal domains responsible for cytoplasmic localization of CPRF2 in the dark were characterized by deletion analysis using a set of CPRF2-green fluorescent protein (GFP) gene fusion constructs transiently expressed in parsley protoplasts. We suggest that light-induced nuclear import of CPRF2 is an essential step in phytochrome signal transduction. PMID:9922448

The ZIP family zinc transporters support the virulence of Cryptococcus neoformans

PubMed Central

Do, Eunsoo; Hu, Guanggan; Caza, Mélissa; Kronstad, James W.; Jung, Won Hee

2016-01-01

Zinc is an essential element in living organisms and a cofactor for various metalloproteins. To disseminate and survive, a pathogenic microbe must obtain zinc from the host, which is an environment with extremely limited zinc availability. In this study, we investigated the roles of the ZIP family zinc transporters Zip1 and Zip2 in the human pathogenic fungus Cryptococcus neoformans. Zip1 and Zip2 are homologous to Zrt1 and Zrt2 of the model fungus, Saccharomyces cerevisiae, respectively. We found that the expression of ZIP1 was regulated by the zinc concentration in the environment. Furthermore, the mutant lacking ZIP1 displayed a severe growth defect under zinc-limited conditions, while the mutant lacking ZIP2 displayed normal growth. Inductively coupled plasma–atomic emission spectroscopy analysis showed that the absence of Zip1 expression significantly reduced total cellular zinc levels relative to that in the wild type, while overexpression of Zip1 was associated with increased cellular zinc levels. These findings suggested that Zip1 plays roles in zinc uptake in C. neoformans. We also constructed a Zip1-FLAG fusion protein and found, by immunofluorescence, not only that the protein was localized to the periphery implying it is a membrane transporter, but also that the protein was N-glycosylated. Furthermore, the mutant lacking ZIP1 showed attenuated virulence in a murine inhalation model of cryptococcosis and reduced survival within murine macrophages. Overall, our data suggest that Zip1 plays essential roles in zinc transport and the virulence of C. neoformans. PMID:27118799

The homologous HD-Zip I transcription factors HaHB1 and AtHB13 confer cold tolerance via the induction of pathogenesis-related and glucanase proteins.

PubMed

Cabello, Julieta V; Arce, Agustín L; Chan, Raquel L

2012-01-01

Plants deal with cold temperatures via different signal transduction pathways. The HD-Zip I homologous transcription factors HaHB1 from sunflower and AtHB13 from Arabidopsis were identified as playing a key role in such cold response. The expression patterns of both genes were analyzed indicating an up-regulation by low temperatures. When these genes were constitutively expressed in Arabidopsis, the transgenic plants showed similar phenotypes including cell membrane stabilization under freezing treatments and cold tolerance. An exploratory transcriptomic analysis of HaHB1 transgenic plants indicated that several transcripts encoding glucanases and chitinases were induced. Moreover, under freezing conditions some proteins accumulated in HaHB1 plants apoplasts and these extracts exerted antifreeze activity in vitro. Three genes encoding two glucanases and a chitinase were overexpressed in Arabidopsis and these plants were able to tolerate freezing temperatures. All the obtained transgenic plants exhibited cell membrane stabilization after a short freezing treatment. Finally, HaHB1 and AtHB13 were used to transiently transform sunflower and soybean leading to the up-regulation of HaHB1/AtHB13-target homologues thus indicating the conservation of cold response pathways. We propose that HaHB1 and AtHB13 are involved in plant cold tolerance via the induction of proteins able to stabilize cell membranes and inhibit ice growth. © 2011 The Authors. The Plant Journal © 2011 Blackwell Publishing Ltd.

An engineered allosteric switch in leucine-zipper oligomerization.

PubMed

Gonzalez, L; Plecs, J J; Alber, T

1996-06-01

Controversy remains about the role of core side-chain packing in specifying protein structure. To investigate the influence of core packing on the oligomeric structure of a coiled coil, we engineered a GCN4 leucine zipper mutant that switches from two to three strands upon binding the hydrophobic ligands cyclohexane and benzene. In solution these ligands increased the apparent thermal stability and the oligomerization order of the mutant leucine zipper. The crystal structure of the peptide-benzene complex shows a single benzene molecule bound at the engineered site in the core of the trimer. These results indicate that coiled coils are well-suited to function as molecular switches and emphasize that core packing is an important determinant of oligomerization specificity.

Identification and application of self-binding zipper-like sequences in SARS-CoV spike protein.

PubMed

Zhang, Si Min; Liao, Ying; Neo, Tuan Ling; Lu, Yanning; Liu, Ding Xiang; Vahlne, Anders; Tam, James P

2018-05-22

Self-binding peptides containing zipper-like sequences, such as the Leu/Ile zipper sequence within the coiled coil regions of proteins and the cross-β spine steric zippers within the amyloid-like fibrils, could bind to the protein-of-origin through homophilic sequence-specific zipper motifs. These self-binding sequences represent opportunities for the development of biochemical tools and/or therapeutics. Here, we report on the identification of a putative self-binding β-zipper-forming peptide within the severe acute respiratory syndrome-associated coronavirus spike (S) protein and its application in viral detection. Peptide array scanning of overlapping peptides covering the entire length of S protein identified 34 putative self-binding peptides of six clusters, five of which contained octapeptide core consensus sequences. The Cluster I consensus octapeptide sequence GINITNFR was predicted by the Eisenberg's 3D profile method to have high amyloid-like fibrillation potential through steric β-zipper formation. Peptide C6 containing the Cluster I consensus sequence was shown to oligomerize and form amyloid-like fibrils. Taking advantage of this, C6 was further applied to detect the S protein expression in vitro by fluorescence staining. Meanwhile, the coiled-coil-forming Leu/Ile heptad repeat sequences within the S protein were under-represented during peptide array scanning, in agreement with that long peptide lengths were required to attain high helix-mediated interaction avidity. The data suggest that short β-zipper-like self-binding peptides within the S protein could be identified through combining the peptide scanning and predictive methods, and could be exploited as biochemical detection reagents for viral infection. Copyright © 2018. Published by Elsevier Ltd.

Ion componsition of zipper events

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

Kaye, S.M.; Shelley, E.G.; Sharp, R.D.

1981-05-01

A class of ion distributions has recently been identified by Fennell et al. (this issue). The distributions are composed of two components, a low-energy component with peak fluxes directed along the field line and a high-energy component with peak fluxes in the perpendicular direction. The transiton between the two components occur over a very narrow range of energies but can occur anywhere between approximately several hundred electron volts and 20 keV. Because of the appearance of this distribution on an energy versus time spectrogram, the ion events have been called zippers. The purpose of this report is to examine themore » mass composition of the zipper events. We find that the low-energy and parallel component is composed primarily of O/sup +/, with, to a lesser degree, H/sup +/ and a trace of He/sup +/. The high-energy and perpendicular component is predominantly H/sup +/, with the relative abundances of O/sup +/ and He/sup +/ down from those of the low-energy component by a factor of approx.10. These results suggest that whereas the low-energy component is probably ionospheric in origin, the source of the high-energy components is most probably the plsamasheet.« less

Capsicum annuum homeobox 1 (CaHB1) is a nuclear factor that has roles in plant development, salt tolerance, and pathogen defense.

PubMed

Oh, Sang-Keun; Yoon, Joonseon; Choi, Gyung Ja; Jang, Hyun A; Kwon, Suk-Yoon; Choi, Doil

2013-12-06

Homeodomain-leucine zipper (HD-Zip) family proteins are unique to plants, but little is known about their role in defense responses. CaHB1 is a nuclear factor in peppers, belonging to subfamily II of HD-Zip proteins. Here, we determined the role of CaHB1 in the defense response. CaHB1 expression was induced when pepper plants were challenged with Phytophthora capsici, a plant pathogen to which peppers are susceptible, or environmental stresses such as drought and salt stimuli. CaHB1 was also highly expressed in pepper leaves following application of SA, whereas ethephon and MeJA had a moderate effect. To further investigate the function of CaHB1 in plants, we performed gain-of-function study by overexpression of CaHB1 in tomato. CaHB1-transgenic tomatoes showed significant growth enhancement including increased leaf thickness and enlarged cell size (1.8-fold larger than control plants). Microscopic analysis revealed that leaves from CaHB1-transgenic plants had thicker cell walls and cuticle layers than those from controls. Moreover, CaHB1-transgenic plants displayed enhanced resistance against Phytophthora infestans and increased tolerance to salt stress. Additionally, RT-PCR analysis of CaHB1-transgenic tomatoes revealed constitutive up-regulation of multiple genes involved in plant defense and osmotic stress. Therefore, our findings suggest roles for CaHB1 in development, salt stress, and pathogen defense. Copyright © 2013 Elsevier Inc. All rights reserved.

Spectrophotometry of Peculiar B-Stars and A-Stars - Part Nine - HD5797 HD12288 9-TAURI HD81009 HD111133 33-LIBRAE and HD216533

NASA Astrophysics Data System (ADS)

Adelman, S. J.

1981-02-01

Optical region spectrophotometry of λλ3300-7100 is presented for seven sharp-lined peculiar A stars: HD 5797, HD 12288, 9 Tauri, HD 81009, HD 111133, 33 Librae, and HD 216533. Many of proposed periods in the literature are questioned. Some of the deviations from the predictions of normal stellar atmospheres suggest that such continua are only remotely related to those of peculiar A stars.

Zipper plot: visualizing transcriptional activity of genomic regions.

PubMed

Avila Cobos, Francisco; Anckaert, Jasper; Volders, Pieter-Jan; Everaert, Celine; Rombaut, Dries; Vandesompele, Jo; De Preter, Katleen; Mestdagh, Pieter

2017-05-02

Reconstructing transcript models from RNA-sequencing (RNA-seq) data and establishing these as independent transcriptional units can be a challenging task. Current state-of-the-art tools for long non-coding RNA (lncRNA) annotation are mainly based on evolutionary constraints, which may result in false negatives due to the overall limited conservation of lncRNAs. To tackle this problem we have developed the Zipper plot, a novel visualization and analysis method that enables users to simultaneously interrogate thousands of human putative transcription start sites (TSSs) in relation to various features that are indicative for transcriptional activity. These include publicly available CAGE-sequencing, ChIP-sequencing and DNase-sequencing datasets. Our method only requires three tab-separated fields (chromosome, genomic coordinate of the TSS and strand) as input and generates a report that includes a detailed summary table, a Zipper plot and several statistics derived from this plot. Using the Zipper plot, we found evidence of transcription for a set of well-characterized lncRNAs and observed that fewer mono-exonic lncRNAs have CAGE peaks overlapping with their TSSs compared to multi-exonic lncRNAs. Using publicly available RNA-seq data, we found more than one hundred cases where junction reads connected protein-coding gene exons with a downstream mono-exonic lncRNA, revealing the need for a careful evaluation of lncRNA 5'-boundaries. Our method is implemented using the statistical programming language R and is freely available as a webtool.

Zipping dielectric elastomer actuators: characterization, design and modeling

NASA Astrophysics Data System (ADS)

Maffli, L.; Rosset, S.; Shea, H. R.

2013-10-01

We report on miniature dielectric elastomer actuators (DEAs) operating in zipping mode with an analytical model that predicts their behavior. Electrostatic zipping is a well-known mechanism in silicon MEMS to obtain large deformations and forces at lower voltages than for parallel plate electrostatic actuation. We extend this concept to DEAs, which allows us to obtain much larger out-of-plane displacements compared to silicon thanks to the softness of the elastomer membrane. We study experimentally the effect of sidewall angles and elastomer prestretch on 2.3 mm diameter actuators with PDMS membranes. With 15° and 22.5° sidewall angles, the devices zip in a bistable manner down 300 μm to the bottom of the chambers. The highly tunable bistable behavior is controllable by both chamber geometry and membrane parameters. Other specific characteristics of zipping DEAs include well-controlled deflected shape, tunable displacement versus voltage characteristics to virtually any shape, including multi-stable modes, sealing of embedded holes or channels for valving action and the reduction of the operating voltage. These properties make zipping DEAs an excellent candidate for applications such as integrated microfluidics actuators or Braille displays.

bZIP transcription factor SmJLB1 regulates autophagy-related genes Smatg8 and Smatg4 and is required for fruiting-body development and vegetative growth in Sordaria macrospora.

PubMed

Voigt, Oliver; Herzog, Britta; Jakobshagen, Antonia; Pöggeler, Stefanie

2013-12-01

Autophagy is a precisely controlled degradation process in eukaryotic cells, during which the bulk of the cytoplasm is engulfed by a double membrane vesicle, the autophagosome. Fusion of the autophagosome with the vacuole leads to breakdown of its contents, such as proteins and organelles, and the recycling of nutrients. Earlier studies of autophagic genes of the core autophagic machinery in the filamentous ascomycete Sordaria macrospora elucidated the impact of autophagy on fungal viability, vegetative growth and fruiting-body development. To gain further knowledge about the regulation of autophagy in S. macrospora, we analyzed the function of the bZIP transcription factor SmJLB1, a homolog of the Podospora anserina basic zipper-type transcription factor induced during incompatibility 4 (IDI-4) and the Aspergillus nidulans transcription factor jun-like bZIP A (JlbA). Generation of the homokaryotic deletion mutant demonstrated S. macrospora Smjlb1 is associated with autophagy-dependent processes. Deletion of Smjlb1 abolished fruiting-body formation and impaired vegetative growth. SmJLB1 is localized to the cytoplasm and to nuclei. Quantitative real-time PCR experiments revealed an upregulated expression of autophagy-related genes Smatg8 and Smatg4 in the Smjlb1 deletion mutant, suggesting a transcriptional repression function of SmJLB1. Copyright © 2013 Elsevier Inc. All rights reserved.

ZIP4 silencing improves bone loss in pancreatic cancer

PubMed Central

Yang, Jingxuan; Ding, Hao; LeBrun, Drake; Ding, Kai; Houchen, Courtney W.; Postier, Russell G.; Ambrose, Catherine G.; Li, Zhaoshen; Bi, Xiaohong; Li, Min

2015-01-01

Metabolic bone disorders are associated with several types of human cancers. Pancreatic cancer patients usually suffer from severe nutrition deficiency, muscle wasting, and loss of bone mass. We have previously found that silencing of a zinc transporter ZIP4 prolongs the survival and reduces the severity of the cachexia in vivo. However, the role of ZIP4 in the pancreatic cancer related bone loss remains unknown. In this study we investigated the effect of ZIP4 knockdown on the bone structure, composition and mechanical properties of femurs in an orthotopic xenograft mouse model. Our data showed that silencing of ZIP4 resulted in increased bone tissue mineral density, decreased bone crystallinity and restoration of bone strength through the RANK/RANKL pathway. The results further support the impact of ZIP4 on the progression of pancreatic cancer, and suggest its potential significance as a therapeutic target for treating patients with such devastating disease and cancer related disorders. PMID:26305676

It's (Zipped) in the Bag

ERIC Educational Resources Information Center

Moyer, Richard H.; Everett, Susan A.

2011-01-01

Plastic baggies, especially the sealable variety, seem to be a ubiquitous part of human culture. The zipper-type seal on plastic baggies is an example of an unappreciated engineering accomplishment that is relevant to everyday life. In fact, the challenge of fastening two pieces together probably dates back to the making of tools and clothing by…

Temporary abdominal closure with zipper-mesh device for management of intra-abdominal sepsis.

PubMed

Utiyama, Edivaldo Massazo; Pflug, Adriano Ribeiro Meyer; Damous, Sérgio Henrique Bastos; Rodrigues, Adilson Costa; Montero, Edna Frasson de Souza; Birolini, Claudio Augusto Vianna

2015-01-01

to present our experience with scheduled reoperations in 15 patients with intra-abdominal sepsis. we have applied a more effective technique consisting of temporary abdominal closure with a nylon mesh sheet containing a zipper. We performed reoperations in the operating room under general anesthesia at an average interval of 84 hours. The revision consisted of debridement of necrotic material and vigorous lavage of the involved peritoneal area. The mean age of patients was 38.7 years (range, 15 to 72 years); 11 patients were male, and four were female. forty percent of infections were due to necrotizing pancreatitis. Sixty percent were due to perforation of the intestinal viscus secondary to inflammation, vascular occlusion or trauma. We performed a total of 48 reoperations, an average of 3.2 surgeries per patient. The mesh-zipper device was left in place for an average of 13 days. An intestinal ostomy was present adjacent to the zipper in four patients and did not present a problem for patient management. Mortality was 26.6%. No fistulas resulted from this technique. When intra-abdominal disease was under control, the mesh-zipper device was removed, and the fascia was closed in all patients. In three patients, the wound was closed primarily, and in 12 it was allowed to close by secondary intent. Two patients developed hernia; one was incisional and one was in the drain incision. the planned reoperation for manual lavage and debridement of the abdomen through a nylon mesh-zipper combination was rapid, simple, and well-tolerated. It permitted effective management of severe septic peritonitis, easy wound care and primary closure of the abdominal wall.

The bZIP transcription factor PfZipA regulates secondary metabolism and oxidative stress response in the plant endophytic fungus Pestalotiopsis fici.

PubMed

Wang, Xiuna; Wu, Fan; Liu, Ling; Liu, Xingzhong; Che, Yongsheng; Keller, Nancy P; Guo, Liyun; Yin, Wen-Bing

2015-08-01

The bZIP transcription factors are conserved in all eukaryotes and play critical roles in organismal responses to environmental challenges. In filamentous fungi, several lines of evidence indicate that secondary metabolism (SM) is associated with oxidative stress mediated by bZIP proteins. Here we uncover a connection with a bZIP protein and oxidative stress induction of SM in the plant endophytic fungus Pestalotiopsis fici. A homology search of the P. fici genome with the bZIP protein RsmA, involved in SM and the oxidative stress response in Aspergillus nidulans, identified PfZipA. Deletion of PfzipA resulted in a strain that displayed resistant to the oxidative reagents tert-butylhydroperoxide (tBOOH), diamide, and menadione sodium bisulfite (MSB), but increased sensitivity to H2O2 as compared to wild type (WT). Secondary metabolite production presented a complex pattern dependent on PfzipA and oxidative reagents. Without oxidative treatment, the ΔPfzipA strain produced less isosulochrin and ficipyroneA than WT; addition of tBOOH further decreased production of iso-A82775C and pestaloficiol M in ΔPfzipA; diamide treatment resulted in equivalent production of isosulochrin and ficipyroneA in the two strains; MSB treatment further decreased production of RES1214-1 and iso-A82775C but increased pestaloficiol M production in the mutant; and H2O2 treatment resulted in enhanced production of isosulochrin, RES1214-1 and pestheic acid but decreased ficipyroneA and pestaloficiol M in ΔPfzipA compared to WT. Our results suggest that PfZipA regulation of SM is modified by oxidative stress pathways and provide insights into a possible role of PfZipA in mediating SM synthesis in the endophytic lifestyle of P. fici. Copyright © 2015 Elsevier Inc. All rights reserved.

Chemical analysis of three barium stars: HD 51959, HD 88035, and HD 121447

NASA Astrophysics Data System (ADS)

Karinkuzhi, Drisya; Goswami, Aruna; Sridhar, Navin; Masseron, Thomas; Purandardas, Meenakshi

2018-05-01

We present elemental abundance results from high-resolution spectral analysis of three nitrogen-enhanced barium stars. The analysis is based on spectra obtained with the fibre-fed extended range optical spectrograph attached to 1.52 m telescope at European Southern Observatory, Chile. The spectral resolution is R ˜ 48,000 and the spectral coverage spans from 3500 to 9000Å . For the objects HD 51959 and HD 88035, we present the first-time abundance analyses results. Although a few studies are available in literature on the object HD 121447, the results are significantly different from each other. We have therefore carried out a detailed chemical composition study for this object based on a high-resolution spectrum with high S/N ratio, for a better understanding of the origin of the abundance patterns observed in this star. Stellar atmospheric parameters, the effective temperature, surface gravity, microturbulence, and metallicity of the stars are determined from the local thermodynamic equilibrium analysis using model atmospheres. The metallicities of HD 51959 and HD 88035 are found to be near-solar; they exhibit enhanced abundances of neutron-capture elements. HD 121447 is found to be moderately metal-poor with [Fe/H] = -0.65. While carbon is near-solar in the other two objects, HD 121447 shows carbon enhancement at a level, [C/Fe] = 0.82. Neutron-capture elements are highly enhanced with [X/Fe] > 2 (X: Ba, La, Pr, Nd, Sm) in this object. The α- and iron-peak elements show abundances very similar to field giants with the same metallicity. From kinematic analysis all the three objects are found to be members of thin disc population with a high probability of 0.99, 0.99, and 0.92 for HD 51959, HD 88035, and HD 121447, respectively.

Weekly infusional high-dose fluorouracil (HD-FU), HD-FU plus folinic acid (HD-FU/FA), or HD-FU/FA plus biweekly cisplatin in advanced gastric cancer: randomized phase II trial 40953 of the European Organisation for Research and Treatment of Cancer Gastrointestinal Group and the Arbeitsgemeinschaft Internistische Onkologie.

PubMed

Lutz, Manfred P; Wilke, Hansjochen; Wagener, D J Theo; Vanhoefer, Udo; Jeziorski, Krzysztof; Hegewisch-Becker, Susanna; Balleisen, Leopold; Joossens, Eric; Jansen, Rob L; Debois, Muriel; Bethe, Ullrich; Praet, Michel; Wils, Jacques; Van Cutsem, Eric

2007-06-20

This multicentric, randomized, two-stage phase II trial evaluated three simplified weekly infusional regimens of fluorouracil (FU) or FU plus folinic acid (FA) and cisplatin (Cis) with the aim to select a regimen for future phase III trials. A total of 145 patients with advanced gastric cancer where randomly assigned to weekly FU 3,000 mg/m2/24 hours (HD-FU), FU 2,600 mg/m2/24 hours plus dl-FA 500 mg/m2 or l-FA 250 mg/m2 (HD-FU/FA), or FU 2000 mg/m2/24 hours plus FA plus biweekly Cis 50 mg/m2, each administered for 6 weeks with a 1-week rest. The primary end point was the response rate. Confirmed responses were observed in 6.1% (two of 33) of the eligible patients treated with HD-FU, in 25% (12 of 48, including one complete remission [CR]) with HD-FU/FA, and in 45.7% (21 of 46, including four CRs) with HD-FU/FA/Cis. The HD-FU arm was closed after stage 1 because the required minimum number of responses was not met. The median progression-free survival of all patients in the HD-FU, HD-FU/FA, and HD-FU/FA/Cis arm was 1.9, 4.0, and 6.1 months, respectively. The median overall survival was 7.1, 8.9, and 9.7 months, and the survival rate at 1 year was 24.3%, 30.3%, and 45.3%, respectively. Grade 4 toxicities were rare. The most relevant grade 3/4 toxicities were neutropenia in 1.9%, 5.4%, and 19.6%, and diarrhea in 2.7%, 1.9%, and 3.9% of the cycles in the HD-FU, HD-FU/FA, and HD-/FU/Cis arms, respectively. Weekly infusional FU/FA plus biweekly Cis is effective and safe in patients with gastric cancer.

Structural insights of ZIP4 extracellular domain critical for optimal zinc transport

NASA Astrophysics Data System (ADS)

Zhang, Tuo; Sui, Dexin; Hu, Jian

2016-06-01

The ZIP zinc transporter family is responsible for zinc uptake from the extracellular milieu or intracellular vesicles. The LIV-1 subfamily, containing nine out of the 14 human ZIP proteins, is featured with a large extracellular domain (ECD). The critical role of the ECD is manifested by disease-causing mutations on ZIP4, a representative LIV-1 protein. Here we report the first crystal structure of a mammalian ZIP4-ECD, which reveals two structurally independent subdomains and an unprecedented dimer centred at the signature PAL motif. Structure-guided mutagenesis, cell-based zinc uptake assays and mapping of the disease-causing mutations indicate that the two subdomains play pivotal but distinct roles and that the bridging region connecting them is particularly important for ZIP4 function. These findings lead to working hypotheses on how ZIP4-ECD exerts critical functions in zinc transport. The conserved dimeric architecture in ZIP4-ECD is also demonstrated to be a common structural feature among the LIV-1 proteins.

Evolutionary Descent of Prion Genes from the ZIP Family of Metal Ion Transporters

PubMed Central

Schmitt-Ulms, Gerold; Ehsani, Sepehr; Watts, Joel C.; Westaway, David; Wille, Holger

2009-01-01

In the more than twenty years since its discovery, both the phylogenetic origin and cellular function of the prion protein (PrP) have remained enigmatic. Insights into a possible function of PrP may be obtained through the characterization of its molecular neighborhood in cells. Quantitative interactome data demonstrated the spatial proximity of two metal ion transporters of the ZIP family, ZIP6 and ZIP10, to mammalian prion proteins in vivo. A subsequent bioinformatic analysis revealed the unexpected presence of a PrP-like amino acid sequence within the N-terminal, extracellular domain of a distinct sub-branch of the ZIP protein family that includes ZIP5, ZIP6 and ZIP10. Additional structural threading and orthologous sequence alignment analyses argued that the prion gene family is phylogenetically derived from a ZIP-like ancestral molecule. The level of sequence homology and the presence of prion protein genes in most chordate species place the split from the ZIP-like ancestor gene at the base of the chordate lineage. This relationship explains structural and functional features found within mammalian prion proteins as elements of an ancient involvement in the transmembrane transport of divalent cations. The phylogenetic and spatial connection to ZIP proteins is expected to open new avenues of research to elucidate the biology of the prion protein in health and disease. PMID:19784368

α-SNAP Interferes with the Zippering of the SNARE Protein Membrane Fusion Machinery

PubMed Central

Park, Yongsoo; Vennekate, Wensi; Yavuz, Halenur; Preobraschenski, Julia; Hernandez, Javier M.; Riedel, Dietmar; Walla, Peter Jomo; Jahn, Reinhard

2014-01-01

Neuronal exocytosis is mediated by soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins. Before fusion, SNARE proteins form complexes bridging the membrane followed by assembly toward the C-terminal membrane anchors, thus initiating membrane fusion. After fusion, the SNARE complex is disassembled by the AAA-ATPase N-ethylmaleimide-sensitive factor that requires the cofactor α-SNAP to first bind to the assembled SNARE complex. Using chromaffin granules and liposomes we now show that α-SNAP on its own interferes with the zippering of membrane-anchored SNARE complexes midway through the zippering reaction, arresting SNAREs in a partially assembled trans-complex and preventing fusion. Intriguingly, the interference does not result in an inhibitory effect on synaptic vesicles, suggesting that membrane properties also influence the final outcome of α-SNAP interference with SNARE zippering. We suggest that binding of α-SNAP to the SNARE complex affects the ability of the SNARE complex to harness energy or transmit force to the membrane. PMID:24778182

The bZIP transcription factor MdHY5 regulates anthocyanin accumulation and nitrate assimilation in apple.

PubMed

An, Jian-Ping; Qu, Feng-Jia; Yao, Ji-Fang; Wang, Xiao-Na; You, Chun-Xiang; Wang, Xiao-Fei; Hao, Yu-Jin

2017-01-01

The basic leucine zipper (bZIP) transcription factor HY5 plays a multifaceted role in plant growth and development. Here the apple MdHY5 gene was cloned based on its homology with Arabidopsis HY5 . Expression analysis demonstrated that MdHY5 transcription was induced by light and abscisic acid treatments. Electrophoretic mobility shift assays and transient expression assays subsequently showed that MdHY5 positively regulated both its own transcription and that of MdMYB10 by binding to E-box and G-box motifs, respectively. Furthermore, we obtained transgenic apple calli that overexpressed the MdHY5 gene, and apple calli coloration assays showed that MdHY5 promoted anthocyanin accumulation by regulating expression of the MdMYB10 gene and downstream anthocyanin biosynthesis genes. In addition, the transcript levels of a series of nitrate reductase genes and nitrate uptake genes in both wild-type and transgenic apple calli were detected. In association with increased nitrate reductase activities and nitrate contents, the results indicated that MdHY5 might be an important regulator in nutrient assimilation. Taken together, these results indicate that MdHY5 plays a vital role in anthocyanin accumulation and nitrate assimilation in apple.

Using ZIP Code Business Patterns Data to Measure Alcohol Outlet Density

PubMed Central

Matthews, Stephen A.; McCarthy, John D.; Rafail, Patrick S.

2014-01-01

Some states maintain high-quality alcohol outlet databases but quality varies by state, making comprehensive comparative analysis across US communities difficult. This study assesses the adequacy of using ZIP Code Business Patterns (ZIP-BP) data on establishments as estimates of the number of alcohol outlets by ZIP code. Specifically we compare ZIP-BP alcohol outlet counts with high-quality data from state and local records surrounding 44 college campus communities across 10 states plus the District of Columbia. Results show that a composite measure is strongly correlated (R=0.89) with counts of alcohol outlets generated from official state records. Analyses based on Generalized Estimation Equation models show that community and contextual factors have little impact on the concordance between the two data sources. There are also minimal inter-state differences in the level of agreement. To validate the use of a convenient secondary data set (ZIP-BP) it is important to have a high correlation with the more complex, high quality and more costly data product (i.e., datasets based on the acquisition and geocoding of state and local records) and then to clearly demonstrate that the discrepancy between the two to be unrelated to relevant explanatory variables. Thus our overall findings support the adequacy of using a conveniently available data set (ZIP-BP data) to estimate alcohol outlet densities in ZIP code areas in future research. PMID:21411233

NEWLY DISCOVERED PLANETS ORBITING HD 5319, HD 11506, HD 75784 AND HD 10442 FROM THE N2K CONSORTIUM

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

Giguere, Matthew J.; Fischer, Debra A.; Brewer, John M.

2015-01-20

Initially designed to discover short-period planets, the N2K campaign has since evolved to discover new worlds at large separations from their host stars. Detecting such worlds will help determine the giant planet occurrence at semi-major axes beyond the ice line, where gas giants are thought to mostly form. Here we report four newly discovered gas giant planets (with minimum masses ranging from 0.4 to 2.1 M {sub Jup}) orbiting stars monitored as part of the Next 2000 target stars (N2K) Doppler Survey program. Two of these planets orbit stars already known to host planets: HD 5319 and HD 11506. Themore » remaining discoveries reside in previously unknown planetary systems: HD 10442 and HD 75784. The refined orbital period of the inner planet orbiting HD 5319 is 641 days. The newly discovered outer planet orbits in 886 days. The large masses combined with the proximity to a 4:3 mean motion resonance make this system a challenge to explain with current formation and migration theories. HD 11506 has one confirmed planet, and here we confirm a second. The outer planet has an orbital period of 1627.5 days, and the newly discovered inner planet orbits in 223.6 days. A planet has also been discovered orbiting HD 75784 with an orbital period of 341.7 days. There is evidence for a longer period signal; however, several more years of observations are needed to put tight constraints on the Keplerian parameters for the outer planet. Lastly, an additional planet has been detected orbiting HD 10442 with a period of 1043 days.« less

Polarized Disk Emission from Herbig Ae/Be Stars Observed Using Gemini Planet Imager: HD 144432, HD 150193, HD 163296, and HD 169142

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

Monnier, John D.; Aarnio, Alicia; Adams, Fred C.

In order to look for signs of ongoing planet formation in young disks, we carried out the first J -band polarized emission imaging of the Herbig Ae/Be stars HD 150193, HD 163296, and HD 169142 using the Gemini Planet Imager, along with new H band observations of HD 144432. We confirm the complex “double ring” structure for the nearly face-on system HD 169142 first seen in H -band, finding the outer ring to be substantially redder than the inner one in polarized intensity. Using radiative transfer modeling, we developed a physical model that explains the full spectral energy distribution andmore » J - and H -band surface brightness profiles, suggesting that the differential color of the two rings could come from reddened starlight traversing the inner wall and may not require differences in grain properties. In addition, we clearly detect an elongated, off-center ring in HD 163296 (MWC 275), locating the scattering surface to be 18 au above the midplane at a radial distance of 77 au, co-spatial with a ring seen at 1.3 mm by ALMA linked to the CO snow line. Lastly, we report a weak tentative detection of scattered light for HD 150193 (MWC 863) and a non-detection for HD 144432; the stellar companion known for each of these targets has likely disrupted the material in the outer disk of the primary star. For HD 163296 and HD 169142, the prominent outer rings we detect could be evidence for giant planet formation in the outer disk or a manifestation of large-scale dust growth processes possibly related to snow-line chemistry.« less

Recovery from temporary endoplasmic reticulum stress in plants relies on the tissue-specific and largely independent roles of bZIP28 and bZIP60, as well as an antagonizing function of BAX-Inhibitor 1 upon the pro-adaptive signaling mediated by bZIP28.

PubMed

Ruberti, Cristina; Lai, YaShiuan; Brandizzi, Federica

2018-01-01

The unfolded protein response (UPR) is an ancient signaling pathway that commits to life-or-death outcomes in response to proteotoxic stress in the endoplasmic reticulum (ER). In plants, the membrane-tethered transcription factor bZIP28 and the ribonuclease-kinase IRE1 along with its splicing target, bZIP60, govern the two cytoprotective UPR signaling pathways known to date. The conserved ER membrane-associated BAX inhibitor 1 (BI1) modulates ER stress-induced programmed cell death through yet-unknown mechanisms. Despite the significance of the UPR for cell homeostasis, in plants the regulatory circuitry underlying ER stress resolution is still largely unmapped. To gain insights into the coordination of plant UPR strategies, we analyzed the functional relationship of the UPR modulators through the analysis of single and higher order mutants of IRE1, bZIP60, bZIP28 and BI1 in experimental conditions causing either temporary or chronic ER stress. We established a functional duality of bZIP28 and bZIP60, as they exert partially independent tissue-specific roles in recovery from ER stress, but redundantly actuate survival strategies in chronic ER stress. We also discovered that BI1 attenuates the pro-survival function of bZIP28 in ER stress resolution and, differently to animal cells, it does not temper the ribonuclease activity of inositol-requiring enzyme 1 (IRE1) under temporary ER stress. Together these findings reveal a functional independence of bZIP28 and bZIP60 in plant UPR, and identify an antagonizing role of BI1 in the pro-adaptive signaling mediated by bZIP28, bringing to light the distinctive complexity of the unfolded protein response (UPR) in plants. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

Molecular pathogenesis of Spondylocheirodysplastic Ehlers-Danlos syndrome caused by mutant ZIP13 proteins

PubMed Central

Bin, Bum-Ho; Hojyo, Shintaro; Hosaka, Toshiaki; Bhin, Jinhyuk; Kano, Hiroki; Miyai, Tomohiro; Ikeda, Mariko; Kimura-Someya, Tomomi; Shirouzu, Mikako; Cho, Eun-Gyung; Fukue, Kazuhisa; Kambe, Taiho; Ohashi, Wakana; Kim, Kyu-Han; Seo, Juyeon; Choi, Dong-Hwa; Nam, Yeon-Ju; Hwang, Daehee; Fukunaka, Ayako; Fujitani, Yoshio; Yokoyama, Shigeyuki; Superti-Furga, Andrea; Ikegawa, Shiro; Lee, Tae Ryong; Fukada, Toshiyuki

2014-01-01

The zinc transporter protein ZIP13 plays critical roles in bone, tooth, and connective tissue development, and its dysfunction is responsible for the spondylocheirodysplastic form of Ehlers-Danlos syndrome (SCD-EDS, OMIM 612350). Here, we report the molecular pathogenic mechanism of SCD-EDS caused by two different mutant ZIP13 proteins found in human patients: ZIP13G64D, in which Gly at amino acid position 64 is replaced by Asp, and ZIP13ΔFLA, which contains a deletion of Phe-Leu-Ala. We demonstrated that both the ZIP13G64D and ZIP13ΔFLA protein levels are decreased by degradation via the valosin-containing protein (VCP)-linked ubiquitin proteasome pathway. The inhibition of degradation pathways rescued the protein expression levels, resulting in improved intracellular Zn homeostasis. Our findings uncover the pathogenic mechanisms elicited by mutant ZIP13 proteins. Further elucidation of these degradation processes may lead to novel therapeutic targets for SCD-EDS. PMID:25007800

The regulatory network of ThbZIP1 in response to abscisic acid treatment

PubMed Central

Ji, Xiaoyu; Liu, Guifeng; Liu, Yujia; Nie, Xianguang; Zheng, Lei; Wang, Yucheng

2015-01-01

Previously, a bZIP transcription factor from Tamarix hispida, ThbZIP1, was characterized: plants overexpressing ThbZIP1 displayed improved salt stress tolerance but were sensitive to abscisic acid (ABA). In the current study, we further characterized the regulatory network of ThbZIP1 and the mechanism of ABA sensitivity mediated by ThbZIP1. An ABF transcription factor from T. hispida, ThABF1, directly regulates the expression of ThbZIP1. Microarray analysis identified 1662 and 1609 genes that were respectively significantly upregulated or downregulated by ThbZIP1 when exposed to ABA. Gene ontology (GO) analysis showed that the processes including “response to stimulus,” “catalytic activity,” “binding function,” and “metabolic process” were highly altered in ThbZIP1 expressing plants exposed to ABA. The gene expression in ThbZIP1 transformed plants were compared between exposed to ABA and salt on the genome scale. Genes differentially regulated by both salt and ABA treatment only accounted for 9.75% of total differentially regulated genes. GO analysis showed that structural molecule activity, organelle part, membrane-enclosed lumen, reproduction, and reproductive process are enhanced by ABA but inhibited by salt stress. Conversely, immune system and multi-organism process were improved by salt but inhibited by ABA. Transcription regulator activity, enzyme regulator activity, and developmental process were significantly altered by ABA but were not affected by salt stress. Our study provides insights into how ThbZIP1 mediates ABA and salt stress response at the molecular level. PMID:25713576

Using ZIP code business patterns data to measure alcohol outlet density.

PubMed

Matthews, Stephen A; McCarthy, John D; Rafail, Patrick S

2011-07-01

Some states maintain high-quality alcohol outlet databases but quality varies by state, making comprehensive comparative analysis across US communities difficult. This study assesses the adequacy of using ZIP Code Business Patterns (ZIP-BP) data on establishments as estimates of the number of alcohol outlets by ZIP code. Specifically we compare ZIP-BP alcohol outlet counts with high-quality data from state and local records surrounding 44 college campus communities across 10 states plus the District of Columbia. Results show that a composite measure is strongly correlated (R=0.89) with counts of alcohol outlets generated from official state records. Analyses based on Generalized Estimation Equation models show that community and contextual factors have little impact on the concordance between the two data sources. There are also minimal inter-state differences in the level of agreement. To validate the use of a convenient secondary data set (ZIP-BP) it is important to have a high correlation with the more complex, high quality and more costly data product (i.e., datasets based on the acquisition and geocoding of state and local records) and then to clearly demonstrate that the discrepancy between the two to be unrelated to relevant explanatory variables. Thus our overall findings support the adequacy of using a conveniently available data set (ZIP-BP data) to estimate alcohol outlet densities in ZIP code areas in future research. Copyright © 2011 Elsevier Ltd. All rights reserved.

SdAb heterodimer formation using leucine zippers

NASA Astrophysics Data System (ADS)

Goldman, Ellen R.; Anderson, George P.; Brozozog-Lee, P. Audrey; Zabetakis, Dan

2013-05-01

Single domain antibodies (sdAb) are variable domains cloned from camel, llama, or shark heavy chain only antibodies, and are among the smallest known naturally derived antigen binding fragments. SdAb derived from immunized llamas are able to bind antigens with high affinity, and most are capable of refolding after heat or chemical denaturation to bind antigen again. We hypothesized that the ability to produce heterodimeric sdAb would enable reagents with the robust characteristics of component sdAb, but with dramatically improved overall affinity through increased avidity. Previously we had constructed multimeric sdAb by genetically linking sdAb that bind non-overlapping epitopes on the toxin, ricin. In this work we explored a more flexible approach; the construction of multivalent binding reagents using multimerization domains. We expressed anti-ricin sdAb that recognize different epitopes on the toxin as fusions with differently charged leucine zippers. When the initially produced homodimers are mixed the leucine zipper domains will pair to produce heterodimers. We used fluorescence resonance energy transfer to confirm heterodimer formation. Surface plasmon resonance, circular dichroism, enzyme linked immunosorbent assays, and fluid array assays were used to characterize the multimer constructs, and evaluate their utility in toxin detection.

α-SNAP interferes with the zippering of the SNARE protein membrane fusion machinery.

PubMed

Park, Yongsoo; Vennekate, Wensi; Yavuz, Halenur; Preobraschenski, Julia; Hernandez, Javier M; Riedel, Dietmar; Walla, Peter Jomo; Jahn, Reinhard

2014-06-06

Neuronal exocytosis is mediated by soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins. Before fusion, SNARE proteins form complexes bridging the membrane followed by assembly toward the C-terminal membrane anchors, thus initiating membrane fusion. After fusion, the SNARE complex is disassembled by the AAA-ATPase N-ethylmaleimide-sensitive factor that requires the cofactor α-SNAP to first bind to the assembled SNARE complex. Using chromaffin granules and liposomes we now show that α-SNAP on its own interferes with the zippering of membrane-anchored SNARE complexes midway through the zippering reaction, arresting SNAREs in a partially assembled trans-complex and preventing fusion. Intriguingly, the interference does not result in an inhibitory effect on synaptic vesicles, suggesting that membrane properties also influence the final outcome of α-SNAP interference with SNARE zippering. We suggest that binding of α-SNAP to the SNARE complex affects the ability of the SNARE complex to harness energy or transmit force to the membrane. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

A Novel Alternative Splicing Isoform of Human T-Cell Leukemia Virus Type 1 bZIP Factor (HBZ-SI) Targets Distinct Subnuclear Localization

PubMed Central

Murata, Ken; Hayashibara, Toshihisa; Sugahara, Kazuyuki; Uemura, Akiko; Yamaguchi, Taku; Harasawa, Hitomi; Hasegawa, Hiroo; Tsuruda, Kazuto; Okazaki, Toshiro; Koji, Takehiko; Miyanishi, Takayuki; Yamada, Yasuaki; Kamihira, Shimeru

2006-01-01

Adult T-cell leukemia (ATL) is associated with prior infection with human T-cell leukemia virus type 1 (HTLV-1); however, the mechanism by which HTLV-1 causes adult T-cell leukemia has not been fully elucidated. Recently, a functional basic leucine zipper (bZIP) protein coded in the minus strand of HTLV-1 genome (HBZ) was identified. We report here a novel isoform of the HTLV-1 bZIP factor (HBZ), HBZ-SI, identified by means of reverse transcription-PCR (RT-PCR) in conjunction with 5′ and 3′ rapid amplification of cDNA ends (RACE). HBZ-SI is a 206-amino-acid-long protein and is generated by alternative splicing between part of the HBZ gene and a novel exon located in the 3′ long terminal repeat of the HTLV-1 genome. Consequently, these isoforms share >95% amino acid sequence identity, and differ only at their N termini, indicating that HBZ-SI is also a functional protein. Duplex RT-PCR and real-time quantitative RT-PCR analyses showed that the mRNAs of these isoforms were expressed at equivalent levels in all ATL cell samples examined. Nonetheless, we found by Western blotting that the HBZ-SI protein was preferentially expressed in some ATL cell lines examined. A key finding was obtained from the subcellular localization analyses of these isoforms. Despite their high sequence similarity, each isoform was targeted to distinguishable subnuclear structures. These data show the presence of a novel isoform of HBZ in ATL cells, and in addition, shed new light on the possibility that each isoform may play a unique role in distinct regions in the cell nucleus. PMID:16474156

The Single Needle Lockstitch Machine. [Setting Zippers.] Module 8.

ERIC Educational Resources Information Center

South Carolina State Dept. of Education, Columbia. Office of Vocational Education.

This module on setting zippers, one in a series on the single needle lockstitch sewing machine for student self-study, contains five sections. Each section includes the following parts: an introduction, directions, an objective, learning activities, student information, student self-check, check-out activities, and an instructor's final checklist.…

Resistance of Type 5 chemical protective clothing against nanometric airborne particles: Behavior of seams and zipper.

PubMed

Vinches, Ludwig; Hallé, Stéphane

2017-12-01

In the field of dermal protection, the use of chemical protective clothing (CPC) (including coveralls) are considered as the last barrier against airborne engineered nanomaterials (ENM). In the majority of cases, Type 5 CPC, used against solid particles (ISO 13982-1), perform well against ENM. But in a recent study, a penetration level (PL) of up to 8.5% of polydisperse sodium chloride airborne nanoparticles has been measured. Moreover, in all the previous studies, tests were performed on a sample of protective clothing material without seams or zippers. Thus, the potential for permeation through a zipper or seams has not yet been determined, even though these areas would be privileged entry points for airborne ENM. This work was designed to evaluate the PL of airborne ENM through coveralls and specifically the PL through the seams on different parts of the CPC and the zipper. Eight current models of CPC (Type 5) were selected. The samples were taken from places with and without seams and with a zipper. In some cases, a cover strip can be added to the zipper to enhance its sealing. Polydisperse nanoparticles were generated by nebulization of a sodium chloride solution. A penetration cell was developed to expose the sample to airborne nanometric particles. The NaCl particle concentration in number was measured with an ultrafine particle counter and the PL was defined as the downstream concentration divided by the upstream concentration. The results obtained show that the PL increased significantly in the presence of seams and could reach up to 90% depending on the seam's design. Moreover, this study classifies the different types of seams by their resistance against airborne ENM. As for the penetration of airborne NaCl particles through the zipper, the PL was greatly attenuated by the presence of a cover strip, but only for certain models of coveralls. Finally, the values of the pressure drop were directly linked to the type of seam. All of these conclusions provide

Efficient Proximity Computation Techniques Using ZIP Code Data for Smart Cities †

PubMed Central

Murdani, Muhammad Harist; Hong, Bonghee

2018-01-01

In this paper, we are interested in computing ZIP code proximity from two perspectives, proximity between two ZIP codes (Ad-Hoc) and neighborhood proximity (Top-K). Such a computation can be used for ZIP code-based target marketing as one of the smart city applications. A naïve approach to this computation is the usage of the distance between ZIP codes. We redefine a distance metric combining the centroid distance with the intersecting road network between ZIP codes by using a weighted sum method. Furthermore, we prove that the results of our combined approach conform to the characteristics of distance measurement. We have proposed a general and heuristic approach for computing Ad-Hoc proximity, while for computing Top-K proximity, we have proposed a general approach only. Our experimental results indicate that our approaches are verifiable and effective in reducing the execution time and search space. PMID:29587366

Efficient Proximity Computation Techniques Using ZIP Code Data for Smart Cities †.

PubMed

Murdani, Muhammad Harist; Kwon, Joonho; Choi, Yoon-Ho; Hong, Bonghee

2018-03-24

In this paper, we are interested in computing ZIP code proximity from two perspectives, proximity between two ZIP codes ( Ad-Hoc ) and neighborhood proximity ( Top-K ). Such a computation can be used for ZIP code-based target marketing as one of the smart city applications. A naïve approach to this computation is the usage of the distance between ZIP codes. We redefine a distance metric combining the centroid distance with the intersecting road network between ZIP codes by using a weighted sum method. Furthermore, we prove that the results of our combined approach conform to the characteristics of distance measurement. We have proposed a general and heuristic approach for computing Ad-Hoc proximity, while for computing Top-K proximity, we have proposed a general approach only. Our experimental results indicate that our approaches are verifiable and effective in reducing the execution time and search space.

Role of glucocorticoid-induced leucine zipper (GILZ) in bone acquisition

USDA-ARS?s Scientific Manuscript database

Glucocorticoids (GCs) have both anabolic and catabolic effects on bone. However, no GC anabolic effect mediator has been identified to date. In this report, we provide the first evidence that glucocorticoid-induced leucine zipper (GILZ), a GC anti-inflammatory effect mediator, can enhance bone forma...

'Zipbody' leucine zipper-fused Fab in E. coli in vitro and in vivo expression systems.

PubMed

Ojima-Kato, Teruyo; Fukui, Kansuke; Yamamoto, Hiroaki; Hashimura, Dai; Miyake, Shiro; Hirakawa, Yuki; Yamasaki, Tomomi; Kojima, Takaaki; Nakano, Hideo

2016-04-01

A small antibody fragment, fragment of antigen binding (Fab), is favorable for various immunological assays. However, production efficiency of active Fab in microorganisms depends considerably on the clones. In this study, leucine zipper-peptide pairs that dimerize in parallel (ACID-p1 (LZA)/BASE-p1 (LZB) or c-Jun/c-Fos) were fused to the C-terminus of heavy chain (Hc, VH-CH1) and light chain (Lc, VL-CL), respectively, to accelerate the association of Hc and Lc to form Fab in Escherichia coli in vivo and in vitro expression systems. The leucine zipper-fused Fab named 'Zipbody' was constructed using anti-E. coli O157 monoclonal antibody obtained from mouse hybridoma and produced in both in vitro and in vivo expression systems in an active form, whereas Fab without the leucine zipper fusion was not. Similarly, Zipbody of rabbit monoclonal antibody produced in in vitro expression showed significant activity. The purified, mouse Zipbody produced in the E. coli strain Shuffle T7 Express had specificity toward the antigen; in bio-layer interferometry analysis, the KD value was measured to be 1.5-2.0 × 10(-8) M. These results indicate that leucine zipper fusion to Fab C-termini markedly enhances active Fab formation in E. coli. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Studies of Second Layer Hydrogens on Graphite: Hydrogen/hd/gr and Hd/hd/gr.

NASA Astrophysics Data System (ADS)

Liu, Yuanming

Quasi-adiabatic heat capacity and volumetric vapor pressure isotherm techniques were used to study the thermodynamic properties of monolayer H_2 adsorbed on HD plated graphite (H_2/HD/Gr) and bilayer HD on bare graphite (HD/HD/Gr). Quasielastic neutron scattering (QENS) measurements were performed at the Laboratoire Leon Brillouin (LLB) in Saclay, France, to study the mobility of the bilayer HD films. The three techniques complemented each other. Three types of graphite were used: graphite foam for the heat capacity measurements, more loose and homogeneous graphite 'worms' for the isotherm measurements, and Papyex (similar to Grafoil) with a high surface-to-volume ratio for the QENS measurements. The heat capacity study on the mixture system H_2/HD/Gr is a continuation of the previous study on H_2/D _2/Gr by F. C. Liu et al. The results show three peculiar features which have not been seen in the pure bilayer hydrogen films: a tilted triple line, a distorted liquid(L)-vapor(V) coexistence region, and weak heat capacity anomalies at 10.1K. The triple line tilts backwards, from 6.58K to 6.25K as the H2 coverage increases. The lowest triple point temperature (6.25K) is still higher than both 5.96K of H_2/H _2/Gr (Wiechert et al.) and 5.74K of H_2/D_2/Gr (F. C. Liu et al.). The behavior of the triple line can be semi-quantitatively explained by a model of interlayer mixing which is based on the consideration that interlayer mixing lowers the system's free energy. The distortion of the L-V region and appearance of weak heat capacity anomalies are also believed to be due to interlayer mixing. The heat capacity measurements on HD/HD/Gr show a phase diagram similar to those of H_2 /H_2/MgO, H_2 /H_2/Gr, and 3D van der Waals systems, with the 2D triple and critical points at T _{t} = 8.44K and T_ {c} = 11.45K. The entropy change and heat of fusion at the triple point melting in HD/HD/Gr are comparable with those of H_2/H _2/Gr and D_2/D _2/Gr, but are considerably less

Expanding Actin Rings Zipper the Mouse Embryo for Blastocyst Formation.

PubMed

Zenker, Jennifer; White, Melanie D; Gasnier, Maxime; Alvarez, Yanina D; Lim, Hui Yi Grace; Bissiere, Stephanie; Biro, Maté; Plachta, Nicolas

2018-04-19

Transformation from morula to blastocyst is a defining event of preimplantation embryo development. During this transition, the embryo must establish a paracellular permeability barrier to enable expansion of the blastocyst cavity. Here, using live imaging of mouse embryos, we reveal an actin-zippering mechanism driving this embryo sealing. Preceding blastocyst stage, a cortical F-actin ring assembles at the apical pole of the embryo's outer cells. The ring structure forms when cortical actin flows encounter a network of polar microtubules that exclude F-actin. Unlike stereotypical actin rings, the actin rings of the mouse embryo are not contractile, but instead, they expand to the cell-cell junctions. Here, they couple to the junctions by recruiting and stabilizing adherens and tight junction components. Coupling of the actin rings triggers localized myosin II accumulation, and it initiates a tension-dependent zippering mechanism along the junctions that is required to seal the embryo for blastocyst formation. Copyright © 2018 Elsevier Inc. All rights reserved.

The Survival Motor Neuron Protein Forms Soluble Glycine Zipper Oligomers

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

Martin, Renee; Gupta, Kushol; Ninan, Nisha S.

2012-11-01

The survival motor neuron (SMN) protein forms the oligomeric core of a multiprotein complex that functions in spliceosomal snRNP biogenesis. Loss of function mutations in the SMN gene cause spinal muscular atrophy (SMA), a leading genetic cause of infant mortality. Nearly half of the known SMA patient missense mutations map to the SMN YG-box, a highly conserved oligomerization domain of unknown structure that contains a (YxxG)3 motif. Here, we report that the SMN YG-box forms helical oligomers similar to the glycine zippers found in transmembrane channel proteins. A network of tyrosine-glycine packing between helices drives formation of soluble YG-box oligomers,more » providing a structural basis for understanding SMN oligomerization and for relating defects in oligomerization to the mutations found in SMA patients. These results have important implications for advancing our understanding of SMN function and glycine zipper-mediated helix-helix interactions.« less

RE-VISIT OF HST FUV OBSERVATIONS OF THE HOT-JUPITER SYSTEM HD 209458: NO Si iii DETECTION AND THE NEED FOR COS TRANSIT OBSERVATIONS

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

Ballester, G. E.; Ben-Jaffel, L., E-mail: gilda@lpl.arizona.edu, E-mail: bjaffel@iap.fr

2015-05-10

The discovery of O i atoms and C ii ions in the upper atmosphere of HD 209458b, made with the Hubble Space Telescope Imaging Spectrograph (STIS) using the G140L grating, showed that these heavy species fill an area comparable to the planet’s Roche lobe. The derived ∼10% transit absorption depths require super-thermal processes and/or supersolar abundances. From subsequent Cosmic Origins Spectrograph (COS) observations, C ii absorption was reported with tentative velocity signatures, and absorption by Si iii ions was also claimed in disagreement with a negative STIS G140L detection. Here, we revisit the COS data set showing a severe limitationmore » in the published results from having contrasted the in-transit spectrum against a stellar spectrum averaged from separate observations, at planetary phases 0.27, 0.72, and 0.49. We find variable stellar Si iii and C ii emissions that were significantly depressed not only during transit but also at phase 0.27 compared to phases 0.72 and 0.49. Their respective off-transit 7.5% and 3.1% flux variations are large compared to their reported 8.2 ± 1.4% and 7.8 ± 1.3% transit absorptions. Significant variations also appear in the stellar line shapes, questioning reported velocity signatures. We furthermore present archive STIS G140M transit data consistent with no Si iii absorption, with a negative result of 1.7 ± 18.7 including ∼15% variability. Silicon may still be present at lower ionization states, in parallel with the recent detection of extended magnesium, as Mg i atoms. In this frame, the firm detection of O i and C ii implying solar or supersolar abundances contradicts the recent inference of potential 20–125× subsolar metallicity for HD 209458b.« less

The unusual carbon star HD 59643 - Alternative models

NASA Technical Reports Server (NTRS)

Johnson, H. R.; Eaton, J. A.; Querci, F. R.; Querci, M.; Baumert, J. H.

1988-01-01

A binary model for the carbon star HD 59643 is discussed in which the secondary spectrum is formed in an accretion disk. If this hot, ultraviolet-emitting disk radiates like a 20,000 K black-body, it must be 0.03 solar radii or less across at minimum emission. Large widths of C IV multiplet UV1 on high-resolution spectra indicate its formation in the inner parts of a disk. The semiforbidden C III and Si III lines, however, are much narrower and could be formed in the outer parts of a disk or in the carbon star's chromosphere. The electron density in the region of formation of C III is about 10 to the 10th/cu cm.

Accurate effective temperatures of the metal-poor benchmark stars HD 140283, HD 122563, and HD 103095 from CHARA interferometry

NASA Astrophysics Data System (ADS)

Karovicova, I.; White, T. R.; Nordlander, T.; Lind, K.; Casagrande, L.; Ireland, M. J.; Huber, D.; Creevey, O.; Mourard, D.; Schaefer, G. H.; Gilmore, G.; Chiavassa, A.; Wittkowski, M.; Jofré, P.; Heiter, U.; Thévenin, F.; Asplund, M.

2018-03-01

Large stellar surveys of the Milky Way require validation with reference to a set of `benchmark' stars whose fundamental properties are well determined. For metal-poor benchmark stars, disagreement between spectroscopic and interferometric effective temperatures has called the reliability of the temperature scale into question. We present new interferometric measurements of three metal-poor benchmark stars, HD 140283, HD 122563, and HD 103095, from which we determine their effective temperatures. The angular sizes of all the stars were determined from observations with the PAVO beam combiner at visible wavelengths at the CHARA array, with additional observations of HD 103095 made with the VEGA instrument, also at the CHARA array. Together with photometrically derived bolometric fluxes, the angular diameters give a direct measurement of the effective temperature. For HD 140283, we find θLD = 0.324 ± 0.005 mas, Teff = 5787 ± 48 K; for HD 122563, θLD = 0.926 ± 0.011 mas, Teff = 4636 ± 37 K; and for HD 103095, θLD = 0.595 ± 0.007 mas, Teff = 5140 ± 49 K. Our temperatures for HD 140283 and HD 103095 are hotter than the previous interferometric measurements by 253 and 322 K, respectively. We find good agreement between our temperatures and recent spectroscopic and photometric estimates. We conclude some previous interferometric measurements have been affected by systematic uncertainties larger than their quoted errors.

Hepatic ZIP14-mediated zinc transport is required for adaptation to endoplasmic reticulum stress.

PubMed

Kim, Min-Hyun; Aydemir, Tolunay B; Kim, Jinhee; Cousins, Robert J

2017-07-18

Extensive endoplasmic reticulum (ER) stress damages the liver, causing apoptosis and steatosis despite the activation of the unfolded protein response (UPR). Restriction of zinc from cells can induce ER stress, indicating that zinc is essential to maintain normal ER function. However, a role for zinc during hepatic ER stress is largely unknown despite important roles in metabolic disorders, including obesity and nonalcoholic liver disease. We have explored a role for the metal transporter ZIP14 during pharmacologically and high-fat diet-induced ER stress using Zip14 -/- (KO) mice, which exhibit impaired hepatic zinc uptake. Here, we report that ZIP14-mediated hepatic zinc uptake is critical for adaptation to ER stress, preventing sustained apoptosis and steatosis. Impaired hepatic zinc uptake in Zip14 KO mice during ER stress coincides with greater expression of proapoptotic proteins. ER stress-induced Zip14 KO mice show greater levels of hepatic steatosis due to higher expression of genes involved in de novo fatty acid synthesis, which are suppressed in ER stress-induced WT mice. During ER stress, the UPR-activated transcription factors ATF4 and ATF6α transcriptionally up-regulate Zip14 expression. We propose ZIP14 mediates zinc transport into hepatocytes to inhibit protein-tyrosine phosphatase 1B (PTP1B) activity, which acts to suppress apoptosis and steatosis associated with hepatic ER stress. Zip14 KO mice showed greater hepatic PTP1B activity during ER stress. These results show the importance of zinc trafficking and functional ZIP14 transporter activity for adaptation to ER stress associated with chronic metabolic disorders.

The N-terminal leucine-zipper motif in PTRF/cavin-1 is essential and sufficient for its caveolae-association

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

Wei, Zhuang; Laboratory of System Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031; Zou, Xinle

2015-01-16

Highlight: • The N-terminal leucine-zipper motif in PTRF/cavin-1 determines caveolar association. • Different cellular localization of PTRF/cavin-1 influences its serine 389 and 391 phosphorylation state. • PTRF/cavin-1 regulates cell motility via its caveolar association. - Abstract: PTRF/cavin-1 is a protein of two lives. Its reported functions in ribosomal RNA synthesis and in caveolae formation happen in two different cellular locations: nucleus vs. plasma membrane. Here, we identified that the N-terminal leucine-zipper motif in PTRF/cavin-1 was essential for the protein to be associated with caveolae in plasma membrane. It could counteract the effect of nuclear localization sequence in the molecule (AAmore » 235–251). Deletion of this leucine-zipper motif from PTRF/cavin-1 caused the mutant to be exclusively localized in nuclei. The fusion of this leucine-zipper motif with histone 2A, which is a nuclear protein, could induce the fusion protein to be exported from nucleus. Cell migration was greatly inhibited in PTRF/cavin-1{sup −/−} mouse embryonic fibroblasts (MEFs). The inhibited cell motility could only be rescued by exogenous cavin-1 but not the leucine-zipper motif deleted cavin-1 mutant. Plasma membrane dynamics is an important factor in cell motility control. Our results suggested that the membrane dynamics in cell migration is affected by caveolae associated PTRF/cavin-1.« less

Mm-size bistable zipping dielectric elastomer actuators for integrated microfluidics

NASA Astrophysics Data System (ADS)

Maffli, Luc; Rosset, Samuel; Shea, Herbert R.

2013-04-01

We report on a new structure of Dielectric Elastomer Actuators (DEAs) called zipping DEAs, which have a set of unique characteristics that are a good match for the requirements of electrically-powered integrated microfluidic pumping and/or valving units as well as Braille displays. The zipping DEAs operate by pulling electrostatically an elastomer membrane in contact with the rigid sidewalls of a sloped chamber. In this work, we report on fully functional mm-size zipping DEAs that demonstrate a complete sealing of the chamber sidewalls and a tunable bistable behavior, and compare the measurements with an analytical model. Compared to our first generation of devices, we are able vary the sidewall angle and benefit therefore from more flexibility to study the requirements to make fully functional actuators. In particular, we show that with Nusil CF19 as membrane material (1.2 MPa Young's modulus), it is possible to zip completely 2.3 mm diameter chambers with 15° and 21° sidewalls angle equibiaxially prestretched to λ0=1.12 and 15° chambers with λ0=1.27.

Stages of Huntington's Disease (HD)

MedlinePlus

... HD The Scope of HD Who Is At Risk Genetic Testing & Family Planning Juvenile HD An End to HD? ... hd The Scope of hd Who is at-risk? GENETIC TESTING & FAMILY PLANNING PRENATAL TESTING JHD OVERVIEW AN END ...

What is HD - Huntington's Disease?

MedlinePlus

... HD The Scope of HD Who Is At Risk Genetic Testing & Family Planning Juvenile HD An End to HD? ... hd The Scope of hd Who is at-risk? GENETIC TESTING & FAMILY PLANNING PRENATAL TESTING JHD OVERVIEW AN END ...

Hepatic ZIP14-mediated zinc transport is required for adaptation to endoplasmic reticulum stress

PubMed Central

Kim, Min-Hyun; Aydemir, Tolunay B.; Kim, Jinhee; Cousins, Robert J.

2017-01-01

Extensive endoplasmic reticulum (ER) stress damages the liver, causing apoptosis and steatosis despite the activation of the unfolded protein response (UPR). Restriction of zinc from cells can induce ER stress, indicating that zinc is essential to maintain normal ER function. However, a role for zinc during hepatic ER stress is largely unknown despite important roles in metabolic disorders, including obesity and nonalcoholic liver disease. We have explored a role for the metal transporter ZIP14 during pharmacologically and high-fat diet–induced ER stress using Zip14−/− (KO) mice, which exhibit impaired hepatic zinc uptake. Here, we report that ZIP14-mediated hepatic zinc uptake is critical for adaptation to ER stress, preventing sustained apoptosis and steatosis. Impaired hepatic zinc uptake in Zip14 KO mice during ER stress coincides with greater expression of proapoptotic proteins. ER stress-induced Zip14 KO mice show greater levels of hepatic steatosis due to higher expression of genes involved in de novo fatty acid synthesis, which are suppressed in ER stress-induced WT mice. During ER stress, the UPR-activated transcription factors ATF4 and ATF6α transcriptionally up-regulate Zip14 expression. We propose ZIP14 mediates zinc transport into hepatocytes to inhibit protein-tyrosine phosphatase 1B (PTP1B) activity, which acts to suppress apoptosis and steatosis associated with hepatic ER stress. Zip14 KO mice showed greater hepatic PTP1B activity during ER stress. These results show the importance of zinc trafficking and functional ZIP14 transporter activity for adaptation to ER stress associated with chronic metabolic disorders. PMID:28673968

hZIP1 zinc uptake transporter down regulation and zinc depletion in prostate cancer

PubMed Central

Franklin, Renty B; Feng, Pei; Milon, B; Desouki, Mohamed M; Singh, Keshav K; Kajdacsy-Balla, André; Bagasra, Omar; Costello, Leslie C

2005-01-01

Background The genetic and molecular mechanisms responsible for and associated with the development and progression of prostate malignancy are largely unidentified. The peripheral zone is the major region of the human prostate gland where malignancy develops. The normal peripheral zone glandular epithelium has the unique function of accumulating high levels of zinc. In contrast, the ability to accumulate zinc is lost in the malignant cells. The lost ability of the neoplastic epithelial cells to accumulate zinc is a consistent factor in their development of malignancy. Recent studies identified ZIP1 (SLC39A1) as an important zinc transporter involved in zinc accumulation in prostate cells. Therefore, we investigated the possibility that down-regulation of hZIP1 gene expression might be involved in the inability of malignant prostate cells to accumulate zinc. To address this issue, the expression of hZIP1 and the depletion of zinc in malignant versus non-malignant prostate glands of prostate cancer tissue sections were analyzed. hZIP1 expression was also determined in malignant prostate cell lines. Results hZIP1 gene expression, ZIP1 transporter protein, and cellular zinc were prominent in normal peripheral zone glandular epithelium and in benign hyperplastic glands (also zinc accumulating glands). In contrast, hZIP1 gene expression and transporter protein were markedly down-regulated and zinc was depleted in adenocarcinomatous glands and in prostate intra-epithelial neoplastic foci (PIN). These changes occur early in malignancy and are sustained during its progression in the peripheral zone. hZIP1 is also expressed in the malignant cell lines LNCaP, PC-3, DU-145; and in the nonmalignant cell lines HPr-1 and BPH-1. Conclusion The studies clearly establish that hZIP1 gene expression is down regulated and zinc is depleted in adenocarcinomatous glands. The fact that all the malignant cell lines express hZIP1 indicates that the down-regulation in adenocarcinomatous

Knockdown of Zinc Transporter ZIP5 by RNA Interference Inhibits Esophageal Cancer Growth In Vivo.

PubMed

Li, Qian; Jin, Jing; Liu, Jianghui; Wang, Liqun; He, Yutong

2016-01-01

We recently found that SLC39A5 (ZIP5), a zinc transporter, is overexpressed in esophageal cancer. Downregulation of ZIP5 inhibited the proliferation, migration, and invasion of the esophageal cancer cell line KYSE170 in vitro. In this study, we found that downregulation of SLC39A5 (ZIP5) by interference resulted in a significant reduction in esophageal cancer tumor volume and weight in vivo. COX2 (cyclooxygenase 2) expression was decreased and E-cadherin expression was increased in the KYSE170K xenografts, which was caused by the downregulation of ZIP5. However, we did not find that the downregulation of ZIP5 caused a change in the relative expressions of cyclin D1, VEGF (vascular endothelial growth factor), MMP9 (matrix metalloprotein 9), and Bcl-2 (B-cell lymphoma/leukmia-2) mRNA or an alteration in the average level of zinc in the peripheral blood and xenografts in vivo. Collectively, these findings indicate that knocking down ZIP5 by small interfering RNA (siRNA) might be a novel treatment strategy for esophageal cancer with ZIP5 overexpression.

Knockdown of zinc transporter ZIP8 expression inhibits neuroblastoma progression and metastasis in vitro.

PubMed

Mei, Zhengrong; Yan, Pengke; Wang, Ying; Liu, Shaozhi; He, Fang

2018-05-02

Neuroblastoma is one of the leading causes of cancer‑associated mortality worldwide, particularly in children, partially due to the absence of effective therapeutic targets and diagnostic biomarkers. Therefore, novel molecular targets are critical to the development of therapeutic approaches for neuroblastoma. In the present study, the functions of zinc transporter ZIP8 (Zip8), a member of the zinc transporting protein family, were investigated as novel molecular targets in neuroblastoma cancer cells. The proliferation rates of neuroblastoma cancer cells were significantly decreased when Zip8 was knocked down by lentiviral‑mediated RNA interference. Study of the molecular mechanism suggested that Zip8 modulated the expression of key genes involved in the nuclear factor‑κB signaling pathway. Furthermore, Zip8 depletion suppressed the migratory potential of neuroblastoma cancer cells by reducing the expression levels of matrix metalloproteinases. In conclusion, the results of the present study suggested that Zip8 was an important regulator of neuroblastoma cell proliferation and migration, indicating that Zip8 may be a potential anticancer therapeutic target and a promising diagnostic biomarker for human neuroblastoma.

Modelling of three long-periodic magnetic CP-stars: HD 2453, HD 12288, and HD 200311

NASA Astrophysics Data System (ADS)

Glagolevskij, Yurij V.; Gerth, Ewald

2004-12-01

Using observational data published as phase curves of the effective magnetic field strength Be(P) and the surface field Bs(P), magnetic models of three stars with long rotational periods are calculated by the Magnetic Charge Distribution method. For two of these stars (HD 2453 and HD 12288), the structure of the magnetic field can be described well by a central dipole model. The third star (HD 200311) is better fitted by a model of a displaced dipole, being decentered by triangle r = 0.08 R along the dipole axis.

A kMC-MD method with generalized move-sets for the simulation of folding of α-helical and β-stranded peptides.

PubMed

Peter, Emanuel K; Pivkin, Igor V; Shea, Joan-Emma

2015-04-14

In Monte-Carlo simulations of protein folding, pathways and folding times depend on the appropriate choice of the Monte-Carlo move or process path. We developed a generalized set of process paths for a hybrid kinetic Monte Carlo-Molecular dynamics algorithm, which makes use of a novel constant time-update and allows formation of α-helical and β-stranded secondary structures. We apply our new algorithm to the folding of 3 different proteins: TrpCage, GB1, and TrpZip4. All three systems are seen to fold within the range of the experimental folding times. For the β-hairpins, we observe that loop formation is the rate-determining process followed by collapse and formation of the native core. Cluster analysis of both peptides reveals that GB1 folds with equal likelihood along a zipper or a hydrophobic collapse mechanism, while TrpZip4 follows primarily a zipper pathway. The difference observed in the folding behavior of the two proteins can be attributed to the different arrangements of their hydrophobic core, strongly packed, and dry in case of TrpZip4, and partially hydrated in the case of GB1.

Detection of planet candidates around K giants. HD 40956, HD 111591, and HD 113996

NASA Astrophysics Data System (ADS)

Jeong, G.; Lee, B.-C.; Han, I.; Omiya, M.; Izumiura, H.; Sato, B.; Harakawa, H.; Kambe, E.; Mkrtichian, D.

2018-02-01

Aims: The purpose of this paper is to detect and investigate the nature of long-term radial velocity (RV) variations of K-type giants and to confirm planetary companions around the stars. Methods: We have conducted two planet search programs by precise RV measurement using the 1.8 m telescope at Bohyunsan Optical Astronomy Observatory (BOAO) and the 1.88 m telescope at Okayama Astrophysical Observatory (OAO). The BOAO program searches for planets around 55 early K giants. The OAO program is looking for 190 G-K type giants. Results: In this paper, we report the detection of long-period RV variations of three K giant stars, HD 40956, HD 111591, and HD 113996. We investigated the cause of the observed RV variations and conclude the substellar companions are most likely the cause of the RV variations. The orbital analyses yield P = 578.6 ± 3.3 d, m sin i = 2.7 ± 0.6 MJ, a = 1.4 ± 0.1 AU for HD 40956; P = 1056.4 ± 14.3 d, m sin i = 4.4 ± 0.4 MJ, a = 2.5 ± 0.1 AU for HD 111591; P = 610.2 ± 3.8 d, m sin i = 6.3 ± 1.0 MJ, a = 1.6 ± 0.1 AU for HD 113996. Based on observations made with the BOES at BOAO in Korea and HIDES at OAO in Japan.Tables 3-5 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/610/A3

Stimuli-enabled zipper-like graphene interface for auto-switchable bioelectronics.

PubMed

Mishra, Sachin; Ashaduzzaman, Md; Mishra, Prashant; Swart, Hendrik C; Turner, Anthony P F; Tiwari, Ashutosh

2017-03-15

Graphene interfaces with multi-stimuli responsiveness are of particular interest due to their diverse super-thin interfacial behaviour, which could be well suited to operating complex physiological systems in a single miniaturised domain. In general, smart graphene interfaces switch bioelectrodes from the hydrophobic to hydrophilic state, or vice versa, upon triggering. In the present work, a stimuli encoded zipper-like graphene oxide (GrO)/polymer interface was fabricated with in situ poly(N-isopropylacrylamide-co-diethylaminoethylmethylacrylate), i.e., poly(NIPAAm-co-DEAEMA) directed hierarchical self-assembly of GrO and glucose oxidase (GOx). The designed interface exhibited reversible on/off-switching of bio-electrocatalysis on changing the pH between 5 and 8, via phase transition from super hydrophilic to hydrophobic. The study further indicated that the zipper-like interfacial bioelectrochemical properties could be tuned over a modest change of temperature (i.e., 20-40°C). The resulting auto-switchable interface has implications for the design of novel on/off-switchable biodevices with 'in-built' self-control. Copyright © 2016 Elsevier B.V. All rights reserved.

High-Q silica zipper cavity for optical radiation pressure driven MOMS switch

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

Tetsumoto, Tomohiro; Tanabe, Takasumi, E-mail: takasumi@elec.keio.ac.jp

2014-07-15

We design a silica zipper cavity that has high optical and mechanical Q (quality factor) values and demonstrate numerically the feasibility of a radiation pressure driven micro opto-mechanical system (MOMS) directional switch. The silica zipper cavity has an optical Q of 4.0 × 10{sup 4} and an effective mode volume V{sub mode} of 0.67λ{sup 3} when the gap between two cavities is 34 nm. The mechanical Q (Q{sub m}) is determined by thermo-elastic damping and is 2.0 × 10{sup 6} in a vacuum at room temperature. The opto-mechanical coupling rate g{sub OM} is as high as 100 GHz/nm, which allowsmore » us to move the directional cavity-waveguide system and switch 1550-nm light with 770-nm light by controlling the radiation pressure.« less

A role for the Drosophila zinc transporter Zip88E in protecting against dietary zinc toxicity.

PubMed

Richards, Christopher D; Warr, Coral G; Burke, Richard

2017-01-01

Zinc absorption in animals is thought to be regulated in a local, cell autonomous manner with intestinal cells responding to dietary zinc content. The Drosophila zinc transporter Zip88E shows strong sequence similarity to Zips 42C.1, 42C.2 and 89B as well as mammalian Zips 1, 2 and 3, suggesting that it may act in concert with the apically-localised Drosophila zinc uptake transporters to facilitate dietary zinc absorption by importing ions into the midgut enterocytes. However, the functional characterisation of Zip88E presented here indicates that Zip88E may instead play a role in detecting and responding to zinc toxicity. Larvae homozygous for a null Zip88E allele are viable yet display heightened sensitivity to elevated levels of dietary zinc. This decreased zinc tolerance is accompanied by an overall decrease in Metallothionein B transcription throughout the larval midgut. A Zip88E reporter gene is expressed only in the salivary glands, a handful of enteroendocrine cells at the boundary between the anterior and middle midgut regions, and in two parallel strips of sensory cell projections connecting to the larval ventral ganglion. Zip88E expression solely in this restricted subset of cells is sufficient to rescue the Zip88E mutant phenotype. Together, our data suggest that Zip88E may be functioning in a small subset of cells to detect excessive zinc levels and induce a systemic response to reduce dietary zinc absorption and hence protect against toxicity.

Detection of accreting gas toward HD 45677: A newly recognized, Herbig Be proto-planetary system

NASA Technical Reports Server (NTRS)

Grady, C. A.; Bjorkman, K. S.; Shepherd, D.; Schulte-Ladbeck, R. E.; Perez, M. R.; Dewinter, D.; The, P. S.

1993-01-01

We report detection of high velocity, accreting gas toward the Be star with IR excess and bipolar nebula, HD 45677. High velocity (+200 to +400 km/s), variable column density gas is visible in all IUE spectra from 1979-1992 in transitions of Si II, C II, Al III, Fe III, Si IV, and C IV. Low-velocity absorption profiles from low oscillator-strength transitions of Si II, Fe II, and Zn II exhibit double-peaked absorption profiles similar to those previously reported in optical spectra of FU Orionis objects. The UV absorption data, together with previously reported analyses of the IR excess and polarization of this object, suggest that HD 45677 is a massive, Herbig Be star with an actively accreting circumstellar, proto-planetary disk.

The nature of the late B-type stars HD 67044 and HD 42035

NASA Astrophysics Data System (ADS)

Monier, R.; Gebran, M.; Royer, F.

2016-04-01

While monitoring a sample of apparently slowly rotating superficially normal bright late B and early A stars in the northern hemisphere, we have discovered that HD 67044 and HD 42035, hitherto classified as normal late B-type stars, are actually respectively a new chemically peculiar star and a new spectroscopic binary containing a very slow rotator HD 42035 S with ultra-sharp lines (v_{{e}}sin i= 3.7 km s^{-1}) and a fast rotator HD 42035 B with broad lines. The lines of Ti ii, Cr ii, Mn ii, Sr ii, Y ii, Zr ii and Ba ii are conspicuous features in the high resolution SOPHIE spectrum (R=75000) of HD 67044. The Hg ii line at 3983.93 Å is also present as a weak feature. The composite spectrum of HD 42035 is characterised by very sharp lines formed in HD 42035 S superimposed onto the shallow and broad lines of HD 42035 B. These very sharp lines are mostly due to light elements from C to Ni, the only heavy species definitely present are strontium and barium. Selected lines of 21 chemical elements from He up to Hg have been synthesized using model atmospheres computed with ATLAS9 and the spectrum synthesis code SYNSPEC48 including hyperfine structure of various isotopes when relevant. These synthetic spectra have been adjusted to high resolution high signal-to-noise spectra of HD 67044 and HD 42035 S in order to derive abundances of these key elements. HD 67044 is found to have distinct enhancements of Ti, Cr, Mn, Sr, Y, Zr, Ba and Hg and underabundances in He, C, O, Ca and Sc which shows that this star is not a superficially normal late B-type star, but actually is a new CP star most likely of the HgMn type. HD 42035 S has provisional underabundances of the light elements from C to Ti and overabundances of heavier elements (except for Fe and Sr which are also underabundant) up to barium. These values are lower limits to the actual abundances as we cannot currently place properly the continuum of HD 42035 S. More accurate fundamental parameters and abundances for HD

A specific role for the ZipA protein in cell division: stabilization of the FtsZ protein.

PubMed

Pazos, Manuel; Natale, Paolo; Vicente, Miguel

2013-02-01

In Escherichia coli, the cell division protein FtsZ is anchored to the cytoplasmic membrane by the action of the bitopic membrane protein ZipA and the cytoplasmic protein FtsA. Although the presence of both ZipA and FtsA is strictly indispensable for cell division, an FtsA gain-of-function mutant FtsA* (R286W) can bypass the ZipA requirement for cell division. This observation casts doubts on the role of ZipA and its need for cell division. Maxicells are nucleoid-free bacterial cells used as a whole cell in vitro system to probe protein-protein interactions without the need of protein purification. We show that ZipA protects FtsZ from the ClpXP-directed degradation observed in E. coli maxicells and that ZipA-stabilized FtsZ forms membrane-attached spiral-like structures in the bacterial cytoplasm. The overproduction of the FtsZ-binding ZipA domain is sufficient to protect FtsZ from degradation, whereas other C-terminal ZipA partial deletions lacking it are not. Individual overproduction of the proto-ring component FtsA or its gain-of-function mutant FtsA* does not result in FtsZ protection. Overproduction of FtsA or FtsA* together with ZipA does not interfere with the FtsZ protection. Moreover, neither FtsA nor FtsA* protects FtsZ when overproduced together with ZipA mutants lacking the FZB domain. We propose that ZipA protects FtsZ from degradation by ClpP by making the FtsZ site of interaction unavailable to the ClpX moiety of the ClpXP protease. This role cannot be replaced by either FtsA or FtsA*, suggesting a unique function for ZipA in proto-ring stability.

Poplar PtabZIP1-like enhances lateral root formation and biomass growth under drought stress

DOE PAGES

Dash, Madhumita; Yordanov, Yordan S.; Georgieva, Tatyana; ...

2017-02-10

Developing drought-resistance varieties is a major goal for bioenergy crops, such as poplar (Populus), which will be grown on marginal lands with little or no water input. Root architecture can affect drought resistance, but few genes that affect root architecture in relation to water availability have been identified. Here in this study, using activation tagging in the prime bioenergy crop poplar, we have identified a mutant that overcomes the block of lateral root (LR) formation under osmotic stress. Positioning of the tag, validation of the activation and recapitulation showed that the phenotype is caused by the poplar PtabZIP1-like (PtabZIP1L) genemore » with highest homology to bZIP1 from Arabidopsis. PtabZIP1L is predominantly expressed in roots, particularly in zones where lateral root primordia (LRP) initiate and LR differentiate and emerge. Transgenics overexpressing PtabZIP1L showed precocious LRP and LR development, while PtabZIP1L suppression significantly delayed both LRP and LR formation. Transgenic overexpression and suppression of PtabZIP1L also resulted in modulation of key metabolites like proline, asparagine, valine and several flavonoids. Consistently, expression of both of the poplar Proline Dehydrogenase orthologs and two of the Flavonol Synthases genes was also increased and decreased in overexpressed and suppressed transgenics, respectively. These findings suggest that PtabZIP1L mediates LR development and drought resistance through modulation of multiple metabolic pathways.« less

Poplar PtabZIP1-like enhances lateral root formation and biomass growth under drought stress

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

Dash, Madhumita; Yordanov, Yordan S.; Georgieva, Tatyana

Developing drought-resistance varieties is a major goal for bioenergy crops, such as poplar (Populus), which will be grown on marginal lands with little or no water input. Root architecture can affect drought resistance, but few genes that affect root architecture in relation to water availability have been identified. Here in this study, using activation tagging in the prime bioenergy crop poplar, we have identified a mutant that overcomes the block of lateral root (LR) formation under osmotic stress. Positioning of the tag, validation of the activation and recapitulation showed that the phenotype is caused by the poplar PtabZIP1-like (PtabZIP1L) genemore » with highest homology to bZIP1 from Arabidopsis. PtabZIP1L is predominantly expressed in roots, particularly in zones where lateral root primordia (LRP) initiate and LR differentiate and emerge. Transgenics overexpressing PtabZIP1L showed precocious LRP and LR development, while PtabZIP1L suppression significantly delayed both LRP and LR formation. Transgenic overexpression and suppression of PtabZIP1L also resulted in modulation of key metabolites like proline, asparagine, valine and several flavonoids. Consistently, expression of both of the poplar Proline Dehydrogenase orthologs and two of the Flavonol Synthases genes was also increased and decreased in overexpressed and suppressed transgenics, respectively. These findings suggest that PtabZIP1L mediates LR development and drought resistance through modulation of multiple metabolic pathways.« less

Crystal structure of a super leucine zipper, an extended two-stranded super long coiled coil

PubMed Central

Diao, Jiasheng

2010-01-01

Coiled coil is a ubiquitous structural motif in proteins, with two to seven alpha helices coiled together like the strands of a rope, and coiled coil folding and assembly is not completely understood. A GCN4 leucine zipper mutant with four mutations of K3A, D7A, Y17W, and H18N has been designed, and the crystal structure has been determined at 1.6 Å resolution. The peptide monomer shows a helix trunk with short curved N- and C-termini. In the crystal, two monomers cross in 35° and form an X-shaped dimer, and each X-shaped dimer is welded into the next one through sticky hydrophobic ends, thus forming an extended two-stranded, parallel, super long coiled coil rather than a discrete, two-helix coiled coil of the wild-type GCN4 leucine zipper. Leucine residues appear at every seventh position in the super long coiled coil, suggesting that it is an extended super leucine zipper. Compared to the wild-type leucine zipper, the N-terminus of the mutant has a dramatic conformational change and the C-terminus has one more residue Glu 32 determined. The mutant X-shaped dimer has a large crossing angle of 35° instead of 18° in the wild-type dimer. The results show a novel assembly mode and oligomeric state of coiled coil, and demonstrate that mutations may affect folding and assembly of the overall coiled coil. Analysis of the formation mechanism of the super long coiled coil may help understand and design self-assembling protein fibers. PMID:20027625

Crystal Structure of a Super Leucine Zipper an Extended Two-Stranded Super Long Coiled Coil

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

J Diao

2011-12-31

Coiled coil is a ubiquitous structural motif in proteins, with two to seven alpha helices coiled together like the strands of a rope, and coiled coil folding and assembly is not completely understood. A GCN4 leucine zipper mutant with four mutations of K3A, D7A, Y17W, and H18N has been designed, and the crystal structure has been determined at 1.6 {angstrom} resolution. The peptide monomer shows a helix trunk with short curved N- and C-termini. In the crystal, two monomers cross in 35{sup o} and form an X-shaped dimer, and each X-shaped dimer is welded into the next one through stickymore » hydrophobic ends, thus forming an extended two-stranded, parallel, super long coiled coil rather than a discrete, two-helix coiled coil of the wild-type GCN4 leucine zipper. Leucine residues appear at every seventh position in the super long coiled coil, suggesting that it is an extended super leucine zipper. Compared to the wild-type leucine zipper, the N-terminus of the mutant has a dramatic conformational change and the C-terminus has one more residue Glu 32 determined. The mutant X-shaped dimer has a large crossing angle of 35{sup o} instead of 18{sup o} in the wild-type dimer. The results show a novel assembly mode and oligomeric state of coiled coil, and demonstrate that mutations may affect folding and assembly of the overall coiled coil. Analysis of the formation mechanism of the super long coiled coil may help understand and design self-assembling protein fibers.« less

DNA hybridization kinetics: zippering, internal displacement and sequence dependence.

PubMed

Ouldridge, Thomas E; Sulc, Petr; Romano, Flavio; Doye, Jonathan P K; Louis, Ard A

2013-10-01

Although the thermodynamics of DNA hybridization is generally well established, the kinetics of this classic transition is less well understood. Providing such understanding has new urgency because DNA nanotechnology often depends critically on binding rates. Here, we explore DNA oligomer hybridization kinetics using a coarse-grained model. Strand association proceeds through a complex set of intermediate states, with successful binding events initiated by a few metastable base-pairing interactions, followed by zippering of the remaining bonds. But despite reasonably strong interstrand interactions, initial contacts frequently dissociate because typical configurations in which they form differ from typical states of similar enthalpy in the double-stranded equilibrium ensemble. Initial contacts must be stabilized by two or three base pairs before full zippering is likely, resulting in negative effective activation enthalpies. Non-Arrhenius behavior arises because the number of base pairs required for nucleation increases with temperature. In addition, we observe two alternative pathways-pseudoknot and inchworm internal displacement-through which misaligned duplexes can rearrange to form duplexes. These pathways accelerate hybridization. Our results explain why experimentally observed association rates of GC-rich oligomers are higher than rates of AT- rich equivalents, and more generally demonstrate how association rates can be modulated by sequence choice.

Comparisons of amino acids, body constituents and antioxidative response between long-time HD and normal HD.

PubMed

Torigoe, Akira; Sato, Emiko; Mori, Takefumi; Ieiri, Norio; Takahashi, Chika; Ishida, Yoko; Hotta, Osamu; Ito, Sadayoshi

2016-10-01

Introduction Oxidative stress is one of the main mediators of progression of chronic kidney diseases (CKD). Nuclear factor E2-related factor 2 (Nrf2) is the transcription factor of antioxidant and detoxifying enzymes and related proteins which play an important role in cellular defense. Long-time hemodialysis (HD) therapy (8 hours) has been considered to be more beneficial compared to normal HD therapy (4 hours). We investigated oxidative response related to Nrf2 in peripheral blood mononuclear cells (PBMCs) of long-time HD and normal HD patients. Methods Eight adult long-time HD therapy patients (44.5 ± 3.0 years) and 10 normal HD therapy patients (68.1 ± 2.7 years) were enrolled. PBMCs were isolated and processed for expression of Nrf2 and its related genes by qRT-PCR. Plasma indoxyl sulfate, amino acids, and body constituents were measured. Findings Plasma indoxyl sulfate was significantly low after long-time HD therapy compare to that of normal HD therapy. Although, skeletal muscle mass, lean body mass, mineral and protein were significantly decreased 2 months in normal HD patients, those in long-time HD patients were significantly increased after 2 months. Almost of amino acids were significantly decreased after HD therapy in both HD therapies. Plasma amino acids were significantly low in long-time HD patients compared to normal HD patients. In PBMCs, the expression of Nrf2 was significantly decreased and hemooxygenase-1 expression was significantly increased in long-time HD compared to normal HD. Conclusion These observations indicate the beneficial effects of in long-time HD in improving oxidative stress in patients. © 2016 International Society for Hemodialysis.

Pointwise regularity of parameterized affine zipper fractal curves

NASA Astrophysics Data System (ADS)

Bárány, Balázs; Kiss, Gergely; Kolossváry, István

2018-05-01

We study the pointwise regularity of zipper fractal curves generated by affine mappings. Under the assumption of dominated splitting of index-1, we calculate the Hausdorff dimension of the level sets of the pointwise Hölder exponent for a subinterval of the spectrum. We give an equivalent characterization for the existence of regular pointwise Hölder exponent for Lebesgue almost every point. In this case, we extend the multifractal analysis to the full spectrum. In particular, we apply our results for de Rham’s curve.

Production and Testing of Transgenic Cotton that Expresses Transcription Factors for Enhanced Seed and Fiber Traits and Productivity Under Drought Stress

USDA-ARS?s Scientific Manuscript database

Abscisic acid (ABA) is a plant hormone involved in abiotic and biotic stress adaptation and seed development. We have previously shown that Basic3 (B3) domain and basic leucine zipper (b-ZIP) transcription factors from the model plant species maize and Arabidopsis thaliana can transactivate monocot...

Early memory formation disrupted by atypical PKC inhibitor ZIP in the medial prefrontal cortex but not hippocampus

PubMed Central

Evuarherhe, Obaro; Barker, Gareth R. I.; Savalli, Giorgia; Warburton, Elizabeth C.; Brown, Malcolm W.

2014-01-01

Atypical isoforms of protein kinase C (aPKCs; particularly protein kinase M zeta: PKMζ) have been hypothesised to be necessary and sufficient for the maintenance of long-term potentiation (LTP) and long term memory by maintaining postsynaptic AMPA receptors via the GluR2 subunit. A myristoylated PKMζ pseudosubstrate peptide (ZIP) blocks PKMζ activity. We examined the actions of ZIP in medial prefrontal cortex (mPFC) and hippocampus in associative recognition memory in rats during early memory formation and memory maintenance. ZIP infusion in either hippocampus or mPFC impaired memory maintenance. However, early memory formation was impaired by ZIP in mPFC but not hippocampus; and blocking GluR2-dependent removal of AMPA receptors did not affect this impairment caused by ZIP in the mPFC. The findings indicate: (i) a difference in the actions of ZIP in hippocampus and medial prefrontal cortex, and (ii) a GluR2-independent target of ZIP (possibly PKCλ) in the mPFC during early memory formation. PMID:24729442

Shadows and cavities in protoplanetary disks: HD 163296, HD 141569A, and HD 150193A in polarized light

NASA Astrophysics Data System (ADS)

Garufi, A.; Quanz, S. P.; Schmid, H. M.; Avenhaus, H.; Buenzli, E.; Wolf, S.

2014-08-01

Context. The morphological evolution of dusty disks around young (a few Myr old) stars is pivotal for a better understanding of planet formation. Since both dust grains and the global disk geometry evolve on short timescales, high-resolution imaging of a sample of objects may provide important indications about this evolution. Aims: We enlarge the sample of protoplanetary disks imaged in polarized light with high-resolution imaging (≲0.2″) by observing the Herbig Ae/Be stars HD 163296, HD 141569A, and HD 150193A. We combine our data with previous datasets to understand the larger context of their morphology. Methods: Polarimetric differential imaging is an attractive technique with which to image at near-IR wavelengths a significant fraction of the light scattered by the circumstellar material. The unpolarized stellar light is canceled out by combining two simultaneous orthogonal polarization states. This allowed us to achieve an inner working angle and an angular resolution as low as ~0.1″. Results: We report a weak detection of the disk around HD 163296 in the H and KS bands. The disk is resolved as a broken ring structure with a significant surface brightness drop inward of 0.6″. No sign of extended polarized emission is detected from the disk around HD 141569A and HD 150193A. Conclusions: We propose that the absence of scattered light in the inner 0.6″ around HD 163296 and the non-detection of the disk around HD 150193A may be due to similar geometric factors. Since these disks are known to be flat or only moderately flared, self-shadowing by the disk inner wall is the favored explanation. We show that the polarized brightness of a number of disks is indeed related to their flaring angle. Other scenarios (such as dust grain growth or interaction with icy molecules) are also discussed. On the other hand, the non-detection of HD 141569A is consistent with previous datasets that revealed a huge cavity in the dusty disk. Based on observations collected at

An active Mitochondrial Complex II Present in Mature Seeds Contains an Embryo-Specific Iron-Sulfur Subunit Regulated by ABA and bZIP53 and Is Involved in Germination and Seedling Establishment.

PubMed

Restovic, Franko; Espinoza-Corral, Roberto; Gómez, Isabel; Vicente-Carbajosa, Jesús; Jordana, Xavier

2017-01-01

Complex II (succinate dehydrogenase) is an essential mitochondrial enzyme involved in both the tricarboxylic acid cycle and the respiratory chain. In Arabidopsis thaliana , its iron-sulfur subunit (SDH2) is encoded by three genes, one of them ( SDH2.3 ) being specifically expressed during seed maturation in the embryo. Here we show that seed SDH2.3 expression is regulated by abscisic acid (ABA) and we define the promoter region (-114 to +49) possessing all the cis -elements necessary and sufficient for high expression in seeds. This region includes between -114 and -32 three ABRE (ABA-responsive) elements and one RY-enhancer like element, and we demonstrate that these elements, although necessary, are not sufficient for seed expression, our results supporting a role for the region encoding the 5' untranslated region (+1 to +49). The SDH2.3 promoter is activated in leaf protoplasts by heterodimers between the basic leucine zipper transcription factors bZIP53 (group S1) and bZIP10 (group C) acting through the ABRE elements, and by the B3 domain transcription factor ABA insensitive 3 (ABI3). The in vivo role of bZIP53 is further supported by decreased SDH2.3 expression in a knockdown bzip53 mutant. By using the protein synthesis inhibitor cycloheximide and sdh2 mutants we have been able to conclusively show that complex II is already present in mature embryos before imbibition, and contains mainly SDH2.3 as iron-sulfur subunit. This complex plays a role during seed germination sensu-stricto since we have previously shown that seeds lacking SDH2.3 show retarded germination and now we demonstrate that low concentrations of thenoyltrifluoroacetone, a complex II inhibitor, also delay germination. Furthermore, complex II inhibitors completely block hypocotyl elongation in the dark and seedling establishment in the light, highlighting an essential role of complex II in the acquisition of photosynthetic competence and the transition from heterotrophy to autotrophy.

Tumor Heterogeneity of FIGO Stage III Carcinoma of the Uterine Cervix

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

Kim, Yong Bae; Lee, Ik Jae; Kim, Song Yih

2009-12-01

Purpose: The purpose of this study was to analyze tumor heterogeneity based on tumor extent and suggest reappraisal of the system of the International Federation of Gynecology and Obstetrics (FIGO) for Stage III carcinoma of the uterine cervix from a radiotherapeutic viewpoint. Methods and Materials: Between 1986 and 2004, 407 patients with FIGO Stage III (FIGO Stage IIIa in 19 and IIIb in 388) were treated with external beam radiotherapy (RT) and high-dose rate brachytherapy. All patients were reviewed with respect to tumor extent. Patterns of failure and survival parameters were analyzed by use of the chi{sup 2} test andmore » Kaplan-Meier method. Results: The complete response rate was 79.6%, and the 5-year overall survival rates for Stage IIIa and Stage IIIb carcinoma of the cervix were 82.1% and 54.8%, respectively. To determine which parameters of tumor extent had an influence on prognosis for Stage IIIb patients, pelvic wall (PW) extension and hydronephrosis (HD) retained significance on multivariate analysis. Stage IIIb patients were divided into three subgroups according to PW extension and HD: low risk (unilateral PW extension without HD), intermediate risk (HD without PW extension or bilateral PW extension without HD), and high risk (unilateral or bilateral PW extension with HD). The high-risk group had a remarkably low complete response rate, high locoregional failure rate, and low 5-year survival rate compared with the intermediate- and low-risk groups. Conclusions: FIGO Stage III carcinoma of the cervix covers considerably heterogeneous subgroups according to tumor extent. Before initiation of treatment, we suggest that physicians determine a tailored treatment policy based on tumor heterogeneity for each Stage III patient.« less

Characterization of zinc transport by divalent metal transporters of the ZIP family from the model legume medicago truncatula

USDA-ARS?s Scientific Manuscript database

To understand how plants from the Fabaceae family maintain zinc (Zn) homeostasis, we have characterized the kinetics of the Zn transporting proteins from the ZIP family of divalent metal transporters in the model legume Medicago truncatula. MtZIP1, MtZIP5, and MtZIP6 were the only members from this ...

3D Printing of Protein Models in an Undergraduate Laboratory: Leucine Zippers

ERIC Educational Resources Information Center

Meyer, Scott C.

2015-01-01

An upper-division undergraduate laboratory experiment is described that explores the structure/function relationship of protein domains, namely leucine zippers, through a molecular graphics computer program and physical models fabricated by 3D printing. By generating solvent accessible surfaces and color-coding hydrophobic, basic, and acidic amino…

Zinc Transporter SLC39A7/ZIP7 Promotes Intestinal Epithelial Self-Renewal by Resolving ER Stress

PubMed Central

Ohashi, Wakana; Kimura, Shunsuke; Iwanaga, Toshihiko; Furusawa, Yukihiro; Irié, Tarou; Izumi, Hironori; Watanabe, Takashi; Hara, Takafumi; Ohara, Osamu; Koseki, Haruhiko; Sato, Toshiro; Robine, Sylvie; Mori, Hisashi; Hattori, Yuichi; Mishima, Kenji; Ohno, Hiroshi; Hase, Koji; Fukada, Toshiyuki

2016-01-01

Zinc transporters play a critical role in spatiotemporal regulation of zinc homeostasis. Although disruption of zinc homeostasis has been implicated in disorders such as intestinal inflammation and aberrant epithelial morphology, it is largely unknown which zinc transporters are responsible for the intestinal epithelial homeostasis. Here, we show that Zrt-Irt-like protein (ZIP) transporter ZIP7, which is highly expressed in the intestinal crypt, is essential for intestinal epithelial proliferation. Mice lacking Zip7 in intestinal epithelium triggered endoplasmic reticulum (ER) stress in proliferative progenitor cells, leading to significant cell death of progenitor cells. Zip7 deficiency led to the loss of Olfm4+ intestinal stem cells and the degeneration of post-mitotic Paneth cells, indicating a fundamental requirement for Zip7 in homeostatic intestinal regeneration. Taken together, these findings provide evidence for the importance of ZIP7 in maintenance of intestinal epithelial homeostasis through the regulation of ER function in proliferative progenitor cells and maintenance of intestinal stem cells. Therapeutic targeting of ZIP7 could lead to effective treatment of gastrointestinal disorders. PMID:27736879

A modified detector concept for SuperCDMS: The HiZIP and its charge performance

NASA Astrophysics Data System (ADS)

Page, Kedar Mohan

SuperCDMS is a leading direct dark matter search experiment which uses solid state detectors (Ge crystals) at milliKelvin temperatures to look for nuclear recoils caused by dark matter interactions in the detector. 'Weakly Interacting Massive Particles' (WIMPs) are the most favoured dark matter candidate particles. SuperCDMS, like many other direct dark matter search experiments, primarily looks for WIMPs. The measurement of both the ionization and the lattice vibration (phonon) signals from an interaction in the detector allow it to discriminate against electron recoils which are the main source of background for WIMP detection. SuperCDMS currently operates about 9 kgs worth of germanium detectors at the Soudan underground lab in northern Minnesota. In its next phase, SuperCDMS SNOLAB, it plans to use 100-200 kg of target mass (Ge) which would allow it to probe more of the interesting and unexplored parameter space for WIMPs predicted by theoretical models. The SuperCDMS Queen's Test Facility is a detector testing facility which is intended to serve detector testing and detector research and development purposes for the SuperCDMS experiment. A modified detector called the 'HiZIP' (Half-iZIP), which is reduced in complexity in comparison to the currently used iZIP (interleaved Z-sensitive Ionization and Phonon mediated) detectors, is studied in this thesis. The HiZIP detector design also serves to discriminate against background from multiple scatter events occurring close to the surfaces in a single detector. Studies carried out to compare the surface event leakage in the HiZIP detector using limited information from iZIP data taken at SuperCDMS test facility at UC Berkley produce a highly conservative upper limit of 5 out of 10,000 events at 90% confidence level. This upper limit is the best among many different HiZIP configurations that were investigated and is comparable to the upper limit calculated for an iZIP detector in the same way using the same data. A

Services provided by community pharmacies in Wayne County, Michigan: a comparison by ZIP code characteristics.

PubMed

Erickson, Steven R; Workman, Paul

2014-01-01

To document the availability of selected pharmacy services and out-of-pocket cost of medication throughout a diverse county in Michigan and to assess possible associations between availability of services and price of medication and characteristics of residents of the ZIP codes in which the pharmacies were located. Cross-sectional telephone survey of pharmacies coupled with ZIP code-level census data. 503 pharmacies throughout the 63 ZIP codes of Wayne County, MI. The out-of-pocket cost for a 30 days' supply of levothyroxine 50 mcg and brand-name atorvastatin (Lipitor-Pfizer) 20 mg, availability of discount generic drug programs, home delivery of medications, hours of pharmacy operation, and availability of pharmacy-based immunization services. Census data aggregated at the ZIP code level included race, annual household income, age, and number of residents per pharmacy. The overall results per ZIP code showed that the average cost for levothyroxine was $10.01 ± $2.29 and $140.45 + $14.70 for Lipitor. Per ZIP code, the mean (± SD) percentages of pharmacies offering discount generic drug programs was 66.9% ± 15.0%; home delivery of medications was 44.5% ± 22.7%; and immunization for influenza was 46.7% ± 24.3% of pharmacies. The mean (± SD) hours of operation per pharmacy per ZIP code was 67.0 ± 25.2. ZIP codes with higher household income as well as higher percentage of residents being white had lower levothyroxine price, greater percentage of pharmacies offering discount generic drug programs, more hours of operation per week, and more pharmacy-based immunization services. The cost of Lipitor was not associated with any ZIP code characteristic. Disparities in the cost of generic levothyroxine, the availability of services such as discount generic drug programs, hours of operation, and pharmacy-based immunization services are evident based on race and household income within this diverse metropolitan county.

New Precision Orbits of Bright Double-Lined Spectroscopic Binaries. III. HD 82191, ω Draconis, and 108 Herculis

NASA Astrophysics Data System (ADS)

Fekel, Francis C.; Tomkin, Jocelyn; Williamson, Michael H.

2009-04-01

We have determined improved spectroscopic orbits for three double-lined binaries, HD 82191 (Am), ω Dra (F5 V), and 108 Her (Am), using radial velocities from the 2.1 m telescope at McDonald Observatory, the coudé feed telescope at Kitt Peak National Observatory, and 2 m telescope at Fairborn Observatory. The orbital periods range from 5.28 to 9.01 days, and all three systems have circular orbits. The new orbital dimensions (a 1 sin i and a 2 sin i) and minimum masses (m 1 sin3 i and m 2 sin3 i) have accuracies of 0.2% or better. Our improved results confirm the large minimum masses of HD 82191 and also agree with the values previously found for ω Dra. However, for the components of 108 Her our minimum masses are about 20% larger than the previous best values. We conclude that both components of HD 82191 as well as the primary of 108 Her are Am stars. However, the A9 secondary of 108 Her has normal abundances. We estimate spectral types of F4 dwarf and G0 dwarf for the components of ω Dra. The primaries of the three binaries are synchronously rotating as is the secondary of 108 Her. The secondaries of HD 82191 and ω Dra are possibly synchronously rotating.

HD-SAO-DM cross index

NASA Technical Reports Server (NTRS)

Nagy, T. A.; Mead, J.

1978-01-01

A table of correspondence SAO-HD-DM-GC was prepared by Morin (1973). The machine-readable version of this cross identification was obtained from the Centre de Donnees Stellaires (Strasbourg, France). The table was sorted at the Goddard Space Flight Center by HD number and all blank HD number records were removed to produce the HD-SAO-DM table presented. There were 258997 entries in the original table; there are 180411 entries after removing the blank HD records. The Boss General Catalogue (GC) numbers were retained on the machine-readable version after the sort.

A Novel DNA Binding Mechanism for maf Basic Region-Leucine Zipper Factors Inferred from a MafA-DNA Complex Structure and Binding Specificities

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

Lu, Xun; Guanga, Gerald P; Wan, Cheng

2012-11-13

MafA is a proto-oncoprotein and is critical for insulin gene expression in pancreatic β-cells. Maf proteins belong to the AP1 superfamily of basic region-leucine zipper (bZIP) transcription factors. Residues in the basic helix and an ancillary N-terminal domain, the Extended Homology Region (EHR), endow maf proteins with unique DNA binding properties: binding a 13 bp consensus site consisting of a core AP1 site (TGACTCA) flanked by TGC sequences and binding DNA stably as monomers. To further characterize maf DNA binding, we determined the structure of a MafA–DNA complex. MafA forms base-specific hydrogen bonds with the flanking G –5C –4 andmore » central C 0/G 0 bases, but not with the core-TGA bases. However, in vitro binding studies utilizing a pulse–chase electrophoretic mobility shift assay protocol revealed that mutating either the core-TGA or flanking-TGC bases dramatically increases the binding off rate. Comparing the known maf structures, we propose that DNA binding specificity results from positioning the basic helix through unique phosphate contacts. The EHR does not contact DNA directly but stabilizes DNA binding by contacting the basic helix. Collectively, these results suggest a novel multistep DNA binding process involving a conformational change from contacting the core-TGA to contacting the flanking-TGC bases.« less

Genome Wide Identification of Orthologous ZIP Genes Associated with Zinc and Iron Translocation in Setaria italica.

PubMed

Alagarasan, Ganesh; Dubey, Mahima; Aswathy, Kumar S; Chandel, Girish

2017-01-01

Genes in the ZIP family encode transcripts to store and transport bivalent metal micronutrient, particularly iron (Fe) and or zinc (Zn). These transcripts are important for a variety of functions involved in the developmental and physiological processes in many plant species, including most, if not all, Poaceae plant species and the model species Arabidopsis. Here, we present the report of a genome wide investigation of orthologous ZIP genes in Setaria italica and the identification of 7 single copy genes. RT-PCR shows 4 of them could be used to increase the bio-availability of zinc and iron content in grains. Of 36 ZIP members, 25 genes have traces of signal peptide based sub-cellular localization, as compared to those of plant species studied previously, yet translocation of ions remains unclear. In silico analysis of gene structure and protein nature suggests that these two were preeminent in shaping the functional diversity of the ZIP gene family in S. italica . NAC, bZIP and bHLH are the predominant Fe and Zn responsive transcription factors present in SiZIP genes. Together, our results provide new insights into the signal peptide based/independent iron and zinc translocation in the plant system and allowed identification of ZIP genes that may be involved in the zinc and iron absorption from the soil, and thus transporting it to the cereal grain underlying high micronutrient accumulation.

Characterization of depression in prodromal Huntington disease in the neurobiological predictors of HD (PREDICT-HD) study.

PubMed

Epping, Eric A; Mills, James A; Beglinger, Leigh J; Fiedorowicz, Jess G; Craufurd, David; Smith, Megan M; Groves, Mark; Bijanki, Kelly R; Downing, Nancy; Williams, Janet K; Long, Jeffrey D; Paulsen, Jane S

2013-10-01

Depression causes significant morbidity and mortality, and this also occurs in Huntington Disease (HD), an inherited neurodegenerative illness with motor, cognitive, and psychiatric symptoms. The presentation of depression in this population remains poorly understood, particularly in the prodromal period before development of significant motor symptoms. In this study, we assessed depressive symptoms in a sample of 803 individuals with the HD mutation in the prodromal stage and 223 mutation-negative participants at the time of entry in the Neurobiological Predictors of HD (PREDICT-HD) study. Clinical and biological HD variables potentially related to severity of depression were analyzed. A factor analysis was conducted to characterize the symptom domains of depression in a subset (n=168) with clinically significant depressive symptoms. Depressive symptoms were found to be more prevalent in HD mutation carriers but did not increase with proximity to HD diagnosis and were not associated with length of the HD mutation. Increased depressive symptoms were significantly associated with female gender, self-report of past history of depression, and a slight decrease in functioning, but not with time since genetic testing. The factor analysis identified symptom domains similar to prior studies in other populations. These results show that individuals with the HD mutation are at increased risk to develop depressive symptoms at any time during the HD prodrome. The clinical presentation appears to be similar to other populations. Severity and progression are not related to the HD mutation. Copyright © 2013 Elsevier Ltd. All rights reserved.

Homez, a homeobox leucine zipper gene specific to the vertebrate lineage.

PubMed

Bayarsaihan, Dashzeveg; Enkhmandakh, Badam; Makeyev, Aleksandr; Greally, John M; Leckman, James F; Ruddle, Frank H

2003-09-02

This work describes a vertebrate homeobox gene, designated Homez (homeodomain leucine zipper-encoding gene), that encodes a protein with an unusual structural organization. There are several regions within Homez, including three atypical homeodomains, two leucine zipper-like motifs, and an acidic domain. The gene is ubiquitously expressed in human and murine tissues, although the expression pattern is more restricted during mouse development. Genomic analysis revealed that human and mouse genes are located at 14q11.2 and 14C, respectively, and are composed of two exons. The zebrafish and pufferfish homologs share high similarity to mammalian sequences, particularly within the homeodomain sequences. Based on homology of homeodomains and on the similarity in overall protein structure, we delineate Homez and members of ZHX family of zinc finger homeodomain factors as a subset within the superfamily of homeobox-containing proteins. The type and composition of homeodomains in the Homez subfamily are vertebrate-specific. Phylogenetic analysis indicates that Homez lineage was separated from related genes >400 million years ago before separation of ray- and lobe-finned fishes. We apply a duplication-degeneration-complementation model to explain how this family of genes has evolved.

Arabidopsis basic leucine zipper transcription factors involved in an abscisic acid-dependent signal transduction pathway under drought and high-salinity conditions

PubMed Central

Uno, Yuichi; Furihata, Takashi; Abe, Hiroshi; Yoshida, Riichiro; Shinozaki, Kazuo; Yamaguchi-Shinozaki, Kazuko

2000-01-01

The induction of the dehydration-responsive Arabidopsis gene, rd29B, is mediated mainly by abscisic acid (ABA). Promoter analysis of rd29B indicated that two ABA-responsive elements (ABREs) are required for the dehydration-responsive expression of rd29B as cis-acting elements. Three cDNAs encoding basic leucine zipper (bZIP)-type ABRE-binding proteins were isolated by using the yeast one-hybrid system and were designated AREB1, AREB2, and AREB3 (ABA-responsive element binding protein). Transcription of the AREB1 and AREB2 genes is up-regulated by drought, NaCl, and ABA treatment in vegetative tissues. In a transient transactivation experiment using Arabidopsis leaf protoplasts, both the AREB1 and AREB2 proteins activated transcription of a reporter gene driven by ABRE. AREB1 and AREB2 required ABA for their activation, because their transactivation activities were repressed in aba2 and abi1 mutants and enhanced in an era1 mutant. Activation of AREBs by ABA was suppressed by protein kinase inhibitors. These results suggest that both AREB1 and AREB2 function as transcriptional activators in the ABA-inducible expression of rd29B, and further that ABA-dependent posttranscriptional activation of AREB1 and AREB2, probably by phosphorylation, is necessary for their maximum activation by ABA. Using cultured Arabidopsis cells, we demonstrated that a specific ABA-activated protein kinase of 42-kDa phosphorylated conserved N-terminal regions in the AREB proteins. PMID:11005831

Arabidopsis basic leucine zipper transcription factors involved in an abscisic acid-dependent signal transduction pathway under drought and high-salinity conditions.

PubMed

Uno, Y; Furihata, T; Abe, H; Yoshida, R; Shinozaki, K; Yamaguchi-Shinozaki, K

2000-10-10

The induction of the dehydration-responsive Arabidopsis gene, rd29B, is mediated mainly by abscisic acid (ABA). Promoter analysis of rd29B indicated that two ABA-responsive elements (ABREs) are required for the dehydration-responsive expression of rd29B as cis-acting elements. Three cDNAs encoding basic leucine zipper (bZIP)-type ABRE-binding proteins were isolated by using the yeast one-hybrid system and were designated AREB1, AREB2, and AREB3 (ABA-responsive element binding protein). Transcription of the AREB1 and AREB2 genes is up-regulated by drought, NaCl, and ABA treatment in vegetative tissues. In a transient transactivation experiment using Arabidopsis leaf protoplasts, both the AREB1 and AREB2 proteins activated transcription of a reporter gene driven by ABRE. AREB1 and AREB2 required ABA for their activation, because their transactivation activities were repressed in aba2 and abi1 mutants and enhanced in an era1 mutant. Activation of AREBs by ABA was suppressed by protein kinase inhibitors. These results suggest that both AREB1 and AREB2 function as transcriptional activators in the ABA-inducible expression of rd29B, and further that ABA-dependent posttranscriptional activation of AREB1 and AREB2, probably by phosphorylation, is necessary for their maximum activation by ABA. Using cultured Arabidopsis cells, we demonstrated that a specific ABA-activated protein kinase of 42-kDa phosphorylated conserved N-terminal regions in the AREB proteins.

The Zinc Transporter Zip5 (Slc39a5) Regulates Intestinal Zinc Excretion and Protects the Pancreas against Zinc Toxicity

PubMed Central

Geiser, Jim; De Lisle, Robert C.; Andrews, Glen K.

2013-01-01

Background ZIP5 localizes to the baso-lateral membranes of intestinal enterocytes and pancreatic acinar cells and is internalized and degraded coordinately in these cell-types during periods of dietary zinc deficiency. These cell-types are thought to control zinc excretion from the body. The baso-lateral localization and zinc-regulation of ZIP5 in these cells are unique among the 14 members of the Slc39a family and suggest that ZIP5 plays a role in zinc excretion. Methods/Principal Findings We created mice with floxed Zip5 genes and deleted this gene in the entire mouse or specifically in enterocytes or acinar cells and then examined the effects on zinc homeostasis. We found that ZIP5 is not essential for growth and viability but total knockout of ZIP5 led to increased zinc in the liver in mice fed a zinc-adequate (ZnA) diet but impaired accumulation of pancreatic zinc in mice fed a zinc-excess (ZnE) diet. Loss-of-function of enterocyte ZIP5, in contrast, led to increased pancreatic zinc in mice fed a ZnA diet and increased abundance of intestinal Zip4 mRNA. Finally, loss-of-function of acinar cell ZIP5 modestly reduced pancreatic zinc in mice fed a ZnA diet but did not impair zinc uptake as measured by the rapid accumulation of 67zinc. Retention of pancreatic 67zinc was impaired in these mice but the absence of pancreatic ZIP5 sensitized them to zinc-induced pancreatitis and exacerbated the formation of large cytoplasmic vacuoles containing secretory protein in acinar cells. Conclusions These studies demonstrate that ZIP5 participates in the control of zinc excretion in mice. Specifically, they reveal a paramount function of intestinal ZIP5 in zinc excretion but suggest a role for pancreatic ZIP5 in zinc accumulation/retention in acinar cells. ZIP5 functions in acinar cells to protect against zinc-induced acute pancreatitis and attenuate the process of zymophagy. This suggests that it may play a role in autophagy. PMID:24303081

The prion-ZIP connection: From cousins to partners in iron uptake

PubMed Central

Singh, Neena; Asthana, Abhishek; Baksi, Shounak; Desai, Vilok; Haldar, Swati; Hari, Sahi; Tripathi, Ajai K

2015-01-01

ABSTRACT Converging observations from disparate lines of inquiry are beginning to clarify the cause of brain iron dyshomeostasis in sporadic Creutzfeldt-Jakob disease (sCJD), a neurodegenerative condition associated with the conversion of prion protein (PrPC), a plasma membrane glycoprotein, from α-helical to a β-sheet rich PrP-scrapie (PrPSc) isoform. Biochemical evidence indicates that PrPC facilitates cellular iron uptake by functioning as a membrane-bound ferrireductase (FR), an activity necessary for the transport of iron across biological membranes through metal transporters. An entirely different experimental approach reveals an evolutionary link between PrPC and the Zrt, Irt-like protein (ZIP) family, a group of proteins involved in the transport of zinc, iron, and manganese across the plasma membrane. Close physical proximity of PrPC with certain members of the ZIP family on the plasma membrane and increased uptake of extracellular iron by cells that co-express PrPC and ZIP14 suggest that PrPC functions as a FR partner for certain members of this family. The connection between PrPC and ZIP proteins therefore extends beyond common ancestry to that of functional cooperation. Here, we summarize evidence supporting the facilitative role of PrPC in cellular iron uptake, and implications of this activity on iron metabolism in sCJD brains. PMID:26689487

Memory Retrieval Has a Dynamic Influence on the Maintenance Mechanisms That Are Sensitive to ζ-Inhibitory Peptide (ZIP).

PubMed

Levitan, David; Fortis-Santiago, Yaihara; Figueroa, Joshua A; Reid, Emily E; Yoshida, Takashi; Barry, Nicholas C; Russo, Abigail; Katz, Donald B

2016-10-12

In neuroscientists' attempts to understand the long-term storage of memory, topics of particular importance and interest are the cellular and system mechanisms of maintenance (e.g., those sensitive to ζ-inhibitory peptide, ZIP) and those induced by memory retrieval (i.e., reconsolidation). Much is known about each of these processes in isolation, but less is known concerning how they interact. It is known that ZIP sensitivity and memory retrieval share at least some molecular targets (e.g., recycling α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid, AMPA, receptors to the plasma membrane); conversely, the fact that sensitivity to ZIP emerges only after consolidation ends suggests that consolidation (and by extension reconsolidation) and maintenance might be mutually exclusive processes, the onset of one canceling the other. Here, we use conditioned taste aversion (CTA) in rats, a cortically dependent learning paradigm, to test this hypothesis. First, we demonstrate that ZIP infusions into gustatory cortex begin interfering with CTA memory 43-45 h after memory acquisition-after consolidation ends. Next, we show that a retrieval trial administered after this time point interrupts the ability of ZIP to induce amnesia and that ZIP's ability to induce amnesia is reengaged only 45 h after retrieval. This pattern of results suggests that memory retrieval and ZIP-sensitive maintenance mechanisms are mutually exclusive and that the progression from one to the other are similar after acquisition and retrieval. They also reveal concrete differences between ZIP-sensitive mechanisms induced by acquisition and retrieval: the latency with which ZIP-sensitive mechanisms are expressed differ for the two processes. Memory retrieval and the molecular mechanisms that are sensitive to ζ-inhibitory peptide (ZIP) are the few manipulations that have been shown to effect memory maintenance. Although much is known about their effect on maintenance separately, it is unknown how they

Comparative Genomic Analysis of slc39a12/ZIP12: Insight into a Zinc Transporter Required for Vertebrate Nervous System Development

PubMed Central

Chowanadisai, Winyoo

2014-01-01

The zinc transporter ZIP12, which is encoded by the gene slc39a12, has previously been shown to be important for neuronal differentiation in mouse Neuro-2a neuroblastoma cells and primary mouse neurons and necessary for neurulation during Xenopus tropicalis embryogenesis. However, relatively little is known about the biochemical properties, cellular regulation, or the physiological role of this gene. The hypothesis that ZIP12 is a zinc transporter important for nervous system function and development guided a comparative genetics approach to uncover the presence of ZIP12 in various genomes and identify conserved sequences and expression patterns associated with ZIP12. Ortholog detection of slc39a12 was conducted with reciprocal BLAST hits with the amino acid sequence of human ZIP12 in comparison to the human paralog ZIP4 and conserved local synteny between genomes. ZIP12 is present in the genomes of almost all vertebrates examined, from humans and other mammals to most teleost fish. However, ZIP12 appears to be absent from the zebrafish genome. The discrimination of ZIP12 compared to ZIP4 was unsuccessful or inconclusive in other invertebrate chordates and deuterostomes. Splice variation, due to the inclusion or exclusion of a conserved exon, is present in humans, rats, and cows and likely has biological significance. ZIP12 also possesses many putative di-leucine and tyrosine motifs often associated with intracellular trafficking, which may control cellular zinc uptake activity through the localization of ZIP12 within the cell. These findings highlight multiple aspects of ZIP12 at the biochemical, cellular, and physiological levels with likely biological significance. ZIP12 appears to have conserved function as a zinc uptake transporter in vertebrate nervous system development. Consequently, the role of ZIP12 may be an important link to reported congenital malformations in numerous animal models and humans that are caused by zinc deficiency. PMID:25375179

Interleukin-6 regulates the zinc transporter Zip14 in liver and contributes to the hypozincemia of the acute-phase response

PubMed Central

Liuzzi, Juan P.; Lichten, Louis A.; Rivera, Seth; Blanchard, Raymond K.; Aydemir, Tolunay Beker; Knutson, Mitchell D.; Ganz, Tomas; Cousins, Robert J.

2005-01-01

Infection and inflammation produce systemic responses that include hypozincemia and hypoferremia. The latter involves regulation of the iron transporter ferroportin 1 by hepcidin. The mechanism of reduced plasma zinc is not known. Transcripts of the two zinc transporter gene families (ZnT and Zip) were screened for regulation in mouse liver after turpentine-induced inflammation and LPS administration. Zip14 mRNA was the transporter transcript most up-regulated by inflammation and LPS. IL-6 knockout (IL-6–/–) mice did not exhibit either hypozincemia or the induction of Zip14 with turpentine inflammation. However, in IL-6–/– mice, LPS produced a milder hypozincemic response but no Zip14 induction. Northern analysis showed Zip14 up-regulation was specific for the liver, with one major transcript. Immunohistochemistry, using an antibody to an extracellular Zip14 epitope, showed both LPS and turpentine increased abundance of Zip14 at the plasma membrane of hepatocytes. IL-6 produced increased expression of Zip14 in primary hepatocytes cultures and localization of the protein to the plasma membrane. Transfection of mZip14 cDNA into human embryonic kidney cells increased zinc uptake as measured by both a fluorescent probe for free Zn2+ and 65Zn accumulation, as well as by metallothionein mRNA induction, all indicating that Zip14 functions as a zinc importer. Zip14 was localized in plasma membrane of the transfected cells. These in vivo and in vitro experiments demonstrate that Zip14 expression is up-regulated through IL-6, and that this zinc transporter most likely plays a major role in the mechanism responsible for hypozincemia that accompanies the acute-phase response to inflammation and infection. PMID:15863613

Zipper model for the melting of thin films

NASA Astrophysics Data System (ADS)

Abdullah, Mikrajuddin; Khairunnisa, Shafira; Akbar, Fathan

2016-01-01

We propose an alternative model to Lindemann’s criterion for melting that explains the melting of thin films on the basis of a molecular zipper-like mechanism. Using this model, a unique criterion for melting is obtained. We compared the results of the proposed model with experimental data of melting points and heat of fusion for many materials and obtained interesting results. The interesting thing reported here is how complex physics problems can sometimes be modeled with simple objects around us that seemed to have no correlation. This kind of approach is sometimes very important in physics education and should always be taught to undergraduate or graduate students.

Feedback Regulation of ABA Signaling and Biosynthesis by a bZIP Transcription Factor Targets Drought-Resistance-Related Genes1[OPEN

PubMed Central

Tang, Ning; Yang, Jun; Peng, Lei; Ma, Siqi; Xu, Yan; Li, Guoliang

2016-01-01

The OsbZIP23 transcription factor has been characterized for its essential role in drought resistance in rice (Oryza sativa), but the mechanism is unknown. In this study, we first investigated the transcriptional activation of OsbZIP23. A homolog of SnRK2 protein kinase (SAPK2) was found to interact with and phosphorylate OsbZIP23 for its transcriptional activation. SAPK2 also interacted with OsPP2C49, an ABI1 homolog, which deactivated the SAPK2 to inhibit the transcriptional activation activity of OsbZIP23. Next, we performed genome-wide identification of OsbZIP23 targets by immunoprecipitation sequencing and RNA sequencing analyses in the OsbZIP23-overexpression, osbzip23 mutant, and wild-type rice under normal and drought stress conditions. OsbZIP23 directly regulates a large number of reported genes that function in stress response, hormone signaling, and developmental processes. Among these targets, we found that OsbZIP23 could positively regulate OsPP2C49, and overexpression of OsPP2C49 in rice resulted in significantly decreased sensitivity of the abscisic acid (ABA) response and rapid dehydration. Moreover, OsNCED4 (9-cis-epoxycarotenoid dioxygenase4), a key gene in ABA biosynthesis, was also positively regulated by OsbZIP23. Together, our results suggest that OsbZIP23 acts as a central regulator in ABA signaling and biosynthesis, and drought resistance in rice. PMID:27325665

Five Easy Principles to Make Math Moments Count

ERIC Educational Resources Information Center

Cutler, Carrie S.

2011-01-01

Preschool children are learning so many skills--how to cut with scissors, zip zippers, recognize the alphabet and their names, and share toys with others. A strong academic curriculum also requires that children learn more about math (National Council of Teachers of Mathematics [NCTM], 2000). By following the five easy principles outlined here,…

Search for Exoplanets around Northern Circumpolar Stars. II. The Detection of Radial Velocity Variations in M Giant Stars HD 36384, HD 52030, and HD 208742

NASA Astrophysics Data System (ADS)

Lee, Byeong-Cheol; Jeong, Gwanghui; Park, Myeong-Gu; Han, Inwoo; Mkrtichian, David E.; Hatzes, Artie P.; Gu, Shenghong; Bai, Jinming; Lee, Sang-Min; Oh, Hyeong-Il; Kim, Kang-Min

2017-07-01

We present the detection of long-period RV variations in HD 36384, HD 52030, and HD 208742 by using the high-resolution, fiber-fed Bohyunsan Observatory Echelle Spectrograph (BOES) for the precise radial velocity (RV) survey of about 200 northern circumpolar stars. Analyses of RV data, chromospheric activity indicators, and bisector variations spanning about five years suggest that the RV variations are compatible with planet or brown dwarf companions in Keplerian motion. However, HD 36384 shows photometric variations with a period very close to that of RV variations as well as amplitude variations in the weighted wavelet Z-transform (WWZ) analysis, which argues that the RV variations in HD 36384 are from the stellar pulsations. Assuming that the companion hypothesis is correct, HD 52030 hosts a companion with minimum mass 13.3 M Jup orbiting in 484 days at a distance of 1.2 au. HD 208742 hosts a companion of 14.0 M Jup at 1.5 au with a period of 602 days. All stars are located at the asymptotic giant branch (AGB) stage on the H-R diagram after undergoing the helium flash and leaving the giant clump.With stellar radii of 53.0 R ⊙ and 57.2 R ⊙ for HD 52030 and HD 208742, respectively, these stars may be the largest yet, in terms of stellar radius, found to host substellar companions. However, given possible RV amplitude variations and the fact that these are highly evolved stars, the planet hypothesis is not yet certain.

Search for Exoplanets around Northern Circumpolar Stars. II. The Detection of Radial Velocity Variations in M Giant Stars HD 36384, HD 52030, and HD 208742

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

Lee, Byeong-Cheol; Jeong, Gwanghui; Han, Inwoo

2017-07-20

We present the detection of long-period RV variations in HD 36384, HD 52030, and HD 208742 by using the high-resolution, fiber-fed Bohyunsan Observatory Echelle Spectrograph (BOES) for the precise radial velocity (RV) survey of about 200 northern circumpolar stars. Analyses of RV data, chromospheric activity indicators, and bisector variations spanning about five years suggest that the RV variations are compatible with planet or brown dwarf companions in Keplerian motion. However, HD 36384 shows photometric variations with a period very close to that of RV variations as well as amplitude variations in the weighted wavelet Z-transform (WWZ) analysis, which argues thatmore » the RV variations in HD 36384 are from the stellar pulsations. Assuming that the companion hypothesis is correct, HD 52030 hosts a companion with minimum mass 13.3 M {sub Jup} orbiting in 484 days at a distance of 1.2 au. HD 208742 hosts a companion of 14.0 M {sub Jup} at 1.5 au with a period of 602 days. All stars are located at the asymptotic giant branch (AGB) stage on the H–R diagram after undergoing the helium flash and leaving the giant clump.With stellar radii of 53.0 R {sub ⊙} and 57.2 R {sub ⊙} for HD 52030 and HD 208742, respectively, these stars may be the largest yet, in terms of stellar radius, found to host substellar companions. However, given possible RV amplitude variations and the fact that these are highly evolved stars, the planet hypothesis is not yet certain.« less

Magnetic field geometries of two slowly rotating Ap/Bp stars: HD 12288 and HD 14437

NASA Astrophysics Data System (ADS)

Wade, G. A.; Kudryavtsev, D.; Romanyuk, I. I.; Landstreet, J. D.; Mathys, G.

2000-03-01

In this paper we report magnetic field models and basic physical parameters for the slowly rotating Ap/Bp stars HD 12288 and HD 14437. Using new and previously published mean longitudinal magnetic field, mean magnetic field modulus, and hipparcos photometric measurements, we have inferred the rotational periods of both stars (HD 12288: P_rot=34.9d +/- 0.2d HD 14437: P_rot=26.87d +/- 0.02d). From the magnetic measurements we have determined the best-fit decentred magnetic dipole configurations. For HD 12288, we find that the field geometry is consistent with a centred dipole, while for HD 14437 a large decentring parameter (a=0.23 R_*) is inferred. Both stars show one angle in the ambiguous (i,beta ) couplet which is smaller than about 20degr . This is consistent with the observation of Landstreet & Mathys (2000), who point out that almost all magnetic Ap stars with periods longer than about 30 days exhibit magnetic fields aligned with their rotational axis.

LiZIP3 is a cellular zinc transporter that mediates the tightly regulated import of zinc in Leishmania infantum parasites

PubMed Central

Carvalho, Sandra; da Silva, Rosa Barreira; Shawki, Ali; Castro, Helena; Lamy, Márcia; Eide, David; Costa, Vítor; Mackenzie, Bryan; Tomás, Ana M.

2016-01-01

Summary Cellular zinc homeostasis ensures that the intracellular concentration of this element is kept within limits that enable its participation in critical physiological processes without exerting toxic effects. We report here the identification and characterization of the first mediator of zinc homeostasis in Leishmania infantum, LiZIP3, a member of the ZIP family of divalent metal-ion transporters. The zinc transporter activity of LiZIP3 was first disclosed by its capacity to rescue the growth of Saccharomyces cerevisiae strains deficient in zinc acquisition. Subsequent expression of LiZIP3 in Xenopus laevis oocytes was shown to stimulate the uptake of a broad range of metal ions, among which Zn2+ was the preferred LiZIP3 substrate (K0.5 ≈ 0.1 μM). Evidence that LiZIP3 functions as a zinc importer in L. infantum came from the observations that the protein locates to the cell membrane and that its overexpression leads to augmented zinc internalization. Importantly, expression and cell-surface location of LiZIP3 are lost when parasites face high zinc bioavailability. LiZIP3 decline in response to zinc is regulated at the mRNA level in a process involving (a) short-lived protein(s). Collectively, our data reveal that LiZIP3 enables L. infantum to acquire zinc in a highly regulated manner, hence contributing to zinc homeostasis. PMID:25644708

PSD-Zip70 Deficiency Causes Prefrontal Hypofunction Associated with Glutamatergic Synapse Maturation Defects by Dysregulation of Rap2 Activity.

PubMed

Mayanagi, Taira; Yasuda, Hiroki; Sobue, Kenji

2015-10-21

Dysregulation of synapse formation and plasticity is closely related to the pathophysiology of psychiatric and neurodevelopmental disorders. The prefrontal cortex (PFC) is particularly important for executive functions such as working memory, cognition, and emotional control, which are impaired in the disorders. PSD-Zip70 (Lzts1/FEZ1) is a postsynaptic density (PSD) protein predominantly expressed in the frontal cortex, olfactory bulb, striatum, and hippocampus. Here we found that PSD-Zip70 knock-out (PSD-Zip70KO) mice exhibit working memory and cognitive defects, and enhanced anxiety-like behaviors. These abnormal behaviors are caused by impaired glutamatergic synapse transmission accompanied by tiny-headed immature dendritic spines in the PFC, due to aberrant Rap2 activation, which has roles in synapse formation and plasticity. PSD-Zip70 modulates the Rap2 activity by interacting with SPAR (spine-associated RapGAP) and PDZ-GEF1 (RapGEF) in the postsynapse. Furthermore, suppression of the aberrant Rap2 activation in the PFC rescued the behavioral defects in PSD-Zip70KO mice. Our data demonstrate a critical role for PSD-Zip70 in Rap2-dependent spine synapse development in the PFC and underscore the importance of this regulation in PFC-dependent behaviors. PSD-Zip70 deficiency causes behavioral defects in working memory and cognition, and enhanced anxiety due to prefrontal hypofunction. This study revealed that PSD-Zip70 plays essential roles in glutamatergic synapse maturation via modulation of the Rap2 activity in the PFC. PSD-Zip70 interacts with both SPAR (spine-associated RapGAP) and PDZ-GEF1 (RapGEF) and modulates the Rap2 activity in postsynaptic sites. Our results provide a novel Rap2-specific regulatory mechanism in synaptic maturation involving PSD-Zip70. Copyright © 2015 the authors 0270-6474/15/3514327-14$15.00/0.

Line profile variability in the massive binary HD 152219

NASA Astrophysics Data System (ADS)

Sana, H.; Gosset, E.

2009-07-01

HD 152219 is a massive binary system with O9.5 III and B1-2 III/V components and a short orbital period of 4.2 d. In a previous work, we showed that the primary star (M_{prim}˜21 M_⊙) was presenting clear line profile variabilities (LPVs) that might be caused by nonradial pulsations (NRPs). In the present work, we report on an intensive spectroscopic monitoring, that aimed at unveiling the nature of the detected LPVs. Based on this new data set, we discard the NRPs and point out the Rossiter-McLaughlin effect as % being the cause of the observed LPVs. The upper limit derived on the amplitude of undetected NRPs, if any, is set at a couple of part per thousands of the continuum level.

Modulation of phase transition of thermosensitive liposomes with leucine zipper-structured lipopeptides.

PubMed

Xu, Xiejun; Xiao, Xingqing; Wang, Yiming; Xu, Shouhong; Liu, Honglai

2018-06-13

Targeted therapy for cancer requires thermosensitive components in drug carriers for controlled drug release against viral cells. The conformational transition characteristic of leucine zipper-structured lipopeptides is utilized in our lab to modulate the phase transition temperature of liposomes, thus achieving temperature-responsive control. In this study, we computationally examined the conformational transition behaviors of leucine zipper-structured lipopeptides that were modified at the N-terminus by distinct functional groups. The conformational transition temperatures of these lipopeptides were determined by structural analysis of the implicit-solvent replica exchange molecular dynamics simulation trajectories using the dihedral angle principal component analysis and the dictionary of protein secondary structure method. Our calculations revealed that the computed transition temperatures of the lipopeptides are in good agreement with the experimental measurements. The effect of hydrogen bonds on the conformational stability of the lipopeptide dimers was examined in conventional explicit-solvent molecular dynamics simulations. A quantitative correlation of the degree of structural dissociation of the dimers and their binding strength is well described by an exponential fit of the binding free energies to the conformation transition temperatures of the lipopeptides.

Dimerization of the SP1 Region of HIV-1 Gag Induces a Helical Conformation and Association into Helical Bundles: Implications for Particle Assembly.

PubMed

Datta, Siddhartha A K; Clark, Patrick K; Fan, Lixin; Ma, Buyong; Harvin, Demetria P; Sowder, Raymond C; Nussinov, Ruth; Wang, Yun-Xing; Rein, Alan

2016-02-15

HIV-1 immature particle (virus-like particle [VLP]) assembly is mediated largely by interactions between the capsid (CA) domains of Gag molecules but is facilitated by binding of the nucleocapsid (NC) domain to nucleic acid. We previously investigated the role of SP1, a "spacer" between CA and NC, in VLP assembly. We found that small changes in SP1 drastically disrupt assembly and that a peptide representing the sequence around the CA-SP1 junction is helical at high but not low concentrations. We suggested that by virtue of such a concentration-dependent change, this region could act as a molecular switch to activate HIV-1 Gag for VLP assembly. A leucine zipper domain can replace NC in Gag and still lead to the efficient assembly of VLPs. We find that SP1 mutants also disrupt assembly by these Gag-Zip proteins and have now studied a small fragment of this Gag-Zip protein, i.e., the CA-SP1 junction region fused to a leucine zipper. Dimerization of the zipper places SP1 at a high local concentration, even at low total concentrations. In this context, the CA-SP1 junction region spontaneously adopts a helical conformation, and the proteins associate into tetramers. Tetramerization requires residues from both CA and SP1. The data suggest that once this region becomes helical, its propensity to self-associate could contribute to Gag-Gag interactions and thus to particle assembly. There is complete congruence between CA/SP1 sequences that promote tetramerization when fused to zippers and those that permit the proper assembly of full-length Gag; thus, equivalent interactions apparently participate in VLP assembly and in SP1-Zip tetramerization. Assembly of HIV-1 Gag into virus-like particles (VLPs) appears to require an interaction with nucleic acid, but replacement of its principal nucleic acid-binding domain with a dimerizing leucine zipper domain leads to the assembly of RNA-free VLPs. It has not been clear how dimerization triggers assembly. Results here show that the

Dimerization of the SP1 Region of HIV-1 Gag Induces a Helical Conformation and Association into Helical Bundles: Implications for Particle Assembly

PubMed Central

Clark, Patrick K.; Fan, Lixin; Ma, Buyong; Harvin, Demetria P.; Sowder, Raymond C.; Nussinov, Ruth; Wang, Yun-Xing

2015-01-01

ABSTRACT HIV-1 immature particle (virus-like particle [VLP]) assembly is mediated largely by interactions between the capsid (CA) domains of Gag molecules but is facilitated by binding of the nucleocapsid (NC) domain to nucleic acid. We previously investigated the role of SP1, a “spacer” between CA and NC, in VLP assembly. We found that small changes in SP1 drastically disrupt assembly and that a peptide representing the sequence around the CA-SP1 junction is helical at high but not low concentrations. We suggested that by virtue of such a concentration-dependent change, this region could act as a molecular switch to activate HIV-1 Gag for VLP assembly. A leucine zipper domain can replace NC in Gag and still lead to the efficient assembly of VLPs. We find that SP1 mutants also disrupt assembly by these Gag-Zip proteins and have now studied a small fragment of this Gag-Zip protein, i.e., the CA-SP1 junction region fused to a leucine zipper. Dimerization of the zipper places SP1 at a high local concentration, even at low total concentrations. In this context, the CA-SP1 junction region spontaneously adopts a helical conformation, and the proteins associate into tetramers. Tetramerization requires residues from both CA and SP1. The data suggest that once this region becomes helical, its propensity to self-associate could contribute to Gag-Gag interactions and thus to particle assembly. There is complete congruence between CA/SP1 sequences that promote tetramerization when fused to zippers and those that permit the proper assembly of full-length Gag; thus, equivalent interactions apparently participate in VLP assembly and in SP1-Zip tetramerization. IMPORTANCE Assembly of HIV-1 Gag into virus-like particles (VLPs) appears to require an interaction with nucleic acid, but replacement of its principal nucleic acid-binding domain with a dimerizing leucine zipper domain leads to the assembly of RNA-free VLPs. It has not been clear how dimerization triggers assembly

Spectrophotometry of peculiar B and A stars. XIV - 56 Arietis, 41 Tauri, 25 Sextantis, HD 170973, HD 205087, and HD 215441

NASA Astrophysics Data System (ADS)

Adelman, S. J.

1983-03-01

Optical region spectrophotometry of six relatively hot Ap stars is presented. Additional scans of 56 Ari extend the results of an earlier paper in this series. The data for 41 Tau, 25 Sex, HD 170973, and HD 215441 are studied as a function of phase. The observations of HD 205087 are inconclusive about its variability although they show spectrophotometrically that it is a definite Ap star. The observations of HD 215441 show a prominent λ5200 broad, continuum feature with an unusual shape. However, when the data are corrected for interstellar reddening, the energy distribution resembles those of other silicon stars. The λ5200 feature is found to be variable in phase with the U-B and B-V colors and with the magnetic field strength. This feature is strongest when the Balmer jump is smallest, the Paschen continuum the bluest according to B-V, and the surface magnetic field strength the largest.

Project VeSElkA: abundance analysis of chemical species in HD 41076 and HD 148330

NASA Astrophysics Data System (ADS)

Khalack, V.; Gallant, G.; Thibeault, C.

2017-10-01

A new semi-automatic approach is employed to carry out the abundance analysis of high-resolution spectra of HD 41076 and HD 148330 obtained recently with the spectropolarimetre Echelle SpectroPolarimetric Device for Observations of Stars at the Canada-France-Hawaii Telescope. This approach allows to prepare in a semi-automatic mode the input data for the modified zeeman2 code and to analyse several hundreds of line profiles in sequence during a single run. It also provides more information on abundance distribution for each chemical element at the deeper atmospheric layers. Our analysis of the Balmer profiles observed in the spectra of HD 41076 and HD 148330 has resulted in the estimates of their effective temperature, gravity, metallicity and radial velocity. The respective models of stellar atmosphere have been calculated with the code phoenix and used to carry out abundance analysis employing the modified zeeman2 code. The analysis shows a deficit of the C, N, F, Mg, Ca, Ti, V, Cu, Y, Mo, Sm and Gd, and overabundance of Cr, Mn, Fe, Co, Ni, Sr, Zr, Ba, Ce, Nd and Dy in the stellar atmosphere of HD 41076. In the atmosphere of HD 148330, the C, N and Mo appear to be underabundant, while the Ne, Na, Al, Si, P, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, Sr, Y, Zr, Ba, Ce, Pr, Nd, Sm, Eu, Gd and Dy are overabundant. We also have found signatures of vertical abundance stratification of Fe, Ti, Cr and Mn in HD 41076, and of Fe, Ti, V, Cr, Mn, Y, Zr, Ce, Nd, Sm and Gd in HD 148330.

Zip Pak (Boys) for Third Reader Level.

ERIC Educational Resources Information Center

Scott, Norval C., Comp.

Aim of the Zip Pak is to improve the migrant child's interest in reading. Behavioral objectives are to have the migrant child indicate 10 percent happier faces on the posttest; to have an equal number of blame-self, blame-others on the posttest; and to have 25 percent more praise-self on the posttest. The workbook for boys includes a story about…

Dual Leucine Zipper Kinase Inhibitors for the Treatment of Neurodegeneration.

PubMed

Siu, Michael; Sengupta Ghosh, Arundhati; Lewcock, Joseph W

2018-06-04

Dual leucine zipper kinase (DLK, MAP3K12) is an essential driver of the neuronal stress response that regulates neurodegeneration in models of acute neuronal injury and chronic neurodegenerative diseases such as Alzheimer's, Parkinson's, and ALS. In this review, we provide an overview of DLK signaling mechanisms and describe selected small molecules that have been utilized to inhibit DLK kinase activity in vivo. These compounds represent valuable tools for understanding the role of DLK signaling and evaluating the potential for DLK inhibition as a therapeutic strategy to prevent neuronal degeneration.

Long-Term Follow-Up of Contemporary Treatment in Early-Stage Hodgkin Lymphoma: Updated Analyses of the German Hodgkin Study Group HD7, HD8, HD10, and HD11 Trials.

PubMed

Sasse, Stephanie; Bröckelmann, Paul J; Goergen, Helen; Plütschow, Annette; Müller, Horst; Kreissl, Stefanie; Buerkle, Carolin; Borchmann, Sven; Fuchs, Michael; Borchmann, Peter; Diehl, Volker; Engert, Andreas

2017-06-20

Purpose Combined-modality treatment is widely considered the standard of care in early-stage Hodgkin lymphoma (HL), and treatment intensity has been reduced over the last years. Long-term follow-up is important to judge both efficacy and safety of the different therapies used. Patients and Methods We analyzed updated follow-up data on 4,276 patients treated within the German Hodgkin Study Group trials HD7 and HD10 for early-stage favorable HL and HD8 and HD11 for early-stage unfavorable HL between 1993 and 2003. Results In HD7 (N = 627; median follow-up, 120 months), combined-modality treatment was superior to extended-field radiotherapy (RT), with 15-year progression-free survival (PFS) of 73% versus 52% (hazard ratio [HR], 0.5; 95% CI, 0.3 to 0.6; P < .001), without differences in overall survival (OS). In HD10 (N = 1,190; median follow-up, 98 months), noninferiority of two cycles of doxorubicin, bleomycin, vinblastine, dacarbazine (ABVD) plus 20 Gy involved-field (IF)-RT to more intensive four cycles of ABVD plus 30 Gy IF-RT was confirmed with 10-year PFS of 87% each (HR, 1.0; 95%, 0.6 to 1.5) and OS of 94% each (HR, 0.9; 95% CI, 0.5 to 1.6), respectively. In both trials, no differences in second neoplasias were observed. In HD8 (N = 1,064; median follow-up, 153 months), noninferiority of involved-field RT to extended-field RT regarding PFS was confirmed (HR, 1.0; 95% CI, 0.8 to 1.2). In HD11 (N = 1,395; median follow-up, 106 months), superiority of bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone at baseline over ABVD was not observed. After BEACOPP baseline , 20 Gy IF-RT was noninferior to 30 Gy (10-year PFS, 84% v 84%; HR, 1.0; 95% CI, 0.7 to 1.5). In contrast, PFS was inferior in ABVD-treated patients receiving 20 Gy instead of 30 Gy IF-RT (10-year PFS, 76% v 84%; HR, 1.5; 95% CI, 1.0 to 2.1). No differences in OS or second neoplasias were observed in in both trials. Conclusion Long-term follow-up data of the

Development of the HD-Teen Inventory

PubMed Central

Driessnack, Martha; Williams, Janet K.; Barnette, J. Jackson; Sparbel, Kathleen J.; Paulsen, Jane S.

2013-01-01

Adolescents, who have a parent with Huntington Disease (HD), not only are at genetic risk for HD but also are witness to its onset and devastating clinical progression as their parent declines. To date, no mechanism has been developed to direct health care providers to the atypical adolescent experiences of these teens. The purpose of this report is to describe the process of developing the HD-Teen Inventory clinical assessment tool. Forty-eight teens and young adults from 19 U.S. states participated in the evaluation of the HD-Teen Inventory tool. Following item analysis, the number of items was reduced and item frequency and reaction scales were combined, based on the strong correlation (r = .94). The resultant tool contains 15 inventory and 2 open-ended response items. The HD-Teen Inventory emerged as a more compact and efficient tool for identifying the most salient concerns of at-risk teens in HD families in research and/or clinical practice. PMID:21632913

Development of the HD-Teen Inventory.

PubMed

Driessnack, Martha; Williams, Janet K; Barnette, J Jackson; Sparbel, Kathleen J; Paulsen, Jane S

2012-05-01

Adolescents, who have a parent with Huntington Disease (HD), not only are at genetic risk for HD but also are witness to its onset and devastating clinical progression as their parent declines. To date, no mechanism has been developed to direct health care providers to the atypical adolescent experiences of these teens. The purpose of this report is to describe the process of developing the HD-Teen Inventory clinical assessment tool. Forty-eight teens and young adults from 19 U.S. states participated in the evaluation of the HD-Teen Inventory tool. Following item analysis, the number of items was reduced and item frequency and reaction scales were combined, based on the strong correlation (r = .94). The resultant tool contains 15 inventory and 2 open-ended response items. The HD-Teen Inventory emerged as a more compact and efficient tool for identifying the most salient concerns of at-risk teens in HD families in research and/or clinical practice.

Conditional mouse models support the role of SLC39A14 (ZIP14) in Hyperostosis Cranialis Interna and in bone homeostasis

PubMed Central

Steenackers, Ellen; Yorgan, Timur A.; Hermans, Christophe; Boudin, Eveline; Waterval, Jérôme J.; Jansen, Ineke D. C.; Aydemir, Tolunay Beker; Kamerling, Niels; Plumeyer, Christine; D’Haese, Patrick C.; Everts, Vincent; Lammens, Martin; Mortier, Geert; Cousins, Robert J.; Schinke, Thorsten; Stokroos, Robert J.; Manni, Johannes J.; Van Hul, Wim

2018-01-01

Hyperostosis Cranialis Interna (HCI) is a rare bone disorder characterized by progressive intracranial bone overgrowth at the skull. Here we identified by whole-exome sequencing a dominant mutation (L441R) in SLC39A14 (ZIP14). We show that L441R ZIP14 is no longer trafficked towards the plasma membrane and excessively accumulates intracellular zinc, resulting in hyper-activation of cAMP-CREB and NFAT signaling. Conditional knock-in mice overexpressing L438R Zip14 in osteoblasts have a severe skeletal phenotype marked by a drastic increase in cortical thickness due to an enhanced endosteal bone formation, resembling the underlying pathology in HCI patients. Remarkably, L438R Zip14 also generates an osteoporotic trabecular bone phenotype. The effects of osteoblastic overexpression of L438R Zip14 therefore mimic the disparate actions of estrogen on cortical and trabecular bone through osteoblasts. Collectively, we reveal ZIP14 as a novel regulator of bone homeostasis, and that manipulating ZIP14 might be a therapeutic strategy for bone diseases. PMID:29621230

The nature of dust around the post-asymptotic giant branch objects HD 161796 and HD 179821

NASA Technical Reports Server (NTRS)

Justtanont, K.; Barlow, M. J.; Skinner, C. J.; Tielens, A. G. G. M.

1992-01-01

Ground-based 7.4-24-micron spectra of two post-AGB objects, HD 161796 and HD 179821, are reported, and they are compared to those of other preplanetary nebulae. HD 161796 and HD 17982 show emission features at 10-12 microns and at 10 microns, and they exhibit a very rapid increase in flux between 13 and 15.5 microns. In view of the O-rich photosphere of HD 161796 and the presence of OH maser emission around all three objects, these features are ascribed to various oxides. The observed spectral features are quite different from the canonical silicate features observed in most O-rich giants. It is argued that HD 161796 and the bipolar nebulae Roberts 22 and NGC 6302 have all undergone the third dredge-up, with most of the dredged-up carbon having been converted to nitrogen by envelope-burning. It is concluded that carbon-rich grain material, produced during the interval between the end of the third dredge-up and the moment when envelope burning finally reduced the C/O ratio below unity again, could be responsible for the UIR bands now being excited in Roberts 22 and NGC 6302.

Dissection of Arabidopsis NCED9 promoter regulatory regions reveals a role for ABA synthesized in embryos in the regulation of GA-dependent seed germination.

PubMed

Seo, Mitsunori; Kanno, Yuri; Frey, Anne; North, Helen M; Marion-Poll, Annie

2016-05-01

Nine-cis-epoxycarotenoid dioxygenase (NCED) catalyzes the key step of abscisic acid (ABA) biosynthesis. There are five genes encoding NCED in Arabidopsis, which differentially regulate ABA biosynthesis in a spatiotemporal manner in response to endogenous and environmental stimuli. Previous studies have shown that NCED9 is expressed in testa and embryos during seed development. In the present study, we have identified promoter regions required for the expression of NCED9 in testa and embryos, respectively. Electrophoretic mobility shift assays (EMSA) and yeast one-hybrid (Y1H) assays showed that several homeodomain-leucine zipper (HD-Zip) proteins, namely ATHBs, bound to the sequence required for expression of NCED9 in testa, suggesting that they redundantly regulate NCED9 expression. By expressing the NCED9 gene under the control of a deleted NCED9 promoter in an nced9 mutant expression was limited to embryos. Transformants were complemented for the paclobutrazol resistant germination phenotype of the mutant, suggesting that the ABA synthesis mediated by NCED9 in embryos plays an important role in the regulation of gibberellin (GA)-dependent seed germination. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Two ABREs, two redundant root-specific and one W-box cis-acting elements are functional in the sunflower HAHB4 promoter.

PubMed

Manavella, Pablo A; Dezar, Carlos A; Ariel, Federico D; Chan, Raquel L

2008-10-01

HAHB4 is a sunflower gene encoding a homeodomain-leucine zipper (HD-Zip) transcription factor. It was previously demonstrated that this gene is regulated at the transcriptional level by several abiotic factors and hormones. A previous analysis in the PLACE database revealed the presence of four putative ABREs. In this work these four elements and also one W-box and two root-specific expression elements were characterized as functional. Site-directed mutagenesis on the promoter, stable transformation of Arabidopis plants as well as transient transformation of sunflower leaves, were performed. The analysis of the transformants was carried out by histochemistry and real time RT-PCR. The results indicate that just one ABRE out of the four is responsible for ABA, NaCl and drought regulation. However, NaCl induction occurs also by an additional ABA-independent way involving another two overlapped ABREs. On the other hand, it was determined that the W-box located 5' upstream is responsive to ethylene and only two root-specific expression elements, among the several detected, are functional but redundant. Conservation of molecular mechanisms between sunflower and Arabidopsis is strongly supported by this experimental work.

Copious amounts of hot and cold dust orbiting the main sequence a-type stars HD 131488 and HD 121191

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

Melis, Carl; Zuckerman, B.; Rhee, Joseph H.

2013-11-20

We report two new dramatically dusty main sequence stars: HD 131488 (A1 V) and HD 121191 (A8 V). HD 131488 is found to have substantial amounts of dust in its terrestrial planet zone (L {sub IR}/L {sub bol} ≈ 4 × 10{sup –3}), cooler dust farther out in its planetary system, and an unusual mid-infrared spectral feature. HD 121191 shows terrestrial planet zone dust (L {sub IR}/L {sub bol} ≈ 2.3 × 10{sup –3}), hints of cooler dust, and shares the unusual mid-infrared spectral shape identified in HD 131488. These two stars belong to sub-groups of the Scorpius-Centaurus OB associationmore » and have ages of ∼10 Myr. HD 131488 and HD 121191 are the dustiest main sequence A-type stars currently known. Early-type stars that host substantial inner planetary system dust are thus far found only within the age range of 5-20 Myr.« less

A novel bZIP transcription factor ClrC positively regulates multiple stress responses, conidiation and cellulase expression in Penicillium oxalicum.

PubMed

Lei, Yunfeng; Liu, Guodong; Yao, Guangshan; Li, Zhonghai; Qin, Yuqi; Qu, Yinbo

2016-06-01

Cellulase production in filamentous fungi is largely regulated at the transcriptional level, and several transcription factors have been reported to be involved in this process. In this study, we identified ClrC, a novel transcription factor in cellulase production in Penicillium oxalicum. ClrC and its orthologs have a highly conserved basic leucine zipper (bZIP) DNA binding domain, and their biological functions have not been explored. Deletion of clrC resulted in pleiotropic effects, including altered growth, reduced conidiation and increased sensitivity to oxidative and cell wall stresses. In particular, the clrC deletion mutant ΔclrC showed 46.1% ± 8.1% and 58.0% ± 8.7% decreases in production of filter paper enzyme and xylanase activities in cellulose medium, respectively. In contrast, 57.4% ± 10.0% and 70.9% ± 19.4% increased production of filter paper enzyme, and xylanase was observed in the clrC overexpressing strain, respectively. The transcription levels of major cellulase genes, as well as two cellulase transcriptional activator genes, clrB and xlnR, were significantly downregulated in ΔclrC, but substantially upregulated in clrC overexpressing strains. Furthermore, we observed that the absence of ClrC reduced full induction of cellulase expression even in the clrB overexpressing strain. These results indicated that ClrC is a novel and efficient engineering target for improving cellulolytic enzyme production in filamentous fungi. Copyright © 2016 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Dynamical Simulations of HD 69830

NASA Astrophysics Data System (ADS)

Payne, Matthew J.; Ford, Eric B.; Wyatt, Mark C.; Booth, Mark

2009-02-01

Previous studies have developed models for the growth and migration of three planets orbiting HD 69830. We perform n-body simulations using MERCURY (Chambers 1999) to explore the implications of these models for: 1) the excitation of planetary orbits via planet-planet interactions, 2) the accretion and clearing of a putative planetesimal disk, 3) the distribution of planetesimal orbits following migration, and 4) the implications for the origin of the observed infrared emission from the HD 69830 system. We report preliminary results that suggest new constraints on the formation of HD 69830.

Precise Ages for the Benchmark Brown Dwarfs HD 19467 B and HD 4747 B

NASA Astrophysics Data System (ADS)

Wood, Charlotte; Boyajian, Tabetha; Crepp, Justin; von Braun, Kaspar; Brewer, John; Schaefer, Gail; Adams, Arthur; White, Tim

2018-01-01

Large uncertainty in the age of brown dwarfs, stemming from a mass-age degeneracy, makes it difficult to constrain substellar evolutionary models. To break the degeneracy, we need ''benchmark" brown dwarfs (found in binary systems) whose ages can be determined independent of their masses. HD~19467~B and HD~4747~B are two benchmark brown dwarfs detected through the TRENDS (TaRgeting bENchmark objects with Doppler Spectroscopy) high-contrast imaging program for which we have dynamical mass measurements. To constrain their ages independently through isochronal analysis, we measured the radii of the host stars with interferometry using the Center for High Angular Resolution Astronomy (CHARA) Array. Assuming the brown dwarfs have the same ages as their host stars, we use these results to distinguish between several substellar evolutionary models. In this poster, we present new age estimates for HD~19467 and HD~4747 that are more accurate and precise and show our preliminary comparisons to cooling models.

Project VeSElkA: results of abundance analysis for HD 53929 and HD 63975

NASA Astrophysics Data System (ADS)

Ndiaye, M. L.; LeBlanc, F.; Khalack, V.

2018-03-01

Project VeSElkA (Vertical Stratification of Element Abundances) has been initiated with the aim to detect and study the vertical stratification of element abundances in the atmosphere of chemically peculiar stars. Abundance stratification occurs in hydrodynamically stable stellar atmospheres due to the migration of the elements caused by atomic diffusion. Two HgMn stars, HD 53929 and HD 63975 were selected from the VeSElkA sample and analysed with the aim to detect some abundance peculiarities employing the ZEEMAN2 code. We present the results of abundance analysis of HD 53929 and HD 63975 observed recently with the spectropolarimeter ESPaDOnS at Canada-France-Hawaii Telescope. Evidence of phosphorus vertical stratification was detected in the atmosphere of these two stars. In both cases, phosphorus abundance increases strongly towards the superficial layers. The strong overabundance of Mn found in stellar atmosphere of both stars confirms that they are HgMn type stars.

Decryption-decompression of AES protected ZIP files on GPUs

NASA Astrophysics Data System (ADS)

Duong, Tan Nhat; Pham, Phong Hong; Nguyen, Duc Huu; Nguyen, Thuy Thanh; Le, Hung Duc

2011-10-01

AES is a strong encryption system, so decryption-decompression of AES encrypted ZIP files requires very large computing power and techniques of reducing the password space. This makes implementations of techniques on common computing system not practical. In [1], we reduced the original very large password search space to a much smaller one which surely containing the correct password. Based on reduced set of passwords, in this paper, we parallel decryption, decompression and plain text recognition for encrypted ZIP files by using CUDA computing technology on graphics cards GeForce GTX295 of NVIDIA, to find out the correct password. The experimental results have shown that the speed of decrypting, decompressing, recognizing plain text and finding out the original password increases about from 45 to 180 times (depends on the number of GPUs) compared to sequential execution on the Intel Core 2 Quad Q8400 2.66 GHz. These results have demonstrated the potential applicability of GPUs in this cryptanalysis field.

Geometric phase effects in ultracold collisions of H/D with rotationally excited HD

NASA Astrophysics Data System (ADS)

Kendrick, Brian K.; Croft, James F. E.; Hazra, Jisha; Balakrishnan, N.

2017-04-01

Quantum reactive scattering calculations for the H/D + HD(v = 4 , j = 1 , 2) -> H/D + HD(v', j') and H + H2(v = 4 , j = 1 , 2) -> H + H2(v', j') exchange reactions are presented for the ground electronic state of H3. A numerically exact three-dimensional time-independent scattering method based on hyperspherical coordinates is used to compute rotationally resolved reaction cross sections and non-thermal rate coefficients for collision energies between 1 μK and 100 K . The geometric (Berry) phase associated with the D3h conical intersection in H3 is included using a U(1) vector (gauge) potential approach. It is shown that the geometric phase leads to a significant (up to three orders of magnitude) enhancement or suppression of the ultracold reaction rate coefficients depending upon whether the interference between the reaction pathways encircling the conical intersection is constructive or destructive. The nature of the interference is governed by a newly discovered mechanism which leads to an effective quantization of the ultracold scattering phase shifts. Interesting behavior due to rotational excitation of the HD and H2 is observed which might be exploited by experimentalists to control the reaction outcome. This work was supported in part by NSF Grant PHY-1505557 (N.B.) and ARO MURI Grant No. W911NF-12-1-0476 (N.B.), and DOE LDRD Grant No. 20170221ER (B.K.).

The proteome pattern cGvHD_MS14 allows early and accurate prediction of chronic GvHD after allogeneic stem cell transplantation.

PubMed

Weissinger, E M; Human, C; Metzger, J; Hambach, L; Wolf, D; Greinix, H T; Dickinson, A M; Mullen, W; Jonigk, D; Kuzmina, Z; Kreipe, H; Schweier, P; Böhm, O; Türüchanow, I; Ihlenburg-Schwarz, D; Raad, J; Durban, A; Schiemann, M; Könecke, C; Diedrich, H; Holler, E; Beutel, G; Krauter, J; Ganser, A; Stadler, M

2017-03-01

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) may be curative, but is associated with significant morbidity and mortality. Chronic graft-versus-host disease (cGvHD), characterized by inflammation and fibrosis of multiple target organs, considerably contributes to the morbidity and mortality even years after allo-HSCT. Diagnosis of cGvHD is based on clinical features and histology of biopsies. Here, we report the generation of a urinary cGvHD-specific proteome-pattern (cGvHD_MS14) established by capillary electrophoresis-mass spectrometry to predict onset and severity of cGvHD as an unbiased laboratory test. cGvHD_MS14 was evaluated on samples from 412 patients collected prospectively in four transplant centers. Sensitivity and specificity was 84 and 76% by cGvHD_MS14 classification. Sensitivity further increased to 93% by combination of cGvHD_MS14 with relevant clinical variables to a logistic regression model. cGvHD was predicted up to 55 days prior to clinical diagnosis. Acute GvHD is not recognized by cGvHD_MS14. cGvHD_MS14 consists of 14 differentially excreted peptides, six of those have been sequenced to date and are fragments from thymosin β-4, eukaryotic translation initiation factor 4γ2, fibrinogen β-chain or collagens. In conclusion, the cGvHD_MS14-pattern allows early, highly sensitive and specific prediction of cGvHD as an independent diagnostic criterion of clinical diagnosis potentially allowing early therapeutic intervention.

TWO SMALL PLANETS TRANSITING HD 3167

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

Vanderburg, Andrew; Bieryla, Allyson; Latham, David W.

2016-09-20

We report the discovery of two super-Earth-sized planets transiting the bright (V = 8.94, K = 7.07) nearby late G-dwarf HD 3167, using data collected by the K2 mission. The inner planet, HD 3167 b, has a radius of 1.6 R {sub ⊕} and an ultra-short orbital period of only 0.96 days. The outer planet, HD 3167 c, has a radius of 2.9 R {sub ⊕} and orbits its host star every 29.85 days. At a distance of just 45.8 ± 2.2 pc, HD 3167 is one of the closest and brightest stars hosting multiple transiting planets, making HD 3167more » b and c well suited for follow-up observations. The star is chromospherically inactive with low rotational line-broadening, ideal for radial velocity observations to measure the planets’ masses. The outer planet is large enough that it likely has a thick gaseous envelope that could be studied via transmission spectroscopy. Planets transiting bright, nearby stars like HD 3167 are valuable objects to study leading up to the launch of the James Webb Space Telescope .« less

Characterization of a putative grapevine Zn transporter, VvZIP3, suggests its involvement in early reproductive development in Vitis vinifera L

PubMed Central

2012-01-01

Background Zinc (Zn) deficiency is one of the most widespread mineral nutritional problems that affect normal development in plants. Because Zn cannot passively diffuse across cell membranes, it must be transported into intracellular compartments for all biological processes where Zn is required. Several members of the Zinc-regulated transporters, Iron-regulated transporter-like Protein (ZIP) gene family have been characterized in plants, and have shown to be involved in metal uptake and transport. This study describes the first putative Zn transporter in grapevine. Unravelling its function may explain an important symptom of Zn deficiency in grapevines, which is the production of clusters with fewer and usually smaller berries than normal. Results We identified and characterized a putative Zn transporter from berries of Vitis vinifera L., named VvZIP3. Compared to other members of the ZIP family identified in the Vitis vinifera L. genome, VvZIP3 is mainly expressed in reproductive tissue - specifically in developing flowers - which correlates with the high Zn accumulation in these organs. Contrary to this, the low expression of VvZIP3 in parthenocarpic berries shows a relationship with the lower Zn accumulation in this tissue than in normal seeded berries where its expression is induced by Zn. The predicted protein sequence indicates strong similarity with several members of the ZIP family from Arabidopsis thaliana and other species. Moreover, VvZIP3 complemented the growth defect of a yeast Zn-uptake mutant, ZHY3, and is localized in the plasma membrane of plant cells, suggesting that VvZIP3 has the function of a Zn uptake transporter. Conclusions Our results suggest that VvZIP3 encodes a putative plasma membrane Zn transporter protein member of the ZIP gene family that might play a role in Zn uptake and distribution during the early reproductive development in Vitis vinifera L., indicating that the availability of this micronutrient may be relevant for

Characterization of a putative grapevine Zn transporter, VvZIP3, suggests its involvement in early reproductive development in Vitis vinifera L.

PubMed

Gainza-Cortés, Felipe; Pérez-Dïaz, Ricardo; Pérez-Castro, Ramón; Tapia, Jaime; Casaretto, José A; González, Sebastián; Peña-Cortés, Hugo; Ruiz-Lara, Simón; González, Enrique

2012-07-23

Zinc (Zn) deficiency is one of the most widespread mineral nutritional problems that affect normal development in plants. Because Zn cannot passively diffuse across cell membranes, it must be transported into intracellular compartments for all biological processes where Zn is required. Several members of the Zinc-regulated transporters, Iron-regulated transporter-like Protein (ZIP) gene family have been characterized in plants, and have shown to be involved in metal uptake and transport. This study describes the first putative Zn transporter in grapevine. Unravelling its function may explain an important symptom of Zn deficiency in grapevines, which is the production of clusters with fewer and usually smaller berries than normal. We identified and characterized a putative Zn transporter from berries of Vitis vinifera L., named VvZIP3. Compared to other members of the ZIP family identified in the Vitis vinifera L. genome, VvZIP3 is mainly expressed in reproductive tissue - specifically in developing flowers - which correlates with the high Zn accumulation in these organs. Contrary to this, the low expression of VvZIP3 in parthenocarpic berries shows a relationship with the lower Zn accumulation in this tissue than in normal seeded berries where its expression is induced by Zn. The predicted protein sequence indicates strong similarity with several members of the ZIP family from Arabidopsis thaliana and other species. Moreover, VvZIP3 complemented the growth defect of a yeast Zn-uptake mutant, ZHY3, and is localized in the plasma membrane of plant cells, suggesting that VvZIP3 has the function of a Zn uptake transporter. Our results suggest that VvZIP3 encodes a putative plasma membrane Zn transporter protein member of the ZIP gene family that might play a role in Zn uptake and distribution during the early reproductive development in Vitis vinifera L., indicating that the availability of this micronutrient may be relevant for reproductive development.

Study of Pulsations in the Atmosphere of the roAp star HD 137949

NASA Astrophysics Data System (ADS)

Sachkov, M.; Hareter, M.; Ryabchikova, T.; Wade, G.; Kochukhov, O.; Weiss, W. W.

The roAp star HD 137949 (33 Lib) shows the most complex pulsational behaviour among all roAp stars. Mkrtichian et al. (2003) found nearly anti-phase pulsations of Nd II and Nd III lines, which they attribute to the presence of a pulsation node high in the atmosphere of HD 137949. This was confirmed by Kurtz at al. (2005), who also find that in some REE lines the main frequency, corresponding to 8.27 min, and its harmonic have almost equal RV amplitudes. Based on high accuracy observations Ryabchikova et al. (2007a) studied pulsational characteristics of the HD 137949 atmosphere in detail. In general, spectroscopy provides 3D resolution of modes and allows to search for the photometrically undetectable frequencies. The high-accuracy space photometry provides very high-precision measurements of detected pulsation frequencies and enables an accurate phasing of multi-site spectroscopic data. A combination of simultaneous spectroscopy and photometry represents the most sophisticated asteroseismic dataset for any roAp star. In 2009 the star HD 137949 became a target of an intense observing campaign that combined ground-based spectroscopy with space photometry, obtained with the MOST satellite. We collected 780 spectra using the ESPaDOnS spectrograph mounted on the 3.6 m CFHT telescope; 374 spectra were obtained with the FIES spectrograph mounted on the 2.56-m NOT to perform the time-resolved spectroscopy of HD 137949. In addition, we used 111 UVES spectra (2004) from the ESO archive to check the mode stability. The frequency analysis of the new radial velocity (RV) measurements confirmed the previously reported frequency pattern (two frequencies and the first harmonic of the main frequency), and revealed an additional frequency at 1.991 mHz. The new frequency solution fits perfectly the RV variations from the 2004 and 2009 observational sets providing a strong support for the p-mode stability in the roAp star HD 137949 for at least 5 years.

Multiple PAR and E4BP4 bZIP transcription factors in zebrafish: diverse spatial and temporal expression patterns.

PubMed

Ben-Moshe, Zohar; Vatine, Gad; Alon, Shahar; Tovin, Adi; Mracek, Philipp; Foulkes, Nicholas S; Gothilf, Yoav

2010-09-01

Circadian rhythms of physiology and behavior are generated by an autonomous circadian oscillator that is synchronized daily with the environment, mainly by light input. The PAR subfamily of transcriptional activators and the related E4BP4 repressor belonging to the basic leucine zipper (bZIP) family are clock-controlled genes that are suggested to mediate downstream circadian clock processes and to feedback onto the core oscillator. Here, the authors report the characterization of these genes in the zebrafish, an increasingly important model in the field of chronobiology. Five novel PAR and six novel e4bp4 zebrafish homolog genes were identified using bioinformatic tools and their coding sequences were cloned. Based on their evolutionary relationships, these genes were annotated as ztef2, zhlf1 and zhlf2, zdbp1 and zdbp2, and ze4bp4-1 to -6. The spatial and temporal mRNA expression pattern of each of these factors was characterized in zebrafish embryos in the context of a functional circadian clock and regulation by light. Nine of the factors exhibited augmented and rhythmic expression in the pineal gland, a central clock organ in zebrafish. Moreover, these genes were found to be regulated, to variable extents, by the circadian clock and/or by light. Differential expression patterns of multiple paralogs in zebrafish suggest multiple roles for these factors within the vertebrate circadian clock. This study, in the genetically accessible zebrafish model, lays the foundation for further research regarding the involvement and specific roles of PAR and E4BP4 transcription factors in the vertebrate circadian clock mechanism.

IRT-ZIP Modeling for Multivariate Zero-Inflated Count Data

ERIC Educational Resources Information Center

Wang, Lijuan

2010-01-01

This study introduces an item response theory-zero-inflated Poisson (IRT-ZIP) model to investigate psychometric properties of multiple items and predict individuals' latent trait scores for multivariate zero-inflated count data. In the model, two link functions are used to capture two processes of the zero-inflated count data. Item parameters are…

Investigation of Super*Zip separation joint

NASA Technical Reports Server (NTRS)

Bement, Laurence J.; Schimmel, Morry L.

1988-01-01

An investigation to determine the most likely cause of two failures of five tests on 79 inch diameter Lockheed Super*Zip spacecraft separation joints being used for the development of a Shuttle/Centaur propulsion system. This joint utilizes an explosively expanded tube to fracture surrounding prenotched aluminum plates to achieve planar separation. A test method was developed and more than 300 tests firings were made to provide an understanding of severance mechanisms and the functional performance effects of system variables. An approach for defining functional margin was developed, and specific recommendations were made for improving existing and future systems.

ZIP2DL: An Elastic-Plastic, Large-Rotation Finite-Element Stress Analysis and Crack-Growth Simulation Program

NASA Technical Reports Server (NTRS)

Deng, Xiaomin; Newman, James C., Jr.

1997-01-01

ZIP2DL is a two-dimensional, elastic-plastic finte element program for stress analysis and crack growth simulations, developed for the NASA Langley Research Center. It has many of the salient features of the ZIP2D program. For example, ZIP2DL contains five material models (linearly elastic, elastic-perfectly plastic, power-law hardening, linear hardening, and multi-linear hardening models), and it can simulate mixed-mode crack growth for prescribed crack growth paths under plane stress, plane strain and mixed state of stress conditions. Further, as an extension of ZIP2D, it also includes a number of new capabilities. The large-deformation kinematics in ZIP2DL will allow it to handle elastic problems with large strains and large rotations, and elastic-plastic problems with small strains and large rotations. Loading conditions in terms of surface traction, concentrated load, and nodal displacement can be applied with a default linear time dependence or they can be programmed according to a user-defined time dependence through a user subroutine. The restart capability of ZIP2DL will make it possible to stop the execution of the program at any time, analyze the results and/or modify execution options and resume and continue the execution of the program. This report includes three sectons: a theoretical manual section, a user manual section, and an example manual secton. In the theoretical secton, the mathematics behind the various aspects of the program are concisely outlined. In the user manual section, a line-by-line explanation of the input data is given. In the example manual secton, three types of examples are presented to demonstrate the accuracy and illustrate the use of this program.

Generation of a Slc39a8 hypomorph mouse: Markedly decreased ZIP8 Zn{sup 2+}/(HCO{sub 3}{sup -}){sub 2} transporter expression

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

Wang, Bin; He, Lei; Dong, Hongbin

2011-07-01

Highlights: {yields} The mouse Slc39a8 gene encodes the ZIP8 transporter. {yields} ZIP8 functions endogenously as a electroneutral Zn{sup 2+}/(HCO{sub 3}{sup -}){sub 2} symporter. {yields} A Slc39a8(neo/neo) hypomorph mouse, due to retention of the neo mini-gene, has been created. {yields} ZIP8 expression in utero is {approx}90% decreased in all tissues examined. {yields} This mouse model will be useful for studying developmental and in utero physiological functions of ZIP8. -- Abstract: Previously this laboratory has identified the mouse Slc39a8 gene encoding the ZIP8 transporter, important in cadmium uptake. ZIP8 functions endogenously as a electroneutral Zn{sup 2+}/(HCO{sub 3}{sup -}){sub 2} symporter, moving bothmore » ions into the cell. The overall physiological importance of ZIP8 remains unclear. Herein we describe generation of a mouse line carrying the Slc39a8(neo) allele, containing the Frt-flanked neomycin-resistance (neo) mini-cassette in intron 3 and loxP sites in introns 3 and 6. Cre recombinase functions correctly in Escherichia coli and in adeno-Cre-infected mouse fetal fibroblasts, but does not function in the intact mouse for reasons not clear. Slc39a8(neo) is a hypomorphic allele, because Slc39a8(neo/neo) homozygotes exhibit dramatically decreased ZIP8 expression in embryo, fetus, and visceral yolk sac - in comparison to their littermate wild-type controls. This ZIP8 hypomorph will be instrumental in studying developmental and in utero physiological functions of the ZIP8 transporter.« less

Characterization of a highly toxic strain of Bacillus thuringiensis serovar kurstaki very similar to the HD-73 strain.

PubMed

Reinoso-Pozo, Yaritza; Del Rincón-Castro, Ma Cristina; Ibarra, Jorge E

2016-09-01

The LBIT-1200 strain of Bacillus thuringiensis was recently isolated from soil, and showed a 6.4 and 9.5 increase in toxicity, against Manduca sexta and Trichoplusia ni, respectively, compared to HD-73. However, LBIT-1200 was still highly similar to HD-73, including the production of bipyramidal crystals containing only one protein of ∼130 000 kDa, its flagellin gene sequence related to the kurstaki serotype, plasmid and RepPCR patterns similar to HD-73, no production of β-exotoxin and no presence of VIP genes. Sequencing of its cry gene showed the presence of a cry1Ac-type gene with four amino acid differences, including two amino acid replacements in domain III, compared to Cry1Ac1, which may explain its higher toxicity. In conclusion, the LBIT-1200 strain is a variant of the HD-73 strain but shows a much higher toxicity, which makes this new strain an important candidate to be developed as a bioinsecticide, once it passes other tests, throughout its biotechnological development. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Fundamental parameters of massive stars in multiple systems: The cases of HD 17505A and HD 206267A

NASA Astrophysics Data System (ADS)

Raucq, F.; Rauw, G.; Mahy, L.; Simón-Díaz, S.

2018-06-01

Context. Many massive stars are part of binary or higher multiplicity systems. The present work focusses on two higher multiplicity systems: HD 17505A and HD 206267A. Aims: Determining the fundamental parameters of the components of the inner binary of these systems is mandatory to quantify the impact of binary or triple interactions on their evolution. Methods: We analysed high-resolution optical spectra to determine new orbital solutions of the inner binary systems. After subtracting the spectrum of the tertiary component, a spectral disentangling code was applied to reconstruct the individual spectra of the primary and secondary. We then analysed these spectra with the non-LTE model atmosphere code CMFGEN to establish the stellar parameters and the CNO abundances of these stars. Results: The inner binaries of these systems have eccentric orbits with e 0.13 despite their relatively short orbital periods of 8.6 and 3.7 days for HD 17505Aa and HD 206267Aa, respectively. Slight modifications of the CNO abundances are found in both components of each system. The components of HD 17505Aa are both well inside their Roche lobe, whilst the primary of HD 206267Aa nearly fills its Roche lobe around periastron passage. Whilst the rotation of the primary of HD 206267Aa is in pseudo-synchronization with the orbital motion, the secondary displays a rotation rate that is higher. Conclusions: The CNO abundances and properties of HD 17505Aa can be explained by single star evolutionary models accounting for the effects of rotation, suggesting that this system has not yet experienced binary interaction. The properties of HD 206267Aa suggest that some intermittent binary interaction might have taken place during periastron passages, but is apparently not operating anymore. Based on observations collected with the TIGRE telescope (La Luz, Mexico), the 1.93 m telescope at Observatoire de Haute Provence (France), the Nordic Optical Telescope at the Observatorio del Roque de los

X-Raying the Coronae of HD 155555

NASA Technical Reports Server (NTRS)

Lalitha, S.; Singh, K.P.; Drake, S. A.; Kashyap, V.

2015-01-01

We present an analysis of the high-resolution Chandra observation of the multiple system, HD 155555 (an RS CVn type binary system, HD 155555 AB, and its spatially resolved low-mass companion HD 155555 C). This is an intriguing system which shows properties of both an active pre-main sequence star and a synchronised (main sequence) binary. We obtain the emission measure distribution, temperature structures, plasma densities, and abundances of this system and compare them with the coronal properties of other young/active stars. HD 155555 AB and HD 155555 C produce copious X-ray emission with log L(sub x) of 30.54 and 29.30, respectively, in the 0.3-6.0 kiloelectronvolt energy band. The light curves of individual stars show variability on timescales of few minutes to hours. We analyse the dispersed spectra and reconstruct the emission measure distribution using spectral line analysis. The resulting elemental abundances exhibit inverse first ionisation potential effect in both cases. An analysis of He-like triplets yields a range of coronal electron densities 1010 - 1013 per cubic centimeter. Since HD 155555 AB is classified both as an RS CVn and a PMS star, we compare our results with those of other slightly older active main-sequence stars and T Tauri stars, which indicates that the coronal properties of HD 155555 AB closely resemble that of an older RS CVn binary rather than a younger PMS star. Our results also suggests that the properties of HD 155555 C is very similar to those of other active M dwarfs.

On the physical association of the peculiar emission: Line stars HD 122669 and HD 122691

NASA Technical Reports Server (NTRS)

Garrison, R. F.; Hiltner, W. A.; Sanduleak, N.

1975-01-01

Spectroscopic and photometric observations indicate a physical association between the peculiar early-type emission-line stars HD 122669 and HD 122691. The latter has undergone a drastic change in the strength of its emission lines during the past twenty years. There is some indication that both stars vary with shorter time scales.

Behavior of Abundances in Chemically Peculiar Dwarf and Subgiant A-Type Stars: HD 23193 and HD 170920

NASA Astrophysics Data System (ADS)

Kılıçoğlu, Tolgahan; Çalışkan, Şeyma; Ünal, Kübraözge

2018-01-01

To understand the origin of the abundance peculiarities of non-magnetic A-type stars, we present the first detailed chemical abundance analysis of a metallic line star HD 23193 (A2m) and an A-type subgiant HD 170920 (A5), which could have been a HgMn star on the main sequence. Our analysis is based on medium (R ∼ 14,000) and high (R ∼ 40,000) resolution spectroscopic data of the stars. The abundances of 18 elements are derived: C, O, Na, Mg, Al, Si, S, Ca, Sc, Ti, Cr, Mn, Fe, Ni, Zn, Sr, Y, and Ba. The masses of HD 23193 and HD 170920 are estimated from evolutionary tracks as 2.3 ± 0.1 M ⊙ and 2.9 ± 0.1 M ⊙. The ages are found to be 635 ± 33 Myr for HD 23193 and 480 ± 50 Myr for HD 170920 using isochrones. The abundance pattern of HD 23193 shows deviations from solar values in the iron-peak elements and indicates remarkable overabundances of Sr (1.16), Y (1.03), and Ba (1.24) with respect to the solar abundances. We compare the derived abundances of this moderately rotating (v\\sin i =37.5 km s‑1) Am star to the theoretical chemical evolution models including rotational mixing. The theoretically predicted abundances resemble our derived abundance pattern, except for a few elements (Si and Cr). For HD 170920, we find nearly solar abundances, except for C (‑0.43), S (0.16), Ti (0.15), Ni (0.16), Zn (0.41), Y (0.57), and Ba (0.97). Its low rotational velocity (v\\sin i=14.5 km s‑1), reduced carbon abundance, and enhanced heavy element abundances suggest that the star is most likely an evolved HgMn star. Based on observations made at the TÜBITAK National Observatory (Program ID 14BRTT150–671), and the Ankara University Observatory, Turkey.

bZIP17 regulates the expression of genes related to seed storage and germination, reducing seed susceptibility to osmotic stress.

PubMed

Cifuentes-Esquivel, Nicolás; Celiz-Balboa, Jonathan; Henriquez-Valencia, Carlos; Mitina, Irina; Arraño-Salinas, Paulina; Moreno, Adrián A; Meneses, Claudio; Blanco-Herrera, Francisca; Orellana, Ariel

2018-04-25

Low temperatures, salinity, and drought cause significant crop losses. These conditions involve osmotic stress, triggering transcriptional remodeling, and consequently, the restitution of cellular homeostasis and growth recovery. Protein transcription factors regulate target genes, thereby mediating plant responses to stress. bZIP17 is a transcription factor involved in cellular responses to salinity and the unfolded protein response. Because salinity can also produce osmotic stress, the role of bZIP17 in response to osmotic stress was assessed. Mannitol treatments induced the transcript accumulation and protein processing of bZIP17. Transcriptomic analyses showed that several genes associated with seed storage and germination showed lower expression in bzip17 mutants than in wild-type plants. Interestingly, bZIP17 transcript was more abundant in seeds, and germination analyses revealed that wild-type plants germinated later than bzip17 mutants in the presence of mannitol, but no effects were observed when the seeds were exposed to ABA. Finally, the transcript levels of bZIP17 target genes that control seed storage and germination were assessed in seeds exposed to mannitol treatments, which showed lower expression levels in bzip17 mutants compared to the wild-type seeds. These results suggest that bZIP17 plays a role in osmotic stress, acting as a negative regulator of germination through the regulation of genes involved in seed storage and germination. © 2018 Wiley Periodicals, Inc.

The normal huntington disease (HD) allele, or a closely linked gene, influences age at onset of HD

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

Farrer, L.A.; Cupples, L.A.; Conneally, P.M.

1993-07-01

The authors evaluated the hypothesis that Huntington disease (HD) is influenced by the normal HD allele by comparing transmission patterns of genetically linked markers at the D4S10 locus in the normal parent against age at onset in the affected offspring. Analysis of information from 21 sibships in 14 kindreds showed a significant tendency for sibs who have similar onset ages to share the same D4S10 allele from the normal parent. Affected sibs who inherited different D4S10 alleles from the normal parent tended to have more variable ages at onset. These findings suggest that the expression of HD is modulated bymore » the normal HD allele or by a closely linked locus. 38 refs., 2 figs., 1 tab.« less

Effect of reagent rotation on the integral cross-sections and isotopic branching of the reactions H - + HD and D - + HD

NASA Astrophysics Data System (ADS)

Zhang, Wei; Liu, Yufang; He, Xiaohu

2010-04-01

A quasi-classical trajectory (QCT) method has been used to calculate integral reaction cross-section for H - + HD and D - + HD. The influence of rotation of the reagent on the integral reaction cross-section and the product branching ratios of the title reactions are discussed. The results indicate that the reactive cross-section of H(D) - + HD → HH(D) + D - decreases with an increase of the j for E tran ⩽ 1.5 eV. The results also show that the reactive cross-section of D(H) - + HD → DD(H) + H - decreases with an increase of the j for E tran ⩽ 1.0 eV and that the integral cross-sections of title reactions are sensitive to the reagent rotation.

ZIP8 expression in human proximal tubule cells, human urothelial cells transformed by Cd+2 and As+3 and in specimens of normal human urothelium and urothelial cancer

PubMed Central

2012-01-01

Background ZIP8 functions endogenously as a Zn+2/HCO3- symporter that can also bring cadmium (Cd+2) into the cell. It has also been proposed that ZIP8 participates in Cd-induced testicular necrosis and renal disease. In this study real-time PCR, western analysis, immunostaining and fluorescent localization were used to define the expression of ZIP8 in human kidney, cultured human proximal tubule (HPT) cells, normal and malignant human urothelium and Cd+2 and arsenite (As+3) transformed urothelial cells. Results It was shown that in the renal system both the non-glycosylated and glycosylated form of ZIP8 was expressed in the proximal tubule cells with localization of ZIP8 to the cytoplasm and cell membrane; findings in line with previous studies on ZIP8. The studies in the bladder were the first to show that ZIP8 was expressed in normal urothelium and that ZIP8 could be localized to the paranuclear region. Studies in the UROtsa cell line confirmed a paranuclear localization of ZIP8, however addition of growth medium to the cells increased the expression of the protein in the UROtsa cells. In archival human samples of the normal urothelium, the expression of ZIP8 was variable in intensity whereas in urothelial cancers ZIP8 was expressed in 13 of 14 samples, with one high grade invasive urothelial cancer showing no expression. The expression of ZIP8 was similar in the Cd+2 and As+3 transformed UROtsa cell lines and their tumor transplants. Conclusion This is the first study which shows that ZIP8 is expressed in the normal urothelium and in bladder cancer. In addition the normal UROtsa cell line and its transformed counterparts show similar expression of ZIP8 compared to the normal urothelium and the urothelial cancers suggesting that the UROtsa cell line could serve as a model system to study the expression of ZIP8 in bladder disease. PMID:22550998

Validity and reliability of the Fitbit Zip as a measure of preschool children’s step count

PubMed Central

Sharp, Catherine A; Mackintosh, Kelly A; Erjavec, Mihela; Pascoe, Duncan M; Horne, Pauline J

2017-01-01

Objectives Validation of physical activity measurement tools is essential to determine the relationship between physical activity and health in preschool children, but research to date has not focused on this priority. The aims of this study were to ascertain inter-rater reliability of observer step count, and interdevice reliability and validity of Fitbit Zip accelerometer step counts in preschool children. Methods Fifty-six children aged 3–4 years (29 girls) recruited from 10 nurseries in North Wales, UK, wore two Fitbit Zip accelerometers while performing a timed walking task in their childcare settings. Accelerometers were worn in secure pockets inside a custom-made tabard. Video recordings enabled two observers to independently code the number of steps performed in 3 min by each child during the walking task. Intraclass correlations (ICCs), concordance correlation coefficients, Bland-Altman plots and absolute per cent error were calculated to assess the reliability and validity of the consumer-grade device. Results An excellent ICC was found between the two observer codings (ICC=1.00) and the two Fitbit Zips (ICC=0.91). Concordance between the Fitbit Zips and observer counts was also high (r=0.77), with an acceptable absolute per cent error (6%–7%). Bland-Altman analyses identified a bias for Fitbit 1 of 22.8±19.1 steps with limits of agreement between −14.7 and 60.2 steps, and a bias for Fitbit 2 of 25.2±23.2 steps with limits of agreement between −20.2 and 70.5 steps. Conclusions Fitbit Zip accelerometers are a reliable and valid method of recording preschool children’s step count in a childcare setting. PMID:29081984

Expression Patterns and Correlations with Metabolic Markers of Zinc Transporters ZIP14 and ZNT1 in Obesity and Polycystic Ovary Syndrome

PubMed Central

Maxel, Trine; Svendsen, Pernille Fog; Smidt, Kamille; Lauridsen, Jesper Krogh; Brock, Birgitte; Pedersen, Steen Bønlykke; Rungby, Jørgen; Larsen, Agnete

2017-01-01

Polycystic ovary syndrome (PCOS) is associated with infertility, increased androgen levels, and insulin resistance. In adipose tissue, zinc facilitates insulin signaling. Circulating zinc levels are altered in obesity, diabetes, and PCOS; and zinc supplementation can ameliorate metabolic disturbances in PCOS. In adipose tissue, expression of zinc influx transporter ZIP14 varies with body mass index (BMI), clinical markers of metabolic syndrome, and peroxisome proliferator-activated receptor gamma (PPARG). In this study, we investigated expression levels of ZIP14 and PPARG in subcutaneous adipose tissue of 36 PCOS women (17 lean and 19 obese women) compared with 23 healthy controls (7 lean and 16 obese women). Further, expression levels of zinc transporter ZIP9, a recently identified androgen receptor, and zinc efflux transporter ZNT1 were investigated, alongside lipid profile and markers of glucose metabolism [insulin degrading enzyme, retinol-binding protein 4 (RBP4), and glucose transporter 4 (GLUT4)]. We find that ZIP14 expression is reduced in obesity and positively correlates with PPARG expression, which is downregulated with increasing BMI. ZNT1 is upregulated in obesity, and both ZIP14 and ZNT1 expression significantly correlates with clinical markers of altered glucose metabolism. In addition, RBP4 and GLUT4 associate with obesity, but an association with PCOS as such was present only for PPARG and RBP4. ZIP14 and ZNT1 does not relate to clinical androgen status and ZIP9 is unaffected by all parameters investigated. In conclusion, our findings support the existence of a zinc dyshomeostasis in adipose tissue in metabolic disturbances including PCOS-related obesity. PMID:28303117

Requirement of Zinc Transporter SLC39A7/ZIP7 for Dermal Development to Fine-Tune Endoplasmic Reticulum Function by Regulating Protein Disulfide Isomerase.

PubMed

Bin, Bum-Ho; Bhin, Jinhyuk; Seo, Juyeon; Kim, Se-Young; Lee, Eunyoung; Park, Kyuhee; Choi, Dong-Hwa; Takagishi, Teruhisa; Hara, Takafumi; Hwang, Daehee; Koseki, Haruhiko; Asada, Yoshinobu; Shimoda, Shinji; Mishima, Kenji; Fukada, Toshiyuki

2017-08-01

Skin is the first area that manifests zinc deficiency. However, the molecular mechanisms by which zinc homeostasis affects skin development remain largely unknown. Here, we show that zinc-regulation transporter-/iron-regulation transporter-like protein 7 (ZIP7) localized to the endoplasmic reticulum plays critical roles in connective tissue development. Mice lacking the Slc39a7/Zip7 gene in collagen 1-expressing tissue exhibited dermal dysplasia. Ablation of ZIP7 in mesenchymal stem cells inhibited cell proliferation thereby preventing proper dermis formation, indicating that ZIP7 is required for dermal development. We also found that mesenchymal stem cells lacking ZIP7 accumulated zinc in the endoplasmic reticulum, which triggered zinc-dependent aggregation and inhibition of protein disulfide isomerase, leading to endoplasmic reticulum dysfunction. These results suggest that ZIP7 is necessary for endoplasmic reticulum function in mesenchymal stem cells and, as such, is essential for dermal development. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Characterization of microRNAs Expressed during Secondary Wall Biosynthesis in Acacia mangium

PubMed Central

Ong, Seong Siang; Wickneswari, Ratnam

2012-01-01

MicroRNAs (miRNAs) play critical regulatory roles by acting as sequence specific guide during secondary wall formation in woody and non-woody species. Although thousands of plant miRNAs have been sequenced, there is no comprehensive view of miRNA mediated gene regulatory network to provide profound biological insights into the regulation of xylem development. Herein, we report the involvement of six highly conserved amg-miRNA families (amg-miR166, amg-miR172, amg-miR168, amg-miR159, amg-miR394, and amg-miR156) as the potential regulatory sequences of secondary cell wall biosynthesis. Within this highly conserved amg-miRNA family, only amg-miR166 exhibited strong differences in expression between phloem and xylem tissue. The functional characterization of amg-miR166 targets in various tissues revealed three groups of HD-ZIP III: ATHB8, ATHB15, and REVOLUTA which play pivotal roles in xylem development. Although these three groups vary in their functions, -psRNA target analysis indicated that miRNA target sequences of the nine different members of HD-ZIP III are always conserved. We found that precursor structures of amg-miR166 undergo exhaustive sequence variation even within members of the same family. Gene expression analysis showed three key lignin pathway genes: C4H, CAD, and CCoAOMT were upregulated in compression wood where a cascade of miRNAs was downregulated. This study offers a comprehensive analysis on the involvement of highly conserved miRNAs implicated in the secondary wall formation of woody plants. PMID:23251324

A Hamiltonian replica exchange method for building protein-protein interfaces applied to a leucine zipper

NASA Astrophysics Data System (ADS)

Cukier, Robert I.

2011-01-01

Leucine zippers consist of alpha helical monomers dimerized (or oligomerized) into alpha superhelical structures known as coiled coils. Forming the correct interface of a dimer from its monomers requires an exploration of configuration space focused on the side chains of one monomer that must interdigitate with sites on the other monomer. The aim of this work is to generate good interfaces in short simulations starting from separated monomers. Methods are developed to accomplish this goal based on an extension of a previously introduced [Su and Cukier, J. Phys. Chem. B 113, 9595, (2009)] Hamiltonian temperature replica exchange method (HTREM), which scales the Hamiltonian in both potential and kinetic energies that was used for the simulation of dimer melting curves. The new method, HTREM_MS (MS designates mean square), focused on interface formation, adds restraints to the Hamiltonians for all but the physical system, which is characterized by the normal molecular dynamics force field at the desired temperature. The restraints in the nonphysical systems serve to prevent the monomers from separating too far, and have the dual aims of enhancing the sampling of close in configurations and breaking unwanted correlations in the restrained systems. The method is applied to a 31-residue truncation of the 33-residue leucine zipper (GCN4-p1) of the yeast transcriptional activator GCN4. The monomers are initially separated by a distance that is beyond their capture length. HTREM simulations show that the monomers oscillate between dimerlike and monomerlike configurations, but do not form a stable interface. HTREM_MS simulations result in the dimer interface being faithfully reconstructed on a 2 ns time scale. A small number of systems (one physical and two restrained with modified potentials and higher effective temperatures) are sufficient. An in silico mutant that should not dimerize because it lacks charged residues that provide electrostatic stabilization of the dimer

Manifestations of poverty and birthrates among young teenagers in California zip code areas.

PubMed

Kirby, D; Coyle, K; Gould, J B

2001-01-01

Given that many communities are implementing community-wide initiatives to reduce teenage pregnancy or childbearing, it is important to understand the effects of a community's characteristics on adolescent birthrates. Data from the 1990 census and from California birth certificates were obtained for zip codes in California. Regression analyses were conducted on data from zip code areas with at least 200 females aged 15-17 between 1991 and 1996, to predict the effects of race and ethnicity marital status, education, employment, income and poverty, and housing on birthrates among young teenagers. In bivariate analyses, the proportion of families living below poverty level within a zip code was highly related to the birthrate among young teenagers in that zip code (r=.80, p<.001). In multivariate analyses, which controlled for some of the correlates of family poverty level, the proportion of families living below poverty level remained by far the most important predictor of the birthrate among young teenagers (b=1.54), followed by the proportion of adults aged 25 or older who have a college education (b=-0.80). Race and ethnicity were only weakly related to birthrate. In all three racial and ethnic groups, poverty and education were significantly related to birthrate, but the effect of college education was greater among Hispanics (b=-2.98) than among either non-Hispanic whites (b=-0.53) or blacks (b=-1.12). Male employment and unemployment and female unemployment were highly related to the birthrate among young teenagers in some racial or ethnic groups, but not in others. Multiple manifestations of poverty, including poverty itself, low levels of education and employment, and high levels of unemployment, may have a large impact upon birthrates among young teenagers. Addressing some of these issues could substantially reduce childbearing among young adolescents.

Geometric phase effects in the ultracold D + HD $$ \\rightarrow $$ D + HD and D + HD $$\\leftrightarrow $$ H + D 2 reactions

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

Kendrick, Brian Kent; Hazra, Jisha; Balakrishnan, Naduvaluth

The results of accurate quantum reactive scattering calculations for the D + HD(v = 4, j = 0)more » $$\\to $$ D + HD($$v^{\\prime} $$, $$j^{\\prime} $$), D + HD(v = 4, j = 0) $$\\to $$ H + D2($$v^{\\prime} $$, $$j^{\\prime} $$) and H + D2(v = 4, j = 0) $$\\to $$ D + HD($$v^{\\prime} $$, $$j^{\\prime} $$) reactions are presented for collision energies between $$1\\,\\mu {\\rm{K}}$$ and $$100\\,{\\rm{K}}$$. The ab initio BKMP2 PES for the ground electronic state of H3 is used and all values of total angular momentum between $J=0-4$ are included. The general vector potential approach is used to include the geometric phase. The rotationally resolved, vibrationally resolved, and total reaction rate coefficients are reported as a function of collision energy. Rotationally resolved differential cross sections are also reported as a function of collision energy and scattering angle. Large geometric phase effects appear in the ultracold reaction rate coefficients which result in a significant enhancement or suppression of the rate coefficient (up to 3 orders of magnitude) relative to calculations which ignore the geometric phase. The results are interpreted using a new quantum interference mechanism which is unique to ultracold collisions. Significant effects of the geometric phase also appear in the rotationally resolved differential cross sections which lead to a very different oscillatory structure in both energy and scattering angle. Several shape resonances occur in the 1–$$10\\,{\\rm{K}}$$ energy range and the geometric phase is shown to significantly alter the predicted resonance spectrum. The geometric phase effects and ultracold rate coefficients depend sensitively on the nuclear spin. Furthermore, experimentalists may be able to control the reaction by the selection of a particular nuclear spin state.« less

Geometric phase effects in the ultracold D + HD $$ \\rightarrow $$ D + HD and D + HD $$\\leftrightarrow $$ H + D 2 reactions

DOE PAGES

Kendrick, Brian Kent; Hazra, Jisha; Balakrishnan, Naduvaluth

2016-12-15

The results of accurate quantum reactive scattering calculations for the D + HD(v = 4, j = 0)more » $$\\to $$ D + HD($$v^{\\prime} $$, $$j^{\\prime} $$), D + HD(v = 4, j = 0) $$\\to $$ H + D2($$v^{\\prime} $$, $$j^{\\prime} $$) and H + D2(v = 4, j = 0) $$\\to $$ D + HD($$v^{\\prime} $$, $$j^{\\prime} $$) reactions are presented for collision energies between $$1\\,\\mu {\\rm{K}}$$ and $$100\\,{\\rm{K}}$$. The ab initio BKMP2 PES for the ground electronic state of H3 is used and all values of total angular momentum between $J=0-4$ are included. The general vector potential approach is used to include the geometric phase. The rotationally resolved, vibrationally resolved, and total reaction rate coefficients are reported as a function of collision energy. Rotationally resolved differential cross sections are also reported as a function of collision energy and scattering angle. Large geometric phase effects appear in the ultracold reaction rate coefficients which result in a significant enhancement or suppression of the rate coefficient (up to 3 orders of magnitude) relative to calculations which ignore the geometric phase. The results are interpreted using a new quantum interference mechanism which is unique to ultracold collisions. Significant effects of the geometric phase also appear in the rotationally resolved differential cross sections which lead to a very different oscillatory structure in both energy and scattering angle. Several shape resonances occur in the 1–$$10\\,{\\rm{K}}$$ energy range and the geometric phase is shown to significantly alter the predicted resonance spectrum. The geometric phase effects and ultracold rate coefficients depend sensitively on the nuclear spin. Furthermore, experimentalists may be able to control the reaction by the selection of a particular nuclear spin state.« less

An epidemiologic study of index and family infectious mononucleosis and adult Hodgkin's disease (HD): evidence for a specific association with EBV+ve HD in young adults.

PubMed

Alexander, Freda E; Lawrence, Davia J; Freeland, June; Krajewski, Andrew S; Angus, Brian; Taylor, G Malcolm; Jarrett, Ruth F

2003-11-01

Infectious mononucleosis (IM) is an established risk factor for Hodgkin's disease (HD). A substantial minority (33%) of cases of HD have Epstein-Barr virus (EBV) DNA within the malignant cells (are EBV+ve). It is unclear whether risk after IM applies specifically to EBV+ve HD. We report the results of a population-based case-control study of HD in adults (n = 408 cases of classical HD, 513 controls) aged 16-74 years; the case series included 113 EBV+ve and 243 EBV+ve HD. Analyses compared total HD, EBV+ve HD and EBV-ve HD with the controls and EBV+ve HD with EBV-ve HD cases using, mainly, logistic regression. Regression analyses were adjusted for gender, age-group and socioeconomic status, and were performed for the whole age range and separately for young (< 35 years) and old adults (> or = 35 years); formal tests of effect modification by age were included. For the young adults, reported IM in index or relative was strongly and significantly associated with EBV+ve HD when compared to controls (odds ratio [OR] = 2.94, 95% confidence interval [CI]: 1.08-7.98 and OR = 5.22, 95% CI: 2.15-12.68, respectively). These results may be interpreted as indications that late first exposure to EBV increases risk of HD, especially in young adults; this applies primarily to EBV+ve HD. Copyright 2003 Wiley-Liss, Inc.

Intercellular communication in plants: evidence for two rapidly transmitted systemic signals generated in response to electromagnetic field stimulation in tomato.

PubMed

Beaubois, Elisabeth; Girard, Sebastien; Lallechere, Sebastien; Davies, Eric; Paladian, Françoise; Bonnet, Pierre; Ledoigt, Gerard; Vian, Alain

2007-07-01

Exposing all of a wild-type tomato plant to electromagnetic radiation evoked rapid and substantial accumulation of basic leucine-zipper transcription factor (bZIP) mRNA in the terminal leaf (#4) with kinetics very similar to that seen in response to wounding, while in the abscisic acid (ABA) mutant (Sitiens), the response was more rapid, but transient. Submitting just the oldest leaf (#1) of a wild-type plant to irradiation evoked bZIP mRNA accumulation both locally in the exposed leaf and systemically in the unexposed (distant) leaf #4, although systemic accumulation was delayed somewhat. Accumulation of Pin2 mRNA was less than bZIP in both the exposed and distant leaves in wild type, but there was no delay in the systemic response. In Sitiens, bZIP mRNA accumulation was far less than in wild type in both local and distant leaves, while Pin2 mRNA accumulation was stronger in the exposed leaf, but totally prevented in the systemic leaf. In the jasmonic acid (JA) mutant (JL-5) and in wild-type plants treated with the ABA biosynthesis inhibitor, naproxen, responses were similar to those in the ABA mutant, while treatment of the exposed leaf with calcium antagonists totally abolished both local and systemic increases in bZIP transcript accumulation.

New ALMA Images of the HD 32297 and HD 61005 Debris Disks

NASA Astrophysics Data System (ADS)

MacGregor, Meredith Ann; Weinberger, Alycia; Wilner, David; Hughes, A. Meredith; debes, John Henry; Redfield, Seth; Donaldson, Jessica; Nesvold, Erika; Schneider, Glenn; Currie, Thayne; Roberge, Aki; Rodriguez, David

2018-01-01

HD 61005 (G-type star, “The Moth") and HD 32297 (A-type star) host two of the most iconic debris disks. Scattered light images show that both disks are nearly edge-on with dramatic swept-back wings of dust. Previous studies have proposed a range of mechanisms to explain this distinctive morphology including interactions with the interstellar medium, secular perturbations of grains by low-density, neutral interstellar gas, and gravitational interactions with an inclined, eccentric companion. We present new observations from the Atacama Large Millimeter/submillimeter Array (ALMA) at 1.3 mm that provide the highest resolution images at millimeter wavelengths to date of both systems. Observations at millimeter wavelengths are especially critical to our understanding of the physical mechanisms shaping the structure of these disks, since the large grains that dominate emission at these wavelengths are less affected by stellar radiation and winds and more reliably trace the underlying planetesimal distribution. We fit models directly to the observed visibilities within a Markov Chain Monte Carlo (MCMC) framework to characterize the continuum emission and place constraints on the structure of these unique debris disks. Our new ALMA images reveal that despite differences in spectral type, both systems are best described by a two-component structure with (1) a parent body belt, and (2) an outer halo aligned with the scattered light disk. Such halos have typically been assumed to be composed of small grains visible in scattered light, so these images are some of the first observational evidence that larger grains may also populate extended halos. In addition, we detect significant 12CO gas emission from HD 32297, and determine a robust upper limit for HD 61005.

HD 104860 and HD 192758: Two Debris Disks Newly Imaged in Scattered Light with the Hubble Space Telescope

NASA Astrophysics Data System (ADS)

Choquet, É.; Bryden, G.; Perrin, M. D.; Soummer, R.; Augereau, J.-C.; Chen, C. H.; Debes, J. H.; Gofas-Salas, E.; Hagan, J. B.; Hines, D. C.; Mawet, D.; Morales, F.; Pueyo, L.; Rajan, A.; Ren, B.; Schneider, G.; Stark, C. C.; Wolff, S.

2018-02-01

We present the first scattered-light images of two debris disks around the F8 star HD 104860 and the F0V star HD 192758, respectively ∼45 and ∼67 pc away. We detected these systems in the F110W and F160W filters through our reanalysis of archival Hubble Space Telescope (HST) NICMOS data with modern starlight-subtraction techniques. Our image of HD 104860 confirms the morphology previously observed by Herschel in thermal emission with a well-defined ring at a radius of ∼114 au inclined by ∼58°. Although the outer edge profile is consistent with dynamical evolution models, the sharp inner edge suggests sculpting by unseen perturbers. Our images of HD 192758 reveal a disk at radius ∼95 au inclined by ∼59°, never resolved so far. These disks have low scattering albedos of 10% and 13%, respectively, inconsistent with water ice grain compositions. They are reminiscent of several other disks with similar inclination and scattering albedos: Fomalhaut, HD 92945, HD 202628, and HD 207129. They are also very distinct from brighter disks in the same inclination bin, which point to different compositions between these two populations. Varying scattering albedo values can be explained by different grain porosities, chemical compositions, or grain size distributions, which may indicate distinct formation mechanisms or dynamical processes at work in these systems. Finally, these faint disks with large infrared excesses may be representative of an underlying population of systems with low albedo values. Searches with more sensitive instruments on HST or on the James Webb Space Telescope and using state-of-the art starlight-subtraction methods may help discover more of such faint systems.

Enhanced Functional Genomic Screening Identifies Novel Mediators of Dual Leucine Zipper Kinase-Dependent Injury Signaling in Neurons.

PubMed

Welsbie, Derek S; Mitchell, Katherine L; Jaskula-Ranga, Vinod; Sluch, Valentin M; Yang, Zhiyong; Kim, Jessica; Buehler, Eugen; Patel, Amit; Martin, Scott E; Zhang, Ping-Wu; Ge, Yan; Duan, Yukan; Fuller, John; Kim, Byung-Jin; Hamed, Eman; Chamling, Xitiz; Lei, Lei; Fraser, Iain D C; Ronai, Ze'ev A; Berlinicke, Cynthia A; Zack, Donald J

2017-06-21

Dual leucine zipper kinase (DLK) has been implicated in cell death signaling secondary to axonal damage in retinal ganglion cells (RGCs) and other neurons. To better understand the pathway through which DLK acts, we developed enhanced functional genomic screens in primary RGCs, including use of arrayed, whole-genome, small interfering RNA libraries. Explaining why DLK inhibition is only partially protective, we identify leucine zipper kinase (LZK) as cooperating with DLK to activate downstream signaling and cell death in RGCs, including in a mouse model of optic nerve injury, and show that the same pathway is active in human stem cell-derived RGCs. Moreover, we identify four transcription factors, JUN, activating transcription factor 2 (ATF2), myocyte-specific enhancer factor 2A (MEF2A), and SRY-Box 11 (SOX11), as being the major downstream mediators through which DLK/LZK activation leads to RGC cell death. Increased understanding of the DLK pathway has implications for understanding and treating neurodegenerative diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

Properties of Zip4 accumulation during zinc deficiency and its usefulness to evaluate zinc status: a study of the effects of zinc deficiency during lactation.

PubMed

Hashimoto, Ayako; Nakagawa, Miki; Tsujimura, Natsuki; Miyazaki, Shiho; Kizu, Kumiko; Goto, Tomoko; Komatsu, Yusuke; Matsunaga, Ayu; Shirakawa, Hitoshi; Narita, Hiroshi; Kambe, Taiho; Komai, Michio

2016-03-01

Systemic and cellular zinc homeostasis is elaborately controlled by ZIP and ZnT zinc transporters. Therefore, detailed characterization of their expression properties is of importance. Of these transporter proteins, Zip4 functions as the primarily important transporter to control systemic zinc homeostasis because of its indispensable function of zinc absorption in the small intestine. In this study, we closely investigated Zip4 protein accumulation in the rat small intestine in response to zinc status using an anti-Zip4 monoclonal antibody that we generated and contrasted this with the zinc-responsive activity of the membrane-bound alkaline phosphatase (ALP). We found that Zip4 accumulation is more rapid in response to zinc deficiency than previously thought. Accumulation increased in the jejunum as early as 1 day following a zinc-deficient diet. In the small intestine, Zip4 protein expression was higher in the jejunum than in the duodenum and was accompanied by reduction of ALP activity, suggesting that the jejunum can become zinc deficient more easily. Furthermore, by monitoring Zip4 accumulation levels and ALP activity in the duodenum and jejunum, we reasserted that zinc deficiency during lactation may transiently alter plasma glucose levels in the offspring in a sex-specific manner, without affecting homeostatic control of zinc metabolism. This confirms that zinc nutrition during lactation is extremely important for the health of the offspring. These results reveal that rapid Zip4 accumulation provides a significant conceptual advance in understanding the molecular basis of systemic zinc homeostatic control, and that properties of Zip4 protein accumulation are useful to evaluate zinc status closely. Copyright © 2016 the American Physiological Society.

Pepper CabZIP63 acts as a positive regulator during Ralstonia solanacearum or high temperature-high humidity challenge in a positive feedback loop with CaWRKY40.

PubMed

Shen, Lei; Liu, Zhiqin; Yang, Sheng; Yang, Tong; Liang, Jiaqi; Wen, Jiayu; Liu, Yanyan; Li, Jiazhi; Shi, Lanping; Tang, Qian; Shi, Wei; Hu, Jiong; Liu, Cailing; Zhang, Yangwen; Lin, Wei; Wang, Rongzhang; Yu, Huanxin; Mou, Shaoliang; Hussain, Ansar; Cheng, Wei; Cai, Hanyang; He, Li; Guan, Deyi; Wu, Yang; He, Shuilin

2016-04-01

CaWRKY40 is known to act as a positive regulator in the response of pepper (Capsicum annuum) to Ralstonia solanacearum inoculation (RSI) or high temperature-high humidity (HTHH), but the underlying mechanism remains elusive. Herein, we report that CabZIP63, a pepper bZIP family member, participates in this process by regulating the expression of CaWRKY40. CabZIP63 was found to localize in the nuclei, be up-regulated by RSI or HTHH, bind to promoters of both CabZIP63(pCabZIP63) and CaWRKY40(pCaWRKY40), and activate pCabZIP63- and pCaWRKY40-driven β-glucuronidase expression in a C- or G-box-dependent manner. Silencing of CabZIP63 by virus-induced gene silencing (VIGS) in pepper plants significantly attenuated their resistance to RSI and tolerance to HTHH, accompanied by down-regulation of immunity- or thermotolerance-associated CaPR1, CaNPR1, CaDEF1, and CaHSP24. Hypersensitive response-mediated cell death and expression of the tested immunity- and thermotolerance-associated marker genes were induced by transient overexpression (TOE) of CabZIP63, but decreased by that of CabZIP63-SRDX. Additionally, binding of CabZIP63 to pCaWRKY40 was up-regulated by RSI or HTHH, and the transcript level of CaWRKY40 and binding of CaWRKY40 to the promoters of CaPR1, CaNPR1, CaDEF1 and CaHSP24 were up-regulated by TOE of CabZIP63. On the other hand, CabZIP63 was also up-regulated transcriptionally by TOE of CaWRKY40. The data suggest collectively that CabZIP63 directly or indirectly regulates the expression of CaWRKY40 at both the transcriptional and post-transcriptional level, forming a positive feedback loop with CaWRKY40 during pepper's response to RSI or HTHH. Altogether, our data will help to elucidate the underlying mechanism of crosstalk between pepper's response to RSI and HTHH. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Overexpression of OsTF1L, a rice HD-Zip transcription factor, promotes lignin biosynthesis and stomatal closure that improves drought tolerance.

PubMed

Bang, Seung Woon; Lee, Dong-Keun; Jung, Harin; Chung, Pil Joong; Kim, Youn Shic; Choi, Yang Do; Suh, Joo-Won; Kim, Ju-Kon

2018-05-21

Drought stress seriously impacts on plant development and productivity. Improvement of drought tolerance without yield penalty is a great challenge in crop biotechnology. Here, we report that the rice (Oryza sativa) homeodomain-leucine zipper transcription factor gene, OsTF1L (Oryza sativa transcription factor 1-like), is a key regulator of drought tolerance mechanisms. Overexpression of the OsTF1L in rice significantly increased drought tolerance at the vegetative stages of growth and promoted both effective photosynthesis and a reduction in the water loss rate under drought conditions. Importantly, the OsTF1L overexpressing plants showed a higher drought tolerance at the reproductive stage of growth with a higher grain yield than non-transgenic controls under field-drought conditions. Genome-wide analysis of OsTF1L overexpression plants revealed up-regulation of drought-inducible, stomatal movement and lignin biosynthetic genes. Overexpression of OsTF1L promoted accumulation of lignin in shoots, whereas the RNAi lines showed opposite patterns of lignin accumulation. OsTF1L is mainly expressed in outer cell layers including the epidermis, and the vasculature of the shoots, which coincides with areas of lignification. In addition, OsTF1L overexpression enhances stomatal closure under drought conditions resulted in drought tolerance. More importantly, OsTF1L directly bound to the promoters of lignin biosynthesis and drought-related genes involving poxN/PRX38, Nodulin protein, DHHC4, CASPL5B1 and AAA-type ATPase. Collectively, our results provide a new insight into the role of OsTF1L in enhancing drought tolerance through lignin biosynthesis and stomatal closure in rice. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Does it really matter that people zip through ads? Testing the effectiveness of simultaneous presentation advertising in an IDTV environment.

PubMed

Nam, Yoonjae; Kwon, Kyonghee H; Lee, Sungjoon

2010-04-01

In an IDTV environment, which facilitates self-scheduling, skipping advertisements by zipping is an emerging ad-avoidance behavior. This study explores whether an alternative ad format, called simultaneous presentation advertising (SPA), may overcome the limitations of classical sequential advertising (CSA) in controlling zipping behavior and increasing the effectiveness of ads. The experiment revealed that SPA is more effective than CSA in reducing zipping and increasing recall, but SPA was more intrusive and produced a negative product image. There was no difference regarding cognitive avoidance. This work discusses the implications of these findings in the interactive media environment.

Copernicus observations of distant unreddened stars. I. Line of sight to MU Colombae and HD 28497

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

Shull, J.M.; York, D.G.

1977-02-01

Copernicus UV data on interstellar lines toward ..mu.. Col and HD 28497 are analyzed to study the abundances and physical conditions in the many components found in each line of sight. Despite low mean neutral hydrogen densities toward these stars, a substantial portion of the neutral gas is associated with dense condensations containing H/sub 2/. In several high-velocity components, Fe, Ca, and possibly Si appear to be nearer their cosmic abundances than is typical in interstellar gas; this effect may be related to the correlation of N (Ca II)/N (Na I) with cloud velocity, and suggests a grain-disruption model. Low-velocitymore » ionized gas with n/sub e/=0.1 to 0.3 cm/sup -3/ appears to be associated with an extended H II region near ..mu.. Col; ionized gas of similar density is seen at the same velocities as the four neutral components toward HD 28497. Si III absorption, with a wide profile at high negative velocities, unaccompanied by any detectable Si II, N II, or neutral gas, is reported in both stars. The observed Si III column densities and velocity fields may be explained by collisionally ionized gas at 30,000 to 100,000 K behind radiatively cooling strong shocks.« less

Computing travel time when the exact address is unknown: a comparison of point and polygon ZIP code approximation methods.

PubMed

Berke, Ethan M; Shi, Xun

2009-04-29

Travel time is an important metric of geographic access to health care. We compared strategies of estimating travel times when only subject ZIP code data were available. Using simulated data from New Hampshire and Arizona, we estimated travel times to nearest cancer centers by using: 1) geometric centroid of ZIP code polygons as origins, 2) population centroids as origin, 3) service area rings around each cancer center, assigning subjects to rings by assuming they are evenly distributed within their ZIP code, 4) service area rings around each center, assuming the subjects follow the population distribution within the ZIP code. We used travel times based on street addresses as true values to validate estimates. Population-based methods have smaller errors than geometry-based methods. Within categories (geometry or population), centroid and service area methods have similar errors. Errors are smaller in urban areas than in rural areas. Population-based methods are superior to the geometry-based methods, with the population centroid method appearing to be the best choice for estimating travel time. Estimates in rural areas are less reliable.

HD 47755, a new eclipsing binary

NASA Technical Reports Server (NTRS)

Koch, R. H.; Bradstreet, D. H.; Hrivnak, B. J.; Pfeiffer, R. J.; Perry, P. M.

1986-01-01

The IUE spectra of the close binary star HD 47755 have been examined in order to determine its geometry, chemical composition, and light curve. UBV fluxes in the spectra, when dereddened for E(B-V) = 0.09 yield an effective temperature of 16,500 K. The ratio of the mean radii of the stars is found to agree well with an old blueband spectrophotometric value. Eclipses in the binary have been observed and a complex green light curve is derived. It is suggested that the wind from at least one of the components of HD 47755 is the source of the complexity in the light curve. The geometry of the HD 47755 is compared to that of V 641 Mon, A definite cluster member of NGC 2264. The interstellar line spectrum is found to be similar to that of V 641 Mon and the column densities for a few interstellar ions are given in a table. Evaluation of the nonastrometric evidence indicates that HD 47755 is also a member of NGC 2264.

Hubble Space Telescope Observations of the HD 202628 Debris Disk

NASA Technical Reports Server (NTRS)

Krist, John E.; Stapelfeldt, Karl R.; Bryden, Geoffrey; Plavchan, Peter

2012-01-01

A ring-shaped debris disk around the G2V star HD 202628 (d = 24.4 pc) was imaged in scattered light at visible wavelengths using the coronagraphic mode of the Space Telescope Imaging Spectrograph on the Hubble Space Telescope. The ring is inclined by approx.64deg from face-on, based on the apparent major/minor axis ratio, with the major axis aligned along PA = 130deg. It has inner and outer radii (> 50% maximum surface brightness) of 139 AU and 193 AU in the northwest ansae and 161 AU and 223 AU in the southeast ((Delta)r/r approx. = 0.4). The maximum visible radial extent is approx. 254 AU. With a mean surface brightnesses of V approx. = 24 mag arcsec.(sup -2), this is the faintest debris disk observed to date in reflected light. The center of the ring appears offset from the star by approx.28 AU (deprojected). An ellipse fit to the inner edge has an eccentricity of 0.18 and a = 158 AU. This offset, along with the relatively sharp inner edge of the ring, suggests the influence of a planetary-mass companion. There is a strong similarity with the debris ring around Fomalhaut, though HD 202628 is a more mature star with an estimated age of about 2 Gyr. We also provide surface brightness limits for nine other stars in our study with strong Spitzer excesses around which no debris disks were detected in scattered light (HD 377, HD 7590, HD 38858, HD 45184, HD 73350, HD 135599, HD 145229, HD 187897, and HD 201219).

Hubble Space Telescope Observations of the HD 202628 Debris Disk

NASA Astrophysics Data System (ADS)

Krist, John E.; Stapelfeldt, Karl R.; Bryden, Geoffrey; Plavchan, Peter

2012-08-01

A ring-shaped debris disk around the G2V star HD 202628 (d = 24.4 pc) was imaged in scattered light at visible wavelengths using the coronagraphic mode of the Space Telescope Imaging Spectrograph on the Hubble Space Telescope. The ring is inclined by ~64° from face-on, based on the apparent major/minor axis ratio, with the major axis aligned along P.A. = 130°. It has inner and outer radii (>50% maximum surface brightness) of 139 AU and 193 AU in the northwest ansae and 161 AU and 223 AU in the southeast (Δr/r ≈ 0.4). The maximum visible radial extent is ~254 AU. With mean surface brightness of V ≈ 24 mag arcsec-2, this is the faintest debris disk observed to date in reflected light. The center of the ring appears offset from the star by ~28 AU (deprojected). An ellipse fit to the inner edge has an eccentricity of 0.18 and a = 158 AU. This offset, along with the relatively sharp inner edge of the ring, suggests the influence of a planetary-mass companion. There is a strong similarity with the debris ring around Fomalhaut, though HD 202628 is a more mature star with an estimated age of about 2 Gyr. We also provide surface brightness limits for nine other stars in our study with strong Spitzer excesses around which no debris disks were detected in scattered light (HD 377, HD 7590, HD 38858, HD 45184, HD 73350, HD 135599, HD 145229, HD 187897, and HD 201219).

A Comparison of Problem Behavior Profiles in Turkish Children with AD/HD and Non-AD/HD Children

ERIC Educational Resources Information Center

Ozdemir, Selda

2010-01-01

Introduction: There is an increasing number of studies describing the symptoms of ADHD among school-age children in western cultures. Yet, studies on children with ADHD living in non-western cultures are limited. Thus, the purpose of this study was to compare problem behavior profiles of Turkish children with AD/HD and non-AD/HD children. Method:…

Membrane androgen receptor characteristics of human ZIP9 (SLC39A) zinc transporter in prostate cancer cells: Androgen-specific activation and involvement of an inhibitory G protein in zinc and MAP kinase signaling.

PubMed

Thomas, Peter; Pang, Yefei; Dong, Jing

2017-05-15

Characteristics of novel human membrane androgen receptor (mAR), ZIP9 (SLC39A9), were investigated in ZIP9-transfected PC-3 cells (PC3-ZIP9). Ligand blot analysis showed plasma membrane [ 3 H]-T binding corresponds to the position of ZIP9 on Western blots which suggests ZIP9 can bind [ 3 H]-T alone, without a protein partner. Progesterone antagonized testosterone actions, blocking increases in zinc, Erk phosphorylation and apoptosis, further evidence that ZIP9 is specifically activated by androgens. Pre-treatment with GTPγS and pertussis toxin decreased plasma membrane [ 3 H]-T binding and blocked testosterone-induced increases in Erk phosphorylation and intracellular zinc, indicating ZIP9 is coupled to an inhibitory G protein (Gi) that mediates both MAP kinase and zinc signaling. Testosterone treatment of nuclei and mitochondria which express ZIP9 decreased their zinc contents, suggesting ZIP9 also regulates free zinc through releasing it from these intracellular organelles. The results show ZIP9 is a specific Gi coupled-mAR mediating testosterone-induced MAP kinase and zinc signaling in PC3-ZIP9 cells. Copyright © 2017 Elsevier B.V. All rights reserved.

VizieR Online Data Catalog: Solar-type stars from SDSS-III MARVELS. VI. HD 87646 (Ma+, 2016)

NASA Astrophysics Data System (ADS)

Ma, B.; Ge, J.; Wolszczan, A.; Muterspaugh, M. W.; Lee, B.; Henry, G. W.; Schneider, D. P.; Martin, E. L.; Niedzielski, A.; Xie, J.; Fleming, S. W.; Thomas, N.; Williamson, M.; Zhu, Z.; Agol, E.; Bizyaev, D.; da Costa, L. N.; Jiang, P.; Fiorenzano, A. F. M.; Hernandez, J. I. G.; Guo, P.; Grieves, N.; Li, R.; Liu, J.; Mahadevan, S.; Mazeh, T.; Nguyen, D. C.; Paegert, M.; Sithajan, S.; Stassun, K.; Thirupathi, S.; van Eyken, J. C.; Wan, X.; Wang, J.; Wisniewski, J. P.; Zhao, B.; Zucker, S.

2016-11-01

We have obtained a total of 16 observations of HD87646 using the W.M. Keck Exoplanet Tracker (KeckET) from 2006 December to 2007 June. The radial velocities obtained are listed in Table1. The KeckET instrument was constructed in 2005 August-2006 February with support from the Keck Foundation. It was coupled with a wide field Sloan Digital Sky Survey telescope (SDSS) and used for the pilot Multi-Object APO RV Exoplanet Large-Area Survey (MARVELS). This is the sixth paper in this series, examining the low-mass companions around solar-type stars from the SDSS-III MARVELS survey (Wisniewski et al. 2012, Cat. J/AJ/143/107; Fleming et al. 2012AJ....144...72F; Ma et al. 2013AJ....145...20M; Jiang et al. 2013AJ....146...65J; De Lee et al. 2013AJ....145..155D). The KeckET instrument consists of eight subsystems-a multi-object fiber feed, an iodine cell, a fixed-delay interferometer system, a slit, a collimator, a grating, a camera, and a 4k*4k CCD detector. In addition, it contains four auxiliary subsystems: the interferometer control, an instrument calibration system, a photon flux monitoring system, and a thermal probe and control system. The instrument is fed with 60 fibers with 200μm core diameters, which are coupled to 180μm core diameter short fibers from the SDSS telescope, corresponding to 3arcsec on the sky at f/5. The resolving power for the spectrograph is R=5100, and the wavelength coverage is ~900Å, centered at 5400Å. KeckET has one spectrograph and one 4k*4k CCD camera that captures one of the two interferometer outputs, and has a 5.5% detection efficiency from the telescope to the detector without the iodine cell under the typical APO seeing conditions (~1.5arcsec seeing). The CCD camera records fringing spectra from 59 objects in a single exposure. Subsequent observations were performed using the Exoplanet Tracker (ET) instrument at Kitt Peak National Observatory (KPNO). Initial follow-up was performed in 2007 November. Additional data points were

Oxidative stress upregulates zinc uptake activity via Zrt/Irt-like protein 1 (ZIP1) in cultured mouse astrocytes.

PubMed

Furuta, Takahiro; Ohshima, Chiaki; Matsumura, Mayu; Takebayashi, Naoto; Hirota, Emi; Mawaribuchi, Toshiki; Nishida, Kentaro; Nagasawa, Kazuki

2016-04-15

Zinc released from glutamatergic boutons and astrocytes acts as neuro- and glio-transmitters, and thus its extracellular level has to be strictly regulated. We previously revealed that uptake of zinc by astrocytes plays a critical role in its clearance, and zinc transporter Zrt/Irt-like protein 1 (ZIP1) is the molecule responsible for the uptake. However, it is unknown whether or not the functionality of the zinc clearance system is altered under oxidative stress-loaded conditions. Here, we characterized zinc uptake by oxidative stress-loaded astrocytes. Cultured mouse astrocytes were treated with hydrogen peroxide (H2O2) to load oxidative stress. Functional expression of ZIP1 in astrocytes was evaluated by means of (65)Zn uptake, Western blotting and immunocytochemical analysis. Treatment of astrocytes with 0.4mM H2O2 for 24h increased the expression levels of glial fibrillary acidic protein and 4-hydroxynonenal without significant decreases in their viability, indicating that induction of oxidative stress in astrocytes. Under oxidative stress-loaded conditions, astrocytes exhibited increased (65)Zn uptake activity, and the maximum uptake velocity for the uptake was significantly increased compared to that in the control group, while there was no change in the Michaelis constants, which were almost identical to that of mouse ZIP1. In the H2O2-treated astrocytes, the expression levels of ZIP1 were significantly increased in the cellular and plasma membrane fractions. It appears that under oxidative stress-loaded conditions, astrocytes exhibit increased zinc clearance activity and this is due, at least in part, to increased ZIP1 expression. Copyright © 2016 Elsevier Inc. All rights reserved.

The Star-grazing Bodies in the HD 172555 System

NASA Astrophysics Data System (ADS)

Grady, C. A.; Brown, Alexander; Welsh, Barry; Roberge, Aki; Kamp, Inga; Rivière Marichalar, P.

2018-06-01

Kiefer et al. reported the detection of infalling Ca II absorption in HD 172555, a member of the β Pictoris Moving Group (βPMG). We obtained HST Space Telescope Imaging Spectrograph and Cosmic Origins Spectrograph spectroscopy of this star at 2 epochs separated by a week, and we report the discovery of infalling gas in resonant transitions of Si III and IV, C II and IV, and neutral atomic oxygen. Variable absorption is seen in the C II transitions and is optically thick, with covering factors which range between 58% and 68%, similar to features seen in β Pictoris. The O I spectral profile resembles that of C II, showing a strong low-velocity absorption to +50 km s‑1 in the single spectral segment obtained during orbital night, as well as what may be higher-velocity absorption. Studies of the mid-IR spectrum of this system have suggested the presence of silica. The O I absorption differs from that seen in Si III, suggesting that the neutral atomic oxygen does not originate in SiO dissociation products but in a more volatile parent molecule such as CO.

Listeria monocytogenes infection of HD11, chicken macrophage-like cells.

PubMed

Jarvis, N A; Donaldson, J R; O'Bryan, C A; Ricke, S C; Crandall, P G

2017-04-01

Listeria monocytogenes can be carried by and infect poultry, although the clinical disease in birds is rare. Escape from macrophage phagocytosis is a key step in pathogenesis for L. monocytogenes. Therefore, we investigated the infection of the chicken macrophage-like cell line HD11 with 2 strains of L. monocytogenes EGD-e and Scott A. After infection, L. monocytogenes was quantified by spread plating and HD11 was quantified with trypan blue exclusion stain before enumeration. The standard macrophage killing protocols require washing the cell monolayers 3 times with PBS, which was found to negatively influence HD11 monolayers. Maximum bacterial densities within macrophages were not different between the 2 Listeria strains. HD11 required more than 11 h to effectively reduce intracellular L. monocytogenes Scott A, and Scott A was more susceptible to HD11 killing than EGD-e. It appears that Listeria infection initially causes attenuation of HD11 growth, and infected HD11 cells do not begin to lyse until at least 11 h post infection. These results suggest that there are subtle strain to strain differences in response to HD11 macrophage phagocytosis. The long lead-time required for HD11 to kill L. monocytogenes cells means that there is sufficient time available for chicken macrophages to circulate in the blood and transfer the intracellular Listeria to multiple tissues. © 2016 Poultry Science Association Inc.

Game-based combined cognitive and neurofeedback training using Focus Pocus reduces symptom severity in children with diagnosed AD/HD and subclinical AD/HD.

PubMed

Johnstone, Stuart J; Roodenrys, Steven J; Johnson, Kirsten; Bonfield, Rebecca; Bennett, Susan J

2017-06-01

Previous studies report reductions in symptom severity after combined working memory (WM) and inhibitory control (IC) training in children with AD/HD. Based on theoretical accounts of the role of arousal/attention modulation problems in AD/HD, the current study examined the efficacy of combined WM, IC, and neurofeedback training in children with AD/HD and subclinical AD/HD. Using a randomized waitlist control design, 85 children were randomly allocated to a training or waitlist condition and completed pre- and post-training assessments of overt behavior, trained and untrained cognitive task performance, and resting and task-related EEG activity. The training group completed twenty-five sessions of training using Focus Pocus software at home over a 7 to 8-week period. Trainees improved at the trained tasks, while enjoyment and engagement declined across sessions. After training, AD/HD symptom severity was reduced in the AD/HD and subclinical groups according to parents, and in the former group only according to blinded teachers and significant-others. There were minor improvements in two of six near-transfer tasks, and evidence of far-transfer of training effects in four of five far-transfer tasks. Frontal region changes indicated normalization of atypical EEG features with reduced delta and increased alpha activity. It is concluded that technology developments provide an interesting a vehicle for delivering interventions and that, while further research is needed, combined WM, IC, and neurofeedback training can reduce AD/HD symptom severity in children with AD/HD and may also be beneficial to children with subclinical AD/HD. Copyright © 2017 Elsevier B.V. All rights reserved.

How to Overcome Barriers and Establish a Successful Home HD Program

PubMed Central

Chan, Christopher; Blagg, Christopher; Lockridge, Robert; Golper, Thomas; Finkelstein, Fred; Shaffer, Rachel; Mehrotra, Rajnish

2012-01-01

Summary Home hemodialysis (HD) is an underused dialysis modality in the United States, even though it provides an efficient and probably cost-effective way to provide more frequent or longer dialysis. With the advent of newer home HD systems that are easier for patients to learn, use, and maintain, patient and provider interest in home HD is increasing. Although barriers for providers are similar to those for peritoneal dialysis, home HD requires more extensive patient training, nursing education, and infrastructure support in order to maintain a successful program. In addition, because many physicians and patients do not have experience with home HD, reluctance to start home HD programs is widespread. This in-depth review describes barriers to home HD, focusing on patients, individual physicians and practices, and dialysis facilities, and offers suggestions for how to overcome these barriers and establish a successful home HD program. PMID:23037981

77 FR 18716 - Transportation Security Administration Postal Zip Code Change; Technical Amendment

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-28

... organizational changes and it has no substantive effect on the public. DATES: Effective March 28, 2012. FOR... No. 1572-9] Transportation Security Administration Postal Zip Code Change; Technical Amendment AGENCY: Transportation Security Administration, DHS. ACTION: Final rule. SUMMARY: This rule is a technical change to...

Modeling hormonal control of cambium proliferation.

PubMed

Oles, Vladyslav; Panchenko, Alexander; Smertenko, Andrei

2017-01-01

Rise of atmospheric CO2 is one of the main causes of global warming. Catastrophic climate change can be avoided by reducing emissions and increasing sequestration of CO2. Trees are known to sequester CO2 during photosynthesis, and then store it as wood biomass. Thus, breeding of trees with higher wood yield would mitigate global warming as well as augment production of renewable construction materials, energy, and industrial feedstock. Wood is made of cellulose-rich xylem cells produced through proliferation of a specialized stem cell niche called cambium. Importance of cambium in xylem cells production makes it an ideal target for the tree breeding programs; however our knowledge about control of cambium proliferation remains limited. The morphology and regulation of cambium are different from those of stem cell niches that control axial growth. For this reason, translating the knowledge about axial growth to radial growth has limited use. Furthermore, genetic approaches cannot be easily applied because overlaying tissues conceal cambium from direct observation and complicate identification of mutants. To overcome the paucity of experimental tools in cambium biology, we constructed a Boolean network CARENET (CAmbium REgulation gene NETwork) for modelling cambium activity, which includes the key transcription factors WOX4 and HD-ZIP III as well as their potential regulators. Our simulations predict that: (1) auxin, cytokinin, gibberellin, and brassinosteroids act cooperatively in promoting transcription of WOX4 and HD-ZIP III; (2) auxin and cytokinin pathways negatively regulate each other; (3) hormonal pathways act redundantly in sustaining cambium activity; (4) individual cambium cells can have diverse molecular identities. CARENET can be extended to include components of other signalling pathways and be integrated with models of xylem and phloem differentiation. Such extended models would facilitate breeding trees with higher wood yield.

The perennial ryegrass GenomeZipper: targeted use of genome resources for comparative grass genomics.

PubMed

Pfeifer, Matthias; Martis, Mihaela; Asp, Torben; Mayer, Klaus F X; Lübberstedt, Thomas; Byrne, Stephen; Frei, Ursula; Studer, Bruno

2013-02-01

Whole-genome sequences established for model and major crop species constitute a key resource for advanced genomic research. For outbreeding forage and turf grass species like ryegrasses (Lolium spp.), such resources have yet to be developed. Here, we present a model of the perennial ryegrass (Lolium perenne) genome on the basis of conserved synteny to barley (Hordeum vulgare) and the model grass genome Brachypodium (Brachypodium distachyon) as well as rice (Oryza sativa) and sorghum (Sorghum bicolor). A transcriptome-based genetic linkage map of perennial ryegrass served as a scaffold to establish the chromosomal arrangement of syntenic genes from model grass species. This scaffold revealed a high degree of synteny and macrocollinearity and was then utilized to anchor a collection of perennial ryegrass genes in silico to their predicted genome positions. This resulted in the unambiguous assignment of 3,315 out of 8,876 previously unmapped genes to the respective chromosomes. In total, the GenomeZipper incorporates 4,035 conserved grass gene loci, which were used for the first genome-wide sequence divergence analysis between perennial ryegrass, barley, Brachypodium, rice, and sorghum. The perennial ryegrass GenomeZipper is an ordered, information-rich genome scaffold, facilitating map-based cloning and genome assembly in perennial ryegrass and closely related Poaceae species. It also represents a milestone in describing synteny between perennial ryegrass and fully sequenced model grass genomes, thereby increasing our understanding of genome organization and evolution in the most important temperate forage and turf grass species.

HD 202206: A Circumbinary Brown Dwarf System

NASA Astrophysics Data System (ADS)

Benedict, G. Fritz; Harrison, Thomas E.

2017-06-01

Using Hubble Space Telescope Fine Guidance Sensor astrometry and previously published radial velocity measures, we explore the exoplanetary system HD 202206. Our modeling results in a parallax, {π }{abs}=21.96+/- 0.12 milliseconds of arc, a mass for HD 202206 B of {{ M }}B={0.089}-0.006+0.007 {{ M }}⊙ , and a mass for HD 202206 c of {{ M }}c={17.9}-1.8+2.9 {{ M }}{Jup}. HD 202206 is a nearly face-on G + M binary orbited by a brown dwarf. The system architecture that we determine supports past assertions that stability requires a 5:1 mean motion resonance (we find a period ratio, {P}c/{P}B=4.92+/- 0.04) and coplanarity (we find a mutual inclination, {{Φ }}=6^\\circ +/- 2^\\circ ). Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555.

Absolute parameters of southern detached eclipsing binary: HD 53570

NASA Astrophysics Data System (ADS)

Sürgit, D.

2018-05-01

In this study, we conducted the first analysis of spectroscopic and photometric observations of the eclipsing binary star HD 53570. Spectroscopic observations of HD 53570 were made at the Sutherland Station of the South African Astronomical Observatory in 2013 and 2014. The radial velocities of the components were determined using the cross-correlation technique. The spectroscopic mass ratio obtained for the system was 1.13 ( ± 0.07). The All Sky Automated Survey V light curve of HD 53570 was analyzed using the Wilson-Devinney code combined with the Monte Carlo search method. The final model showed that HD 53570 has a detached configuration. The mass and radii of the primary and secondary components of HD 53570 were derived as 1.06 ( ± 0.07) M⊙, 1.20 ( ± 0.16) M⊙, and 1.42 ( ± 0.14) R⊙, 2.07 ( ± 0.16) R⊙, respectively. The distance of HD 53570 was computed as 248 ( ± 38) pc considering interstellar extinction. The evolutionary status of the component stars was also investigated using Geneva evolutionary models.

The IUE Mega Campaign. Modulated Structure in the Wind of HD 64760 (B0.5 Ib)

NASA Technical Reports Server (NTRS)

Prinja, Raman K.; Massa, Derck; Fullerton, Alexander W.

1995-01-01

We highlight systematic variability in the stellar wind of the early B type supergiant, HD 64760, whose UV line profiles were monitored for almost 16 days in 1995 January as part of the IUE 'MEGA Campaign.' The extensive coverage reveals a pattern of rapidly evolving discrete optical depth changes which typically migrate from approx. - 200 km/s to approx. -1500 km/s in less than 12 hr. These features coexist with more slowly evolving structures lasting several days. Time-series analysis of the Si(IV), Si(III), and N(V) profile variations presents a clear 1.2 day periodicity, which is a quarter of the estimated maximum rotation period of HD 64760. The line profile changes are consistent with an interpretation in terms of a set of corotating wind features which occult the stellar disk at least 3 times during the observing run. These data are combined with UV observations collected in 1993 March to argue in favor of rotationally modulated wind variations in HD 64760. The basic result of very regular, large-scale optical depth variations points to a 'clock' whose origin is on the stellar surface, rather than a mechanism that is entirely intrinsic to the stellar wind.

Medication Use in Early-HD Participants in Track-HD: an Investigation of its Effects on Clinical Performance.

PubMed

Keogh, Ruth; Frost, Chris; Owen, Gail; Daniel, Rhian M; Langbehn, Doug R; Leavitt, Blair; Durr, Alexandra; Roos, Raymund A C; Landwehrmeyer, G Bernhard; Reilmann, Ralf; Borowsky, Beth; Stout, Julie; Craufurd, David; Tabrizi, Sarah J

2016-01-11

 Insufficient evidence exists to guide the long-term pharmacological management of Huntington's disease (HD) although most current interventions rely on symptomatic management. The effect of many frontline treatments on potential endpoints for HD clinical trials remains unknown. Our objective was to investigate how therapies widely used to manage HD affect the symptom for which they are prescribed and other endpoints using data from TRACK-HD. We used longitudinal models to estimate effects of medication use on performance on tests of motor, cognitive and neuropsychiatric function using data from 123 TRACK-HD stage 1/2 participants across four study visits. Adjustment for confounding by prior medication use, prior clinical performance, concomitant use of other medications, and baseline variables (sex, disease group, age, CAG, study site, education) enabled a closer-to-causal interpretation of the associations. Adjusting for baseline variables only, medication use was typically associated with worse clinical performance, reflecting greater medication use in more advanced patients. After additional adjustment for longitudinal confounders such "inverse" associations were generally eliminated and in the expected directions: participants taking neuroleptics tended to have better motor performance, improved affect and poorer cognitive performance, and those taking SSRI/SNRIs had less apathy, less affect and better total behaviour scores. However, we uncovered few statistically significant associations. Limitations include sample size and unmeasured confounding. In conclusion, adjustment for confounding by prior measurements largely eliminated associations between medication use and poorer clinical performance from simple analyses. However, there was little convincing evidence of causal effects of medication on clinical performance and larger cohorts or trials are needed.

ABI-like transcription factor gene TaABL1 from wheat improves multiple abiotic stress tolerances in transgenic plants.

PubMed

Xu, Dong-Bei; Gao, Shi-Qing; Ma, You-Zhi; Xu, Zhao-Shi; Zhao, Chang-Ping; Tang, Yi-Miao; Li, Xue-Yin; Li, Lian-Cheng; Chen, Yao-Feng; Chen, Ming

2014-12-01

The phytohormone abscisic acid (ABA) plays crucial roles in adaptive responses of plants to abiotic stresses. ABA-responsive element binding proteins (AREBs) are basic leucine zipper transcription factors that regulate the expression of downstream genes containing ABA-responsive elements (ABREs) in promoter regions. A novel ABI-like (ABA-insensitive) transcription factor gene, named TaABL1, containing a conserved basic leucine zipper (bZIP) domain was cloned from wheat. Southern blotting showed that three copies were present in the wheat genome. Phylogenetic analyses indicated that TaABL1 belonged to the AREB subfamily of the bZIP transcription factor family and was most closely related to ZmABI5 in maize and OsAREB2 in rice. Expression of TaABL1 was highly induced in wheat roots, stems, and leaves by ABA, drought, high salt, and low temperature stresses. TaABL1 was localized inside the nuclei of transformed wheat mesophyll protoplast. Overexpression of TaABL1 enhanced responses of transgenic plants to ABA and hastened stomatal closure under stress, thereby improving tolerance to multiple abiotic stresses. Furthermore, overexpression of TaABL1 upregulated or downregulated the expression of some stress-related genes controlling stomatal closure in transgenic plants under ABA and drought stress conditions, suggesting that TaABL1 might be a valuable genetic resource for transgenic molecular breeding.

Arousal-state modulation in children with AD/HD.

PubMed

Benikos, Nicholas; Johnstone, Stuart J

2009-01-01

To investigate the effect of arousal-state modulation, via manipulation of stimulus event-rate, on response inhibition in children with Attention-Deficit/Hyperactivity disorder (AD/HD) using behavioural and ERP measures. Eighteen children with AD/HD, aged 7-14years, and 18 age-and sex-matched controls performed a cued visual Go/Nogo task (70% Go) with stimuli presented at fast, medium and slow event-rates. Task performance and ERPs to Warning, Go and Nogo stimuli, as well as preparation between the S1-S2 interval, were examined for group differences. AD/HD subjects displayed poorer response inhibition during the fast condition, accompanied by a reduced Nogo P3. Group differences during the fast rate extended to Warning cues, with the AD/HD group showing ERP evidence of atypical orienting/preparation, as indexed by the early and late CNV, and early sensory/attentive processing prior to S2. Although deficient response inhibition has been proposed as the core deficit in AD/HD, the results of the present study highlight the key role of energetic factors. Furthermore, group differences found to cues suggest that this effect extends to the processing of task-irrelevant stimuli. This was the first ERP Go/Nogo task investigation using three event-rates, and the results support the theory that state factors may contribute to response inhibition deficits in AD/HD.

The basic leucine zipper domain of c-Jun functions in transcriptional activation through interaction with the N terminus of human TATA-binding protein-associated factor-1 (human TAF(II)250).

PubMed

Lively, Tricia N; Nguyen, Tuan N; Galasinski, Shelly K; Goodrich, James A

2004-06-18

We previously reported that c-Jun binds directly to the N-terminal 163 amino acids of Homo sapiens TATA-binding protein-associated factor-1 (hsTAF1), causing a derepression of transcription factor IID (TFIID)-driven transcription (Lively, T. N., Ferguson, H. A., Galasinski, S. K., Seto, A. G., and Goodrich, J. A. (2001) J. Biol. Chem. 276, 25582-25588). This region of hsTAF1 binds TATA-binding protein to repress TFIID DNA binding and transcription. Here we show that the basic leucine zipper domain of c-Jun, which allows for DNA binding and homodimerization, is necessary and sufficient for interaction with hsTAF1. Interestingly, the isolated basic leucine zipper domain of c-Jun was able to derepress TFIID-directed basal transcription in vitro. Moreover, when the N-terminal region of hsTAF1 was added to in vitro transcription reactions and overexpressed in cells, it blocked c-Jun activation. c-Fos, another basic leucine zipper protein, did not interact with hsTAF1, but c-Fos/c-Jun heterodimers did bind the N terminus of hsTAF1. Our studies show that, in addition to dimerization and DNA binding, the well characterized basic leucine zipper domain of c-Jun functions in transcriptional activation by binding to the N terminus of hsTAF1 to derepress transcription.

The Discovery of HD 37605c and a Dispositive Null Detection of Transits of HD 37605b

NASA Astrophysics Data System (ADS)

Wang, Xuesong, Sharon; Wright, Jason T.; Cochran, William; Kane, Stephen R.; Henry, Gregory W.; Payne, Matthew J.; Endl, Michael; MacQueen, Phillip J.; Valenti, Jeff A.; Antoci, Victoria; Dragomir, Diana; Matthews, Jaymie M.; Howard, Andrew W.; Marcy, Geoffrey W.; Isaacson, Howard; Ford, Eric B.; Mahadevan, Suvrath; von Braun, Kaspar

2012-12-01

We report the radial velocity discovery of a second planetary mass companion to the K0 V star HD 37605, which was already known to host an eccentric, P ~ 55 days Jovian planet, HD 37605b. This second planet, HD 37605c, has a period of ~7.5 years with a low eccentricity and an Msin i of ~3.4 M Jup. Our discovery was made with the nearly 8 years of radial velocity follow-up at the Hobby-Eberly Telescope and Keck Observatory, including observations made as part of the Transit Ephemeris Refinement and Monitoring Survey effort to provide precise ephemerides to long-period planets for transit follow-up. With a total of 137 radial velocity observations covering almost 8 years, we provide a good orbital solution of the HD 37605 system, and a precise transit ephemeris for HD 37605b. Our dynamic analysis reveals very minimal planet-planet interaction and an insignificant transit time variation. Using the predicted ephemeris, we performed a transit search for HD 37605b with the photometric data taken by the T12 0.8 m Automatic Photoelectric Telescope (APT) and the MOST satellite. Though the APT photometry did not capture the transit window, it characterized the stellar activity of HD 37605, which is consistent of it being an old, inactive star, with a tentative rotation period of 57.67 days. The MOST photometry enabled us to report a dispositive null detection of a non-grazing transit for this planet. Within the predicted transit window, we exclude an edge-on predicted depth of 1.9% at the Gt10σ level, and exclude any transit with an impact parameter b > 0.951 at greater than 5σ. We present the BOOTTRAN package for calculating Keplerian orbital parameter uncertainties via bootstrapping. We made a comparison and found consistency between our orbital fit parameters calculated by the RVLIN package and error bars by BOOTTRAN with those produced by a Bayesian analysis using MCMC. Based on observations obtained with the Hobby-Eberly Telescope, which is a joint project of the

Asteroseismology of the δ Scuti star HD 50844

NASA Astrophysics Data System (ADS)

Chen, X. H.; Li, Y.; Lai, X. J.; Wu, T.

2016-09-01

Aims: We aim to probe the internal structure and investigate with asteroseismology for more detailed information on the δ Scuti star HD 50844. Methods: We analyse the observed frequencies of the δ Scuti star HD 50844 and search for possible multiplets, which are based on the rotational splitting law of g-mode. We tried to disentangle the frequency spectra of HD 50844 only by means of rotational splitting. We then compare these with theoretical pulsation modes, which correspond to stellar evolutionary models with various sets of initial metallicity and stellar mass, to find the best-fitting model. Results: There are three multiplets, including two complete triplets and one incomplete quintuplet, in which mode identifications for spherical harmonic degree l and azimuthal number m are unique. The corresponding rotational period of HD 50844 is found to be 2.44 days. The physical parameters of HD 50844 are well limited in a small region by three modes that have been identified as nonradial ones (f11, f22, and f29) and by the fundamental radial mode (f4). Our results show that the three nonradial modes (f11, f22, and f29) are all mixed modes, which mainly represent the property of the helium core. The fundamental radial mode (f4) mainly represents the property of the stellar envelope. To fit these four pulsation modes, both the helium core and the stellar envelope need to be matched to the actual structure of HD 50844. Finally, the mass of the helium core of HD 50844 is estimated to be 0.173 ± 0.004 M⊙ for the first time. The physical parameters of HD 50844 are determined to be M = 1.81 ± 0.01 M⊙, Z = 0.008 ± 0.001. Teff = 7508 ± 125 K, log g = 3.658 ± 0.004, R = 3.300 ± 0.023 R⊙, L = 30.98 ± 2.39 L⊙.

O-H bond oxidation by a monomeric Mn(III)-OMe complex.

PubMed

Wijeratne, Gayan B; Day, Victor W; Jackson, Timothy A

2015-02-21

Manganese-containing, mid-valent oxidants (Mn(III)-OR) that mediate proton-coupled electron-transfer (PCET) reactions are central to a variety of crucial enzymatic processes. The Mn-dependent enzyme lipoxygenase is such an example, where a Mn(III)-OH unit activates fatty acid substrates for peroxidation by an initial PCET. This present work describes the quantitative generation of the Mn(III)-OMe complex, [Mn(III)(OMe)(dpaq)](+) (dpaq = 2-[bis(pyridin-2-ylmethyl)]amino-N-quinolin-8-yl-acetamidate) via dioxygen activation by [Mn(II)(dpaq)](+) in methanol at 25 °C. The X-ray diffraction structure of [Mn(III)(OMe)(dpaq)](+) exhibits a Mn-OMe group, with a Mn-O distance of 1.825(4) Å, that is trans to the amide functionality of the dpaq ligand. The [Mn(III)(OMe)(dpaq)](+) complex is quite stable in solution, with a half-life of 26 days in MeCN at 25 °C. [Mn(III)(OMe)(dpaq)](+) can activate phenolic O-H bonds with bond dissociation free energies (BDFEs) of less than 79 kcal mol(-1) and reacts with the weak O-H bond of TEMPOH (TEMPOH = 2,2'-6,6'-tetramethylpiperidine-1-ol) with a hydrogen/deuterium kinetic isotope effect (H/D KIE) of 1.8 in MeCN at 25 °C. This isotope effect, together with other experimental evidence, is suggestive of a concerted proton-electron transfer (CPET) mechanism for O-H bond oxidation by [Mn(III)(OMe)(dpaq)](+). A kinetic and thermodynamic comparison of the O-H bond oxidation reactivity of [Mn(III)(OMe)(dpaq)](+) to other M(III)-OR oxidants is presented as an aid to gain more insight into the PCET reactivity of mid-valent oxidants. In contrast to high-valent counterparts, the limited examples of M(III)-OR oxidants exhibit smaller H/D KIEs and show weaker dependence of their oxidation rates on the driving force of the PCET reaction with O-H bonds.

Cellular Models: HD Patient-Derived Pluripotent Stem Cells.

PubMed

Geater, Charlene; Hernandez, Sarah; Thompson, Leslie; Mattis, Virginia B

2018-01-01

Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder caused by expanded polyglutamine (polyQ)-encoding repeats in the Huntingtin (HTT) gene. Traditionally, HD cellular models consisted of either patient cells not affected by disease or rodent neurons expressing expanded polyQ repeats in HTT. As these models can be limited in their disease manifestation or proper genetic context, respectively, human HD pluripotent stem cells (PSCs) are currently under investigation as a way to model disease in patient-derived neurons and other neural cell types. This chapter reviews embryonic stem cell (ESC) and induced pluripotent stem cell (iPSC) models of disease, including published differentiation paradigms for neurons and their associated phenotypes, as well as current challenges to the field such as validation of the PSCs and PSC-derived cells. Highlighted are potential future technical advances to HD PSC modeling, including transdifferentiation, complex in vitro multiorgan/system reconstruction, and personalized medicine. Using a human HD patient model of the central nervous system, hopefully one day researchers can tease out the consequences of mutant HTT (mHTT) expression on specific cell types within the brain in order to identify and test novel therapies for disease.

HD271791: dynamical versus binary-supernova ejection scenario

NASA Astrophysics Data System (ADS)

Gvaramadze, V. V.

2009-05-01

The atmosphere of the extremely high-velocity (530-920kms-1) early B-type star HD271791 is enriched in α-process elements, which suggests that this star is a former secondary component of a massive tight binary system and that its surface was polluted by the nucleosynthetic products after the primary star exploded in a supernova. It was proposed that the (asymmetric) supernova explosion unbind the system and that the secondary star (HD271791) was released at its orbital velocity in the direction of Galactic rotation. In this Letter, we show that to explain the Galactic rest-frame velocity of HD271791 within the framework of the binary-supernova scenario, the stellar remnant of the supernova explosion (a <~10Msolar black hole) should receive an unrealistically large kick velocity of >=750-1200kms-1. We therefore consider the binary-supernova scenario as highly unlikely and instead propose that HD271791 attained its peculiar velocity in the course of a strong dynamical three- or four-body encounter in the dense core of the parent star cluster. Our proposal implies that by the moment of encounter HD271791 was a member of a massive post-supernova binary.

Interleukin-1beta contributes via nitric oxide to the upregulation and functional activity of the zinc transporter Zip14 (Slc39a14) in murine hepatocytes.

PubMed

Lichten, Louis A; Liuzzi, Juan P; Cousins, Robert J

2009-04-01

Zinc metabolism during chronic disease is dysregulated by inflammatory cytokines. Experiments with IL-6 knockout mice show that LPS regulates expression of the zinc transporter, Zip14, by a mechanism that is partially independent of IL-6. The LPS-induced model of sepsis may occur by a mechanism signaled by nitric oxide (NO) as a secondary messenger. To address the hypothesis that NO can modulate Zip14 expression, we treated primary hepatocytes from wild-type mice with the NO donor S-nitroso N-acetyl penicillamine (SNAP). After treatment with SNAP, steady-state Zip14 mRNA levels displayed a maximal increase after 8 h and a concomitant increase in the transcriptional activity of the gene. Chromatin immunoprecipitation documented the kinetics of activator protein (AP)-1 and RNA polymerase II association with the Zip14 promoter after NO exposure, indicating a role of AP-1 in transcription of Zip14. We then stimulated the primary murine hepatocytes with IL-1beta, an LPS-induced proinflammatory cytokine and a potent activator of inducible NO synthase (iNOS) and NO production. In support of our hypothesis, IL-1beta treatment led to a threefold increase in Zip14 mRNA and enhanced zinc transport, as measured with a zinc fluorophore, in wild-type but not iNOS-/- hepatocytes. These data suggest that signaling pathways activated by NO are factors in the upregulation of Zip14, which in turn mediates hepatic zinc accumulation and hypozincemia during inflammation and sepsis.

“Addition” and “Subtraction”: Selectivity Design for Type II Maternal Embryonic Leucine Zipper Kinase Inhibitors

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

Chen, Xin; Giraldes, John; Sprague, Elizabeth R.

2017-02-17

While adding the structural features that are more favored by on-target activity is the more common strategy in selectivity optimization, the opposite strategy of subtracting the structural features that contribute more to off-target activity can also be very effective. Reported here is our successful effort of improving the kinase selectivity of type II maternal embryonic leucine zipper kinase inhibitors by applying these two complementary approaches together, which clearly demonstrates the powerful synergy between them.

The Age-Related Properties of the HD 98800 System

NASA Technical Reports Server (NTRS)

Soderblom, David R.; Henry, Todd J.; Shetrone, Matthew D.; Jones, Burton F.; Saar, Steven H.

1996-01-01

We present optical spectroscopy of the field K star system HD 98800, which has been found to have significant infrared emission from circumstellar material. The lithium abundances of the stars in HD 98800 are well above those of Pleiades of similar color, but activity levels and rotation in these stars are at or below Pleiades level. Thus, it is not yet possible to say whether HD 98800 is or is not a pre-main-sequence system, and it is possible that its components are on or near the zero-age main sequence. However, the two visible objects that make up HD 98800 both have high levels of lithium and activity, strongly suggesting that they are physically related to one another. As shown by Torres and coworkers, having these stars physically tied implies that their relative orbit is highly eccentric and highly inclined to our line of sight, and it also means that we are viewing the HD 98800 system at an unusual time in its orbit.

Far-ultraviolet energy distributions of the metal-poor A stars HD 109995 and HD 161817

NASA Technical Reports Server (NTRS)

Boehm-Vitense, E.

1981-01-01

Low-resolution IUE spectra at wavelengths between 1300 and 3400 A of the metal-poor stars HD 109995 (A1p) and HD 161817 (A4p) have been compared with model-atmosphere energy distributions computed by Kurucz (1979). Good overall agreement is found. Effective temperatures, metal abundances, and angular diameters could be determined. Assuming an absolute visual magnitude of 0.7, the previously determined gravity log = 3 yields masses of 0.5 solar masses for both stars. It is found that the theoretical UBV colors calculated earlier agree reaonably well with the ones observed for these stars.

Automatic anterior chamber angle assessment for HD-OCT images.

PubMed

Tian, Jing; Marziliano, Pina; Baskaran, Mani; Wong, Hong-Tym; Aung, Tin

2011-11-01

Angle-closure glaucoma is a major blinding eye disease and could be detected by measuring the anterior chamber angle in the human eyes. High-definition OCT (Cirrus HD-OCT) is an emerging noninvasive, high-speed, and high-resolution imaging modality for the anterior segment of the eye. Here, we propose a novel algorithm which automatically detects a new landmark, Schwalbe's line, and measures the anterior chamber angle in the HD-OCT images. The distortion caused by refraction is corrected by dewarping the HD-OCT images, and three biometric measurements are defined to quantitatively assess the anterior chamber angle. The proposed algorithm was tested on 40 HD-OCT images of the eye and provided accurate measurements in about 1 second.

Contribution to the search of binaries among Am stars. II. HD 81976 and HD 98880, double-lined spectroscopic binaries

NASA Astrophysics Data System (ADS)

Carquillat, J.-M.; Ginestet, N.; Prieur, J.-L.

2001-04-01

We present the results of the observations of two Am stars of eighth magnitude, the double-lined spectroscopic binaries HD 81976 and HD 98880, carried out with the CORAVEL instrument at the Observatoire de Haute-Provence in order to determine their orbital elements. We found 1) for HD 81976: P = 5.655750 days, T = 2449785.941 HJD, omega = 341.4deg, e = 0.061, K1 = 61.68 km s-1, K2 = 63.84 km s-1, V0 = 19.85 km s-1, a1 sin i = 4.788 Gm, a2 sin i = 4.956 Gm, M1 sin 3 i = 0.5875 Msun, M2 sin 3 i = 0.5676 Msun, and 2) for HD 98880: P = 14.20783 days, T0 = 2448682.883 HJD (ascending node), e = 0., K1 = 42.47 km s-1, K2 = 49.16 km s-1, V0 = 2.40 km s-1, a1 sin i = 8.298 Gm, a2 sin i = 9.604 Gm, M1 sin 3 i = 0.6091 Msun, M2 sin 3 i = 0.5262 Msun. The first of these two systems, HD 81976, is formed by two quasi-identical stars, and the Hipparcos data (MV, B-V) are consistent with late A stars in effective temperature; it is likely that the components rotate synchronised with the orbital motion. A third body may be present in this system since (i) the orbit has a significant eccentricity despite its short period and (ii) the systemic velocity V0 shows a possible drift. For the second system, HD 98880, we give Delta mB 1.25 and we propose a simple model based upon Strömgren photometric indices and the HR theoretical diagram of Schaller et al (1992) in addition to orbital parameters and Hipparcos data: Teff = 7000 K, log 10 g = 4.0, M1 = 1.9 Msun, M2 = 1.6 Msun, log 10(age) = 9.12. The components do not rotate synchronously contrary to HD 81976. Both binaries appear to be detached systems without possibility of eclipses. Based on observations made at the Haute-Provence Observatory, France.

The receptor tyrosine kinase Pvr promotes tissue closure by coordinating corpse removal and epidermal zippering

PubMed Central

Garlena, Rebecca A.; Lennox, Ashley L.; Baker, Lewis R.; Parsons, Trish E.; Weinberg, Seth M.; Stronach, Beth E.

2015-01-01

A leading cause of human birth defects is the incomplete fusion of tissues, often manifested in the palate, heart or neural tube. To investigate the molecular control of tissue fusion, embryonic dorsal closure and pupal thorax closure in Drosophila are useful experimental models. We find that Pvr mutants have defects in dorsal midline closure with incomplete amnioserosa internalization and epidermal zippering, as well as cardia bifida. These defects are relatively mild in comparison to those seen with other signaling mutants, such as in the JNK pathway, and we demonstrate that JNK signaling is not perturbed by altering Pvr receptor tyrosine kinase activity. Rather, modulation of Pvr levels in the ectoderm has an impact on PIP3 membrane accumulation, consistent with a link to PI3K signal transduction. Polarized PI3K activity influences protrusive activity from the epidermal leading edge and the protrusion area changes in accord with Pvr signaling intensity, providing a possible mechanism to explain Pvr mutant phenotypes. Tissue-specific rescue experiments indicate a partial requirement in epithelial tissue, but confirm the essential role of Pvr in hemocytes for embryonic survival. Taken together, we argue that inefficient removal of the internalizing amnioserosa tissue by mutant hemocytes coupled with impaired midline zippering of mutant epithelium creates a situation in some embryos whereby dorsal midline closure is incomplete. Based on these observations, we suggest that efferocytosis (corpse clearance) could contribute to proper tissue closure and thus might underlie some congenital birth defects. PMID:26293306

Elementary School Students with AD/HD: Predictors of Academic Achievement

ERIC Educational Resources Information Center

DuPaul, G.J.; Volpe, R. J.; Jitendra, A. K.; Lutz, J. G.; Lorah, K. S.; Gruber, R.

2004-01-01

Academic underachievement frequently is associated with attention-deficit/hyperactivity disorder (AD/HD); however, the role of variables beyond AD/HD symptoms and cognitive mediators is unknown. Further, whether prediction models vary (a) relative to non-AD/HD students, (b) between math and reading, and (c) based on how achievement is defined has…

Transcription Factors Responding to Pb Stress in Maize

PubMed Central

Zhang, Yanling; Ge, Fei; Hou, Fengxia; Sun, Wenting; Zheng, Qi; Zhang, Xiaoxiang; Ma, Langlang; Fu, Jun; He, Xiujing; Peng, Huanwei; Pan, Guangtang; Shen, Yaou

2017-01-01

Pb can damage the physiological function of human organs by entering the human body via food-chain enrichment. Revealing the mechanisms of maize tolerance to Pb is critical for preventing this. In this study, a Pb-tolerant maize inbred line, 178, was used to analyse transcription factors (TFs) expressed under Pb stress based on RNA sequencing data. A total of 464 genes expressed in control check (CK) or Pb treatment samples were annotated as TFs. Among them, 262 differentially expressed transcription factors (DETs) were identified that responded to Pb treatment. Furthermore, the DETs were classified into 4 classes according to their expression patterns, and 17, 12 and 2 DETs were significantly annotated to plant hormone signal transduction, basal transcription factors and base excision repair, respectively. Seventeen DETs were found to participate in the plant hormone signal transduction pathway, where basic leucine zippers (bZIPs) were the most significantly enriched TFs, with 12 members involved. We further obtained 5 Arabidopsis transfer DNA (T-DNA) mutants for 6 of the maize bZIPs, among which the mutants atbzip20 and atbzip47, representing ZmbZIP54 and ZmbZIP107, showed obviously inhibited growth of roots and above-ground parts, compared with wild type. Five highly Pb-tolerant and 5 highly Pb-sensitive in maize lines were subjected to DNA polymorphism and expression level analysis of ZmbZIP54 and ZmbZIP107. The results suggested that differences in bZIPs expression partially accounted for the differences in Pb-tolerance among the maize lines. Our results contribute to the understanding of the molecular regulation mechanisms of TFs in maize under Pb stress. PMID:28927013

Enhanced Gene Expression Rather than Natural Polymorphism in Coding Sequence of the OsbZIP23 Determines Drought Tolerance and Yield Improvement in Rice Genotypes

PubMed Central

Dey, Avishek; Samanta, Milan Kumar; Gayen, Srimonta; Sen, Soumitra K.; Maiti, Mrinal K.

2016-01-01

Drought is one of the major limiting factors for productivity of crops including rice (Oryza sativa L.). Understanding the role of allelic variations of key regulatory genes involved in stress-tolerance is essential for developing an effective strategy to combat drought. The bZIP transcription factors play a crucial role in abiotic-stress adaptation in plants via abscisic acid (ABA) signaling pathway. The present study aimed to search for allelic polymorphism in the OsbZIP23 gene across selected drought-tolerant and drought-sensitive rice genotypes, and to characterize the new allele through overexpression (OE) and gene-silencing (RNAi). Analyses of the coding DNA sequence (CDS) of the cloned OsbZIP23 gene revealed single nucleotide polymorphism at four places and a 15-nucleotide deletion at one place. The single-copy OsbZIP23 gene is expressed at relatively higher level in leaf tissues of drought-tolerant genotypes, and its abundance is more in reproductive stage. Cloning and sequence analyses of the OsbZIP23-promoter from drought-tolerant O. rufipogon and drought-sensitive IR20 cultivar showed variation in the number of stress-responsive cis-elements and a 35-nucleotide deletion at 5’-UTR in IR20. Analysis of the GFP reporter gene function revealed that the promoter activity of O. rufipogon is comparatively higher than that of IR20. The overexpression of any of the two polymorphic forms (1083 bp and 1068 bp CDS) of OsbZIP23 improved drought tolerance and yield-related traits significantly by retaining higher content of cellular water, soluble sugar and proline; and exhibited decrease in membrane lipid peroxidation in comparison to RNAi lines and non-transgenic plants. The OE lines showed higher expression of target genes-OsRab16B, OsRab21 and OsLEA3-1 and increased ABA sensitivity; indicating that OsbZIP23 is a positive transcriptional-regulator of the ABA-signaling pathway. Taken together, the present study concludes that the enhanced gene expression rather

NV-CMOS HD camera for day/night imaging

NASA Astrophysics Data System (ADS)

Vogelsong, T.; Tower, J.; Sudol, Thomas; Senko, T.; Chodelka, D.

2014-06-01

SRI International (SRI) has developed a new multi-purpose day/night video camera with low-light imaging performance comparable to an image intensifier, while offering the size, weight, ruggedness, and cost advantages enabled by the use of SRI's NV-CMOS HD digital image sensor chip. The digital video output is ideal for image enhancement, sharing with others through networking, video capture for data analysis, or fusion with thermal cameras. The camera provides Camera Link output with HD/WUXGA resolution of 1920 x 1200 pixels operating at 60 Hz. Windowing to smaller sizes enables operation at higher frame rates. High sensitivity is achieved through use of backside illumination, providing high Quantum Efficiency (QE) across the visible and near infrared (NIR) bands (peak QE <90%), as well as projected low noise (<2h+) readout. Power consumption is minimized in the camera, which operates from a single 5V supply. The NVCMOS HD camera provides a substantial reduction in size, weight, and power (SWaP) , ideal for SWaP-constrained day/night imaging platforms such as UAVs, ground vehicles, fixed mount surveillance, and may be reconfigured for mobile soldier operations such as night vision goggles and weapon sights. In addition the camera with the NV-CMOS HD imager is suitable for high performance digital cinematography/broadcast systems, biofluorescence/microscopy imaging, day/night security and surveillance, and other high-end applications which require HD video imaging with high sensitivity and wide dynamic range. The camera comes with an array of lens mounts including C-mount and F-mount. The latest test data from the NV-CMOS HD camera will be presented.

The homeodomain transcription factor TaHDZipI-2 from wheat regulates frost tolerance, flowering time and spike development in transgenic barley.

PubMed

Kovalchuk, Nataliya; Chew, William; Sornaraj, Pradeep; Borisjuk, Nikolai; Yang, Nannan; Singh, Rohan; Bazanova, Natalia; Shavrukov, Yuri; Guendel, Andre; Munz, Eberhard; Borisjuk, Ljudmilla; Langridge, Peter; Hrmova, Maria; Lopato, Sergiy

2016-07-01

Homeodomain leucine zipper class I (HD-Zip I) transcription factors (TFs) play key roles in the regulation of plant growth and development under stresses. Functions of the TaHDZipI-2 gene isolated from the endosperm of developing wheat grain were revealed. Molecular characterization of TaHDZipI-2 protein included studies of its dimerisation, protein-DNA interactions and gene activation properties using pull-down assays, in-yeast methods and transient expression assays in wheat cells. The analysis of TaHDZipI-2 gene functions was performed using transgenic barley plants. It included comparison of developmental phenotypes, yield components, grain quality, frost tolerance and the levels of expression of potential target genes in transgenic and control plants. Transgenic TaHDZipI-2 lines showed characteristic phenotypic features that included reduced growth rates, reduced biomass, early flowering, light-coloured leaves and narrowly elongated spikes. Transgenic lines produced 25-40% more seeds per spike than control plants, but with 50-60% smaller grain size. In vivo lipid imaging exposed changes in the distribution of lipids between the embryo and endosperm in transgenic seeds. Transgenic lines were significantly more tolerant to frost than control plants. Our data suggest the role of TaHDZipI-2 in controlling several key processes underlying frost tolerance, transition to flowering and spike development. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

Spectral images of HD 199178

NASA Technical Reports Server (NTRS)

Neff, J. E.; Vilhu, O.; Walter, F. M.

1988-01-01

High-resolution IUE spectra of the Mg II k line of HD 199178 were analyzed, applying spectral imaging techniques to derive an image of the chromospheric structure and to study the transient behavior of the chromosphere. All spectra in the IUE archives were uniformly reduced and analyzed. Results are compared with ground-based observations of the photosphere. Four ultraviolet flares on HD 199178 are observed; 3 of these occurred at roughly the same rotational phase. There is no clear phase-dependence of the SWP line fluxes, but there is for the Mg II k flux. The emission centroid of the Mg II k line varies in a quasi-sinusoidal fashion, presumably due to the rotation of a nonuniform chromosphere.

SnRK1-triggered switch of bZIP63 dimerization mediates the low-energy response in plants

PubMed Central

Mair, Andrea; Pedrotti, Lorenzo; Wurzinger, Bernhard; Anrather, Dorothea; Simeunovic, Andrea; Weiste, Christoph; Valerio, Concetta; Dietrich, Katrin; Kirchler, Tobias; Nägele, Thomas; Vicente Carbajosa, Jesús; Hanson, Johannes; Baena-González, Elena; Chaban, Christina; Weckwerth, Wolfram; Dröge-Laser, Wolfgang; Teige, Markus

2015-01-01

Metabolic adjustment to changing environmental conditions, particularly balancing of growth and defense responses, is crucial for all organisms to survive. The evolutionary conserved AMPK/Snf1/SnRK1 kinases are well-known metabolic master regulators in the low-energy response in animals, yeast and plants. They act at two different levels: by modulating the activity of key metabolic enzymes, and by massive transcriptional reprogramming. While the first part is well established, the latter function is only partially understood in animals and not at all in plants. Here we identified the Arabidopsis transcription factor bZIP63 as key regulator of the starvation response and direct target of the SnRK1 kinase. Phosphorylation of bZIP63 by SnRK1 changed its dimerization preference, thereby affecting target gene expression and ultimately primary metabolism. A bzip63 knock-out mutant exhibited starvation-related phenotypes, which could be functionally complemented by wild type bZIP63, but not by a version harboring point mutations in the identified SnRK1 target sites. DOI: http://dx.doi.org/10.7554/eLife.05828.001 PMID:26263501

A HIGH-ECCENTRICITY COMPONENT IN THE DOUBLE-PLANET SYSTEM AROUND HD 163607 AND A PLANET AROUND HD 164509

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

Giguere, Matthew J.; Fischer, Debra A.; Spronck, Julien

2012-01-01

We report the detection of three new exoplanets from Keck Observatory. HD 163607 is a metal-rich G5IV star with two planets. The inner planet has an observed orbital period of 75.29 {+-} 0.02 days, a semi-amplitude of 51.1 {+-} 1.4 m s{sup -1}, an eccentricity of 0.73 {+-} 0.02, and a derived minimum mass of M{sub P} sin i = 0.77 {+-} 0.02 M{sub Jup}. This is the largest eccentricity of any known planet in a multi-planet system. The argument of periastron passage is 78.7 {+-} 2.{sup 0}0; consequently, the planet's closest approach to its parent star is very nearmore » the line of sight, leading to a relatively high transit probability of 8%. The outer planet has an orbital period of 3.60 {+-} 0.02 years, an orbital eccentricity of 0.12 {+-} 0.06, and a semi-amplitude of 40.4 {+-} 1.3 m s{sup -1}. The minimum mass is M{sub P} sin i = 2.29 {+-} 0.16 M{sub Jup}. HD 164509 is a metal-rich G5V star with a planet in an orbital period of 282.4 {+-} 3.8 days and an eccentricity of 0.26 {+-} 0.14. The semi-amplitude of 14.2 {+-} 2.7 m s{sup -1} implies a minimum mass of 0.48 {+-} 0.09 M{sub Jup}. The radial velocities (RVs) of HD 164509 also exhibit a residual linear trend of -5.1 {+-} 0.7 m s{sup -1} year{sup -1}, indicating the presence of an additional longer period companion in the system. Photometric observations demonstrate that HD 163607 and HD 164509 are constant in brightness to submillimagnitude levels on their RV periods. This provides strong support for planetary reflex motion as the cause of the RV variations.« less

Monitoring Cole-Cole parameters during haemodialysis (HD).

PubMed

Al-Surkhi, Omar I; Riu, P J; Vazquez, F F; Ibeas, J

2007-01-01

The investigation of the hydration process during the haemodialysis treatment sessions is very important for the development of methods for predicting the unbalanced fluid shifts and hypotension crisis hence improving the quality of the haemodialysis procedure. Bioimpedance measurements can give valuable information about the tissue under measurement, therefore characterizing the tissue. In this work we propose a non-invasive method based on local multifrequency bioimpedance measurements that allow us to determine the fluid distribution and variations during haemodialysis. Clinical measurements were done using 10 HD patients during 60 HD sessions. Bioimpedance data, ultrafiltration volume, blood volume and blood heamatocrit variations were recorded continuously during the HD sessions. Bioimpedance of the local tissue was measured with a 4-elctrode impedance system using surface electrodes with sampling rate of 1meas./4min. at 6 different frequencies. The measured impedances were fitted into Cole-Cole model and the Cole-Cole parameters were continuously determined for each measurement point during the HD session. The 4 Cole-Cole parameters (R 00, R 0, Fc,alpha) and their variations were evaluated. Impedance values at infinite and zero (R 00, R 0) frequencies were extrapolated from Cole-Cole mathematical model. These values are assumed to represent the impedance of total tissue fluid and the impedance of the extracellular space respectively.

A study of the spectrum of HD 108, an unusual Of star

NASA Astrophysics Data System (ADS)

Underhill, Anne B.

1994-01-01

Spectra of the peculiar O star HD 108 obtained at a scale of 30 A/mm in the years 1986-1991 have been studied for line displacements and line profiles. The wavelength regions covered are 4180-5050 A, 5100-5980 A, and 6180-7070 A. The spectra were recorded with a Reticon, and most have a signal-to-noise ratio per pixel in the continuum greater than 200. It is argued that the spectral type is best described as O7fpe III. The spectrum at the time of observation was similar to te description given by Plaskett (1924), but the radial velocity has changed. In 1922 and 1923 the absorption lines and the emission lines showed a displacement of -62 km/s. In the ensuing years the radial velocity shown by the absorption lines, mostly He II, N III, and O III, has changed to about -84 km/s in 1991. The emission-line velocity remained near -62 km/s until about 1991, when this radial velocity became (apparently) about -66 km/s. There is some reason to suspect that the last few spectra obtained in 1991 suffer from a small random negative shift. The meaning of the radial velocity results is discussed, and it is argued that by 1973 the photosphere may have begun to undergo an outward surge. The change of motion shown by the emission lines is less than that shown by the photospheric absorption lines. It is argued that the emission lines, both the strong sharp emission lines due to H and He I and the weaker lines due to C II, C III, N II, O II, and Si III, are formed in a polar jet which is moving almost perpendicular to the line of sight. The star HD 108 appears to be related to the luminous blues variables (LBVs) and to the B(e) stars. No forbidden emission lines, as from a nebula, were detected in the visible spectral range. Strong distinctive P Cygni type displaced absorption components for the H and He I lines are not seen. Rather, one sees a sharp emission line superposed on a photospehric absorption line. The absence of a strong P Cygni type absorption component indicates that

The HD 163296 Circumstellar Disk in Scattered Light: Evidence of Time-Variable Self-Shadowing

NASA Technical Reports Server (NTRS)

Wisniewski, John P.; Clampin, Mark; Grady, Carol A.; Ardila, David R.; Ford, Holland C.; Golimowski, David A.; Illingworth, Garth D.; Krist, John E.

2008-01-01

We present the first multi-color view of the scattered light disk of the Herbig Ae star HD 163296, based on coronagraphic observations from the Hubble Space Telescope Advanced Camera for Surveys (ACS). Radial profile fits of the surface brightness along the disk's semi-major axis indicates that the disk is not continuously flared, and extends to approx.540 AU. The disk's color (V-I)=1.1 at a radial distance of 3.5" is redder than the observed stellar color (V-I)=0.15. This red disk color might be indicative of either an evolution in the grain size distribution (i.e. grain growth) and/or composition, both of which would be consistent with the observed non-flared geometry of the outer disk. We also identify a single ansa morphological structure in our F435W ACS data, which is absent from earlier epoch F606W and F814W ACS data, but corresponds to one of the two ansa observed in archival HST STIS coronagraphic data. Following transformation to similar band-passes, we find that the scattered light disk of HD 163296 is 1 mag arcsec(sup -2) fainter at 3.5" in the STIS data than in the ACS data. Moreover, variations are seen in (i) the visibility of the ansa(e) structures, in (ii) the relative surface brightness of the ansa(e) structures, and in (iii) the (known) intrinsic polarization of the system. These results indicate that the scattered light from the HD 163296 disk is variable. We speculate that the inner disk wall, which Sitko et al. suggests has a variable scale height as diagnosed by near-IR SED variability, induces variable self-shadowing of the outer disk. We further speculate that the observed surface brightness variability of the ansa(e) structures may indicate that the inner disk wall is azimuthally asymmetric. Subject headings: circumstellar matter - stars: individual (HD 163296) - planetary systems: formation - planetary systems: protoplanetary disks

Rotationally excited HD toward Zeta Ophiuchi

NASA Technical Reports Server (NTRS)

Wright, E. L.; Morton, D. C.

1979-01-01

Copernicus satellite measurements of HD in J-double prime = 1 and J-double prime = 0 toward Zeta Oph are reported. The ratio of the number densities of HD in the J = 0 and J = 1 states is determined to be 0.15 + or - 0.02 at the 1-sigma level. A value of approximately 24 x 10 to the -17th erg/cu cm per A at 1000 A is obtained for the UV energy density at the Zeta Oph cloud, and the mechanisms for excitation of HD are examined. A tight upper limit is derived for the abundance of HCl, which has been predicted to be present due to the interaction of ionized chlorine with neutral hydrogen. A calculation is performed which indicates that the cloud is 28 pc from the star. It is shown that the two-component cloud model of Black and Dalgarno (1977) with densities of 500 and 2500 H nuclei per cu cm for the outer regions and core, respectively, is in excellent agreement with the observations.

Far-infrared HD emission as a measure of protoplanetary disk mass

NASA Astrophysics Data System (ADS)

Trapman, L.; Miotello, A.; Kama, M.; van Dishoeck, E. F.; Bruderer, S.

2017-09-01

Context. Protoplanetary disks around young stars are the sites of planet formation. While the dust mass can be estimated using standard methods, determining the gas mass - and thus the amount of material available to form giant planets - has proven to be very difficult. Hydrogen deuteride (HD) is a promising alternative to the commonly used gas mass tracer, carbon monoxide. However, the potential of HD has not yet been investigated with models incorporating both HD and CO isotopologue-specific chemistry, and its sensitivity to uncertainties in disk parameters has not yet been quantified. Aims: We examine the robustness of HD as tracer of the disk gas mass, specifically the effect of gas mass on HD far-infrared emission and its sensitivity to the vertical structure. Also, we seek to provide requirements for future far-infrared missions such as SPICA. Methods: Deuterium chemistry reactions relevant for HD were implemented in the thermochemical code DALI and more than 160 disk models were run for a range of disk masses and vertical structures. Results: The HD J = 1-0 line intensity depends directly on the gas mass through a sublinear power law relation with a slope of 0.8. Assuming no prior knowledge about the vertical structure of a disk and using only the HD 1-0 flux, gas masses can be estimated to within a factor of two for low mass disks (Mdisk ≤ 10-3M⊙). For more massive disks, this uncertainty increases to more than an order of magnitude. Adding the HD 2-1 line or independent information about the vertical structure can reduce this uncertainty to a factor of 3 for all disk masses. For TW Hya, using the radial and vertical structure from the literature, the observations constrain the gas mass to 6 × 10-3M⊙ ≤ Mdisk ≤ 9 × 10-3M⊙. Future observations require a 5σ sensitivity of 1.8 × 10-20 W m-2 (2.5 × 10-20 W m-2) and a spectral resolving power R ≥ 300 (1000) to detect HD 1-0 (HD 2-1) for all disk masses above 10-5M⊙ with a line

Chromatin Immunoprecipitation and Microarray Analysis Suggest Functional Cooperation between Kaposi's Sarcoma-Associated Herpesvirus ORF57 and K-bZIP

PubMed Central

Hunter, Olga V.; Sei, Emi; Richardson, R. Blake

2013-01-01

The Kaposi's sarcoma-associated herpesvirus (KSHV) open reading frame 57 (ORF57)-encoded protein (Mta) is a multifunctional regulator of viral gene expression. ORF57 is essential for viral replication, so elucidation of its molecular mechanisms is important for understanding KSHV infection. ORF57 has been implicated in nearly every aspect of viral gene expression, including transcription, RNA stability, splicing, export, and translation. Here we demonstrate that ORF57 interacts with the KSHV K-bZIP protein in vitro and in cell extracts from lytically reactivated infected cells. To further test the biological relevance of the interaction, we performed a chromatin immunoprecipitation and microarray (ChIP-chip) analysis using anti-ORF57 antibodies and a KSHV tiling array. The results revealed four specific areas of enrichment, including the ORF4 and K8 (K-bZIP) promoters, as well as oriLyt, all of which interact with K-bZIP. In addition, ORF57 associated with DNA corresponding to the PAN RNA transcribed region, a known posttranscriptional target of ORF57. All of the peaks were RNase insensitive, demonstrating that ORF57 association with the viral genome is unlikely to be mediated exclusively by an RNA tether. Our data demonstrate that ORF57 associates with the viral genome by using at least two modes of recruitment, and they suggest that ORF57 and K-bZIP coregulate viral gene expression during lytic infection. PMID:23365430

FATE-HD: A spatially and temporally explicit integrated model for predicting vegetation structure and diversity at regional scale

PubMed Central

Isabelle, Boulangeat; Damien, Georges; Wilfried, Thuiller

2014-01-01

During the last decade, despite strenuous efforts to develop new models and compare different approaches, few conclusions have been drawn on their ability to provide robust biodiversity projections in an environmental change context. The recurring suggestions are that models should explicitly (i) include spatiotemporal dynamics; (ii) consider multiple species in interactions; and (iii) account for the processes shaping biodiversity distribution. This paper presents a biodiversity model (FATE-HD) that meets this challenge at regional scale by combining phenomenological and process-based approaches and using well-defined plant functional groups. FATE-HD has been tested and validated in a French National Park, demonstrating its ability to simulate vegetation dynamics, structure and diversity in response to disturbances and climate change. The analysis demonstrated the importance of considering biotic interactions, spatio-temporal dynamics, and disturbances in addition to abiotic drivers to simulate vegetation dynamics. The distribution of pioneer trees was particularly improved, as were all undergrowth functional groups. PMID:24214499

Cometary Dust in the Debris of HD 31648 and HD163296: Two "Baby" Beta pictoris Stars

NASA Technical Reports Server (NTRS)

Sitko, Michael L.; Grady, Carol A.; Lynch, David K.; Russell, Ray W.; Hanner, Martha S.

1999-01-01

The debris disks surrounding the pre-main-sequence stars HD 31648 and HD 163296 were observed spectroscopically between 3 and 14 microns. Both stars possess a silicate emission feature at 10 Am that resembles that of the star P Pictoris and those observed in solar system comets. The structure of the band is consistent with a mixture of olivine and pyroxene material, plus an underlying continuum of unspecified origin. The similarity in both size and structure of the silicate band suggests that the material in these systems had a processing history similar to that in our own solar system prior to the time that the grains were incorporated into comets.

Non-local Thermodynamic Equilibrium Abundance Analyses of the Extreme Helium Stars V652 Her and HD 144941

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

Pandey, Gajendra; Lambert, David L., E-mail: pandey@iiap.res.in, E-mail: dll@astro.as.utexas.edu

Optical high-resolution spectra of V652 Her and HD 144941, the two extreme helium stars with exceptionally low C/He ratios, have been subjected to a non-LTE abundance analysis using the tools TLUSTY and SYNSPEC. Defining atmospheric parameters were obtained from a grid of non-LTE atmospheres and a variety of spectroscopic indicators including He i and He ii line profiles, and the ionization equilibrium of ion pairs such as C ii/C iii and N ii/N iii. The various indicators provide a consistent set of atmospheric parameters: T {sub eff} = 25,000 ± 300 K, log g = 3.10 ± 0.12(cgs), and ξmore » = 13 ± 2 km s{sup −1} are provided for V652 Her, and T {sub eff} = 22,000 ± 600 K, log g = 3.45 ± 0.15 (cgs), and ξ = 10 km s{sup −1} are provided for HD 144941. In contrast to the non-LTE analyses, the LTE analyses—LTE atmospheres and an LTE line analysis—with the available indicators do not provide a consistent set of atmospheric parameters. The principal non-LTE effect on the elemental abundances is on the neon abundance. It is generally considered that these extreme helium stars with their very low C/He ratio result from the merger of two helium white dwarfs. Indeed, the derived composition of V652 Her is in excellent agreement with predictions by Zhang and Jeffery, who model the slow merger of helium white dwarfs; a slow merger results in the merged star having the composition of the accreted white dwarf. In the case of HD 144941, which appears to have evolved from metal-poor stars, a slow merger is incompatible with the observed composition but variations of the merger rate may account for the observed composition. More detailed theoretical studies of the merger of a pair of helium white dwarfs are to be encouraged.« less

Myopic (HD-PTP, PTPN23) selectively regulates synaptic neuropeptide release.

PubMed

Bulgari, Dinara; Jha, Anupma; Deitcher, David L; Levitan, Edwin S

2018-02-13

Neurotransmission is mediated by synaptic exocytosis of neuropeptide-containing dense-core vesicles (DCVs) and small-molecule transmitter-containing small synaptic vesicles (SSVs). Exocytosis of both vesicle types depends on Ca 2+ and shared secretory proteins. Here, we show that increasing or decreasing expression of Myopic (mop, HD-PTP, PTPN23), a Bro1 domain-containing pseudophosphatase implicated in neuronal development and neuropeptide gene expression, increases synaptic neuropeptide stores at the Drosophila neuromuscular junction (NMJ). This occurs without altering DCV content or transport, but synaptic DCV number and age are increased. The effect on synaptic neuropeptide stores is accounted for by inhibition of activity-induced Ca 2+ -dependent neuropeptide release. cAMP-evoked Ca 2+ -independent synaptic neuropeptide release also requires optimal Myopic expression, showing that Myopic affects the DCV secretory machinery shared by cAMP and Ca 2+ pathways. Presynaptic Myopic is abundant at early endosomes, but interaction with the endosomal sorting complex required for transport III (ESCRT III) protein (CHMP4/Shrub) that mediates Myopic's effect on neuron pruning is not required for control of neuropeptide release. Remarkably, in contrast to the effect on DCVs, Myopic does not affect release from SSVs. Therefore, Myopic selectively regulates synaptic DCV exocytosis that mediates peptidergic transmission at the NMJ.

Prion protein functions as a ferrireductase partner for ZIP14 and DMT1

PubMed Central

Qian, Juan; Beserra, Amber; Suda, Srinivas; Singh, Ajay; Hopfer, Ulrich; Chen, Shu G.; Garrick, Michael D.; Turner, Jerrold R.; Knutson, Mitchell D.; Singh, Neena

2015-01-01

Excess circulating iron is stored in the liver, and requires reduction of non-Tf-bound-iron (NTBI) and transferrin (Tf)-iron at the plasma membrane and endosomes respectively by ferrireductase (FR) proteins for transport across biological membranes through divalent metal transporters. Here, we report that prion-protein (PrPC), a ubiquitously expressed glycoprotein most abundant on neuronal cells, functions as a FR partner for divalent-metal transporter-1 (DMT1) and ZIP14. Thus, absence of PrPC in PrP-knock-out (PrP−/−) mice resulted in markedly reduced liver iron stores, a deficiency that was not corrected by chronic or acute administration of iron by the oral or intra-peritoneal routes. Likewise, preferential radiolabeling of circulating NTBI with 59Fe revealed significantly reduced uptake and storage of NTBI by the liver of PrP−/− mice relative to matched PrP+/+ controls. However, uptake, storage, and utilization of ferritin-bound iron that does not require reduction for uptake was increased in PrP−/− mice, indicating a compensatory response to the iron-deficiency. Expression of exogenous PrPC in HepG2-cells increased uptake and storage of ferric-iron (Fe3+), not ferrous-iron (Fe2+) from the medium, supporting the function of PrPC as a plasma membrane FR. Co-expression of PrPC with ZIP14 and DMT1 in HepG2 cells increased uptake of Fe3+ significantly, and surprisingly, increased the ratio of N-terminally truncated PrPC forms lacking the FR domain relative to full-length PrPC. Together, these observations indicate that PrPC promotes, and possibly regulates the uptake of NTBI through DMT1 and Zip14 via its FR activity. Implications of these observations for neuronal iron homeostasis under physiological and pathological conditions are discussed. PMID:25862412

Cryogenic Characterization of FBK RGB-HD SiPMs

NASA Astrophysics Data System (ADS)

Aalseth, C. E.; Acerbi, F.; Agnes, P.; Albuquerque, I. F. M.; Alexander, T.; Alici, A.; Alton, A. K.; Ampudia, P.; Antonioli, P.; Arcelli, S.; Ardito, R.; Arnquist, I. J.; Asner, D. M.; Back, H. O.; Batignani, G.; Bertoldo, E.; Bettarini, S.; Bisogni, M. G.; Bocci, V.; Bondar, A.; Bonfini, G.; Bonivento, W.; Bossa, M.; Bottino, B.; Bunker, R.; Bussino, S.; Buzulutskov, A.; Cadeddu, M.; Cadoni, M.; Caminata, A.; Canci, N.; Candela, A.; Cantini, C.; Caravati, M.; Cariello, M.; Carlini, M.; Carpinelli, M.; Castellani, A.; Catalanotti, S.; Cataudella, V.; Cavalcante, P.; Cereseto, R.; Chen, Y.; Chepurnov, A.; Chiavassa, A.; Cicalò, C.; Cifarelli, L.; Citterio, M.; Cocco, A. G.; Colocci, M.; Corgiolu, S.; Covone, G.; Crivelli, P.; D'Antone, I.; D'Incecco, M.; Da Rocha Rolo, M. D.; Daniel, M.; Davini, S.; De Candia, A.; De Cecco, S.; De Deo, M.; De Filippis, G.; De Guido, G.; De Rosa, G.; Dellacasa, G.; Demontis, P.; Derbin, A. V.; Devoto, A.; Di Eusanio, F.; Di Pietro, G.; Dionisi, C.; Dolgov, A.; Dormia, I.; Dussoni, S.; Empl, A.; Ferri, A.; Filip, C.; Fiorillo, G.; Fomenko, K.; Franco, D.; Froudakis, G. E.; Gabriele, F.; Gabrieli, A.; Galbiati, C.; Garcia Abia, P.; Gendotti, A.; Ghisi, A.; Giagu, S.; Gibertoni, G.; Giganti, C.; Giorgi, M.; Giovanetti, G. K.; Gligan, M. L.; Gola, A.; Gorchakov, O.; Goretti, A. M.; Granato, F.; Grassi, M.; Grate, J. W.; Grigoriev, G. Y.; Gromov, M.; Guan, M.; Guerra, M. B. B.; Guerzoni, M.; Gulino, M.; Haaland, R. K.; Harrop, B.; Hoppe, E. W.; Horikawa, S.; Hosseini, B.; Hughes, D.; Humble, P.; Hungerford, E. V.; Ianni, An.; Jimenez Cabre, S.; Johnson, T. N.; Keeter, K.; Kendziora, C. L.; Kim, S.; Koh, G.; Korablev, D.; Korga, G.; Kubankin, A.; Kugathasan, R.; Kuss, M.; Li, X.; Lissia, M.; Lodi, G. U.; Loer, B.; Longo, G.; Lussana, R.; Luzzi, L.; Ma, Y.; Machado, A. A.; Machulin, I. N.; Mais, L.; Mandarano, A.; Mapelli, L.; Marcante, M.; Margotti, A.; Mari, S. M.; Mariani, M.; Maricic, J.; Marinelli, M.; Marras, D.; Martoff, C. J.; Mascia, M.; Messina, A.; Meyers, P. D.; Milincic, R.; Moggi, A.; Moioli, S.; Monasterio, S.; Monroe, J.; Monte, A.; Morrocchi, M.; Mu, W.; Muratova, V. N.; Murphy, S.; Musico, P.; Nania, R.; Napolitano, J.; Navrer Agasson, A.; Nikulin, I.; Nosov, V.; Nozdrina, A. O.; Nurakhov, N. N.; Oleinik, A.; Oleynikov, V.; Orsini, M.; Ortica, F.; Pagani, L.; Pallavicini, M.; Palmas, S.; Pandola, L.; Pantic, E.; Paoloni, E.; Paternoster, G.; Pavletcov, V.; Pazzona, F.; Pelczar, K.; Pellegrini, L. A.; Pelliccia, N.; Perotti, F.; Perruzza, R.; Piemonte, C.; Pilo, F.; Pocar, A.; Portaluppi, D.; Poudel, S. S.; Pugachev, D. A.; Qian, H.; Radics, B.; Raffaelli, F.; Ragusa, F.; Randle, K.; Razeti, M.; Razeto, A.; Regazzoni, V.; Regenfus, C.; Reinhold, B.; Renshaw, A. L.; Rescigno, M.; Riffard, Q.; Rivetti, A.; Romani, A.; Romero, L.; Rossi, B.; Rossi, N.; Rubbia, A.; Sablone, D.; Salatino, P.; Samoylov, O.; Sands, W.; Sant, M.; Santorelli, R.; Savarese, C.; Scapparone, E.; Schlitzer, B.; Scioli, G.; Sechi, E.; Segreto, E.; Seifert, A.; Semenov, D. A.; Serci, S.; Shchagin, A.; Shekhtman, L.; Shemyakina, E.; Sheshukov, A.; Simeone, M.; Singh, P. N.; Skorokhvatov, M. D.; Smirnov, O.; Sobrero, G.; Sokolov, A.; Sotnikov, A.; Stanford, C.; Suffritti, G. B.; Suvorov, Y.; Tartaglia, R.; Testera, G.; Tonazzo, A.; Tosi, A.; Trinchese, P.; Unzhakov, E. V.; Vacca, A.; Verducci, M.; Viant, T.; Villa, F.; Vishneva, A.; Vogelaar, B.; Wada, M.; Wahl, J.; Walker, S.; Wang, H.; Wang, Y.; Watson, A. W.; Westerdale, S.; Wilhelmi, J.; Williams, R.; Wojcik, M. M.; Wu, S.; Xiang, X.; Xiao, X.; Yang, C.; Ye, Z.; Zappa, F.; Zappalà, G.; Zhu, C.; Zichichi, A.; Zuzel, G.

2017-09-01

We report on the cryogenic characterization of Red Green Blue - High Density (RGB-HD) SiPMs developed at Fondazione Bruno Kessler (FBK) as part of the DarkSide program of dark matter searches with liquid argon time projection chambers. A cryogenic setup was used to operate the SiPMs at varying temperatures and a custom data acquisition system and analysis software were used to precisely characterize the primary dark noise, the correlated noise, and the gain of the devices. We demonstrate that FBK RGB-HD SiPMs with low quenching resistance (RGB-HD-LRq) can be operated from 40 K to 300 K with gains in the range 105 to 106 and noise rates at a level of around 1 Hz/mm2.

The ArcB Leucine Zipper Domain Is Required for Proper ArcB Signaling

PubMed Central

Nuñez Oreza, Luis Alberto; Alvarez, Adrián F.; Arias-Olguín, Imilla I.; Torres Larios, Alfredo; Georgellis, Dimitris

2012-01-01

The Arc two-component system modulates the expression of numerous genes in response to respiratory growth conditions. This system comprises ArcA as the response regulator and ArcB as the sensor kinase. ArcB is a tripartite histidine kinase whose activity is regulated by the oxidation of two cytosol-located redox-active cysteine residues that participate in intermolecular disulfide bond formation. Here, we report that the ArcB protein segment covering residues 70–121, fulfills the molecular characteristics of a leucine zipper containing coiled coil structure. Also, mutational analyses of this segment reveal three different phenotypical effects to be distributed along the coiled coil structure of ArcB, demonstrating that this motif is essential for proper ArcB signaling. PMID:22666479

HD-tDCS in refractory lateral frontal lobe epilepsy patients.

PubMed

Karvigh, Sanaz Ahmadi; Motamedi, Mahmoud; Arzani, Mahsa; Roshan, Javad Hasan Nia

2017-04-01

To evaluate the anticonvulsant effect of the novel high definition transcranial direct current stimulation (HD-tDCS) method on patients with refractory lateral frontal lobe epilepsy. The effects of HD-tDCS on working memory were also examined. 10 adult patients with intractable lateral frontal lobe epilepsy were studied. A central cathode electrode was placed on the epileptogenic zone according to LTM, and 20-min sessions of 2mA HD-tDCS were applied for 10 consecutive days. The primary endpoint was to make changes in the epileptiform discharges (EDs) during a 1-h EEG. Moreover, the seizure frequency based on seizure diary and neuropsychiatric parameters was evaluated. All patients tolerated HD-tDCS stimulation course without any adverse reaction. The frequency of EDs increased immediately and one month after the stimulation course by an average of 6.4% and 1.2%, respectively. However, these changes in the EDs frequency were not statistically significant (p-value >0.05). The mean seizure frequency changes showed decrement by an average of 17.9% immediately, and increment by an average of 38.1% one month after the HD-tDCS. These changes were not significant statistically (p-value >0.05). One patient experienced exacerbation of seizures during the stimulations hence dropped out of the study. Attention and working memory improved significantly immediately and one month after the HD-tDCS in all patients. Changes of EDs and mean seizure frequency caused by HD-tDCS were not statistically significant for the whole group; however, this method could improve the patients' working memory scores. Copyright © 2017 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

Hd3a and RFT1 are essential for flowering in rice.

PubMed

Komiya, Reina; Ikegami, Akiko; Tamaki, Shojiro; Yokoi, Shuji; Shimamoto, Ko

2008-02-01

RICE FLOWERING LOCUS T 1 (RFT1/FT-L3) is the closest homologue of Heading date 3a (Hd3a), which is thought to encode a mobile flowering signal and promote floral transition under short-day (SD) conditions. RFT1 is located only 11.5 kb from Hd3a on chromosome 6. Although RFT1 RNAi plants flowered normally, double RFT1-Hd3a RNAi plants did not flower up to 300 days after sowing (DAS), indicating that Hd3a and RFT1 are essential for flowering in rice. RFT1 expression was very low in wild-type plants, but there was a marked increase in RFT1 expression by 70 DAS in Hd3a RNAi plants, which flowered 90 DAS. H3K9 acetylation around the transcription initiation site of the RFT1 locus had increased by 70 DAS but not at 35 DAS. In the absence of Hd3a and RFT1 expression, transcription of OsMADS14 and OsMADS15, two rice orthologues of Arabidopsis APETALA1, was strongly reduced, suggesting that they act downstream of Hd3a and RFT1. These results indicate that Hd3a and RFT1 act as floral activators under SD conditions, and that RFT1 expression is partly regulated by chromatin modification.

Optical spectroscopy of X-Mega targets - V. The spectroscopic binary HD 93161 A and its visual companion HD 93161 B*

NASA Astrophysics Data System (ADS)

Nazé, Y.; Antokhin, I. I.; Sana, H.; Gosset, E.; Rauw, G.

2005-05-01

We present the analysis of an extensive set of high-resolution spectroscopic observations of HD 93161, a visual binary with a separation of 2 arcsec. HD 93161 A is a spectroscopic binary, with both components clearly detected throughout the orbit. The primary star is most probably of spectral type O8V, while the secondary is likely an O9V. We obtain the first orbital solution for this system, characterized by a period of 8.566 +/- 0.004 d. The minimum masses of the primary and secondary stars are 22.2 +/- 0.6 and 17.0 +/- 0.4 Msolar, respectively. These values are quite large, suggesting a high inclination of the orbit. The second object, HD 93161 B, displays an O6.5V(f) spectral type and is thus slightly hotter than its neighbour. This star is at first sight single but presents radial velocity variations. Finally, we study HD 93161 in the X-ray domain. No significant variability is detected. The X-ray spectrum is well described by a 2T model with kT1~ 0.3 keV and kT2~ 0.7 keV. The X-ray luminosity is rather moderate, without any large emission excess imputable to a wind interaction.

Abscisic acid-dependent regulation of small rubber particle protein gene expression in Taraxacum brevicorniculatum is mediated by TbbZIP1.

PubMed

Fricke, Julia; Hillebrand, Andrea; Twyman, Richard M; Prüfer, Dirk; Schulze Gronover, Christian

2013-04-01

Natural rubber is a high-molecular-mass biopolymer found in the latex of >2,500 plant species, including Hevea brasiliensis, Parthenium argentatum and Taraxacum spp. The active sites of rubber biosynthesis are rubber particles, which comprise a hydrophobic rubber core surrounded by a phospholipid monolayer membrane containing species-dependent lipids and associated proteins. Small rubber particle proteins are the most abundant rubber particle-associated proteins in Taraxacum brevicorniculatum (TbSRPPs) and may promote rubber biosynthesis by stabilizing the rubber particle architecture. We investigated the transcriptional regulation of genes encoding SRPPs and identified a bZIP transcription factor (TbbZIP.1) similar to the Arabidopsis thaliana ABI5-ABF-AREB subfamily, which is thought to include downstream targets of ABA and/or abiotic stress-inducible protein kinases. The TbbZIP.1 gene was predominantly expressed in laticifers and regulates the expression of TbSRPP genes in an ABA-dependent manner. The individual TbSRPP genes showed distinct induction profiles, suggesting diverse roles in rubber biosynthesis and stress adaptation. The potential involvement of TbSRPPs in the adaptation of T. brevicorniculatum plants to environmental stress is discussed based on our current knowledge of the stress-response roles of SRPPs and their homologs, and the protective function of latex and rubber against pathogens. Our data suggest that TbSRPPs contribute to stress tolerance in T. brevicorniculatum and that their effects are mediated by TbbZIP.1.

HD 129333: The Sun in its infancy

NASA Technical Reports Server (NTRS)

Dorren, J. David; Guinan, Edward F.

1994-01-01

HD 129333 is a remarkable young, nearby solar-type G star which offers a unique opportunity of studying the properties of the Sun at a time very shortly after in arrived on the main sequence. Its space motion suggest that it is a member of the Pleiades moving group, with an age of approximately 70 Myr; its lithium abundance is consistent with this. HD 129333 has the highest level of Ca II emission of any G star which is not a member of a close binary. Our observations in 1983 showed it to have low-amplitude (5%) light variations implying a rotation period of about 2.7 days, or about 10 times faster than the Sun. Modeling of the photometric variations on the assumption that they are due to starspots yields a spot temperature about 500 K cooler than the photosphere, and a coverage of about 6% of the stellar surface area. ROSAT observations in 1990 revealed the star to be an X-ray source, with an X-ray luminosity in the 0.2 to 2.4 keV range about 300 times that of the Sun. We have used International Ultraviolet Explorer (IUE) observations in conjuction with ground-based photometry to examine the magnetic activity of this star. The IUE emission-line fluxes reveal a level of chromospheric activity 3 to 20 times greater than the Sun's. The transition-region activity is 20 to 100 times that of the Sun. The activity level of HD 129333 is consistent with the Skumanich law relating activity to age, and with the rotation-activity relation, although it may be near saturation level. This star can yield valuable information about the magnetic dynamo of the young Sun, as well as about stellar dynamos in general. The 1988 IUE observations covered four phases of its rotational cycle. A phase dependence of the Mg II h and k emission flux suggests a close association of chromospheric plages with starspot regions at that time. Systematic variations in the mean brightness of HD 129333 between 1983 and 1993, and in the UV emission fluxes, indicate the presence of an activity cycle of an

Hyperglycemia-Induced Changes in ZIP7 and ZnT7 Expression Cause Zn2+ Release From the Sarco(endo)plasmic Reticulum and Mediate ER Stress in the Heart.

PubMed

Tuncay, Erkan; Bitirim, Verda C; Durak, Aysegul; Carrat, Gaelle R J; Taylor, Kathryn M; Rutter, Guy A; Turan, Belma

2017-05-01

Changes in cellular free Zn 2+ concentration, including those in the sarco(endo)plasmic reticulum [S(E)R], are primarily coordinated by Zn 2+ transporters (ZnTs) whose identity and role in the heart are not well established. We hypothesized that ZIP7 and ZnT7 transport Zn 2+ in opposing directions across the S(E)R membrane in cardiomyocytes and that changes in their activity play an important role in the development of ER stress during hyperglycemia. The subcellular S(E)R localization of ZIP7 and ZnT7 was determined in cardiomyocytes and in isolated S(E)R preparations. Markedly increased mRNA and protein levels of ZIP7 were observed in ventricular cardiomyocytes from diabetic rats or high-glucose-treated H9c2 cells while ZnT7 expression was low. In addition, we observed increased ZIP7 phosphorylation in response to high glucose in vivo and in vitro. By using recombinant-targeted Förster resonance energy transfer sensors, we show that hyperglycemia induces a marked redistribution of cellular free Zn 2+ , increasing cytosolic free Zn 2+ and lowering free Zn 2+ in the S(E)R. These changes involve alterations in ZIP7 phosphorylation and were suppressed by small interfering RNA-mediated silencing of CK2α. Opposing changes in the expression of ZIP7 and ZnT7 were also observed in hyperglycemia. We conclude that subcellular free Zn 2+ redistribution in the hyperglycemic heart, resulting from altered ZIP7 and ZnT7 activity, contributes to cardiac dysfunction in diabetes. © 2017 by the American Diabetes Association.

Cryogenic Characterization of FBK RGB-HD SiPMs

DOE PAGES

Aalseth, C. E.

2017-09-26

We report on the cryogenic characterization of Red Green Blue - High Density (RGB-HD) SiPMs developed at Fondazione Bruno Kessler (FBK) as part of the DarkSide program of dark matter searches with liquid argon time projection chambers. A dedicated setup was used to measure the primary dark noise, the correlated noise, and the gain of the SiPMs at varying temperatures. A custom-made data acquisition system and analysis software were used to precisely characterize these parameters. We demonstrate that FBK RGB-HD SiPMs with low quenching resistance (RGB-HD-LRmore » $$_q$$) can be operated from 40 K to 300 K with gains in the range $10^5$ to $10^6$ and noise rates on the order of a few Hz/mm$^2$.« less

76 FR 75939 - ZipGlobal Holdings, Inc., Symbollon Pharmaceuticals, Inc., Microholdings US, Inc., ComCam...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-05

... SECURITIES AND EXCHANGE COMMISSION [ File No. 500-1] ZipGlobal Holdings, Inc., Symbollon Pharmaceuticals, Inc., Microholdings US, Inc., ComCam International, Inc., Outfront Companies, Augrid Global... periodic reports since the period ended March 31, 2011. 3. Microholdings US, Inc. is an Oklahoma...

Involvement of auxin and a homeodomain-leucine zipper I gene in rhizoid development of the moss Physcomitrella patens.

PubMed

Sakakibara, Keiko; Nishiyama, Tomoaki; Sumikawa, Naomi; Kofuji, Rumiko; Murata, Takashi; Hasebe, Mitsuyasu

2003-10-01

Differentiation of epidermal cells is important for plants because they are in direct contact with the environment. Rhizoids are multicellular filaments that develop from the epidermis in a wide range of plants, including pteridophytes, bryophytes, and green algae; they have similar functions to root hairs in vascular plants in that they support the plant body and are involved in water and nutrient absorption. In this study, we examined mechanisms underlying rhizoid development in the moss, Physcomitrella patens, which is the only land plant in which high-frequency gene targeting is possible. We found that rhizoid development can be split into two processes: determination and differentiation. Two types of rhizoids with distinct developmental patterns (basal and mid-stem rhizoids) were recognized. The development of basal rhizoids from epidermal cells was induced by exogenous auxin, while that of mid-stem rhizoids required an unknown factor in addition to exogenous auxin. Once an epidermal cell had acquired a rhizoid initial cell fate, expression of the homeodomain-leucine zipper I gene Pphb7 was induced. Analysis of Pphb7 disruptant lines showed that Pphb7 affects the induction of pigmentation and the increase in the number and size of chloroplasts, but not the position or number of rhizoids. This is the first report on the involvement of a homeodomain-leucine zipper I gene in epidermal cell differentiation.

Cometary Dust in the Debris Disks of HD 31648 and HD 163296: Two "Baby" (BETA) Pictoris Stars

NASA Technical Reports Server (NTRS)

Sitko, Michael L.; Grady, Carol A.; Lynch, David K.; Russell, Ray W.; Hanner, Martha S.; Hanner, Martha S.

1999-01-01

The debris disks surrounding the pre-main-sequence stars HD 31648 and HD 163296 were observed spectroscopically between 3 and 14 microns. Both stars possess a silicate emission feature at 10 microns that resembles that of the star beta Pictoris and those observed in solar system comets. The structure of the band is consistent with a mixture of olivine and pyroxene material, plus an underlying continuum of unspecified origin. The similarity in both size and structure of the silicate band suggests that the material in these systems had a processing history similar to that in our own solar system prior to the time that the grains were incorporated into comets.

The Perennial Ryegrass GenomeZipper: Targeted Use of Genome Resources for Comparative Grass Genomics1[C][W

PubMed Central

Pfeifer, Matthias; Martis, Mihaela; Asp, Torben; Mayer, Klaus F.X.; Lübberstedt, Thomas; Byrne, Stephen; Frei, Ursula; Studer, Bruno

2013-01-01

Whole-genome sequences established for model and major crop species constitute a key resource for advanced genomic research. For outbreeding forage and turf grass species like ryegrasses (Lolium spp.), such resources have yet to be developed. Here, we present a model of the perennial ryegrass (Lolium perenne) genome on the basis of conserved synteny to barley (Hordeum vulgare) and the model grass genome Brachypodium (Brachypodium distachyon) as well as rice (Oryza sativa) and sorghum (Sorghum bicolor). A transcriptome-based genetic linkage map of perennial ryegrass served as a scaffold to establish the chromosomal arrangement of syntenic genes from model grass species. This scaffold revealed a high degree of synteny and macrocollinearity and was then utilized to anchor a collection of perennial ryegrass genes in silico to their predicted genome positions. This resulted in the unambiguous assignment of 3,315 out of 8,876 previously unmapped genes to the respective chromosomes. In total, the GenomeZipper incorporates 4,035 conserved grass gene loci, which were used for the first genome-wide sequence divergence analysis between perennial ryegrass, barley, Brachypodium, rice, and sorghum. The perennial ryegrass GenomeZipper is an ordered, information-rich genome scaffold, facilitating map-based cloning and genome assembly in perennial ryegrass and closely related Poaceae species. It also represents a milestone in describing synteny between perennial ryegrass and fully sequenced model grass genomes, thereby increasing our understanding of genome organization and evolution in the most important temperate forage and turf grass species. PMID:23184232

NASA Releases 'NASA App HD' for iPad

NASA Image and Video Library

2012-07-06

The NASA App HD invites you to discover a wealth of NASA information right on your iPad. The application collects, customizes and delivers an extensive selection of dynamically updated mission information, images, videos and Twitter feeds from various online NASA sources in a convenient mobile package. Come explore with NASA, now on your iPad. 2012 Updated Version - HD Resolution and new features. Original version published on Sept. 1, 2010.

Outpatient screening of Japanese children with epilepsy for attention-deficit/hyperactivity disorder (AD/HD).

PubMed

Tanabe, Takuya; Kashiwagi, Mitsuru; Shimakawa, Shuichi; Tamai, Hiroshi; Wakamiya, Eiji

2014-04-01

The significance of the Strengths and Difficulties Questionnaire (SDQ) score for AD/HD (attention-deficit/hyperactivity disorder) screening was assessed in Japanese epileptic children. Sixty-eight epileptic children were enrolled in this study. Parents were asked to fill out both the SDQ and AD/HD-rating scale (AD/HD-RS) simultaneously. The SDQ subscale of hyperactivity showed the highest score. The AD/HD-RS showed higher scores for both inattention and hyperactivity-impulsivity. Twenty-two (32.4%) of these subjects were diagnosed as having AD/HD. The SDQ subscale for hyperactivity showed 86.4% sensitivity and 95% specificity, respectively, for detection of AD/HD. All SDQ subscales correlated significantly with inattention and hyperactivity-impulsivity scores of the AD/HD-RS. The SDQ is a good screening tool which can contribute to the detection of AD/HD, not only of the hyperactive/impulsive but also the inattentive subtype. Furthermore, the SDQ can elucidate more complicated behavioral problems than the core symptoms of AD/HD that are not noticed in the epilepsy clinic. Copyright © 2013 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

Determining Market Categorization of United States Zip Codes for Purposes of Army Recruiting

DTIC Science & Technology

2016-06-01

NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA THESIS Approved for public release; distribution is unlimited DETERMINING MARKET ...2016 3. REPORT TYPE AND DATES COVERED Master’s thesis 4. TITLE AND SUBTITLE DETERMINING MARKET CATEGORIZATION OF UNITED STATES ZIP CODES FOR...Army uses commercial market segmentation data to analyze markets and past accessions to assign recruiters and quotas to maximize production. We use

Prevalence and determinants of fatigue in patients with moderate to severe chronic GvHD.

PubMed

Im, A; Mitchell, S A; Steinberg, S M; Curtis, L; Berger, A; Baird, K; Kuzmina, Z; Joe, G; Comis, L E; Juckett, M; Avila, D; Baruffaldi, J; Masuch, L; Pirsl, F; Pavletic, S Z

2016-05-01

Although fatigue is common after allogeneic hematopoietic cell transplantation, little is known about fatigue in patients with chronic GvHD (cGvHD). The aim of this study was to explore factors associated with fatigue in cGvHD. Data were drawn from a sequentially recruited, cross-sectional study of adults with moderate or severe cGvHD (n=263). Respondents were classified as fatigued or not fatigued based on their response to a single item regarding loss of energy from the Lee cGvHD Symptom Scale. In univariate analysis, factors significantly associated with fatigue included performance status, number of prior cGvHD therapies, cGvHD symptom bother, self-assessed physical and mental health, nutritional status, walk velocity and self-reported physical activity. There were no significant associations between fatigue and disease-related cGvHD variables. Multivariable logistic regression demonstrated that being less active and having pulmonary and/or muscle/joint symptoms were independently associated with fatigue. In conclusion, clinically significant fatigue was prevalent in more than one-third of subjects with cGvHD, and was disabling. Absence of association with measures of cGvHD severity underscores the need to elucidate the pathogenesis of fatigue and its relationship with inflammatory activity. Pulmonary and muscle/joint symptoms and physical inactivity represent potential targets for intervention in clinical studies.

Expression of apoptosis related proteins: RAIDD, ZIP kinase, Bim/BOD, p21, Bax, Bcl-2 and NF-kappaB in brains of patients with Down syndrome.

PubMed

Engidawork, E; Gulesserian, T; Seidl, R; Cairns, N; Lubec, G

2001-01-01

Down syndrome (DS) is a genetic disease that exhibits significant neuropathological parallels with Alzheimer's disease (AD). One of the features of DS, neuronal loss, has been hypothesized to occur as a result of apoptosis. An increasing number of proteins are implicated in apoptosis and several of them were shown to be altered in AD, however, the knowledge in DS is far from complete. To further substantiate the hypothesis that apoptosis is the underlying mechanism for neuronal loss and contribute towards the current knowledge of apoptosis in DS, we analyzed the expression of apoptosis related proteins in frontal cortex and cerebellum of DS by western blot and ELISA techniques. Quantitative analysis revealed a significant increase in DS frontal (P < 0.0001) and cerebellar (P < 0.05) Bim/BOD (Bcl-2 interacting mediator of cell death/Bcl-2 related ovarian death gene), cerebellar Bcl-2 (P < 0.01) as well as p21 (P < 0.05) levels compared to controls. No significant change was detected in Bax, RAIDD (receptor interacting protein (RIP)-associated ICH-1/CED-3-homologus protein with death domain), ZIP (Zipper interacting protein) kinase and NF-kappaB p65 levels in both regions, although frontal cortex levels of RAIDD, Bcl-2 and p21 levels tended to increase. In addition, a 45 kDa truncated form of NF-kappaB p65 displayed a significant elevation (P < 0.05) in DS cerebellum. No significant correlation had been obtained between postmortem interval and level of the proteins analyzed. With regard to age, it was only NF-kappaB p65 that showed significant correlation (r = -0.8964, P = 0.0155, n = 9) in frontal cortex of controls. These findings provide further evidence that apoptosis indeed accounts for the neuronal loss in DS but Bax and RAIDD do not appear to take part in this process.

VizieR Online Data Catalog: Radial velocities of HD 133131A and HD 133131B (Teske+, 2016)

NASA Astrophysics Data System (ADS)

Teske, J. K.; Shectman, S. A.; Vogt, S. S.; Diaz, M.; Butler, R. P.; Crane, J. D.; Thompson, I. B.; Arriagada, P.

2017-05-01

The radial velocity observations of HD133131A and B are part of the large Magellan Planet Search Program, which began in 2002 and is surveying a sample of ~500 of the nearest stars (<100pc). The survey was started with observations from the Magellan Inamori Kyocera Echelle (MIKE) echelle spectrograph, mounted for a limited time on the Magellan I (Baade), but mostly on Magellan II (Clay), 6.5m telescopes at Las Campanas Observatory. In 2010, the survey switched to using the Carnegie Planet Finder Spectrograph (PFS), a temperature-controlled high-resolution echelle spectrograph built for precision radial velocity observations, on Magellan II. Only HD133131A observations from MIKE are included here. Using a 0.35*5'' slit, MIKE provides spectra with R~70000 in the blue and ~50000 in the red and covers 3900-6200Å. Only the red MIKE orders are used for radial velocity determination, while the blue orders provide coverage of the CaIIH and K lines for monitoring stellar activity. The MIKE observations of HD133131A span 2003 June to 2009 July, with total exposure times ranging from 150 to 600s, depending on observing conditions. Both HD133131A and B were observed with PFS, the former observations ranging from 2010 February to 2015 September, and the latter from 2010 August to 2015 September. PFS has a more limited wavelength range than MIKE (3880-6680Å), but still covers the entire iodine wavelength region, CaIIH and K, and Hα. We use a 0.5*2.5'' slit for target observations, providing R~80000 in the iodine region. The total exposure times for the A component range from 285 to 720s, and for the B component range from 282 to 800s. (6 data files).

Cutaneous Uptake of 14C-HD Vapor by the Hairless Guinea Pig.

DTIC Science & Technology

1996-10-01

guinea pig (HGP) is used by our laboratory to model the human cutaneous response to sulfur mustard (HD) exposure. We have determined the HD content in the skin of HOP after 7-minute exposures to vapors saturated with a mixture of HD and 14C-HD. Concentration/time (C1) values in the range of 2 mg/sq cm/min were determined by counting skin 14C disintegrations per minute (dpm) in animals euthanized immediately after exposure. These values are similar to human penetration rates obtained by other investigators. A direct relationship between C1 and relative humidity was

HD-DVD: the next consumer electronics revolution?

NASA Astrophysics Data System (ADS)

Topiwala, Pankaj N.

2003-11-01

The DVD is emerging as one of the world's favorite consumer electronics product, rapidly replacing analog videotape in the US and many other markets at prodigious rates. It is capable of offering a full feature-length, standard-definition movie in crisp rendition on TV. TV technology is itself in the midst of switching from analog to digital TV, with high-definition being the main draw. In fact, the US government has been advocating that switch over to digital TC, with both carrot and stick approaches, for nearly two decades, with only modest results--about 2% penetration. Under FCC herding, broadcasters are falling in the digital line--slowly, and sans profit. Meanwhile, delivery of HD content on portable media would be a great solution. Indeed, a new disk technology based on blue lasers is coming; but its widespread adoption may yet be four to five yeras away. But a promising new video codec--H.264/MPEG-4 AVC, the latest coding standard jointly developed by the Video Coding Experts Group (VCEG) of ITU-T and Moving Picture Experts Group (MPEG) of ISO/IEC, just might be the missing link. It offers substantial coding gains over MPEG-2, used in today's DVDs. With H.264, it appears possible to put HD movies on today's red-laser DVDs. Since consumers love DVDs, and HD--when they can see it, can H.264 and HD-DVD ignite a new revolution, now? It may have a huge impact on (H)DTV adoption rates.

Evidences of extragalactic origin and planet engulfment in the metal-poor twin pair HD 134439/HD 134440

NASA Astrophysics Data System (ADS)

Reggiani, Henrique; Meléndez, Jorge

2018-04-01

Recent studies of chemical abundances in metal-poor halo stars show the existence of different populations, which is important for studies of Galaxy formation and evolution. Here, we revisit the twin pair of chemically anomalous stars HD 134439 and HD 134440, using high resolution (R ˜ 72 000) and high S/N ratio (S/N ˜ 250) HDS/Subaru spectra. We compare them to the well-studied halo star HD 103095, using the line-by-line differential technique to estimate precise stellar parameters and LTE chemical abundances. We present the abundances of C, O, Na, Mg, Si, Ca, Sc, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Sr, Y, Ba, La, Ce, Nd, and Sm. We compare our results to the precise abundance patterns of Nissen & Schuster (2010) and data from dwarf Spheroidal galaxies (dSphs). We show that the abundance pattern of these stars appears to be closely linked to that of dSphs with [α/Fe] knee below [Fe/H] < -1.5. We also find a systematic difference of 0.06 ± 0.01 dex between the abundances of these twin binary stars, which could be explained by the engulfment of a planet, thus suggesting that planet formation is possible at low metallicities ([Fe/H] = -1.4).

The Blue Needle: A Highly Asymmetric Debris Disk Surrounding HD 15115

NASA Astrophysics Data System (ADS)

Kalas, P.; Graham, J. R.; Fitzgerald, M.

2007-06-01

Using the ACS coronagraph aboard the Hubble Space Telescope in the optical, and Keck adaptive optics in the near- infrared, we discovered an edge-on dust disk surrounding the F2V star HD 15115. HD 15115 is the most asymmetric debris disk imaged to date, with an eastward pointing midplane detected to ~315 AU radius, and a westward pointing midplane detected to >550 AU radius. The blue optical to near-infrared scattered light color relative to the star may indicate dust scattering properties similar to the AU Mic debris disk. The existence of a large debris disk surrounding HD 15115 is consistent with its proposed membership in the Beta Pic moving group, and the extreme asymmetry presents significant theoretical challenges. We hypothesize that the extreme asymmetries may be caused by dynamical perturbations from HIP 12545, another Beta Pic Moving Group member east of HD 15115, that shares a common proper motion vector, heliocentric distance, Galactic space velocity, and age. HD 15115 is a prime candidate for exoplanet detection via radial velocity and transit techniques.

Abundance study of the two solar-analogue CoRoT targets HD 42618 and HD 43587 from HARPS spectroscopy

NASA Astrophysics Data System (ADS)

Morel, T.; Rainer, M.; Poretti, E.; Barban, C.; Boumier, P.

2013-04-01

We present a detailed abundance study based on spectroscopic data obtained with HARPS of two solar-analogue main targets for the asteroseismology programme of the CoRoT satellite: HD 42618 and HD 43587. The atmospheric parameters and chemical composition are accurately determined through a fully differential analysis with respect to the Sun observed with the same instrumental set-up. Several sources of systematic errors largely cancel out with this approach, which allows us to narrow down the 1-σ error bars to typically 20 K in effective temperature, 0.04 dex in surface gravity, and less than 0.05 dex in the elemental abundances. Although HD 42618 fulfils many requirements for being classified as a solar twin, its slight deficiency in metals and its possibly younger age indicate that, strictly speaking, it does not belong to this class of objects. On the other hand, HD 43587 is slightly more massive and evolved. In addition, marked differences are found in the amount of lithium present in the photospheres of these two stars, which might reveal different mixing properties in their interiors. These results will put tight constraints on the forthcoming theoretical modelling of their solar-like oscillations and contribute to increase our knowledge of the fundamental parameters and internal structure of stars similar to our Sun. Based on observations collected at the La Silla Observatory, ESO (Chile) with the HARPS spectrograph at the 3.6-m telescope, under programme LP185.D-0056.Tables 1 and 2 are available in electronic form at http://www.aanda.org

Hexokinase 1 is required for glucose-induced repression of bZIP63, At5g22920, and BT2 in Arabidopsis

DOE PAGES

Kunz, Sabine; Gardestrom, Per; Pesquet, Edouard; ...

2015-07-14

Simple sugars, like glucose (Glc) and sucrose (Suc), act as signals to modulate the expression of hundreds of genes in plants. Frequently, however, it remains unclear whether this regulation is induced by the sugars themselves or by their derivatives generated in the course of carbohydrate (CH) metabolism. In the present study, we tested the relevance of different CH metabolism and allocation pathways affecting expression patterns of five selected sugar-responsive genes ( bZIP63, At5g22920, BT2, MGD2, and TPS9) in Arabidopsis thaliana. In general, the expression followed diurnal changes in the overall sugar availability. However, under steady growth conditions, this response wasmore » hardly impaired in the mutants for CH metabolizing/ transporting proteins ( adg1, sex1, sus1-4, sus5/6, and tpt2), including also hexokinase1 (HXK1) loss- and gain-of-function plants— gin2.1 and oe3.2, respectively. In addition, transgenic plants carrying pbZIP63::GUS showed no changes in reporter-gene-expression when grown on sugar under steady-state conditions. In contrast, short-term treatments of agar-grown seedlings with 1% Glc or Suc induced pbZIP63::GUS repression, which became even more apparent in seedlings grown in liquid media. Subsequent analyses of liquid-grown gin2.1 and oe3.2 seedlings revealed that Glc -dependent regulation of the five selected genes was not affected in gin2.1, whereas it was enhanced in oe3.2 plants for bZIP63, At5g22920, and BT. The sugar treatments had no effect on ATP/ADP ratio, suggesting that changes in gene expression were not linked to cellular energy status. Altogether, the data suggest that HXK1 does not act as Glc sensor controlling bZIP63, At5g22920, and BT2 expression, but it is nevertheless required for the production of a downstream metabolic signal regulating their expression« less

Hexokinase 1 is required for glucose-induced repression of bZIP63, At5g22920, and BT2 in Arabidopsis

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

Kunz, Sabine; Gardestrom, Per; Pesquet, Edouard

Simple sugars, like glucose (Glc) and sucrose (Suc), act as signals to modulate the expression of hundreds of genes in plants. Frequently, however, it remains unclear whether this regulation is induced by the sugars themselves or by their derivatives generated in the course of carbohydrate (CH) metabolism. In the present study, we tested the relevance of different CH metabolism and allocation pathways affecting expression patterns of five selected sugar-responsive genes ( bZIP63, At5g22920, BT2, MGD2, and TPS9) in Arabidopsis thaliana. In general, the expression followed diurnal changes in the overall sugar availability. However, under steady growth conditions, this response wasmore » hardly impaired in the mutants for CH metabolizing/ transporting proteins ( adg1, sex1, sus1-4, sus5/6, and tpt2), including also hexokinase1 (HXK1) loss- and gain-of-function plants— gin2.1 and oe3.2, respectively. In addition, transgenic plants carrying pbZIP63::GUS showed no changes in reporter-gene-expression when grown on sugar under steady-state conditions. In contrast, short-term treatments of agar-grown seedlings with 1% Glc or Suc induced pbZIP63::GUS repression, which became even more apparent in seedlings grown in liquid media. Subsequent analyses of liquid-grown gin2.1 and oe3.2 seedlings revealed that Glc -dependent regulation of the five selected genes was not affected in gin2.1, whereas it was enhanced in oe3.2 plants for bZIP63, At5g22920, and BT. The sugar treatments had no effect on ATP/ADP ratio, suggesting that changes in gene expression were not linked to cellular energy status. Altogether, the data suggest that HXK1 does not act as Glc sensor controlling bZIP63, At5g22920, and BT2 expression, but it is nevertheless required for the production of a downstream metabolic signal regulating their expression« less

The Zinc Concentration in the Diet and the Length of the Feeding Period Affect the Methylation Status of the ZIP4 Zinc Transporter Gene in Piglets

PubMed Central

Karweina, Diana; Kreuzer-Redmer, Susanne; Müller, Uwe; Franken, Tobias; Pieper, Robert; Baron, Udo; Olek, Sven; Zentek, Jürgen; Brockmann, Gudrun A.

2015-01-01

High doses of zinc oxide are commonly used in weaned pig diets to improve performance and health. Recent reports show that this may also lead to an imbalanced zinc homeostasis in the animal. For a better understanding of the regulatory mechanisms of different zinc intakes, we performed a feeding experiment to assess potential epigenetic regulation of the ZIP4 gene expression via DNA methylation in the small intestine of piglets. Fifty-four piglets were fed diets with 57 (LZn), 164 (NZn) or 2,425 (HZn) mg Zn/kg feed for one or four weeks. The ZIP4 expression data provided significant evidence for counter-regulation of zinc absorption with higher dietary zinc concentrations. The CpG +735 in the second exon had a 56% higher methylation in the HZn group compared to the others after one week of feeding (8.0·10-4 < p < 0.035); the methylation of this CpG was strongly negatively associated with the expression of the long ZIP4 transcripts (p < 0.007). In the LZn and NZn diets, the expression of the long ZIP4 transcripts were lower after four vs. one week of feeding (2.9·10-4 < p < 0.017). The strongest switch leading to high DNA methylation in nearly all analysed regions was dependent on feeding duration or age in all diet groups (3.7·10-10 < p < 0.099). The data suggest that DNA methylation serves as a fine-tuning mechanism of ZIP4 gene regulation to maintain zinc homeostasis. Methylation of the ZIP4 gene may play a minor role in the response to very high dietary zinc concentration, but may affect binding of alternate zinc-responsive transcription factors. PMID:26599865

Precise masses for the transiting planetary system HD 106315 with HARPS

NASA Astrophysics Data System (ADS)

Barros, S. C. C.; Gosselin, H.; Lillo-Box, J.; Bayliss, D.; Delgado Mena, E.; Brugger, B.; Santerne, A.; Armstrong, D. J.; Adibekyan, V.; Armstrong, J. D.; Barrado, D.; Bento, J.; Boisse, I.; Bonomo, A. S.; Bouchy, F.; Brown, D. J. A.; Cochran, W. D.; Collier Cameron, A.; Deleuil, M.; Demangeon, O.; Díaz, R. F.; Doyle, A.; Dumusque, X.; Ehrenreich, D.; Espinoza, N.; Faedi, F.; Faria, J. P.; Figueira, P.; Foxell, E.; Hébrard, G.; Hojjatpanah, S.; Jackman, J.; Lendl, M.; Ligi, R.; Lovis, C.; Melo, C.; Mousis, O.; Neal, J. J.; Osborn, H. P.; Pollacco, D.; Santos, N. C.; Sefako, R.; Shporer, A.; Sousa, S. G.; Triaud, A. H. M. J.; Udry, S.; Vigan, A.; Wyttenbach, A.

2017-12-01

Context. The multi-planetary system HD 106315 was recently found in K2 data. The planets have periods of Pb 9.55 and Pc 21.06 days, and radii of rb = 2.44 ± 0.17 R⊕ and rc = 4.35 ± 0.23 R⊕ . The brightness of the host star (V = 9.0 mag) makes it an excellent target for transmission spectroscopy. However, to interpret transmission spectra it is crucial to measure the planetary masses. Aims: We obtained high precision radial velocities for HD 106315 to determine the mass of the two transiting planets discovered with Kepler K2. Our successful observation strategy was carefully tailored to mitigate the effect of stellar variability. Methods: We modelled the new radial velocity data together with the K2 transit photometry and a new ground-based partial transit of HD 106315c to derive system parameters. Results: We estimate the mass of HD 106315b to be 12.6 ± 3.2 M⊕ and the density to be 4.7 ± 1.7 g cm-3, while for HD 106315c we estimate a mass of 15.2 ± 3.7 M⊕ and a density of 1.01 ± 0.29 g cm-3. Hence, despite planet c having a radius almost twice as large as planet b, their masses are consistent with one another. Conclusions: We conclude that HD 106315c has a thick hydrogen-helium gaseous envelope. A detailed investigation of HD 106315b using a planetary interior model constrains the core mass fraction to be 5-29%, and the water mass fraction to be 10-50%. An alternative, not considered by our model, is that HD 106315b is composed of a large rocky core with a thick H-He envelope. Transmission spectroscopy of these planets will give insight into their atmospheric compositions and also help constrain their core compositions. Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under ESO programme 198.C-0168.

ALMA and VLA observations of the HD 141569 system

NASA Astrophysics Data System (ADS)

White, Jacob Aaron; Boley, A. C.; MacGregor, M. A.; Hughes, A. M.; Wilner, D. J.

2018-03-01

We present VLA 9 mm (33 GHz) and archival ALMA 2.9 mm (103 GHz) observations of the HD 141569 system. The VLA observations achieve a resolution of 0.25 arcsec (˜28 au) and a sensitivity of 4.7 μJy beam- 1. We find (1) a 52 ± 5 μJy point source at the location of HD 141569A that shows potential variability, (2) the detected flux is contained within the SED-inferred central clearing of the disc meaning the spectral index of the dust disc is steeper than previously inferred, and (3) the M dwarf companions are also detected and variable. Previous lower resolution VLA observations (semester 14A) found a higher flux density, interpreted as solely dust emission. When combined with ALMA observations, the VLA 14A observations suggested the spectral index, and grain size distribution of HD 141569's disc was shallow and an outlier among debris systems. Using archival ALMA observations of HD 141569 at 0.87 and 2.9 mm, we find a dust spectral index of αmm = 1.81 ± 0.20. The VLA 16A flux corresponds to a brightness temperature of ˜5 × 106 K, suggesting strong non-disc emission is affecting the inferred grain properties. The VLA 16A flux density of the M2V companion HD 141569B is 149 ± 9 μJy, corresponding to a brightness temperature of ˜2 × 108 K and suggesting significant stellar variability when compared to the VLA14A observations, which are smaller by a factor of ˜6.

Zinc Fortification Decreases ZIP1 Gene Expression of Some Adolescent Females with Appropriate Plasma Zinc Levels

PubMed Central

Méndez, Rosa O.; Santiago, Alejandra; Yepiz-Plascencia, Gloria; Peregrino-Uriarte, Alma B.; de la Barca, Ana M. Calderón; García, Hugo S.

2014-01-01

Zinc homeostasis is achieved after intake variation by changes in the expression levels of zinc transporters. The aim of this study was to evaluate dietary intake (by 24-h recall), absorption, plasma zinc (by absorption spectrophotometry) and the expression levels (by quantitative PCR), of the transporters ZIP1 (zinc importer) and ZnT1 (zinc exporter) in peripheral white blood cells from 24 adolescent girls before and after drinking zinc-fortified milk for 27 day. Zinc intake increased (p < 0.001) from 10.5 ± 3.9 mg/day to 17.6 ± 4.4 mg/day, and its estimated absorption from 3.1 ± 1.2 to 5.3 ± 1.3 mg/day. Mean plasma zinc concentration remained unchanged (p > 0.05) near 150 µg/dL, but increased by 31 µg/dL (p < 0.05) for 6/24 adolescents (group A) and decreased by 25 µg/dL (p < 0.05) for other 6/24 adolescents (group B). Expression of ZIP1 in blood leukocytes was reduced 1.4-fold (p < 0.006) in group A, while for the expression of ZnT1 there was no difference after intervention (p = 0.39). An increase of dietary zinc after 27-days consumption of fortified-milk did not increase (p > 0.05) the plasma level of adolescent girls but for 6/24 participants from group A in spite of the formerly appropriation, which cellular zinc uptake decreased as assessed by reduction of the expression of ZIP1. PMID:24922175

Extreme Population Differences in the Human Zinc Transporter ZIP4 (SLC39A4) Are Explained by Positive Selection in Sub-Saharan Africa

PubMed Central

Pybus, Marc; Andrews, Glen K.; Lalueza-Fox, Carles; Comas, David; Sekler, Israel; de la Rasilla, Marco; Rosas, Antonio; Stoneking, Mark; Valverde, Miguel A.; Vicente, Rubén; Bosch, Elena

2014-01-01

Extreme differences in allele frequency between West Africans and Eurasians were observed for a leucine-to-valine substitution (Leu372Val) in the human intestinal zinc uptake transporter, ZIP4, yet no further evidence was found for a selective sweep around the ZIP4 gene (SLC39A4). By interrogating allele frequencies in more than 100 diverse human populations and resequencing Neanderthal DNA, we confirmed the ancestral state of this locus and found a strong geographical gradient for the derived allele (Val372), with near fixation in West Africa. In extensive coalescent simulations, we show that the extreme differences in allele frequency, yet absence of a classical sweep signature, can be explained by the effect of a local recombination hotspot, together with directional selection favoring the Val372 allele in Sub-Saharan Africans. The possible functional effect of the Leu372Val substitution, together with two pathological mutations at the same codon (Leu372Pro and Leu372Arg) that cause acrodermatitis enteropathica (a disease phenotype characterized by extreme zinc deficiency), was investigated by transient overexpression of human ZIP4 protein in HeLa cells. Both acrodermatitis mutations cause absence of the ZIP4 transporter cell surface expression and nearly absent zinc uptake, while the Val372 variant displayed significantly reduced surface protein expression, reduced basal levels of intracellular zinc, and reduced zinc uptake in comparison with the Leu372 variant. We speculate that reduced zinc uptake by the ZIP4-derived Val372 isoform may act by starving certain pathogens of zinc, and hence may have been advantageous in Sub-Saharan Africa. Moreover, these functional results may indicate differences in zinc homeostasis among modern human populations with possible relevance for disease risk. PMID:24586184

Cummins MD & HD Accessory Hybridization CRADA -Annual Report FY15

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

Deter, Dean D.

2015-10-01

There are many areas of MD and HD vehicles that can be improved by new technologies and optimized control strategies. Component optimization and idle reduction need to be addressed, this is best done by a two part approach that includes selecting the best component technology, and/or architecture, and optimized controls that are vehicle focused. While this is a common focus in the light duty industry it has been gaining momentum in the MD and HD market as the market gets more competitive and the regulations become more stringent. When looking into systems optimization and idle reduction technologies, affected vehicle systemsmore » must first be considered, and if possible included in the new architecture to get the most benefit out of these new capabilities. Typically, when looking into idle reduction or component optimization for MD/HD, the vehicle s accessories become a prime candidate for electrification or hybridization. While this has already been studied on light duty vehicles (especially on hybrids and electric vehicles) it has not made any head way or market penetration in most MD and HD applications. If hybrids and electric MD and HD vehicles begin to break into the market this would be a necessary step into the ability to make those vehicles successful by allowing for independent, optimized operation separate from the engine.« less

The impact of reinforcement contingencies on AD/HD: a review and theoretical appraisal.

PubMed

Luman, Marjolein; Oosterlaan, Jaap; Sergeant, Joseph A

2005-02-01

One of the core deficits in attention deficit/hyperactivity disorder (AD/HD) is thought to be an aberrant sensitivity to reinforcement, such as reward and response cost. Twenty-two studies (N=1181 children) employing AD/HD and reinforcement contingencies are reviewed from vantage points: task performance, motivation, and psychophysiology. Results indicate that reinforcement contingencies have a positive impact on task performance and levels of motivation for both children with AD/HD and normal controls. There is evidence that the effect related to task performance is somewhat more prominent in AD/HD. There is some evidence that a high intensity of reinforcement is highly effective in AD/HD. Children with AD/HD prefer immediate over delayed reward. From a psychophysiological point of view, children with AD/HD seem less sensitive to reinforcement compared to controls. While comorbid disorders are suggested to be confounders of the dependent variables, many studies do not examine the effect of oppositional defiant disorder (ODD) and conduct disorder (CD). We discuss the implications of the findings for five theoretical frameworks, including the model by, the cognitive-energetic model (CEM), the dual-pathway model and the BIS/BAS model. Results show a discrepancy between the theoretical models and the behavioural findings.

Crystalens HD intraocular lens analysis using an adaptive optics visual simulator.

PubMed

Pérez-Vives, Cari; Montés-Micó, Robert; López-Gil, Norberto; Ferrer-Blasco, Teresa; García-Lázaro, Santiago

2013-12-01

To compare visual and optical quality of the Crystalens HD intraocular lens (IOL) with that of a monofocal IOL. The wavefront aberration patterns of the monocular Akreos Adapt AO IOL and the single-optic accommodating Crystalens HD IOL were measured in a model eye. The Crystalens IOL was measured in its nonaccommodative state and then, after flexing the haptic to produce 1.4 mm of movement, in its accommodative state. Using an adaptive optics system, subjects' aberrations were removed and replaced with those of pseudophakes viewing with either lens. Monocular distance visual acuity (DVA) at high (100%), medium (50%), and low (10%) contrast and contrast sensitivity (CS) were measured for both IOL optics. Near VA (NVA) and CS were measured for the Crystalens HD IOL in its accommodative state. Depth of focus around the distance and near focus was also evaluated for the Crystalens HD IOL. Modulation transfer function (MTF), point spread function (PSF), and Strehl ratio were also calculated. All measures were taken for 3- and 5-mm pupils. The MTF, PSF, and Strehl ratio showed comparable values between IOLs (p > 0.05). There were no significant differences in DVA and CS between IOLs for all contrasts and pupils (p > 0.05). When spherically focused, mean DVA and NVA with the Crystalens HD IOL were ≥20/20 at 100 and 50% contrasts for both pupils. Monocular DVA, NVA, and CS were slightly better with 3- than 5-mm pupils, but without statistically significant differences. The Crystalens HD IOL showed about 0.75 and 0.50 D of depth of focus in its accommodative state and nonaccommodative state, respectively. The optical and visual quality with the nonaccommodatied Crystalens HD IOL was comparable to that of a monofocal IOL. If this lens can move 1.4 mm in the eye, it will provide high-quality optics for near vision as well.

Growth Arrest by Trehalose-6-Phosphate: An Astonishing Case of Primary Metabolite Control over Growth by Way of the SnRK1 Signaling Pathway1[C][W][OA

PubMed Central

Delatte, Thierry L.; Sedijani, Prapti; Kondou, Youichi; Matsui, Minami; de Jong, Gerhardus J.; Somsen, Govert W.; Wiese-Klinkenberg, Anika; Primavesi, Lucia F.; Paul, Matthew J.; Schluepmann, Henriette

2011-01-01

The strong regulation of plant carbon allocation and growth by trehalose metabolism is important for our understanding of the mechanisms that determine growth and yield, with obvious applications in crop improvement. To gain further insight on the growth arrest by trehalose feeding, we first established that starch-deficient seedlings of the plastidic phosphoglucomutase1 mutant were similarly affected as the wild type on trehalose. Starch accumulation in the source cotyledons, therefore, did not cause starvation and consequent growth arrest in the growing zones. We then screened the FOX collection of Arabidopsis (Arabidopsis thaliana) expressing full-length cDNAs for seedling resistance to 100 mm trehalose. Three independent transgenic lines were identified with dominant segregation of the trehalose resistance trait that overexpress the bZIP11 (for basic region/leucine zipper motif) transcription factor. The resistance of these lines to trehalose could not be explained simply through enhanced trehalase activity or through inhibition of bZIP11 translation. Instead, trehalose-6-phosphate (T6P) accumulation was much increased in bZIP11-overexpressing lines, suggesting that these lines may be insensitive to the effects of T6P. T6P is known to inhibit the central stress-integrating kinase SnRK1 (KIN10) activity. We confirmed that this holds true in extracts from seedlings grown on trehalose, then showed that two independent transgenic lines overexpressing KIN10 were insensitive to trehalose. Moreover, the expression of marker genes known to be jointly controlled by SnRK1 activity and bZIP11 was consistent with low SnRK1 or bZIP11 activity in seedlings on trehalose. These results reveal an astonishing case of primary metabolite control over growth by way of the SnRK1 signaling pathway involving T6P, SnRK1, and bZIP11. PMID:21753116

The sunflower transcription factor HaHB11 confers tolerance to water deficit and salinity to transgenic Arabidopsis and alfalfa plants.

PubMed

Cabello, Julieta V; Giacomelli, Jorge I; Gómez, María C; Chan, Raquel L

2017-09-10

Homeodomain-leucine zipper (HD-Zip) transcription factors are unique to the plant kingdom; members of subfamily I are known to be involved in abiotic stress responses. HaHB11 belongs to this subfamily and it was previously shown that it is able to confer improved yield and tolerance to flooding via a quiescent strategy. Here we show that HaHB11 expression is induced by ABA, NaCl and water deficit in sunflower seedlings and leaves. Arabidopsis transgenic plants expressing HaHB11, controlled either by its own promoter or by the constitutive 35S CaMV, presented rolled leaves and longer roots than WT when grown under standard conditions. In addition, these plants showed wider stems and more vascular bundles. To deal with drought, HaHB11 transgenic plants closed their stomata faster and lost less water than controls, triggering an enhanced tolerance to such stress condition and also to salinity stress. Concomitantly, ABA-synthesis and sensing related genes were differentially regulated in HaHB11 transgenic plants. Either under long-term salinity stress or mild drought stress, HaHB11 transgenic plants did not exhibit yield penalties. Moreover, alfalfa transgenic plants were generated which also showed enhanced drought tolerance. Altogether, the results indicated that HaHB11 was able to confer drought and salinity tolerance via a complex mechanism which involves morphological, physiological and molecular changes. Copyright © 2016 Elsevier B.V. All rights reserved.

Transcriptomics analysis of hulless barley during grain development with a focus on starch biosynthesis.

PubMed

Tang, Yawei; Zeng, Xingquan; Wang, Yulin; Bai, Lijun; Xu, Qijun; Wei, Zexiu; Yuan, Hongjun; Nyima, Tashi

2017-01-01

Hulless barley, with its unique nutritional value and potential health benefits, has increasingly attracted attentions in recent years. However, the transcription dynamics during hulless barley grain development is not well understood. In the present study, we investigated the transcriptome changes during barley grain development using Illumina paired-end RNA-sequencing. Two datasets of the developing grain transcriptomes from two barley landraces with the differential seed starch synthesis traits were generated, and comparative transcriptome approach in both genotypes was performed. The results showed that 38 differentially expressed genes (DEGs) were found co-modulated in both genotypes during the barley grain development. Of those, the proteins encoded by most of those DGEs were found, such as alpha-amylase-related proteins, lipid-transfer protein, homeodomain leucine zipper (HD-Zip), NUCLEAR FACTOR-Y, subunit B (NF-YBs), as well as MYB transcription factors. More interestingly, two genes Hvulgare_GLEAN_10012370 and Hvulgare_GLEAN_10021199 encoding SuSy, AGPase (Hvulgare_GLEAN_10033640 and Hvulgare_GLEAN_10056301), as well as SBE2b (Hvulgare_GLEAN_10018352) were found to significantly contribute to the regulatory mechanism during grain development in both genotypes. Moreover, six co-expression modules associated with specific biological processes or pathways (M1 to M6) were identified by consensus co-expression network. Significantly enriched pathways of those module genes showed difference in both genotypes. These results will expand our understanding of the complex molecular mechanism of starch synthesis during barley grain development.

Bias with respect to socioeconomic status: A closer look at zip code matching in a pneumococcal vaccine effectiveness study.

PubMed

Link-Gelles, Ruth; Westreich, Daniel; Aiello, Allison E; Shang, Nong; Weber, David J; Holtzman, Corinne; Scherzinger, Karen; Reingold, Arthur; Schaffner, William; Harrison, Lee H; Rosen, Jennifer B; Petit, Susan; Farley, Monica; Thomas, Ann; Eason, Jeffrey; Wigen, Christine; Barnes, Meghan; Thomas, Ola; Zansky, Shelley; Beall, Bernard; Whitney, Cynthia G; Moore, Matthew R

2016-12-01

In 2010, 13-valent pneumococcal conjugate vaccine (PCV13) was introduced in the US for prevention of invasive pneumococcal disease in children. Individual-level socioeconomic status (SES) is a potential confounder of the estimated effectiveness of PCV13 and is often controlled for in observational studies using zip code as a proxy. We assessed the utility of zip code matching for control of SES in a post-licensure evaluation of the effectiveness of PCV13 (calculated as [1-matched odds ratio]*100). We used a directed acyclic graph to identify subsets of confounders and collected SES variables from birth certificates, geo-coding, a parent interview, and follow-up with medical providers. Cases tended to be more affluent than eligible controls (for example, 48.3% of cases had private insurance vs. 44.6% of eligible controls), but less affluent than enrolled controls (52.9% of whom had private insurance). Control of confounding subsets, however, did not result in a meaningful change in estimated vaccine effectiveness (original estimate: 85.1%, 95% CI 74.8-91.9%; adjusted estimate: 82.5%, 95% CI 65.6-91.1%). In the context of a post-licensure vaccine effectiveness study, zip code appears to be an adequate, though not perfect, proxy for individual SES.

Light variations of the population II F-type supergiant HD 46703

NASA Technical Reports Server (NTRS)

Bond, H. E.; Carney, B. W.; Grauer, A. D.

1984-01-01

Photometric monitoring has revealed brightness variations of 0.1 m on a time scale of weeks for HD 46703, a metal-deficient F-type field analog of the stars lying above the horizontal branch in globular clusters. It is suggested that HD 46703 belongs to the '89 Her' class of luminous F-type variables. Since HD 46703 is unquestionably a halo object, it is almost certainly a low-mass star. It is suggested that it, and probably the other 89 Her variables, are masquerading as supergiants during their final evolution off the asymptotic giant branch.

FUV Spectroscopy Of Outflows And Disks Around The Intermediate Mass Pre-main-sequence Stars HD135344B And HD104237

NASA Astrophysics Data System (ADS)

Brown, Alexander; Herczeg, G.; Brown, J. M.; Walter, F. M.; Ayres, T. R.; DAOof TAU Team

2011-01-01

The intermediate-mass, pre-main-sequence (Herbig Ae/Fe) stars HD135344B (F4) and HD104237 (A8 IV-V) are both still surrounded by almost face-on circumstellar disks. The disk around HD135344B is a ``transitional'' disk with a 25 AU radius cleared inner hole but still with some gas and dust very close to the star. We have obtained FUV spectra of these stars using the HST COS and STIS spectrographs that show that both stars have dramatic high-velocity (terminal velocity = 300-400 km/s) outflows and rich fluorescently-excited molecular hydrogen emission, originating primarily from warm gas in their disks. We present these FUV spectra and outline the outflow and disk properties implied by the observed emission and absorption line profiles. The profiles and widths of the molecular hydrogen lines provide strong constraints on the location of the emitting regions. This work is supported by HST grants for GO projects 11828 and 11616, and Chandra grant GO9-0015X to the University of Colorado.

The massive multiple system HD 64315

NASA Astrophysics Data System (ADS)

Lorenzo, J.; Simón-Díaz, S.; Negueruela, I.; Vilardell, F.; Garcia, M.; Evans, C. J.; Montes, D.

2017-10-01

Context. The O6 Vn star HD 64315 is believed to belong to the star-forming region known as NGC 2467, but previous distance estimates do not support this association. Moreover, it has been identified as a spectroscopic binary, but existing data support contradictory values for its orbital period. Aims: We explore the multiple nature of this star with the aim of determining its distance, and understanding its connection to NGC 2467. Methods: A total of 52 high-resolution spectra have been gathered over a decade. We use their analysis, in combination with the photometric data from All Sky Automated Survey and Hipparcos catalogues, to conclude that HD 64315 is composed of at least two spectroscopic binaries, one of which is an eclipsing binary. We have developed our own program to fit four components to the combined line shapes. Once the four radial velocities were derived, we obtained a model to fit the radial-velocity curves using the Spectroscopic Binary Orbit Program (SBOP). We then implemented the radial velocities of the eclipsing binary and the light curves in the Wilson-Devinney code iteratively to derive stellar parameters for its components. We were also able to analyse the non-eclipsing binary, and to derive minimum masses for its components which dominate the system flux. Results: HD 64315 contains two binary systems, one of which is an eclipsing binary. The two binaries are separated by 0.09 arcsec (or 500 AU) if the most likely distance to the system, 5 kpc, is considered. The presence of fainter companions is not excluded by current observations. The non-eclipsing binary (HD 64315 AaAb) has a period of 2.70962901 ± 0.00000021 d. Its components are hotter than those of the eclipsing binary, and dominate the appearance of the system. The eclipsing binary (HD 64315 BaBb) has a shorter period of 1.0189569 ± 0.0000008 d. We derive masses of 14.6 ± 2.3 M⊙ for both components of the BaBb system. They are almost identical; both stars are overfilling their

Maternal Emotions and Self-Efficacy Beliefs in Relation to Boys and Girls with AD/HD

ERIC Educational Resources Information Center

Maniadaki, Katerina; Sonuga-Barke, Edmund; Kakouros, Efthymios; Karaba, Rania

2005-01-01

This study examined the impact of child gender on mothers' emotional responses to AD/HD, self-efficacy beliefs and perceived severity of AD/HD. Mothers (N = 118) of pre-schoolers were presented with a vignette describing a typical boy or girl with AD/HD and then completed three scales relating to their emotional response to AD/HD behaviour, their…

Phylogenetic analysis reveals conservation and diversification of micro RNA166 genes among diverse plant species.

PubMed

Barik, Suvakanta; SarkarDas, Shabari; Singh, Archita; Gautam, Vibhav; Kumar, Pramod; Majee, Manoj; Sarkar, Ananda K

2014-01-01

Similar to the majority of the microRNAs, mature miR166s are derived from multiple members of MIR166 genes (precursors) and regulate various aspects of plant development by negatively regulating their target genes (Class III HD-ZIP). The evolutionary conservation or functional diversification of miRNA166 family members remains elusive. Here, we show the phylogenetic relationships among MIR166 precursor and mature sequences from three diverse model plant species. Despite strong conservation, some mature miR166 sequences, such as ppt-miR166m, have undergone sequence variation. Critical sequence variation in ppt-miR166m has led to functional diversification, as it targets non-HD-ZIPIII gene transcript (s). MIR166 precursor sequences have diverged in a lineage specific manner, and both precursors and mature osa-miR166i/j are highly conserved. Interestingly, polycistronic MIR166s were present in Physcomitrella and Oryza but not in Arabidopsis. The nature of cis-regulatory motifs on the upstream promoter sequences of MIR166 genes indicates their possible contribution to the functional variation observed among miR166 species. Copyright © 2013 Elsevier Inc. All rights reserved.

The Functions of Metallothionein and ZIP and ZnT Transporters: An Overview and Perspective

PubMed Central

Kimura, Tomoki; Kambe, Taiho

2016-01-01

Around 3000 proteins are thought to bind zinc in vivo, which corresponds to ~10% of the human proteome. Zinc plays a pivotal role as a structural, catalytic, and signaling component that functions in numerous physiological processes. It is more widely used as a structural element in proteins than any other transition metal ion, is a catalytic component of many enzymes, and acts as a cellular signaling mediator. Thus, it is expected that zinc metabolism and homeostasis have sophisticated regulation, and elucidating the underlying molecular basis of this is essential to understanding zinc functions in cellular physiology and pathogenesis. In recent decades, an increasing amount of evidence has uncovered critical roles of a number of proteins in zinc metabolism and homeostasis through influxing, chelating, sequestrating, coordinating, releasing, and effluxing zinc. Metallothioneins (MT) and Zrt- and Irt-like proteins (ZIP) and Zn transporters (ZnT) are the proteins primarily involved in these processes, and their malfunction has been implicated in a number of inherited diseases such as acrodermatitis enteropathica. The present review updates our current understanding of the biological functions of MTs and ZIP and ZnT transporters from several new perspectives. PMID:26959009

Huntington's disease (HD): the neuropathology of a multisystem neurodegenerative disorder of the human brain.

PubMed

Rüb, U; Seidel, K; Heinsen, H; Vonsattel, J P; den Dunnen, W F; Korf, H W

2016-11-01

Huntington's disease (HD) is an autosomal dominantly inherited, and currently untreatable, neuropsychiatric disorder. This progressive and ultimately fatal disease is named after the American physician George Huntington and according to the underlying molecular biological mechanisms is assigned to the human polyglutamine or CAG-repeat diseases. In the present article we give an overview of the currently known neurodegenerative hallmarks of the brains of HD patients. Subsequent to recent pathoanatomical studies the prevailing reductionistic concept of HD as a human neurodegenerative disease, which is primarily and more or less exclusively confined to the striatum (ie, caudate nucleus and putamen) has been abandoned. Many recent studies have improved our neuropathological knowledge of HD; many of the early groundbreaking findings of neuropathological HD research have been rediscovered and confirmed. The results of this investigation have led to the stepwise revision of the simplified pathoanatomical and pathophysiological HD concept and culminated in the implementation of the current concept of HD as a multisystem degenerative disease of the human brain. The multisystem character of the neuropathology of HD is emphasized by a brain distribution pattern of neurodegeneration (i) which apart from the striatum includes the cerebral neo-and allocortex, thalamus, pallidum, brainstem and cerebellum, and which (ii) therefore, shares more similarities with polyglutamine spinocerebellar ataxias than previously thought. © 2016 International Society of Neuropathology.

Insights into the pathogenesis of GvHD: what mice can teach us about man.

PubMed

Hülsdünker, J; Zeiser, R

2015-01-01

Acute graft-vs-host disease (GvHD) is a life-threatening complication of allogeneic hematopoietic cell transplantation (allo-HCT). Most of the knowledge about the biology of GvHD is derived from mouse models of this disease and therefore a critical analysis of potential advantages and disadvantages of the murine GvHD models is important to classify and understand the findings made in these models. The central events leading up to GvHD were characterized in three phases which includes the tissue damage-phase, the T cell priming-phase and the effector-phase, when the disease becomes clinically overt. The role of individual cytokines, chemokines, transcription factor or receptors was studied in these models by using gene deficient or transgenic mice in the donor or recipient compartments. Besides, numerous studies have been performed in these models to prevent or treat GvHD. Several recent clinical trials were all based on previously reported findings from the mouse model of GvHD such as the trials on CCR5-blockade, donor statin treatment, vorinostat treatment or adoptive transfer of regulatory T cells for GvHD prevention. The different mouse models for GvHD and graft-vs-leukemia effects are critically reviewed and their impact on current clinical practice is discussed. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Milli-arcsecond images of the Herbig Ae star HD 163296

NASA Astrophysics Data System (ADS)

Renard, S.; Malbet, F.; Benisty, M.; Thiébaut, E.; Berger, J.-P.

2010-09-01

Context. The very close environments of young stars are the hosts of fundamental physical processes, such as planet formation, star-disk interactions, mass accretion, and ejection. The complex morphological structure of these environments has been confirmed by the now quite rich data sets obtained for a few objects by near-infrared long-baseline interferometry. Aims: We gathered numerous interferometric measurements for the young star HD 163296 with various interferometers (VLTI, IOTA, KeckI and CHARA), allowing for the first time an image independent of any a priori model to be reconstructed. Methods: Using the Multi-aperture image Reconstruction Algorithm (MiRA), we reconstruct images of HD 163296 in the H and K bands. We compare these images with reconstructed images obtained from simulated data using a physical model of the environment of HD 163296. Results: We obtain model-independent H and K-band images of the surroundings of HD 163296. The images detect several significant features that we can relate to an inclined asymmetric flared disk around HD 163296 with the strongest intensity at about 4-5 mas. Because of the incomplete spatial frequency coverage, we cannot state whether each of them individually is peculiar in any way. Conclusions: For the first time, milli-arcsecond images of the environment of a young star are produced. These images confirm that the morphology of the close environment of young stars is more complex than the simple models used in the literature so far.

Psychological heterogeneity in AD/HD--a dual pathway model of behaviour and cognition.

PubMed

Sonuga-Barke, Edmund J S

2002-03-10

Psychological accounts have characterised attention-deficit/hyperactivity disorder (AD/HD) as either a neuro-cognitive disorder of regulation or a motivational style. Poor inhibitory control is thought to underpin AD/HD children's dysregulation while delay aversion is a dominant characteristic of their motivational style. A recent 'head to head' study of these two accounts suggest that delay aversion and poor inhibitory control are independent co-existing characteristics of AD/HD (combined type). In the present paper we build on these findings to propose a dual pathway model of AD/HD that recognises two quite distinct sub-types of the disorder. In one AD/HD is the result of the dysregulation of action and thought resulting from poor inhibitory control associated with the meso-cortical branch of the dopamine system projecting in the cortical control centres (e.g. pre-frontal cortex). In the other AD/HD is a motivational style characterised by an altered delay of reward gradient linked to the meso-limbic dopamine branch associated with the reward circuits (e.g. nucleus accumbens). The two pathways are further distinguished at the levels of symptoms, cognitive and motivation profiles and genetic and non-genetic origins.

K-bZIP Mediated SUMO-2/3 Specific Modification on the KSHV Genome Negatively Regulates Lytic Gene Expression and Viral Reactivation

PubMed Central

Yang, Wan-Shan; Hsu, Hung-Wei; Campbell, Mel; Cheng, Chia-Yang; Chang, Pei-Ching

2015-01-01

SUMOylation is associated with epigenetic regulation of chromatin structure and transcription. Epigenetic modifications of herpesviral genomes accompany the transcriptional switch of latent and lytic genes during the virus life cycle. Here, we report a genome-wide comparison of SUMO paralog modification on the KSHV genome. Using chromatin immunoprecipitation in conjunction with high-throughput sequencing, our study revealed highly distinct landscape changes of SUMO paralog genomic modifications associated with KSHV reactivation. A rapid and widespread deposition of SUMO-2/3, compared with SUMO-1, modification across the KSHV genome upon reactivation was observed. Interestingly, SUMO-2/3 enrichment was inversely correlated with H3K9me3 mark after reactivation, indicating that SUMO-2/3 may be responsible for regulating the expression of viral genes located in low heterochromatin regions during viral reactivation. RNA-sequencing analysis showed that the SUMO-2/3 enrichment pattern positively correlated with KSHV gene expression profiles. Activation of KSHV lytic genes located in regions with high SUMO-2/3 enrichment was enhanced by SUMO-2/3 knockdown. These findings suggest that SUMO-2/3 viral chromatin modification contributes to the diminution of viral gene expression during reactivation. Our previous study identified a SUMO-2/3-specific viral E3 ligase, K-bZIP, suggesting a potential role of this enzyme in regulating SUMO-2/3 enrichment and viral gene repression. Consistent with this prediction, higher K-bZIP binding on SUMO-2/3 enrichment region during reactivation was observed. Moreover, a K-bZIP SUMO E3 ligase dead mutant, K-bZIP-L75A, in the viral context, showed no SUMO-2/3 enrichment on viral chromatin and higher expression of viral genes located in SUMO-2/3 enriched regions during reactivation. Importantly, virus production significantly increased in both SUMO-2/3 knockdown and KSHV K-bZIP-L75A mutant cells. These results indicate that SUMO-2/3 modification

No hydrogen exosphere detected around the super-Earth HD 97658 b

NASA Astrophysics Data System (ADS)

Bourrier, V.; Ehrenreich, D.; King, G.; Lecavelier des Etangs, A.; Wheatley, P. J.; Vidal-Madjar, A.; Pepe, F.; Udry, S.

2017-01-01

The exoplanet HD 97658 b provides a rare opportunity to probe the atmospheric composition and evolution of moderately irradiated super-Earths. It transits a bright K star at a moderate orbital distance of 0.08 au. Its low density is compatible with a massive steam envelope that could photodissociate at high altitudes and become observable as escaping neutral hydrogen. Our analysis of three transits with HST/STIS at Lyman-α reveals no such signature, suggesting that the thermosphere of HD 97658 b is not hydrodynamically expanding and is subjected to a low escape of neutral hydrogen (<108 g s-1 at 3σ). Using HST/STIS Lyman-α observations and Chandra/ACIS-S and XMM-Newton/EPIC X-ray observations at different epochs, we find that HD 97658 is in fact a weak and soft X-ray source with signs of chromospheric variability in the Lyman-α line core. We determine an average reference for the intrinsic Lyman-α line and X-EUV (XUV) spectrum of the star, and show that HD 97658 b is in mild conditions of irradiation compared to other known evaporating exoplanets with an XUV irradiation about three times lower than the evaporating warm Neptune GJ436 b. This could be the reason why the thermosphere of HD 97658 b is not expanding: the low XUV irradiation prevents an efficient photodissociation of any putative steam envelope. Alternatively, it could be linked to a low hydrogen content or inefficient conversion of the stellar energy input. The HD 97658 system provides clues for understanding the stability of low-mass planet atmospheres in terms of composition, planetary density, and irradiation. Our study of HD 97658 b can be seen as a control experiment of our methodology, confirming that it does not bias detections of atmospheric escape and underlining its strength and reliability. Our results show that stellar activity can be efficiently discriminated from absorption signatures by a transiting exospheric cloud. They also highlight the potential of observing the upper atmosphere

Evidence That the Directly Imaged Planet HD 131399 Ab Is a Background Star

NASA Astrophysics Data System (ADS)

Nielsen, Eric L.; De Rosa, Robert J.; Rameau, Julien; Wang, Jason J.; Esposito, Thomas M.; Millar-Blanchaer, Maxwell A.; Marois, Christian; Vigan, Arthur; Ammons, S. Mark; Artigau, Etienne; Bailey, Vanessa P.; Blunt, Sarah; Bulger, Joanna; Chilcote, Jeffrey; Cotten, Tara; Doyon, René; Duchêne, Gaspard; Fabrycky, Daniel; Fitzgerald, Michael P.; Follette, Katherine B.; Gerard, Benjamin L.; Goodsell, Stephen J.; Graham, James R.; Greenbaum, Alexandra Z.; Hibon, Pascale; Hinkley, Sasha; Hung, Li-Wei; Ingraham, Patrick; Jensen-Clem, Rebecca; Kalas, Paul; Konopacky, Quinn; Larkin, James E.; Macintosh, Bruce; Maire, Jérôme; Marchis, Franck; Metchev, Stanimir; Morzinski, Katie M.; Murray-Clay, Ruth A.; Oppenheimer, Rebecca; Palmer, David; Patience, Jennifer; Perrin, Marshall; Poyneer, Lisa; Pueyo, Laurent; Rafikov, Roman R.; Rajan, Abhijith; Rantakyrö, Fredrik T.; Ruffio, Jean-Baptiste; Savransky, Dmitry; Schneider, Adam C.; Sivaramakrishnan, Anand; Song, Inseok; Soummer, Remi; Thomas, Sandrine; Wallace, J. Kent; Ward-Duong, Kimberly; Wiktorowicz, Sloane; Wolff, Schuyler

2017-12-01

We present evidence that the recently discovered, directly imaged planet HD 131399 Ab is a background star with nonzero proper motion. From new JHK1L‧ photometry and spectroscopy obtained with the Gemini Planet Imager, VLT/SPHERE, and Keck/NIRC2, and a reanalysis of the discovery data obtained with VLT/SPHERE, we derive colors, spectra, and astrometry for HD 131399 Ab. The broader wavelength coverage and higher data quality allow us to reinvestigate its status. Its near-infrared spectral energy distribution excludes spectral types later than L0 and is consistent with a K or M dwarf, which are the most likely candidates for a background object in this direction at the apparent magnitude observed. If it were a physically associated object, the projected velocity of HD 131399 Ab would exceed escape velocity given the mass and distance to HD 131399 A. We show that HD 131399 Ab is also not following the expected track for a stationary background star at infinite distance. Solving for the proper motion and parallax required to explain the relative motion of HD 131399 Ab, we find a proper motion of 12.3 mas yr-1. When compared to predicted background objects drawn from a galactic model, we find this proper motion to be high but consistent with the top 4% fastest-moving background stars. From our analysis, we conclude that HD 131399 Ab is a background K or M dwarf.

[Relationship between characteristic behaviors of children with AD/HD and mothers' parenting styles].

PubMed

Mano, Shoko; Uno, Hiroyuki

2007-01-01

Previous studies have revealed that mothers of children with attention-deficit/hyperactivity disorder (AD/HD) have an authoritarian parenting style. However, the psychological process of developing an authoritarian parenting style has yet to be clearly defined. To clarify this psychological process, the present study examined the hypothesis that the characteristic behaviors of children with AD/HD initially increase the mothers' parenting stress, which influences their parenting style. Thirty-six mothers of children with AD/HD (children's mean age: 8.1 years) and the same number of controls (children's mean age: 8.4 years) participated in the present study. The mothers' parenting stress was assessed using the Japanese Parenting Stress Index. Parenting styles were assessed using the TK-style scale for evaluating the relationships between parents and children. The results indicated that the mothers of children with AD/HD had significantly higher scores than controls for all parenting stress items and negative parenting style variables (dissatisfaction, reproach, strictness, interference, inconsistency and disagreement of 10 attitudes). Stepwise multiple regression analysis revealed that the characteristic behaviors of children with AD/HD were associated with the degree of attachment in mothers, which was related to the strict and reproachful parenting style in the AD/HD group. These results suggest that mothers of children with AD/HD are likely to have a strict and reproachful parenting style as a result of a lack of attachment with the child.

The membrane tethered transcription factor EcbZIP17 from finger millet promotes plant growth and enhances tolerance to abiotic stresses.

PubMed

Ramakrishna, Chopperla; Singh, Sonam; Raghavendrarao, Sangala; Padaria, Jasdeep C; Mohanty, Sasmita; Sharma, Tilak Raj; Solanke, Amolkumar U

2018-02-01

The occurrence of various stresses, as the outcome of global climate change, results in the yield losses of crop plants. Prospecting of genes in stress tolerant plant species may help to protect and improve their agronomic performance. Finger millet (Eleusine coracana L.) is a valuable source of superior genes and alleles for stress tolerance. In this study, we isolated a novel endoplasmic reticulum (ER) membrane tethered bZIP transcription factor from finger millet, EcbZIP17. Transgenic tobacco plants overexpressing this gene showed better vegetative growth and seed yield compared with wild type (WT) plants under optimal growth conditions and confirmed upregulation of brassinosteroid signalling genes. Under various abiotic stresses, such as 250 mM NaCl, 10% PEG6000, 400 mM mannitol, water withdrawal, and heat stress, the transgenic plants showed higher germination rate, biomass, primary and secondary root formation, and recovery rate, compared with WT plants. The transgenic plants exposed to an ER stress inducer resulted in greater leaf diameter and plant height as well as higher expression of the ER stress-responsive genes BiP, PDIL, and CRT1. Overall, our results indicated that EcbZIP17 improves plant growth at optimal conditions through brassinosteroid signalling and provide tolerance to various environmental stresses via ER signalling pathways.

Wind Variability of B Supergiants. No. 1; The Rapid Rotator HD 64760 (B0.5 Ib)

NASA Technical Reports Server (NTRS)

Massa, Derck; Prinja, Raman K.; Fullerton, Alexander W.

1995-01-01

We present the results of a 6 day time series of observations of the rapidly rotating B0.5 Ib star HD 64760. We point out several reasons why such intermediate luminosity B supergiants are ideal targets for wind variability studies and then present our results that show the following: continuous wind activity throughout the 6 day run with the wind never in steady state for more than a few hr; wind variability very near nu = 0 km sec(exp -1) in the resonance lines from the lower ionization stages (Al III and C II); a distinct correlation between variability in the Si III ; lambda(lambda)1300 triplets, the strong C III (lambda)1247 singlet, and the onset of extremely strong wind activity, suggesting a connection between photospheric and wind activity; long temporal coherence in the behavior of the strong absorption events; evidence for large-scale spatial coherence, implied by a whole scale, simultaneous weakening in the wind absorption over a wide range in velocities; and ionization variability in the wind accompanying the largest changes in the absorption strengths of the wind lines. In addition, modeling of the wind lines provides the following information about the state the wind in HD 64760. The number of structures on the portion of a constant velocity surface occulting the stellar disk at a particular time must be quite small, while the number on the entire constant velocity surface throughout the wind must be large. The escape probability at low velocity is overestimated by a normal beta approx. 1 velocity law, perhaps due to the presence of low-velocity shocks deep in the wind or a shallow velocity gradient at low velocity. Estimates of the ionization structure in the wind indicate that the ionization ratios are not those expected from thermal equilibrium wind models or from an extrapolation of previous O star results. The large observed q(N V)/q(Si IV) ratio is almost certainly due to distributed X-rays, but the level of ionization predicted by distributed

An 80 au cavity in the disk around HD 34282

NASA Astrophysics Data System (ADS)

van der Plas, G.; Ménard, F.; Canovas, H.; Avenhaus, H.; Casassus, S.; Pinte, C.; Caceres, C.; Cieza, L.

2017-11-01

Context. Large cavities in disks are important testing grounds for the mechanisms proposed to drive disk evolution and dispersion, such as dynamical clearing by planets and photoevaporation. Aims: We aim to resolve the large cavity in the disk around HD 34282, whose presence has been predicted by previous studies modeling the spectral energy distribution of the disk. Methods: Using ALMA band 7 observations we studied HD 34282 with a spatial resolution of 0.10″ × 0.17'' at 345 GHz. Results: We resolve the disk around HD 34282 into a ring between 0.24'' and 1.15'' (78 and 374 au adopting a distance of 325 pc). The emission in this ring shows azimuthal asymmetry centered at a radial distance of 0.46'' and a position angle of 135° and an azimuthal FWHM of 51°. We detect CO emission both inside the disk cavity and as far out as 2.7 times the radial extent of the dust emission. Conclusions: Both the large disk cavity and the azimuthal structure in the disk around HD 34282 can be explained by the presence of a 50 Mjup brown dwarf companion at a separation of ≈0.1''.

The Death Spiral of the Hot Jupiter Exoplanet HD 189733b

NASA Astrophysics Data System (ADS)

Dowling Jones, Liam; Marchioni, Lucas; Guinan, Edward; Engle, Scott

2018-01-01

HD 189733 is a quintessential example of hot Jupiter-type exoplanet systems in which a gas giant planet with a mass similar to Jupiter is orbiting extremely close to its host star. HD 189733 is the nearest and brightest hot Jupiter system discovered so far and undergoes transit eclipses. Because of this, HD 189733 is well studied across the electromagnetic spectrum. It consists of a 7.7 mag K1.5 V host star and a Jupiter-size planet orbiting with a period of P =2.22 days, only located only 0.030 AU from its host star.About ten years ago HD 189733 system was discovered to be accompanied by gravitationally-bound red dwarf M4 V star companion (HD 189733 B). It was found previously by Guinan et al. (2017) that the age measurement (~0.7 Gyr) of the K-type star indicated by its 11.95 day rotation period and corresponding moderately high levels of coronal X-ray and chromospheric emissions do not agree with the much older age of ~6 - 9 Gyr indicated from the low X-ray activity of the dM companion star. This age discrepancy is can be resolved by assuming an increase in angular momentum or “spin-up” of the HD 189733A by its hosted planet. It is probable is that this extra angular momentum was acquired from the orbiting exoplanet from the tidal and magnetic interactions of the planet and host star.Photometric observations of the planetary transit eclipses of HD 189733b have been carried out for over 11 years. Using new transit timings that we have obtained with the 1.3-m Robotically Controlled Telescope (RCT) when combined with numerous timings available in the literature, we have discovered a very small decrease in the orbital period of the HD 189733b. The change in period is dP/dt = 0.87 sec/100 yrs. This finding support the transfer of orbital angular momentum of the planet to the host star - thus spinning-up the host star and shrinking the orbit of the planet. At this rate of period decrease, the planet will be tidally disrupted in less than 40 million years. However

Arrest of trans-SNARE zippering uncovers loosely and tightly docked intermediates in membrane fusion.

PubMed

Yavuz, Halenur; Kattan, Iman; Hernandez, Javier Matias; Hofnagel, Oliver; Witkowska, Agata; Raunser, Stefan; Walla, Peter Jomo; Jahn, Reinhard

2018-04-17

Soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins mediate intracellular membrane fusion in the secretory pathway. They contain conserved regions, termed SNARE motifs, that assemble between opposing membranes directionally from their N-termini to their membrane-proximal C-termini in a highly exergonic reaction. However, how this energy is utilized to overcome the energy barriers along the fusion pathway is still under debate. Here we have used mutants of the SNARE synaptobrevin to arrest trans-SNARE zippering at defined stages. We have uncovered two distinct vesicle docking intermediates, where the membranes are loosely and tightly connected, respectively. The tightly connected state is irreversible and independent of maintaining assembled SNARE complexes. Together, our results shed new light on the intermediate stages along the pathway of membrane fusion. Published under license by The American Society for Biochemistry and Molecular Biology, Inc.

Variability of Disk Emission in Pre-Main Sequence and Related Stars. I. HD 31648 and HD 163296 - Isolated Herbig Ae Stars Driving Herbig-Haro Flows

NASA Technical Reports Server (NTRS)

Sitko, Michael L.; Carpenter, William J.; Kimes, Robin L.; Lynch, David K.; Russell, Ray W.; Rudy, Richard J.; Mazuk, Stephan M.; Venturini, Catherine C.; Puetter, Richard C.; Grady, Carol A.;

Contact-dependent killing by Caulobacter crescentus via cell surface-associated, glycine zipper proteins.

PubMed

García-Bayona, Leonor; Guo, Monica S; Laub, Michael T

2017-03-21

Most bacteria are in fierce competition with other species for limited nutrients. Some bacteria can kill nearby cells by secreting bacteriocins, a diverse group of proteinaceous antimicrobials. However, bacteriocins are typically freely diffusible, and so of little value to planktonic cells in aqueous environments. Here, we identify an atypical two-protein bacteriocin in the α-proteobacterium Caulobacter crescentus that is retained on the surface of producer cells where it mediates cell contact-dependent killing. The bacteriocin-like proteins CdzC and CdzD harbor glycine-zipper motifs, often found in amyloids, and CdzC forms large, insoluble aggregates on the surface of producer cells. These aggregates can drive contact-dependent killing of other organisms, or Caulobacter cells not producing the CdzI immunity protein. The Cdz system uses a type I secretion system and is unrelated to previously described contact-dependent inhibition systems. However, Cdz-like systems are found in many bacteria, suggesting that this form of contact-dependent inhibition is common.

Trp zipper folding kinetics by molecular dynamics and temperature-jump spectroscopy

NASA Astrophysics Data System (ADS)

Snow, Christopher D.; Qiu, Linlin; Du, Deguo; Gai, Feng; Hagen, Stephen J.; Pande, Vijay S.

2004-03-01

We studied the microsecond folding dynamics of three hairpins (Trp zippers 1-3, TZ1-TZ3) by using temperature-jump fluorescence and atomistic molecular dynamics in implicit solvent. In addition, we studied TZ2 by using time-resolved IR spectroscopy. By using distributed computing, we obtained an aggregate simulation time of 22 ms. The simulations included 150, 212, and 48 folding events at room temperature for TZ1, TZ2, and TZ3, respectively. The all-atom optimized potentials for liquid simulations (OPLSaa) potential set predicted TZ1 and TZ2 properties well; the estimated folding rates agreed with the experimentally determined folding rates and native conformations were the global potential-energy minimum. The simulations also predicted reasonable unfolding activation enthalpies. This work, directly comparing large simulated folding ensembles with multiple spectroscopic probes, revealed both the surprising predictive ability of current models as well as their shortcomings. Specifically, for TZ1-TZ3, OPLS for united atom models had a nonnative free-energy minimum, and the folding rate for OPLSaa TZ3 was sensitive to the initial conformation. Finally, we characterized the transition state; all TZs fold by means of similar, native-like transition-state conformations.

Spectroscopic characterization of HD 95086 b with the Gemini Planet Imager

DOE PAGES

De Rosa, Robert J.; Rameau, Julien; Patience, Jenny; ...

2016-06-21

Here, we present new H (1.5–1.8 μm) photometric and K 1 (1.9–2.2 μm) spectroscopic observations of the young exoplanet HD 95086 b obtained with the Gemini Planet Imager. The H-band magnitude has been significantly improved relative to previous measurements, whereas the low-resolution K 1 (more » $$\\lambda /\\delta \\lambda \\approx 66$$) spectrum is featureless within the measurement uncertainties and presents a monotonically increasing pseudo-continuum consistent with a cloudy atmosphere. By combining these new measurements with literature $$L^{\\prime} $$ photometry, we compare the spectral energy distribution (SED) of the planet to other young planetary-mass companions, field brown dwarfs, and to the predictions of grids of model atmospheres. HD 95086 b is over a magnitude redder in $${K}_{1}-L^{\\prime} $$ color than 2MASS J12073346–3932539 b and HR 8799 c and d, despite having a similar $$L^{\\prime} $$ magnitude. Considering only the near-infrared measurements, HD 95086 b is most analogous to the brown dwarfs 2MASS J2244316+204343 and 2MASS J21481633+4003594, both of which are thought to have dusty atmospheres. Morphologically, the SED of HD 95086 b is best fit by low temperature ($${T}_{{\\rm{eff}}}$$ = 800–1300 K), low surface gravity spectra from models which simulate high photospheric dust content. This range of effective temperatures is consistent with field L/T transition objects, but the spectral type of HD 95086 b is poorly constrained between early L and late T due to its unusual position the color–magnitude diagram, demonstrating the difficulty in spectral typing young, low surface gravity substellar objects. As one of the reddest such objects, HD 95086 b represents an important empirical benchmark against which our current understanding of the atmospheric properties of young extrasolar planets can be tested.« less

MULTIWAVELENGTH OBSERVATIONS OF THE RUNAWAY BINARY HD 15137

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

McSwain, M. Virginia; Aragona, Christina; Marsh, Amber N.

2010-03-15

HD 15137 is an intriguing runaway O-type binary system that offers a rare opportunity to explore the mechanism by which it was ejected from the open cluster of its birth. Here, we present recent blue optical spectra of HD 15137 and derive a new orbital solution for the spectroscopic binary and physical parameters of the O star primary. We also present the first XMM-Newton observations of the system. Fits of the EPIC spectra indicate soft, thermal X-ray emission consistent with an isolated O star. Upper limits on the undetected hard X-ray emission place limits on the emission from a proposedmore » compact companion in the system, and we rule out a quiescent neutron star (NS) in the propeller regime or a weakly accreting NS. An unevolved secondary companion is also not detected in our optical spectra of the binary, and it is difficult to conclude that a gravitational interaction could have ejected this runaway binary with a low mass optical star. HD 15137 may contain an elusive NS in the ejector regime or a quiescent black hole with conditions unfavorable for accretion at the time of our observations.« less

Remarkable long-term changes in the small Magellanic Cloud Wolf-Rayet system HD 5980

NASA Technical Reports Server (NTRS)

Koenigsberger, G.; Moffat, A. F. J.; St-Louis, N.; Auer, L. H.; Drissen, L.; Seggewiss, W.

1994-01-01

In this paper we report the remarkable changes which occured in the Small Magellanic Cloud W-R system HD5980 = AB5 between 1978 and 1991. Within this timescale, there has been a systematic enhancement (by factors of 2-10 depending on the line) in the equivalent widths of all emission lines, and a change in the relative strengths of N III, N IV, and N V lines. Currently, the W-R spectrum is more typical of a WN6 star than a WN3 or WN4, as it was originally classified. The terminal speed of the wind has diminished by approximately 600 km/s, while the system has brightened in the visual by 0.45 mag. The UV (1850 A) continuum changed by less than 0.13 mag. The change from WN3 or WN4 to WN6 is unprecedented. The system appears to be composed at least three stars: two WNs in mutual 19.266 day orbit and an O-type supergiant. We propose that the changes observed in HD 5980 are related to an increase in wind density of one (or both?) of the W-R components, where the brighter WN6 component will dominate the W-R spectrum after the change, and we speculate that this modification of the wind structure is driven by tidal interaction induced by a possible current periastron passage of the third component in the system.

Characterization of Runella slithyformis HD-Pnk, a bifunctional DNA/RNA end-healing enzyme composed of an N-terminal 2',3' -phosphoesterase HD domain and a C-terminal 5' -OH polynucleotide kinase domain.

PubMed

Munir, Annum; Shuman, Stewart

2016-11-28

5' and 3' end healing are key steps in nucleic acid break repair in which 5' -OH ends are phosphorylated by a polynucleotide kinase and 3' -PO 4 or 2',3' -cyclic-PO 4 ends are hydrolyzed by a phosphoesterase to generate the 5' -PO 4 and 3' -OH termini required for sealing by classic polynucleotide ligases. End healing and sealing enzymes are present in diverse bacterial taxa, often organized as modular units within a single multifunctional polypeptide or as subunits of a repair complex. Here we identify and characterize Runella slithyformis HD-Pnk as a novel bifunctional end-healing enzyme composed of an N-terminal 2',3' -phosphoesterase HD domain and a C-terminal 5' -OH polynucleotide kinase P-loop domain. HD-Pnk phosphorylates 5' -OH polynucleotides (9-mers or longer) in the presence of magnesium and any NTP donor. HD-Pnk dephosphorylates RNA 2',3' -cyclic phosphate, RNA 3' -phosphate, RNA 2' -phosphate, and DNA 3' -phosphate ends in the presence of a transition metal cofactor, which can be nickel, copper or cobalt. HD-Pnkp homologs are present in genera from eleven bacterial phyla and are often encoded in an operon with a putative ATP-dependent polynucleotide ligase. The present study provides insights to the diversity of nucleic acid repair strategies via the characterization of Runella slithyformis HD-Pnkp as the exemplar of a novel clade of dual 5' and 3' end-healing enzymes that phosphorylate 5' -OH termini and dephosphorylate 2',3' -cyclic-PO 4 , 3' -PO 4 , and 2' -PO 4 ends. The distinctive feature of HD-Pnk is its domain composition: a fusion of an N-terminal HD phosphohydrolase module to a C-terminal P-loop polynucleotide kinase module. Homologs of Runella HD-Pnk with the same domain composition, domain order, and similar polypeptide size are distributed widely among genera from eleven bacterial phyla. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

The violent interstellar environment around the Wolf-Rayet star HD 192163

NASA Technical Reports Server (NTRS)

Nichols-Bohlin, Joy; Fesen, Robert A.

1993-01-01

IRAS Skyflux IR images, high-dispersion IUE UV spectra, optical spectra, and optical interference filter images are used to investigate the nature of the interstellar environment around the Wolf-Rayet star HD 192163. IRAS images show an apparent 1.5 x 1.8 deg IR emission shell very nearly centered on HD 192163, which is designated G75.5+2.4. It is suggested that this shell is a possible unrecognized SNR with an estimated age of not less than 100,000 yr if at the assumed 1.8-kpc distance of HD 192163. A well-defined 2 x 4.5 deg region of weak IR emission lying to the southeast of HD 192163 appears to be the IR signature of the Cyg OB1 superbubble. Analysis of IUE spectra shows that high-velocity components of UV interstellar absorption lines are present for both high and low ionization lines in 18 of 22 stars located in the Cyg OB1/OB3 direction with a velocity range of +/- 90 km/s. A possible evolutionary history for this region is outlined.

AtHD2D Gene Plays a Role in Plant Growth, Development, and Response to Abiotic Stresses in Arabidopsis thaliana.

PubMed

Han, Zhaofen; Yu, Huimin; Zhao, Zhong; Hunter, David; Luo, Xinjuan; Duan, Jun; Tian, Lining

2016-01-01

The histone deacetylases play important roles in the regulation of gene expression and the subsequent control of a number of important biological processes, including those involved in the response to environmental stress. A specific group of histone deacetylase genes, HD2, is present in plants. In Arabidopsis, HD2s include HD2A, HD2B, HD2C, and HD2D. Previous research showed that HD2A, HD2B, and HD2C are more related in terms of expression and function, but not HD2D. In this report, we studied different aspects of AtHD2D in Arabidopsis with respect to plant response to drought and other abiotic stresses. Bioinformatics analysis indicates that HD2D is distantly related to other HD2 genes. Transient expression in Nicotiana benthamiana and stable expression in Arabidopsis of AtHD2D fused with gfp showed that AtHD2D was expressed in the nucleus. Overexpression of AtHD2D resulted in developmental changes including fewer main roots, more lateral roots, and a higher root:shoot ratio. Seed germination and plant flowering time were delayed in transgenic plants expressing AtHD2D, but these plants exhibited higher degrees of tolerance to abiotic stresses, including drought, salt, and cold stresses. Physiological studies indicated that the malondialdehyde (MDA) content was high in wild-type plants but in plants overexpressing HD2D the MDA level increased slowly in response to stress conditions of drought, cold, and salt stress. Furthermore, electrolyte leakage in leaf cells of wild type plants increased but remained stable in transgenic plants. Our results indicate that AtHD2D is unique among HD2 genes and it plays a role in plant growth and development regulation and these changes can modulate plant stress responses.

Clarifying the Status of HD 100546 as Observed by the Gemini Planet Imager

NASA Astrophysics Data System (ADS)

Currie, Thayne; Brittain, Sean; Grady, Carol A.; Kenyon, Scott J.; Muto, Takayuki

2017-12-01

HD 100546 is a young, early-type star and key laboratory for studying gas giant planet formation. GPI data taken in 2015 and reported by Currie et al. (2015) recover the previously-identified protoplanet candidate HD 100546 b and identify a second emission source at ~13--14 au: either a disk hot spot or a second protoplanetary candidate (HD 100546 "c"). In this short research note, we update the status of HD 100546 as observed by the Gemini Planet Imager by rereducing our original data using a different PSF subtraction method (KLIP instead of A-LOCI), rereducing recently public GPI Campaign Team (GPIES) data, and comparing the quality of the two data sets. Our results support the original findings in Currie et al. (2015).

Major zircon megacryst suites of the Indo-Pacific lithospheric margin (ZIP) and their petrogenetic and regional implications

NASA Astrophysics Data System (ADS)

Sutherland, Lin; Graham, Ian; Yaxley, Gregory; Armstrong, Richard; Giuliani, Gaston; Hoskin, Paul; Nechaev, Victor; Woodhead, Jon

2016-04-01

Zircon megacrysts (± gem corundum) appear in basalt fields of Indo-Pacific origin over a 12,000 km zone (ZIP) along West Pacific continental margins. Age-dating, trace element, oxygen and hafnium isotope studies on representative zircons (East Australia-Asia) indicate diverse magmatic sources. The U-Pb (249 to 1 Ma) and zircon fission track (ZFT) ages (65 to 1 Ma) suggest thermal annealing during later basalt transport, with < 1 to 203 Ma gaps between the U-Pb and ZFT ages. Magmatic growth zonation and Zr/Hf ratios (0.01-0.02) suggest alkaline magmatic sources, while Ti—in—zircon thermometry suggests that most zircons crystallized within ranges between 550 and 830 °C. Chondrite-normalised multi-element plots show variable enrichment patterns, mostly without marked Eu depletion, indicating little plagioclase fractionation in source melts. Key elements and ratios matched against zircons from magmatic rocks suggest a range of ultramafic to felsic source melts. Zircon O-isotope ratios (δ18O in the range 4 to 11‰) and initial Hf isotope ratios (ɛHf in the range +2 to +14) encompass ranges for both mantle and crustal melts. Calculated Depleted Mantle (TDM 0.03-0.56 Ga) and Crustal Residence (0.20-1.02 Ga) model ages suggest several mantle events, continental break-ups (Rodinia and Gondwana) and convergent margin collisions left imprints in the zircon source melts. East Australian ZIP sites reflect prolonged intraplate magmatism (~85 Ma), often during times of fast-migrating lithosphere. In contrast, East Asian-Russian ZIP sites reflect later basaltic magmatism (<40 Ma), often linked to episodes of back-arc rifting and spreading, slow-migrating lithosphere and slab subduction.

The Rhetorical Construction of the AD/HD Subject: Managing the Self

ERIC Educational Resources Information Center

Comstock, Edward

2015-01-01

As the diagnosis of AD/HD becomes more frequent in our schools, and as many individuals across ages embrace an AD/HD identity, scholars need to account for the lived experience of the disorder to understand the meanings individuals give to it. This paper analyses the relationship between ethical practices of self-formation, power, and knowledge…

Direct imaging of an asymmetric debris disk in the HD 106906 planetary system

DOE PAGES

Kalas, Paul G.; Rajan, Abhijith; Wang, Jason J.; ...

2015-11-13

Here, we present the first scattered light detections of the HD 106906 debris disk using the Gemini/Gemini Planet Imager in the infrared and Hubble Space Telescope (HST)/Advanced Camera for Surveys in the optical. HD 106906 is a 13 Myr old F5V star in the Sco–Cen association, with a previously detected planet-mass candidate HD 106906b projected 650 AU from the host star. Our observations reveal a near edge-on debris disk that has a central cleared region with radius ~50 AU, and an outer extent >500 AU. The HST data show that the outer regions are highly asymmetric, resembling the "needle" morphologymore » seen for the HD 15115 debris disk. The planet candidate is oriented ~21° away from the position angle of the primary's debris disk, strongly suggesting non-coplanarity with the system. We hypothesize that HD 106906b could be dynamically involved in the perturbation of the primary's disk, and investigate whether or not there is evidence for a circumplanetary dust disk or cloud that is either primordial or captured from the primary. In conclusion, we show that both the existing optical properties and near-infrared colors of HD 106906b are weakly consistent with this possibility, motivating future work to test for the observational signatures of dust surrounding the planet.« less

Two K Giants with Supermeteoritic Lithium Abundances: HDE 233517 and HD 9746

NASA Astrophysics Data System (ADS)

Balachandran, Suchitra C.; Fekel, Francis C.; Henry, Gregory W.; Uitenbroek, Han

2000-10-01

Two unusual Li-rich K giants, HDE 233517 and HD 9746, have been studied. Optical spectroscopy and photometry have been obtained to determine the fundamental parameters of HDE 233517, a single K2 III with an extremely large infrared excess. The spectra yield Teff=4475 K, logg=2.25, [Fe/H]=-0.37, vsini=17.6 km s-1, and a non-LTE logɛ(7Li)=4.22. Photometric observations reveal low-amplitude light variability with a period of 47.9 days. Combined with other parameters, this results in a minimum radius of 16.7 Rsolar and minimum distance of 617 pc. Comparison of spectra obtained in 1994 and 1996 show profile variations in Hα and the Na D lines indicative of changing mass loss. Optical spectra of HD 9746, a chromospherically active giant, were analyzed. The Teff=4400 K and revised Hipparcos-based gravity of logg=2.30 lead to a non-LTE logɛ(7Li)=3.75. The Li abundances in both stars are supermeteoritic. By the inclusion and exclusion of 6Li in the syntheses, we show that consistent 7Li abundances are obtained only when 6Li is absent in the synthetic fit. This provides evidence for fresh 7Li production and excludes both preservation of primordial Li and planetary accretion as viable scenarios for the formation of Li-rich giants. Both stars lie in close proximity to the red giant luminosity bump supporting the hypothesis that 7Li production is caused by the same mixing mechanism that later results in CN processing and lowers the 12C/13C ratio to nonstandard values.

Variability of Disk Emission in Pre-Main-Sequence and Related Stars. I. HD 31648 and HD 163296: Isolated Herbig Ae Stars Driving Herbig-Haro Flows

NASA Astrophysics Data System (ADS)

Sitko, Michael L.; Carpenter, William J.; Kimes, Robin L.; Wilde, J. Leon; Lynch, David K.; Russell, Ray W.; Rudy, Richard J.; Mazuk, Stephan M.; Venturini, Catherine C.; Puetter, Richard C.; Grady, Carol A.; Polomski, Elisha F.; Wisnewski, John P.; Brafford, Suellen M.; Hammel, H. B.; Perry, R. Brad

2008-05-01

Infrared photometry and spectroscopy covering a time span of a quarter-century are presented for HD 31648 (MWC 480) and HD 163296 (MWC 275). Both are isolated Herbig Ae stars that exhibit signs of active accretion, including driving bipolar flows with embedded Herbig-Haro (HH) objects. HD 163296 was found to be relatively quiescent photometrically in its inner disk region, with the exception of a major increase in emitted flux in a broad wavelength region centered near 3 μm in 2002. In contrast, HD 31648 has exhibited sporadic changes in the entire 3-13 μm region throughout this span of time. In both stars, the changes in the 1-5 μm flux indicate structural changes in the region of the disk near the dust sublimation zone, possibly causing its distance from the star to vary with time. Repeated thermal cycling through this region will result in the preferential survival of large grains, and an increase in the degree of crystallinity. The variability observed in these objects has important consequences for the interpretation of other types of observations. For example, source variability will compromise models based on interferometry measurements unless the interferometry observations are accompanied by nearly simultaneous photometric data.

Chromospherically active stars. III - HD 26337 = EI Eri: An RS CVn candidate for the Doppler-imaging technique

NASA Technical Reports Server (NTRS)

Fekel, Francis C.; Quigley, Robert; Gillies, Kim; Africano, John L.

1987-01-01

Spectroscopic observations of the chromospherically active G5 IV single-lined binary HD 26337 = EI Eri are presented. An orbital period of 1.94722 days is found for the star. It has moderately strong Ca II H and K emission and strong ultraviolet emission features, while H-alpha is a weak absorption feature that is variable in strength. The inclination of the system is 46 + or - 12 deg, and the unseen secondary is probably a late K or early M dwarf. The v sin i of the primary is 50 + or - 3 km/s, resulting in a minimum radius of 1.9 + or - 0.1 solar radius. The star is within the required limits for Doppler imaging. The primary is close to filling its Roche lobe, resulting in a strong constraint that the mass ratio is 2.6 or greater, with a primary mass of at least 1.4 solar mass. The distance to the system is estimated at 75 pc.

Copernicus observations of distant unreddened stars. II - Line of sight to HD 50896

NASA Technical Reports Server (NTRS)

Shull, J. M.

1977-01-01

Copernicus UV data on interstellar lines toward HD 50896, a Wolf-Rayet star, are analyzed to study abundances and physical conditions in the line of sight. About 20% of the low-velocity neutral gas is contained in a dense cloud with 10% to 50% of its hydrogen in molecular form; the atomic abundances show typical interstellar depletions. The low-velocity H II gas may be associated with the high ionizing flux of the Wolf-Rayet star or with H II regions along the line of sight. Si III exhibits strong absorption shortward of the low-velocity H II gas, characteristic of a collisionally ionized component at 30,000 to 80,000 K; the possible connections with an unobserved supernova remnant or stellar mass loss are discussed. High-velocity features at 78 and -96 km/sec, in which Fe and Si are near their cosmic abundances, are also indicative of strong shocks.

Three-dimensional (3D) structure prediction and function analysis of the chitin-binding domain 3 protein HD73_3189 from Bacillus thuringiensis HD73.

PubMed

Zhan, Yiling; Guo, Shuyuan

2015-01-01

Bacillus thuringiensis (Bt) is capable of producing a chitin-binding protein believed to be functionally important to bacteria during the stationary phase of its growth cycle. In this paper, the chitin-binding domain 3 protein HD73_3189 from B. thuringiensis has been analyzed by computer technology. Primary and secondary structural analyses demonstrated that HD73_3189 is negatively charged and contains several α-helices, aperiodical coils and β-strands. Domain and motif analyses revealed that HD73_3189 contains a signal peptide, an N-terminal chitin binding 3 domains, two copies of a fibronectin-like domain 3 and a C-terminal carbohydrate binding domain classified as CBM_5_12. Moreover, analysis predicted the protein's associated localization site to be the cell wall. Ligand site prediction determined that amino acid residues GLU-312, TRP-334, ILE-341 and VAL-382 exposed on the surface of the target protein exhibit polar interactions with the substrate.

HD 172555: Detection of 63 micrometers [OI] Emission in a Debris Disc

NASA Technical Reports Server (NTRS)

Riviere-Marichalar, P.; Barrado, D.; Augereau, J. -C.; Thi, W. F.; Roberge, A.; Eiroa, C.; Montesinos, B.; Meeus, G.; Howard, C.; Sandell, G.;

Functional magnetic resonance imaging of working memory in Huntington's disease: cross-sectional data from the IMAGE-HD study.

PubMed

Georgiou-Karistianis, Nellie; Stout, Julie C; Domínguez D, Juan F; Carron, Sarah P; Ando, Ayaka; Churchyard, Andrew; Chua, Phyllis; Bohanna, India; Dymowski, Alicia R; Poudel, Govinda; Egan, Gary F

2014-05-01

We used functional magnetic resonance imaging (fMRI) to investigate spatial working memory (WM) in an N-BACK task (0, 1, and 2-BACK) in premanifest Huntington's disease (pre-HD, n = 35), early symptomatic Huntington's disease (symp-HD, n = 23), and control (n = 32) individuals. Overall, both WM conditions (1-BACK and 2-BACK) activated a large network of regions throughout the brain, common to all groups. However, voxel-wise and time-course analyses revealed significant functional group differences, despite no significant behavioral performance differences. During 1-BACK, voxel-wise blood-oxygen-level-dependent (BOLD) signal activity was significantly reduced in a number of regions from the WM network (inferior frontal gyrus, anterior insula, caudate, putamen, and cerebellum) in pre-HD and symp-HD groups, compared with controls; however, time-course analysis of the BOLD response in the dorsolateral prefrontal cortex (DLPFC) showed increased activation in symp-HD, compared with pre-HD and controls. The pattern of reduced voxel-wise BOLD activity in pre-HD and symp-HD, relative to controls, became more pervasive during 2-BACK affecting the same structures as in 1-BACK, but also incorporated further WM regions (anterior cingulate gyrus, parietal lobe and thalamus). The DLPFC BOLD time-course for 2-BACK showed a reversed pattern to that observed in 1-BACK, with a significantly diminished signal in symp-HD, relative to pre-HD and controls. Our findings provide support for functional brain reorganisation in cortical and subcortical regions in both pre-HD and symp-HD, which are modulated by task difficulty. Moreover, the lack of a robust striatal BOLD signal in pre-HD may represent a very early signature of change observed up to 15 years prior to clinical diagnosis. Copyright © 2013 Wiley Periodicals, Inc.

AD/HD Symptoms and Conduct Problems: Similarities and Differences in Maternal Perceptions

ERIC Educational Resources Information Center

Maniadaki, Katerina; Sonuga-Barke, Edmund; Kakouros, Efthymios; Karaba, Rania

2006-01-01

Several theories attempt to explain the high co-occurrence of Attention Deficit/ Hyperactivity Disorder (AD/HD) and Conduct Problems (CP). A strong possibility is that AD/HD behaviours lead to the development of CP, due to family coercive interaction patterns, maintained through parental false beliefs regarding child problem behaviour. We compared…

Dayside atmospheric structure of HD209458b from Spitzer eclipses

NASA Astrophysics Data System (ADS)

Reinhard, Matthew; Harrington, Joseph; Challener, Ryan; Cubillos, Patricio; Blecic, Jasmina

2017-10-01

HD209458b is a hot Jupiter with a radius of 1.26 ± 0.08 Jupiter radii (Richardson et al, 2006) and a mass of 0.64 ± 0.09 Jupiter masses (Snellen et al, 2010). The planet orbits a G0 type star with an orbital period of 3.52472 ± 2.81699e-05 days, and a relatively low eccentricity of 0.0082 +0.0078/-0.0082 (Wang and Ford 2013). We report the analysis of observations of HD209458b during eclipse, taken in the 3.6 and 4.5 micron channels by the Spitzer Space Telescope's Infrared Array Camera (Program 90186). We produce a photometric light curve of the eclipses in both channels, using our Photometry for Orbits Eclipses and Transits (POET) code, and calculate the brightness temperatures and eclipse depths. We also present best estimates of the atmospheric parameters of HD209458b using our Bayesian Atmospheric Radiative Transfer (BART) code. These are some preliminary results of what will be an analysis of all available Spitzer data for HD209458b. Spitzer is operated by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. This work was supported by NASA Planetary Atmospheres grant NX12AI69G and NASA Astrophysics Data Analysis Program grant NNX13AF38G.

The composite nature of the peculiar star HR 6560 (HD 159870)

NASA Technical Reports Server (NTRS)

Wegner, Gary; Cowley, Charles R.

1992-01-01

Ground-based high-dispersion photographic spectra and ultraviolet spectra obtained with the IUE satellite are described and employed to determine the nature of the peculiar star HR 6560 (HD 159870). Previously this object had been described as both a composite system and as a strong Fm star. The UBVRI, Stromgren, and ultraviolet colors of HR 6560 are compared with objects classified composite from the Bright Star Catalogue and normal dwarfs and giants. The colors of HR 6560 are not unusual for a composite and are consistent with a late-A dwarf, combined with a late-G or early-K giant. The ultraviolet satellite clearly shows the presence of an A component, but its precise spectral type is difficult to assign. The IUE and TD-1 data suggest that the ultraviolet is dominated by light from an A5 V secondary and the visual from a GO III primary. This does not agree well with the most plausible model that fits the visual photometry. The peculiar nature of HR 6560's spectrum is most likely due to its composite nature.

The peculiar behaviour of the 5780 and 5797 DIBs in HD25137

NASA Technical Reports Server (NTRS)

Porceddu, Ignazio; Benvenuti, P.

1994-01-01

The interstellar environment close to the high latitude molecular cloud Lynds 1569 (L1569, Lynds 1962), also known as MBM 18 (Magnani, Blitz and Mundy, 1985), has been analyzed by Penrase et al. (1990) and Penrase (1993). Their observations of the CH, CH(sup+), and CN molecular features, are consistent with a region having a high molecular and reduced dust content. They also observed the background star HD 24263- located 8 degrees far from the center of L1569 - reporting a CH rich line of sight and the presence of two intervening clouds from a sodium lines spectra. The infrared excess which has been revealed by the IRAS survey at 12 microns might suggest the presence of PAH's molecules, the well know candidate for the Unidentified Infrared Bands and Diffuse Interstellar Bands. This interesting scenario led to the investigation of the behavior of the diffuse interstellar bands toward HD 25137, which is supposed to be a background object for L1569 (Penrase et al., 1990); as well as the field star HD 24263. As part of a wider observational program devoted to study the HLC's special environments, the observations of the diffuse interstellar bands (DIB's) at 5780 and 5797 lambda lambda in the direction of the two above mentioned stars, HD 24263 and HD 25137 are presented here.

Effects of HD-tDCS on memory and metamemory for general knowledge questions that vary by difficulty

PubMed Central

Chua, Elizabeth F.; Ahmed, Rifat; Garcia, Sandry

2016-01-01

Background The ability to monitor one’s own memory is an important feature of normal memory and is an aspect of ‘metamemory’. Lesion studies have shown dissociations between memory and metamemory, but only single dissociations have been shown using transcranial direct current stimulation (tDCS). One potential reason that only single dissociations have been shown is that tDCS effects may be moderated by task difficulty. Objective/Hypothesis We used high definition (HD) tDCS to test for dissociable roles of the dorsolateral prefrontal cortex (DLPFC) and anterior temporal lobe (ATL) in semantic long-term memory and metamemory tasks. We also tested whether general knowledge question difficulty moderated the effects of HD-tDCS. Methods Across 3 sessions, participants received active HD-tDCS over the left DLPFC or left ATL, or sham HD-tDCS during general knowledge recall and recognition tests, and a ‘feeling-of-knowing’ metamemory task. General knowledge questions were blocked by difficulty. Repeated measures ANOVAs were used to examine the effects of HD-tDCS on memory and metamemory tasks by memory question difficulty. Results HD-tDCS over the ATL led to improved recall compared to DLPFC and sham HD-tDCS, and this occurred only for medium difficulty questions. In contrast, for non-recalled questions, HD-tDCS over the DLPFC led to improved recognition accuracy and improved feeling-of-knowing accuracy compared to ATL and sham HD-tDCS, and this was not moderated by memory question difficulty. Conclusion(s) HD-tDCS can be used to dissociate the roles of the ATL and DLPFC in different memory and ‘metamemory’ tasks. The effects of HD-tDCS on task may be moderated by task difficulty, depending on the nature of the task and site of stimulation. PMID:27876306

Effects of HD-tDCS on memory and metamemory for general knowledge questions that vary by difficulty.

PubMed

Chua, Elizabeth F; Ahmed, Rifat; Garcia, Sandry M

The ability to monitor one's own memory is an important feature of normal memory and is an aspect of 'metamemory'. Lesion studies have shown dissociations between memory and metamemory, but only single dissociations have been shown using transcranial direct current stimulation (tDCS). One potential reason that only single dissociations have been shown is that tDCS effects may be moderated by task difficulty. We used high definition (HD) tDCS to test for dissociable roles of the dorsolateral prefrontal cortex (DLPFC) and anterior temporal lobe (ATL) in semantic long-term memory and metamemory tasks. We also tested whether general knowledge question difficulty moderated the effects of HD-tDCS. Across 3 sessions, participants received active HD-tDCS over the left DLPFC or left ATL, or sham HD-tDCS during general knowledge recall and recognition tests, and a 'feeling-of-knowing' metamemory task. General knowledge questions were blocked by difficulty. Repeated measures ANOVAs were used to examine the effects of HD-tDCS on memory and metamemory tasks by memory question difficulty. HD-tDCS over the ATL led to improved recall compared to DLPFC and sham HD-tDCS, and this occurred only for medium difficulty questions. In contrast, for non-recalled questions, HD-tDCS over the DLPFC led to improved recognition accuracy and improved feeling-of-knowing accuracy compared to ATL and sham HD-tDCS, and this was not moderated by memory question difficulty. HD-tDCS can be used to dissociate the roles of the ATL and DLPFC in different memory and 'metamemory' tasks. The effects of HD-tDCS on task may be moderated by task difficulty, depending on the nature of the task and site of stimulation. Copyright © 2016 Elsevier Inc. All rights reserved.

Phosphorylation Affects DNA-Binding of the Senescence-Regulating bZIP Transcription Factor GBF1

PubMed Central

Smykowski, Anja; Fischer, Stefan M.; Zentgraf, Ulrike

2015-01-01

Massive changes in the transcriptome of Arabidopsis thaliana during onset and progression of leaf senescence imply a central role for transcription factors. While many transcription factors are themselves up- or down-regulated during senescence, the bZIP transcription factor G-box-binding factor 1 (GBF1/bZIP41) is constitutively expressed in Arabidopsis leaf tissue but at the same time triggers the onset of leaf senescence, suggesting posttranscriptional mechanisms for senescence-specific GBF1 activation. Here we show that GBF1 is phosphorylated by the threonine/serine CASEIN KINASE II (CKII) in vitro and that CKII phosphorylation had a negative effect on GBF1 DNA-binding to G-boxes of two direct target genes, CATALASE2 and RBSCS1a. Phosphorylation mimicry at three serine positions in the basic region of GBF1 also had a negative effect on DNA-binding. Kinase assays revealed that CKII phosphorylates at least one serine in the basic domain but has additional phosphorylation sites outside this domain. Two different ckII α subunit1 and one α subunit2 T-DNA insertion lines showed no visible senescence phenotype, but in all lines the expression of the senescence marker gene SAG12 was remarkably diminished. A model is presented suggesting that senescence-specific GBF1 activation might be achieved by lowering the phosphorylation of GBF1 by CKII. PMID:27135347

Localization of the Kinesin-like Protein Xklp2 to Spindle Poles Requires a Leucine Zipper, a Microtubule-associated Protein, and Dynein

PubMed Central

Wittmann, Torsten; Boleti, Haralabia; Antony, Claude; Karsenti, Eric; Vernos, Isabelle

1998-01-01

Xklp2 is a plus end–directed Xenopus kinesin-like protein localized at spindle poles and required for centrosome separation during spindle assembly in Xenopus egg extracts. A glutathione-S-transferase fusion protein containing the COOH-terminal domain of Xklp2 (GST-Xklp2-Tail) was previously found to localize to spindle poles (Boleti, H., E. Karsenti, and I. Vernos. 1996. Cell. 84:49–59). Now, we have examined the mechanism of localization of GST-Xklp2-Tail. Immunofluorescence and electron microscopy showed that Xklp2 and GST-Xklp2-Tail localize specifically to the minus ends of spindle pole and aster microtubules in mitotic, but not in interphase, Xenopus egg extracts. We found that dimerization and a COOH-terminal leucine zipper are required for this localization: a single point mutation in the leucine zipper prevented targeting. The mechanism of localization is complex and two additional factors in mitotic egg extracts are required for the targeting of GST-Xklp2-Tail to microtubule minus ends: (a) a novel 100-kD microtubule-associated protein that we named TPX2 (Targeting protein for Xklp2) that mediates the binding of GST-Xklp2-Tail to microtubules and (b) the dynein–dynactin complex that is required for the accumulation of GST-Xklp2-Tail at microtubule minus ends. We propose two molecular mechanisms that could account for the localization of Xklp2 to microtubule minus ends. PMID:9813089

The Mg II h and k interstellar lines in the spectrum of the G-type giant HD 156854

NASA Technical Reports Server (NTRS)

Gurzadian, G. A.; Cholakian, V. G.; Kondo, Y.; Shore, Steven N.; Terzian, Yervant

1990-01-01

The results of the measurements and analysis of the IUE observations of the 2800 Mg II doublet in the spectrum of HD 156854, a G9 III star, are presented. The relative power of the magnesium chromosphere, R(Mg) = 0.00001, is in agreement with the known data for giants of the same class. The emission profiles of this doublet present absorption cores, which are of interstellar origin. Taking into account the interstellar depletion of Mg, the derived density of interstellar hydrogen is n(H) = 0.001/cu cm, which agrees with the conclusion (Paresce 1984) about the possibility of large hydrogen concentrations in some directions of the Galaxy far from the sun.

Spectral Variability of the Herbig Ae/Be Star HD 37806

NASA Astrophysics Data System (ADS)

Pogodin, M. A.; Pavlovskiy, S. E.; Kozlova, O. V.; Beskrovnaya, N. G.; Alekseev, I. Yu.; Valyavin, G. G.

2018-03-01

Results are reported from a spectroscopic study of the Herbig Ae/Be star HD 37806 from 2009 through 2017 using high resolution spectrographs at the Crimean Astrophysical Observatory and the OAN SPM Observatory in Mexico. 72 spectra of this object near the Hα, Hβ, HeI 5876 and D NaI lines are analyzed. The following results were obtained: 1. The type of spectral profile of the Hα line can change from P Cyg III to double emission and vice versa over a time scale on the order of a month. 2. Narrow absorption components are observed in the profiles of the Hα and D NaI lines with radial velocities that vary over a characteristic time on the order of a day. 3. On some days, the profiles of the Hβ, HeI 5876, and D NaI lines show signs of accretion of matter to the star with a characteristic lifetime of a few days. A possible interpretation of these phenomena was considered. The transformation of the Hα profile may be related to a change in the outer latitudinal width of the boundary of the wind zone. The narrow variable absorption lines may be caused by the rotation of local azimuthal inhomogeneities in the wind zone owing to the interaction of the disk with the star's magnetosphere in a propeller regime. Several current theoretical papers that predict the formation of similar inhomogeneous wind structures were examined. It is suggested that the episodes with signs of accretion in the spectral line profiles cannot be a consequence of the modulation of these profiles by the star's rotation but are more likely caused by sudden, brief changes in the accretion rate. These spectral observations of HD 37806 should be continued in a search for cyclical variability in the spectral parameters in order to identify direct signs of magnetospheric accretion and detect possible binary behavior in this object.

Direct Spectrum of the Benchmark T Dwarf HD 19467 B

NASA Astrophysics Data System (ADS)

Crepp, Justin R.; Rice, Emily L.; Veicht, Aaron; Aguilar, Jonathan; Pueyo, Laurent; Giorla, Paige; Nilsson, Ricky; Luszcz-Cook, Statia H.; Oppenheimer, Rebecca; Hinkley, Sasha; Brenner, Douglas; Vasisht, Gautam; Cady, Eric; Beichman, Charles A.; Hillenbrand, Lynne A.; Lockhart, Thomas; Matthews, Christopher T.; Roberts, Lewis C., Jr.; Sivaramakrishnan, Anand; Soummer, Remi; Zhai, Chengxing

2015-01-01

HD 19467 B is presently the only directly imaged T dwarf companion known to induce a measurable Doppler acceleration around a solar-type star. We present spectroscopy measurements of this important benchmark object taken with the Project 1640 integral field unit at Palomar Observatory. Our high-contrast R ≈ 30 observations obtained simultaneously across the JH bands confirm the cold nature of the companion as reported from the discovery article and determine its spectral type for the first time. Fitting the measured spectral energy distribution to SpeX/IRTF T dwarf standards and synthetic spectra from BT-Settl atmospheric models, we find that HD 19467 B is a T5.5 ± 1 dwarf with effective temperature T_eff=978+20-43 K. Our observations reveal significant methane absorption affirming its substellar nature. HD 19467 B shows promise to become the first T dwarf that simultaneously reveals its mass, age, and metallicity independent from the spectrum of light that it emits.

Trp zipper folding kinetics by molecular dynamics and temperature-jump spectroscopy

PubMed Central

Snow, Christopher D.; Qiu, Linlin; Du, Deguo; Gai, Feng; Hagen, Stephen J.; Pande, Vijay S.

2004-01-01

We studied the microsecond folding dynamics of three β hairpins (Trp zippers 1–3, TZ1–TZ3) by using temperature-jump fluorescence and atomistic molecular dynamics in implicit solvent. In addition, we studied TZ2 by using time-resolved IR spectroscopy. By using distributed computing, we obtained an aggregate simulation time of 22 ms. The simulations included 150, 212, and 48 folding events at room temperature for TZ1, TZ2, and TZ3, respectively. The all-atom optimized potentials for liquid simulations (OPLSaa) potential set predicted TZ1 and TZ2 properties well; the estimated folding rates agreed with the experimentally determined folding rates and native conformations were the global potential-energy minimum. The simulations also predicted reasonable unfolding activation enthalpies. This work, directly comparing large simulated folding ensembles with multiple spectroscopic probes, revealed both the surprising predictive ability of current models as well as their shortcomings. Specifically, for TZ1–TZ3, OPLS for united atom models had a nonnative free-energy minimum, and the folding rate for OPLSaa TZ3 was sensitive to the initial conformation. Finally, we characterized the transition state; all TZs fold by means of similar, native-like transition-state conformations. PMID:15020773

Small Maf proteins (MafF, MafG, MafK): History, structure and function.

PubMed

Katsuoka, Fumiki; Yamamoto, Masayuki

2016-07-25

The small Maf proteins (sMafs) are basic region leucine zipper (bZIP)-type transcription factors. The basic region of the Maf family is unique among the bZIP factors, and it contributes to the distinct DNA-binding mode of this class of proteins. MafF, MafG and MafK are the three vertebrate sMafs, and no functional differences have been observed among them in terms of their bZIP structures. sMafs form homodimers by themselves, and they form heterodimers with cap 'n' collar (CNC) proteins (p45 NF-E2, Nrf1, Nrf2, and Nrf3) and also with Bach proteins (Bach1 and Bach2). Because CNC and Bach proteins cannot bind to DNA as monomers, sMafs are indispensable partners that are required by CNC and Bach proteins to exert their functions. sMafs lack the transcriptional activation domain; hence, their homodimers act as transcriptional repressors. In contrast, sMafs participate in transcriptional activation or repression depending on their heterodimeric partner molecules and context. Mouse genetic analyses have revealed that various biological pathways are under the regulation of CNC-sMaf heterodimers. In this review, we summarize the history and current progress of sMaf studies in relation to their partners. Copyright © 2016 Elsevier B.V. All rights reserved.

Comparison of NOx emissions from China III and China IV in-use diesel trucks based on on-road measurements

NASA Astrophysics Data System (ADS)

Yao, Zhiliang; Wu, Bobo; Wu, Yunong; Cao, Xinyue; Jiang, Xi

2015-12-01

To mitigate NOx and other emissions from diesel vehicles, China I, China II, China III and China IV emissions standards for new vehicles have been implemented nationwide. However, recent on-road measurements using a portable emission measurement system (PEMS) have revealed no significant reductions in the NOx emissions factors of diesel trucks due to the change from China II emissions standards to the more stringent China III standards. Thus, it is important to understand the effect of the China IV emissions standard on NOx emissions. In this study, nine China III and nine China IV diesel trucks of three sizes (light-duty diesel trucks (LDDTs), medium-duty diesel trucks (MDDTs) and heavy-duty diesel trucks (HDDTs)) were tested on real roads in Beijing using a PEMS. Compared to the tested China III diesel trucks, the China IV diesel trucks showed significant reductions of the average NOx emissions factors in terms of both distance travelled and fuel consumption. However, the driving conditions had an important impact on the reduction. Under non-highway driving (NHD), several of the tested China IV diesel trucks experienced no reduction or an increase in NOx emissions compared to their China III counterparts. The NOx emissions factors of the 18 tested diesel trucks under NHD were on average 1.5-times greater than those under highway driving (HD), and the effects on NOx emissions removal from China III to China IV diesel trucks were greater under HD than under NHD. In addition, no significant reduction of NOx based on fuel consumption for China IV diesel trucks was observed for MDDTs and HDDTs compared to the test results for similar China II vehicles reported in a previous study. To reduce NOx emissions in China, additional control measures of vehicular NOx emissions should be formulated.

Carbon and nitrogen abundances in the supergiants HD 93840 and zeta Per

NASA Technical Reports Server (NTRS)

Massa, Derck; Altner, Bruce; Wynne, David; Lamers, H. J. G. L. M.

1990-01-01

The BN supergiant HD 93840 is shown to have the same temperature and surface gravity as the normal Bi Ib zeta Per. Differential abundance analysis of their C 4 and N 5 wind line profiles are found. The results are independent of the usual model atmosphere analyses and, therefore, a valuable check on them. Ratios for the C and N surface abundances in HD 93840 compared to Per of 1:10 and 4.6:1 are found respectively. By introducing a simple model for the compositions of both atmospheres the fraction of material in each atmosphere which has undergone CNO processing, more than 90 percent for HD 93840 and less than about 15 percent for zeta Per, is derived.

The Stroop Revisited: A Meta-Analysis of Interference Control in AD/HD

ERIC Educational Resources Information Center

Van Mourik, Rosa; Oosterlaan, Jaap; Sergeant, Joseph A.

2005-01-01

Background: An inhibition deficit, including poor interference control, has been implicated as one of the core deficits in AD/HD. Interference control is clinically measured by the Stroop Colour-Word Task. The aim of this meta-analysis was to investigate the strength of an interference deficit in AD/HD as measured by the Stroop Colour-Word Task…

A type III-B CRISPR-Cas effector complex mediating massive target DNA destruction.

PubMed

Han, Wenyuan; Li, Yingjun; Deng, Ling; Feng, Mingxia; Peng, Wenfang; Hallstrøm, Søren; Zhang, Jing; Peng, Nan; Liang, Yun Xiang; White, Malcolm F; She, Qunxin

2017-02-28

The CRISPR (clustered regularly interspaced short palindromic repeats) system protects archaea and bacteria by eliminating nucleic acid invaders in a crRNA-guided manner. The Sulfolobus islandicus type III-B Cmr-α system targets invading nucleic acid at both RNA and DNA levels and DNA targeting relies on the directional transcription of the protospacer in vivo. To gain further insight into the involved mechanism, we purified a native effector complex of III-B Cmr-α from S. islandicus and characterized it in vitro. Cmr-α cleaved RNAs complementary to crRNA present in the complex and its ssDNA destruction activity was activated by target RNA. The ssDNA cleavage required mismatches between the 5΄-tag of crRNA and the 3΄-flanking region of target RNA. An invader plasmid assay showed that mutation either in the histidine-aspartate acid (HD) domain (a quadruple mutation) or in the GGDD motif of the Cmr-2α protein resulted in attenuation of the DNA interference in vivo. However, double mutation of the HD motif only abolished the DNase activity in vitro. Furthermore, the activated Cmr-α binary complex functioned as a highly active DNase to destroy a large excess DNA substrate, which could provide a powerful means to rapidly degrade replicating viral DNA. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

Abundance analysis of roAp stars. IV. HD24712

NASA Astrophysics Data System (ADS)

Ryabchikova, T. A.; Landstreet, J. D.; Gelbmann, M. J.; Bolgova, G. T.; Tsymbal, V. V.; Weiss, W. W.

1997-11-01

We present the first abundance analysis of the rapidly oscillating chemically peculiar star HD24712, and determine a T_eff,=7250K, log {g},=4.3, and xi_t ,=1kms(-1) . Microturbulence seems to be entirely simulated by a magnetic field with a polar field strength of 4.4kG and of dipolar structure, both of which are supported by our polarimetric observations. Rotation of HD24712 and a spotty surface distribution of the elements result in different mean abundances for different (magnetic) phases. Our results do not support the hypothesis of a monotonic correlation between the amplitude of abundance variations and the atomic number Z, and we present arguments in favour of one of the rotation periods (Prot=12\\fd 4610) discussed in the literature. Rare earth elements are the most overabundant elements relative to the sun, and they have the largest abundance amplitude during a rotation cycle; only Mg has a larger amplitude. For HD24712 we find a clear overabundance of Co while most of the other iron peak elements are underabundant. A comparison of the abundance pattern with the other three roAp stars analyzed so far by us concludes the paper. A systematic difference between surface gravities obtained from spectroscopy and from both asteroseismology and evolutionary tracks is found for the roAp stars HD 24712, alpha Cir, and gamma Equ. Based on observations obtained with the Canada-France-Hawaii telescope, operated by the National Research Council of Canada, the Centre Centre National de la Recherche Scientifique de France, and the University of Hawaii, and on observations obtained at CARSO, Las Campanas, Chile

Contact-dependent killing by Caulobacter crescentus via cell surface-associated, glycine zipper proteins

PubMed Central

García-Bayona, Leonor; Guo, Monica S; Laub, Michael T

2017-01-01

Most bacteria are in fierce competition with other species for limited nutrients. Some bacteria can kill nearby cells by secreting bacteriocins, a diverse group of proteinaceous antimicrobials. However, bacteriocins are typically freely diffusible, and so of little value to planktonic cells in aqueous environments. Here, we identify an atypical two-protein bacteriocin in the α-proteobacterium Caulobacter crescentus that is retained on the surface of producer cells where it mediates cell contact-dependent killing. The bacteriocin-like proteins CdzC and CdzD harbor glycine-zipper motifs, often found in amyloids, and CdzC forms large, insoluble aggregates on the surface of producer cells. These aggregates can drive contact-dependent killing of other organisms, or Caulobacter cells not producing the CdzI immunity protein. The Cdz system uses a type I secretion system and is unrelated to previously described contact-dependent inhibition systems. However, Cdz-like systems are found in many bacteria, suggesting that this form of contact-dependent inhibition is common. DOI: http://dx.doi.org/10.7554/eLife.24869.001 PMID:28323618

Dual leucine zipper kinase-dependent PERK activation contributes to neuronal degeneration following insult

PubMed Central

Larhammar, Martin; Huntwork-Rodriguez, Sarah; Jiang, Zhiyu; Solanoy, Hilda; Sengupta Ghosh, Arundhati; Wang, Bei; Kaminker, Joshua S; Huang, Kevin; Eastham-Anderson, Jeffrey; Siu, Michael; Modrusan, Zora; Farley, Madeline M; Tessier-Lavigne, Marc; Lewcock, Joseph W; Watkins, Trent A

2017-01-01

The PKR-like endoplasmic reticulum kinase (PERK) arm of the Integrated Stress Response (ISR) is implicated in neurodegenerative disease, although the regulators and consequences of PERK activation following neuronal injury are poorly understood. Here we show that PERK signaling is a component of the mouse MAP kinase neuronal stress response controlled by the Dual Leucine Zipper Kinase (DLK) and contributes to DLK-mediated neurodegeneration. We find that DLK-activating insults ranging from nerve injury to neurotrophin deprivation result in both c-Jun N-terminal Kinase (JNK) signaling and the PERK- and ISR-dependent upregulation of the Activating Transcription Factor 4 (ATF4). Disruption of PERK signaling delays neurodegeneration without reducing JNK signaling. Furthermore, DLK is both sufficient for PERK activation and necessary for engaging the ISR subsequent to JNK-mediated retrograde injury signaling. These findings identify DLK as a central regulator of not only JNK but also PERK stress signaling in neurons, with both pathways contributing to neurodegeneration. DOI: http://dx.doi.org/10.7554/eLife.20725.001 PMID:28440222

A Time-dependant atmospheric model of HD209458b

NASA Astrophysics Data System (ADS)

Iro, N.; Bézard, B.; Guillot, T.

2004-11-01

Charbonneau et al. (2002) conducted HST spectroscopic observations of HD209458 centered on the sodium doublet at 589.3 nm. An absorption feature was found, interpreted as an absorption from the sodium in the planet's atmosphere. However, this feature is weaker than predicted by static radiative equilibrium atmospheric models of HD209458b. We present a time-dependent radiative model of the atmosphere of HD209458b and investigate its thermal structure and chemical composition. Time-dependent temperature profiles are calculated, assuming a constant-with-height zonal wind, modelled as a solid body rotation. We predict day-night variations of the effective temperature of ˜600 K, for an equatorial rotation rate of 1 km s-1, in good agreement with the predictions by Showman & Guillot, 2002. At high altitudes (mbar pressures or less), the night temperatures are low enough to allow sodium to condense into Na2S. Synthetic transit spectra of the visible Na doublet show a much weaker sodium absorption on the morning limb than on the evening limb. The calculated dimming of the sodium feature during a planetary transit agrees with the value reported by Charbonneau et al. (2002).

Modeling the HD 32297 Debris Disk With Far-Infrared Herschel Data

NASA Technical Reports Server (NTRS)

Donaldson, J.K.; Lebreton, J.; Roberge, A.; Augereau, J.-C.; Krivov, A. V.

2013-01-01

HD 32297 is a young A-star (approx. 30 Myr) 112 pc away with a bright edge-on debris disk that has been resolved in scattered light. We observed the HD 32297 debris disk in the far-infrared and sub-millimeter with the Herschel Space Observatory PACS and SPIRE instruments, populating the spectral energy distribution (SED) from 63 to 500 micron..We aimed to determine the composition of dust grains in the HD 32297 disk through SED modeling, using geometrical constraints from the resolved imaging to break the degeneracies inherent in SED modeling. We found the best fitting SED model has two components: an outer ring centered around 110 AU, seen in the scattered light images, and an inner disk near the habitable zone of the star. The outer disk appears to be composed of grains>2 micron consisting of silicates, carbonaceous material, and water ice with an abundance ratio of 1:2:3 respectively and 90% porosity. These grains appear consistent with cometary grains, implying the underlying planetesimal population is dominated by comet-like bodies. We also discuss the 3.7 sigma detection of [C ii] emission at 158 micron with the Herschel PACS instrument, making HD 32297 one of only a handful of debris disks with circumstellar gas detected

Conformations of cationized linear oligosaccharides revealed by FTMS combined with in-ESI H/D exchange.

PubMed

Kostyukevich, Yury; Kononikhin, Alexey; Popov, Igor; Nikolaev, Eugene

2015-10-01