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Sample records for wheat d-genome progenitor

  1. Dissecting miRNAs in Wheat D Genome Progenitor, Aegilops tauschii.

    PubMed

    Akpinar, Bala A; Budak, Hikmet

    2016-01-01

    As the post-transcriptional regulators of gene expression, microRNAs or miRNAs comprise an integral part of understanding how genomes function. Although miRNAs have been a major focus of recent efforts, miRNA research is still in its infancy in most plant species. Aegilops tauschii, the D genome progenitor of bread wheat, is a wild diploid grass exhibiting remarkable population diversity. Due to the direct ancestry and the diverse gene pool, A. tauschii is a promising source for bread wheat improvement. In this study, a total of 87 Aegilops miRNA families, including 51 previously unknown, were computationally identified both at the subgenomic level, using flow-sorted A. tauschii 5D chromosome, and at the whole genome level. Predictions at the genomic and subgenomic levels suggested A. tauschii 5D chromosome as rich in pre-miRNAs that are highly associated with Class II DNA transposons. In order to gain insights into miRNA evolution, putative 5D chromosome miRNAs were compared to its modern ortholog, Triticum aestivum 5D chromosome, revealing that 48 of the 58 A. tauschii 5D miRNAs were conserved in orthologous T. aestivum 5D chromosome. The expression profiles of selected miRNAs (miR167, miR5205, miR5175, miR5523) provided the first experimental evidence for miR5175, miR5205 and miR5523, and revealed differential expressional changes in response to drought in different genetic backgrounds for miR167 and miR5175. Interestingly, while miR5523 coding regions were present and expressed as pre-miR5523 in both T. aestivum and A. tauschii, the expression of mature miR5523 was observed only in A. tauschii under normal conditions, pointing out to an interference at the downstream processing of pre-miR5523 in T. aestivum. Overall, this study expands our knowledge on the miRNA catalog of A. tauschii, locating a subset specifically to the 5D chromosome, with ample functional and comparative insight which should contribute to and complement efforts to develop drought tolerant

  2. Dissecting miRNAs in Wheat D Genome Progenitor, Aegilops tauschii

    PubMed Central

    Akpinar, Bala A.; Budak, Hikmet

    2016-01-01

    As the post-transcriptional regulators of gene expression, microRNAs or miRNAs comprise an integral part of understanding how genomes function. Although miRNAs have been a major focus of recent efforts, miRNA research is still in its infancy in most plant species. Aegilops tauschii, the D genome progenitor of bread wheat, is a wild diploid grass exhibiting remarkable population diversity. Due to the direct ancestry and the diverse gene pool, A. tauschii is a promising source for bread wheat improvement. In this study, a total of 87 Aegilops miRNA families, including 51 previously unknown, were computationally identified both at the subgenomic level, using flow-sorted A. tauschii 5D chromosome, and at the whole genome level. Predictions at the genomic and subgenomic levels suggested A. tauschii 5D chromosome as rich in pre-miRNAs that are highly associated with Class II DNA transposons. In order to gain insights into miRNA evolution, putative 5D chromosome miRNAs were compared to its modern ortholog, Triticum aestivum 5D chromosome, revealing that 48 of the 58 A. tauschii 5D miRNAs were conserved in orthologous T. aestivum 5D chromosome. The expression profiles of selected miRNAs (miR167, miR5205, miR5175, miR5523) provided the first experimental evidence for miR5175, miR5205 and miR5523, and revealed differential expressional changes in response to drought in different genetic backgrounds for miR167 and miR5175. Interestingly, while miR5523 coding regions were present and expressed as pre-miR5523 in both T. aestivum and A. tauschii, the expression of mature miR5523 was observed only in A. tauschii under normal conditions, pointing out to an interference at the downstream processing of pre-miR5523 in T. aestivum. Overall, this study expands our knowledge on the miRNA catalog of A. tauschii, locating a subset specifically to the 5D chromosome, with ample functional and comparative insight which should contribute to and complement efforts to develop drought tolerant

  3. A 4-gigabase physical map unlocks the structure and evolution of the complex genome of Aegilops tauschii, the wheat D-genome progenitor

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The current limitations in genome sequencing technology require the construction of physical maps for high-quality draft sequences of large plant genomes, such as that of Aegilops tauschii, the wheat D-genome progenitor. To construct a physical map of the Ae. tauschii genome, we fingerprinted 461,70...

  4. Physical mapping resources for large plant genomes: radiation hybrids for wheat D-genome progenitor Aegilops tauschii

    PubMed Central

    2012-01-01

    Background Development of a high quality reference sequence is a daunting task in crops like wheat with large (~17Gb), highly repetitive (>80%) and polyploid genome. To achieve complete sequence assembly of such genomes, development of a high quality physical map is a necessary first step. However, due to the lack of recombination in certain regions of the chromosomes, genetic mapping, which uses recombination frequency to map marker loci, alone is not sufficient to develop high quality marker scaffolds for a sequence ready physical map. Radiation hybrid (RH) mapping, which uses radiation induced chromosomal breaks, has proven to be a successful approach for developing marker scaffolds for sequence assembly in animal systems. Here, the development and characterization of a RH panel for the mapping of D-genome of wheat progenitor Aegilops tauschii is reported. Results Radiation dosages of 350 and 450 Gy were optimized for seed irradiation of a synthetic hexaploid (AABBDD) wheat with the D-genome of Ae. tauschii accession AL8/78. The surviving plants after irradiation were crossed to durum wheat (AABB), to produce pentaploid RH1s (AABBD), which allows the simultaneous mapping of the whole D-genome. A panel of 1,510 RH1 plants was obtained, of which 592 plants were generated from the mature RH1 seeds, and 918 plants were rescued through embryo culture due to poor germination (<3%) of mature RH1 seeds. This panel showed a homogenous marker loss (2.1%) after screening with SSR markers uniformly covering all the D-genome chromosomes. Different marker systems mostly detected different lines with deletions. Using markers covering known distances, the mapping resolution of this RH panel was estimated to be <140kb. Analysis of only 16 RH lines carrying deletions on chromosome 2D resulted in a physical map with cM/cR ratio of 1:5.2 and 15 distinct bins. Additionally, with this small set of lines, almost all the tested ESTs could be mapped. A set of 399 most informative RH

  5. A 4-gigabase physical map unlocks the structure and evolution of the complex genome of Aegilops tauschii, the wheat D-genome progenitor

    PubMed Central

    Luo, Ming-Cheng; Gu, Yong Q.; You, Frank M.; Deal, Karin R.; Ma, Yaqin; Hu, Yuqin; Huo, Naxin; Wang, Yi; Wang, Jirui; Chen, Shiyong; Jorgensen, Chad M.; Zhang, Yong; McGuire, Patrick E.; Pasternak, Shiran; Stein, Joshua C.; Ware, Doreen; Kramer, Melissa; McCombie, W. Richard; Kianian, Shahryar F.; Martis, Mihaela M.; Mayer, Klaus F. X.; Sehgal, Sunish K.; Li, Wanlong; Gill, Bikram S.; Bevan, Michael W.; Šimková, Hana; Doležel, Jaroslav; Weining, Song; Lazo, Gerard R.; Anderson, Olin D.; Dvorak, Jan

    2013-01-01

    The current limitations in genome sequencing technology require the construction of physical maps for high-quality draft sequences of large plant genomes, such as that of Aegilops tauschii, the wheat D-genome progenitor. To construct a physical map of the Ae. tauschii genome, we fingerprinted 461,706 bacterial artificial chromosome clones, assembled contigs, designed a 10K Ae. tauschii Infinium SNP array, constructed a 7,185-marker genetic map, and anchored on the map contigs totaling 4.03 Gb. Using whole genome shotgun reads, we extended the SNP marker sequences and found 17,093 genes and gene fragments. We showed that collinearity of the Ae. tauschii genes with Brachypodium distachyon, rice, and sorghum decreased with phylogenetic distance and that structural genome evolution rates have been high across all investigated lineages in subfamily Pooideae, including that of Brachypodieae. We obtained additional information about the evolution of the seven Triticeae chromosomes from 12 ancestral chromosomes and uncovered a pattern of centromere inactivation accompanying nested chromosome insertions in grasses. We showed that the density of noncollinear genes along the Ae. tauschii chromosomes positively correlates with recombination rates, suggested a cause, and showed that new genes, exemplified by disease resistance genes, are preferentially located in high-recombination chromosome regions. PMID:23610408

  6. Sequence polymorphism in polyploid wheat and their d-genome diploid ancestor.

    PubMed

    Caldwell, Katherine S; Dvorak, Jan; Lagudah, Evans S; Akhunov, Eduard; Luo, Ming-Cheng; Wolters, Petra; Powell, Wayne

    2004-06-01

    Sequencing was used to investigate the origin of the D genome of the allopolyploid species Triticum aestivum and Aegilops cylindrica. A 247-bp region of the wheat D-genome Xwye838 locus, encoding ADP-glucopyrophosphorylase, and a 326-bp region of the wheat D-genome Gss locus, encoding granule-bound starch synthase, were sequenced in a total 564 lines of hexaploid wheat (T. aestivum, genome AABBDD) involving all its subspecies and 203 lines of Aegilops tauschii, the diploid source of the wheat D genome. In Ae. tauschii, two SNP variants were detected at the Xwye838 locus and 11 haplotypes at the Gss locus. Two haplotypes with contrasting frequencies were found at each locus in wheat. Both wheat Xwye838 variants, but only one of the Gss haplotypes seen in wheat, were found among the Ae. tauschii lines. The other wheat Gss haplotype was not found in either Ae. tauschii or 70 lines of tetraploid Ae. cylindrica (genomes CCDD), which is known to hybridize with wheat. It is concluded that both T. aestivum and Ae. cylindrica originated recurrently, with at least two genetically distinct progenitors contributing to the formation of the D genome in both species. PMID:15238542

  7. A 4-gigbase physical map unlocks the structure and evolution of the complex genome of Aegilop tauschii, the wheat D-genome progenitor

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The genomes of wheat and its relatives in the tribe Triticeae are large, containing nearly 90% repetitive DNA, and some are polyploid. These genomes can currently be completely sequenced only by the ordered-clone genome sequencing approach, which reduces the complexity of sequence assembly from th...

  8. Fine mapping of Hch1, the causal D-genome gene for hybrid chlorosis in interspecific crosses between tetraploid wheat and Aegilops tauschii.

    PubMed

    Hirao, Kana; Nishijima, Ryo; Sakaguchi, Kohei; Takumi, Shigeo

    2016-03-23

    Hybrid chlorosis, one of the reproductive barriers between tetraploid wheat and its D-genome progenitor, Aegilops tauschii, inhibits normal growth of synthetic wheat hexaploids. Hybrid chlorosis appears to be due to an epistatic interaction of two loci from the AB and D wheat genomes. Our previous study assigned the causal D-genome gene for hybrid chlorosis, Hch1, to the short arm of chromosome 7D. Here, we constructed a fine map of 7DS near Hch1 using 280 F2 individuals from a cross of two wheat synthetic lines, one showing normal growth and the other showing hybrid chlorosis. The hybrid chlorosis phenotype was controlled by a single dominant allele of the Hch1 locus in the synthetic hexaploids. Hch1 was closely linked to four new markers within 0.2 cM, and may be localized near or within the two Ae. tauschii scaffolds containing the linked markers on 7DS. Comparative analysis of the Hch1 chromosomal region for Ae. tauschii, barley and Brachypodium showed that a local inversion occurred in the region proximal to Hch1 during the divergence between barley and Ae. tauschii, and that the Hch1 region on wheat 7DS is syntenic to Brachypodium chromosome 1. These observations provide useful information for further studies toward map-based cloning of Hch1. PMID:26687862

  9. Regions of the bread wheat D genome associated with variation in key photosynthesis traits and shoot biomass under both well watered and water deficient conditions.

    PubMed

    Osipova, Svetlana; Permyakov, Alexey; Permyakova, Marina; Pshenichnikova, Tatyana; Verkhoturov, Vasiliy; Rudikovsky, Alexandr; Rudikovskaya, Elena; Shishparenok, Alexandr; Doroshkov, Alexey; Börner, Andreas

    2016-05-01

    A quantitative trait locus (QTL) approach was taken to reveal the genetic basis in wheat of traits associated with photosynthesis during a period of exposure to water deficit stress. The performance, with respect to shoot biomass, gas exchange and chlorophyll fluorescence, leaf pigment content and the activity of various ascorbate-glutathione cycle enzymes and catalase, of a set of 80 wheat lines, each containing a single chromosomal segment introgressed from the bread wheat D genome progenitor Aegilops tauschii, was monitored in plants exposed to various water regimes. Four of the seven D genome chromosomes (1D, 2D, 5D, and 7D) carried clusters of both major (LOD >3.0) and minor (LOD between 2.0 and 3.0) QTL. A major QTL underlying the activity of glutathione reductase was located on chromosome 2D, and another, controlling the activity of ascorbate peroxidase, on chromosome 7D. A region of chromosome 2D defined by the microsatellite locus Xgwm539 and a second on chromosome 7D flanked by the marker loci Xgwm1242 and Xgwm44 harbored a number of QTL associated with the water deficit stress response. PMID:26374127

  10. [Influence of D genome of wheat on expression of novel type spike branching in hybrid populations of 171ACS line].

    PubMed

    Alieva, A J; Aminov, N Kh

    2013-11-01

    A 171ACS line (AABBDD, 2n = 6x = 42) has been crossed with the tetra- (AABB and AAGG, 2n = 4x = 28) and octoploid (AAAABBGG, 2n = 8x = 56) wheat species without the D genome, as well as with hexaploid (AABBDD and AAGGDD, 2n = 6x = 42) wheat species and tetra- (AADD, 2n = 4x = 28) and hexaploid (AADDSS, 2n = 6x = 42) amphidiploids that have the D genome. The inheritance of a novel type of spike branching in these obtained hybrid populations F1-F3 was studied. According to the results of a morphogenetic analysis of hybrid populations derived from crossings between 171ACS and wheat species without the D genome, the novel type of branching was found to be controlled by a single recessive gene (although a phenotype of the 171ACS line gives a handle for a doubt about occurrence of the second gene) and the 171ACS line is a source of gene of the novel type branching. However, not a single branched spike plant was observed in hybrid populations that were produced by crosses of the 171ACS line with wheat species, as well as with amphidiploids that have the D genome. This result also experimentally confirmed the inhibitor effect of chromosomes of the D genome on the expression of the spike-branching trait. The appearance of branched spike forms, together with normal spiked plants in hybrid populations of the 171ACS line and T. araraticum Jakubz. (AAGG) or T. fungicidum Zhuk. (AAAABBGG) confirmed that, as opposed to the D genome, neither genome G nor genome B demonstrated the inhibition of the expression of the spike-branching trait. In conclusion, keeping in mind that branching is exhibited in hybrid progenies obtained from crosses between the 171ACS line and wheat species with AABB and AAGG genomes, it can be said that this gene belongs to the A genome. PMID:25470929

  11. [Influence of D genome of wheat on expression of novel type spike branching in hybrid populations of 171ACS line].

    PubMed

    2013-11-01

    A 171ACS line (AABBDD, 2n = 6x = 42) has been crossed with the tetra- (AABB and AAGG, 2n = 4x = 28) and octoploid (AAAABBGG, 2n = 8x = 56) wheat species without the D genome, as well as with hexaploid (AABBDD and AAGGDD, 2n = 6x = 42) wheat species and tetra- (AADD, 2n = 4x = 28) and hexaploid (AADDSS, 2n = 6x = 42) amphidiploids that have the D genome. The inheritance of a novel type of spike branching in these obtained hybrid populations F1-F3 was studied. According to the results of a morphogenetic analysis of hybrid populations derived from crossings between 171ACS and wheat species without the D genome, the novel type of branching was found to be controlled by a single recessive gene (although a phenotype of the 171ACS line gives a handle for a doubt about occurrence of the second gene) and the 171ACS line is a source of gene of the novel type branching. However, not a single branched spike plant was observed in hybrid populations that were produced by crosses of the 171ACS line with wheat species, as well as with amphidiploids that have the D genome. This result also experimentally confirmed the inhibitor effect of chromosomes of the D genome on the expression of the spike-branching trait. The appearance of branched spike forms, together with normal spiked plants in hybrid populations of the 171ACS line and T. araraticum Jakubz. (AAGG) or T. fungicidum Zhuk. (AAAABBGG) confirmed that, as opposed to the D genome, neither genome G nor genome B demonstrated the inhibition of the expression of the spike-branching trait. In conclusion, keeping in mind that branching is exhibited in hybrid progenies obtained from crosses between the 171ACS line and wheat species with AABB and AAGG genomes, it can be said that this gene belongs to the A genome. PMID:25508556

  12. THE WHEAT D-GENOME HMW-GLUTENIN LOCUS:BAC SEQUENCING, GENE DISTRIBUTION, AND RETROTRANSPOSON CLUSTERS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A bacterial-artificial-chromosome (BAC) clone from the genome of Triticum tauschii, the D-genome ancestor of hexaploid bread wheat, was sequenced and the presence of the two paralogous x- and y- type high-molecular-weight (HMW) glutenin genes of the Glu-D1 locus was confirmed. These two genes occur...

  13. Draft genome of the wheat A-genome progenitor Triticum urartu.

    PubMed

    Ling, Hong-Qing; Zhao, Shancen; Liu, Dongcheng; Wang, Junyi; Sun, Hua; Zhang, Chi; Fan, Huajie; Li, Dong; Dong, Lingli; Tao, Yong; Gao, Chuan; Wu, Huilan; Li, Yiwen; Cui, Yan; Guo, Xiaosen; Zheng, Shusong; Wang, Biao; Yu, Kang; Liang, Qinsi; Yang, Wenlong; Lou, Xueyuan; Chen, Jie; Feng, Mingji; Jian, Jianbo; Zhang, Xiaofei; Luo, Guangbin; Jiang, Ying; Liu, Junjie; Wang, Zhaobao; Sha, Yuhui; Zhang, Bairu; Wu, Huajun; Tang, Dingzhong; Shen, Qianhua; Xue, Pengya; Zou, Shenhao; Wang, Xiujie; Liu, Xin; Wang, Famin; Yang, Yanping; An, Xueli; Dong, Zhenying; Zhang, Kunpu; Zhang, Xiangqi; Luo, Ming-Cheng; Dvorak, Jan; Tong, Yiping; Wang, Jian; Yang, Huanming; Li, Zhensheng; Wang, Daowen; Zhang, Aimin; Wang, Jun

    2013-04-01

    Bread wheat (Triticum aestivum, AABBDD) is one of the most widely cultivated and consumed food crops in the world. However, the complex polyploid nature of its genome makes genetic and functional analyses extremely challenging. The A genome, as a basic genome of bread wheat and other polyploid wheats, for example, T. turgidum (AABB), T. timopheevii (AAGG) and T. zhukovskyi (AAGGA(m)A(m)), is central to wheat evolution, domestication and genetic improvement. The progenitor species of the A genome is the diploid wild einkorn wheat T. urartu, which resembles cultivated wheat more extensively than do Aegilops speltoides (the ancestor of the B genome) and Ae. tauschii (the donor of the D genome), especially in the morphology and development of spike and seed. Here we present the generation, assembly and analysis of a whole-genome shotgun draft sequence of the T. urartu genome. We identified protein-coding gene models, performed genome structure analyses and assessed its utility for analysing agronomically important genes and for developing molecular markers. Our T. urartu genome assembly provides a diploid reference for analysis of polyploid wheat genomes and is a valuable resource for the genetic improvement of wheat. PMID:23535596

  14. Spontaneous and Divergent Hexaploid Triticales Derived from Common Wheat × Rye by Complete Elimination of D-Genome Chromosomes

    PubMed Central

    Wang, Changyou; Ji, Wanquan

    2015-01-01

    Background Hexaploid triticale could be either synthesized by crossing tetraploid wheat with rye, or developed by crossing hexaploid wheat with a hexaploid triticale or an octoploid triticale. Methodology/Principal Findings Here two hexaploid triticales with great morphologic divergence derived from common wheat cultivar M8003 (Triticum aestivum L.) × Austrian rye (Secale cereale L.) were reported, exhibiting high resistance for powdery mildew and stripe rust and potential for wheat improvement. Sequential fluorescence in situ hybridization (FISH) and genomic in situ hybridization (GISH) karyotyping revealed that D-genome chromosomes were completely eliminated and the whole A-genome, B-genome and R-genome chromosomes were retained in both lines. Furthermore, plentiful alterations of wheat chromosomes including 5A and 7B were detected in both triticales and additionally altered 5B, 7A chromosome and restructured chromosome 2A was assayed in N9116H and N9116M, respectively, even after selfing for several decades. Besides, meiotic asynchrony was displayed and a variety of storage protein variations were assayed, especially in the HMW/LMW-GS region and secalins region in both triticales. Conclusion This study confirms that whole D-genome chromosomes could be preferentially eliminated in the hybrid of common wheat × rye, “genome shock” was accompanying the allopolyploidization of nascent triticales, and great morphologic divergence might result from the genetic variations. Moreover, new hexaploid triticale lines contributing potential resistance resources for wheat improvement were produced. PMID:25781330

  15. [Evolution study of wheat (Tritium aestivum L.) A, B and D genome based on DNA sequence similarity].

    PubMed

    Yu, B L; Huang, Z F; Zhou, W J; Zhang, W J

    2001-01-01

    Tritium aestivum L., and its four potential origin species T. urartu T., T. monococcum L., Ae. squarrosa L. and T. dicoccum S., were amplified with MWG913, a STS marker located in 1H chromosome of barley. Those products are cloned and sequenced. By the discrepancies of these sequences, we have obtained some evidences about the origin of wheat A, B, D genomes at molecular level. The results showed that the studied sequence in A genomes of Tritium aestivum L. was identical with that of T. urartu T., T. monococcum L. and T. dicoccum S.; that in D genome of Tritium aestivum L. was as same as that of Ae. squarrosa L.; that in B genome of Tritium aestivum L. differed from that of T. dicoccum S. in 0.61%. The results also suggested that A, B and D genome have the different evolution speed. PMID:11480175

  16. Identification of quantitative trait loci for abscisic acid responsiveness in the D-genome of hexaploid wheat.

    PubMed

    Iehisa, Julio C M; Matsuura, Takakazu; Mori, Izumi C; Yokota, Hirokazu; Kobayashi, Fuminori; Takumi, Shigeo

    2014-06-15

    In crop species such as wheat, abiotic stresses and preharvest sprouting reduce grain yield and quality. The plant hormone abscisic acid (ABA) plays important roles in abiotic stress tolerance and seed dormancy. In previous studies, we evaluated ABA responsiveness of 67 Aegilops tauschii accessions and their synthetic hexaploid wheat lines, finding wide variation that was due to the D-genome. In this study, quantitative trait locus (QTL) analysis was performed using an F2 population derived from crosses of highly ABA-responsive and less-responsive synthetic wheat lines. A significant QTL was detected on chromosome 6D, in a similar location to that reported for ABA responsiveness using recombinant inbred lines derived from common wheat cultivars Mironovskaya 808 and Chinese Spring. A comparative map and physiological and expression analyses of the 6D QTL suggested that this locus involved in line differences among wheat synthetics is different from that involved in cultivar differences in common wheat. The common wheat 6D QTL was found to affect seed dormancy and the regulation of cold-responsive/late embryogenesis abundant genes during dehydration. However, in synthetic wheat, we failed to detect any association of ABA responsiveness with abiotic stress tolerance or seed dormancy, at least under our experimental conditions. Development of near-isogenic lines will be important for functional analyses of the synthetic wheat 6D QTL. PMID:24877675

  17. Introgression of wheat DNA markers from A, B and D genomes in early generation progeny of Aegilops cylindrica Host x Triticum aestivum L. hybrids.

    PubMed

    Schoenenberger, N; Felber, F; Savova-Bianchi, D; Guadagnuolo, R

    2005-11-01

    Introgression from allohexaploid wheat (Triticum aestivum L., AABBDD) to allotetraploid jointed goatgrass (Aegilops cylindrica Host, CCDD) can take place in areas where the two species grow in sympatry and hybridize. Wheat and Ae. cylindrica share the D genome, issued from the common diploid ancestor Aegilops tauschii Coss. It has been proposed that the A and B genome of bread wheat are secure places to insert transgenes to avoid their introgression into Ae. cylindrica because during meiosis in pentaploid hybrids, A and B genome chromosomes form univalents and tend to be eliminated whereas recombination takes place only in D genome chromosomes. Wheat random amplified polymorphic DNA (RAPD) fragments, detected in intergeneric hybrids and introgressed to the first backcross generation with Ae. cylindrica as the recurrent parent and having a euploid Ae. cylindrica chromosome number or one supernumerary chromosome, were assigned to wheat chromosomes using Chinese Spring nulli-tetrasomic wheat lines. Introgressed fragments were not limited to the D genome of wheat, but specific fragments of A and B genomes were also present in the BC1. Their presence indicates that DNA from any of the wheat genomes can introgress into Ae. cylindrica. Successfully located RAPD fragments were then converted into highly specific and easy-to-use sequence characterised amplified regions (SCARs) through sequencing and primer design. Subsequently these markers were used to characterise introgression of wheat DNA into a BC1S1 family. Implications for risk assessment of genetically modified wheat are discussed. PMID:16133306

  18. Diversification of the Homoeologous Lr34 Sequences in Polyploid Wheat Species and Their Diploid Progenitors.

    PubMed

    Shcherban, A B; Kochieva, E Z; Salina, E A

    2016-06-01

    Allopolyploidization induces a multiple processes of genomic reorganization, including the structurally functional diversification of the homoeologous genes. An example of such diversification is the appearance of the Lr34 gene on chromosome 7D of bread wheat T. aestivum (BAD), the gene conferring durable, race non-specific protection against three fungal pathogens. In this study, we focused on the variability of a functionally critical region between exons 10-12 of Lr34 among diploid progenitors of wheat genomes and their respective polyploids. In the diploid A-genome species, two basic forms of the studied region have been revealed: (1) non-functional forms containing stop codons, or/and frameshifts (T. monococcum/T. urartu) and (2) forms with no such a mutations (T. boeoticum). The Lr34 sequence of T. urartu containing a TGA stop codon was inherited by the first tetraploid T. dicoccoides (BA), and then reorganized in some accessions of this species due to the insertion of an LTR retroelement in exon 10. Besides T. boeoticum, the second form of the Lr34 sequence is also characteristic of A. speltoides, which presumably donated this form to all polyploid descendants bearing B-genome. No differences were found between the D-genome-specific Lr34 sequences studied here and downloaded from databases, implying the highest level of conservation of the Lr34 predecessor throughout evolution. The sequence data were later used to construct phylograms, and apparent peculiarities in the evolution of the studied region of Lr34 genes discussed. PMID:27300207

  19. Introgression of stem rust resistance genes SrTA10187 and SrTA10171 from Aegilops tauschii to wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The diploid progenitor of the wheat D genome, Aegilops tauschii, has provided a wealth of genes for resistance to many diseases and insect pests of wheat. Ae. tauschii is a readily accessible pool of genes for wheat breeding as genes can be transferred to elite wheat cultivars though direct hybridi...

  20. Stably Expressed D Genome-derived HMW Glutenin Subunit Genes Transformed Into Different Durum Wheat Genotypes Change Dough Mixing Properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The glutenin subunits 1Dx5 and 1Dy10 are encoded by chromosome 1D and associated with higher dough strength in hexaploid bread wheats. In order to study the effects of their expression in different durum wheat genotypes, four cultivars commonly grown in the Mediterranean area were co-transformed, vi...

  1. Reaction of selected accessions of Aegilops tauschii to wheat blast, 2011

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The wheat pathotype of M. oryzae is not known to occur outside of South America. To prepare for possible introduction into the U.S., it is important to search for sources of resistance including resistance in relatives of wheat. Ten accessions of the D genome progenitor of wheat, Ae. tauschii, and t...

  2. Genetic map of Triticum turgidum based on a hexaploid wheat population without genetic recombination for D genome

    PubMed Central

    2012-01-01

    Background A synthetic doubled-haploid hexaploid wheat population, SynDH1, derived from the spontaneous chromosome doubling of triploid F1 hybrid plants obtained from the cross of hybrids Triticum turgidum ssp. durum line Langdon (LDN) and ssp. turgidum line AS313, with Aegilops tauschii ssp. tauschii accession AS60, was previously constructed. SynDH1 is a tetraploidization-hexaploid doubled haploid (DH) population because it contains recombinant A and B chromosomes from two different T. turgidum genotypes, while all the D chromosomes from Ae. tauschii are homogenous across the whole population. This paper reports the construction of a genetic map using this population. Results Of the 606 markers used to assemble the genetic map, 588 (97%) were assigned to linkage groups. These included 513 Diversity Arrays Technology (DArT) markers, 72 simple sequence repeat (SSR), one insertion site-based polymorphism (ISBP), and two high-molecular-weight glutenin subunit (HMW-GS) markers. These markers were assigned to the 14 chromosomes, covering 2048.79 cM, with a mean distance of 3.48 cM between adjacent markers. This map showed good coverage of the A and B genome chromosomes, apart from 3A, 5A, 6A, and 4B. Compared with previously reported maps, most shared markers showed highly consistent orders. This map was successfully used to identify five quantitative trait loci (QTL), including two for spikelet number on chromosomes 7A and 5B, two for spike length on 7A and 3B, and one for 1000-grain weight on 4B. However, differences in crossability QTL between the two T. turgidum parents may explain the segregation distortion regions on chromosomes 1A, 3B, and 6B. Conclusions A genetic map of T. turgidum including 588 markers was constructed using a synthetic doubled haploid (SynDH) hexaploid wheat population. Five QTLs for three agronomic traits were identified from this population. However, more markers are needed to increase the density and resolution of this map in the

  3. Domestication quantitative trait loci in Triticum dicoccoides, the progenitor of wheat

    PubMed Central

    Peng, Junhua; Ronin, Yefim; Fahima, Tzion; Röder, Marion S.; Li, Youchun; Nevo, Eviatar; Korol, Abraham

    2003-01-01

    Wild emmer wheat, Triticum dicoccoides, is the progenitor of modern tetraploid and hexaploid cultivated wheats. Our objective was to map domestication-related quantitative trait loci (QTL) in T. dicoccoides. The studied traits include brittle rachis, heading date, plant height, grain size, yield, and yield components. Our mapping population was derived from a cross between T. dicoccoides and Triticum durum. Approximately 70 domestication QTL effects were detected, nonrandomly distributed among and along chromosomes. Seven domestication syndrome factors were proposed, each affecting 5–11 traits. We showed: (i) clustering and strong effects of some QTLs; (ii) remarkable genomic association of strong domestication-related QTLs with gene-rich regions; and (iii) unexpected predominance of QTL effects in the A genome. The A genome of wheat may have played a more important role than the B genome during domestication evolution. The cryptic beneficial alleles at specific QTLs derived from T. dicoccoides may contribute to wheat and cereal improvement. PMID:12604784

  4. Impact of the D genome and quantitative trait loci on quantitative traits in a spring durum by spring bread wheat cross

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Desirable agronomic traits are similar for common hexaploid (6X) bread wheat (Triticum aestivum, 2n = 6x = 42, genome, AABBDD) and tetraploid (4X) durum wheat (Triticum turgidum durum, 2n = 4x = 28, genome, AABB). However, they are genetically isolated from each other due to an unequal number of ge...

  5. Diploidization and chromosomal pairing affinities in the tetraploid wheats and their putative amphiploid progenitor.

    PubMed

    Dhaliwal, H S; Johnson, B L

    1982-06-01

    The genomes of the diploid wheats Triticum boeoticum and T. urartu are closely related, giving 7II in the f1 hybrid (T(b)T(u)) and 8.4 (0-14) II + 2.5 (0-7) IV in the derived amphiploid (T(b)T(b)T(u)T(u)). The genomes of the tetraploid wheats are also closely related, giving up to 7II at the polyhaploid level (AB) in the absence of the gene Ph but 14II at the tetraploid level (AABB) in the normal presence of Ph. If the amphiploid is the progenitor of the tetraploids, one or the other homoeologue (T(b) or T(u)) in each of the 7 homoeologous groups (the 7 potential IV) must have differentiated with respect to pairing affinity in order to account for 14II in the tetraploid. Consequently, in tetraploid X amphiploid hybrids (T(b)T(u)AB) carrying the Ph gene from the tetraploid, the seven differentiated chromosomes (B) would be expected to give 7I while, on the basis of their observed chiasma frequency, T(b), T(u) and the less differentiated A would be expected to give 4.17I + 3.57II + 3.23III), assuming homoeologous pairing. The expected chromosomal configuration freqencies at MI (11.17I + 3.57II + 3.23III) closely fit the observed values (11.22I + 3.45II + 3.19III + 0.071IV) for such hybrids (X(2) = 0.0046; P>0.99). Thus diploidization of the boeoticum-urartu amphiploid clearly could account for the origin of the tetraploid wheats. Furthermore, T. aestivum X amphiploid hybrids (T(b)T(u)ABD) with and without Ph indicated that B as well as A chomosomes tended to pair with their presumed T(b)T(u) homologues in the absence of Ph. Other tests showed that the tetraploid wheats could not plausibly have originated from any postulated Triticum-Sitopsis (TTSS) parental combinations with or without such chromosomal differentiation. PMID:24270332

  6. Map-based analysis of the tenacious glume gene Tg-B1 of wild emmer and its role in wheat domestication

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The domestication of wheat was instrumental in spawning the civilization of humankind, and it occurred through genetic mutations that gave rise to types with non-fragile rachises, soft glumes, and free-threshing seed. The Tg-D1 gene on chromosome 2D of Aegilops tauschii, the D-genome progenitor of ...

  7. Physical mapping resources for large plant genomes: radiation hybrids for wheat D-genome progenitor aegilops tauschii accession AL8/78

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: A high quality reference sequence can provide a complete catalog of genes of a species, the regulatory elements that control their structure and function provide the basis for understanding the role of genes in evolution and development. However, development of a high quality referenc...

  8. THE EFFECT OF D-GENOME SUBSTITUTIONS ON AGRONOMIC PERFORMANCE AND END-USE QUALITY OF 'PRESTO' TRITICALE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hexaploid triticale (2n = 6x = 42, AABBRR) and wheat (2n = 6x = 42, AABBDD) differ in their R and D genomes. An unanswered question is whether introgressions of the D-genome chromatin could improve triticale. For example, in hexaploid wheat, the endosperm storage proteins, which determine bread-maki...

  9. Genome Variation Within Triticale in Comparison to its Wheat and Rye Progenitors

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genome variation in the intergeneric wheat-rye hybrid triticale (X Triticosecale Wittmack) has been a puzzle to scientists and plant breeders since the first triticale was synthesized. The existence of unexplained genetic variation in triticale as compared to the parents has been a hindrance to bre...

  10. Prevalence of gene expression additivity in genetically stable wheat allohexaploids.

    PubMed

    Chelaifa, Houda; Chagué, Véronique; Chalabi, Smahane; Mestiri, Imen; Arnaud, Dominique; Deffains, Denise; Lu, Yunhai; Belcram, Harry; Huteau, Virginie; Chiquet, Julien; Coriton, Olivier; Just, Jérémy; Jahier, Joseph; Chalhoub, Boulos

    2013-02-01

    The reprogramming of gene expression appears as the major trend in synthetic and natural allopolyploids where expression of an important proportion of genes was shown to deviate from that of the parents or the average of the parents. In this study, we analyzed gene expression changes in previously reported, highly stable synthetic wheat allohexaploids that combine the D genome of Aegilops tauschii and the AB genome extracted from the natural hexaploid wheat Triticum aestivum. A comprehensive genome-wide analysis of transcriptional changes using the Affymetrix GeneChip Wheat Genome Array was conducted. Prevalence of gene expression additivity was observed where expression does not deviate from the average of the parents for 99.3% of 34,820 expressed transcripts. Moreover, nearly similar expression was observed (for 99.5% of genes) when comparing these synthetic and natural wheat allohexaploids. Such near-complete additivity has never been reported for other allopolyploids and, more interestingly, for other synthetic wheat allohexaploids that differ from the ones studied here by having the natural tetraploid Triticum turgidum as the AB genome progenitor. Our study gave insights into the dynamics of additive gene expression in the highly stable wheat allohexaploids. PMID:23278496

  11. Recent emergence of the wheat Lr34 multi-pathogen resistance: insights from haplotype analysis in wheat, rice, sorghum and Aegilops tauschii.

    PubMed

    Krattinger, Simon G; Jordan, David R; Mace, Emma S; Raghavan, Chitra; Luo, Ming-Cheng; Keller, Beat; Lagudah, Evans S

    2013-03-01

    Spontaneous sequence changes and the selection of beneficial mutations are driving forces of gene diversification and key factors of evolution. In highly dynamic co-evolutionary processes such as plant-pathogen interactions, the plant's ability to rapidly adapt to newly emerging pathogens is paramount. The hexaploid wheat gene Lr34, which encodes an ATP-binding cassette (ABC) transporter, confers durable field resistance against four fungal diseases. Despite its extensive use in breeding and agriculture, no increase in virulence towards Lr34 has been described over the last century. The wheat genepool contains two predominant Lr34 alleles of which only one confers disease resistance. The two alleles, located on chromosome 7DS, differ by only two exon-polymorphisms. Putatively functional homoeologs and orthologs of Lr34 are found on the B-genome of wheat and in rice and sorghum, but not in maize, barley and Brachypodium. In this study we present a detailed haplotype analysis of homoeologous and orthologous Lr34 genes in genetically and geographically diverse selections of wheat, rice and sorghum accessions. We found that the resistant Lr34 haplotype is unique to the wheat D-genome and is not found in the B-genome of wheat or in rice and sorghum. Furthermore, we only found the susceptible Lr34 allele in a set of 252 Ae. tauschii genotypes, the progenitor of the wheat D-genome. These data provide compelling evidence that the Lr34 multi-pathogen resistance is the result of recent gene diversification occurring after the formation of hexaploid wheat about 8,000 years ago. PMID:23117720

  12. [Phylogenetic relationships and intraspecific variation of D-genome Aegilops L. as revealed by RAPD analysis].

    PubMed

    Goriunova, S V; Kochieva, E Z; Chikida, N N; Pukhal'skiĭ, V A

    2004-05-01

    RAPD analysis was carried out to study the genetic variation and phylogenetic relationships of polyploid Aegilops species, which contain the D genome as a component of the alloploid genome, and diploid Aegilops tauschii, which is a putative donor of the D genome for common wheat. In total, 74 accessions of six D-genome Aegilops species were examined. The highest intraspecific variation (0.03-0.21) was observed for Ae. tauschii. Intraspecific distances between accessions ranged 0.007-0.067 in Ae. cylindrica, 0.017-0.047 in Ae. vavilovii, and 0.00-0.053 in Ae. juvenalis. Likewise, Ae. ventricosa and Ae. crassa showed low intraspecific polymorphism. The among-accession difference in alloploid Ae. ventricosa (genome DvNv) was similar to that of one parental species, Ae. uniaristata (N), and substantially lower than in the other parent, Ae. tauschii (D). The among-accession difference in Ae. cylindrica (CcDc) was considerably lower than in either parent, Ae. tauschii (D) or Ae. caudata (C). With the exception of Ae. cylindrica, all D-genome species--Ae. tauschii (D), Ae. ventricosa (DvNv), Ae. crassa (XcrDcrl and XcrDcrlDcr2), Ae. juvenalis (XjDjUj), and Ae. vavilovii (XvaDvaSva)--formed a single polymorphic cluster, which was distinct from clusters of other species. The only exception, Ae. cylindrica, did not group with the other D-genome species, but clustered with Ae. caudata (C), a donor of the C genome. The cluster of these two species was clearly distinct from the cluster of the other D-genome species and close to a cluster of Ae. umbellulata (genome U) and Ae. ovata (genome UgMg). Thus, RAPD analysis for the first time was used to estimate and to compare the interpopulation polymorphism and to establish the phylogenetic relationships of all diploid and alloploid D-genome Aegilops species. PMID:15272562

  13. Duplication and partitioning in evolution and function of homoeologous Q loci governing domestication characters in polyploid wheat

    PubMed Central

    Zhang, Zengcui; Belcram, Harry; Gornicki, Piotr; Charles, Mathieu; Just, Jérémy; Huneau, Cécile; Magdelenat, Ghislaine; Couloux, Arnaud; Samain, Sylvie; Gill, Bikram S.; Rasmussen, Jack B.; Barbe, Valérie; Faris, Justin D.; Chalhoub, Boulos

    2011-01-01

    The Q gene encodes an AP2-like transcription factor that played an important role in domestication of polyploid wheat. The chromosome 5A Q alleles (5AQ and 5Aq) have been well studied, but much less is known about the q alleles on wheat homoeologous chromosomes 5B (5Bq) and 5D (5Dq). We investigated the organization, evolution, and function of the Q/q homoeoalleles in hexaploid wheat (Triticum aestivum L.). Q/q gene sequences are highly conserved within and among the A, B, and D genomes of hexaploid wheat, the A and B genomes of tetraploid wheat, and the A, S, and D genomes of the diploid progenitors, but the intergenic regions of the Q/q locus are highly divergent among homoeologous genomes. Duplication of the q gene 5.8 Mya was likely followed by selective loss of one of the copies from the A genome progenitor and the other copy from the B, D, and S genomes. A recent V329-to-I mutation in the A lineage is correlated with the Q phenotype. The 5Bq homoeoalleles became a pseudogene after allotetraploidization. Expression analysis indicated that the homoeoalleles are coregulated in a complex manner. Combined phenotypic and expression analysis indicated that, whereas 5AQ plays a major role in conferring domestication-related traits, 5Dq contributes directly and 5Bq indirectly to suppression of the speltoid phenotype. The evolution of the Q/q loci in polyploid wheat resulted in the hyperfunctionalization of 5AQ, pseudogenization of 5Bq, and subfunctionalization of 5Dq, all contributing to the domestication traits. PMID:22042872

  14. Wheat - Aegilops introgressions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aegilops is the most closely related genus to Triticum in the tribe Triticeae. Aegilops speltoides Tausch (B genome donor) and Ae. tauschii Coss. (D genome donor) contributed two of the three genomes present in common wheat (Triticum aestivum L., 2n = 6x = 42, AABBDD genomes). The Aegilops genus c...

  15. Genes encoding plastid acetyl-CoA carboxylase and 3-phosphoglycerate kinase of the Triticum/Aegilops complex and the evolutionary history of polyploid wheat.

    PubMed

    Huang, Shaoxing; Sirikhachornkit, Anchalee; Su, Xiujuan; Faris, Justin; Gill, Bikram; Haselkorn, Robert; Gornicki, Piotr

    2002-06-11

    The classic wheat evolutionary history is one of adaptive radiation of the diploid Triticum/Aegilops species (A, S, D), genome convergence and divergence of the tetraploid (Triticum turgidum AABB, and Triticum timopheevii AAGG) and hexaploid (Triticum aestivum, AABBDD) species. We analyzed Acc-1 (plastid acetyl-CoA carboxylase) and Pgk-1 (plastid 3-phosphoglycerate kinase) genes to determine phylogenetic relationships among Triticum and Aegilops species of the wheat lineage and to establish the timeline of wheat evolution based on gene sequence comparisons. Triticum urartu was confirmed as the A genome donor of tetraploid and hexaploid wheat. The A genome of polyploid wheat diverged from T. urartu less than half a million years ago (MYA), indicating a relatively recent origin of polyploid wheat. The D genome sequences of T. aestivum and Aegilops tauschii are identical, confirming that T. aestivum arose from hybridization of T. turgidum and Ae. tauschii only 8,000 years ago. The diploid Triticum and Aegilops progenitors of the A, B, D, G, and S genomes all radiated 2.5-4.5 MYA. Our data suggest that the Acc-1 and Pgk-1 loci have different histories in different lineages, indicating genome mosaicity and significant intraspecific differentiation. Some loci of the S genome of Aegilops speltoides and the G genome of T. timophevii are closely related, suggesting the same origin of some parts of their genomes. None of the Aegilops genomes analyzed is a close relative of the B genome, so the diploid progenitor of the B genome remains unknown. PMID:12060759

  16. Molecular evolution of Wcor15 gene enhanced our understanding of the origin of A, B and D genomes in Triticum aestivum.

    PubMed

    Liu, Fangfang; Si, Hongqi; Wang, Chengcheng; Sun, Genlou; Zhou, Erting; Chen, Can; Ma, Chuanxi

    2016-01-01

    The allohexaploid bread wheat originally derived from three closely related species with A, B and D genome. Although numerous studies were performed to elucidate its origin and phylogeny, no consensus conclusion has reached. In this study, we cloned and sequenced the genes Wcor15-2A, Wcor15-2B and Wcor15-2D in 23 diploid, 10 tetraploid and 106 hexaploid wheat varieties and analyzed their molecular evolution to reveal the origin of the A, B and D genome in Triticum aestivum. Comparative analyses of sequences in diploid, tetraploid and hexaploid wheats suggest that T. urartu, Ae. speltoides and Ae. tauschii subsp. strangulata are most likely the donors of the Wcor15-2A, Wcor15-2B and Wcor15-2D locus in common wheat, respectively. The Wcor15 genes from subgenomes A and D were very conservative without insertion and deletion of bases during evolution of diploid, tetraploid and hexaploid. Non-coding region of Wcor15-2B gene from B genome might mutate during the first polyploidization from Ae. speltoides to tetraploid wheat, however, no change has occurred for this gene during the second allopolyploidization from tetraploid to hexaploid. Comparison of the Wcor15 gene shed light on understanding of the origin of the A, B and D genome of common wheat. PMID:27526862

  17. Molecular evolution of Wcor15 gene enhanced our understanding of the origin of A, B and D genomes in Triticum aestivum

    PubMed Central

    Liu, Fangfang; Si, Hongqi; Wang, Chengcheng; Sun, Genlou; Zhou, Erting; Chen, Can; Ma, Chuanxi

    2016-01-01

    The allohexaploid bread wheat originally derived from three closely related species with A, B and D genome. Although numerous studies were performed to elucidate its origin and phylogeny, no consensus conclusion has reached. In this study, we cloned and sequenced the genes Wcor15-2A, Wcor15-2B and Wcor15-2D in 23 diploid, 10 tetraploid and 106 hexaploid wheat varieties and analyzed their molecular evolution to reveal the origin of the A, B and D genome in Triticum aestivum. Comparative analyses of sequences in diploid, tetraploid and hexaploid wheats suggest that T. urartu, Ae. speltoides and Ae. tauschii subsp. strangulata are most likely the donors of the Wcor15-2A, Wcor15-2B and Wcor15-2D locus in common wheat, respectively. The Wcor15 genes from subgenomes A and D were very conservative without insertion and deletion of bases during evolution of diploid, tetraploid and hexaploid. Non-coding region of Wcor15-2B gene from B genome might mutate during the first polyploidization from Ae. speltoides to tetraploid wheat, however, no change has occurred for this gene during the second allopolyploidization from tetraploid to hexaploid. Comparison of the Wcor15 gene shed light on understanding of the origin of the A, B and D genome of common wheat. PMID:27526862

  18. Identification of transposons, retroelements, and a gene family predominantly expressed in floral tissues in chromosome 3DS of the hexaploid wheat progenitor Aegilops tauschii.

    PubMed

    Whitford, Ryan; Baumann, Ute; Sutton, Tim; Gumaelius, Luke; Wolters, Petra; Tingey, Scott; Able, Jason A; Langridge, Peter

    2007-01-01

    A multigene family expressed during early floral development was identified on the short arm of wheat chromosome 3D in the region of the Ph2 locus, a locus controlling homoeologous chromosome pairing in allohexaploid wheat. Physical, genetic and molecular characterisation of the Wheat Meiosis 1 (WM1) gene family identified seven members that localised within a region of 173-kb. WM1 gene family members were sequenced and they encode mainly type Ia plasma membrane-anchored leucine rich repeat-like receptor proteins. In situ expression profiling suggests the gene family is predominantly expressed in floral tissue. In addition to the WM1 gene family, a number of other genes, gene fragments and pseudogenes were identified. It has been predicted that there is approximately one gene every 19-kb and that this region of the wheat genome contains 23 repetitive elements including BARE-1 and Wis2-1 like sequences. Nearly 50% of the repetitive elements identified were similar to known transposons from the CACTA superfamily. Ty1-copia, Ty3-gypsy and Athila LTR retroelements were also prevalent within the region. The WM1 gene cluster is present on 3DS and on barley 3HS but missing from the A and B genomes of hexaploid wheat. This suggests either recent generation of the cluster or specific deletion of the cluster during wheat polyploidisation. The evolutionary significance of the cluster, its possible roles in disease response or floral and early meiotic development and its location at or near the Ph2 locus are discussed. PMID:16534632

  19. [Development of Triticale and soft wheat forms with substituted wheat and rye chromosomes].

    PubMed

    Suvorova, E Iu; Cherednichenko, V N; Semenov, V I

    2000-01-01

    During hybridization between winter forms of hexaploid (6x) triticale and soft wheat varieties the intergenomic substitution of alian chromosomes occurs. As a result of these crosses the forms of 6x-triticale with D(R)-substitution of chromosomes in R-rye genome by wheat ones of D-genome and wheat revertants with rye chromosomes replacing the wheat ones are originated. This is the simplest and the most effective technique for developing of selected lines of triticale and soft wheat with alien substituted chromosomes and valuable genes transfer. PMID:11213630

  20. Hulled wheats: Origin, nutritional value and future prospects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wild and domesticated hulled (or non-free threshing) wheat species are among the most ancient cereals of the Fertile Crescent and the Mediterranean Region. They include wild emmer, the progenitor of most cultivated wheat species; wild and domesticated einkorn; and domesticated emmer and spelt wheat....

  1. The 3D Genome as Moderator of Chromosomal Communication.

    PubMed

    Dekker, Job; Mirny, Leonid

    2016-03-10

    Proper expression of genes requires communication with their regulatory elements that can be located elsewhere along the chromosome. The physics of chromatin fibers imposes a range of constraints on such communication. The molecular and biophysical mechanisms by which chromosomal communication is established, or prevented, have become a topic of intense study, and important roles for the spatial organization of chromosomes are being discovered. Here we present a view of the interphase 3D genome characterized by extensive physical compartmentalization and insulation on the one hand and facilitated long-range interactions on the other. We propose the existence of topological machines dedicated to set up and to exploit a 3D genome organization to both promote and censor communication along and between chromosomes. PMID:26967279

  2. Phylogeny and expression of paralogous and orthologous sulphate transporter genes in diploid and hexaploid wheats.

    PubMed

    Buchner, Peter; Prosser, Ian M; Hawkesford, Malcolm J

    2004-06-01

    Twelve genes encoding two closely related subtypes (ST1.1a and ST1.1b) of a sulphate transporter have been identified in the diploid wheats Aegilops tauschii, Triticum urartu, and Aegilops speltoides, as well as the hexaploid Triticum aestivum. Based on phylogenetic comparisons with other plant sulphate transporters, the ST1.1a and 1.1b subtypes aligned with group 1 of the plant sulphate transporter gene family. The exon-intron structure was conserved within the ST1.1a or ST1.1b genes; however, substantial variability in intron sequences existed between the two types. The high overall sequence similarity indicated that ST1.1b represented a duplication of the ST1.1a gene, which must have occurred before the evolution of the ancestral diploid wheat progenitor. In contrast with the close relationship of the T. urartu and Ae. tauschii sequences to the corresponding A and D genome sequences of T. aestivum, the divergence between the Ae. speltoides sequences and the B genome sequences suggested that the B genome ST1.1a gene has been modified by recombination. Transcript analysis revealed predominant expression of the ST1.1a type and an influence of sulphur availability on the level of expression. PMID:15190370

  3. Progenitor Epithelium

    PubMed Central

    Marty-Santos, Leilani

    2015-01-01

    Insulin-producing β cells within the vertebrate fetal pancreas acquire their fate in a step-wise manner. Whereas the intrinsic factors dictating the transcriptional or epigenetic status of pancreatic lineages have been intensely examined, less is known about cell–cell interactions that might constitute a niche for the developing β cell lineage. It is becoming increasingly clear that understanding and recapitulating these steps may instruct in vitro differentiation of embryonic stem cells and/or therapeutic regeneration. Indeed, directed differentiation techniques have improved since transitioning from 2D to 3D cultures, suggesting that the 3D microenvironment in which β cells are born is critical. However, to date, it remains unknown whether the changing architecture of the pancreatic epithelium impacts the fate of cells therein. An emerging challenge in the field is to elucidate how progenitors are allocated during key events, such as the stratification and subsequent resolution of the pre-pancreatic epithelium, as well as the formation of lumens and branches. Here, we assess the progenitor epithelium and examine how it might influence the emergence of pancreatic multipotent progenitors (MPCs), which give rise to β cells and other pancreatic lineages. PMID:26216134

  4. Synthetic hexaploids: Harnessing species of the primary gene pool for wheat improvement

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Incorporation of genetic diversity into elite wheat cultivars has long been recognized as a means of improving wheat productivity and securing the global wheat supply. Synthetic hexaploid wheat (SHW) recreated from its two progenitor species, the tetraploid, Triticum turgidum and its diploid wild r...

  5. Evolution of New Disease Specificity at a Single Resistance Locus in a Crop-Weed Complex: Reconstitution of the Lr21 Gene in Wheat.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leaf-rust resistance gene Lr21, present in modern varieties of hexaploid wheat, originated in goatgrass Aegilops tauschii Coss., the D genome donor of wheat. The goatgrass donor was collected in Iran where it grows as a weed in wheat fields as part of the native agricultural ecosystem. In order to ...

  6. Genetic diversity among synthetic hexaploid wheat accessions with resistance to several fungal diseases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Synthetic hexaploid wheat (SHW) is known to be an excellent vehicle for transferring large genetic variations especially the many useful traits present in the D genome of Aegilops tauschii Coss (2n=2x=14, DD) for improvement of cultivated wheat (Triticum aestivum L., 2n=6x=42, AABBDD). The objectiv...

  7. Genetic diversity in conventional and synthetic wheats with drought and salinity tolerance based on AFLP

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetic diversity, among fourteen drought and twenty-seven salinity tolerant conventional and synthetic wheat (Triticum sp.) accessions containing different sources of the D genome, was assessed using amplified fragment length polymorphism (AFLP). The wheat accessions were analyzed with 20 EcoRI/Mse...

  8. Identification and mapping of QTLs for FHB resistance in a synthetic hexaploid wheat line

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The synthetic hexaploid wheat (SHW) lines derived from crosses between tetraploid wheat (AABB genome) and Aegilops tauschii (D genome) possess resistance to various diseases including Fusarium head blight (FHB). However, the genetics of FHB resistance in these synthetic lines is poorly understood. B...

  9. RFLP-based analysis of three RbcS subfamilies in diploid and polyploid species of wheat.

    PubMed

    Galili, S; Avivi, Y; Millet, E; Feldman, M

    2000-05-01

    The RbcS multigene family of hexaploid (bread) wheat, Triticum aestivum (genome BBAADD), which encodes the small subunit of Rubisco, comprises at least 22 genes. Based on their 3' non-coding sequences, these genes have been classified into four subfamilies (SFs), of which three (SF-2, SF-3 and SF-4) are located on chromosomes of homoeologous group 2 and one (SF-1) on homoeologous group 5. In the present study we hybridized three RbcS subfamily-specific probes (for SF-1, SF-2 and SF-3) to total DNA digested with four restriction enzymes and analyzed the RFLP patterns of these subfamilies in eight diploid species of Aegilops and Triticum, and in two tetraploid and one hexaploid species of wheat (the diploid species are the putative progenitors of the polyploid wheats). The three subfamilies varied in their level of polymorphism, with SF-2 being the most polymorphic in all species. In the diploids, the order of polymorphism was SF-2 > SF-3 > SF-1, and in the polyploids SF-2 > SF-1 > SF-3. The RbcS genes of the conserved SF-1 were previously reported to have the highest expression levels in all the wheat tissues studied, indicating a negative correlation between polymorphism and gene expression. Among the diploids, the species with the D and the S genomes were the most polymorphic and the A-genome species were the least polymorphic. The polyploids were less polymorphic than the diploids. Within the polyploids, the A genome was somewhat more polymorphic than the B genome, while the D genome was the most conserved. Among the diploid species with the A genome, the RFLP pattern of T. urartu was closer to that of the A genome of the common wheat cultivar Chinese Spring (CS) than to that of T. monococcum. The pattern in Ae. tauschii was similar to that of the D genome of CS. Only partial resemblance was found between the RFLP patterns of the species with the S genome and the B genome of CS. PMID:10852490

  10. Ecogeography, genetic diversity, and breeding value of wild emmer wheat (Triticum dicoccoides Korn ex Asch. & Graebn.) Thell.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wild emmer wheat (Triticum dicoccoides Körn ex Asch. & Graebn.) Thell. is the allotetraploid (2n=4x=28; genome BBAA) progenitor of cultivated wheat. It is fully compatible with the tetraploid (BBAA) durum wheat (Triticum durum), and can be crossed with the hexaploid (2n=6x=42; BBAADD) wheat (Triticu...

  11. Two Homoeologous Wheat Genes Confer Sensitivity to a Single Host-Selective Toxin and Susceptibility to Stagonospora nodorum blotch (SNB)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The pathogen Stagonospora nodorum produces multiple host-selective toxins that interact with corresponding wheat sensitivity genes in an inverse gene-for-gene manner to cause the disease Stagonospora nodorum blotch (SNB) in wheat. Here, we screened accessions of Aegilops tauschii, the D-genome donor...

  12. Development of a D genome specific marker resource for diploid and hexaploid wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mapping and map-based cloning of genes that control agriculturally and economically important traits remain great challenges for plants with complex highly repetitive genomes such as those of the grass tribe, Triticeae. Mapping limitations in the Triticeae are primarily due to low frequencies of po...

  13. Quantification of genetic relationships among A genomes of wheats.

    PubMed

    Brandolini, A; Vaccino, P; Boggini, G; Ozkan, H; Kilian, B; Salamini, F

    2006-04-01

    The genetic relationships of A genomes of Triticum urartu (Au) and Triticum monococcum (Am) in polyploid wheats are explored and quantified by AFLP fingerprinting. Forty-one accessions of A-genome diploid wheats, 3 of AG-genome wheats, 19 of AB-genome wheats, 15 of ABD-genome wheats, and 1 of the D-genome donor Ae. tauschii have been analysed. Based on 7 AFLP primer combinations, 423 bands were identified as potentially A genome specific. The bands were reduced to 239 by eliminating those present in autoradiograms of Ae. tauschii, bands interpreted as common to all wheat genomes. Neighbour-joining analysis separates T. urartu from T. monococcum. Triticum urartu has the closest relationship to polyploid wheats. Triticum turgidum subsp. dicoccum and T. turgidum subsp. durum lines are included in tightly linked clusters. The hexaploid spelts occupy positions in the phylogenetic tree intermediate between bread wheats and T. turgidum. The AG-genome accessions cluster in a position quite distant from both diploid and other polyploid wheats. The estimates of similarity between A genomes of diploid and polyploid wheats indicate that, compared with Am, Au has around 20% higher similarity to the genomes of polyploid wheats. Triticum timo pheevii AG genome is molecularly equidistant from those of Au and Am wheats. PMID:16699549

  14. De Novo Transcriptome Assembly and Analyses of Gene Expression during Photomorphogenesis in Diploid Wheat Triticum monococcum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Triticum monococcum (2n), a close ancestor of the A-genome progenitor of cultivated hexaploid wheat, was used as a model to study components regulating photomorphogenesis in diploid wheat. Constructed were genome-wide transcriptomes of two Triticum monococcum subspecies, the wild winter wheat T. mo...

  15. A New Class of Wheat Gliadin Genes and Proteins

    PubMed Central

    Anderson, Olin D.; Dong, Lingli; Huo, Naxin; Gu, Yong Q.

    2012-01-01

    The utility of mining DNA sequence data to understand the structure and expression of cereal prolamin genes is demonstrated by the identification of a new class of wheat prolamins. This previously unrecognized wheat prolamin class, given the name δ-gliadins, is the most direct ortholog of barley γ3-hordeins. Phylogenetic analysis shows that the orthologous δ-gliadins and γ3-hordeins form a distinct prolamin branch that existed separate from the γ-gliadins and γ-hordeins in an ancestral Triticeae prior to the branching of wheat and barley. The expressed δ-gliadins are encoded by a single gene in each of the hexaploid wheat genomes. This single δ-gliadin/γ3-hordein ortholog may be a general feature of the Triticeae tribe since examination of ESTs from three barley cultivars also confirms a single γ3-hordein gene. Analysis of ESTs and cDNAs shows that the genes are expressed in at least five hexaploid wheat cultivars in addition to diploids Triticum monococcum and Aegilops tauschii. The latter two sequences also allow assignment of the δ-gliadin genes to the A and D genomes, respectively, with the third sequence type assumed to be from the B genome. Two wheat cultivars for which there are sufficient ESTs show different patterns of expression, i.e., with cv Chinese Spring expressing the genes from the A and B genomes, while cv Recital has ESTs from the A and D genomes. Genomic sequences of Chinese Spring show that the D genome gene is inactivated by tandem premature stop codons. A fourth δ-gliadin sequence occurs in the D genome of both Chinese Spring and Ae. tauschii, but no ESTs match this sequence and limited genomic sequences indicates a pseudogene containing frame shifts and premature stop codons. Sequencing of BACs covering a 3 Mb region from Ae. tauschii locates the δ-gliadin gene to the complex Gli-1 plus Glu-3 region on chromosome 1. PMID:23284903

  16. A new class of wheat gliadin genes and proteins.

    PubMed

    Anderson, Olin D; Dong, Lingli; Huo, Naxin; Gu, Yong Q

    2012-01-01

    The utility of mining DNA sequence data to understand the structure and expression of cereal prolamin genes is demonstrated by the identification of a new class of wheat prolamins. This previously unrecognized wheat prolamin class, given the name δ-gliadins, is the most direct ortholog of barley γ3-hordeins. Phylogenetic analysis shows that the orthologous δ-gliadins and γ3-hordeins form a distinct prolamin branch that existed separate from the γ-gliadins and γ-hordeins in an ancestral Triticeae prior to the branching of wheat and barley. The expressed δ-gliadins are encoded by a single gene in each of the hexaploid wheat genomes. This single δ-gliadin/γ3-hordein ortholog may be a general feature of the Triticeae tribe since examination of ESTs from three barley cultivars also confirms a single γ3-hordein gene. Analysis of ESTs and cDNAs shows that the genes are expressed in at least five hexaploid wheat cultivars in addition to diploids Triticum monococcum and Aegilops tauschii. The latter two sequences also allow assignment of the δ-gliadin genes to the A and D genomes, respectively, with the third sequence type assumed to be from the B genome. Two wheat cultivars for which there are sufficient ESTs show different patterns of expression, i.e., with cv Chinese Spring expressing the genes from the A and B genomes, while cv Recital has ESTs from the A and D genomes. Genomic sequences of Chinese Spring show that the D genome gene is inactivated by tandem premature stop codons. A fourth δ-gliadin sequence occurs in the D genome of both Chinese Spring and Ae. tauschii, but no ESTs match this sequence and limited genomic sequences indicates a pseudogene containing frame shifts and premature stop codons. Sequencing of BACs covering a 3 Mb region from Ae. tauschii locates the δ-gliadin gene to the complex Gli-1 plus Glu-3 region on chromosome 1. PMID:23284903

  17. Improving 3D Genome Reconstructions Using Orthologous and Functional Constraints

    PubMed Central

    Diament, Alon; Tuller, Tamir

    2015-01-01

    The study of the 3D architecture of chromosomes has been advancing rapidly in recent years. While a number of methods for 3D reconstruction of genomic models based on Hi-C data were proposed, most of the analyses in the field have been performed on different 3D representation forms (such as graphs). Here, we reproduce most of the previous results on the 3D genomic organization of the eukaryote Saccharomyces cerevisiae using analysis of 3D reconstructions. We show that many of these results can be reproduced in sparse reconstructions, generated from a small fraction of the experimental data (5% of the data), and study the properties of such models. Finally, we propose for the first time a novel approach for improving the accuracy of 3D reconstructions by introducing additional predicted physical interactions to the model, based on orthologous interactions in an evolutionary-related organism and based on predicted functional interactions between genes. We demonstrate that this approach indeed leads to the reconstruction of improved models. PMID:26000633

  18. From genome to gene: a new epoch for wheat research?

    PubMed

    Wang, Meng; Wang, Shubin; Xia, Guangmin

    2015-06-01

    Genetic research for bread wheat (Triticum aestivum), a staple crop around the world, has been impeded by its complex large hexaploid genome that contains a high proportion of repetitive DNA. Recent advances in sequencing technology have now overcome these challenges and led to genome drafts for bread wheat and its progenitors as well as high-resolution transcriptomes. However, the exploitation of these data for identifying agronomically important genes in wheat is lagging behind. We review recent wheat genome sequencing achievements and focus on four aspects of strategies and future hotspots for wheat improvement: positional cloning, 'omics approaches, combining forward and reverse genetics, and epigenetics. PMID:25887708

  19. Physical mapping of a large plant genome using global high-information content fingerprinting: a distal region of wheat chromosome 3DS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Physical maps employing libraries of bacterial artificial chromosome (BAC) clones are essential for comparative genomics and sequencing of large and repetitive genomes such as those of wheat. We report the use of the Ae. tauschii, the diploid ancestor of the wheat D genome, for the construction of t...

  20. Simultaneous transfer, introgression and genomic localization of genes for resistance to stem rust race TTKSK Ug99 from Aegilops tauschii to wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat production is currently threatened by widely virulent races of the wheat stem rust fungus, Puccinia graminis f. sp. tritici, that are part of the TTKSK (also known as ‘Ug99’) race group. The diploid D genome donor species Aegilops tauschii (2n=2x=14, DD) is a readily accessible source of resis...

  1. Structure and dynamics of retrotransposons at wheat centromeres and pericentromeres.

    PubMed

    Liu, Zhao; Yue, Wei; Li, Dayong; Wang, Richard R-C; Kong, Xiuying; Lu, Kun; Wang, Guixiang; Dong, Yushen; Jin, Weiwei; Zhang, Xueyong

    2008-10-01

    Little is known of the dynamics of centromeric DNA in polyploid plants. We report the sequences of two centromere-associated bacterial artificial chromosome clones from a Triticum boeoticum library. Both autonomous and non-autonomous wheat centromeric retrotransposons (CRWs) were identified, both being closely associated with the centromeres of wheat. Fiber-fluorescence in situ hybridization and chromatin immunoprecipitation analysis showed that wheat centromeric retrotransposons (CRWs) represent a dominant component of the wheat centromere and are associated with centromere function. CRW copy number showed variation among different genomes: the D genome chromosomes contained fewer copies than either the A or B genome chromosomes. The frequency of lengthy continuous CRW arrays was higher than that in either rice or maize. The dynamics of CRWs and other retrotransposons at centromeric and pericentromeric regions during diploid speciation and polyploidization of wheat and its related species are discussed. PMID:18496705

  2. Making the Bread: Insights from Newly Synthesized Allohexaploid Wheat.

    PubMed

    Li, Ai-li; Geng, Shuai-Feng; Zhang, Lian-quan; Liu, Deng-cai; Mao, Long

    2015-06-01

    Bread wheat (or common wheat, Triticum aestivum) is an allohexaploid (AABBDD, 2n = 6x = 42) that arose by hybridization between a cultivated tetraploid wheat T. turgidum (AABB, 2n = 4x = 28) and the wild goatgrass Aegilops tauschii (DD, 2n = 2x = 14). Polyploidization provided niches for rigorous genome modification at cytogenetic, genetic, and epigenetic levels, rendering a broader spread than its progenitors. This review summarizes the latest advances in understanding gene regulation mechanisms in newly synthesized allohexaploid wheat and possible correlation with polyploid growth vigor and adaptation. Cytogenetic studies reveal persistent association of whole-chromosome aneuploidy with nascent allopolyploids, in contrast to the genetic stability in common wheat. Transcriptome analysis of the euploid wheat shows that small RNAs are driving forces for homoeo-allele expression regulation via genetic and epigenetic mechanisms. The ensuing non-additively expressed genes and those with expression level dominance to the respective progenitor may play distinct functions in growth vigor and adaptation in nascent allohexaploid wheat. Further genetic diploidization of allohexaploid wheat is not random. Regional asymmetrical gene distribution, rather than subgenome dominance, is observed in both synthetic and natural allohexaploid wheats. The combinatorial effects of diverged genomes, subsequent selection of specific gene categories, and subgenome-specific traits are essential for the successful establishment of common wheat. PMID:25747845

  3. Genetic Variation of Seed Dormancy in Synthetic Hexaploid Wheat-Derived Populations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aegilops tauschii, the D-genome donor of wheat (Triticum aestivum), has very strong seed dormancy and genes controlling the trait may be used in breeding programs to manipulate germinability of improved cultivars. Thus, this research was conducted to initiate a project to identify dormancy genes fro...

  4. Analysis of the Lr34/Yr18 rust resistance region in wheat germplasm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An insertion/deletion size variant located at the csLV34 locus on chromosome 7D within an intron sequence of a sulphate transporter-like gene tightly linked to the Lr34/Yr18 dual rust resistance was used to examine a global collection of wheat cultivars, landraces and D genome containing diploid and...

  5. Ancient hybridizations among the ancestral genomes of bread wheat.

    PubMed

    Marcussen, Thomas; Sandve, Simen R; Heier, Lise; Spannagl, Manuel; Pfeifer, Matthias; Jakobsen, Kjetill S; Wulff, Brande B H; Steuernagel, Burkhard; Mayer, Klaus F X; Olsen, Odd-Arne

    2014-07-18

    The allohexaploid bread wheat genome consists of three closely related subgenomes (A, B, and D), but a clear understanding of their phylogenetic history has been lacking. We used genome assemblies of bread wheat and five diploid relatives to analyze genome-wide samples of gene trees, as well as to estimate evolutionary relatedness and divergence times. We show that the A and B genomes diverged from a common ancestor ~7 million years ago and that these genomes gave rise to the D genome through homoploid hybrid speciation 1 to 2 million years later. Our findings imply that the present-day bread wheat genome is a product of multiple rounds of hybrid speciation (homoploid and polyploid) and lay the foundation for a new framework for understanding the wheat genome as a multilevel phylogenetic mosaic. PMID:25035499

  6. Eat Wheat!

    ERIC Educational Resources Information Center

    Idaho Wheat Commission, Boise.

    This pamphlet contains puzzles, games, and a recipe designed to teach elementary school pupils about wheat. It includes word games based on the U.S. Department of Agriculture Food Guide Pyramid and on foods made from wheat. The Food Guide Pyramid can be cut out of the pamphlet and assembled as a three-dimensional information source and food guide.…

  7. Wheat Newsletter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This review was written for readers of the Annual Wheat Newsletter, Volume 53. It summarizes activities on wheat research during 2006 at the U.S. Grain Marketing Research Laboratory (USGMRL). The article includes technical abstracts of research accomplishments from the Grain Quality and Structure ...

  8. Variation in Susceptibility to Wheat dwarf virus among Wild and Domesticated Wheat

    PubMed Central

    Nygren, Jim; Shad, Nadeem; Kvarnheden, Anders; Westerbergh, Anna

    2015-01-01

    We investigated the variation in plant response in host-pathogen interactions between wild (Aegilops spp., Triticum spp.) and domesticated wheat (Triticum spp.) and Wheat dwarf virus (WDV). The distribution of WDV and its wild host species overlaps in Western Asia in the Fertile Crescent, suggesting a coevolutionary relationship. Bread wheat originates from a natural hybridization between wild emmer wheat (carrying the A and B genomes) and the wild D genome donor Aegilops tauschii, followed by polyploidization and domestication. We studied whether the strong selection during these evolutionary processes, leading to genetic bottlenecks, may have resulted in a loss of resistance in domesticated wheat. In addition, we investigated whether putative fluctuations in intensity of selection imposed on the host-pathogen interactions have resulted in a variation in susceptibility to WDV. To test our hypotheses we evaluated eighteen wild and domesticated wheat taxa, directly or indirectly involved in wheat evolution, for traits associated with WDV disease such as leaf chlorosis, different growth traits and WDV content. The plants were exposed to viruliferous leafhoppers (Psammotettix alienus) in a greenhouse trial and evaluated at two time points. We found three different plant response patterns: i) continuous reduction in growth over time, ii) weak response at an early stage of plant development but a much stronger response at a later stage, and iii) remission of symptoms over time. Variation in susceptibility may be explained by differences in the intensity of natural selection, shaping the coevolutionary interaction between WDV and the wild relatives. However, genetic bottlenecks during wheat evolution have not had a strong impact on WDV resistance. Further, this study indicates that the variation in susceptibility may be associated with the genome type and that the ancestor Ae. tauschii may be useful as genetic resource for the improvement of WDV resistance in wheat. PMID

  9. Variation in susceptibility to Wheat dwarf virus among wild and domesticated wheat.

    PubMed

    Nygren, Jim; Shad, Nadeem; Kvarnheden, Anders; Westerbergh, Anna

    2015-01-01

    We investigated the variation in plant response in host-pathogen interactions between wild (Aegilops spp., Triticum spp.) and domesticated wheat (Triticum spp.) and Wheat dwarf virus (WDV). The distribution of WDV and its wild host species overlaps in Western Asia in the Fertile Crescent, suggesting a coevolutionary relationship. Bread wheat originates from a natural hybridization between wild emmer wheat (carrying the A and B genomes) and the wild D genome donor Aegilops tauschii, followed by polyploidization and domestication. We studied whether the strong selection during these evolutionary processes, leading to genetic bottlenecks, may have resulted in a loss of resistance in domesticated wheat. In addition, we investigated whether putative fluctuations in intensity of selection imposed on the host-pathogen interactions have resulted in a variation in susceptibility to WDV. To test our hypotheses we evaluated eighteen wild and domesticated wheat taxa, directly or indirectly involved in wheat evolution, for traits associated with WDV disease such as leaf chlorosis, different growth traits and WDV content. The plants were exposed to viruliferous leafhoppers (Psammotettix alienus) in a greenhouse trial and evaluated at two time points. We found three different plant response patterns: i) continuous reduction in growth over time, ii) weak response at an early stage of plant development but a much stronger response at a later stage, and iii) remission of symptoms over time. Variation in susceptibility may be explained by differences in the intensity of natural selection, shaping the coevolutionary interaction between WDV and the wild relatives. However, genetic bottlenecks during wheat evolution have not had a strong impact on WDV resistance. Further, this study indicates that the variation in susceptibility may be associated with the genome type and that the ancestor Ae. tauschii may be useful as genetic resource for the improvement of WDV resistance in wheat. PMID

  10. The Major Threshability Genes Soft Glume (sog) and Tenacious Glume (Tg), of Diploid and Polyploid Wheat, Trace Their Origin to Independent Mutations at Non-Orthogous Loci

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Threshability is an important crop domestication trait. The wild wheat progenitors have tough glumes enveloping the floret that make spikes difficult to thresh, whereas cultivated wheats have soft glumes and are free-threshing. In hexaploid wheat, the glume tenacity gene Tg along with the major dome...

  11. Synteny perturbations between wheat homoeologous chromosomes caused by locus duplications and deletions correlate with recombination rates

    PubMed Central

    Akhunov, Eduard D.; Akhunova, Alina R.; Linkiewicz, Anna M.; Dubcovsky, Jorge; Hummel, David; Lazo, Gerry; Chao, Shiaoman; Anderson, Olin D.; David, Jacques; Qi, Lili; Echalier, Benjamin; Gill, Bikram S.; Miftahudin; Gustafson, J. Perry; La Rota, Mauricio; Sorrells, Mark E.; Zhang, Deshui; Nguyen, Henry T.; Kalavacharla, Venugopal; Hossain, Khwaja; Kianian, Shahryar F.; Peng, Junhua; Lapitan, Nora L. V.; Wennerlind, Emily J.; Nduati, Vivienne; Anderson, James A.; Sidhu, Deepak; Gill, Kulvinder S.; McGuire, Patrick E.; Qualset, Calvin O.; Dvorak, Jan

    2003-01-01

    Loci detected by Southern blot hybridization of 3,977 expressed sequence tag unigenes were mapped into 159 chromosome bins delineated by breakpoints of a series of overlapping deletions. These data were used to assess synteny levels along homoeologous chromosomes of the wheat A, B, and D genomes, in relation to both bin position on the centromere-telomere axis and the gradient of recombination rates along chromosome arms. Synteny level decreased with the distance of a chromosome region from the centromere. It also decreased with an increase in recombination rates along the average chromosome arm. There were twice as many unique loci in the B genome than in the A and D genomes, and synteny levels between the B genome chromosomes and the A and D genome homoeologues were lower than those between the A and D genome homoeologues. These differences among the wheat genomes were attributed to differences in the mating systems of wheat diploid ancestors. Synteny perturbations were characterized in 31 paralogous sets of loci with perturbed synteny. Both insertions and deletions of loci were detected and both preferentially occurred in high recombination regions of chromosomes. PMID:12960374

  12. The diploid D genome cottons (Gossypium spp.) of the new world

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The diploid D genome cottons (Gossypium spp.) of the New World are part of a great reservoir of important genes for improving fiber quality, pest and disease resistance, and drought and salt tolerance in the modern cultivated Upland/Acala (G. hirsutum) and Pima [also known as Sea Island or Egyptian ...

  13. Development of high amylose wheat through TILLING

    PubMed Central

    2012-01-01

    Background Wheat (Triticum spp.) is an important source of food worldwide and the focus of considerable efforts to identify new combinations of genetic diversity for crop improvement. In particular, wheat starch composition is a major target for changes that could benefit human health. Starches with increased levels of amylose are of interest because of the correlation between higher amylose content and elevated levels of resistant starch, which has been shown to have beneficial effects on health for combating obesity and diabetes. TILLING (Targeting Induced Local Lesions in Genomes) is a means to identify novel genetic variation without the need for direct selection of phenotypes. Results Using TILLING to identify novel genetic variation in each of the A and B genomes in tetraploid durum wheat and the A, B and D genomes in hexaploid bread wheat, we have identified mutations in the form of single nucleotide polymorphisms (SNPs) in starch branching enzyme IIa genes (SBEIIa). Combining these new alleles of SBEIIa through breeding resulted in the development of high amylose durum and bread wheat varieties containing 47-55% amylose and having elevated resistant starch levels compared to wild-type wheat. High amylose lines also had reduced expression of SBEIIa RNA, changes in starch granule morphology and altered starch granule protein profiles as evaluated by mass spectrometry. Conclusions We report the use of TILLING to develop new traits in crops with complex genomes without the use of transgenic modifications. Combined mutations in SBEIIa in durum and bread wheat varieties resulted in lines with significantly increased amylose and resistant starch contents. PMID:22584013

  14. Acc homoeoloci and the evolution of wheat genomes

    PubMed Central

    Chalupska, D.; Lee, H. Y.; Faris, J. D.; Evrard, A.; Chalhoub, B.; Haselkorn, R.; Gornicki, P.

    2008-01-01

    The DNA sequences of wheat Acc-1 and Acc-2 loci, encoding the plastid and cytosolic forms of the enzyme acetyl-CoA carboxylase, were analyzed with a view to understanding the evolution of these genes and the origin of the three genomes in modern hexaploid wheat. Acc-1 and Acc-2 loci from each of the wheats Triticum urartu (A genome), Aegilops tauschii (D genome), Triticum turgidum (AB genome), and Triticum aestivum (ABD genome), as well as two Acc-2-related pseudogenes from T. urartu were sequenced. The 2.3–2.4 Mya divergence time calculated here for the three homoeologous chromosomes, on the basis of coding and intron sequences of the Acc-1 genes, is at the low end of other estimates. Our clock was calibrated by using 60 Mya for the divergence between wheat and maize. On the same time scale, wheat and barley diverged 11.6 Mya, based on sequences of Acc and other genes. The regions flanking the Acc genes are not conserved among the A, B, and D genomes. They are conserved when comparing homoeologous genomes of diploid, tetraploid, and hexaploid wheats. Substitution rates in intergenic regions consisting primarily of repetitive sequences vary substantially along the loci and on average are 3.5-fold higher than the Acc intron substitution rates. The composition of the Acc homoeoloci suggests haplotype divergence exceeding in some cases 0.5 Mya. Such variation might result in a significant overestimate of the time since tetraploid wheat formation, which occurred no more than 0.5 Mya. PMID:18599450

  15. Acc homoeoloci and the evolution of wheat genomes.

    PubMed

    Chalupska, D; Lee, H Y; Faris, J D; Evrard, A; Chalhoub, B; Haselkorn, R; Gornicki, P

    2008-07-15

    The DNA sequences of wheat Acc-1 and Acc-2 loci, encoding the plastid and cytosolic forms of the enzyme acetyl-CoA carboxylase, were analyzed with a view to understanding the evolution of these genes and the origin of the three genomes in modern hexaploid wheat. Acc-1 and Acc-2 loci from each of the wheats Triticum urartu (A genome), Aegilops tauschii (D genome), Triticum turgidum (AB genome), and Triticum aestivum (ABD genome), as well as two Acc-2-related pseudogenes from T. urartu were sequenced. The 2.3-2.4 Mya divergence time calculated here for the three homoeologous chromosomes, on the basis of coding and intron sequences of the Acc-1 genes, is at the low end of other estimates. Our clock was calibrated by using 60 Mya for the divergence between wheat and maize. On the same time scale, wheat and barley diverged 11.6 Mya, based on sequences of Acc and other genes. The regions flanking the Acc genes are not conserved among the A, B, and D genomes. They are conserved when comparing homoeologous genomes of diploid, tetraploid, and hexaploid wheats. Substitution rates in intergenic regions consisting primarily of repetitive sequences vary substantially along the loci and on average are 3.5-fold higher than the Acc intron substitution rates. The composition of the Acc homoeoloci suggests haplotype divergence exceeding in some cases 0.5 Mya. Such variation might result in a significant overestimate of the time since tetraploid wheat formation, which occurred no more than 0.5 Mya. PMID:18599450

  16. A low-latency, big database system and browser for storage, querying and visualization of 3D genomic data.

    PubMed

    Butyaev, Alexander; Mavlyutov, Ruslan; Blanchette, Mathieu; Cudré-Mauroux, Philippe; Waldispühl, Jérôme

    2015-09-18

    Recent releases of genome three-dimensional (3D) structures have the potential to transform our understanding of genomes. Nonetheless, the storage technology and visualization tools need to evolve to offer to the scientific community fast and convenient access to these data. We introduce simultaneously a database system to store and query 3D genomic data (3DBG), and a 3D genome browser to visualize and explore 3D genome structures (3DGB). We benchmark 3DBG against state-of-the-art systems and demonstrate that it is faster than previous solutions, and importantly gracefully scales with the size of data. We also illustrate the usefulness of our 3D genome Web browser to explore human genome structures. The 3D genome browser is available at http://3dgb.cs.mcgill.ca/. PMID:25990738

  17. A low-latency, big database system and browser for storage, querying and visualization of 3D genomic data

    PubMed Central

    Butyaev, Alexander; Mavlyutov, Ruslan; Blanchette, Mathieu; Cudré-Mauroux, Philippe; Waldispühl, Jérôme

    2015-01-01

    Recent releases of genome three-dimensional (3D) structures have the potential to transform our understanding of genomes. Nonetheless, the storage technology and visualization tools need to evolve to offer to the scientific community fast and convenient access to these data. We introduce simultaneously a database system to store and query 3D genomic data (3DBG), and a 3D genome browser to visualize and explore 3D genome structures (3DGB). We benchmark 3DBG against state-of-the-art systems and demonstrate that it is faster than previous solutions, and importantly gracefully scales with the size of data. We also illustrate the usefulness of our 3D genome Web browser to explore human genome structures. The 3D genome browser is available at http://3dgb.cs.mcgill.ca/. PMID:25990738

  18. Wheat: The Whole Story.

    ERIC Educational Resources Information Center

    Oklahoma State Dept. of Education, Oklahoma City.

    This publication presents information on wheat. Wheat was originally a wild grass and not native to the United States. Wheat was not planted there until 1777 (and then only as a hobby crop). Wheat is grown on more acres than any other grain in this country. Soft wheats are grown east of the Mississippi River, and hard wheats are grown west of the…

  19. Variation in the wheat AP2 homoeologs, the genes underlying lodicule development.

    PubMed

    Ning, Shunzong; Wang, Ning; Sakuma, Shun; Pourkheirandish, Mohammad; Koba, Takato; Komatsuda, Takao

    2013-09-01

    The bread wheat genome harbors three homoeologs of the barley gene HvAP2, which determines the cleistogamous/non-cleistogamous flowering. The three homoeologs, TaAP2-A, TaAP2-B and TaAP2-D, are derived from the A, B and D genomes. The importance of lodicule swelling in assuring non-cleistogamous flowering in a range of wild and domesticated wheat accessions of varying ploidy level was established. Re-sequencing of wheat AP2 homoeologous genes was carried out to identify natural variation at both the nucleotide and polypeptide level. The sequences of wheat AP2 homoeologs are highly conserved even across different ploidy levels and no functional variants at the key miR172 targeting site were detected. These results indicate that engineering of cleistogamous wheat will require the presence of a functional TaAP2 modification at each of the three homoeologs. PMID:24273420

  20. Wheat Lipids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This article is a chapter of a book entitled “Wheat: Chemistry and Technology”, the 4th edition, K. Khan and P.R. Shewry (eds.), to be published in 2007 following the 3rd edition, Y. Pomeranz (ed.), published in 1988 by AACC International Inc., St. Paul, MN. The chapter covers the subject area of wh...

  1. GENES ENCODING PLASTID ACETYL-COA CARBOXYLASE AND 3-PHOSPHOGLYCERATE KINASE OF THE TRITICUM/AEGILOPS COMPLEX AND THE EVOLUTIONARY HISTORY OF POLYPLOID WHEAT.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The classic wheat evolutionary history is one of adaptive radiation of the diploid Triticum/Aegilops species (A, S, D) , genome convergence and divergence of the tetraploid (T. turgidum AABB, and T. timopheevii AAAGG) and hexaploid (T. aestivum, AABBDD) species. The objective of this study was to a...

  2. Manifold Based Optimization for Single-Cell 3D Genome Reconstruction

    PubMed Central

    Collas, Philippe

    2015-01-01

    The three-dimensional (3D) structure of the genome is important for orchestration of gene expression and cell differentiation. While mapping genomes in 3D has for a long time been elusive, recent adaptations of high-throughput sequencing to chromosome conformation capture (3C) techniques, allows for genome-wide structural characterization for the first time. However, reconstruction of "consensus" 3D genomes from 3C-based data is a challenging problem, since the data are aggregated over millions of cells. Recent single-cell adaptations to the 3C-technique, however, allow for non-aggregated structural assessment of genome structure, but data suffer from sparse and noisy interaction sampling. We present a manifold based optimization (MBO) approach for the reconstruction of 3D genome structure from chromosomal contact data. We show that MBO is able to reconstruct 3D structures based on the chromosomal contacts, imposing fewer structural violations than comparable methods. Additionally, MBO is suitable for efficient high-throughput reconstruction of large systems, such as entire genomes, allowing for comparative studies of genomic structure across cell-lines and different species. PMID:26262780

  3. CTCF-Mediated Human 3D Genome Architecture Reveals Chromatin Topology for Transcription.

    PubMed

    Tang, Zhonghui; Luo, Oscar Junhong; Li, Xingwang; Zheng, Meizhen; Zhu, Jacqueline Jufen; Szalaj, Przemyslaw; Trzaskoma, Pawel; Magalska, Adriana; Wlodarczyk, Jakub; Ruszczycki, Blazej; Michalski, Paul; Piecuch, Emaly; Wang, Ping; Wang, Danjuan; Tian, Simon Zhongyuan; Penrad-Mobayed, May; Sachs, Laurent M; Ruan, Xiaoan; Wei, Chia-Lin; Liu, Edison T; Wilczynski, Grzegorz M; Plewczynski, Dariusz; Li, Guoliang; Ruan, Yijun

    2015-12-17

    Spatial genome organization and its effect on transcription remains a fundamental question. We applied an advanced chromatin interaction analysis by paired-end tag sequencing (ChIA-PET) strategy to comprehensively map higher-order chromosome folding and specific chromatin interactions mediated by CCCTC-binding factor (CTCF) and RNA polymerase II (RNAPII) with haplotype specificity and nucleotide resolution in different human cell lineages. We find that CTCF/cohesin-mediated interaction anchors serve as structural foci for spatial organization of constitutive genes concordant with CTCF-motif orientation, whereas RNAPII interacts within these structures by selectively drawing cell-type-specific genes toward CTCF foci for coordinated transcription. Furthermore, we show that haplotype variants and allelic interactions have differential effects on chromosome configuration, influencing gene expression, and may provide mechanistic insights into functions associated with disease susceptibility. 3D genome simulation suggests a model of chromatin folding around chromosomal axes, where CTCF is involved in defining the interface between condensed and open compartments for structural regulation. Our 3D genome strategy thus provides unique insights in the topological mechanism of human variations and diseases. PMID:26686651

  4. Homoeologous copy-specific expression patterns of MADS-box genes for floral formation in allopolyploid wheat.

    PubMed

    Tanaka, Miku; Tanaka, Hiroko; Shitsukawa, Naoki; Kitagawa, Satoshi; Takumi, Shigeo; Murai, Koji

    2016-01-01

    The consensus model for floral organ formation in higher plants, the so-called ABCDE model, proposes that floral whorl-specific combinations of class A, B, C, D, and E genes specify floral organ identity. Class A, B, C, D and E genes encode MADS-box transcription factors; the single exception being the class A gene APETALA2. Bread wheat (Triticum aestivum) is a hexaploid species with a genome constitution AABBDD; the hexaploid originated from a cross between tetraploid T. turgidum (AABB) and diploid Aegilops tauschii (DD). Tetraploid wheat is thought to have originated from a cross between the diploid species T. urartu (AA) and Ae. speltoides (BB). Consequently, the hexaploid wheat genome contains triplicated homoeologous copies (homoeologs) of each gene derived from the different ancestral diploid species. In this study, we examined the expression patterns of homoeologs of class B, C and D MADS-box genes during floral development. For the class B gene wheat PISTILLATA2 (WPI2), the homoeologs from the A and D genomes were expressed, while expression of the B genome homoeolog was suppressed. For the class C gene wheat AGAMOUS1 (WAG1), the homoeologs on the A and B genomes were expressed, while expression of the D genome homoeolog was suppressed. For the class D gene wheat SEEDSTICK (WSTK), the B genome homoeolog was preferentially expressed. These differential patterns of homoeolog expression were consistently observed among different hexaploid wheat varieties and synthetic hexaploid wheat lines developed by artificial crosses between tetraploid wheat and Ae. tauschii. These results suggest that homoeolog-specific regulation of the floral MADS-box genes occurs in allopolyploid wheat. PMID:26616759

  5. Evolutionary Genomics of Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat is the world’s largest and most important food crop for direct human consumption, therefore, continued wheat improvement is paramount for feeding an ever-increasing human population. Wheat improvement is tightly associated with the characterization and understanding of wheat evolution and gene...

  6. Spring Wheat Breeding

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Common wheat, known as bread wheat, is one of major crops for human food consumption. It is further classified into spring and winter wheat based on the distinct growing seasons. Spring wheat is grown worldwide and usually planted in the spring and harvested in late summer or early fall. In this c...

  7. Cell-of-Origin-Specific 3D Genome Structure Acquired during Somatic Cell Reprogramming

    PubMed Central

    Krijger, Peter Hugo Lodewijk; Di Stefano, Bruno; de Wit, Elzo; Limone, Francesco; van Oevelen, Chris; de Laat, Wouter; Graf, Thomas

    2016-01-01

    Summary Forced expression of reprogramming factors can convert somatic cells into induced pluripotent stem cells (iPSCs). Here we studied genome topology dynamics during reprogramming of different somatic cell types with highly distinct genome conformations. We find large-scale topologically associated domain (TAD) repositioning and alterations of tissue-restricted genomic neighborhoods and chromatin loops, effectively erasing the somatic-cell-specific genome structures while establishing an embryonic stem-cell-like 3D genome. Yet, early passage iPSCs carry topological hallmarks that enable recognition of their cell of origin. These hallmarks are not remnants of somatic chromosome topologies. Instead, the distinguishing topological features are acquired during reprogramming, as we also find for cell-of-origin-dependent gene expression patterns. PMID:26971819

  8. Reconciliation of D-genome puroindoline allele designations with current DNA sequence data.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Kernel texture is an important trait in cereals, especially wheat (Triticum sp.). Throughout the Triticeae, the puroindoline genes act to soften kernel endosperm. Absence or mutation of either or both of the two puroindolines, ‘a’ and ‘b’, in T. aestivum results in harder grain texture. Apparent...

  9. Functional Blood Progenitor Markers in Developing Human Liver Progenitors.

    PubMed

    Goldman, Orit; Cohen, Idan; Gouon-Evans, Valerie

    2016-08-01

    In the early fetal liver, hematopoietic progenitors expand and mature together with hepatoblasts, the liver progenitors of hepatocytes and cholangiocytes. Previous analyses of human fetal livers indicated that both progenitors support each other's lineage maturation and curiously share some cell surface markers including CD34 and CD133. Using the human embryonic stem cell (hESC) system, we demonstrate that virtually all hESC-derived hepatoblast-like cells (Hep cells) transition through a progenitor stage expressing CD34 and CD133 as well as GATA2, an additional hematopoietic marker that has not previously been associated with human hepatoblast development. Dynamic expression patterns for CD34, CD133, and GATA2 in hepatoblasts were validated in human fetal livers collected from the first and second trimesters of gestation. Knockdown experiments demonstrate that each gene also functions to regulate hepatic fate mostly in a cell-autonomous fashion, revealing unprecedented roles of fetal hematopoietic progenitor markers in human liver progenitors. PMID:27509132

  10. Progenitors of type Ia supernovae

    NASA Astrophysics Data System (ADS)

    Maeda, Keiichi; Terada, Yukikatsu

    2016-07-01

    Natures of progenitors of type Ia Supernovae (SNe Ia) have not yet been clarified. There has been long and intensive discussion on whether the so-called single degenerate (SD) scenario or the double degenerate (DD) scenario, or anything else, could explain a major population of SNe Ia, but the conclusion has not yet been reached. With rapidly increasing observational data and new theoretical ideas, the field of studying the SN Ia progenitors has been quickly developing, and various new insights have been obtained in recent years. This paper aims at providing a summary of the current situation regarding the SN Ia progenitors, both in theory and observations. It seems difficult to explain the emerging diversity seen in observations of SNe Ia by a single population, and we emphasize that it is important to clarify links between different progenitor scenarios and different sub-classes of SNe Ia.

  11. Molecular cytogenetic characterization of novel wheat-Thinopyrum bessarabicum recombinant lines carrying intercalary translocations.

    PubMed

    Patokar, Chetan; Sepsi, Adel; Schwarzacher, Trude; Kishii, Masahiro; Heslop-Harrison, J S

    2016-03-01

    Thinopyrum bessarabicum (2n = 2x = 14, JJ or E(b)E(b)) is a valuable source of genes for bread wheat (2n = 6x = 42) improvement because of its salinity tolerance and disease resistance. Development of wheat-Th. bessarabicum translocation lines by backcrossing the amphiploid in the absence of the Ph1 gene (allowing intergenomic recombination) can assist its utilization in wheat improvement. In this study, six novel wheat-Th. bessarabicum translocation lines involving different chromosome segments (T4BS.4BL-4JL, T6BS.6BL-6JL, T5AS.5AL-5JL, T5DL.5DS-5JS, T2BS.2BL-2JL, and the whole arm translocation T1JS.1AL) were identified and characterized using genomic in situ hybridization (GISH) and fluorescent in situ hybridization (FISH). No background translocations between wheat genomes were observed. The involvement of five of the seven chromosomes and small terminal segments of Th. bessarabicum chromosome arm were important, contributing to both reduced linkage drag of the derived lines by minimizing agronomically deleterious genes from the alien species and high stability including transmission of the alien segment. All three wheat genomes were involved in the translocations with the alien chromosome, and GISH showed the Th. bessarabicum genome was more closely related to the D genome in wheat. All the introgression lines were disomic, stable, and with good morphological characters. PMID:26238987

  12. Generation of amphidiploids from hybrids of wheat and related species from the genera Aegilops, Secale, Thinopyrum, and Triticum as a source of genetic variation for wheat improvement.

    PubMed

    Nemeth, Csilla; Yang, Cai-yun; Kasprzak, Paul; Hubbart, Stella; Scholefield, Duncan; Mehra, Surbhi; Skipper, Emma; King, Ian; King, Julie

    2015-02-01

    We aim to improve diversity of domesticated wheat by transferring genetic variation for important target traits from related wild and cultivated grass species. The present study describes the development of F1 hybrids between wheat and related species from the genera Aegilops, Secale, Thinopyrum, and Triticum and production of new amphidiploids. Amphidiploid lines were produced from 20 different distant relatives. Both colchicine and caffeine were successfully used to double the chromosome numbers. The genomic constitution of the newly formed amphidiploids derived from seven distant relatives was determined using genomic in situ hybridization (GISH). Altogether, 42 different plants were analysed, 19 using multicolour GISH separating the chromosomes from the A, B, and D genomes of wheat, as well as the distant relative, and 23 using single colour GISH. Restructuring of the allopolyploid genome, both chromosome losses and aneuploidy, was detected in all the genomes contained by the amphidiploids. From the observed chromosome numbers there is an indication that in amphidiploids the B genome of wheat suffers chromosome losses less frequently than the other wheat genomes. Phenotyping to realize the full potential of the wheat-related grass germplasm is underway, linking the analyzed genotypes to agronomically important target traits. PMID:26053312

  13. Wheat: Science and Trade

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This is for a book review of Wheat: science and trade, edited by B.F. Carver. The book provides an indepth review of wheat biology, production, breeding, processing, and trade and is organized in four sections. "Making of a Wheat Plant" reviews domestication, evolution, development, and molecular ...

  14. Proteomics of Wheat Flour

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat is a major food crop grown on more than 215 million hectares of land throughout the world. Wheat flour provides an important source of protein for human nutrition and is used as a principal ingredient in a wide range of food products, largely because wheat flour, when mixed with water, has un...

  15. Wheat Stripe Rust

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This is a chapter on wheat stripe rust in a book entitled “Wheat: Science and Trade”. The chapter provides an overview on various aspects of wheat stripe rust and control, including distribution and epidemiology; origin and historical importance; taxonomy, lifecycle, and host range; genetic variati...

  16. 3D-GNOME: an integrated web service for structural modeling of the 3D genome

    PubMed Central

    Szalaj, Przemyslaw; Michalski, Paul J.; Wróblewski, Przemysław; Tang, Zhonghui; Kadlof, Michal; Mazzocco, Giovanni; Ruan, Yijun; Plewczynski, Dariusz

    2016-01-01

    Recent advances in high-throughput chromosome conformation capture (3C) technology, such as Hi-C and ChIA-PET, have demonstrated the importance of 3D genome organization in development, cell differentiation and transcriptional regulation. There is now a widespread need for computational tools to generate and analyze 3D structural models from 3C data. Here we introduce our 3D GeNOme Modeling Engine (3D-GNOME), a web service which generates 3D structures from 3C data and provides tools to visually inspect and annotate the resulting structures, in addition to a variety of statistical plots and heatmaps which characterize the selected genomic region. Users submit a bedpe (paired-end BED format) file containing the locations and strengths of long range contact points, and 3D-GNOME simulates the structure and provides a convenient user interface for further analysis. Alternatively, a user may generate structures using published ChIA-PET data for the GM12878 cell line by simply specifying a genomic region of interest. 3D-GNOME is freely available at http://3dgnome.cent.uw.edu.pl/. PMID:27185892

  17. 3D-GNOME: an integrated web service for structural modeling of the 3D genome.

    PubMed

    Szalaj, Przemyslaw; Michalski, Paul J; Wróblewski, Przemysław; Tang, Zhonghui; Kadlof, Michal; Mazzocco, Giovanni; Ruan, Yijun; Plewczynski, Dariusz

    2016-07-01

    Recent advances in high-throughput chromosome conformation capture (3C) technology, such as Hi-C and ChIA-PET, have demonstrated the importance of 3D genome organization in development, cell differentiation and transcriptional regulation. There is now a widespread need for computational tools to generate and analyze 3D structural models from 3C data. Here we introduce our 3D GeNOme Modeling Engine (3D-GNOME), a web service which generates 3D structures from 3C data and provides tools to visually inspect and annotate the resulting structures, in addition to a variety of statistical plots and heatmaps which characterize the selected genomic region. Users submit a bedpe (paired-end BED format) file containing the locations and strengths of long range contact points, and 3D-GNOME simulates the structure and provides a convenient user interface for further analysis. Alternatively, a user may generate structures using published ChIA-PET data for the GM12878 cell line by simply specifying a genomic region of interest. 3D-GNOME is freely available at http://3dgnome.cent.uw.edu.pl/. PMID:27185892

  18. Population-based 3D genome structure analysis reveals driving forces in spatial genome organization

    PubMed Central

    Li, Wenyuan; Kalhor, Reza; Dai, Chao; Hao, Shengli; Gong, Ke; Zhou, Yonggang; Li, Haochen; Zhou, Xianghong Jasmine; Le Gros, Mark A.; Larabell, Carolyn A.; Chen, Lin; Alber, Frank

    2016-01-01

    Conformation capture technologies (e.g., Hi-C) chart physical interactions between chromatin regions on a genome-wide scale. However, the structural variability of the genome between cells poses a great challenge to interpreting ensemble-averaged Hi-C data, particularly for long-range and interchromosomal interactions. Here, we present a probabilistic approach for deconvoluting Hi-C data into a model population of distinct diploid 3D genome structures, which facilitates the detection of chromatin interactions likely to co-occur in individual cells. Our approach incorporates the stochastic nature of chromosome conformations and allows a detailed analysis of alternative chromatin structure states. For example, we predict and experimentally confirm the presence of large centromere clusters with distinct chromosome compositions varying between individual cells. The stability of these clusters varies greatly with their chromosome identities. We show that these chromosome-specific clusters can play a key role in the overall chromosome positioning in the nucleus and stabilizing specific chromatin interactions. By explicitly considering genome structural variability, our population-based method provides an important tool for revealing novel insights into the key factors shaping the spatial genome organization. PMID:26951677

  19. Mining 3D genome structure populations identifies major factors governing the stability of regulatory communities

    PubMed Central

    Dai, Chao; Li, Wenyuan; Tjong, Harianto; Hao, Shengli; Zhou, Yonggang; Li, Qingjiao; Chen, Lin; Zhu, Bing; Alber, Frank; Jasmine Zhou, Xianghong

    2016-01-01

    Three-dimensional (3D) genome structures vary from cell to cell even in an isogenic sample. Unlike protein structures, genome structures are highly plastic, posing a significant challenge for structure-function mapping. Here we report an approach to comprehensively identify 3D chromatin clusters that each occurs frequently across a population of genome structures, either deconvoluted from ensemble-averaged Hi-C data or from a collection of single-cell Hi-C data. Applying our method to a population of genome structures (at the macrodomain resolution) of lymphoblastoid cells, we identify an atlas of stable inter-chromosomal chromatin clusters. A large number of these clusters are enriched in binding of specific regulatory factors and are therefore defined as ‘Regulatory Communities.' We reveal two major factors, centromere clustering and transcription factor binding, which significantly stabilize such communities. Finally, we show that the regulatory communities differ substantially from cell to cell, indicating that expression variability could be impacted by genome structures. PMID:27240697

  20. CRISPR Double Cutting through the Labyrinthine Architecture of 3D Genomes.

    PubMed

    Huang, Haiyan; Wu, Qiang

    2016-05-20

    The genomes are organized into ordered and hierarchical topological structures in interphase nuclei. Within discrete territories of each chromosome, topologically associated domains (TADs) play important roles in various nuclear processes such as gene regulation. Inside TADs separated by relatively constitutive boundaries, distal elements regulate their gene targets through specific chromatin-looping contacts such as long-distance enhancer-promoter interactions. High-throughput sequencing studies have revealed millions of potential regulatory DNA elements, which are much more abundant than the mere ∼20,000 genes they control. The recently emerged CRISPR-Cas9 genome editing technologies have enabled efficient and precise genetic and epigenetic manipulations of genomes. The multiplexed and high-throughput CRISPR capabilities facilitate the discovery and dissection of gene regulatory elements. Here, we describe the applications of CRISPR for genome, epigenome, and 3D genome editing, focusing on CRISPR DNA-fragment editing with Cas9 and a pair of sgRNAs to investigate topological folding of chromatin TADs and developmental gene regulation. PMID:27210040

  1. Embryonic Heart Progenitors and Cardiogenesis

    PubMed Central

    Brade, Thomas; Pane, Luna S.; Moretti, Alessandra; Chien, Kenneth R.; Laugwitz, Karl-Ludwig

    2013-01-01

    The mammalian heart is a highly specialized organ, comprised of many different cell types arising from distinct embryonic progenitor populations during cardiogenesis. Three precursor populations have been identified to contribute to different myocytic and nonmyocytic cell lineages of the heart: cardiogenic mesoderm cells (CMC), the proepicardium (PE), and cardiac neural crest cells (CNCCs). This review will focus on molecular cues necessary for proper induction, expansion, and lineage-specific differentiation of these progenitor populations during cardiac development in vivo. Moreover, we will briefly discuss how the knowledge gained on embryonic heart progenitor biology can be used to develop novel therapeutic strategies for the management of congenital heart disease as well as for improvement of cardiac function in ischemic heart disease. PMID:24086063

  2. The Progenitors of Thermonuclear Supernovae

    SciTech Connect

    Piersanti, L.; Straniero, O.; Tornambe, A.; Dominguez, I.

    2009-05-03

    In the framework of the rotating Double Degenerate Scenario for type Ia Supernovae progenitors, we show that the dichotomy between explosive events in early and late type galaxies can be easily explained. Assuming that more massive progenitors produce slow-decline (high-luminosity) light curve, it comes out that, at the current age of the Universe, in late type galaxies the continuous star formation provides very massive exploding objects (prompt component) corresponding to slow-decline (bright) SNe; on the other hand, in early type galaxies, where star formation ended many billions years ago, only low mass ''normal luminosity'' objects (delayed component) are present.

  3. Asymmetric Epigenetic Modification and Elimination of rDNA Sequences by Polyploidization in Wheat[W

    PubMed Central

    Guo, Xiang

    2014-01-01

    rRNA genes consist of long tandem repeats clustered on chromosomes, and their products are important functional components of the ribosome. In common wheat (Triticum aestivum), rDNA loci from the A and D genomes were largely lost during the evolutionary process. This biased DNA elimination may be related to asymmetric transcription and epigenetic modifications caused by the polyploid formation. Here, we observed both sets of parental nucleolus organizing regions (NORs) were expressed after hybridization, but asymmetric silencing of one parental NOR was immediately induced by chromosome doubling, and reversing the ploidy status could not reactivate silenced NORs. Furthermore, increased CHG and CHH DNA methylation on promoters was accompanied by asymmetric silencing of NORs. Enrichment of H3K27me3 and H3K9me2 modifications was also observed to be a direct response to increased DNA methylation and transcriptional inactivation of NOR loci. Both A and D genome NOR loci with these modifications started to disappear in the S4 generation and were completely eliminated by the S7 generation in synthetic tetraploid wheat. Our results indicated that asymmetric epigenetic modification and elimination of rDNA sequences between different donor genomes may lead to stable allopolyploid wheat with increased differentiation and diversity. PMID:25415973

  4. Asymmetric epigenetic modification and elimination of rDNA sequences by polyploidization in wheat.

    PubMed

    Guo, Xiang; Han, Fangpu

    2014-11-01

    rRNA genes consist of long tandem repeats clustered on chromosomes, and their products are important functional components of the ribosome. In common wheat (Triticum aestivum), rDNA loci from the A and D genomes were largely lost during the evolutionary process. This biased DNA elimination may be related to asymmetric transcription and epigenetic modifications caused by the polyploid formation. Here, we observed both sets of parental nucleolus organizing regions (NORs) were expressed after hybridization, but asymmetric silencing of one parental NOR was immediately induced by chromosome doubling, and reversing the ploidy status could not reactivate silenced NORs. Furthermore, increased CHG and CHH DNA methylation on promoters was accompanied by asymmetric silencing of NORs. Enrichment of H3K27me3 and H3K9me2 modifications was also observed to be a direct response to increased DNA methylation and transcriptional inactivation of NOR loci. Both A and D genome NOR loci with these modifications started to disappear in the S4 generation and were completely eliminated by the S7 generation in synthetic tetraploid wheat. Our results indicated that asymmetric epigenetic modification and elimination of rDNA sequences between different donor genomes may lead to stable allopolyploid wheat with increased differentiation and diversity. PMID:25415973

  5. Progenitor Cells and Podocyte Regeneration

    PubMed Central

    Shankland, Stuart J.; Pippin, Jeffrey W.; Duffield, Jeremy S.

    2014-01-01

    The very limited ability of adult podocytes to proliferate in vivo is clinically significant because: podocytes form a vascular barrier which is functionally critical to the nephron; podocyte hypoplasia is a characteristic of disease; and inadequate regeneration of podocytes is a major cause of persistent podocyte hypoplasia. Excessive podocyte loss or inadequate replacement leads to glomerulosclerosis in many progressive kidney diseases. Thus, restoration of podocyte cell density is almost certainly reliant on regeneration by podocyte progenitors. However such putative progenitors have remained elusive until recently. In this review we describe the developmental processes leading to podocyte and parietal epithelial cell (PEC) formation during glomerulogenesis. We compare evidence that in normal human kidneys PECs expressing ‘progenitor’ markers CD133 and CD24 can differentiate into podocytes in vitro and in vivo with evidence from animal models suggesting a more limited role of PEC-capacity to serve as podocyte progenitors in adults. We will highlight tantalizing new evidence that specialized vascular wall cells of afferent arterioles including those which produce renin in healthy kidney, provide a novel local progenitor source of new PECs and podocytes in response to podocyte hypoplasia in the adult, and draw comparisons with glomerulogenesis. PMID:25217270

  6. Development of a Set of Stem Rust Susceptible D-Genome Disomic Substitutions Based on Rusty durum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stem rust (Puccinia graminis Pers.:Pers. f.sp. tritici Eriks. and Henn.) is one of the most devastating diseases of wheat (Triticum aestivum L.) and durum (T. turgidum L. ssp. durum). Prior to the development of molecular techniques, studies of genes for stem rust resistance genes in wheat were com...

  7. Short, natural, and extended photoperiod response in BC2F4 lines of bread wheat with different photoperiod-1 (Ppd-1) alleles.

    PubMed

    Bentley, A R; Horsnell, R; Werner, C P; Turner, A S; Rose, G A; Bedard, C; Howell, P; Wilhelm, E P; Mackay, I J; Howells, R M; Greenland, A; Laurie, D A; Gosman, N

    2013-04-01

    Flowering is a critical period in the life cycle of flowering plant species, resulting in an irreversible commitment of significant resources. Wheat is photoperiod sensitive, flowering only when daylength surpasses a critical length; however, photoperiod insensitivity (PI) has been selected by plant breeders for >40 years to enhance yield in certain environments. Control of flowering time has been greatly facilitated by the development of molecular markers for the Photoperiod-1 (Ppd-1) homeoloci, on the group 2 chromosomes. In the current study, an allelic series of BC2F4 lines in the winter wheat cultivars 'Robigus' and 'Alchemy' was developed to elucidate the influence on flowering of eight gene variants from the B- and D-genomes of bread wheat and the A-genome of durum wheat. Allele effects were tested in short, natural, and extended photoperiods in the field and controlled environments. Across genetic background and treatment, the D-genome PI allele, Ppd-D1a, had a more potent effect on reducing flowering time than Ppd-B1a. However, there was significant donor allele effect for both Ppd-D1a and Ppd-B1a, suggesting the presence of linked modifier genes and/or additional sources of latent sensitivity. Development of Ppd-A1a BC2F4 lines derived from synthetic hexaploid wheat provided an opportunity to compare directly the flowering time effect of the A-genome allele from durum with the B- and D-genome variants from bread wheat for the first time. Analyses indicated that the reducing effect of Ppd-A1a is comparable with that of Ppd-D1a, confirming it as a useful alternative source of PI. PMID:23420880

  8. The origin of the B-genome of bread wheat (Triticum aestivum L.).

    PubMed

    Haider, N

    2013-03-01

    Understanding the origin of cultivated wheats would further their genetic improvement. The hexaploid bread wheat (Triticum aestivum L., AABBDD) is believed to have originated through one or more rare hybridization events between Aegilops tauschii (DD) and the tetraploid T. turgidum (AABB). Progenitor of the A-genome of the tetraploid and hexaploid wheats has generally been accepted to be T. urartu. In spite of the large number of attempts and published reports about the origin of the B-genome in cultivated wheats, the donor of the B-genome is still relatively unknown and controversial and, hence, remains open. This genome has been found to be closely related to the S-genome of the Sitopsis section (Ae. speltoides, Ae. longissima, Ae. sharonensis, Ae. searsii, and Ae. bicornis) of the genus Aegilops L. Among Sitopsis species, the most positive evidence has been accumulated for Ae. speltoides as the progenitor of the B-genome. Therefore, one or more of the Sitopsis species were proposed frequently as the B-genome donor. Although several reviews have been written on the origin of the genomes of wheat over the years, this paper will attempt for the first time to review the immense literature on the subject, with a particular emphasis on the B-genome which has attracted a huge attention over some 100 years. The ambiguity and conflicting results in most of the methods employed in deducing the precise B-genome donor/s to bread wheat are also discussed. PMID:23755530

  9. Divergent Development of Hexaploid Triticale by a Wheat - Rye -Psathyrostachys huashanica Trigeneric Hybrid Method.

    PubMed

    Kang, Houyang; Wang, Hao; Huang, Juan; Wang, Yujie; Li, Daiyan; Diao, Chengdou; Zhu, Wei; Tang, Yao; Wang, Yi; Fan, Xing; Zeng, Jian; Xu, Lili; Sha, Lina; Zhang, Haiqin; Zhou, Yonghong

    2016-01-01

    Hexaploid triticale is an important forage crop and a promising energy plant. Some forms were previously reported for developing the hexaploid triticale, such as crossing tetraploid wheat or hexaploid wheat with rye, crossing hexaploid triticale and/or hexaploid wheat with octoploid triticale, and spontaneously appearing in the selfed progenies of octoploid triticale. In the present study, we developed an effective method for production of diverse types of hexaploid triticale via wheat-rye-Psathyrostachys huashanica trigeneric hybrid. Genomic in situ hybridization (GISH) and fluorescence in situ hybridization (FISH) karyotyping revealed that D genome chromosomes were completely eliminated and the whole A, B, and R genome chromosomes were retained in three lines. More interestingly, the composite genome of the line K14-489-2 consisted of complete A and B genomes and chromosomes 1D, 2R, 3R, 4R, 5R, 6R, and 7R, that of line K14-491-2 was 12 A-genome (1A-6A), 14 B-genome (1B-7B), 12 R-genome (1R-3R, 5R-7R), and chromosomes 1D and 3D, and that of the line K14-547-1 had 26A/B and 14R chromosomes, plus one pair of centric 6BL/2DS translocations. This finding implies that some of D genome chromosomes can be spontaneously and stably incorporated into the hexaploid triticale. Additionally, a variety of high-molecular-weight glutenin subunits (HMW-GS) compositions were detected in the six hexaploid triticale lines, respectively. Besides, compared with its recurrent triticale parent Zhongsi828, these lines showed high level of resistance to stripe rust (Puccinia striiformis f. sp. tritici, Pst) pathogens prevalent in China, including V26/Gui 22. These new hexaploid triticales not only enhanced diversification of triticale but also could be utilized as valuable germplasm for wheat improvement. PMID:27182983

  10. Transcriptional profiling in response to terminal drought stress reveals differential responses along the wheat genome

    PubMed Central

    Aprile, Alessio; Mastrangelo, Anna M; De Leonardis, Anna M; Galiba, Gabor; Roncaglia, Enrica; Ferrari, Francesco; De Bellis, Luigi; Turchi, Luana; Giuliano, Giovanni; Cattivelli, Luigi

    2009-01-01

    Background Water stress during grain filling has a marked effect on grain yield, leading to a reduced endosperm cell number and thus sink capacity to accumulate dry matter. The bread wheat cultivar Chinese Spring (CS), a Chinese Spring terminal deletion line (CS_5AL-10) and the durum wheat cultivar Creso were subjected to transcriptional profiling after exposure to mild and severe drought stress at the grain filling stage to find evidences of differential stress responses associated to different wheat genome regions. Results The transcriptome analysis of Creso, CS and its deletion line revealed 8,552 non redundant probe sets with different expression levels, mainly due to the comparisons between the two species. The drought treatments modified the expression of 3,056 probe sets. Besides a set of genes showing a similar drought response in Creso and CS, cluster analysis revealed several drought response features that can be associated to the different genomic structure of Creso, CS and CS_5AL-10. Some drought-related genes were expressed at lower level (or not expressed) in Creso (which lacks the D genome) or in the CS_5AL-10 deletion line compared to CS. The chromosome location of a set of these genes was confirmed by PCR-based mapping on the D genome (or the 5AL-10 region). Many clusters were characterized by different level of expression in Creso, CS and CS_AL-10, suggesting that the different genome organization of the three genotypes may affect plant adaptation to stress. Clusters with similar expression trend were grouped and functional classified to mine the biological mean of their activation or repression. Genes involved in ABA, proline, glycine-betaine and sorbitol pathways were found up-regulated by drought stress. Furthermore, the enhanced expression of a set of transposons and retrotransposons was detected in CS_5AL-10. Conclusion Bread and durum wheat genotypes were characterized by a different physiological reaction to water stress and by a

  11. WheatGenome.info: A Resource for Wheat Genomics Resource.

    PubMed

    Lai, Kaitao

    2016-01-01

    An integrated database with a variety of Web-based systems named WheatGenome.info hosting wheat genome and genomic data has been developed to support wheat research and crop improvement. The resource includes multiple Web-based applications, which are implemented as a variety of Web-based systems. These include a GBrowse2-based wheat genome viewer with BLAST search portal, TAGdb for searching wheat second generation genome sequence data, wheat autoSNPdb, links to wheat genetic maps using CMap and CMap3D, and a wheat genome Wiki to allow interaction between diverse wheat genome sequencing activities. This portal provides links to a variety of wheat genome resources hosted at other research organizations. This integrated database aims to accelerate wheat genome research and is freely accessible via the web interface at http://www.wheatgenome.info/ . PMID:26519407

  12. Genetic diversity for grain nutrients in wild emmer wheat: potential for wheat improvement

    PubMed Central

    Chatzav, Merav; Peleg, Zvi; Ozturk, Levent; Yazici, Atilla; Fahima, Tzion; Cakmak, Ismail; Saranga, Yehoshua

    2010-01-01

    Background and Aims Micronutrient malnutrition, particularly zinc and iron deficiency, afflicts over three billion people worldwide due to low dietary intake. In the current study, wild emmer wheat (Triticum turgidum ssp. dicoccoides), the progenitor of domesticated wheat, was tested for (1) genetic diversity in grain nutrient concentrations, (2) associations among grain nutrients and their relationships with plant productivity, and (3) the association of grain nutrients with the eco-geographical origin of wild emmer accessions. Methods A total of 154 genotypes, including wild emmer accessions from across the Near Eastern Fertile Crescent and diverse wheat cultivars, were characterized in this 2-year field study for grain protein, micronutrient (zinc, iron, copper and manganese) and macronutrient (calcium, magnesium, potassium, phosphorus and sulphur) concentrations. Key Results Wide genetic diversity was found among the wild emmer accessions for all grain nutrients. The concentrations of grain zinc, iron and protein in wild accessions were about two-fold greater than in the domesticated genotypes. Concentrations of these compounds were positively correlated with one another, with no clear association with plant productivity, suggesting that all three nutrients can be improved concurrently with no yield penalty. A subset of 12 populations revealed significant genetic variation between and within populations for all minerals. Association between soil characteristics at the site of collection and grain nutrient concentrations showed negative associations between soil clay content and grain protein and between soil-extractable zinc and grain zinc, the latter suggesting that the greatest potential for grain nutrient minerals lies in populations from micronutrient-deficient soils. Conclusions Wild emmer wheat germplasm offers unique opportunities to exploit favourable alleles for grain nutrient properties that were excluded from the domesticated wheat gene pool. PMID

  13. Structure and expression analysis of genes encoding ADP-glucose pyrophosphorylase large subunit in wheat and its relatives.

    PubMed

    Zhang, Xiao-Wei; Li, Si-Yu; Zhang, Ling-Ling; Yang, Qiang; Jiang, Qian-Tao; Ma, Jian; Qi, Peng-Fei; Li, Wei; Chen, Guo-Yue; Lan, Xiu-Jin; Deng, Mei; Lu, Zhen-Xiang; Liu, Chunji; Wei, Yu-Ming; Zheng, You-Liang

    2016-07-01

    ADP-glucose pyrophosphorylase (AGP), which consists of two large subunits (AGP-L) and two small subunits (AGP-S), controls the rate-limiting step in the starch biosynthetic pathway. In this study, a full-length open reading frame (ORF) of AGP-L gene (named as Agp2) in wheat and a series of Agp2 gene sequences in wheat relatives were isolated. The coding region of Agp2 contained 15 exons and 14 introns including a full-length ORF of 1566 nucleotides, and the deduced protein contained 522 amino acids (57.8 kDa). Generally, the phylogenetic tree of Agp2 indicated that sequences from A- and D-genome donor species were most similar to each other and sequences from B-genome donor species contained more variation. Starch accumulation and Agp2 expression in wheat grains reached their peak at 21 and 15 days post anthesis (DPA), respectively. PMID:27299732

  14. PROGENITORS OF RECOMBINING SUPERNOVA REMNANTS

    SciTech Connect

    Moriya, Takashi J.

    2012-05-01

    Usual supernova remnants have either ionizing plasma or plasma in collisional ionization equilibrium, i.e., the ionization temperature is lower than or equal to the electron temperature. However, the existence of recombining supernova remnants, i.e., supernova remnants with ionization temperature higher than the electron temperature, has been recently confirmed. One suggested way to have recombining plasma in a supernova remnant is to have a dense circumstellar medium at the time of the supernova explosion. If the circumstellar medium is dense enough, collisional ionization equilibrium can be established in the early stage of the evolution of the supernova remnant and subsequent adiabatic cooling, which occurs after the shock wave gets out of the dense circumstellar medium, makes the electron temperature lower than the ionization temperature. We study the circumstellar medium around several supernova progenitors and show which supernova progenitors can have a circumstellar medium dense enough to establish collisional ionization equilibrium soon after the explosion. We find that the circumstellar medium around red supergiants (especially massive ones) and the circumstellar medium dense enough to make Type IIn supernovae can establish collisional ionization equilibrium soon after the explosion and can evolve to become recombining supernova remnants. Wolf-Rayet stars and white dwarfs have the possibility to be recombining supernova remnants but the fraction is expected to be very small. As the occurrence rate of the explosions of red supergiants is much higher than that of Type IIn supernovae, the major progenitors of recombining supernova remnants are likely to be red supergiants.

  15. Wheat Quality Council Hard Spring Wheat Technical Committee 2010 Crop

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Breeders’ experimental lines of wheat are evaluated for overall quality before being released for commercial production. The Hard Spring Wheat Technical Committee provides milling and baking quality data on breeders’ experimental lines of wheat that are annually submitted to the Wheat Quality Counc...

  16. Molecular analysis, cytogenetics and fertility of introgression lines from transgenic wheat to Aegilops cylindrica host.

    PubMed

    Schoenenberger, Nicola; Guadagnuolo, Roberto; Savova-Bianchi, Dessislava; Küpfer, Philippe; Felber, François

    2006-12-01

    Natural hybridization and backcrossing between Aegilops cylindrica and Triticum aestivum can lead to introgression of wheat DNA into the wild species. Hybrids between Ae. cylindrica and wheat lines bearing herbicide resistance (bar), reporter (gus), fungal disease resistance (kp4), and increased insect tolerance (gna) transgenes were produced by pollination of emasculated Ae. cylindrica plants. F1 hybrids were backcrossed to Ae. cylindrica under open-pollination conditions, and first backcrosses were selfed using pollen bags. Female fertility of F1 ranged from 0.03 to 0.6%. Eighteen percent of the sown BC1s germinated and flowered. Chromosome numbers ranged from 30 to 84 and several of the plants bore wheat-specific sequence-characterized amplified regions (SCARs) and the bar gene. Self fertility in two BC1 plants was 0.16 and 5.21%, and the others were completely self-sterile. Among 19 BC1S1 individuals one plant was transgenic, had 43 chromosomes, contained the bar gene, and survived glufosinate treatments. The other BC1S1 plants had between 28 and 31 chromosomes, and several of them carried SCARs specific to wheat A and D genomes. Fertility of these plants was higher under open-pollination conditions than by selfing and did not necessarily correlate with even or euploid chromosome number. Some individuals having supernumerary wheat chromosomes recovered full fertility. PMID:17028347

  17. De Novo Sequencing and Characterization of the Transcriptome of Dwarf Polish Wheat (Triticum polonicum L.)

    PubMed Central

    Wang, Chao; Wang, Xiaolu; Peng, Fan; Wang, Ruijiao; Jiang, Yulin; Zeng, Jian; Fan, Xing; Kang, Houyang; Sha, Lina; Zhang, Haiqin; Xiao, Xue

    2016-01-01

    Construction as well as characterization of a polish wheat transcriptome is a crucial step to study useful traits of polish wheat. In this study, a transcriptome, including 76,014 unigenes, was assembled from dwarf polish wheat (DPW) roots, stems, and leaves using the software of Trinity. Among these unigenes, 61,748 (81.23%) unigenes were functionally annotated in public databases and classified into differentially functional types. Aligning this transcriptome against draft wheat genome released by the International Wheat Genome Sequencing Consortium (IWGSC), 57,331 (75.42%) unigenes, including 26,122 AB-specific and 2,622 D-specific unigenes, were mapped on A, B, and/or D genomes. Compared with the transcriptome of T. turgidum, 56,343 unigenes were matched with 103,327 unigenes of T. turgidum. Compared with the genomes of rice and barley, 14,404 and 7,007 unigenes were matched with 14,608 genes of barley and 7,708 genes of rice, respectively. On the other hand, 2,148, 1,611, and 2,707 unigenes were expressed specifically in roots, stems, and leaves, respectively. Finally, 5,531 SSR sequences were observed from 4,531 unigenes, and 518 primer pairs were designed. PMID:27429972

  18. 21 CFR 137.195 - Crushed wheat.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Crushed wheat. 137.195 Section 137.195 Food and... Related Products § 137.195 Crushed wheat. Crushed wheat, coarse ground wheat, is the food prepared by so crushing cleaned wheat other than durum wheat and red durum wheat that, when tested by the...

  19. 21 CFR 137.195 - Crushed wheat.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Crushed wheat. 137.195 Section 137.195 Food and... Related Products § 137.195 Crushed wheat. Crushed wheat, coarse ground wheat, is the food prepared by so crushing cleaned wheat other than durum wheat and red durum wheat that, when tested by the...

  20. 21 CFR 137.195 - Crushed wheat.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Crushed wheat. 137.195 Section 137.195 Food and... Related Products § 137.195 Crushed wheat. Crushed wheat, coarse ground wheat, is the food prepared by so crushing cleaned wheat other than durum wheat and red durum wheat that, when tested by the...

  1. 21 CFR 137.195 - Crushed wheat.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Crushed wheat. 137.195 Section 137.195 Food and... Related Products § 137.195 Crushed wheat. Crushed wheat, coarse ground wheat, is the food prepared by so crushing cleaned wheat other than durum wheat and red durum wheat that, when tested by the...

  2. Introgression of an imidazolinone-resistance gene from winter wheat (Triticum aestivum L.) into jointed goatgrass (Aegilops cylindrica Host).

    PubMed

    Perez-Jones, Alejandro; Mallory-Smith, Carol A; Hansen, Jennifer L; Zemetra, Robert S

    2006-12-01

    Imidazolinone-resistant winter wheat (Triticum aestivum L.) is being commercialized in the USA. This technology allows wheat growers to selectively control jointed goatgrass (Aegilops cylindrica Host), a weed that is especially problematic because of its close genetic relationship with wheat. However, the potential movement of the imidazolinone-resistance gene from winter wheat to jointed goatgrass is a concern. Winter wheat and jointed goatgrass have the D genome in common and can hybridize and backcross under natural field conditions. Since the imidazolinone-resistance gene (Imi1) is located on the D genome, it is possible for resistance to be transferred to jointed goatgrass via hybridization and backcrossing. To study the potential for gene movement, BC(2)S(2) plants were produced artificially using imidazolinone-resistant winter wheat (cv. FS-4) as the female parent and a native jointed goatgrass collection as the male recurrent parent. FS-4, the jointed goatgrass collection, and 18 randomly selected BC(2)S(2) populations were treated with imazamox. The percentage of survival was 100% for the FS-4, 0% for the jointed goatgrass collection and 6 BC(2)S(2) populations, 40% or less for 2 BC(2)S(2) populations, and 50% or greater for the remaining 10 BC(2)S(2) populations. Chromosome counts in BC(2)S(3) plants showed a restoration of the chromosome number of jointed goatgrass, with four out of four plants examined having 28 chromosomes. Sequencing of AHASL1D in BC(2)S(3) plants derived from BC(2)S(2)-6 revealed the sexual transmission of Imi1 from FS-4 to jointed goatgrass. Imi1 conferred resistance to the imidazolinone herbicide imazamox, as shown by the in vitro assay for acetohydroxyacid synthase (AHAS) activity. PMID:17058103

  3. Registration of 'Antero' Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ’Antero’ (Reg. No. CV-XXXX, PI 667743) hard white winter wheat (Triticum aestivum L.) was developed by the Colorado Agricultural Experiment Station and released in August 2012 through a marketing agreement with the Colorado Wheat Research Foundation. In addition to researchers at Colorado State Univ...

  4. Agrometeorology and Wheat Production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Winter wheat phenology varies among shoots on the plant to main stems on plants within a plot to locations across a landscape. Most often phenological measurements have focused on small treatment plots under presumably similar soils and topography. Many models exist to predict wheat phenology for sm...

  5. Registration of 'Ripper' Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Ripper’ (Reg. No. CV-1016, PI 644222) hard red winter wheat (Triticum aestivum L.) was developed by the Colorado Agricultural Experiment Station and released in August 2006 through an exclusive marketing agreement with the Colorado Wheat Research Foundation. In addition to researchers at Colorado S...

  6. Registration of 'Snowmass' wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Snowmass’ (Reg. No. CV-1050, PI 658597) hard white winter wheat (Triticum aestivum L.) was developed by the Colorado Agricultural Experiment Station and released in July 2009 through a marketing agreement with the Colorado Wheat Research Foundation. In addition to researchers at Colorado State Uni...

  7. Registration of 'Okfield' wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'Okfield' (Reg. No. CV-_______, PI 643087) is a hard red winter (HRW) wheat (Triticum aestivum L.) cultivar developed and released cooperatively by the Oklahoma Agric. Exp. Stn. (AES) and the USDA-ARS in 2005. It is recommended for dryland wheat production using either grain-only and dual-purpose m...

  8. Wheat: Science and Trade

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Up-to-date textbooks are needed to educate the agricultural scientists of tomorrow. This manuscript comprises one chapter in such a textbook, “Wheat: Science and Trade”, and covers the subject of wheat genetic engineering. The chapter begins with a summary of key discussion elements and ends with a...

  9. Registration of 'Denali' wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'Denali' (PI 664256) hard red winter wheat (Triticum aestivum L.) was developed by the Colorado Agricultural Experiment Station and released cooperatively by Colorado State University (CSU) and Kansas State University (KSU) August, 2011, through a marketing agreement with the Colorado Wheat Research...

  10. Registration of 'Byrd' wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'Byrd' (PI 664257) hard red winter wheat (Triticum aestivum L.) was developed by the Colorado Agricultural Experiment Station and released August, 2011, through a marketing agreement with the Colorado Wheat Research Foundation. In addition to researchers at Colorado State University (CSU), USDA-ARS ...

  11. Length variations of i-type low-molecular-weight glutenin subunit genes in diploid wheats.

    PubMed

    Long, H; Huang, Z; Wei, Y-M; Yan, Z-H; Ma, Z-C; Zheng, Y-L

    2008-04-01

    Allelic variation of the low-molecular-weight glutenin subunit (LMW-GS) is associated with the significant differences of dough quality in bread and durum wheat, and has been widely evaluated at protein level in wheat and its relatives. In this study, a PCR primer set, targeting the high variable repetitive domains, was employed to assay the length variation of i-type LMW-GS genes in the A-genomes of diploid wheats, the diploid progenitors of tetraploid and hexaploid wheat. A total of 71 accessions of diploid wheats, belonging to two wild and one cultivated species, were investigated. The higher variations of repetitive length in i-type LMW-GS genes were found in diploid wheats with Nei's genetic variation index (H) of 0.834. The two wild species, T. boeoticum and T. urartu, were found to possess the similar degree of variability, with the Nei's genetic variation index of 0.806 and 0.783, respectively. Less variations were detected in T. monococcum (H = 0.680), a cultivated species domesticated from T. boeoticum. The sufficient variations found in this study could be used as valuable sources for the enrichment of the genetic variations and the alteration of flour-processing properties of the cultivated wheat. To our knowledge, it was the first time that an analysis of length variation targeting a particular group of genes of LMW-GS complex multigene families was conducted. PMID:18666554

  12. Implication of Triticum searsii as the B-genome donor to wheat using DNA hybridizations.

    PubMed

    Nath, J; McNay, J W; Paroda, C M; Gulati, S C

    1983-08-01

    In vitro DNA:DNA hybridizations and hydroxyapatite thermal chromatography were employed to help identify the species ancestral to the B genome of the polyploid wheats. We hybridized 3H-Triticum aestivum DNA to the unlabeled DNAs of T. urartu, T. speltoides, T. sharonensis, T. bicorne, T. longissimum, and T. searsii, 3H-Labeled DNA of T. urartu was hybridized with the DNA of a synthetic tetraploid. AADD. The heteroduplex thermal stabilities indicated that T. searsii was most closely related to T. aestivum (ABD) and that the genome of T. urartu was more closely related to the A genome than the B genome. The degree of reassociation which may have occurred between the six diploid species and the D genome of T. aestivum was evaluated by hybridizing 3H-T. tauschii DNA with the DNAs of the diploids. The results indicated that T. urartu had the least sequence homology to T. tauschii, the D-genome donor lending additional support to the conclusion that T. urartu is related to the A genome. Thus, it is highly probable that T. searsii is the B-genome donor to the polyploid wheats or a major chromosome donor if the B genome is, in fact, polyphyletic in origin. PMID:6626143

  13. Genetic Diversity, Population Structure, and Linkage Disequilibrium in Bread Wheat (Triticum aestivum L.).

    PubMed

    Tascioglu, Tulin; Metin, Ozge Karakas; Aydin, Yildiz; Sakiroglu, Muhammet; Akan, Kadir; Uncuoglu, Ahu Altinkut

    2016-08-01

    Bread wheat (Triticum aestivum L.) gene pool was analyzed with 117 microsatellite markers scattered throughout A, B, and D genomes. Ninety microsatellite markers were giving 1620 polymorphic alleles in 55 different bread wheat genotypes. These genotypes were found to be divided into three subgroups based on Bayesian model and Principal component analysis. The highest polymorphism information content value for the markers resides on A genome was estimated for wmc262 marker located on 4A chromosome with the polymorphism information content value of 0.960. The highest polymorphism information content value (0.954) among the markers known to be located on B genome was realized for wmc44 marker located on 1B chromosome. The highest polymorphism information content value for the markers specific to D genome was found in gwm174 marker located on 5D chromosome with the polymorphism information content value of 0.948. The presence of linkage disequilibrium between 81 pairwise SSR markers reside on the same chromosome was tested and very limited linkage disequilibrium was observed. The results confirmed that the most distant genotype pairs were as follows Ceyhan-99-Behoth 6, Gerek 79-Douma 40989, and Karahan-99-Douma 48114. PMID:27048293

  14. Evolution of physiological responses to salt stress in hexaploid wheat

    PubMed Central

    Yang, Chunwu; Zhao, Long; Zhang, Huakun; Yang, Zongze; Wang, Huan; Wen, Shanshan; Zhang, Chunyu; Rustgi, Sachin; von Wettstein, Diter; Liu, Bao

    2014-01-01

    Hexaploid bread wheat (Triticum aestivum L., genome BBAADD) is generally more salt tolerant than its tetraploid wheat progenitor (Triticum turgidum L.). However, little is known about the physiological basis of this trait or about the relative contributions of allohexaploidization and subsequent evolutionary genetic changes on the trait development. Here, we compared the salt tolerance of a synthetic allohexaploid wheat (neo-6x) with its tetraploid (T. turgidum; BBAA) and diploid (Aegilops tauschii; DD) parents, as well as a natural hexaploid bread wheat (nat-6x). We studied 92 morphophysiological traits and analyzed homeologous gene expression of a major salt-tolerance gene High-Affinity K+ Transporter 1;5 (HKT1;5). We observed that under salt stress, neo-6x exhibited higher fitness than both of its parental genotypes due to inheritance of favorable traits like higher germination rate from the 4x parent and the stronger root Na+ retention capacity from the 2x parent. Moreover, expression of the D-subgenome HKT1;5 homeolog, which is responsible for Na+ removal from the xylem vessels, showed an immediate transcriptional reprogramming following allohexaploidization, i.e., from constitutive high basal expression in Ae. tauschii (2x) to salt-induced expression in neo-6x. This phenomenon was also witnessed in the nat-6x. An integrated analysis of 92 traits showed that, under salt-stress conditions, neo-6x resembled more closely the 2x than the 4x parent, suggesting that the salt stress induces enhanced expressivity of the D-subgenome homeologs in the synthetic hexaploid wheat. Collectively, the results suggest that condition-dependent functionalization of the subgenomes might have contributed to the wide-ranging adaptability of natural hexaploid wheat. PMID:25074914

  15. Evolution of physiological responses to salt stress in hexaploid wheat.

    PubMed

    Yang, Chunwu; Zhao, Long; Zhang, Huakun; Yang, Zongze; Wang, Huan; Wen, Shanshan; Zhang, Chunyu; Rustgi, Sachin; von Wettstein, Diter; Liu, Bao

    2014-08-12

    Hexaploid bread wheat (Triticum aestivum L., genome BBAADD) is generally more salt tolerant than its tetraploid wheat progenitor (Triticum turgidum L.). However, little is known about the physiological basis of this trait or about the relative contributions of allohexaploidization and subsequent evolutionary genetic changes on the trait development. Here, we compared the salt tolerance of a synthetic allohexaploid wheat (neo-6x) with its tetraploid (T. turgidum; BBAA) and diploid (Aegilops tauschii; DD) parents, as well as a natural hexaploid bread wheat (nat-6x). We studied 92 morphophysiological traits and analyzed homeologous gene expression of a major salt-tolerance gene High-Affinity K(+) Transporter 1;5 (HKT1;5). We observed that under salt stress, neo-6x exhibited higher fitness than both of its parental genotypes due to inheritance of favorable traits like higher germination rate from the 4x parent and the stronger root Na(+) retention capacity from the 2x parent. Moreover, expression of the D-subgenome HKT1;5 homeolog, which is responsible for Na(+) removal from the xylem vessels, showed an immediate transcriptional reprogramming following allohexaploidization, i.e., from constitutive high basal expression in Ae. tauschii (2x) to salt-induced expression in neo-6x. This phenomenon was also witnessed in the nat-6x. An integrated analysis of 92 traits showed that, under salt-stress conditions, neo-6x resembled more closely the 2x than the 4x parent, suggesting that the salt stress induces enhanced expressivity of the D-subgenome homeologs in the synthetic hexaploid wheat. Collectively, the results suggest that condition-dependent functionalization of the subgenomes might have contributed to the wide-ranging adaptability of natural hexaploid wheat. PMID:25074914

  16. Argentina wheat yield model

    NASA Technical Reports Server (NTRS)

    Callis, S. L.; Sakamoto, C.

    1984-01-01

    Five models based on multiple regression were developed to estimate wheat yields for the five wheat growing provinces of Argentina. Meteorological data sets were obtained for each province by averaging data for stations within each province. Predictor variables for the models were derived from monthly total precipitation, average monthly mean temperature, and average monthly maximum temperature. Buenos Aires was the only province for which a trend variable was included because of increasing trend in yield due to technology from 1950 to 1963.

  17. Sequencing chromosome 5D of Aegilops tauschii and comparison with its allopolyploid descendant bread wheat (Triticum aestivum).

    PubMed

    Akpinar, Bala A; Lucas, Stuart J; Vrána, Jan; Doležel, Jaroslav; Budak, Hikmet

    2015-08-01

    Flow cytometric sorting of individual chromosomes and chromosome-based sequencing reduces the complexity of large, repetitive Triticeae genomes. We flow-sorted chromosome 5D of Aegilops tauschii, the D genome donor of bread wheat and sequenced it by Roche 454 GS FLX platform to approximately 2.2x coverage. Repetitive sequences represent 81.09% of the survey sequences of this chromosome, and Class I retroelements are the prominent type, with a particular abundance of LTR/Gypsy superfamily. Nonrepetitive sequences were assembled to cover 17.76% of the total chromosome regions. Up to 6188 nonrepetitive gene loci were predicted to be encoded by the 5D chromosome. The numbers and chromosomal distribution patterns of tRNA genes suggest abundance in tRNA(L) (ys) and tRNA(M) (et) species, while the nonrepetitive assembly reveals tRNA(A) (la) species as the most abundant type. A comparative analysis of the genomic sequences of bread wheat and Aegilops chromosome 5D indicates conservation of gene content. Orthologous unique genes, matching Aegilops 5D sequences, numbered 3730 in barley, 5063 in Brachypodium, 4872 in sorghum and 4209 in rice. In this study, we provide a chromosome-specific view into the structure and organization of the 5D chromosome of Ae. tauschii, the D genome ancestor of bread wheat. This study contributes to our understanding of the chromosome-level evolution of the wheat genome and presents a valuable resource in wheat genomics due to the recent hybridization of Ae. tauschii genome with its tetraploid ancestor. PMID:25516153

  18. Wheat for Kids! [and] Teacher's Guide.

    ERIC Educational Resources Information Center

    Idaho Wheat Commission, Boise.

    "Wheat for Kids" contains information at the elementary school level about: the structure of the wheat kernel; varieties of wheat and their uses; growing wheat; making wheat dough; the U.S. Department of Agriculture Food Guide Pyramid and nutrition; Idaho's part of the international wheat market; recipes; and word games based on the information…

  19. 21 CFR 137.190 - Cracked wheat.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Cracked wheat. 137.190 Section 137.190 Food and... Related Products § 137.190 Cracked wheat. Cracked wheat is the food prepared by so cracking or cutting into angular fragments cleaned wheat other than durum wheat and red durum wheat that, when tested...

  20. 21 CFR 184.1322 - Wheat gluten.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Wheat gluten. 184.1322 Section 184.1322 Food and....1322 Wheat gluten. (a) Wheat gluten (CAS Reg. No. 8002-80-0) is the principal protein component of wheat and consists mainly of gliadin and glutenin. Wheat gluten is obtained by hydrating wheat flour...

  1. 21 CFR 137.190 - Cracked wheat.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Cracked wheat. 137.190 Section 137.190 Food and... Related Products § 137.190 Cracked wheat. Cracked wheat is the food prepared by so cracking or cutting into angular fragments cleaned wheat other than durum wheat and red durum wheat that, when tested...

  2. 21 CFR 137.190 - Cracked wheat.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Cracked wheat. 137.190 Section 137.190 Food and... Related Products § 137.190 Cracked wheat. Cracked wheat is the food prepared by so cracking or cutting into angular fragments cleaned wheat other than durum wheat and red durum wheat that, when tested...

  3. 21 CFR 137.190 - Cracked wheat.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Cracked wheat. 137.190 Section 137.190 Food and... Related Products § 137.190 Cracked wheat. Cracked wheat is the food prepared by so cracking or cutting into angular fragments cleaned wheat other than durum wheat and red durum wheat that, when tested...

  4. Visualization, analysis, and design of COMBO-FISH probes in the grid-based GLOBE 3D genome platform.

    PubMed

    Kepper, Nick; Schmitt, Eberhard; Lesnussa, Michael; Weiland, Yanina; Eussen, Hubert B; Grosveld, Frank G; Hausmann, Michael; Knoch, Tobias A

    2010-01-01

    The genome architecture in cell nuclei plays an important role in modern microscopy for the monitoring of medical diagnosis and therapy since changes of function and dynamics of genes are interlinked with changing geometrical parameters. The planning of corresponding diagnostic experiments and their imaging is a complex and often interactive IT intensive challenge and thus makes high-performance grids a necessity. To detect genetic changes we recently developed a new form of fluorescence in situ hybridization (FISH) - COMBinatorial Oligonucleotide FISH (COMBO-FISH) - which labels small nucleotide sequences clustering at a desired genomic location. To achieve a unique hybridization spot other side clusters have to be excluded. Therefore, we have designed an interactive pipeline using the grid-based GLOBE 3D Genome Viewer and Platform to design and display different labelling variants of candidate probe sets. Thus, we have created a grid-based virtual "paper" tool for easy interactive calculation, analysis, management, and representation for COMBO-FISH probe design with many an advantage: Since all the calculations and analysis run in a grid, one can instantly and with great visual ease locate duplications of gene subsequences to guide the elimination of side clustering sequences during the probe design process, as well as get at least an impression of the 3D architectural embedding of the respective chromosome region, which is of major importance to estimate the hybridization probe dynamics. Beyond, even several people at different locations could work on the same process in a team wise manner. Consequently, we present how a complex interactive process can profit from grid infrastructure technology using our unique GLOBE 3D Genome Platform gateway towards a real interactive curative diagnosis planning and therapy monitoring. PMID:20543436

  5. NADP-dependent aromatic alcohol dehydrogenase in polyploid wheats and their diploid relatives. On the origin and phylogeny of polyploid wheats.

    PubMed

    Jaaska, V

    1978-09-01

    The three major isoenzymes of the NADP-dependent aromatic alcohol dehydrogenase (ADH-B), distinguished in polyploid wheats by means of polyacrylamide gel electrophoresis, are shown to be coded by homoeoalleles of the locus Adh-2 on short arms of chromosomes of the fifth homoeologous group. Essentially codominant expression of the Adh-2 homoeolleles of composite genomes was observed in young seedlings of hexaploid wheats (T. aestivum s.l.) and tetraploid wheats of the emmer group (T. turgidum s.l.), whereas only the isoenzyme characteristic of the A genome is present in the seedlings of the timopheevii-group tetraploids (T. timopheevii s.str. and T. araraticum).The slowest-moving B(3) isoenzyme of polyploid wheats, coded by the homoeoallele of the B genome, is characteristic of the diploid species Aegilops speltoides S.l., including both its awned and awnless forms, but was not encountered in Ae. bicornis, Ae. sharonensis and Ae. longissima. The last two diploids, as well as Ae. tauschii, Ae. caudata, Triticum monococcum s.str., T. boeoticum s.l. (incl. T. thaoudar) and T. urartu all shared a common isoenzyme coinciding electrophoretically with the band B(2) controlled by the A and D genome homoeoalleles in polyploid wheats. Ae. bicomis is characterized by the slowest isoenzyme, B(4), not found in wheats and in the other diploid Aegilops species studied.Two electrophoretic variants of ADH-B, B(1) and B(2), considered to be alloenzymes of the A genome homoeoallele, were observed in T. dicoccoides, T. dicoccon, T. turgidum. s.str. and T. spelta, whereas B(2) was characteristic of T. timopheevii s.l. and only B(1) was found in the remaining taxa of polyploid wheats. The isoenzyme B(1), not encountered among diploid species, is considered to be a mutational derivative which arose on the tetraploid level from its more ancestral form B(2) characteristic of diploid wheats.The implication of the ADH-B isoenzyme data to the problems of wheat phylogeny and gene evolution is

  6. The progenitors of stripped-envelope supernovae

    NASA Astrophysics Data System (ADS)

    Elias-Rosa, N.

    2013-05-01

    The type Ib/c SNe are those explosions which come from massive star populations, but lack hydrogen and helium. These have been proposed to originate in the explosions of massive Wolf-Rayet stars, and we should easily be able to detect the very luminous, young progenitors if they exist. However, there has not been any detection of progenitors so far. I present the study of two extinguished Type Ic SNe 2003jg and 2004cc. In both cases there is no clear evidence of a direct detection of their progenitors in deep pre-explosion images. Upper limits derived by inserting artificial stars of known brightness at random positions around the progenitor positions (M_v>-8.8 and M_v>-9 magnitudes for the progenitors of SN 2003jg and SN 2004cc, respectively) are brighter than those expected for a massive WC (Wolf-Rayet, carbon-rich) or WO (Wolf-Rayet, oxygen-rich) (e.g., approximately between -3 and -6 in the LMC). Therefore, this is perhaps further evidence that the most massive stars may give rise to black-holes forming SNe, or it is an undetected, compact massive star hidden by a thick dust lane. However the extinction toward these SNe is currently one of the largest known. Even if these results do not directly reveal the nature of the type Ic SN progenitors, they can help to characterize the dusty environment which surrounded the progenitor of the stripped-envelope CC-SNe.

  7. Biofortification of wheat grain with iron and zinc: integrating novel genomic resources and knowledge from model crops

    PubMed Central

    Borrill, Philippa; Connorton, James M.; Balk, Janneke; Miller, Anthony J.; Sanders, Dale; Uauy, Cristobal

    2014-01-01

    Wheat, like many other staple cereals, contains low levels of the essential micronutrients iron and zinc. Up to two billion people worldwide suffer from iron and zinc deficiencies, particularly in regions with predominantly cereal-based diets. Although wheat flour is commonly fortified during processing, an attractive and more sustainable solution is biofortification, which requires developing new varieties of wheat with inherently higher iron and zinc content in their grains. Until now most studies aimed at increasing iron and zinc content in wheat grains have focused on discovering natural variation in progenitor or related species. However, recent developments in genomics and transformation have led to a step change in targeted research on wheat at a molecular level. We discuss promising approaches to improve iron and zinc content in wheat using knowledge gained in model grasses. We explore how the latest resources developed in wheat, including sequenced genomes and mutant populations, can be exploited for biofortification. We also highlight the key research and practical challenges that remain in improving iron and zinc content in wheat. PMID:24600464

  8. Wheat Quality Council, Hard Spring Wheat Technical Committee, 2014 Crop

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Eleven experimental lines of hard spring wheat were grown at up to five locations in 2014 and evaluated for kernel, milling, and bread baking quality against the check variety Glenn. Wheat samples were submitted through the Wheat Quality Council and processed and milled at the USDA-ARS Hard Red Spr...

  9. Insects which challenge global wheat production: Russian wheat aphid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The book chapter on Russian wheat aphid, (Diuraphis noxia (Mord.)), is one of several that addresses significant pests in the book entitled, Wheat Science and Trade. The chapter gives a detailed account of the history of the Russian wheat aphid as global pest, and its biology, ecology and managemen...

  10. Chromosome assignment of four photosynthesis-related genes and their variability in wheat species.

    PubMed

    Ogihara, Y; Shimizu, H; Hasegawa, K; Tsujimoto, H; Sasakuma, T

    1994-06-01

    Copy numbers of four photosynthesis-related genes, PhyA, Ppc, RbcS and Lhcb1 (*)1, in wheat genomes were estimated by slot-blot analysis, and these genes were assigned to the chromosome arms of common wheat by Southern hybridization of DNA from an aneuploid series of the cultivar Chinese Spring. The copy number of PhyA was estimated to be one locus per haploid genome, and this gene was assigned to chromosomes 4AL, 4BS and 4DS. The Ppc gene showed a low copy number of small multigenes, and was located on the short arm of homoeologous group 3 chromosomes and the long arm of chromosomes of homoeologous group 7. RbcS consisted of a multigene family, with approximately 100 copies in the common wheat genome, and was located on the short arm of group 2 chromosomes and the long arm of group 5 chromosomes. Lhcb1 (*)1 also consisted of a multigene family with about 50 copies in common wheat. Only a limited number of restriction fragments (approximately 15%) were used to determine the locations of members of this family on the long arm of group 1 chromosomes owing to the multiplicity of DNA bands. The variability of hybridized bands with the four genes was less in polyploids, but was more in the case of multigene families. RFLP analysis of polyploid wheats and their presumed ancestors was carried out with probes of the oat PhyA gene, the maize Ppc gene, the wheat RbcS gene and the wheat Lhcb1 (*)1 gene. The RFLP patterns of common wheat most closely resembled those of T. Dicoccum (Emmer wheat), T. urartu (A genome), Ae. speltoides (S genome) and Ae. squarrosa (D genome). Diversification of genes in the wheat complex appear to have occurred mainly at the diploid level. Based on RFLP patterns, B and S genomes were clustered into two major groups. The fragment numbers per genome were reduced in proportion to the increase of ploidy level for all four genes, suggesting that some mechanism(s) might operate to restrict, and so keep to a minimum, the gene numbers in the polyploid

  11. Progenitor's Signatures in Type Ia Supernova Remnants

    NASA Astrophysics Data System (ADS)

    Chiotellis, A.; Kosenko, D.; Schure, K. M.; Vink, J.

    2013-01-01

    The remnants of Type Ia supernovae (SNe Ia) can provide important clues about their progenitor histories. We discuss two well-observed supernova remnants (SNRs) that are believed to have resulted from SNe Ia, and use various tools to shed light on the possible progenitor histories. We find that Kepler's SNR is consistent with a symbiotic binary progenitor consisting of a white dwarf and an AGB star. Our hydrosimulations can reproduce the observed kinematic and morphological properties. For Tycho's remnant we use the characteristics of the X-ray spectrum and kinematics to show that the ejecta has likely interacted with dense circumstellar gas.

  12. Progenitor genealogy in the developing cerebral cortex.

    PubMed

    Laguesse, Sophie; Peyre, Elise; Nguyen, Laurent

    2015-01-01

    The mammalian cerebral cortex is characterized by a complex histological organization that reflects the spatio-temporal stratifications of related stem and neural progenitor cells, which are responsible for the generation of distinct glial and neuronal subtypes during development. Some work has been done to shed light on the existing filiations between these progenitors as well as their respective contribution to cortical neurogenesis. The aim of the present review is to summarize the current views of progenitor hierarchy and relationship in the developing cortex and to further discuss future research directions that would help us to understand the molecular and cellular regulating mechanisms involved in cerebral corticogenesis. PMID:25141969

  13. Lr34 multi-pathogen resistance ABC transporter: molecular analysis of homoeologous and orthologous genes in hexaploid wheat and other grass species.

    PubMed

    Krattinger, Simon G; Lagudah, Evans S; Wicker, Thomas; Risk, Joanna M; Ashton, Anthony R; Selter, Liselotte L; Matsumoto, Takashi; Keller, Beat

    2011-02-01

    The Triticum aestivum (bread wheat) disease resistance gene Lr34 confers durable, race non-specific protection against three fungal pathogens, and has been a highly relevant gene for wheat breeding since the green revolution. Lr34, located on chromosome 7D, encodes an ATP-binding cassette (ABC) transporter. Both wheat cultivars with and without Lr34-based resistance encode a putatively functional protein that differ by only two amino acid polymorphisms. In this study, we focused on the identification and characterization of homoeologous and orthologous Lr34 genes in hexaploid wheat and other grasses. In hexaploid wheat we found an expressed and putatively functional Lr34 homoeolog located on chromosome 4A, designated Lr34-B. Another homoeologous Lr34 copy, located on chromosome 7A, was disrupted by the insertion of repetitive elements. Protein sequences of LR34-B and LR34 were 97% identical. Orthologous Lr34 genes were detected in the genomes of Oryza sativa (rice) and Sorghum bicolor (sorghum). Zea mays (maize), Brachypodium distachyon and Hordeum vulgare (barley) lacked Lr34 orthologs, indicating independent deletion of this particular ABC transporter. Lr34 was part of a gene-rich island on the wheat D genome. We found gene colinearity on the homoeologous A and B genomes of hexaploid wheat, but little microcolinearity in other grasses. The homoeologous LR34-B protein and the orthologs from rice and sorghum have the susceptible haplotype for the two critical polymorphisms distinguishing the LR34 proteins from susceptible and resistant wheat cultivars. We conclude that the particular Lr34-haplotype found in resistant wheat cultivars is unique. It probably resulted from functional gene diversification that occurred after the polyploidization event that was at the origin of cultivated bread wheat. PMID:21265893

  14. NAD-dependent aromatic alcohol dehydrogenase in wheats (Triticum L.) and goatgrasses (Aegilops L.): evolutionary genetics.

    PubMed

    Jaaska, V

    1984-04-01

    Evolutionary electrophoretic variation of a NAD-specific aromatic alcohol dehydrogenase, AADH-E, in wheat and goatgrass species is described and discussed in comparison with a NAD-specific alcohol dehydrogenase (ADH-A) and a NADP-dependent AADH-B studied previously. Cultivated tetraploid emmer wheats (T. turgidum s. l.) and hexaploid bread wheats (T. aestivum s. l.) are all fixed for a heterozygous triplet, E(0.58)/E(0.64). The slowest isoenzyme, E(0.58), is controlled by a homoeoallelic gene on the chromosome arm 6AL of T. aestivum cv. 'Chinese Spring' and is inherent in all diploid wheats, T. monococcum s. Str., T. boeoticum s. l. and T. urartu. The fastest isoenzyme, E(0.64), is presumably controlled by the B- and D-genome homoeoalleles of the bread wheat and is the commonest alloenzyme of diploid goat-grasses, including Ae. speltaides and Ae. tauschii. The tetraploid T. timopheevii s. str. has a particular heterozygous triplet E(0.56)/E(0.71), whereas the hexaploid T. zhukovskyi exhibited polymorphism with electromorphs characteristic of T. timopheevii and T. monococcum. Wild tetraploid wheats, T. dicoccoides and T. araraticum, showed partially homologous intraspecific variation of AADH-E with heterozygous triplets E(0.58)/E(0.64) (the commonest), E(0.58)/E(0.71), E(0.45)/E(0.58), E(0.48)/E(0.58) and E(0.56)/E(0.58) recorded. Polyploid goatgrasses of the D-genome group, excepting Ae. cylindrica, are fixed for the common triplet E(0.58)/E(0.64). Ae. cylindrica and polyploid goatgrasses of the C(u)-genome group, excepting Ae. kotschyi, are homozygous for E(0.64). Ae. kotschyi is exceptional, showing fixed heterozygosity for both AADH-E and ADH-A with unique triplets E(0.56)/E(0.64) and A(0.49)/A(0.56). PMID:24258843

  15. Identification and characterization of more than 4 million intervarietal SNPs across the group 7 chromosomes of bread wheat.

    PubMed

    Lai, Kaitao; Lorenc, Michał T; Lee, Hong Ching; Berkman, Paul J; Bayer, Philipp Emanuel; Visendi, Paul; Ruperao, Pradeep; Fitzgerald, Timothy L; Zander, Manuel; Chan, Chon-Kit Kenneth; Manoli, Sahana; Stiller, Jiri; Batley, Jacqueline; Edwards, David

    2015-01-01

    Despite being a major international crop, our understanding of the wheat genome is relatively poor due to its large size and complexity. To gain a greater understanding of wheat genome diversity, we have identified single nucleotide polymorphisms between 16 Australian bread wheat varieties. Whole-genome shotgun Illumina paired read sequence data were mapped to the draft assemblies of chromosomes 7A, 7B and 7D to identify more than 4 million intervarietal SNPs. SNP density varied between the three genomes, with much greater density observed on the A and B genomes than the D genome. This variation may be a result of substantial gene flow from the tetraploid Triticum turgidum, which possesses A and B genomes, during early co-cultivation of tetraploid and hexaploid wheat. In addition, we examined SNP density variation along the chromosome syntenic builds and identified genes in low-density regions which may have been selected during domestication and breeding. This study highlights the impact of evolution and breeding on the bread wheat genome and provides a substantial resource for trait association and crop improvement. All SNP data are publically available on a generic genome browser GBrowse at www.wheatgenome.info. PMID:25147022

  16. Uniquely identifying wheat plant structures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Uniquely naming wheat (Triticum aestivum L. em Thell) plant parts is useful for communicating plant development research and the effects of environmental stresses on normal wheat development. Over the past 30+ years, several naming systems have been proposed for wheat shoot, leaf, spike, spikelet, ...

  17. High-density SNP genotyping array for hexaploid wheat and its secondary and tertiary gene pool.

    PubMed

    Winfield, Mark O; Allen, Alexandra M; Burridge, Amanda J; Barker, Gary L A; Benbow, Harriet R; Wilkinson, Paul A; Coghill, Jane; Waterfall, Christy; Davassi, Alessandro; Scopes, Geoff; Pirani, Ali; Webster, Teresa; Brew, Fiona; Bloor, Claire; King, Julie; West, Claire; Griffiths, Simon; King, Ian; Bentley, Alison R; Edwards, Keith J

    2016-05-01

    In wheat, a lack of genetic diversity between breeding lines has been recognized as a significant block to future yield increases. Species belonging to bread wheat's secondary and tertiary gene pools harbour a much greater level of genetic variability, and are an important source of genes to broaden its genetic base. Introgression of novel genes from progenitors and related species has been widely employed to improve the agronomic characteristics of hexaploid wheat, but this approach has been hampered by a lack of markers that can be used to track introduced chromosome segments. Here, we describe the identification of a large number of single nucleotide polymorphisms that can be used to genotype hexaploid wheat and to identify and track introgressions from a variety of sources. We have validated these markers using an ultra-high-density Axiom(®) genotyping array to characterize a range of diploid, tetraploid and hexaploid wheat accessions and wheat relatives. To facilitate the use of these, both the markers and the associated sequence and genotype information have been made available through an interactive web site. PMID:26466852

  18. AB-QTL analysis in winter wheat: II. Genetic analysis of seedling and field resistance against leaf rust in a wheat advanced backcross population

    PubMed Central

    Naz, Ali Ahmad; Kunert, Antje; Lind, Volker; Léon, Jens

    2008-01-01

    The present study aimed to localize exotic quantitative trait locus (QTL) alleles for the improvement of leaf rust (P.triticina) resistance in an advanced backcross (AB) population, B22, which is derived from a cross between the winter wheat cultivar Batis (Triticumaestivum) and the synthetic wheat accession Syn022L. The latter was developed from hybridization of T.turgidum ssp. dicoccoides and T.tauschii. Altogether, 250 BC2F3 lines of B22 were assessed for seedling resistance against the leaf rust isolate 77WxR under controlled conditions. In addition, field resistance against leaf rust was evaluated by assessing symptom severity under natural infestation across multiple environments. Simultaneously, population B22 was genotyped with a total of 97 SSR markers, distributed over the wheat A, B and D genomes. The phenotype and genotype data were subjected to QTL analysis by applying a 3-factorial mixed model analysis of variance including the marker genotype as a fixed effect and the environments, the lines and the marker by environment interactions as random effects. The QTL analysis revealed six putative QTLs for seedling resistance and seven for field resistance. For seedling resistance, the effects of exotic QTL alleles improved resistance at all detected loci. The maximum decrease of disease symptoms (−46.3%) was associated with marker locus Xbarc149 on chromosome 1D. For field resistance, two loci had stable main effects across environments and five loci exhibited marker by environment interaction effects. The strongest effects were detected at marker locus Xbarc149 on chromosome 1D, at which the exotic allele decreased seedling symptoms by 46.3% and field symptoms by 43.6%, respectively. Some of the detected QTLs co-localized with known resistance genes, while others appear to be as novel resistance loci. Our findings indicate, that the exotic wheat accession Syn022L may be useful for the improvement of leaf rust resistance in cultivated wheat. PMID

  19. Reckoning wheat yield trends

    NASA Astrophysics Data System (ADS)

    Lin, M.; Huybers, P.

    2012-06-01

    Wheat yields have increased approximately linearly since the mid-twentieth century across the globe, but stagnation of these trends has now been suggested for several nations. We present a new statistical test for whether a yield time series has leveled off and apply it to wheat yield data from 47 different regions to show that nearly half of the production within our sample has transitioned to level trajectories. With the major exception of India, the majority of leveling in wheat yields occurs within developed nations—including the United Kingdom, France and Germany—whose policies appear to have disincentivized yield increases relative to other objectives. The effects of climate change and of yields nearing their maximum potential may also be important.

  20. A diploid wheat TILLING resource for wheat functional genomics

    PubMed Central

    2012-01-01

    Background Triticum monococcum L., an A genome diploid einkorn wheat, was the first domesticated crop. As a diploid, it is attractive genetic model for the study of gene structure and function of wheat-specific traits. Diploid wheat is currently not amenable to reverse genetics approaches such as insertion mutagenesis and post-transcriptional gene silencing strategies. However, TILLING offers a powerful functional genetics approach for wheat gene analysis. Results We developed a TILLING population of 1,532 M2 families using EMS as a mutagen. A total of 67 mutants were obtained for the four genes studied. Waxy gene mutation frequencies are known to be 1/17.6 - 34.4 kb DNA in polyploid wheat TILLING populations. The T. monococcum diploid wheat TILLING population had a mutation frequency of 1/90 kb for the same gene. Lignin biosynthesis pathway genes- COMT1, HCT2, and 4CL1 had mutation frequencies of 1/86 kb, 1/92 kb and 1/100 kb, respectively. The overall mutation frequency of the diploid wheat TILLING population was 1/92 kb. Conclusion The mutation frequency of a diploid wheat TILLING population was found to be higher than that reported for other diploid grasses. The rate, however, is lower than tetraploid and hexaploid wheat TILLING populations because of the higher tolerance of polyploids to mutations. Unlike polyploid wheat, most mutants in diploid wheat have a phenotype amenable to forward and reverse genetic analysis and establish diploid wheat as an attractive model to study gene function in wheat. We estimate that a TILLING population of 5, 520 will be needed to get a non-sense mutation for every wheat gene of interest with 95% probability. PMID:23134614

  1. Endothelial progenitor cells: identity defined?

    PubMed Central

    Timmermans, Frank; Plum, Jean; Yöder, Mervin C; Ingram, David A; Vandekerckhove, Bart; Case, Jamie

    2009-01-01

    Abstract In the past decade, researchers have gained important insights on the role of bone marrow (BM)-derived cells in adult neovascularization. A subset of BM-derived cells, called endothelial progenitor cells (EPCs), has been of particular interest, as these cells were suggested to home to sites of neovascularization and neoendothelialization and differentiate into endothelial cells (ECs) in situ, a process referred to as postnatal vasculogenesis. Therefore, EPCs were proposed as a potential regenerative tool for treating human vascular disease and a possible target to restrict vessel growth in tumour pathology. However, conflicting results have been reported in the field, and the identification, characterization, and exact role of EPCs in vascular biology is still a subject of much discussion. The focus of this review is on the controversial issues in the field of EPCs which are related to the lack of a unique EPC marker, identification challenges related to the paucity of EPCs in the circulation, and the important phenotypical and functional overlap between EPCs, haematopoietic cells and mature ECs. We also discuss our recent findings on the origin of endothelial outgrowth cells (EOCs), showing that this in vitro defined EC population does not originate from circulating CD133+ cells or CD45+ haematopoietic cells. PMID:19067770

  2. Divergent Development of Hexaploid Triticale by a Wheat – Rye –Psathyrostachys huashanica Trigeneric Hybrid Method

    PubMed Central

    Huang, Juan; Wang, Yujie; Li, Daiyan; Diao, Chengdou; Zhu, Wei; Tang, Yao; Wang, Yi; Fan, Xing; Zeng, Jian; Xu, Lili; Sha, Lina; Zhang, Haiqin; Zhou, Yonghong

    2016-01-01

    Hexaploid triticale is an important forage crop and a promising energy plant. Some forms were previously reported for developing the hexaploid triticale, such as crossing tetraploid wheat or hexaploid wheat with rye, crossing hexaploid triticale and/or hexaploid wheat with octoploid triticale, and spontaneously appearing in the selfed progenies of octoploid triticale. In the present study, we developed an effective method for production of diverse types of hexaploid triticale via wheat—rye—Psathyrostachys huashanica trigeneric hybrid. Genomic in situ hybridization (GISH) and fluorescence in situ hybridization (FISH) karyotyping revealed that D genome chromosomes were completely eliminated and the whole A, B, and R genome chromosomes were retained in three lines. More interestingly, the composite genome of the line K14-489-2 consisted of complete A and B genomes and chromosomes 1D, 2R, 3R, 4R, 5R, 6R, and 7R, that of line K14-491-2 was 12 A-genome (1A-6A), 14 B-genome (1B-7B), 12 R-genome (1R-3R, 5R-7R), and chromosomes 1D and 3D, and that of the line K14-547-1 had 26A/B and 14R chromosomes, plus one pair of centric 6BL/2DS translocations. This finding implies that some of D genome chromosomes can be spontaneously and stably incorporated into the hexaploid triticale. Additionally, a variety of high-molecular-weight glutenin subunits (HMW-GS) compositions were detected in the six hexaploid triticale lines, respectively. Besides, compared with its recurrent triticale parent Zhongsi828, these lines showed high level of resistance to stripe rust (Puccinia striiformis f. sp. tritici, Pst) pathogens prevalent in China, including V26/Gui 22. These new hexaploid triticales not only enhanced diversification of triticale but also could be utilized as valuable germplasm for wheat improvement. PMID:27182983

  3. 21 CFR 184.1322 - Wheat gluten.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Wheat gluten. 184.1322 Section 184.1322 Food and... Substances Affirmed as GRAS § 184.1322 Wheat gluten. (a) Wheat gluten (CAS Reg. No. 8002-80-0) is the principal protein component of wheat and consists mainly of gliadin and glutenin. Wheat gluten is...

  4. 21 CFR 184.1322 - Wheat gluten.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Wheat gluten. 184.1322 Section 184.1322 Food and... Substances Affirmed as GRAS § 184.1322 Wheat gluten. (a) Wheat gluten (CAS Reg. No. 8002-80-0) is the principal protein component of wheat and consists mainly of gliadin and glutenin. Wheat gluten is...

  5. 21 CFR 184.1322 - Wheat gluten.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Wheat gluten. 184.1322 Section 184.1322 Food and... Substances Affirmed as GRAS § 184.1322 Wheat gluten. (a) Wheat gluten (CAS Reg. No. 8002-80-0) is the principal protein component of wheat and consists mainly of gliadin and glutenin. Wheat gluten is...

  6. 21 CFR 184.1322 - Wheat gluten.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Wheat gluten. 184.1322 Section 184.1322 Food and... Substances Affirmed as GRAS § 184.1322 Wheat gluten. (a) Wheat gluten (CAS Reg. No. 8002-80-0) is the principal protein component of wheat and consists mainly of gliadin and glutenin. Wheat gluten is...

  7. Modelling Wheat Production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In wheat, a shorter pre-anthesis phase is often associated with increased grain protein content (GPC) but decreased grain yield. Cultivar differences in pre-anthesis development are mainly determined by vernalization requirement, photoperiod sensitivity and earliness per se. This research examines w...

  8. Registration of Colter wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Colter’ (Reg. No. CV-1099, PI 670156) hard red winter wheat (Triticum aestivum L.) was developed and released by the Montana Agricultural Experiment Stations in September 2013. Colter was derived from the cross MT9982*2/BZ9W96-895. MT9982 is a sib selection of 'Yellowstone', and BZ9W96-895 is an unr...

  9. Registration of 'Otto' Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Resistance to strawbreaker foot rot (caused by Oculimacula yallundae Crous & W. Gams and O. acuformis Crous & W. Gams) and to stripe rust (caused by Puccinia striiformis Westend. f. sp. tritici Eriks.) are important traits for winter wheat cultivars produced in the Pacifi Northwest region of the Uni...

  10. Registration of 'Guymon' wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'Guymon' (Reg. No. CV-_______, PI 643133) is a hard white (HW) winter wheat (Triticum aestivum L.) cultivar developed and released cooperatively by the Oklahoma Agric. Exp. Stn. (AES) and the USDA-ARS in 2005. It is recommended for grain-only and dual-purpose production systems in an area of the so...

  11. Registration of Warhorse wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'Warhorse' (Reg. No. CV-1096, PI 670157) hard red winter (HRW) wheat (Triticum aestivum L.) was developed and released by the Montana Agricultural Experiment Station in September 2013. Warhorse is of unknown pedigree, derived from a composite of three topcrosses made to the same F1 population in 200...

  12. Registration of Camelot Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'Camelot ' (PI 653832) hard red winter wheat (Triticum aestivum L.) was developed cooperatively by the Nebraska Agricultural Experiment Station and the USDA-ARS and released in 2008. In addition to researchers at the releasing institutions, USDA-ARS researchers at Manhattan, KS, and St. Paul, MN, ...

  13. Registration of 'Chesapeake' Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Chesapeake’ (Reg. No. CV-1011, PI 643935) is a soft red winter wheat (Triticum aestivum L.) that was jointly developed and released by the Maryland Agricultural Experiment Station, Department of Plant Science and Landscape Architecture, and the Virginia Agricultural Experiment Station in 2005. Ches...

  14. Registration of "Merl" Wheat.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Merl’ (Reg. No. CV- , PI 658598) soft red winter (SRW) wheat (Triticum aestivum L.)developed and tested as VA03W-412 by the Virginia Agricultural Experiment Station was released in March 2009. Merl was derived from the three-way cross ‘Roane’ / Pioneer Brand ‘2643’ // ‘38158’ (PI 619052). Merl is a...

  15. Registration of 'Tiger' wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Tiger’ hard white winter wheat (Triticum aestivum L.) was developed at Research Center-Hays, Kansas State University and released by Kansas Agricultural Experiment Station in 2010. Tiger was selected from a three-way cross KS98H245/’Trego’//KS98HW518 made in 1999 at Hays, KS. The objective of this ...

  16. Registration of 'Cowboy' wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'Cowboy' (Reg. No. CV-1095, PI 668564) hard red winter wheat (Triticum aestivum L.) was developed by the Colorado Agricultural Experiment Station and released cooperatively by Colorado State University (CSU) and the University of Wyoming (UWYO) in August 2011. In addition to researchers at CSU and U...

  17. Hypersensitive Response-Like Reaction Is Associated with Hybrid Necrosis in Interspecific Crosses between Tetraploid Wheat and Aegilops tauschii Coss

    PubMed Central

    Mizuno, Nobuyuki; Hosogi, Naoki; Park, Pyoyun; Takumi, Shigeo

    2010-01-01

    interspecific hybrids. Only Ae. tauschii accessions without such inhibiting factors could be candidates for the D-genome donor for the present hexaploid wheat. PMID:20593003

  18. Neural Progenitors Adopt Specific Identities by Directly Repressing All Alternative Progenitor Transcriptional Programs

    PubMed Central

    Kutejova, Eva; Sasai, Noriaki; Shah, Ankita; Gouti, Mina; Briscoe, James

    2016-01-01

    Summary In the vertebrate neural tube, a morphogen-induced transcriptional network produces multiple molecularly distinct progenitor domains, each generating different neuronal subtypes. Using an in vitro differentiation system, we defined gene expression signatures of distinct progenitor populations and identified direct gene-regulatory inputs corresponding to locations of specific transcription factor binding. Combined with targeted perturbations of the network, this revealed a mechanism in which a progenitor identity is installed by active repression of the entire transcriptional programs of other neural progenitor fates. In the ventral neural tube, sonic hedgehog (Shh) signaling, together with broadly expressed transcriptional activators, concurrently activates the gene expression programs of several domains. The specific outcome is selected by repressive input provided by Shh-induced transcription factors that act as the key nodes in the network, enabling progenitors to adopt a single definitive identity from several initially permitted options. Together, the data suggest design principles relevant to many developing tissues. PMID:26972603

  19. Neural Progenitors Adopt Specific Identities by Directly Repressing All Alternative Progenitor Transcriptional Programs.

    PubMed

    Kutejova, Eva; Sasai, Noriaki; Shah, Ankita; Gouti, Mina; Briscoe, James

    2016-03-21

    In the vertebrate neural tube, a morphogen-induced transcriptional network produces multiple molecularly distinct progenitor domains, each generating different neuronal subtypes. Using an in vitro differentiation system, we defined gene expression signatures of distinct progenitor populations and identified direct gene-regulatory inputs corresponding to locations of specific transcription factor binding. Combined with targeted perturbations of the network, this revealed a mechanism in which a progenitor identity is installed by active repression of the entire transcriptional programs of other neural progenitor fates. In the ventral neural tube, sonic hedgehog (Shh) signaling, together with broadly expressed transcriptional activators, concurrently activates the gene expression programs of several domains. The specific outcome is selected by repressive input provided by Shh-induced transcription factors that act as the key nodes in the network, enabling progenitors to adopt a single definitive identity from several initially permitted options. Together, the data suggest design principles relevant to many developing tissues. PMID:26972603

  20. Wheat allergy: diagnosis and management.

    PubMed

    Cianferoni, Antonella

    2016-01-01

    Triticum aestivum (bread wheat) is the most widely grown crop worldwide. In genetically predisposed individuals, wheat can cause specific immune responses. A food allergy to wheat is characterized by T helper type 2 activation which can result in immunoglobulin E (IgE) and non-IgE mediated reactions. IgE mediated reactions are immediate, are characterized by the presence of wheat-specific IgE antibodies, and can be life-threatening. Non-IgE mediated reactions are characterized by chronic eosinophilic and lymphocytic infiltration of the gastrointestinal tract. IgE mediated responses to wheat can be related to wheat ingestion (food allergy) or wheat inhalation (respiratory allergy). A food allergy to wheat is more common in children and can be associated with a severe reaction such as anaphylaxis and wheat-dependent, exercise-induced anaphylaxis. An inhalation induced IgE mediated wheat allergy can cause baker's asthma or rhinitis, which are common occupational diseases in workers who have significant repetitive exposure to wheat flour, such as bakers. Non-IgE mediated food allergy reactions to wheat are mainly eosinophilic esophagitis (EoE) or eosinophilic gastritis (EG), which are both characterized by chronic eosinophilic inflammation. EG is a systemic disease, and is associated with severe inflammation that requires oral steroids to resolve. EoE is a less severe disease, which can lead to complications in feeding intolerance and fibrosis. In both EoE and EG, wheat allergy diagnosis is based on both an elimination diet preceded by a tissue biopsy obtained by esophagogastroduodenoscopy in order to show the effectiveness of the diet. Diagnosis of IgE mediated wheat allergy is based on the medical history, the detection of specific IgE to wheat, and oral food challenges. Currently, the main treatment of a wheat allergy is based on avoidance of wheat altogether. However, in the near future immunotherapy may represent a valid way to treat IgE mediated reactions to

  1. Wheat allergy: diagnosis and management

    PubMed Central

    Cianferoni, Antonella

    2016-01-01

    Triticum aestivum (bread wheat) is the most widely grown crop worldwide. In genetically predisposed individuals, wheat can cause specific immune responses. A food allergy to wheat is characterized by T helper type 2 activation which can result in immunoglobulin E (IgE) and non-IgE mediated reactions. IgE mediated reactions are immediate, are characterized by the presence of wheat-specific IgE antibodies, and can be life-threatening. Non-IgE mediated reactions are characterized by chronic eosinophilic and lymphocytic infiltration of the gastrointestinal tract. IgE mediated responses to wheat can be related to wheat ingestion (food allergy) or wheat inhalation (respiratory allergy). A food allergy to wheat is more common in children and can be associated with a severe reaction such as anaphylaxis and wheat-dependent, exercise-induced anaphylaxis. An inhalation induced IgE mediated wheat allergy can cause baker’s asthma or rhinitis, which are common occupational diseases in workers who have significant repetitive exposure to wheat flour, such as bakers. Non-IgE mediated food allergy reactions to wheat are mainly eosinophilic esophagitis (EoE) or eosinophilic gastritis (EG), which are both characterized by chronic eosinophilic inflammation. EG is a systemic disease, and is associated with severe inflammation that requires oral steroids to resolve. EoE is a less severe disease, which can lead to complications in feeding intolerance and fibrosis. In both EoE and EG, wheat allergy diagnosis is based on both an elimination diet preceded by a tissue biopsy obtained by esophagogastroduodenoscopy in order to show the effectiveness of the diet. Diagnosis of IgE mediated wheat allergy is based on the medical history, the detection of specific IgE to wheat, and oral food challenges. Currently, the main treatment of a wheat allergy is based on avoidance of wheat altogether. However, in the near future immunotherapy may represent a valid way to treat IgE mediated reactions to

  2. STELLAR BINARY COMPANIONS TO SUPERNOVA PROGENITORS

    SciTech Connect

    Kochanek, Christopher S.

    2009-12-20

    For typical models of binary statistics, 50%-80% of core-collapse supernova (ccSN) progenitors are members of a stellar binary at the time of the explosion. Independent of any consequences of mass transfer, this has observational consequences that can be used to study the binary properties of massive stars. In particular, the secondary companion to the progenitor of a Type Ib/c SN is frequently (approx50%) the more optically luminous star since the high effective temperatures of the stripped progenitors make it relatively easy for a lower luminosity, cooler secondary to emit more optical light. Secondaries to the lower mass progenitors of Type II SN will frequently produce excess blue emission relative to the spectral energy distribution of the red primary. Available data constrain the models weakly. Any detected secondaries also provide an independent lower bound on the progenitor mass and, for historical SN, show that it was not a Type Ia event. Bright ccSN secondaries have an unambiguous, post-explosion observational signature-strong, blueshifted, relatively broad absorption lines created by the developing SN remnant (SNR). These can be used to locate historical SN with bright secondaries, confirm that a source is a secondary, and, potentially, measure abundances of ccSN ejecta. Luminous, hot secondaries will re-ionize the SNR on timescales of 100-1000 yr that are faster than re-ionization by the reverse shock, creating peculiar H II regions due to the high metallicity and velocities of the ejecta.

  3. Characterization and expression analysis of WOX5 genes from wheat and its relatives.

    PubMed

    Zhao, Shan; Jiang, Qian-Tao; Ma, Jian; Zhang, Xiao-Wei; Zhao, Quan-Zhi; Wang, Xiu-Ying; Wang, Chang-Shui; Cao, Xue; Lu, Zhen-Xiang; Zheng, You-Liang; Wei, Yu-Ming

    2014-03-01

    The WUSCHEL (WUS)-related homeobox (WOX) gene family plays an important role in coordinating gene transcription in the early phases of embryogenesis. In this study, we isolated and characterized WOX5 from common wheat and its relatives Triticum monococcum, Triticum urartu, Aegilops speltoides, Aegilops searsii, Aegilops sharonensis, Aegilops longissima, Aegilops bicornis, Aegilops tauschii, and Triticum turgidum. The size of the characterized WOX5 alleles ranged from 1029 to 1038 bp and encompassed the complete open reading frame (ORF) as well as 5' upstream and 3' downstream sequences. Domain prediction analysis showed that the putative primary structures of wheat WOX5 protein include the highly conserved homeodomain besides the WUS-box domain and the EAR-like domain, which is/are present in some members of the WOX protein family. The full-length ORF was subcloned into a prokaryotic expression vector pET30a, and an approximate 26-kDa protein was successfully expressed in Escherichia coli BL21 (DE3) cells with IPTG induction. The WOX5 genes from wheat-related species exhibit a similar structure to and high sequence similarity with WOX5 genes from common wheat. The degree of divergence and phylogenetic tree analysis among WOX5 alleles suggested the existence of three homoeologous copies in the A, B, or D genome of common wheat. Quantitative PCR results showed that TaWOX5 was primarily expressed in the root and calli induced by auxin and cytokinin, indicating that TaWOX5 may play a role related to root formation or development and is associated with hormone regulation in somatic embryogenesis. PMID:24368329

  4. Molecular Mapping of Wheat: Major Genes and Rearrangements in Homoeologous Groups 4, 5, and 7

    PubMed Central

    Nelson, J. C.; Sorrells, M. E.; Van-Deynze, A. E.; Lu, Y. H.; Atkinson, M.; Bernard, M.; Leroy, P.; Faris, J. D.; Anderson, J. A.

    1995-01-01

    A molecular-marker linkage map of hexaploid wheat (Triticum aestivum L. em. Thell) provides a framework for integration with the classical genetic map and a record of the chromosomal rearrangements involved in the evolution of this crop species. We have constructed restriction fragment length polymorphism (RFLP) maps of the A-, B-, and D-genome chromosomes of homoeologous groups 4, 5, and 7 of wheat using 114 F(7) lines from a synthetic X cultivated wheat cross and clones from 10 DNA libraries. Chromosomal breakpoints for known ancestral reciprocal translocations involving these chromosomes and for a known pericentric inversion on chromosome 4A were localized by linkage and aneuploid analysis. Known genes mapped include the major vernalization genes Vrn1 and Vrn3 on chromosome arms 5AL and 5DL, the red-coleoptile gene Rc1 on 7AS, and presumptively the leaf-rust (Puccinia recondita f.sp. tritici) resistance gene Lr34 on 7DS and the kernel-hardness gene Ha on 5DS. RFLP markers previously obtained for powdery-mildew (Blumeria graminis f.sp. tritici) resistance genes Pm2 and Pm1 were localized on chromosome arms 5DS and 7AL. PMID:8647405

  5. History and current status of wheat miRNAs using next-generation sequencing and their roles in development and stress.

    PubMed

    Budak, Hikmet; Khan, Zaeema; Kantar, Melda

    2015-05-01

    As small molecules that aid in posttranscriptional silencing, microRNA (miRNA) discovery and characterization have vastly benefited from the recent development and widespread application of next-generation sequencing (NGS) technologies. Several miRNAs were identified through sequencing of constructed small RNA libraries, whereas others were predicted by in silico methods using the recently accumulating sequence data. NGS was a major breakthrough in efforts to sequence and dissect the genomes of plants, including bread wheat and its progenitors, which have large, repetitive and complex genomes. Availability of survey sequences of wheat whole genome and its individual chromosomes enabled researchers to predict and assess wheat miRNAs both in the subgenomic and whole genome levels. Moreover, small RNA construction and sequencing-based studies identified several putative development- and stress-related wheat miRNAs, revealing their differential expression patterns in specific developmental stages and/or in response to stress conditions. With the vast amount of wheat miRNAs identified in recent years, we are approaching to an overall knowledge on the wheat miRNA repertoire. In the following years, more comprehensive research in relation to miRNA conservation or divergence across wheat and its close relatives or progenitors should be performed. Results may serve valuable in understanding both the significant roles of species-specific miRNAs and also provide us information in relation to the dynamics between miRNAs and evolution in wheat. Furthermore, putative development- or stress-related miRNAs identified should be subjected to further functional analysis, which may be valuable in efforts to develop wheat with better resistance and/or yield. PMID:24962995

  6. Exploring the Progenitors of Fast Radio Bursts

    NASA Astrophysics Data System (ADS)

    Burke-Spolaor, Sarah; Kramer, Michael; Bhat, Ramesh; Kulkarni, S. R.; Keller, Stefan; Champion, David; Flynn, Chris; Kasliwal, Mansi

    2014-10-01

    Fast Radio Bursts (FRBs) are millisecond bursts that are broadly evidenced to arise from extragalactic, but yet unknown, progenitors. They have presented a true mystery in that so far no progenitor theory can adequately account for their observed properties. We request observations that will glean basic information on FRB progenitors. Our observations will execute a specific test of whether FRBs originate in nearby galaxies. We have also designed our target field and time request to enable a thorough exploration of optical counterparts before, during, and after any detected FRB episode. Additionally, with a number depending on the typical distance to FRBs, our observations will raise the running list of total FRB discoveries by 10-60%.

  7. Progenitor cells in the adult pancreas.

    PubMed

    Holland, Andrew M; Góñez, L Jorge; Harrison, Leonard C

    2004-01-01

    The beta-cell mass in the adult pancreas possesses the ability to undergo limited regeneration following injury. Identifying the progenitor cells involved in this process and understanding the mechanisms leading to their maturation will open new avenues for the treatment of type 1 diabetes. However, despite steady advances in determining the molecular basis of early pancreatic development, the identification of pancreatic stem cells or beta-cell progenitors and the molecular mechanisms underlying beta-cell regeneration remain unclear. Recent advances in the directed differentiation of embryonic and adult stem cells has heightened interest in the possible application of stem cell therapy in the treatment of type 1 diabetes. Drawing on the expanding knowledge of pancreas development, beta-cell regeneration and stem cell research, this review focuses on progenitor cells in the adult pancreas as a potential source of beta-cells. PMID:14737742

  8. Derivation of high-purity oligodendroglial progenitors.

    PubMed

    Hatch, Maya N; Nistor, Gabriel; Keirstead, Hans S

    2009-01-01

    Oligodendrocytes are a type of glial cells that play a critical role in supporting the central nervous system (CNS), in particular insulating axons within the CNS by wrapping them with a myelin sheath, thereby enabling saltatory conduction. They are lost, and myelin damaged - demyelination - in a wide variety of neurological disorders. Replacing depleted cell types within demyelinated areas, however, has been shown experimentally to achieve remyelination and so help restore function. One method to produce oligodendrocytes for cellular replacement therapies is through the use of progenitor or stem cells. The ability to differentiate progenitor or stem cells into high-purity fates not only permits the generation of specific cells for transplantation therapies, but also provides powerful tools for studying cellular mechanisms of development. This chapter outlines methods of generating high-purity OPCs from multipotent neonatal progenitor or human embryonic stem cells. PMID:19378196

  9. TaER Expression Is Associated with Transpiration Efficiency Traits and Yield in Bread Wheat

    PubMed Central

    Zheng, Jiacheng; Yang, Zhiyuan; Madgwick, Pippa J.; Carmo-Silva, Elizabete; Parry, Martin A. J.; Hu, Yin-Gang

    2015-01-01

    ERECTA encodes a receptor-like kinase and is proposed as a candidate for determining transpiration efficiency of plants. Two genes homologous to ERECTA in Arabidopsis were identified on chromosomes 6 (TaER2) and 7 (TaER1) of bread wheat (Triticum aestivum L.), with copies of each gene on the A, B and D genomes of wheat. Similar expression patterns were observed for TaER1 and TaER2 with relatively higher expression of TaER1 in flag leaves of wheat at heading (Z55) and grain-filling (Z73) stages. Significant variations were found in the expression levels of both TaER1 and TaER2 in the flag leaves at both growth stages among 48 diverse bread wheat varieties. Based on the expression of TaER1 and TaER2, the 48 wheat varieties could be classified into three groups having high (5 varieties), medium (27 varieties) and low (16 varieties) levels of TaER expression. Significant differences were also observed between the three groups varying for TaER expression for several transpiration efficiency (TE)- related traits, including stomatal density (SD), transpiration rate, photosynthetic rate (A), instant water use efficiency (WUEi) and carbon isotope discrimination (CID), and yield traits of biomass production plant-1 (BYPP) and grain yield plant-1 (GYPP). Correlation analysis revealed that the expression of TaER1 and TaER2 at the two growth stages was significantly and negatively associated with SD (P<0.01), transpiration rate (P<0.05) and CID (P<0.01), while significantly and positively correlated with flag leaf area (FLA, P<0.01), A (P<0.05), WUEi (P<0.05), BYPP (P<0.01) and GYPP (P<0.01), with stronger correlations for TaER1 than TaER2 and at grain-filling stage than at heading stage. These combined results suggested that TaER involved in development of transpiration efficiency -related traits and yield in bread wheat, implying a function for TaER in regulating leaf development of bread wheat and contributing to expression of these traits. Moreover, the results indicate

  10. Wheat yield forecasts using LANDSAT data

    NASA Technical Reports Server (NTRS)

    Colwell, J. E.; Rice, D. P.; Nalepka, R. F.

    1977-01-01

    Several considerations of winter wheat yield prediction using LANDSAT data were discussed. In addition, a simple technique which permits direct early season forecasts of wheat production was described.

  11. Pigment Cell Progenitors in Zebrafish Remain Multipotent through Metamorphosis.

    PubMed

    Singh, Ajeet Pratap; Dinwiddie, April; Mahalwar, Prateek; Schach, Ursula; Linker, Claudia; Irion, Uwe; Nüsslein-Volhard, Christiane

    2016-08-01

    The neural crest is a transient, multipotent embryonic cell population in vertebrates giving rise to diverse cell types in adults via intermediate progenitors. The in vivo cell-fate potential and lineage segregation of these postembryonic progenitors is poorly understood, and it is unknown if and when the progenitors become fate restricted. We investigate the fate restriction in the neural crest-derived stem cells and intermediate progenitors in zebrafish, which give rise to three distinct adult pigment cell types: melanophores, iridophores, and xanthophores. By inducing clones in sox10-expressing cells, we trace and quantitatively compare the pigment cell progenitors at four stages, from embryogenesis to metamorphosis. At all stages, a large fraction of the progenitors are multipotent. These multipotent progenitors have a high proliferation ability, which diminishes with fate restriction. We suggest that multipotency of the nerve-associated progenitors lasting into metamorphosis may have facilitated the evolution of adult-specific traits in vertebrates. PMID:27453500

  12. Molecular organization and comparative analysis of chromosome 5B of the wild wheat ancestor Triticum dicoccoides

    PubMed Central

    Ani Akpinar, Bala; Yuce, Meral; Lucas, Stuart; Vrána, Jan; Burešová, Veronika; Doležel, Jaroslav; Budak, Hikmet

    2015-01-01

    Wild emmer wheat, Triticum turgidum ssp. dicoccoides is the wild relative of Triticum turgidum, the progenitor of durum and bread wheat, and maintains a rich allelic diversity among its wild populations. The lack of adequate genetic and genomic resources, however, restricts its exploitation in wheat improvement. Here, we report next-generation sequencing of the flow-sorted chromosome 5B of T. dicoccoides to shed light into its genome structure, function and organization by exploring the repetitive elements, protein-encoding genes and putative microRNA and tRNA coding sequences. Comparative analyses with its counterparts in modern and wild wheats suggest clues into the B-genome evolution. Syntenic relationships of chromosome 5B with the model grasses can facilitate further efforts for fine-mapping of traits of interest. Mapping of 5B sequences onto the root transcriptomes of two additional T. dicoccoides genotypes, with contrasting drought tolerances, revealed several thousands of single nucleotide polymorphisms, of which 584 shared polymorphisms on 228 transcripts were specific to the drought-tolerant genotype. To our knowledge, this study presents the largest genomics resource currently available for T. dicoccoides, which, we believe, will encourage the exploitation of its genetic and genomic potential for wheat improvement to meet the increasing demand to feed the world. PMID:26084265

  13. BAC libraries of Triticum urartu, Aegilops speltoides and Ae. tauschii, the diploid ancestors of polyploid wheat.

    PubMed

    Akhunov, E D; Akhunova, A R; Dvorák, J

    2005-11-01

    Triticum urartu, Aegilops speltoides and Ae. tauschii are respectively the immediate diploid sources, or their closest relatives, of the A, B and D genomes of polyploid wheats. Here we report the construction and characterization of arrayed large-insert libraries in a bacterial artificial chromosome (BAC) vector, one for each of these diploid species. The libraries are equivalent to 3.7, 5.4 and 4.1 of the T. urartu, Ae. speltoides, Ae. tauschii genomes, respectively. The predicted levels of genome coverage were confirmed by library hybridization with single-copy genes. The libraries were used to estimate the proportion of known repeated nucleotide sequences and gene content in each genome by BAC-end sequencing. Repeated sequence families previously detected in Triticeae accounted for 57, 61 and 57% of the T. urartu, Ae. speltoides and Ae. tauschii genomes, and coding regions accounted for 5.8, 4.5 and 4.8%, respectively. PMID:16177898

  14. [Non-celiac disease non-wheat allergy wheat sensitivity].

    PubMed

    Zopf, Yurdagül; Dieterich, Walburga

    2015-11-01

    Non-celiac non-wheat allergy wheat sensitivity is regarded as discrete glutensensitivity diagnosed after the exclusion of celiac disease and wheat allergy. Due to the absence of reliable biomarkers no exact prevalence rates are known and estimations range between 0,5-6 %. Soon after ingestion of wheat, patients complain of intestinal symptoms mainly bloating, abdominal pain, diarrhea or nausea which improve fast under glutenfree diet. Often extraintestinal manifestation as tiredness, muscle or joint pain, headache and depression are reported. Actually, there are no serological markers and no intestinal mucosal damage was found in patients. The underlying mechanism of the disease is completely unknown and beside of gluten other wheat proteins as well as amylase-trypsin-inhibitor or short chain sugars are discussed as triggers. In addition, the involvement of the intestinal microbiome in pathology of glutensensitivity must be considered. PMID:26536646

  15. Analyses of alpha/beta-type gliadin genes from diploid and hexaploid wheats.

    PubMed

    Reeves, C D; Okita, T W

    1987-01-01

    The alpha/beta-gliadin genes isolated from both hexaploid wheat (cv. Yamhill) and the diploid A genome progenitor Triticum urartu had remarkably similar sequences and differ by only a few point mutations. Primer extension analysis indicated that the transcriptional start points for individual genes in the family cluster within a few nucleotides. Comparison of the promoter region of several alpha/beta-gliadin and B-hordein genes reveals two conserved regions at about -130 and -250 bp. DNA from the hexaploid cultivars, Cheyenne and Chinese Spring, and the diploid progenitors T. urartu and Aegilops squarrosa was analysed by Southern blotting. Restriction fragment lengths of the alpha/beta-gliadin genes varied only slightly between the various wheats, although the overall copy number varied significantly. A region between approx. -1700 and -700 bp upstream from the TATA box was highly repeated in all three wheat genomes. For the hexaploid-derived gene, over 1700 bp of sequence upstream from the TATA box was determined, revealing an additional open reading frame between approx. -1550 and -1250 bp relative to the gliadin TATA box. Northern blot analysis indicated that RNA homologous to this repeated sequence family was present only in developing seed and accumulated to a maximum at late stages of maturation. PMID:3038689

  16. Human Liver Progenitor Cells for Liver Repair

    PubMed Central

    Lombard, Catherine A.; Prigent, Julie; Sokal, Etienne M.

    2013-01-01

    Because of their high proliferative capacity, resistance to cryopreservation, and ability to differentiate into hepatocyte-like cells, stem and progenitor cells have recently emerged as attractive cell sources for liver cell therapy, a technique used as an alternative to orthotopic liver transplantation in the treatment of various hepatic ailments ranging from metabolic disorders to end-stage liver disease. Although stem and progenitor cells have been isolated from various tissues, obtaining them from the liver could be an advantage for the treatment of hepatic disorders. However, the techniques available to isolate these stem/progenitor cells are numerous and give rise to cell populations with different morphological and functional characteristics. In addition, there is currently no established consensus on the tests that need to be performed to ensure the quality and safety of these cells when used clinically. The purpose of this review is to describe the different types of liver stem/progenitor cells currently reported in the literature, discuss their suitability and limitations in terms of clinical applications, and examine how the culture and transplantation techniques can potentially be improved to achieve a better clinical outcome. PMID:26858860

  17. In vivo identification of periodontal progenitor cells.

    PubMed

    Roguljic, H; Matthews, B G; Yang, W; Cvija, H; Mina, M; Kalajzic, I

    2013-08-01

    The periodontal ligament contains progenitor cells; however, their identity and differentiation potential in vivo remain poorly characterized. Previous results have suggested that periodontal tissue progenitors reside in perivascular areas. Therefore, we utilized a lineage-tracing approach to identify and track periodontal progenitor cells from the perivascular region in vivo. We used an alpha-smooth muscle actin (αSMA) promoter-driven and tamoxifen-inducible Cre system (αSMACreERT2) that, in combination with a reporter mouse line (Ai9), permanently labels a cell population, termed 'SMA9'. To trace the differentiation of SMA9-labeled cells into osteoblasts/cementoblasts, we utilized a Col2.3GFP transgene, while expression of Scleraxis-GFP was used to follow differentiation into periodontal ligament fibroblasts during normal tissue formation and remodeling following injury. In uninjured three-week-old SMA9 mice, tamoxifen labeled a small population of cells in the periodontal ligament that expanded over time, particularly in the apical region of the root. By 17 days and 7 weeks after labeling, some SMA9-labeled cells expressed markers indicating differentiation into mature lineages, including cementocytes. Following injury, SMA9 cells expanded, and differentiated into cementoblasts, osteoblasts, and periodontal ligament fibroblasts. SMA9-labeled cells represent a source of progenitors that can give rise to mature osteoblasts, cementoblasts, and fibroblasts within the periodontium. PMID:23735585

  18. The progenitors of subluminous type Ia supernovae

    SciTech Connect

    Howell, D. Andrew

    2001-02-01

    We find that spectroscopically peculiar subluminous SNe Ia come from an old population. Of the thirteen subluminous SNe Ia known, nine are found in E/S0 galaxies, and the remainder are found in early-type spirals. The probability that this is a chance occurrence is only 0.1%. The finding that subluminous SNe Ia are associated with an older stellar population indicates that for a sufficiently large lookback time (already accessible in current high redshift searches) they will not be found. Due to a scarcity in old populations, hydrogen and helium main sequence stars and He red giant stars that undergo Roche lobe overflow are unlikely to be the progenitors of subluminous SNe Ia. Earlier findings that overluminous SNe Ia (DELTA m{sub 15} (B) < 0.94) come from a young progenitor population are confirmed. The fact that subluminous SNe Ia and overluminous SNe Ia come from different progenitor populations and also have different properties is a prediction of the CO white dwarf merger progenitor scenario.

  19. The homoeologous genes encoding chalcone-flavanone isomerase in Triticum aestivum L.: structural characterization and expression in different parts of wheat plant.

    PubMed

    Shoeva, Olesya Y; Khlestkina, Elena K; Berges, Helene; Salina, Elena A

    2014-04-01

    Chalcone-flavanone isomerase (CHI; EC 5.5.1.6.) participates in the early step of flavonoid biosynthesis, related to plant adaptive and protective responses to environmental stress. The bread wheat genomic sequences encoding CHI were isolated, sequenced and mapped to the terminal segment of the long arms of chromosomes 5A, 5B and 5D. The loss of the final Chi intron and junction of the two last exons was found in the wheat A, B and D genomes compared to the Chi sequences of most other plant species. Each of the three diploid genomes of hexaploid wheat encodes functional CHI; however, transcription of the three homoeologous genes is not always co-regulated. In particular, the three genes demonstrated different response to salinity in roots: Chi-D1 was up-regulated, Chi-A1 responds medially, whereas Chi-B1 was not activated at all. The observed variation in transcriptional activity between the Chi homoeologs is in a good agreement with structural diversification of their promoter sequences. In addition, the correlation between Chi transcription and anthocyanin pigmentation in different parts of wheat plant has been studied. The regulatory genes controlling anthocyanin pigmentation of culm and pericarp modulated transcription of the Chi genes. However, in other organs, there was no strong relation between tissue pigmentation and the transcription of the Chi genes, suggesting complex regulation of the Chi expression in most parts of wheat plant. PMID:24480448

  20. SUPERNOVA REMNANT PROGENITOR MASSES IN M31

    SciTech Connect

    Jennings, Zachary G.; Williams, Benjamin F.; Dalcanton, Julianne J.; Gilbert, Karoline M.; Fouesneau, Morgan; Weisz, Daniel R.; Murphy, Jeremiah W.; Dolphin, Andrew E. E-mail: adolphin@raytheon.com

    2012-12-10

    Using Hubble Space Telescope photometry, we age-date 59 supernova remnants (SNRs) in the spiral galaxy M31 and use these ages to estimate zero-age main-sequence masses (M{sub ZAMS}) for their progenitors. To accomplish this, we create color-magnitude diagrams (CMDs) and employ CMD fitting to measure the recent star formation history of the regions surrounding cataloged SNR sites. We identify any young coeval population that likely produced the progenitor star, then assign an age and uncertainty to that population. Application of stellar evolution models allows us to infer the M{sub ZAMS} from this age. Because our technique is not contingent on identification or precise location of the progenitor star, it can be applied to the location of any known SNRs. We identify significant young star formation around 53 of the 59 SNRs and assign progenitor masses to these, representing a factor of {approx}2 increase over currently measured progenitor masses. We consider the remaining six SNRs as either probable Type Ia candidates or the result of core-collapse progenitors that have escaped their birth sites. In general, the distribution of recovered progenitor masses is bottom-heavy, showing a paucity of the most massive stars. If we assume a single power-law distribution, dN/dM{proportional_to}M{sup {alpha}}, then we find a distribution that is steeper than a Salpeter initial mass function (IMF) ({alpha} = -2.35). In particular, we find values of {alpha} outside the range -2.7 {>=} {alpha} {>=} -4.4 to be inconsistent with our measured distribution at 95% confidence. If instead we assume a distribution that follows a Salpeter IMF up to some maximum mass, then we find that values of M{sub Max} > 26 are inconsistent with the measured distribution at 95% confidence. In either scenario, the data suggest that some fraction of massive stars may not explode. The result is preliminary and requires more SNRs and further analysis. In addition, we use our distribution to estimate a

  1. Wheat landraces: A mini review

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Farmers developed and utilized diverse wheat landraces to meet the complexity of a multitude of spatio-temporal, agro-ecological systems and to provide reliable sustenance and a sustainable food source to local communities. The genetic structure of wheat landraces is an evolutionary approach to surv...

  2. Registration of 'LCS Wizard' wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this research was to develop widely adapted hard winter wheat (Triticum aestivum L.) varieties to meet the needs of mills, bakeries, and consumers in the eastern and Great Plains regions of the United States. ‘LCS Wizard’ (Reg. No. CV-1111, PI 669574), a hard red winter (HRW) wheat,...

  3. Development of the Wheat Plant

    Technology Transfer Automated Retrieval System (TEKTRAN)

    1) Wheat development is important in creating structures such as leaves and roots needed to capture resources, and also to create the structures ultimately needed to produce viable seed or the desired quality for grain. 2) Wheat canopy development can be considered at many scales of the plant but of...

  4. Registration of 'Rollag' spring wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium head blight (FHB) (caused primarily by Fusarium graminearum Schwabe) is a disease that annually threatens wheat (Triticum aestivum L.) grown in the northern plains of the United States. Resistance to this disease is a high priority trait in the University of Minnesota’s spring wheat breedi...

  5. Registration of 'Thunder CL' Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'Thunder CL' (Reg. No. CV- , PI XXXXXX) hard white winter wheat (Triticum aestivum L.) was developed by the Colorado Agricultural Experiment Station and released in August 2008 through a marketing agreement with the Colorado Wheat Research Foundation. In addition to researchers at Colorado State Uni...

  6. Registration of 'Bill Brown' wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'Bill Brown’ (Reg. No. CV-133, PI 653260) hard red winter wheat (Triticum aestivum L.) was developed by the Colorado Agricultural Experiment Station and released in August 2007 through an exclusive marketing agreement with the Colorado Wheat Research Foundation. In addition to researchers at Colorad...

  7. Registration of Vision 40 Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The potential exists to develop and market hard winter wheat (Triticum aestivum L.) in the eastern United States, where a majority of the mills, bakeries, and consumers reside. The primary objective of this study was to develop adapted and competitive hard winter wheat cultivars possessing high-valu...

  8. Registration of 'Bill Brown' Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Bill Brown’ (Reg. No. CV-133, PI 653260) hard red winter wheat (Triticum aestivum L.) was developed by the Colorado Agricultural Experiment Station and released in August 2007 through an exclusive marketing agreement with the Colorado Wheat Research Foundation. In addition to researchers at Colorad...

  9. Using genic sequence capture in combination with a syntenic pseudo genome to map a deletion mutant in a wheat species.

    PubMed

    Gardiner, Laura-Jayne; Gawroński, Piotr; Olohan, Lisa; Schnurbusch, Thorsten; Hall, Neil; Hall, Anthony

    2014-12-01

    Mapping-by-sequencing analyses have largely required a complete reference sequence and employed whole genome re-sequencing. In species such as wheat, no finished genome reference sequence is available. Additionally, because of its large genome size (17 Gb), re-sequencing at sufficient depth of coverage is not practical. Here, we extend the utility of mapping by sequencing, developing a bespoke pipeline and algorithm to map an early-flowering locus in einkorn wheat (Triticum monococcum L.) that is closely related to the bread wheat genome A progenitor. We have developed a genomic enrichment approach using the gene-rich regions of hexaploid bread wheat to design a 110-Mbp NimbleGen SeqCap EZ in solution capture probe set, representing the majority of genes in wheat. Here, we use the capture probe set to enrich and sequence an F2 mapping population of the mutant. The mutant locus was identified in T. monococcum, which lacks a complete genome reference sequence, by mapping the enriched data set onto pseudo-chromosomes derived from the capture probe target sequence, with a long-range order of genes based on synteny of wheat with Brachypodium distachyon. Using this approach we are able to map the region and identify a set of deleted genes within the interval. PMID:25205592

  10. Hard Spring Wheat Technical Committee 2006 Crop

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Breeders’ experimental lines of wheat are evaluated for overall quality before being released for commercial production. The Hard Spring Wheat Technical Committee provides milling and baking quality data on breeders’ experimental lines of wheat that are annually submitted to the Wheat Quality Counc...

  11. Incidence of Wheat streak mosaic virus, Triticum mosaic virus, and Wheat mosaic virus in wheat curl mites recovered from maturing winter wheat spikes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat curl mites (WCM; Aceria tosichella) transmit Wheat streak mosaic virus (WSMV), Triticum mosaic virus (TriMV), and Wheat mosaic virus (WMoV) to wheat (Triticum aestivum L.) in the Great Plains region of the United States. These viruses can be detected in single, double, or triple combinations i...

  12. Simultaneous transfer, introgression, and genomic localization of genes for resistance to stem rust race TTKSK (Ug99) from Aegilops tauschii to wheat.

    PubMed

    Olson, Eric L; Rouse, Matthew N; Pumphrey, Michael O; Bowden, Robert L; Gill, Bikram S; Poland, Jesse A

    2013-05-01

    Wheat production is currently threatened by widely virulent races of the wheat stem rust fungus, Puccinia graminis f. sp. tritici, that are part of the TTKSK (also known as 'Ug99') race group. The diploid D genome donor species Aegilops tauschii (2n = 2x = 14, DD) is a readily accessible source of resistance to TTKSK and its derivatives that can be transferred to hexaploid wheat, Triticum aestivum (2n = 6x = 42, AABBDD). To expedite transfer of TTKSK resistance from Ae. tauschii, a direct hybridization approach was undertaken that integrates gene transfer, mapping, and introgression into one process. Direct crossing of Ae. tauschii accessions with an elite wheat breeding line combines the steps of gene transfer and introgression while development of mapping populations during gene transfer enables the identification of closely linked markers. Direct crosses were made using TTKSK-resistant Ae. tauschii accessions TA1662 and PI 603225 as males and a stem rust-susceptible T. aestivum breeding line, KS05HW14, as a female. Embryo rescue enabled recovery of F1 (ABDD) plants that were backcrossed as females to the hexaploid recurrent parent. Stem rust-resistant BC1F1 plants from each Ae. tauschii donor source were used as males to generate BC2F1 mapping populations. Bulked segregant analysis of BC2F1 genotypes was performed using 70 SSR loci distributed across the D genome. Using this approach, stem rust resistance genes from both accessions were located on chromosome arm 1DS and mapped using SSR and EST-STS markers. An allelism test indicated the stem rust resistance gene transferred from PI 603225 is Sr33. Race specificity suggests the stem rust resistance gene transferred from TA1662 is unique and this gene has been temporarily designated SrTA1662. Stem rust resistance genes derived from TA1662 and PI 603225 have been made available with selectable molecular markers in genetic backgrounds suitable for stem rust resistance breeding. PMID:23377571

  13. Drought Tolerance in Wheat

    PubMed Central

    Prodhan, Zakaria Hossain; Faruq, Golam

    2013-01-01

    Drought is one of the most important phenomena which limit crops' production and yield. Crops demonstrate various morphological, physiological, biochemical, and molecular responses to tackle drought stress. Plants' vegetative and reproductive stages are intensively influenced by drought stress. Drought tolerance is a complicated trait which is controlled by polygenes and their expressions are influenced by various environmental elements. This means that breeding for this trait is so difficult and new molecular methods such as molecular markers, quantitative trait loci (QTL) mapping strategies, and expression patterns of genes should be applied to produce drought tolerant genotypes. In wheat, there are several genes which are responsible for drought stress tolerance and produce different types of enzymes and proteins for instance, late embryogenesis abundant (lea), responsive to abscisic acid (Rab), rubisco, helicase, proline, glutathione-S-transferase (GST), and carbohydrates during drought stress. This review paper has concentrated on the study of water limitation and its effects on morphological, physiological, biochemical, and molecular responses of wheat with the possible losses caused by drought stress. PMID:24319376

  14. Drought tolerance in wheat.

    PubMed

    Nezhadahmadi, Arash; Prodhan, Zakaria Hossain; Faruq, Golam

    2013-01-01

    Drought is one of the most important phenomena which limit crops' production and yield. Crops demonstrate various morphological, physiological, biochemical, and molecular responses to tackle drought stress. Plants' vegetative and reproductive stages are intensively influenced by drought stress. Drought tolerance is a complicated trait which is controlled by polygenes and their expressions are influenced by various environmental elements. This means that breeding for this trait is so difficult and new molecular methods such as molecular markers, quantitative trait loci (QTL) mapping strategies, and expression patterns of genes should be applied to produce drought tolerant genotypes. In wheat, there are several genes which are responsible for drought stress tolerance and produce different types of enzymes and proteins for instance, late embryogenesis abundant (lea), responsive to abscisic acid (Rab), rubisco, helicase, proline, glutathione-S-transferase (GST), and carbohydrates during drought stress. This review paper has concentrated on the study of water limitation and its effects on morphological, physiological, biochemical, and molecular responses of wheat with the possible losses caused by drought stress. PMID:24319376

  15. Progenitor cells for ocular surface regenerative therapy.

    PubMed

    Casaroli-Marano, Ricardo P; Nieto-Nicolau, Nuria; Martínez-Conesa, Eva M

    2013-01-01

    The integrity and normal function of the corneal epithelium are essential for maintaining the cornea's transparency and vision. The existence of a cell population with progenitor characteristics in the limbus maintains a dynamic of constant epithelial repair and renewal. Currently, cell-based therapies for bio-replacement, such as cultured limbal epithelial transplantation and cultured oral mucosal epithelial transplantation, present very encouraging clinical results for treating limbal stem cell deficiencies. Another emerging therapeutic strategy consists of obtaining and implementing human progenitor cells of different origins using tissue engineering methods. The development of cell-based therapies using stem cells, such as human adult mesenchymal stromal cells, represents a significant breakthrough in the treatment of certain eye diseases and also offers a more rational, less invasive and more physiological approach to ocular surface regeneration. PMID:23257987

  16. Noninvasive Imaging of Administered Progenitor Cells

    SciTech Connect

    Steven R Bergmann, M.D., Ph.D.

    2012-12-03

    The objective of this research grant was to develop an approach for labeling progenitor cells, specifically those that we had identified as being able to replace ischemic heart cells, so that the distribution could be followed non-invasively. In addition, the research was aimed at determining whether administration of progenitor cells resulted in improved myocardial perfusion and function. The efficiency and toxicity of radiolabeling of progenitor cells was to be evaluated. For the proposed clinical protocol, subjects with end-stage ischemic coronary artery disease were to undergo a screening cardiac positron emission tomography (PET) scan using N-13 ammonia to delineate myocardial perfusion and function. If they qualified based on their PET scan, they would undergo an in-hospital protocol whereby CD34+ cells were stimulated by the administration of granulocytes-colony stimulating factor (G-CSF). CD34+ cells would then be isolated by apharesis, and labeled with indium-111 oxine. Cells were to be re-infused and subjects were to undergo single photon emission computed tomography (SPECT) scanning to evaluate uptake and distribution of labeled progenitor cells. Three months after administration of progenitor cells, a cardiac PET scan was to be repeated to evaluate changes in myocardial perfusion and/or function. Indium oxine is a radiopharmaceutical for labeling of autologous lymphocytes. Indium-111 (In-111) decays by electron capture with a t{sub ½} of 67.2 hours (2.8 days). Indium forms a saturated complex that is neutral, lipid soluble, and permeates the cell membrane. Within the cell, the indium-oxyquinolone complex labels via indium intracellular chelation. Following leukocyte labeling, ~77% of the In-111 is incorporated in the cell pellet. The presence of red cells and /or plasma reduces the labeling efficacy. Therefore, the product needed to be washed to eliminate plasma proteins. This repeated washing can damage cells. The CD34 selected product was a 90

  17. Cardiac progenitor cells for heart repair

    PubMed Central

    Le, TYL; Chong, JJH

    2016-01-01

    Stem cell therapy is being investigated as an innovative and promising strategy to restore cardiac function in patients with heart failure. Several stem cell populations, including adult (multipotent) stem cells from developed organs and tissues, have been tested for cardiac repair with encouraging clinical and pre-clinical results. The heart has been traditionally considered a post-mitotic organ, however, this view has recently changed with the identification of stem/progenitor cells residing within the adult heart. Given their cardiac developmental origins, these endogenous cardiac progenitor cells (CPCs) may represent better candidates for cardiac cell therapy compared with stem cells from other organs such as the bone marrow and adipose tissue. This brief review will outline current research into CPC populations and their cardiac repair/regenerative potential. PMID:27551540

  18. POPULATION SYNTHESIS AND GAMMA RAY BURST PROGENITORS

    SciTech Connect

    C. L. FREYER

    2000-12-11

    Population synthesis studies of binaries are always limited by a myriad of uncertainties from the poorly understood effects of binary mass transfer and common envelope evolution to the many uncertainties that still remain in stellar evolution. But the importance of these uncertainties depends both upon the objects being studied and the questions asked about these objects. Here I review the most critical uncertainties in the population synthesis of gamma-ray burst progenitors. With a better understanding of these uncertainties, binary population synthesis can become a powerful tool in understanding, and constraining, gamma-ray burst models. In turn, as gamma-ray bursts become more important as cosmological probes, binary population synthesis of gamma-ray burst progenitors becomes an important tool in cosmology.

  19. Interneuron Progenitor Transplantation to Treat CNS Dysfunction

    PubMed Central

    Chohan, Muhammad O.; Moore, Holly

    2016-01-01

    Due to the inadequacy of endogenous repair mechanisms diseases of the nervous system remain a major challenge to scientists and clinicians. Stem cell based therapy is an exciting and viable strategy that has been shown to ameliorate or even reverse symptoms of CNS dysfunction in preclinical animal models. Of particular importance has been the use of GABAergic interneuron progenitors as a therapeutic strategy. Born in the neurogenic niches of the ventral telencephalon, interneuron progenitors retain their unique capacity to disperse, integrate and induce plasticity in adult host circuitries following transplantation. Here we discuss the potential of interneuron based transplantation strategies as it relates to CNS disease therapeutics. We also discuss mechanisms underlying their therapeutic efficacy and some of the challenges that face the field. PMID:27582692

  20. Human progenitor cells for bone engineering applications.

    PubMed

    de Peppo, G M; Thomsen, P; Karlsson, C; Strehl, R; Lindahl, A; Hyllner, J

    2013-06-01

    In this report, the authors review the human skeleton and the increasing burden of bone deficiencies, the limitations encountered with the current treatments and the opportunities provided by the emerging field of cell-based bone engineering. Special emphasis is placed on different sources of human progenitor cells, as well as their pros and cons in relation to their utilization for the large-scale construction of functional bone-engineered substitutes for clinical applications. It is concluded that, human pluripotent stem cells represent a valuable source for the derivation of progenitor cells, which combine the advantages of both embryonic and adult stem cells, and indeed display high potential for the construction of functional substitutes for bone replacement therapies. PMID:23642054

  1. Genome wide identification of C1-2i zinc finger proteins and their response to abiotic stress in hexaploid wheat.

    PubMed

    Cheuk, Arnaud; Houde, Mario

    2016-04-01

    The C1-2i wheat Q-type C2H2 zinc finger protein (ZFP) transcription factor subclass has been reported to play important roles in plant stress responses. This subclass of ZFPs has not been studied in hexaploid wheat (Triticum aestivum) and we aimed to identify all members of this subclass and evaluate their responses to different abiotic stresses causing oxidative stress. Exploiting the recently published wheat draft genome sequence, we identified 53 members (including homoeologs from A, B and D genomes) of the C1-2i wheat Q-type C2H2 ZFPs (TaZFPs) representing 21 genes. Evolution analysis revealed that 9 TaZFPs members are directly inherited from the parents Triticum urartu and Aegilops tauschii, while 15 diverged through neoploidization events. This TaZFP subclass is responsive to the oxidative stress generator H2O2 and to high light, drought stress and flooding. Most TaZFPs are responsive to H2O2 (37/53), high light (44/53), flooding (31/53) or drought (37/53); 32 TaZFPs were up-regulated by at least 3 stresses and 16 were responsive to all stresses tested. A large number of these TaZFPs were physically mapped on different wheat draft genome sequences with known markers useful for QTL mapping. Our results show that the C1-2i subclass of TaZFPs is associated with responses to different abiotic stresses and that most TaZFPs (30/53 or 57 %) are located on group 5 chromosomes known to be involved in environment adaptation. Detailed characterization of these novel wheat TaZFPs and their association to QTL or eQTL may help to design wheat cultivars with improved tolerance to abiotic stress. PMID:26638714

  2. The GLOBE 3D Genome Platform - towards a novel system-biological paper tool to integrate the huge complexity of genome organization and function.

    PubMed

    Knoch, Tobias A; Lesnussa, Michael; Kepper, Nick; Eussen, Hubert B; Grosveld, Frank G

    2009-01-01

    Genomes are tremendous co-evolutionary holistic systems for molecular storage, processing and fabrication of information. Their system-biological complexity remains, however, still largely mysterious, despite immense sequencing achievements and huge advances in the understanding of the general sequential, three-dimensional and regulatory organization. Here, we present the GLOBE 3D Genome Platform a completely novel grid based virtual "paper" tool and in fact the first system-biological genome browser integrating the holistic complexity of genomes in a single easy comprehensible platform: Based on a detailed study of biophysical and IT requirements, every architectural level from sequence to morphology of one or several genomes can be approached in a real and in a symbolic representation simultaneously and navigated by continuous scale-free zooming within a unique three-dimensional OpenGL and grid driven environment. In principle an unlimited number of multi-dimensional data sets can be visualized, customized in terms of arrangement, shape, colour, and texture etc. as well as accessed and annotated individually or in groups using internal or external data bases/facilities. Any information can be searched and correlated by importing or calculating simple relations in real-time using grid resources. A general correlation and application platform for more complex correlative analysis and a front-end for system-biological simulations both using again the huge capabilities of grid infrastructures is currently under development. Hence, the GLOBE 3D Genome Platform is an example of a grid based approach towards a virtual desktop for genomic work combining the three fundamental distributed resources: i) visual data representation, ii) data access and management, and iii) data analysis and creation. Thus, the GLOBE 3D Genome Platform is the novel system-biology oriented information system urgently needed to access, present, annotate, and to simulate the holistic genome

  3. Chondrogenic Progenitor Cells Respond to Cartilage Injury

    PubMed Central

    Choe, Hyeonghun; Zheng, Hongjun; Yu, Yin; Jang, Keewoong; Walter, Morgan W.; Lehman, Abigail D.; Ding, Lei; Buckwalter, Joseph A.; Martin, James A.

    2014-01-01

    Objective Hypocellularity resulting from chondrocyte death in the aftermath of mechanical injury is thought to contribute to posttraumatic osteoarthritis. However, we observed that nonviable areas in cartilage injured by blunt impact were repopulated within 7–14 days by cells that appeared to migrate from the surrounding matrix. The aim of this study was to assess our hypothesis that the migrating cell population included chondrogenic progenitor cells that were drawn to injured cartilage by alarmins. Methods Osteochondral explants obtained from mature cattle were injured by blunt impact or scratching, resulting in localized chondrocyte death. Injured sites were serially imaged by confocal microscopy, and migrating cells were evaluated for chondrogenic progenitor characteristics. Chemotaxis assays were used to measure the responses to chemokines, injury-conditioned medium, dead cell debris, and high mobility group box chromosomal protein 1 (HMGB-1). Results Migrating cells were highly clonogenic and multipotent and expressed markers associated with chondrogenic progenitor cells. Compared with chondrocytes, these cells overexpressed genes involved in proliferation and migration and underexpressed cartilage matrix genes. They were more active than chondrocytes in chemotaxis assays and responded to cell lysates, conditioned medium, and HMGB-1. Glycyrrhizin, a chelator of HMGB-1 and a blocking antibody to receptor for advanced glycation end products (RAGE), inhibited responses to cell debris and conditioned medium and reduced the numbers of migrating cells on injured explants. Conclusion Injuries that caused chondrocyte death stimulated the emergence and homing of chondrogenic progenitor cells, in part via HMGB-1 release and RAGE-mediated chemotaxis. Their repopulation of the matrix could promote the repair of chondral damage that might otherwise contribute to progressive cartilage loss. PMID:22777600

  4. Multipotent Hematopoietic Progenitors Divide Asymmetrically to Create Progenitors of the Lymphomyeloid and Erythromyeloid Lineages

    PubMed Central

    Görgens, André; Ludwig, Anna-Kristin; Möllmann, Michael; Krawczyk, Adalbert; Dürig, Jan; Hanenberg, Helmut; Horn, Peter A.; Giebel, Bernd

    2014-01-01

    Summary Hematopoietic stem and progenitor cells (HSPCs) can self-renew and create committed progenitors, a process supposed to involve asymmetric cell divisions (ACDs). Previously, we had linked the kinetics of CD133 expression with ACDs but failed to detect asymmetric segregation of classical CD133 epitopes on fixed, mitotic HSPCs. Now, by using a novel anti-CD133 antibody (HC7), we confirmed the occurrence of asymmetric CD133 segregation on paraformaldehyde-fixed and living HSPCs. After showing that HC7 binding does not recognizably affect biological features of human HSPCs, we studied ACDs in different HSPC subtypes and determined the developmental potential of arising daughter cells at the single-cell level. Approximately 70% of the HSPCs of the multipotent progenitor (MPP) fraction studied performed ACDs, and about 25% generated lymphoid-primed multipotent progenitor (LMPP) as wells as erythromyeloid progenitor (EMP) daughter cells. Since MPPs hardly created daughter cells maintaining MPP characteristics, our data suggest that under conventional culture conditions, ACDs are lineage instructive rather than self-renewing. PMID:25448068

  5. Evolution and Adaptation of Wild Emmer Wheat Populations to Biotic and Abiotic Stresses.

    PubMed

    Huang, Lin; Raats, Dina; Sela, Hanan; Klymiuk, Valentina; Lidzbarsky, Gabriel; Feng, Lihua; Krugman, Tamar; Fahima, Tzion

    2016-08-01

    The genetic bottlenecks associated with plant domestication and subsequent selection in man-made agroecosystems have limited the genetic diversity of modern crops and increased their vulnerability to environmental stresses. Wild emmer wheat, the tetraploid progenitor of domesticated wheat, distributed along a wide range of ecogeographical conditions in the Fertile Crescent, has valuable "left behind" adaptive diversity to multiple diseases and environmental stresses. The biotic and abiotic stress responses are conferred by series of genes and quantitative trait loci (QTLs) that control complex resistance pathways. The study of genetic diversity, genomic organization, expression profiles, protein structure and function of biotic and abiotic stress-resistance genes, and QTLs could shed light on the evolutionary history and adaptation mechanisms of wild emmer populations for their natural habitats. The continuous evolution and adaptation of wild emmer to the changing environment provide novel solutions that can contribute to safeguarding food for the rapidly growing human population. PMID:27296141

  6. Whole-genome profiling and shotgun sequencing delivers an anchored, gene-decorated, physical map assembly of bread wheat chromosome 6A.

    PubMed

    Poursarebani, Naser; Nussbaumer, Thomas; Simková, Hana; Safář, Jan; Witsenboer, Hanneke; van Oeveren, Jan; Doležel, Jaroslav; Mayer, Klaus F X; Stein, Nils; Schnurbusch, Thorsten

    2014-07-01

    Bread wheat (Triticum aestivum L.) is the most important staple food crop for 35% of the world's population. International efforts are underway to facilitate an increase in wheat production, of which the International Wheat Genome Sequencing Consortium (IWGSC) plays an important role. As part of this effort, we have developed a sequence-based physical map of wheat chromosome 6A using whole-genome profiling (WGP™). The bacterial artificial chromosome (BAC) contig assembly tools fingerprinted contig (fpc) and linear topological contig (ltc) were used and their contig assemblies were compared. A detailed investigation of the contigs structure revealed that ltc created a highly robust assembly compared with those formed by fpc. The ltc assemblies contained 1217 contigs for the short arm and 1113 contigs for the long arm, with an L50 of 1 Mb. To facilitate in silico anchoring, WGP™ tags underlying BAC contigs were extended by wheat and wheat progenitor genome sequence information. Sequence data were used for in silico anchoring against genetic markers with known sequences, of which almost 79% of the physical map could be anchored. Moreover, the assigned sequence information led to the 'decoration' of the respective physical map with 3359 anchored genes. Thus, this robust and genetically anchored physical map will serve as a framework for the sequencing of wheat chromosome 6A, and is of immediate use for map-based isolation of agronomically important genes/quantitative trait loci located on this chromosome. PMID:24813060

  7. Differential response of wild and cultivated wheats to water deficits during grain development: changes in soluble carbohydrates and invertases.

    PubMed

    Suneja, Yadhu; Gupta, Anil K; Sharma, Achla; Bains, Navtej S

    2015-04-01

    Wheat, staple food crop of the world, is sensitive to drought, especially during the grain-filling period. Water soluble carbohydrates (WSCs), stem reserve mobilization and higher invertase activity in the developing grains are important biochemical traits for breeding wheat to enhance tolerance to terminal drought. These traits were studied for three accessions of Triticum dicoccoides(a tetraploid wheat progenitor species) - acc 7054 (EC 171812), acc 7079 (EC 171837) and acc 14004 (G-194-3 M-6 M) selected previously on the basis of grain filling characteristics. Check wheat cultivars- PBW-343 (a popular bread wheat cultivar for irrigated environments) and C-306 (widely adapted variety for rain-fed agriculture) were also included in this set. Analysis of variance revealed significant genotypic differences for the content of water soluble carbohydrates, activity of acid invertase and alkaline invertase. Acc 7079 was found to be a very efficient mobilizer of water soluble carbohydrates (236.43 mg g(-1) peduncle DW) when averaged over irrigated and rain-fed conditions. Acid invertase activity revealed marked genotypic differences between wild and cultivated wheats. Alkaline invertase activity was highest in Acc 7079 when pooled across both the environments. On the whole, acc 7079 qualifies as a suitable donor for enhancing tolerance of bread wheat to terminal drought. The association of physio-biochemical differences observed with grain filling attributes on one hand and molecular markers on the other could be of use in improving wheat for water stress conditions. PMID:25964711

  8. TOX3 regulates neural progenitor identity.

    PubMed

    Sahu, Sanjeeb Kumar; Fritz, Alina; Tiwari, Neha; Kovacs, Zsuzsa; Pouya, Alireza; Wüllner, Verena; Bora, Pablo; Schacht, Teresa; Baumgart, Jan; Peron, Sophie; Berninger, Benedikt; Tiwari, Vijay K; Methner, Axel

    2016-07-01

    The human genomic locus for the transcription factor TOX3 has been implicated in susceptibility to restless legs syndrome and breast cancer in genome-wide association studies, but the physiological role of TOX3 remains largely unknown. We found Tox3 to be predominantly expressed in the developing mouse brain with a peak at embryonic day E14 where it co-localizes with the neural stem and progenitor markers Nestin and Sox2 in radial glia of the ventricular zone and intermediate progenitors of the subventricular zone. Tox3 is also expressed in neural progenitor cells obtained from the ganglionic eminence of E15 mice that express Nestin, and it specifically binds the Nestin promoter in chromatin immunoprecipitation assays. In line with this, over-expression of Tox3 increased Nestin promoter activity, which was cooperatively enhanced by treatment with the stem cell self-renewal promoting Notch ligand Jagged and repressed by pharmacological inhibition of Notch signaling. Knockdown of Tox3 in the subventricular zone of E12.5 mouse embryos by in utero electroporation of Tox3 shRNA revealed a reduced Nestin expression and decreased proliferation at E14 and a reduced migration to the cortical plate in E16 embryos in electroporated cells. Together, these results argue for a role of Tox3 in the development of the nervous system. PMID:27080130

  9. Endothelial progenitor cells in hematologic malignancies

    PubMed Central

    Saulle, Ernestina; Castelli, Germana; Pelosi, Elvira

    2016-01-01

    Studies carried out in the last years have improved the understanding of the cellular and molecular mechanisms controlling angiogenesis during adult life in normal and pathological conditions. Some of these studies have led to the identification of some progenitor cells that sustain angiogenesis through indirect, paracrine mechanisms (hematopoietic angiogenic cells) and through direct mechanisms, i.e., through their capacity to generate a progeny of phenotypically and functionally competent endothelial cells [endothelial colony forming cells (ECFCs)]. The contribution of these progenitors to angiogenetic processes under physiological and pathological conditions is intensively investigated. Angiogenetic mechanisms are stimulated in various hematological malignancies, including chronic myeloid leukemia (CML), acute myeloid leukemia (AML), myelodysplastic syndromes and multiple myeloma, resulting in an increased angiogenesis that contributes to disease progression. In some of these conditions there is preliminary evidence that some endothelial cells could derive from the malignant clone, thus leading to the speculation that the leukemic cell derives from the malignant transformation of a hemangioblastic progenitor, i.e., of a cell capable of differentiation to the hematopoietic and to the endothelial cell lineages. Our understanding of the mechanisms underlying increased angiogenesis in these malignancies not only contributed to a better knowledge of the mechanisms responsible for tumor progression, but also offered the way for the discovery of new therapeutic targets. PMID:27583252

  10. Endothelial progenitor cells in hematologic malignancies.

    PubMed

    Testa, Ugo; Saulle, Ernestina; Castelli, Germana; Pelosi, Elvira

    2016-01-01

    Studies carried out in the last years have improved the understanding of the cellular and molecular mechanisms controlling angiogenesis during adult life in normal and pathological conditions. Some of these studies have led to the identification of some progenitor cells that sustain angiogenesis through indirect, paracrine mechanisms (hematopoietic angiogenic cells) and through direct mechanisms, i.e., through their capacity to generate a progeny of phenotypically and functionally competent endothelial cells [endothelial colony forming cells (ECFCs)]. The contribution of these progenitors to angiogenetic processes under physiological and pathological conditions is intensively investigated. Angiogenetic mechanisms are stimulated in various hematological malignancies, including chronic myeloid leukemia (CML), acute myeloid leukemia (AML), myelodysplastic syndromes and multiple myeloma, resulting in an increased angiogenesis that contributes to disease progression. In some of these conditions there is preliminary evidence that some endothelial cells could derive from the malignant clone, thus leading to the speculation that the leukemic cell derives from the malignant transformation of a hemangioblastic progenitor, i.e., of a cell capable of differentiation to the hematopoietic and to the endothelial cell lineages. Our understanding of the mechanisms underlying increased angiogenesis in these malignancies not only contributed to a better knowledge of the mechanisms responsible for tumor progression, but also offered the way for the discovery of new therapeutic targets. PMID:27583252

  11. EVOLUTION OF PROGENITORS FOR ELECTRON CAPTURE SUPERNOVAE

    SciTech Connect

    Takahashi, Koh; Umeda, Hideyuki; Yoshida, Takashi E-mail: umeda@astron.s.u-tokyo.ac.jp

    2013-07-01

    We provide progenitor models for electron capture supernovae (ECSNe) with detailed evolutionary calculation. We include minor electron capture nuclei using a large nuclear reaction network with updated reaction rates. For electron capture, the Coulomb correction of rates is treated and the contribution from neutron-rich isotopes is taken into account in each nuclear statistical equilibrium (NSE) composition. We calculate the evolution of the most massive super asymptotic giant branch stars and show that these stars undergo off-center carbon burning and form ONe cores at the center. These cores become heavier up to the critical mass of 1.367 M{sub Sun} and keep contracting even after the initiation of O+Ne deflagration. Inclusion of minor electron capture nuclei causes convective URCA cooling during the contraction phase, but the effect on the progenitor evolution is small. On the other hand, electron capture by neutron-rich isotopes in the NSE region has a more significant effect. We discuss the uniqueness of the critical core mass for ECSNe and the effect of wind mass loss on the plausibility of our models for ECSN progenitors.

  12. Complementation of sugary-1 phenotype in rice endosperm with the wheat isoamylase1 gene supports a direct role for isoamylase1 in amylopectin biosynthesis.

    PubMed

    Kubo, Akiko; Rahman, Sadequr; Utsumi, Yoshinori; Li, Zhongyi; Mukai, Yasuhiko; Yamamoto, Maki; Ugaki, Masashi; Harada, Kyuya; Satoh, Hikaru; Konik-Rose, Christine; Morell, Matthew; Nakamura, Yasunori

    2005-01-01

    To examine the role of isoamylase1 (ISA1) in amylopectin biosynthesis in plants, a genomic DNA fragment from Aegilops tauschii was introduced into the ISA1-deficient rice (Oryza sativa) sugary-1 mutant line EM914, in which endosperm starch is completely replaced by phytoglycogen. A. tauschii is the D genome donor of wheat (Triticum aestivum), and the introduced fragment effectively included the gene for ISA1 for wheat (TaISA1) that was encoded on the D genome. In TaISA1-expressing rice endosperm, phytoglycogen synthesis was substantially replaced by starch synthesis, leaving only residual levels of phytoglycogen. The levels of residual phytoglycogen present were inversely proportional to the expression level of the TaISA1 protein, although the level of pullulanase that had been reduced in EM914 was restored to the same level as that in the wild type. Small but significant differences were found in the amylopectin chain-length distribution, gelatinization temperatures, and A-type x-ray diffraction patterns of the starches from lines expressing TaISA1 when compared with wild-type rice starch, although in the first two parameters, the effect was proportional to the expression level of TaISA. The impact of expression levels of ISA1 on starch structure and properties provides support for the view that ISA1 is directly involved in the synthesis of amylopectin. PMID:15618430

  13. Analysis of the bread wheat genome using whole-genome shotgun sequencing.

    PubMed

    Brenchley, Rachel; Spannagl, Manuel; Pfeifer, Matthias; Barker, Gary L A; D'Amore, Rosalinda; Allen, Alexandra M; McKenzie, Neil; Kramer, Melissa; Kerhornou, Arnaud; Bolser, Dan; Kay, Suzanne; Waite, Darren; Trick, Martin; Bancroft, Ian; Gu, Yong; Huo, Naxin; Luo, Ming-Cheng; Sehgal, Sunish; Gill, Bikram; Kianian, Sharyar; Anderson, Olin; Kersey, Paul; Dvorak, Jan; McCombie, W Richard; Hall, Anthony; Mayer, Klaus F X; Edwards, Keith J; Bevan, Michael W; Hall, Neil

    2012-11-29

    Bread wheat (Triticum aestivum) is a globally important crop, accounting for 20 per cent of the calories consumed by humans. Major efforts are underway worldwide to increase wheat production by extending genetic diversity and analysing key traits, and genomic resources can accelerate progress. But so far the very large size and polyploid complexity of the bread wheat genome have been substantial barriers to genome analysis. Here we report the sequencing of its large, 17-gigabase-pair, hexaploid genome using 454 pyrosequencing, and comparison of this with the sequences of diploid ancestral and progenitor genomes. We identified between 94,000 and 96,000 genes, and assigned two-thirds to the three component genomes (A, B and D) of hexaploid wheat. High-resolution synteny maps identified many small disruptions to conserved gene order. We show that the hexaploid genome is highly dynamic, with significant loss of gene family members on polyploidization and domestication, and an abundance of gene fragments. Several classes of genes involved in energy harvesting, metabolism and growth are among expanded gene families that could be associated with crop productivity. Our analyses, coupled with the identification of extensive genetic variation, provide a resource for accelerating gene discovery and improving this major crop. PMID:23192148

  14. Characterizing the composition and evolution of homoeologous genomes in hexaploid wheat through BAC-end sequencing on chromosome 3B.

    PubMed

    Paux, Etienne; Roger, Delphine; Badaeva, Ekatherina; Gay, Georges; Bernard, Michel; Sourdille, Pierre; Feuillet, Catherine

    2006-11-01

    Bread wheat (Triticum aestivum) is one of the most important crops worldwide. However, because of its large, hexaploid, highly repetitive genome it is a challenge to develop efficient means for molecular analysis and genetic improvement in wheat. To better understand the composition and molecular evolution of the hexaploid wheat homoeologous genomes and to evaluate the potential of BAC-end sequences (BES) for marker development, we have followed a chromosome-specific strategy and generated 11 Mb of random BES from chromosome 3B, the largest chromosome of bread wheat. The sequence consisted of about 86% of repetitive elements, 1.2% of coding regions, and 13% remained unknown. With 1.2% of the sequence length corresponding to coding sequences, 6000 genes were estimated for chromosome 3B. New repetitive sequences were identified, including a Triticineae-specific tandem repeat (Fat) that represents 0.6% of the B-genome and has been differentially amplified in the homoeologous genomes before polyploidization. About 10% of the BES contained junctions between nested transposable elements that were used to develop chromosome-specific markers for physical and genetic mapping. Finally, sequence comparison with 2.9 Mb of random sequences from the D-genome of Aegilops tauschii suggested that the larger size of the B-genome is due to a higher content in repetitive elements. It also indicated which families of transposable elements are mostly responsible for differential expansion of the homoeologous wheat genomes during evolution. Our data demonstrate that BAC-end sequencing from flow-sorted chromosomes is a powerful tool for analysing the structure and evolution of polyploid and highly repetitive genomes. PMID:17010109

  15. Brazil wheat yield covariance model

    NASA Technical Reports Server (NTRS)

    Callis, S. L.; Sakamoto, C.

    1984-01-01

    A model based on multiple regression was developed to estimate wheat yields for the wheat growing states of Rio Grande do Sul, Parana, and Santa Catarina in Brazil. The meteorological data of these three states were pooled and the years 1972 to 1979 were used to develop the model since there was no technological trend in the yields during these years. Predictor variables were derived from monthly total precipitation, average monthly mean temperature, and average monthly maximum temperature.

  16. Aberrant mRNA processing of the maize Rp1-D rust resistance gene in wheat and barley.

    PubMed

    Ayliffe, Michael A; Steinau, Martin; Park, Robert F; Rooke, Lee; Pacheco, Maria G; Hulbert, Scot H; Trick, Harold N; Pryor, Anthony J

    2004-08-01

    The maize Rp1-D gene confers race-specific resistance against Puccinia sorghi (common leaf rust) isolates containing a corresponding avrRp1-D avirulence gene. An Rp1-D genomic clone and a similar Rp1-D transgene regulated by the maize ubiquitin promoter were transformed independently into susceptible maize lines and shown to confer Rp1-D resistance, demonstrating that this resistance can be transferred as a single gene. Transfer of these functional transgenes into wheat and barley did not result in novel resistances when these plants were challenged with isolates of wheat stem rust (P. graminis), wheat leaf rust (P. triticina), or barley leaf rust (P. hordei). Regardless of the promoter employed, low levels of gene expression were observed. When constitutive promoters were used for transgene expression, a majority of Rp1-D transcripts were truncated in the nucleotide binding site-encoding region by premature polyadenylation. This aberrant mRNA processing was unrelated to gene function because an inactive version of the gene also generated such transcripts. These data demonstrate that resistance gene transfer between species may not be limited only by divergence of signaling effector molecules and pathogen avirulence ligands, but potentially also by more fundamental gene expression and transcript processing limitations. PMID:15305606

  17. An intervarietal genetic linkage map of Indian bread wheat (Triticum aestivum L.) and QTL maps for some metric traits.

    PubMed

    Nalini, E; Bhagwat, S G; Jawali, N

    2007-06-01

    Bread wheat (Triticum aestivum L.) exhibits very narrow genetic diversity and hence there is high relatedness among cultivated varieties. However, a population generated from an intervarietal cross, with the parents differing in a large number of traits, could lead to the generation of QTL maps which will be useful in practice. In this report a genetic linkage map of wheat is constructed using a cross between two Indian bread wheat varieties: Sonalika and Kalyansona. The linkage map consisted of 236 markers and spanned a distance of 3639 cM, with 1211.2 cM for the A genome, 1669.2 cM for the B genome, 192.4 cM for the D genome and 566.2 cM for unassigned groups. Linkage analysis defined 37 linkage groups of which 24 were assigned to 17 chromosomes. The genetic map was used to identify QTLs by composite internal mapping (CIM) for three metric traits, viz. culm length (CL), flag leaf length (FLL) and flag leaf breadth (FLB). Of 25 QTLs identified in this study, 15 have not been reported previously. Multitrait CIM (MCIM) analysis was carried out for traits that were significantly correlated such as FLB-FLL and CL-FLB-FLL. Detection of a large number of QTLs for the three traits analysed suggests that in parent cultivars that are not too diverse, the differences at genetic level detected as polymorphisms may be mostly associated with QTLs for the observed differences. PMID:17894910

  18. 19 CFR 19.32 - Wheat manipulation; reconditioning.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Wheat manipulation; reconditioning. 19.32 Section... Bonded for the Storage of Wheat § 19.32 Wheat manipulation; reconditioning. (a) The mixing, blending, or commingling of imported wheat and domestic wheat, or of imported wheat of different classes and grades, as...

  19. Dough Rheology and Wet Milling of Hard Waxy Wheat Flours

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To realize the full potential of waxy wheat (Triticum aestivum L.), wet milling of waxy wheat flour to produce gluten and waxy wheat starch was investigated. Flours of six advanced lines of waxy hard wheats, one normal hard wheat (‘Karl 92’), and one partial waxy wheat (‘Trego’) were fractionated by...

  20. 19 CFR 19.32 - Wheat manipulation; reconditioning.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 1 2011-04-01 2011-04-01 false Wheat manipulation; reconditioning. 19.32 Section... Bonded for the Storage of Wheat § 19.32 Wheat manipulation; reconditioning. (a) The mixing, blending, or commingling of imported wheat and domestic wheat, or of imported wheat of different classes and grades, as...

  1. 19 CFR 19.32 - Wheat manipulation; reconditioning.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 1 2013-04-01 2013-04-01 false Wheat manipulation; reconditioning. 19.32 Section... Bonded for the Storage of Wheat § 19.32 Wheat manipulation; reconditioning. (a) The mixing, blending, or commingling of imported wheat and domestic wheat, or of imported wheat of different classes and grades, as...

  2. 19 CFR 19.32 - Wheat manipulation; reconditioning.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 19 Customs Duties 1 2014-04-01 2014-04-01 false Wheat manipulation; reconditioning. 19.32 Section... Bonded for the Storage of Wheat § 19.32 Wheat manipulation; reconditioning. (a) The mixing, blending, or commingling of imported wheat and domestic wheat, or of imported wheat of different classes and grades, as...

  3. 19 CFR 19.32 - Wheat manipulation; reconditioning.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 1 2012-04-01 2012-04-01 false Wheat manipulation; reconditioning. 19.32 Section... Bonded for the Storage of Wheat § 19.32 Wheat manipulation; reconditioning. (a) The mixing, blending, or commingling of imported wheat and domestic wheat, or of imported wheat of different classes and grades, as...

  4. Individual chromosome identification, chromosomal collinearity and genetic-physical integrated map in Gossypium darwinii and four D genome cotton species revealed by BAC-FISH.

    PubMed

    Gan, Yimei; Liu, Fang; Peng, Renhai; Wang, Chunying; Li, Shaohui; Zhang, Xiangdi; Wang, Yuhong; Wang, Kunbo

    2012-01-01

    The study was conducted on the individual chromosome identification in Gossypium darwinii (A(d)D(d)), G. klotzschianum (D(3k)), G. davidsonii (D(3d)), G. armourianum (D(2-1)) and G. aridum (D(4)) using a multi-probe fluorescence of in situ hybridization (FISH) system. Comparative analysis on their genetic maps with that of physical maps was made as well. The FISH probes used contained two sets of bacterial artificial chromosome (BAC) clones [one is specific to 26 individual chromosomes from A and D subgenomes of G. hirsutum (A(h) and D(h)) while the other is a D genome centromere-specific BAC clone 150D24], 45S and 5S rDNA clones. The results showed that all A(d) chromosomes were marked with the 13 A(h) chromosome-specific BAC clones, whilst all D(d), D(3k), D(3d), D(2-1) and D(4) chromosomes and chromosomal arms were identified with the 13 D(h) chromosome-specific BAC clones and the D genome centromere-specific BAC. According to the homology within D subgenomes which are between A (D) genome and A (D) subgenome, the systematic nomenclature for individual chromosome in the five species was established. The chromosomes of A (D) subgenomes in G. darwinii were named as A(d)01-A(d)13 (D(d)01-D(d)13). The chromosomes in D(3k), D(3d), D(2-1) and D(4) were named as D(3k)01-D(3k)13, D(3d)01-D(3d)13, D(2-1)01-D(2-1)13 and D(4)01-D(4)13, respectively. Based on the successful identification for individual chromosomes, 45S and 5S rDNA were located to the special chromosomes and chromosomal arms for all five species. And there appeared chromosomal collinearity from the BAC clones among different species by comparing BACs positions, which suggested that the majority of chromosome segment homology may exist between D genomes and D subgenome. Moreover, as the genetic map and physical map were integrated, the orientations of genetic maps for D(d) and D genomes of diploid cotton were established. The orientations of some of chromosomes in genetic maps (D(d)03, D(d)04, D(d)06, D(d)09

  5. Defining human dendritic cell progenitors by multiparametric flow cytometry

    PubMed Central

    Breton, Gaëlle; Lee, Jaeyop; Liu, Kang; Nussenzweig, Michel C

    2015-01-01

    Human dendritic cells (DCs) develop from progressively restricted bone marrow (BM) progenitors: these progenitor cells include granulocyte, monocyte and DC progenitor (GMDP) cells; monocyte and DC progenitor (MDP) cells; and common DC progenitor (CDP) and DC precursor (pre-DC) cells. These four DC progenitors can be defined on the basis of the expression of surface markers such as CD34 and hematopoietin receptors. In this protocol, we describe five multiparametric flow cytometry panels that can be used as a tool (i) to simultaneously detect or phenotype the four DC progenitors, (ii) to isolate DC progenitors to enable in vitro differentiation or (iii) to assess the in vitro differentiation and proliferation of DC progenitors. The entire procedure from isolation of cells to flow cytometry can be completed in 3–7 h. This protocol provides optimized antibody panels, as well as gating strategies, for immunostaining of BM and cord blood specimens to study human DC hematopoiesis in health, disease and vaccine settings. PMID:26292072

  6. Nutritional regulation of stem and progenitor cells in Drosophila

    PubMed Central

    Shim, Jiwon; Gururaja-Rao, Shubha; Banerjee, Utpal

    2013-01-01

    Stem cells and their progenitors are maintained within a microenvironment, termed the niche, through local cell-cell communication. Systemic signals originating outside the niche also affect stem cell and progenitor behavior. This review summarizes studies that pertain to nutritional effects on stem and progenitor cell maintenance and proliferation in Drosophila. Multiple tissue types are discussed that utilize the insulin-related signaling pathway to convey nutritional information either directly to these progenitors or via other cell types within the niche. The concept of systemic control of these cell types is not limited to Drosophila and may be functional in vertebrate systems, including mammals. PMID:24255094

  7. Cell culture: Progenitor cells from human brain after death

    NASA Astrophysics Data System (ADS)

    Palmer, Theo D.; Schwartz, Philip H.; Taupin, Philippe; Kaspar, Brian; Stein, Stuart A.; Gage, Fred H.

    2001-05-01

    Culturing neural progenitor cells from the adult rodent brain has become routine and is also possible from human fetal tissue, but expansion of these cells from postnatal and adult human tissue, although preferred for ethical reasons, has encountered problems. Here we describe the isolation and successful propagation of neural progenitor cells from human postmortem tissues and surgical specimens. Although the relative therapeutic merits of adult and fetal progenitor cells still need to be assessed, our results may extend the application of these progenitor cells in the treatment of neurodegenerative diseases.

  8. Defining human dendritic cell progenitors by multiparametric flow cytometry.

    PubMed

    Breton, Gaëlle; Lee, Jaeyop; Liu, Kang; Nussenzweig, Michel C

    2015-09-01

    Human dendritic cells (DCs) develop from progressively restricted bone marrow (BM) progenitors: these progenitor cells include granulocyte, monocyte and DC progenitor (GMDP) cells; monocyte and DC progenitor (MDP) cells; and common DC progenitor (CDP) and DC precursor (pre-DC) cells. These four DC progenitors can be defined on the basis of the expression of surface markers such as CD34 and hematopoietin receptors. In this protocol, we describe five multiparametric flow cytometry panels that can be used as a tool (i) to simultaneously detect or phenotype the four DC progenitors, (ii) to isolate DC progenitors to enable in vitro differentiation or (iii) to assess the in vitro differentiation and proliferation of DC progenitors. The entire procedure from isolation of cells to flow cytometry can be completed in 3-7 h. This protocol provides optimized antibody panels, as well as gating strategies, for immunostaining of BM and cord blood specimens to study human DC hematopoiesis in health, disease and vaccine settings. PMID:26292072

  9. Transformation of erythroid progenitors by viral and cellular tyrosine kinases.

    PubMed

    Beug, H; Schroeder, C; Wessely, O; Deiner, E; Meyer, S; Ischenko, I D; Hayman, M J

    1995-08-01

    Recently, two different normal avian erythroid progenitors were described. They differ in the receptor tyrosine kinases they express and in their ability to undergo self-renewal in culture. A common progenitor, termed stem cell factor (SCF) progenitor, expresses the receptor for avian SCF c-Kit, and undergoes short-term self-renewal when grown in the presence of avian SCF. A second progenitor, referred to as SCF/transforming growth factor-alpha progenitor, coexpresses c-Kit and the avian epidermal growth factor receptor homologue c-ErbB. These progenitors undergo sustained self-renewal when grown in the presence of transforming growth factor-alpha plus estradiol. The phenotype of the normal SCF/transforming growth factor-alpha progenitors closely corresponded to that of erythroid cells transformed by the tyrosine kinase oncogenes v-erbB or v-sea. This suggested that these cells, but not the SCF progenitors, would be the target cells for erythroblast transformation by these oncogenes. However, we demonstrate that both progenitor cells can be transformed by the v-erbB and v-sea oncogenes and also by the ligand-activated proto-oncogene product c-ErbB. We conclude that the target cell specificity of certain tyrosine kinase oncoproteins for erythroid cells is a reflection of their ability to provide signals for self-renewal that normally emanate from the endogenous c-ErbB protein. PMID:8547228

  10. Heritable, de novo resistance to leaf rust and other novel traits in selfed descendants of wheat responding to inoculation with wheat streak mosaic virus.

    PubMed

    Seifers, Dallas L; Haber, Steve; Martin, Terry J; McCallum, Brent D

    2014-01-01

    Stable resistance to infection with Wheat streak mosaic virus (WSMV) can be evolved de novo in selfing bread wheat lines subjected to cycles of WSMV inoculation and selection of best-performing plants or tillers. To learn whether this phenomenon might be applied to evolve resistance de novo to pathogens unrelated to WSMV, we examined the responses to leaf rust of succeeding generations of the rust- and WSMV-susceptible cultivar 'Lakin' following WSMV inoculation and derived rust-resistant sublines. After three cycles of the iterative protocol five plants, in contrast to all others, expressed resistance to leaf and stripe rust. A subset of descendant sublines of one of these, 'R1', heritably and uniformly expressed the new trait of resistance to leaf rust. Such sublines, into which no genes from a known source of resistance had been introgressed, conferred resistance to progeny of crosses with susceptible parents. The F1 populations produced from crosses between, respectively, susceptible and resistant 'Lakin' sublines 4-3-3 and 4-12-3 were not all uniform in their response to seedling inoculation with race TDBG. In seedling tests against TDBG and MKPS races the F2s from F1 populations that were uniformly resistant had 3∶1 ratios of resistant to susceptible individuals but the F2s from susceptible F1 progenitors were uniformly susceptible. True-breeding lines derived from resistant individuals in F2 populations were resistant to natural stripe and leaf rust inoculum in the field, while the 'Lakin' progenitor was susceptible. The next generation of six of the 'Lakin'-derived lines exhibited moderate to strong de novo resistance to stem rust races TPMK, QFCS and RKQQ in seedling tests while the 'Lakin' progenitor was susceptible. These apparently epigenetic effects in response to virus infection may help researchers fashion a new tool that expands the range of genetic resources already available in adapted germplasm. PMID:24497941