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Sample records for aegilops tauschii genome

  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. Genome-wide association study of drought-related resistance traits in Aegilops tauschii.

    PubMed

    Qin, Peng; Lin, Yu; Hu, Yaodong; Liu, Kun; Mao, Shuangshuang; Li, Zhanyi; Wang, Jirui; Liu, Yaxi; Wei, Yuming; Zheng, Youliang

    2016-07-01

    The D-genome progenitor of wheat (Triticum aestivum), Aegilops tauschii, possesses numerous genes for resistance to abiotic stresses, including drought. Therefore, information on the genetic architecture of A. tauschii can aid the development of drought-resistant wheat varieties. Here, we evaluated 13 traits in 373 A. tauschii accessions grown under normal and polyethylene glycol-simulated drought stress conditions and performed a genome-wide association study using 7,185 single nucleotide polymorphism (SNP) markers. We identified 208 and 28 SNPs associated with all traits using the general linear model and mixed linear model, respectively, while both models detected 25 significant SNPs with genome-wide distribution. Public database searches revealed several candidate/flanking genes related to drought resistance that were grouped into three categories according to the type of encoded protein (enzyme, storage protein, and drought-induced protein). This study provided essential information for SNPs and genes related to drought resistance in A. tauschii and wheat, and represents a foundation for breeding drought-resistant wheat cultivars using marker-assisted selection. PMID:27392238

  5. Genome-wide association study of drought-related resistance traits in Aegilops tauschii

    PubMed Central

    Qin, Peng; Lin, Yu; Hu, Yaodong; Liu, Kun; Mao, Shuangshuang; Li, Zhanyi; Wang, Jirui; Liu, Yaxi; Wei, Yuming; Zheng, Youliang

    2016-01-01

    Abstract The D-genome progenitor of wheat (Triticum aestivum), Aegilops tauschii, possesses numerous genes for resistance to abiotic stresses, including drought. Therefore, information on the genetic architecture of A. tauschii can aid the development of drought-resistant wheat varieties. Here, we evaluated 13 traits in 373 A. tauschii accessions grown under normal and polyethylene glycol-simulated drought stress conditions and performed a genome-wide association study using 7,185 single nucleotide polymorphism (SNP) markers. We identified 208 and 28 SNPs associated with all traits using the general linear model and mixed linear model, respectively, while both models detected 25 significant SNPs with genome-wide distribution. Public database searches revealed several candidate/flanking genes related to drought resistance that were grouped into three categories according to the type of encoded protein (enzyme, storage protein, and drought-induced protein). This study provided essential information for SNPs and genes related to drought resistance in A. tauschii and wheat, and represents a foundation for breeding drought-resistant wheat cultivars using marker-assisted selection. PMID:27560650

  6. Genome-wide association study of drought-related resistance traits in Aegilops tauschii.

    PubMed

    Qin, Peng; Lin, Yu; Hu, Yaodong; Liu, Kun; Mao, Shuangshuang; Li, Zhanyi; Wang, Jirui; Liu, Yaxi; Wei, Yuming; Zheng, Youliang

    2016-01-01

    The D-genome progenitor of wheat (Triticum aestivum), Aegilops tauschii, possesses numerous genes for resistance to abiotic stresses, including drought. Therefore, information on the genetic architecture of A. tauschii can aid the development of drought-resistant wheat varieties. Here, we evaluated 13 traits in 373 A. tauschii accessions grown under normal and polyethylene glycol-simulated drought stress conditions and performed a genome-wide association study using 7,185 single nucleotide polymorphism (SNP) markers. We identified 208 and 28 SNPs associated with all traits using the general linear model and mixed linear model, respectively, while both models detected 25 significant SNPs with genome-wide distribution. Public database searches revealed several candidate/flanking genes related to drought resistance that were grouped into three categories according to the type of encoded protein (enzyme, storage protein, and drought-induced protein). This study provided essential information for SNPs and genes related to drought resistance in A. tauschii and wheat, and represents a foundation for breeding drought-resistant wheat cultivars using marker-assisted selection. PMID:27560650

  7. Gene Space Dynamics during the Evolution of Aegilops tauschii, Brachypodium distachyon, Oryza sativa, and Sorghum bicolor Genomes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nine different regions totaling 9.7 Mb of the 4.02 Gb Aegilops tauschii genome were sequenced using the Sanger sequencing technology and compared with orthologous Brachypodium distachyon, Oryza sativa (rice) and Sorghum bicolor (sorghum) genomic sequences. The ancestral gene content in these regio...

  8. Genome-wide identification of novel genetic markers from RNA sequencing assembly of diverse Aegilops tauschii accessions.

    PubMed

    Nishijima, Ryo; Yoshida, Kentaro; Motoi, Yuka; Sato, Kazuhiro; Takumi, Shigeo

    2016-08-01

    The wild species in the Triticeae tribe are tremendous resources for crop breeding due to their abundant natural variation. However, their huge and highly repetitive genomes have hindered the establishment of physical maps and the completeness of their genome sequences. To develop molecular markers for the efficient utilization of their valuable traits while avoiding their genome complexity, we assembled RNA sequences of ten representative accessions of Aegilops tauschii, the progenitor of the wheat D genome, and estimated single nucleotide polymorphisms (SNPs) and insertions/deletions (indels). The deduced unigenes were anchored to the chromosomes of Ae. tauschii and barley. The SNPs and indels in the anchored unigenes, covering entire chromosomes, were sufficient for linkage map construction, even in combinations between the genetically closest accessions. Interestingly, the resolution of SNP and indel distribution on barley chromosomes was slightly higher than on Ae. tauschii chromosomes. Since barley chromosomes are regarded as virtual chromosomes of Triticeae species, our strategy allows capture of genetic markers arranged on the chromosomes in order based on the conserved synteny. The resolution of these genetic markers will be comparable to that of the Ae. tauschii whose draft genome sequence is available. Our procedure should be applicable to marker development for Triticeae species, which have no draft sequences available. PMID:27142109

  9. Physical mapping of a large plant genome using global high-information-content-fingerprinting: the distal region of the wheat ancestor Aegilops tauschii 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 the hexaploid bread wheat. The diploid ancestor of wheat genome, Aegilops tauschii, is used as a resource for wheat...

  10. 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...

  11. 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

  12. 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

  13. 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

  14. 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

  15. 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...

  16. 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

  17. Strategy for exploiting exotic germplasm using genetic, morphological, and environmental diversity: the Aegilops tauschii Coss. example.

    PubMed

    Jones, H; Gosman, N; Horsnell, R; Rose, G A; Everest, L A; Bentley, A R; Tha, S; Uauy, C; Kowalski, A; Novoselovic, D; Simek, R; Kobiljski, B; Kondic-Spika, A; Brbaklic, L; Mitrofanova, O; Chesnokov, Y; Bonnett, D; Greenland, A

    2013-07-01

    Hexaploid bread wheat evolved from a rare hybridisation, which resulted in a loss of genetic diversity in the wheat D-genome with respect to the ancestral donor, Aegilops tauschii. Novel genetic variation can be introduced into modern wheat by recreating the above hybridisation; however, the information associated with the Ae. tauschii accessions in germplasm collections is limited, making rational selection of accessions into a re-synthesis programme difficult. We describe methodologies to identify novel diversity from Ae. tauschii accessions that combines Bayesian analysis of genotypic data, sub-species diversity and geographic information that summarises variation in climate and habitat at the collection point for each accession. Comparisons were made between diversity discovered amongst a panel of Ae. tauschii accessions, bread wheat varieties and lines from the CIMMYT synthetic hexaploid wheat programme. The selection of Ae. tauschii accessions based on differing approaches had significant effect on diversity within each set. Our results suggest that a strategy that combines several criteria will be most effective in maximising the sampled variation across multiple parameters. The analysis of multiple layers of variation in ex situ Ae. tauschii collections allows for an informed and rational approach to the inclusion of wild relatives into crop breeding programmes. PMID:23558983

  18. 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

    Background Hybrid speciation is classified into homoploid and polyploid based on ploidy level. Common wheat is an allohexaploid species that originated from a naturally occurring interploidy cross between tetraploid wheat and diploid wild wheat Aegilops tauschii Coss. Aegilops tauschii provides wide naturally occurring genetic variation. Sometimes its triploid hybrids with tetraploid wheat show the following four types of hybrid growth abnormalities: types II and III hybrid necrosis, hybrid chlorosis, and severe growth abortion. The growth abnormalities in the triploid hybrids could act as postzygotic hybridization barriers to prevent formation of hexaploid wheat. Methodology/Principal Findings Here, we report on the geographical and phylogenetic distribution of Ae. tauschii accessions inducing the hybrid growth abnormalities and showed that they are widely distributed across growth habitats in Ae. tauschii. Molecular and cytological characterization of the type III necrosis phenotype was performed. The hybrid abnormality causing accessions were widely distributed across growth habitats in Ae. tauschii. Transcriptome analysis showed that a number of defense-related genes such as pathogenesis-related genes were highly up-regulated in the type III necrosis lines. Transmission electron microscope observation revealed that cell death occurred accompanied by generation of reactive oxygen species in leaves undergoing type III necrosis. The reduction of photosynthetic activity occurred prior to the appearance of necrotic symptoms on the leaves exhibiting hybrid necrosis. Conclusions/Significance Taking these results together strongly suggests that an autoimmune response might be triggered by intergenomic incompatibility between the tetraploid wheat and Ae. tauschii genomes in type III necrosis, and that genetically programmed cell death could be regarded as a hypersensitive response-like cell death similar to that observed in Arabidopsis intraspecific and Nicotiana

  19. 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...

  20. 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

  1. Annotation-based genome-wide SNP discovery in the large and complex Aegilops tauschii genome using next-generation sequencing without a reference genome sequence

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An annotation-based, genome-wide SNP discovery pipeline is reported using NGS data for large and complex genomes without a reference genome sequence. Roche 454 shotgun reads with low genome coverage of one genotype are annotated in order to distinguish single-copy sequences and repeat junctions fr...

  2. Harnessing NGS and Big Data Optimally: Comparison of miRNA Prediction from Assembled versus Non-assembled Sequencing Data--The Case of the Grass Aegilops tauschii Complex Genome.

    PubMed

    Budak, Hikmet; Kantar, Melda

    2015-07-01

    MicroRNAs (miRNAs) are small, endogenous, non-coding RNA molecules that regulate gene expression at the post-transcriptional level. As high-throughput next generation sequencing (NGS) and Big Data rapidly accumulate for various species, efforts for in silico identification of miRNAs intensify. Surprisingly, the effect of the input genomics sequence on the robustness of miRNA prediction was not evaluated in detail to date. In the present study, we performed a homology-based miRNA and isomiRNA prediction of the 5D chromosome of bread wheat progenitor, Aegilops tauschii, using two distinct sequence data sets as input: (1) raw sequence reads obtained from 454-GS FLX Titanium sequencing platform and (2) an assembly constructed from these reads. We also compared this method with a number of available plant sequence datasets. We report here the identification of 62 and 22 miRNAs from raw reads and the assembly, respectively, of which 16 were predicted with high confidence from both datasets. While raw reads promoted sensitivity with the high number of miRNAs predicted, 55% (12 out of 22) of the assembly-based predictions were supported by previous observations, bringing specificity forward compared to the read-based predictions, of which only 37% were supported. Importantly, raw reads could identify several repeat-related miRNAs that could not be detected with the assembly. However, raw reads could not capture 6 miRNAs, for which the stem-loops could only be covered by the relatively longer sequences from the assembly. In summary, the comparison of miRNA datasets obtained by these two strategies revealed that utilization of raw reads, as well as assemblies for in silico prediction, have distinct advantages and disadvantages. Consideration of these important nuances can benefit future miRNA identification efforts in the current age of NGS and Big Data driven life sciences innovation. PMID:26061358

  3. 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...

  4. Radiation hybrid maps of D-genome of Aegilops tauschii and their application in sequence assembly of large and complex plant genomes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The large and complex genome of bread wheat (Triticum aestivum L., ~17 Gb) requires high-resolution genome maps saturated with ordered markers to assist in anchoring and orienting BAC contigs/ sequence scaffolds for whole genome sequence assembly. Radiation hybrid (RH) mapping has proven to be an e...

  5. Rapid genome mapping in nano channel array for highly complete and accurate de novo sequence assembly of the complex Aegilops tauschii genome

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Next-generation sequencing (NGS) technologies have enabled high-throughput and low-cost generation of sequence data; however, de novo genome assembly remains a great challenge, particularly for large genomes. NGS short reads are often insufficient to create large contigs that span repeat sequences...

  6. Effective transfer of chromosomes carrying leaf rust resistance genes from Aegilops tauschii Coss. into hexaploid triticale (X Triticosecale Witt.) using Ae. tauschii × Secale cereale amphiploid forms.

    PubMed

    Kwiatek, Michał; Majka, Maciej; Wiśniewska, Halina; Apolinarska, Barbara; Belter, Jolanta

    2015-05-01

    This paper shows the results of effective uses of a molecular cytogenetics toolbox and molecular marker to transfer leaf rust resistance genes from Aegilops tauschii × Secale cereale (DDRR, 2n = 4x = 28) amphiploid forms to triticale cv. Bogo (AABBRR, 2n = 6x = 42). The molecular markers of resistance genes and in situ hybridization analysis of mitotic metaphase of root meristems confirmed the stable inheritance of chromosome 3D segments carrying Lr32 from the BC2F2 to the BC2F5 generation of (Ae. tauschii × S. cereale) × triticale hybrids. The chromosome pairing analysis during metaphase I of meiosis of BC2F4 and BC2F5 hybrids showed increasing regular bivalent formation of 3D chromosome pairs and decreasing number of univalents in subsequent generations. The results indicate that using amphiploid forms as a bridge between wild and cultivated forms can be a successful technology to transfer the D-genome chromatin carrying leaf rust resistance genes into triticale. PMID:25502891

  7. Stem rust, tan spot, Stagonospora nodorum blotch, and Hessian fly resistance in Langdon durum - Aegilops tauschii synethetic hexaploid wheat lines.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Diseases and pests of wheat incur serious yield and quality losses to wheat grown worldwide. In the current study, we tested synthetic hexaploid wheat (SHW) lines developed from various Aegilops tauschii lines crossed with the tetraploid durum wheat line Langdon. The SHW lines were tested along wi...

  8. MlNCD1: A novel Aegilops tauschii derived powdery mildew resistance gene identified in common wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Powdery mildew is a major fungal disease in wheat, especially in cool maritime climates. A novel Aegilops tauschii derived wheat powdery mildew resistance gene present in the germplasm line NC96BGTD1 was genetically characterized as a monogenic trait in field trials using F2 and F4-derived lines fr...

  9. [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

  10. 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...

  11. [Genetic analysis and SSR mapping on an new stem stripe rust resistance gene YrY206 in Aegilops tauschii].

    PubMed

    Zhang, Haiquan; Lang, Jie; Ma, Shuqin; Zhang, Baoshi

    2008-08-01

    A wheat stripe rust resistance gene was screened out from Aegilops tauschii which is relative genera of wheat species, broadening the genetic basis of the anti-disease character of wheat species. By hybridizing diversed Ae. Tauschii species, which is either resistant or susceptible to wheat stripe rust, a dominant wheat stripe rust resistance gene was detected from Ae. Tauschii (Coss.) Schmal Y206. The novel gene was temporarily designated as YrY206. By bulk segregation analysis, four microsatellite markers Wmc11a, Xgwm71c, Xgwm161 and Xgwm183 were found to be linked to YrY206 with genetic distances of 4.0, 3.3, 1.5 and 9.3 cM, respectively. According to the locations of the linked markers, the resistance gene was located on chromosome 3DS. Based on the chromosomal location and the resistance pattern of the gene, YrY206 should be a novel stripe rust resistance gene. PMID:18998554

  12. Chloroplast and nuclear microsatellite analysis of Aegilops cylindrica.

    PubMed

    Gandhi, Harish T; Vales, M Isabel; Watson, Christy J W; Mallory-Smith, Carol A; Mori, Naoki; Rehman, Maqsood; Zemetra, Robert S; Riera-Lizarazu, Oscar

    2005-08-01

    Aegilops cylindrica Host (2n = 4x = 28, genome CCDD) is an allotetraploid formed by hybridization between the diploid species Ae. tauschii Coss. (2n = 2x = 14, genome DD) and Ae. markgrafii (Greuter) Hammer (2n = 2x = 14, genome CC). Previous research has shown that Ae. tauschii contributed its cytoplasm to Ae. cylindrica. However, our analysis with chloroplast microsatellite markers showed that 1 of the 36 Ae. cylindrica accessions studied, TK 116 (PI 486249), had a plastome derived from Ae. markgrafii rather than Ae. tauschii. Thus, Ae. markgrafii has also contributed its cytoplasm to Ae. cylindrica. Our analysis of chloroplast and nuclear microsatellite markers also suggests that D-type plastome and the D genome in Ae. cylindrica were closely related to, and were probably derived from, the tauschii gene pool of Ae. tauschii. A determination of the likely source of the C genome and the C-type plastome in Ae. cylindrica was not possible. PMID:15986256

  13. Molecular survey of Tamyb10-1 genes and their association with grain colour and germinability in Chinese wheat and Aegilops tauschii.

    PubMed

    Dong, Zhong Dong; Chen, Jie; Li, Ting; Chen, Feng; Cui, Dang Qun

    2015-09-01

    To investigate allelic variation of Myb10-1 genes in Chinese wheat and to examine its association with germination level in wheat, a total of 582 Chinese bread wheat cultivars and 110 Aegilops tauschii accessions were used to identify allelic variations of three Myb10-1 genes. Identification results indicated that there is a novel Tamyb10-B1 allele, designated Tamyb10-B1c, in the five Chinese landraces. The Tamyb10-B1c possibly has a large deletion including Tamyb10-B1 gene. There are three novel Tamyb10-D1 alleles (Aetmyb10-D1c, Aetmyb10-D1d and Aetmyb10-D1e) that were discovered in Aegilops tauschii. Of them, Aetmyb10-D1c allele possessed a 104-bp deletion and this resulted in a frame shift in the open reading frame of the Aetmyb10-D1 gene. AETMYB10-D1d and AETMYB10-D1e proteins possessed three and two different amino acids when compared with TAMYB10-D1b protein, respectively. Association of Tamyb10-1 allelic variation with grain germination level indicated that all five allelic combinations with red grains showed a significantly higher GP (germination percentage) and GI (germination index) values than those of white-grained Tamyb10-A1a/Tamyb10-B1a/Tamyb10-D1a genotype after storing it for one year. Moreover, the Tamyb10-A1b/Tamyb10-B1c/Tamyb10-D1b genotype possesses the significantly highest GP and GI among the six different Tamyb10-1 combinations. This study could provide useful information for wheat breeding programme in terms of grain colour and germination level. PMID:26440084

  14. Quantification and organization of WIS2-1A and BARE-1 retrotransposons in different genomes of Triticum and Aegilops species.

    PubMed

    Pagnotta, Mario Augusto; Mondini, Linda; Porceddu, Enrico

    2009-09-01

    A real-time PCR approach was adopted and optimized to estimate and compare, through a relative quantification, the copy number of WIS2-1A and BARE-1 retrotransposons. The aim of this approach was to identify and quantify the presence of these retrotransposons in Triticum and Aegilops species, and to understand better the genome organization of these retroelements. The species were selected to assess and compare the evolution of the different types of genomes between the more recent species such as the diploid Triticum monococcum, tetraploid T. dicoccon and hexaploid T. spelta, and the corresponding genome donors of the ancient diploids Aegilops (Ae. speltoides, Ae. tauschii, Ae. sharonensis and Ae. bicornis) and T. urartu. The results of this study indicated the presence of great variation in copy number both within and among species, and the existence of a non-linear relationship between retrotransposon copy number and ploidy level. For WIS2-1A, as expected, T. monococcum showed the lowest copy number which instead was similar in T. dicoccon and T. spelta; also T. urartu (AA), Ae. speltoides (BB) and Ae. tauschii (DD) showed a higher WIS2-1A copy number. Similar results were observed for BARE-1 retroelements except for Ae. tauschii which as in T. monococcum showed lower retroelements content; a similar content for T. dicoccon and T. urartu, whereas a higher number was found in T. spelta and Ae. speltoides. The results presented here are in accord with previous studies and contribute to unravelling the structure and evolution of polyploidy and repetitive genomes. PMID:19543749

  15. Genome structure of introgressive lines Triticum aestivum/Aegilops sharonensis.

    PubMed

    Antonyuk, M Z; Bodylyova, M V; Ternovskaya, T K

    2009-01-01

    The lines Triticum aestivum/Aegilops sharonensis were explored in regard to the presence of introgressions in the line genomes, their amount and belonging to definite homoeologic group. The results of studying of chromosome associations in M1 of pollen mother celles in the hybrids between the lines with each other and with recurrent common wheat genotype Avrora were compared with the data of the line assessment for the chromosomal biochemical and morphological markers. 26 lines were distinguished between six groups with specific genome rearrangement regard to recurrent genotype. PMID:20458978

  16. Identification of CBF14 and NAC2 Genes in Aegilops tauschii Associated with Resistance to Freezing Stress.

    PubMed

    Masoomi-Aladizgeh, Farhad; Aalami, Ali; Esfahani, Masoud; Aghaei, Mohamad Jaafar; Mozaffari, Khadijeh

    2015-06-01

    Low temperature as one of the most important environmental factors limits the productivity of plants across the world. Aegilops, as a wild species of Poaceae, contains low temperature-responsive genes. In this study, we analyzed morphological (wilting, chlorosis, and recovery) and physiological (ion leakage) characteristics to identification of a cold-tolerant genotype. In this experiment, we introduced two transcription factors (TFs) in Aegilops species for the first time. Bioinformatics analysis demonstrated that our nucleotide sequences have high similarity with CBF14 (C-repeat-binding factor) and NAC2 (NAM, ATAF, and CUC) in Triticum aestivum. Based on the physiological and morphological data, one genotype (Aladizgeh) was identified as the most resistant genotype which was selected for further gene expression analysis. The real-time PCR results indicated that the CBF14 gene was not expressed 3 h following cold treatment, but the highest expression was observed after 6, 12, and 24 h of cold treatment; however, a sudden decrease was observed in its expression after 30 h. The NAC2 gene also was not expressed 3 h after cold stress, but the highest expression was at 24 h and similar to the CBF14 gene; its expression suddenly decreased after 30 h. Our results indicated that this genotype can tolerate -4 °C for 3 h, but the CBF14 and NAC2 genes were activated when treated for longer durations. Expression of TFs studied in this experiment had decreased after 30 h, in which cell death seems to be the important reason. PMID:25900437

  17. Accelerated senescence and enhanced disease resistance in hybrid chlorosis lines derived from interspecific crosses between tetraploid wheat and Aegilops tauschii.

    PubMed

    Nakano, Hiroki; Mizuno, Nobuyuki; Tosa, Yukio; Yoshida, Kentaro; Park, Pyoyun; Takumi, Shigeo

    2015-01-01

    Hybrid chlorosis, a type of hybrid incompatibility, has frequently been reported in inter- and intraspecific crosses of allopolyploid wheat. In a previous study, we reported some types of growth abnormalities such as hybrid necrosis and observed hybrid chlorosis with mild or severe abnormalities in wheat triploids obtained in crosses between tetraploid wheat cultivar Langdon and four Ae. tauschii accessions and in their derived synthetic hexaploids. However, the molecular mechanisms underlying hybrid chlorosis are not well understood. Here, we compared cytology and gene expression in leaves to characterize the abnormal growth in wheat synthetics showing mild and severe chlorosis. In addition, we compared disease resistance to wheat blast fungus. In total 55 and 105 genes related to carbohydrate metabolism and 53 and 89 genes for defense responses were markedly up-regulated in the mild and severe chlorosis lines, respectively. Abnormal chloroplasts formed in the mesophyll cells before the leaves yellowed in the hybrid chlorosis lines. The plants with mild chlorosis showed increased resistance to wheat blast and powdery mildew fungi, although significant differences only in two, third internode length and maturation time, out of the examined agricultural traits were found between the wild type and plants showing mild chlorosis. These observations suggest that senescence might be accelerated in hybrid chlorosis lines of wheat synthetics. Moreover, in wheat synthetics showing mild chlorosis, the negative effects on biomass can be minimized, and they may show substantial fitness under pathogen-polluted conditions. PMID:25806790

  18. Accelerated Senescence and Enhanced Disease Resistance in Hybrid Chlorosis Lines Derived from Interspecific Crosses between Tetraploid Wheat and Aegilops tauschii

    PubMed Central

    Tosa, Yukio; Yoshida, Kentaro; Park, Pyoyun; Takumi, Shigeo

    2015-01-01

    Hybrid chlorosis, a type of hybrid incompatibility, has frequently been reported in inter- and intraspecific crosses of allopolyploid wheat. In a previous study, we reported some types of growth abnormalities such as hybrid necrosis and observed hybrid chlorosis with mild or severe abnormalities in wheat triploids obtained in crosses between tetraploid wheat cultivar Langdon and four Ae. tauschii accessions and in their derived synthetic hexaploids. However, the molecular mechanisms underlying hybrid chlorosis are not well understood. Here, we compared cytology and gene expression in leaves to characterize the abnormal growth in wheat synthetics showing mild and severe chlorosis. In addition, we compared disease resistance to wheat blast fungus. In total 55 and 105 genes related to carbohydrate metabolism and 53 and 89 genes for defense responses were markedly up-regulated in the mild and severe chlorosis lines, respectively. Abnormal chloroplasts formed in the mesophyll cells before the leaves yellowed in the hybrid chlorosis lines. The plants with mild chlorosis showed increased resistance to wheat blast and powdery mildew fungi, although significant differences only in two, third internode length and maturation time, out of the examined agricultural traits were found between the wild type and plants showing mild chlorosis. These observations suggest that senescence might be accelerated in hybrid chlorosis lines of wheat synthetics. Moreover, in wheat synthetics showing mild chlorosis, the negative effects on biomass can be minimized, and they may show substantial fitness under pathogen-polluted conditions. PMID:25806790

  19. 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

  20. Expansion of the gamma-gliadin gene family in Aegilops and Triticum

    PubMed Central

    2012-01-01

    Background The gamma-gliadins are considered to be the oldest of the gliadin family of storage proteins in Aegilops/Triticum. However, the expansion of this multigene family has not been studied in an evolutionary perspective. Results We have cloned 59 gamma-gliadin genes from Aegilops and Triticum species (Aegilops caudata L., Aegilops comosa Sm. in Sibth. & Sm., Aegilops mutica Boiss., Aegilops speltoides Tausch, Aegilops tauschii Coss., Aegilops umbellulata Zhuk., Aegilops uniaristata Vis., and Triticum monococcum L.) representing eight different genomes: Am, B/S, C, D, M, N, T and U. Overall, 15% of the sequences contained internal stop codons resulting in pseudogenes, but this percentage was variable among genomes, up to over 50% in Ae. umbellulata. The most common length of the deduced protein, including the signal peptide, was 302 amino acids, but the length varied from 215 to 362 amino acids, both obtained from Ae. speltoides. Most genes encoded proteins with eight cysteines. However, all Aegilops species had genes that encoded a gamma-gliadin protein of 302 amino acids with an additional cysteine. These conserved nine-cysteine gamma-gliadins may perform a specific function, possibly as chain terminators in gluten network formation in protein bodies during endosperm development. A phylogenetic analysis of gamma-gliadins derived from Aegilops and Triticum species and the related genera Lophopyrum, Crithopsis, and Dasypyrum showed six groups of genes. Most Aegilops species contained gamma-gliadin genes from several of these groups, which also included sequences from the genera Lophopyrum, Crithopsis, and Dasypyrum. Hordein and secalin sequences formed separate groups. Conclusions We present a model for the evolution of the gamma-gliadins from which we deduce that the most recent common ancestor (MRCA) of Aegilops/Triticum-Dasypyrum-Lophopyrum-Crithopsis already had four groups of gamma-gliadin sequences, presumably the result of two rounds of duplication of

  1. 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

  2. Genome Comparisons Reveal a Dominant Mechanism of Chromosome Number Reduction in Grasses and Accelerated Genome Evolution in Triticeae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Single nucleotide polymorphism was employed in the construction of a high-resolution, expressed sequence tag (EST) map of Aegilops tauschii, the diploid source of the wheat D genome. Comparison of the map with the rice and sorghum genome sequences revealed 50 inversions and translocations; 2, 8, and...

  3. 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

  4. [Analysis of 5S rDNA changes in synthetic allopolyploids Triticum x Aegilops].

    PubMed

    Shcherban', A B; Sergeeva, E M; Badaeva, E D; Salina, E A

    2008-01-01

    By the example of three synthetic allopolyploids: Aegilops sharonensis x Ae. umbellulata (2n =28), Triticum urartu x Ae. tauschii (2n =28), T. dicoccoides x Ae. tauschii (2n =42) the 5S rDNA changes at the early stage of allopolyploidization were investigated. Using fluorescent in situ hybridization (FISH), the quantitative changes affecting the separate loci of one of the parental genomes were revealed in plants of S3 generation of each hybrid combination. Souther hybridization with genomic DNA of allopolyploid T. urartu x Ae. tauschii (TMU38 x TQ27) revealed lower intensity of the fragments from Ae. tauschii compared with the T. urartu fragments. It may be confirmation of the reduction of signal on 1D chromosome that was revealed in this hybrid using FISH. Both appearance of a new 5S rDNA fragments and full disappearance of fragments from parental species were not showed by Southern hybridization, as well as PCR-analysis of 5-15 plants of S2-S3 generations. The changes were not found under comparison of primary structure of nine 5S rDNA sequences of allopolyploid TMU38 x TQ27 with analogous sequences from parental species genomes. The observable similarity by FISH results of one of the studied synthetic allopolyploids with natural allopolyploid of similar genome composition indicates the early formation of unique for each allopolyploid 5S rDNA organization. PMID:18856060

  5. 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

  6. B Chromosomes of Aegilops speltoides Are Enriched in Organelle Genome-Derived Sequences

    PubMed Central

    Ruban, Alevtina; Fuchs, Jörg; Marques, André; Schubert, Veit; Soloviev, Alexander; Raskina, Olga; Badaeva, Ekaterina; Houben, Andreas

    2014-01-01

    B chromosomes (Bs) are dispensable components of the genome exhibiting non-Mendelian inheritance. Chromosome counts and flow cytometric analysis of the grass species Aegilops speltoides revealed a tissue-type specific distribution of the roughly 570 Mbp large B chromosomes. To address the question whether organelle-to-nucleus DNA transfer is a mechanism that drives the evolution of Bs, in situ hybridization was performed with labelled organellar DNA. The observed B-specific accumulation of chloroplast- and mitochondria-derived sequences suggests a reduced selection against the insertion of organellar DNA in supernumerary chromosomes. The distribution of B-localised organellar-derived sequences and other sequences differs between genotypes of different geographical origins. PMID:24587288

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

    PubMed

    Tsunewaki, Koichiro; Mori, Naoki; Takumi, Shigeo

    2014-01-01

    In the course of reconstructing Aegilops caudata from its own genome (CC) and its plasmon, which had passed half a century in common wheat (genome AABBDD), we produced alloplasmic Ae. cylindrica (genome CCDD) with the plasmon of Ae. caudata. This line, designated (caudata)-CCDD, was found to express male sterility in its second substitution backcross generation (SB2) of (caudata)-AABBCCDD pollinated three times with the Ae. cylindrica pollen. We repeatedly backcrossed these SB2 plants with the Ae. cylindrica pollen until the SB5 generation, and SB5F2 progeny were produced by self-pollination of the SB5 plants. Thirteen morphological and physiological characters, including pollen and seed fertilities, of the (caudata)-CCDD SB5F2 were compared with those of the euplasmic Ae. cylindrica. The results indicated that the male sterility expressed by (caudata)-CCDD was due to genetic incompatibility between the Ae. cylindrica genome and Ae. caudata plasmon that did not affect any other characters of Ae. cylindrica. Also, we report that the genome integrity functions in keeping the univalent transmission rate high. PMID:25832746

  8. Genetic compensation abilities of Aegilops speltoides chromosomes for homoeologous B-genome chromosomes of polyploid wheat in disomic S(B) chromosome substitution lines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The S genome of Aegilops speltoides is closely related to the B and G genomes of polyploid wheats. However, little work has been reported on the genetic relationships between the S-genome and B-genome chromosomes of polyploid wheat. Here we report the isolation of a set of disomic substitutions (DS)...

  9. Allopolyploidy-induced rapid genome evolution in the wheat (Aegilops-Triticum) group.

    PubMed

    Ozkan, H; Levy, A A; Feldman, M

    2001-08-01

    To better understand genetic events that accompany allopolyploid formation, we studied the rate and time of elimination of eight DNA sequences in F1 hybrids and newly formed allopolyploids of Aegilops and TRITICUM: In total, 35 interspecific and intergeneric F1 hybrids and 22 derived allopolyploids were analyzed and compared with their direct parental plants. The studied sequences exist in all the diploid species of the Triticeae but occur in only one genome, either in one homologous pair (chromosome-specific sequences [CSSs]) or in several pairs of the same genome (genome-specific sequences [GSSs]), in the polyploid wheats. It was found that rapid elimination of CSSs and GSSs is a general phenomenon in newly synthesized allopolyploids. Elimination of GSSs was already initiated in F1 plants and was completed in the second or third allopolyploid generation, whereas elimination of CSSs started in the first allopolyploid generation and was completed in the second or third generation. Sequence elimination started earlier in allopolyploids whose genome constitution was analogous to natural polyploids compared with allopolyploids that do not occur in nature. Elimination is a nonrandom and reproducible event whose direction was determined by the genomic combination of the hybrid or the allopolyploid. It was not affected by the genotype of the parental plants, by their cytoplasm, or by the ploidy level, and it did not result from intergenomic recombination. Allopolyploidy-induced sequence elimination occurred in a sizable fraction of the genome and in sequences that were apparently noncoding. This finding suggests a role in augmenting the differentiation of homoeologous chromosomes at the polyploid level, thereby providing the physical basis for the diploid-like meiotic behavior of newly formed allopolyploids. In our view, this rapid genome adjustment may have contributed to the successful establishment of newly formed allopolyploids as new species. PMID:11487689

  10. 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

  11. Genome comparisons reveal a dominant mechanism of chromosome number reduction in grasses and accelerated genome evolution in Triticeae

    PubMed Central

    Luo, M. C.; Deal, K. R.; Akhunov, E. D.; Akhunova, A. R.; Anderson, O. D.; Anderson, J. A.; Blake, N.; Clegg, M. T.; Coleman-Derr, D.; Conley, E. J.; Crossman, C. C.; Dubcovsky, J.; Gill, B. S.; Gu, Y. Q.; Hadam, J.; Heo, H. Y.; Huo, N.; Lazo, G.; Ma, Y.; Matthews, D. E.; McGuire, P. E.; Morrell, P. L.; Qualset, C. O.; Renfro, J.; Tabanao, D.; Talbert, L. E.; Tian, C.; Toleno, D. M.; Warburton, M. L.; You, F. M.; Zhang, W.; Dvorak, J.

    2009-01-01

    Single-nucleotide polymorphism was used in the construction of an expressed sequence tag map of Aegilops tauschii, the diploid source of the wheat D genome. Comparisons of the map with the rice and sorghum genome sequences revealed 50 inversions and translocations; 2, 8, and 40 were assigned respectively to the rice, sorghum, and Ae. tauschii lineages, showing greatly accelerated genome evolution in the large Triticeae genomes. The reduction of the basic chromosome number from 12 to 7 in the Triticeae has taken place by a process during which an entire chromosome is inserted by its telomeres into a break in the centromeric region of another chromosome. The original centromere–telomere polarity of the chromosome arms is maintained in the new chromosome. An intrachromosomal telomere–telomere fusion resulting in a pericentric translocation of a chromosome segment or an entire arm accompanied or preceded the chromosome insertion in some instances. Insertional dysploidy has been recorded in three grass subfamilies and appears to be the dominant mechanism of basic chromosome number reduction in grasses. A total of 64% and 66% of Ae. tauschii genes were syntenic with sorghum and rice genes, respectively. Synteny was reduced in the vicinity of the termini of modern Ae. tauschii chromosomes but not in the vicinity of the ancient termini embedded in the Ae. tauschii chromosomes, suggesting that the dependence of synteny erosion on gene location along the centromere–telomere axis either evolved recently in the Triticeae phylogenetic lineage or its evolution was recently accelerated. PMID:19717446

  12. [Detection of the introgression of genome elements of the Aegilops cylindrica host. into the Triticum aestivum L. genome by ISSR and SSR analysis].

    PubMed

    Galaev, A V; Babaiants, L T; Sivolap, Iu M

    2004-12-01

    To reveal sites of the donor genome in wheat crossed with Aegilops cylindrica, which acquired conferred resistance to fungal diseases, a comparative analysis of introgressive and parental forms was conducted. Two systems of PCR analysis, ISSR and SSR-PCR, were employed. Upon use of 7 ISSR primers in genotypes of 30 individual plants BC1 F9 belonging to lines 5/55-91 and 5/20-91, 19 ISSR loci were revealed and assigned to introgressive fragments of Aegilops cylindrica genome in Triticum aestivum. The 40 pairs of SSR primers allowed the detection of seven introgressive alleles; three of these alleles were located on common wheat chromosomes in the B genome, while four alleles, in the D genome. Based on data of microsatellite analysis, it was assumed that the telomeric region of the long arm of common wheat chromosome 6A also changed. ISSR and SSR methods were shown to be effective for detecting variability caused by introgression of foreign genetic material into the genome of common wheat. PMID:15648148

  13. Allocation of the S-genome chromosomes of Aegilops variabilis Eig. carrying powdery mildew resistance in triticale (× Triticosecale Wittmack).

    PubMed

    Kwiatek, M; Belter, J; Majka, M; Wiśniewska, H

    2016-03-01

    It has been hypothesized that the powdery mildew adult plant resistance (APR) controlled by the Pm13 gene in Aegilops longissima Schweinf. & Muschl. (S(l)S(l)) has been evolutionary transferred to Aegilops variabilis Eig. (UUSS). The molecular marker analysis and the visual evaluation of powdery mildew symptoms in Ae. variabilis and the Ae. variabilis × Secale cereale amphiploid forms (2n = 6x = 42, UUSSRR) showed the presence of product that corresponded to Pm13 marker and the lower infection level compared to susceptible model, respectively. This study also describes the transfer of Ae. variabilis Eig. (2n = 4x = 28, U(v)U(v)S(v)S(v)) chromosomes, carrying powdery mildew resistance, into triticale (× Triticosecale Wittm., 2n = 6x = 42, AABBRR) using Ae. variabilis × S. cereale amphiploid forms. The individual chromosomes of Ae. variabilis, triticale 'Lamberto' and hybrids were characterized by genomic and fluorescence in situ hybridization (GISH/FISH). The chromosome configurations of obtained hybrid forms were studied at first metaphase of meiosis of pollen mother cells (PMCs) using GISH. The statistical analysis showed that the way of S-genome chromosome pairing and transmission to subsequent hybrid generations was diploid-like and had no influence on chromosome pairing of triticale chromosomes. The cytogenetic study of hybrid forms were supported by the marker-assisted selection using Pm13 marker and visual evaluation of natural infection by Blumeria graminis, that allowed to select the addition or substitution lines of hybrids carrying chromosome 3S(v) which were tolerant to the powdery mildew infection. PMID:25868512

  14. Genetic structure of Aegilops cylindrica Host in its native range and in the United States of America.

    PubMed

    Gandhi, Harish T; Vales, M Isabel; Mallory-Smith, Carol; Riera-Lizarazu, Oscar

    2009-10-01

    Chloroplast and nuclear microsatellite markers were used to study genetic diversity and genetic structure of Aegilops cylindrica Host collected in its native range and in adventive sites in the USA. Our analysis suggests that Ae. cylindrica, an allotetraploid, arose from multiple hybridizations between Ae. markgrafii (Greuter) Hammer. and Ae. tauschii Coss. presumably along the Fertile Crescent, where the geographic distributions of its diploid progenitors overlap. However, the center of genetic diversity of this species now encompasses a larger area including northern Iraq, eastern Turkey, and Transcaucasia. Although the majority of accessions of Ae. cylindrica (87%) had D-type plastomes derived from Ae. tauschii, accessions with C-type plastomes (13%), derived from Ae. markgrafii, were also observed. This corroborates a previous study suggesting the dimaternal origin of Ae. cylindrica. Model-based and genetic distance-based clustering using both chloroplast and nuclear markers indicated that Ae. tauschii ssp. tauschii contributed one of its D-type plastomes and its D genome to Ae. cylindrica. Analysis of genetic structure using nuclear markers suggested that Ae. cylindrica accessions could be grouped into three subpopulations (arbitrarily named N-K1, N-K2, and N-K3). Members of the N-K1 subpopulation were the most numerous in its native range and members of the N-K2 subpopulation were the most common in the USA. Our analysis also indicated that Ae. cylindrica accessions in the USA were derived from a few founder genotypes. The frequency of Ae. cylindrica accessions with the C-type plastome in the USA (approximately 24%) was substantially higher than in its native range of distribution (approximately 3%) and all C-type Ae. cylindrica in the USA except one belonged to subpopulation N-K2. The high frequency of the C-type plastome in the USA may reflect a favorable nucleo-cytoplasmic combination. PMID:19618161

  15. 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...

  16. Genome-specific introgression between wheat and its wild relative Aegilops triuncialis.

    PubMed

    Parisod, C; Definod, C; Sarr, A; Arrigo, N; Felber, F

    2013-01-01

    Introgression of sequences from crop species in wild relatives is of fundamental and practical concern. Here, we address gene flow between cultivated wheat and its widespread polyploid relative, Aegilops triuncialis, using 12 EST-SSR markers mapped on wheat chromosomes. The presence of wheat diagnostic alleles in natural populations of the barbed goatgrass growing in proximity to cultivated fields highlights that substantial gene flow occurred when both species coexisted. Furthermore, loci from the A subgenome of wheat were significantly less introgressed than sequences from other subgenomes, indicating differential introgression into Ae. triuncialis. Gene flow between such species sharing nonhomeologous chromosomes addresses the evolutionary outcomes of hybridization and may be important for efficient gene containment. PMID:23205963

  17. Flow sorting of C-genome chromosomes from wild relatives of wheat Aegilops markgrafii, Ae. triuncialis and Ae. cylindrica, and their molecular organization

    PubMed Central

    Molnár, István; Vrána, Jan; Farkas, András; Kubaláková, Marie; Cseh, András; Molnár-Láng, Márta; Doležel, Jaroslav

    2015-01-01

    Background and Aims Aegilops markgrafii (CC) and its natural hybrids Ae. triuncialis (UtUtCtCt) and Ae. cylindrica (DcDcCcCc) represent a rich reservoir of useful genes for improvement of bread wheat (Triticum aestivum), but the limited information available on their genome structure and the shortage of molecular (cyto-) genetic tools hamper the utilization of the extant genetic diversity. This study provides the complete karyotypes in the three species obtained after fluorescent in situ hybridization (FISH) with repetitive DNA probes, and evaluates the potential of flow cytometric chromosome sorting. Methods The flow karyotypes obtained after the analysis of 4',6-diamidino-2-phenylindole (DAPI)-stained chromosomes were characterized and the chromosome content of the peaks on the flow karyotypes was determined by FISH. Twenty-nine conserved orthologous set (COS) markers covering all seven wheat homoeologous chromosome groups were used for PCR with DNA amplified from flow-sorted chromosomes and genomic DNA. Key Results FISH with repetitive DNA probes revealed that chromosomes 4C, 5C, 7Ct, T6UtS.6UtL-5CtL, 1Cc and 5Dc could be sorted with purities ranging from 66 to 91 %, while the remaining chromosomes could be sorted in groups of 2–5. This identified a partial wheat–C-genome homology for group 4 and 5 chromosomes. In addition, 1C chromosomes were homologous with group 1 of wheat; a small segment from group 2 indicated 1C–2C rearrangement. An extensively rearranged structure of chromosome 7C relative to wheat was also detected. Conclusions The possibility of purifying Aegilops chromosomes provides an attractive opportunity to investigate the structure and evolution of the Aegilops C genome and to develop molecular tools to facilitate the identification of alien chromatin and support alien introgression breeding in bread wheat. PMID:26043745

  18. Dynamic evolution of resistance gene analogs in the orthologous genomic regions of powdery mildew resistance gene MlIW170 in Triticum dicoccoides and Aegilops tauschii

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat is one of the most important staple grain crops in the world. Powdery mildew disease caused by Blumeria graminis f.sp. tritici can result in significant losses in both grain yield and quality in wheat. In this study, the wheat powdery mildew resistance gene MlIW170 locus located on the short ...

  19. Assessment of genomic and species relationships in Triticum and Aegilops by PAGE and by differential staining of seed albumins and globulins.

    PubMed

    Caldwell, K A; Kasarda, D D

    1978-11-01

    Endosperm protein components from common bread wheats (Triticum aestivum L.) and related species were extracted with aluminum lactate, pH 3.2, and examined by electrophoresis in the same buffer. Electrophoretic patterns of the albumins and globulins were compared to evaluate the possibility that a particular species might have contributed its genome to tetraploid or hexaploid wheat. Together with protein component mobilities, differential band staining with Coomassie Brilliant Blue R250 was employed to test the identity or non-identity of bands. Eight species and 63 accessions, representative of Triticum and Aegilops were tested. Considerable intraspecific variation was observed for patterns of diploid but not for tetraploid or hexaploid species. Patterns of some accessions of Triticum urartu agreed closely with major parts of the patterns of Triticum dicoccoides and T. aestivum. A fast-moving, green band was found in all accessions of T. urartu and of Triticum boeoticum, however, that was not found in those of T. dicoccoides or T. aestivum. This band was present in all accessions of Triticum araraticum and Triticum zhukovskyi. Patterns of Aegilops longissima, which has been suggested as the donor of the B genome, differed substantially from those of T. dicoccoides and T. aestivum. Finally, two marker proteins of intermediate mobility were also observed and may be used to discriminate between accessions of T. araraticum/T. zhukovskyi and those of T. dicoccoides/T. aestivum. PMID:24317663

  20. Visualization of A- and B-genome chromosomes in wheat (Triticum aestivum L.) x jointed goatgrass (Aegilops cylindrica Host) backcross progenies.

    PubMed

    Wang, Z N; Hang, A; Hansen, J; Burton, C; Mallory-Smith, C A; Zemetra, R S

    2000-12-01

    Wheat (Triticum aestivum) and jointed goatgrass (Aegilops cylindrica) can cross with each other, and their self-fertile backcross progenies frequently have extra chromosomes and chromosome segments, presumably retained from wheat, raising the possibility that a herbicide resistance gene might transfer from wheat to jointed goatgrass. Genomic in situ hybridization (GISH) was used to clarify the origin of these extra chromosomes. By using T. durum DNA (AABB genome) as a probe and jointed goatgrass DNA (CCDD genome) as blocking DNA, one, two, and three A- or B-genome chromosomes were identified in three BC2S2 individuals where 2n = 29, 30, and 31 chromosomes, respectively. A translocation between wheat and jointed goatgrass chromosomes was also detected in an individual with 30 chromosomes. In pollen mother cells with meiotic configuration of 14 II + 2 I, the two univalents were identified as being retained from the A or B genome of wheat. By using Ae. markgrafii DNA (CC genome) as a probe and wheat DNA (AABBDD genome) as blocking DNA. 14 C-genome chromosomes were visualized in all BC2S2 individuals. The GISH procedure provides a powerful tool to detect the A or B-genome chromatin in a jointed goatgrass background, making it possible to assess the risk of transfer of herbicide resistance genes located on the A or B genome of wheat to jointed goatgrass. PMID:11195336

  1. Characterization of high molecular weight glutenin subunits in Thinopyrum intermedium, Th. bessarabicum, Lophopyrum elongatum, Aegilops markgrafii, and their addition lines in wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    High molecular weight (HMW) glutenin subunits (GSs) play an important role in determining dough viscoelastic properties and end-use quality in cultivated wheat, and they are also excellent protein markers for genotype identification. The HMW-GSs in wheat species (Triticum ssp.) and Aegilops tauschii...

  2. [SSR mapping of stripe rust resistance gene from Ae. tauschii].

    PubMed

    Zhang, Hai-Quan; Jia, Ji-Zeng; Yang, Hong; Zhang, Bao-Shi

    2008-04-01

    A dominant wheat stripe rust resistance gene, temporarily designated as YrY201, was identified in an accession Y201 of Aegilops tauschii. By bulk segregation analysis, three microsatellite markers Xgwm273b, Xgwm37 and Wmc14 were found to be linked to YrY201 with genetic distance of 11.5, 5.8 and 10.9 cM , respectively. According to the locations of the linked markers, the resistance gene was located on chromosome 7DL. Based on the chromosomal location and the resistance pattern of the gene, we proposed that YrY201 was a novel stripe rust resistance gene, and could be selected by marker-assisted selection. PMID:18424421

  3. [Detection of the introgression of genome elements of Aegilops cylindrica Host. into Triticum aestivum L. genome with ISSR-analysis].

    PubMed

    Galaev, A V; Babaiants, L T; Sivolap, Iu M

    2003-01-01

    Comparative analysis of introgressive and parental forms of wheat was carried out to reveal the sites of donor genome with new loci of resistance to fungal diseases. By ISSR-method 124 ISSR-loci were detected in the genomes of 18 individual plants of introgressive line 5/20-91; 17 of them have been related to introgressive fragments of Ae. cylindrica genome in T. aestivum. It was shown that ISSR-method is effective for detection of the variability caused by introgression of alien genetic material to T. aestivum genome. PMID:12945176

  4. Genome-wide characterization of microsatellites in Triticeae species: abundance, distribution and evolution.

    PubMed

    Deng, Pingchuan; Wang, Meng; Feng, Kewei; Cui, Licao; Tong, Wei; Song, Weining; Nie, Xiaojun

    2016-01-01

    Microsatellites are an important constituent of plant genome and distributed across entire genome. In this study, genome-wide analysis of microsatellites in 8 Triticeae species and 9 model plants revealed that microsatellite characteristics were similar among the Triticeae species. Furthermore, genome-wide microsatellite markers were designed in wheat and then used to analyze the evolutionary relationship of wheat and other Triticeae species. Results displayed that Aegilops tauschii was found to be the closest species to Triticum aestivum, followed by Triticum urartu, Triticum turgidum and Aegilops speltoides, while Triticum monococcum, Aegilops sharonensis and Hordeum vulgare showed a relatively lower PCR amplification effectivity. Additionally, a significantly higher PCR amplification effectivity was found in chromosomes at the same subgenome than its homoeologous when these markers were subjected to search against different chromosomes in wheat. After a rigorous screening process, a total of 20,666 markers showed high amplification and polymorphic potential in wheat and its relatives, which were integrated with the public available wheat markers and then anchored to the genome of wheat (CS). This study not only provided the useful resource for SSR markers development in Triticeae species, but also shed light on the evolution of polyploid wheat from the perspective of microsatellites. PMID:27561724

  5. Genome-wide characterization of microsatellites in Triticeae species: abundance, distribution and evolution

    PubMed Central

    Deng, Pingchuan; Wang, Meng; Feng, Kewei; Cui, Licao; Tong, Wei; Song, Weining; Nie, Xiaojun

    2016-01-01

    Microsatellites are an important constituent of plant genome and distributed across entire genome. In this study, genome-wide analysis of microsatellites in 8 Triticeae species and 9 model plants revealed that microsatellite characteristics were similar among the Triticeae species. Furthermore, genome-wide microsatellite markers were designed in wheat and then used to analyze the evolutionary relationship of wheat and other Triticeae species. Results displayed that Aegilops tauschii was found to be the closest species to Triticum aestivum, followed by Triticum urartu, Triticum turgidum and Aegilops speltoides, while Triticum monococcum, Aegilops sharonensis and Hordeum vulgare showed a relatively lower PCR amplification effectivity. Additionally, a significantly higher PCR amplification effectivity was found in chromosomes at the same subgenome than its homoeologous when these markers were subjected to search against different chromosomes in wheat. After a rigorous screening process, a total of 20,666 markers showed high amplification and polymorphic potential in wheat and its relatives, which were integrated with the public available wheat markers and then anchored to the genome of wheat (CS). This study not only provided the useful resource for SSR markers development in Triticeae species, but also shed light on the evolution of polyploid wheat from the perspective of microsatellites. PMID:27561724

  6. 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

  7. 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

  8. [Genetics determination of wheat resistance to Puccinia graminis F. sp. tritici deriving from Aegilops cylindrica, Triticum erebuni and amphidiploid 4].

    PubMed

    Babaiants, O V; Babaiants, L T; Horash, A F; Vasil'ev, A A; Trackovetskaia, V A; Paliasn'iĭĭ, V A

    2012-01-01

    The lines of winter soft wheat developed in the Plant Breeding and Genetics Institute contain new effective introgressive Sr-genes. Line 85/06 possess SrAc1 gene, lines 47/06, 54/06, 82/06, 85/06, 87/06, 238/06, and 367/06 possess SrAc1 and SrAc2 derived from Aegilops cylindrica, line 352/06 - SrTe1 and SrTe2 from Triticum erebuni, line 12/86-04 - SrAd1 and SrAd2 from Amphidiploid 4 (Triticum dicoccoides x Triticum tauschii). PMID:22420215

  9. Cytogenetic analysis of Aegilops chromosomes, potentially usable in triticale (X Triticosecale Witt.) breeding.

    PubMed

    Kwiatek, M; Wiśniewska, H; Apolinarska, B

    2013-05-01

    Chromosome identification using fluorescence in situ hybridization (FISH) is widely used in cytogenetic research. It is a diagnostic tool helpful in chromosome identification. It can also be used to characterize alien introgressions, when exercised in a combination with genomic in situ hybridization (GISH). This work aims to find chromosome identification of Aegilops species and Aegilops × Secale amphiploids, which can be used in cereal breeding as a source of favourable agronomic traits. Four diploid and two tetraploid Aegilops species and three Aegilops × Secale hybrids were analysed using FISH with pSc119.2, pAs1, 5S rDNA and 25S rDNA clones to differentiate the U-, M-, S(sh)- and D-subgenome chromosomes of Aegilops genus. Additionally, GISH for chromosome categorization was carried out. Differences in the hybridization patterns allowed to identify all U-, M-, S(sh)- and D-subgenome chromosomes. Some differences in localization of the rDNA, pSc119.2 and pAs1 sequences between analogue subgenomes in diploid and tetraploid species and Aegilops × Secale hybrids were detected. The hybridization pattern of the M and S genome was more variable than that of the U and D genome. An importance of the cytogenetic markers in plant breeding and their possible role in chromosome structure, function and evolution is discussed. PMID:23378244

  10. Mapping Septoria Leaf Blotch and Soil-borne Mosaic Virus Resistance Genes Derived from Aegilops tauschii

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Septoria leaf blotch (STB) is a fungal disease of wheat caused by Septoria tritici and is routinely a problem in temperate wheat growing regions. Soil-borne Wheat Mosaic Virus (SBWMV) is a destructive pathogen of wheat that can cause entire crop failure in localized fields. A linkage analysis of a...

  11. Fine genetic mapping of greenbug aphid resistance gene Gb3 in Aegilops tauschii

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The greenbug is a serious aphid pest of wheat and sorghum in the southern High Plains of the US. The greenbug resistant gene Gb3 originated from the goatgrass has shown consistent and durable resistance against prevailing greenbug biotypes in wheat fields for moer than 30 years. Our goal is to clone...

  12. Fine Mapping of Hessian Fly Resistance Gene H26 in an Aegilops tauschii Population

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hessian fly [Mayetiola destructor (Say)] is one of the most important insect pests in wheat (Triticum L.) around the world. Among the 32 genes known to confer wheat resistance to Hessian fly, the H26 is important because it is effective against several highly virulent Hessian fly populations. The H...

  13. Adult plant resistance to Puccinia triticina in a geographically diverse collection of Aegilops tauschii

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Despite extensive genetics and breeding research, effective control of leaf rust caused by Puccinia triticina Eriks., an important foliar disease of wheat, has not been achieved. This is mainly due to the widespread use of race-specific seedling resistance genes, which are rapidly overcome by new vi...

  14. Genetic Analysis of Resistance to Soil-borne Wheat Mosiac Virus Derived from Aegilops tauschii

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil-borne Wheat Mosaic Virus (SBWMV), vectored by the soil inhabiting fungus Polymyxa graminis, causes damage to wheat (Triticum aestivum) yields in most of the wheat growing regions of the world. In localized fields, the entire crop may be lost to the virus. Although many winter wheat cultivars ...

  15. PGSB PlantsDB: updates to the database framework for comparative plant genome research.

    PubMed

    Spannagl, Manuel; Nussbaumer, Thomas; Bader, Kai C; Martis, Mihaela M; Seidel, Michael; Kugler, Karl G; Gundlach, Heidrun; Mayer, Klaus F X

    2016-01-01

    PGSB (Plant Genome and Systems Biology: formerly MIPS) PlantsDB (http://pgsb.helmholtz-muenchen.de/plant/index.jsp) is a database framework for the comparative analysis and visualization of plant genome data. The resource has been updated with new data sets and types as well as specialized tools and interfaces to address user demands for intuitive access to complex plant genome data. In its latest incarnation, we have re-worked both the layout and navigation structure and implemented new keyword search options and a new BLAST sequence search functionality. Actively involved in corresponding sequencing consortia, PlantsDB has dedicated special efforts to the integration and visualization of complex triticeae genome data, especially for barley, wheat and rye. We enhanced CrowsNest, a tool to visualize syntenic relationships between genomes, with data from the wheat sub-genome progenitor Aegilops tauschii and added functionality to the PGSB RNASeqExpressionBrowser. GenomeZipper results were integrated for the genomes of barley, rye, wheat and perennial ryegrass and interactive access is granted through PlantsDB interfaces. Data exchange and cross-linking between PlantsDB and other plant genome databases is stimulated by the transPLANT project (http://transplantdb.eu/). PMID:26527721

  16. PGSB PlantsDB: updates to the database framework for comparative plant genome research

    PubMed Central

    Spannagl, Manuel; Nussbaumer, Thomas; Bader, Kai C.; Martis, Mihaela M.; Seidel, Michael; Kugler, Karl G.; Gundlach, Heidrun; Mayer, Klaus F.X.

    2016-01-01

    PGSB (Plant Genome and Systems Biology: formerly MIPS) PlantsDB (http://pgsb.helmholtz-muenchen.de/plant/index.jsp) is a database framework for the comparative analysis and visualization of plant genome data. The resource has been updated with new data sets and types as well as specialized tools and interfaces to address user demands for intuitive access to complex plant genome data. In its latest incarnation, we have re-worked both the layout and navigation structure and implemented new keyword search options and a new BLAST sequence search functionality. Actively involved in corresponding sequencing consortia, PlantsDB has dedicated special efforts to the integration and visualization of complex triticeae genome data, especially for barley, wheat and rye. We enhanced CrowsNest, a tool to visualize syntenic relationships between genomes, with data from the wheat sub-genome progenitor Aegilops tauschii and added functionality to the PGSB RNASeqExpressionBrowser. GenomeZipper results were integrated for the genomes of barley, rye, wheat and perennial ryegrass and interactive access is granted through PlantsDB interfaces. Data exchange and cross-linking between PlantsDB and other plant genome databases is stimulated by the transPLANT project (http://transplantdb.eu/). PMID:26527721

  17. Sequencing of 15 622 gene-bearing BACs clarifies the gene-dense regions of the barley genome.

    PubMed

    Muñoz-Amatriaín, María; Lonardi, Stefano; Luo, MingCheng; Madishetty, Kavitha; Svensson, Jan T; Moscou, Matthew J; Wanamaker, Steve; Jiang, Tao; Kleinhofs, Andris; Muehlbauer, Gary J; Wise, Roger P; Stein, Nils; Ma, Yaqin; Rodriguez, Edmundo; Kudrna, Dave; Bhat, Prasanna R; Chao, Shiaoman; Condamine, Pascal; Heinen, Shane; Resnik, Josh; Wing, Rod; Witt, Heather N; Alpert, Matthew; Beccuti, Marco; Bozdag, Serdar; Cordero, Francesca; Mirebrahim, Hamid; Ounit, Rachid; Wu, Yonghui; You, Frank; Zheng, Jie; Simková, Hana; Dolezel, Jaroslav; Grimwood, Jane; Schmutz, Jeremy; Duma, Denisa; Altschmied, Lothar; Blake, Tom; Bregitzer, Phil; Cooper, Laurel; Dilbirligi, Muharrem; Falk, Anders; Feiz, Leila; Graner, Andreas; Gustafson, Perry; Hayes, Patrick M; Lemaux, Peggy; Mammadov, Jafar; Close, Timothy J

    2015-10-01

    Barley (Hordeum vulgare L.) possesses a large and highly repetitive genome of 5.1 Gb that has hindered the development of a complete sequence. In 2012, the International Barley Sequencing Consortium released a resource integrating whole-genome shotgun sequences with a physical and genetic framework. However, because only 6278 bacterial artificial chromosome (BACs) in the physical map were sequenced, fine structure was limited. To gain access to the gene-containing portion of the barley genome at high resolution, we identified and sequenced 15 622 BACs representing the minimal tiling path of 72 052 physical-mapped gene-bearing BACs. This generated ~1.7 Gb of genomic sequence containing an estimated 2/3 of all Morex barley genes. Exploration of these sequenced BACs revealed that although distal ends of chromosomes contain most of the gene-enriched BACs and are characterized by high recombination rates, there are also gene-dense regions with suppressed recombination. We made use of published map-anchored sequence data from Aegilops tauschii to develop a synteny viewer between barley and the ancestor of the wheat D-genome. Except for some notable inversions, there is a high level of collinearity between the two species. The software HarvEST:Barley provides facile access to BAC sequences and their annotations, along with the barley-Ae. tauschii synteny viewer. These BAC sequences constitute a resource to improve the efficiency of marker development, map-based cloning, and comparative genomics in barley and related crops. Additional knowledge about regions of the barley genome that are gene-dense but low recombination is particularly relevant. PMID:26252423

  18. Allelic variations of α-gliadin genes from species of Aegilops section Sitopsis and insights into evolution of α-gliadin multigene family among Triticum and Aegilops.

    PubMed

    Huang, Zhuo; Long, Hai; Wei, Yu-Ming; Yan, Ze-Hong; Zheng, You-Liang

    2016-04-01

    The α-gliadins account for 15-30 % of the total storage protein in wheat endosperm and play important roles in the dough extensibility and nutritional quality. On the other side, they act as a main source of toxic peptides triggering celiac disease. In this study, 37 α-gliadins were isolated from three species of Aegilops section Sitopsis. Sequence similarity and phylogenetic analyses revealed novel allelic variation at Gli-2 loci of species of Sitopsis and regular organization of motifs in their repetitive domain. Based on the comprehensive analyses of a large number of known sequences of bread wheat and its diploid genome progenitors, the distributions of four T cell epitopes and length variations of two polyglutamine domains are analyzed. Additionally, according to the organization of repeat motifs, we classified the α-gliadins of Triticum and Aegilops into eight types. Their most recent common ancestor and putative divergence patterns were further considered. This study provides new insights into the allelic variations of α-gliadins in Aegilops section Sitopsis, as well as evolution of α-gliadin multigene family among Triticum and Aegilops species. PMID:26940567

  19. Analysis of ATP6 sequence diversity in the Triticum-Aegilops group of species reveals the crucial role of rearrangement in mitochondrial genome evolution

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mutation and chromosomal rearrangements are the two main forces of increasing genetic diversity for natural selection to act upon, and ultimately drive the evolutionary process. Although genome evolution is a function of both forces, simultaneously, the ratio of each can be varied among different ge...

  20. Comparison of genome-wide gene expression patterns in the seedlings of nascent allohexaploid wheats produced by two combinations of hybrids.

    PubMed

    Jung, Yeonju; Kawaura, Kanako; Kishii, Masahiro; Sakuma, Shun; Ogihara, Yasunari

    2015-01-01

    Allopolyploidization in plants is an important event that enhances heterosis and environmental adaptation. Common wheat, Triticum aestivum (AABBDD), which is an allohexaploid that evolved from an allopolyploidization event between T. turgidum (AABB) and Aegilops tauschii (DD), shows more growth vigor and wider adaptation than tetraploid wheats. To better understand the molecular basis for the heterosis of hexaploid wheat, we systematically analyzed the genome-wide gene expression patterns of two combinations of newly hybridized triploids (ABD), their chromosome-doubled hexaploids (AABBDD), stable synthetic hexaploids (AABBDD) and natural hexaploids, in addition to their parents, T. turgidum (AABB) and Ae. tauschii (DD), using a microarray to reconstruct the events of allopolyploidization and genome stabilization. Overall comparisons of gene expression profiles showed that the newly generated hexaploids exhibited gene expression patterns similar to those of their maternal tetraploids, irrespective of hybrid combination. With successive generations, the gene expression profiles of nascent hexaploids became less similar to the maternal profiles, and belonged to a separate cluster from the natural hexaploids. Triploids revealed characteristic expression patterns, suggesting endosperm effects. In the newly hybridized triploids (ABD) of two independent synthetic lines, approximately one-fifth of expressed genes displayed non-additive expression; the number of these genes decreased with polyploidization and genome stabilization. Approximately 20% of the non-additively expressed genes were transmitted across generations throughout allopolyploidization and successive self-pollinations, and 43 genes overlapped between the two combinations, indicating that shared gene expression patterns can be seen during allohexaploidization. Furthermore, four of these 43 genes were involved in starch and sucrose metabolism, suggesting that these metabolic events play key roles in the

  1. Identification of a major QTL controlling the content of B-type starch granules in Aegilops

    PubMed Central

    Howard, Thomas; Rejab, Nur Ardiyana; Griffiths, Simon; Leigh, Fiona; Leverington-Waite, Michelle; Simmonds, James; Uauy, Cristobal; Trafford, Kay

    2011-01-01

    Starch within the endosperm of most species of the Triticeae has a unique bimodal granule morphology comprising large lenticular A-type granules and smaller near-spherical B-type granules. However, a few wild wheat species (Aegilops) are known to lack B-granules. Ae. peregrina and a synthetic tetraploid Aegilops with the same genome composition (SU) were found to differ in B-granule number. The synthetic tetraploid had normal A- and B-type starch granules whilst Ae. peregrina had only A-granules because the B-granules failed to initiate. A population segregating for B-granule number was generated by crossing these two accessions and was used to study the genetic basis of B-granule initiation. A combination of Bulked Segregant Analysis and QTL mapping identified a major QTL located on the short arm of chromosome 4S that accounted for 44.4% of the phenotypic variation. The lack of B-granules in polyploid Aegilops with diverse genomes suggests that the B-granule locus has been lost several times independently during the evolution of the Triticeae. It is proposed that the B-granule locus is susceptible to silencing during polyploidization and a model is presented to explain the observed data based on the assumption that the initiation of B-granules is controlled by a single major locus per haploid genome. PMID:21227932

  2. 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

  3. 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

  4. Evaluation and characterization of high-molecular weight 1D glutenin subunits from Aegilops tauschii in synthetic hexaploid wheats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The high-molecular weight (HMW) glutenin subunits of bread wheat (Triticum aestivum L.) are major determinants of end-use quality. The objective of this study was to determine the 1Dx and 1Dy HMW subunits present in 44 synthetic hexaploid wheats (SHW) derived by crossing Langdon durum (T. turgidum ...

  5. Transmission of the Aegilops ovata chromosomes carrying gametocidal factors in hexaploid triticale (×Triticosecale Wittm.) hybrids.

    PubMed

    Kwiatek, M; Majka, M; Ślusarkiewicz-Jarzina, A; Ponitka, A; Pudelska, H; Belter, J; Wiśniewska, H

    2016-08-01

    The main aim of this work was to induce the chromosome rearrangements between Aegilops ovata (UUMM) and hexaploid triticale (AABBRR) by expression of the gametocidal factor located on the chromosome 4M. The Aegilops ovata × Secale cereale (UUMMRR) amphiploids and triticale 'Moreno' were used to produce hybrids by reciprocal crosses. Chromosome dynamics was observed in subsequent generations of hybrids during mitotic metaphase of root meristems and first metaphase of meiosis of pollen mother cells. Chromosomes were identified by genomic in situ hybridisation (GISH) and fluorescence in situ hybridisation (FISH) using pTa71, pTa791, pSc119.2 and pAs1 DNA probes. It has been shown that the origin of the genetic background had an influence on Aegilops chromosome transmission. Moreover, it has been reported that the preferential transmission of chromosome 4M appeared during both androgenesis and gynogenesis. It is also hypothesised that the expression of the triticale Gc gene suppressor had an influence on the semi-fertility of hybrids but did not inhibit the chromosome rearrangements. This paper also describes the double haploid production, which enabled to obtain plants with two identical copies of triticale chromosomes with translocations of Aegilops chromatin segments. PMID:26825077

  6. 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

  7. 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

  8. 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...

  9. 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

  10. [Molecular-genetic analysis of wheat (T. aestivum L.) genome with introgression of Ae. cylindrica Host genetic elements].

    PubMed

    Galaev, A V; Sivolap, Iu M

    2005-01-01

    Wheat-aegilops hybrid plants Triticum aestivum L. (2n = 42) x Aegilops cylindrica Host (2n = 28) were investigated with using microsatellite markers. In two BC1F9 lines some genome modifications connected with losing DNA fragments of initial variety or appearing of Aegilops genome elements were detected. In some investigated hybrids new amplicons lacking in parental plants were found. Substitution of wheat chromosomes for aegilops chromosomes was not revealed. Analysis of microsatellite loci in BC2F5 plants showed stable introgression of aegilops genetic elements into wheat; elimination of some transferred aegilops DNA fragments in the course of backcrossing; decreasing size of introgressive elements after backcrossing. Introgressive lines were classified according to genome changes. PMID:16250247

  11. 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

  12. Molecular Cytogenetic Mapping of Satellite DNA Sequences in Aegilops geniculata and Wheat.

    PubMed

    Koo, Dal-Hoe; Tiwari, Vijay K; Hřibová, Eva; Doležel, Jaroslav; Friebe, Bernd; Gill, Bikram S

    2016-01-01

    Fluorescence in situ hybridization (FISH) provides an efficient system for cytogenetic analysis of wild relatives of wheat for individual chromosome identification, elucidation of homoeologous relationships, and for monitoring alien gene transfers into wheat. This study is aimed at developing cytogenetic markers for chromosome identification of wheat and Aegilops geniculata (2n = 4x = 28, UgUgMgMg) using satellite DNAs obtained from flow-sorted chromosome 5Mg. FISH was performed to localize the satellite DNAs on chromosomes of wheat and selected Aegilops species. The FISH signals for satellite DNAs on chromosome 5Mg were generally associated with constitutive heterochromatin regions corresponding to C-band-positive chromatin including telomeric, pericentromeric, centromeric, and interstitial regions of all the 14 chromosome pairs of Ae. geniculata. Most satellite DNAs also generated FISH signals on wheat chromosomes and provided diagnostic chromosome arm-specific cytogenetic markers that significantly improved chromosome identification in wheat. The newly identified satellite DNA CL36 produced localized Mg genome chromosome-specific FISH signals in Ae. geniculata and in the M genome of the putative diploid donor species Ae. comosa subsp. subventricosa but not in Ae. comosa subsp. comosa, suggesting that the Mg genome of Ae. geniculata was probably derived from subsp. subventricosa. PMID:27403741

  13. Sequencing of chloroplast genomes from wheat, barley, rye and their relatives provides a detailed insight into the evolution of the Triticeae tribe.

    PubMed

    Middleton, Christopher P; Senerchia, Natacha; Stein, Nils; Akhunov, Eduard D; Keller, Beat; Wicker, Thomas; Kilian, Benjamin

    2014-01-01

    Using Roche/454 technology, we sequenced the chloroplast genomes of 12 Triticeae species, including bread wheat, barley and rye, as well as the diploid progenitors and relatives of bread wheat Triticum urartu, Aegilops speltoides and Ae. tauschii. Two wild tetraploid taxa, Ae. cylindrica and Ae. geniculata, were also included. Additionally, we incorporated wild Einkorn wheat Triticum boeoticum and its domesticated form T. monococcum and two Hordeum spontaneum (wild barley) genotypes. Chloroplast genomes were used for overall sequence comparison, phylogenetic analysis and dating of divergence times. We estimate that barley diverged from rye and wheat approximately 8-9 million years ago (MYA). The genome donors of hexaploid wheat diverged between 2.1-2.9 MYA, while rye diverged from Triticum aestivum approximately 3-4 MYA, more recently than previously estimated. Interestingly, the A genome taxa T. boeoticum and T. urartu were estimated to have diverged approximately 570,000 years ago. As these two have a reproductive barrier, the divergence time estimate also provides an upper limit for the time required for the formation of a species boundary between the two. Furthermore, we conclusively show that the chloroplast genome of hexaploid wheat was contributed by the B genome donor and that this unknown species diverged from Ae. speltoides about 980,000 years ago. Additionally, sequence alignments identified a translocation of a chloroplast segment to the nuclear genome which is specific to the rye/wheat lineage. We propose the presented phylogeny and divergence time estimates as a reference framework for future studies on Triticeae. PMID:24614886

  14. Study of the repeatability of histone genes in the ploidy series of wheat and Aegilops

    SciTech Connect

    Vakhitov, V.A.; Kulikov, A.M.

    1986-10-01

    The hDNA content and number of histone genes in the genomes of different wheat and Aegilops species have been determined by molecular hybridization of DNA with /sup 125/I-histone DNA of Drosophila (L-repeat) on nitrocellulose filters. It has been demonstrated that the proportion of hDNA in the total DNA of diploid and polyploid wheat species is (1.3-7.7) x 10/sup -3/% (57-850 genes), and in the ploidy series of Aegilops species (2.0-8.0) x 10/sup -3/% (89-780 genes). The repeatability of the histone genes generally increases at each ploidy level in the species with higher DNA content. At the same time, it has been demonstrated that the DNA content is not the only factor determining repeatability of the histone genes, as some diploid and allopolyploid species have similar number of these genes. It has been concluded that genetic mechanisms are involved in the regulation of the number of histone genes.

  15. Screening The Aegilops-Triticum Group For Boron Tolerance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Boron deficient and toxic soils pose a critical problem in wheat production on a world scale. Therefore, 79 accessions from 12 diverse wild wheat (Aegilops speltoides, Ae. longissima, Ae. sharonensis, Ae. bicornis, Ae. searsii, Ae. kotschyi, Ae. peregrina ssp. cylindrostachys, Ae. peregrina ssp. eu...

  16. [Hybrids of Aegilops cylindrica Host with Triticum durum Desf. and T. aestivum L].

    PubMed

    Avsenin, V I; Motsnyĭ, A I; Rybalka, A I; Faĭt, V I

    2003-01-01

    The hybrids of durum and bread wheat with Ae. cylindrica have been obtained without using an embryo rescue technique. The hybrid output (of pollinated flower number) in the field conditions scored 1.0, 15.3 and 10.0% in the crosses T. durum x Ae. cylindrica, Ae. cylindrica x T. durum and T. aestivum x Ae. cylindrica, respectively. A high level of meiotic chromosome pairing between homologous D genomes of bread wheat and Aegilops has been revealed (c = 80.0-83.7%). The possibility of homoeological pairing between wheat and Ae. cylindrica chromosomes has been shown. Herewith, the correlation between the levels of homological and homoeological pairing is absent. The possibilities of genetic material interchange, including between the tetraploid species, as well as the using of Ae. cylindrica cytoplasm for durum wheat breeding are discussed. PMID:12741056

  17. 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

  18. Development of genome-specific primers for homoeologous genes in allopolyploid species: the waxy and starch synthase II genes in allohexaploid wheat (Triticum aestivum L.) as examples

    PubMed Central

    2010-01-01

    Background In allopolypoid crops, homoeologous genes in different genomes exhibit a very high sequence similarity, especially in the coding regions of genes. This makes it difficult to design genome-specific primers to amplify individual genes from different genomes. Development of genome-specific primers for agronomically important genes in allopolypoid crops is very important and useful not only for the study of sequence diversity and association mapping of genes in natural populations, but also for the development of gene-based functional markers for marker-assisted breeding. Here we report on a useful approach for the development of genome-specific primers in allohexaploid wheat. Findings In the present study, three genome-specific primer sets for the waxy (Wx) genes and four genome-specific primer sets for the starch synthase II (SSII) genes were developed mainly from single nucleotide polymorphisms (SNPs) and/or insertions or deletions (Indels) in introns and intron-exon junctions. The size of a single PCR product ranged from 750 bp to 1657 bp. The total length of amplified PCR products by these genome-specific primer sets accounted for 72.6%-87.0% of the Wx genes and 59.5%-61.6% of the SSII genes. Five genome-specific primer sets for the Wx genes (one for Wx-7A, three for Wx-4A and one for Wx-7D) could distinguish the wild type wheat and partial waxy wheat lines. These genome-specific primer sets for the Wx and SSII genes produced amplifications in hexaploid wheat, cultivated durum wheat, and Aegilops tauschii accessions, but failed to generate amplification in the majority of wild diploid and tetraploid accessions. Conclusions For the first time, we report on the development of genome-specific primers from three homoeologous Wx and SSII genes covering the majority of the genes in allohexaploid wheat. These genome-specific primers are being used for the study of sequence diversity and association mapping of the three homoeologous Wx and SSII genes in natural

  19. Grain protein variability among species of Triticum and Aegilops: quantitative SDS-PAGE studies.

    PubMed

    Cole, E W; Fullington, J G; Kasarda, D D

    1981-01-01

    Total proteins were extracted from degermed seeds of various species of Triticum and Aegilops with solutions containing sodium dodecyl sulfate (SDS) and mercaptoethanol. The reduced, dissociated proteins were fractionated according to molecular weight (MW) by high-resolution polyacrylamide gel electrophoresis in buffers containing SDS (SDS-PAGE). Stained SDS-PAGE patterns were measured by densitometric scanning over a suitable range of optical density. The data were normalized to equivalent total areas for each of the densitometric scans by means of a computer program that also permitted the construction of patterns of hypothetical amphiploids by averaging patterns of two or three diploid species. The grain proteins of most species examined had distinctive qualitative and quantitative aspects that were characteristic of the species even though nearly every accession or cultivar of a species exhibited at least minor differences in pattern from other accessions or cultivars. The main protein components (probably prolamins) of Triticum monococcum ssp. monococcum, T. monococcum ssp. boeoticum, T. urartu, and Aegilops squarrosa had MW's in the range 29-36 X 10(3) whereas the most important components of Ae. speltoides, Ae. longissima, and Ae. searsii had MW's in the range 37-55 × 10(3). Changes in the quantitative expression of particular genes, especially those coding for storage protein components, may have been associated with speciation. The strong predominance of proteins with MW's in the range 29-36 × 10(3) in some accessions of AB genome tetraploids, such as T. turgidum ssp. dicoccoides, may indicate contributions to the B genome of these tetraploids by T. monococcum ssp. boeoticum, T. urartu, or Ae. squarrosa. PMID:24276584

  20. Synthetic hexaploids derived from under-exploited tetraploids as a new resource for disease resistance in wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Synthetic hexaploid wheat (SHW) (2n = 6x = 42, genome AABBDD), which is developed from the hybridization between tetraploid wheat (Triticum turgidum L., 2n = 4x = 28, genome AABB) and Aegilops tauschii Coss. (2n = 2x = 14, genome DD), is a useful bridging germplasm for the introgression of desirable...

  1. 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...

  2. Chromosomal location of Pm35, a novel Aegilops tauschii derived powdery mildew resistance gene introgressed into common wheat (Triticum aestivum L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A single gene controlling powdery mildew resistance was identified in the North Carolina germplasm line NC96BGTD3 (NCD3) using genetic analysis of F2 derived lines from a NCD3 X Saluda cross. Microsatellite markers linked to this Pm gene were identified and their most likely order was Xcfd7, 10.3cM,...

  3. Identification and mapping of Sr46 from Aegilops tauschii accession CIae 25 conferring resistance to race TTKSK (Ug99) of wheat stem rust pathogen

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The race TTKSK (Ug99) of Puccinia graminis f. sp. tritici, the casual pathogen for wheat stem rust, is currently a major threat to global wheat production. To confine this threat, researchers across the world have been devoted to identifying TTKSK-resistant genes. Here, we report the identificatio...

  4. Rapid evolutionary dynamics in a 2.8-Mb chromosomal region containing multiple prolamin and resistance gene families in Aegilops tauschii

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The prolamin (seed storage proteins high in glutamine and proline) and resistance gene families are important in domesticated bread wheat (Triticum aestivum) food uses and in defense against pathogen attacks, respectively. To better understand the evolution of these multi-gene families, the DNA se...

  5. Lr41, Lr39, and a leaf rust resistance gene from Aegilops cylindrica may be allelic and are located on wheat chromosome 2DS.

    PubMed

    Singh, Sukhwinder; Franks, C D; Huang, L; Brown-Guedira, G L; Marshall, D S; Gill, B S; Fritz, A

    2004-02-01

    The leaf rust resistance gene Lr41 in wheat germplasm KS90WGRC10 and a resistance gene in wheat breeding line WX93D246-R-1 were transferred to Triticum aestivum from Aegilops tauschii and Ae. cylindrica, respectively. The leaf rust resistance gene in WX93D246-R-1 was located on wheat chromosome 2D by monosomic analysis. Molecular marker analysis of F(2) plants from non-critical crosses determined that this gene is 11.2 cM distal to marker Xgwm210 on the short arm of 2D. No susceptible plants were detected in a population of 300 F(2) plants from a cross between WX93D246-R-1 and TA 4186 ( Lr39), suggesting that the gene in WX93D246-R-1 is the same as, or closely linked to, Lr39. In addition, no susceptible plants were detected in a population of 180 F(2) plants from the cross between KS90WGRC10 and WX93D246-R-1. The resistance gene in KS90WGRC10, Lr41, was previously reported to be located on wheat chromosome 1D. In this study, no genetic association was found between Lr41 and 51 markers located on chromosome 1D. A population of 110 F(3 )lines from a cross between KS90WGRC10 and TAM 107 was evaluated with polymorphic SSR markers from chromosome 2D and marker Xgdm35 was found to be 1.9 cM proximal to Lr41. When evaluated with diverse isolates of Puccinia triticina, similar reactions were observed on WX93D246-R-1, KS90WGRC10, and TA 4186. The results of mapping, allelism, and race specificity test indicate that these germplasms likely have the same gene for resistance to leaf rust. PMID:14534751

  6. 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...

  7. 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...

  8. 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...

  9. 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 ...

  10. 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 ...

  11. 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...

  12. Quantum speciation in Aegilops: Molecular cytogenetic evidence from rDNA cluster variability in natural populations

    PubMed Central

    Raskina, Olga; Belyayev, Alexander; Nevo, Eviatar

    2004-01-01

    Data are presented on quantum speciation in the Sitopsis section of the genus Aegilops (Poaceae, Monocotyledones). Two small, peripheral, isolated, wild populations of annual cross-pollinated Ae. speltoides and annual self-pollinated Ae. sharonensis are located 30 m apart on different soil types. Despite the close proximity of the two species and their close relatedness, no mixed groups are known. Comparative molecular cytogenetic analysis based on the intrapopulation variability of rRNA-encoding DNA (rDNA) chromosomal patterns of individual Ae. speltoides geno-types revealed an ongoing dynamic process of permanent chromosomal rearrangements. Chromosomal mutations can arise de novo and can be eliminated. Analysis of the progeny of the investigated genotypes testifies that inheritance of de novo rDNA sites happens frequently. Heterologous recombination and/or transposable elements-mediated rDNA transfer seem to be the mechanisms for observed chromosomal repatterning. Consequently, several modified genomic forms, intermediate between Ae. speltoides and Ae. sharonensis, permanently arise in the studied wild population of Ae. speltoides, which make it possible to recognize Ae. sharonensis as a derivative species of Ae. speltoides, as well as to propose rapidness and canalization of quantum speciation in Sitopsis species. PMID:15466712

  13. 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

  14. Chromosome evolution in marginal populations of Aegilops speltoides: causes and consequences

    PubMed Central

    Belyayev, Alexander; Raskina, Olga

    2013-01-01

    Background Genome restructuring is an ongoing process in natural plant populations. The influence of environmental changes on the genome is crucial, especially during periods of extreme climatic fluctuations. Interactions between the environment and the organism manifest to the greatest extent at the limits of the species' ecological niche. Thus, marginal populations are expected to exhibit lower genetic diversity and higher genetic differentiation than central populations, and some models assume that marginal populations play an important role in the maintenance and generation of biological diversity. Scope In this review, long-term data on the cytogenetic characteristics of diploid Aegilops speltoides Tauch populations are summarized and discussed. This species is distributed in and around the Fertile Crescent and is proposed to be the wild progenitor of a number of diploid and polyploid wheat species. In marginal populations of Ae. speltoides, numerical chromosomal aberrations, spontaneous aneuploidy, B-chromosomes, rDNA cluster repatterning and reduction in the species-specific and tribe-specific tandem repeats have been detected. Significant changes were observed and occurred in parallel with changes in plant morphology and physiology. Conclusions Considerable genomic variation at the chromosomal level was found in the marginal populations of Ae. speltoides. It is likely that a specific combination of gene mutations and chromosomal repatterning has produced the evolutionary trend in each specific case, i.e. for a particular species or group of related species in a given period of time and in a certain habitat. The appearance of a new chromosomal pattern is considered an important factor in promoting the emergence of interbreeding barriers. PMID:23393097

  15. 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...

  16. A comparative analysis of chromosome pairing at metaphase I in interspecific hybrids between durum wheat (Triticum turgidum L.) and the most widespread Aegilops species.

    PubMed

    Cifuentes, M; Garcia-Agüero, V; Benavente, E

    2010-07-01

    Homoeologous metaphase I (MI) associations in hybrids between durum wheat and its wild allotetraploid relatives Aegilops neglecta, Ae. triuncialis and Ae. ventricosa have been characterized by a genomic in situ hybridization procedure that allows simultaneous discrimination of A, B and wild species genomes. Earlier results in equivalent hybrids with the wild species Ae. cylindrica and Ae. geniculata have also been considered to comparatively assay the MI pairing pattern of the durum wheat x Aegilops interspecific combinations more likely to occur in nature. The general picture can be drawn as follows. A and B wheat genomes pair with each other less than the 2 wild constituent genomes do in any of the hybrid combinations examined. Interspecific wheat-wild associations account for 60-70% of total MI pairing in all hybrids, except in that derived from Ae. triuncialis, but the A genome is always the wheat partner most frequently involved in MI pairing with the wild homoeologues. Hybrids with Ae. cylindrica, Ae. geniculata and Ae. ventricosa showed similar reduced levels of MI association and virtually identical MI pairing patterns. However, certain recurrent differences were found when the pattern of homoeologous pairing of hybrids from either Ae. triuncialis or Ae. neglecta was contrasted to that observed in the other durum wheat hybrid combinations. In the former case, a remarkable preferential pairing between the wild species constituent genomes U(t) and C(t) seems to be the reason, whereas a general promotion of homoeologous pairing, qualitatively similar to that observed under the effect of the ph1c mutation, appears to occur in the hybrid with Ae. neglecta. It is further discussed whether the results reported here can be extrapolated to the corresponding bread wheat hybrid combinations. PMID:20551603

  17. Gene flow between wheat and wild relatives: empirical evidence from Aegilops geniculata, Ae. neglecta and Ae. triuncialis

    PubMed Central

    Arrigo, Nils; Guadagnuolo, Roberto; Lappe, Sylvain; Pasche, Sophie; Parisod, Christian; Felber, François

    2011-01-01

    Gene flow between domesticated species and their wild relatives is receiving growing attention. This study addressed introgression between wheat and natural populations of its wild relatives (Aegilops species). The sampling included 472 individuals, collected from 32 Mediterranean populations of three widespread Aegilops species (Aegilops geniculata, Ae. neglecta and Ae. triuncialis) and compared wheat field borders to areas isolated from agriculture. Individuals were characterized with amplified fragment length polymorphism fingerprinting, analysed through two computational approaches (i.e. Bayesian estimations of admixture and fuzzy clustering), and sequences marking wheat-specific insertions of transposable elements. With this combined approach, we detected substantial gene flow between wheat and Aegilops species. Specifically, Ae. neglecta and Ae. triuncialis showed significantly more admixed individuals close to wheat fields than in locations isolated from agriculture. In contrast, little evidence of gene flow was found in Ae. geniculata. Our results indicated that reproductive barriers have been regularly bypassed during the long history of sympatry between wheat and Aegilops. PMID:25568015

  18. 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

  19. Transfer of useful variability of high grain iron and zinc from Aegilops kotschyi into wheat through seed irradiation approach.

    PubMed

    Verma, Shailender Kumar; Kumar, Satish; Sheikh, Imran; Malik, Sachin; Mathpal, Priyanka; Chugh, Vishal; Kumar, Sundip; Prasad, Ramasare; Dhaliwal, Harcharan Singh

    2016-03-01

    Purpose To transfer the 2S chromosomal fragment(s) of Aegilops kotschyi (2S(k)) into the bread wheat genome which could lead to the biofortification of wheat with high grain iron and zinc content. Materials and methods Wheat-Ae. kotschyi 2A/2S(k) substitution lines with high grain iron and zinc content were used to transfer the gene/loci for high grain Fe and Zn content into wheat using seed irradiation approach. Results Bread wheat plants derived from 40 krad-irradiated seeds showed the presence of univalents and multivalents during meiotic metaphase-I. Genomic in situ hybridization analysis of seed irradiation hybrid F2 seedlings showed several terminal and interstitial signals indicated the introgression of Ae. kotschyi chromosome segments. This proves the efficacy of seed radiation hybrid approach in gene transfer experiments. All the radiation-treated hybrid plants with high grain Fe and Zn content were analyzed with wheat group 2 chromosome-specific polymorphic simple sequence repeat markers to identify the introgression of small alien chromosome fragment(s). Conclusion Radiation-induced hybrids showed more than 65% increase in grain iron and 54% increase in Zn contents with better harvest index than the elite wheat cultivar WL711 indicating effective and compensating translocations of 2S(k) fragments into wheat genome. PMID:26883304

  20. [Molecular cytogenetic identification of Aegilops ventricosa x Aegilops cylindrica amphiploid SDAU18].

    PubMed

    Wang, Yu Hai; Bao, Yin Guang; Hao, Yuan Feng; Yuan, Yuan Yuan; Zhao, Chun Hua; Wang, Qing Zhuan; Wang, Hong Gang

    2009-02-01

    SDAU18, an amphiploid of Ae.ventricosa with Ae.cylindrica, was identified by cytological analysis, seed storage protein electrophoresis, genomic in situ hybridization (GISH) and inoculation assessment. The results are as follows: The chromosome number of root tip cells (RTCs) of SDAU18 plants varied from 52 to 56. 28 bivalents were observed in most PMCs MI of SDAU18 with 56 chromosomes, meanwhile, a few univalents, multivalents also existed in some PMCs MI, and the average chromosome configuration was 2n = 56 = 3.21 I +19.78 II, (Ring)+6.50 II (Rod)+0.01 III +0.04 IV (Ring)R+0.01 IV (Rod). There were both Ae. ventricosa-specific bands and Ae. cylindrica-specific bands in the seed storage protein electrophoretogram of SDAU18, furthermore, SDAU18 had one novel HMW-GS not found in the parents and two novel ones not found in common wheats. By labeling the total genomic DNA of Ae. ventricosa and Ae. cylindrica as probes respectively, and using that of another parent as block, GISH of RTCs spread of SDAU18 was carried out. The green hybridization signal was observed in 14 chromosomes respectively, within 56 ones in RTCs of SDAU18. SDAU18 was immune to powdery mildew and stripe rusts. SDAU18 was an amphiploid of Ae. ventricosa with Ae. cylindrica, and had very important significance in wheat breeding and genetic improvement. PMID:19306684

  1. Accelerated evolution of the mitochondrial genome in an alloplasmic line of durum wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat is not only an important crop but also an excellent plant species for nuclear mitochondrial interaction studies. To investigate the level of sequence changes introduced into the mitochondrial genome under the alloplasmic conditions, three mitochondrial genomes of Triticum-Aegilops species w...

  2. 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

  3. Complete characterization of wheat-alien metaphase I pairing in interspecific hybrids between durum wheat (Triticum turgidum L.) and jointed goatgrass (Aegilops cylindrica Host).

    PubMed

    Cifuentes, Marta; Benavente, Elena

    2009-05-01

    The pattern of homoeologous metaphase I (MI) pairing has been fully characterized in durum wheat x Aegilops cylindrica hybrids (2n = 4x = 28, ABC(c)D(c)) by an in situ hybridization procedure that has permitted individual discrimination of every wheat and wild constituent genome. One of the three hybrid genotypes examined carried the ph1c mutation. In all cases, MI associations between chromosomes of both species represented around two-third of total. Main results from the analysis are as follows (a) the A genome chromosomes are involved in wheat-wild MI pairing more frequently than the B genome partners, irrespective of the alien genome considered; (b) both durum wheat genomes pair preferentially with the D(c) genome of jointed goatgrass. These findings are discussed in relation to the potential of genetic transference between wheat crops and this weedy relative. It can also be highlighted that inactivation of Ph1 provoked a relatively higher promotion of MI associations involving B genome. PMID:19319503

  4. RESISTANCE OF SHARON GOATGRASS (AEGILOPS SHARONENSIS) TO FUNGAL DISEASES OF WHEAT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sharon goatgrass (Aegilops sharonensis) is a wild relative of wheat that is native to Israel and Lebanon. The importance of Ae. sharonensis as a source of new resistance genes for wheat warrants additional research on the characterization of accessions for economically important genes. Thus, the obj...

  5. Introgression of a New Stem Rust Resistance Gene from Aegilops markgrafii into Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In a prior study, we reported that an Alcedo/Aegilops markgrafii disomic addition line, AIII(D) (2n=44), was resistant to three races of the Ug99 lineage and five North American races of stem rust pathogen in wheat and the resistance originated from the alien chromosome. In this study, our objectiv...

  6. New source of TTKSK resistance derived from Thinopyrum and Aegilops species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Several stem rust resistance genes of Thinopyrum and Aegilops origins appeared to be highly effective against race TTKSK (or Ug99) of Puccinia graminis f. sp. tritici. We evaluated and characterized the seedling resistance to TTKSK of 62 wheat lines derived from crosses of common or durum wheat with...

  7. A cryptic wheat–Aegilops triuncialis translocation with leaf rust resistance gene Lr58

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genes transferred to crop plants from wild species are often associated with deleterious traits. Using molecular markers, we detected a cryptic introgression with a leaf rust resistance gene transferred from Aegilops triuncialis L. into common wheat (Triticum aestivum L.). One agronomically desirabl...

  8. De novo assembly and characterization of the root transcriptome of Aegilops variabilis during an interaction with the cereal cyst nematode

    PubMed Central

    2012-01-01

    Background Aegilops variabilis No.1 is highly resistant to cereal cyst nematode (CCN). However, a lack of genomic information has restricted studies on CCN resistance genes in Ae. variabilis and has limited genetic applications in wheat breeding. Results Using RNA-Seq technology, we generated a root transcriptome at a sequencing depth of 4.69 gigabases of Ae. variabilis No. 1 from a pooled RNA sample. The sample contained equal amounts of RNA extracted from CCN-infected and untreated control plants at three time-points. Using the Trinity method, nearly 52,081,238 high-quality trimmed reads were assembled into a non-redundant set of 118,064 unigenes with an average length of 500 bp and an N50 of 599 bp. The total assembly was 59.09 Mb of unique transcriptome sequences with average read-depth coverage of 33.25×. In BLAST searches of our database against public databases, 66.46% (78,467) of the unigenes were annotated with gene descriptions, conserved protein domains, or gene ontology terms. Functional categorization further revealed 7,408 individual unigenes and three pathways related to plant stress resistance. Conclusions We conducted high-resolution transcriptome profiling related to root development and the response to CCN infection in Ae. variabilis No.1. This research facilitates further studies on gene discovery and on the molecular mechanisms related to CCN resistance. PMID:22494814

  9. 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

  10. Genome-wide association for grain morphology in synthetic hexaploid wheats using digital imaging analysis

    PubMed Central

    2014-01-01

    Background Grain size and shape greatly influence grain weight which ultimately enhances grain yield in wheat. Digital imaging (DI) based phenomic characterization can capture the three dimensional variation in grain size and shape than has hitherto been possible. In this study, we report the results from using digital imaging of grain size and shape to understand the relationship among different components of this trait, their contribution to enhance grain weight, and to identify genomic regions (QTLs) controlling grain morphology using genome wide association mapping with high density diversity array technology (DArT) and allele-specific markers. Results Significant positive correlations were observed between grain weight and grain size measurements such as grain length (r = 0.43), width, thickness (r = 0.64) and factor from density (FFD) (r = 0.69). A total of 231 synthetic hexaploid wheats (SHWs) were grouped into five different sub-clusters by Bayesian structure analysis using unlinked DArT markers. Linkage disequilibrium (LD) decay was observed among DArT loci > 10 cM distance and approximately 28% marker pairs were in significant LD. In total, 197 loci over 60 chromosomal regions and 79 loci over 31 chromosomal regions were associated with grain morphology by genome wide analysis using general linear model (GLM) and mixed linear model (MLM) approaches, respectively. They were mainly distributed on homoeologous group 2, 3, 6 and 7 chromosomes. Twenty eight marker-trait associations (MTAs) on the D genome chromosomes 2D, 3D and 6D may carry novel alleles with potential to enhance grain weight due to the use of untapped wild accessions of Aegilops tauschii. Statistical simulations showed that favorable alleles for thousand kernel weight (TKW), grain length, width and thickness have additive genetic effects. Allelic variations for known genes controlling grain size and weight, viz. TaCwi-2A, TaSus-2B, TaCKX6-3D and TaGw2-6A, were also associated

  11. Characterisation and Analysis of the Aegilops sharonensis Transcriptome, a Wild Relative of Wheat in the Sitopsis Section

    PubMed Central

    Bouyioukos, Costas; Moscou, Matthew J.; Champouret, Nicolas; Hernández-Pinzón, Inmaculada; Ward, Eric R.; Wulff, Brande B. H.

    2013-01-01

    Aegilopssharonensis Eig (Sharon goatgrass) is a wild diploid relative of wheat within the Sitopsis section of Aegilops. This species represents an untapped reservoir of genetic diversity for traits of agronomic importance, especially as a source of novel disease resistance. To gain a foothold in this genetic resource, we sequenced the cDNA from leaf tissue of two geographically distinct Ae. sharonensis accessions (1644 and 2232) using the 454 Life Sciences platform. We compared the results of two different assembly programs using different parameter sets to generate 13 distinct assemblies in an attempt to maximize representation of the gene space in de novo transcriptome assembly. The most sensitive assembly (71,029 contigs; N50 674 nts) retrieved 18,684 unique best reciprocal BLAST hits (BRBH) against six previously characterised grass proteomes while the most specific assembly (30,609 contigs; N50 815 nts) retrieved 15,687 BRBH. We combined these two assemblies into a set of 62,243 non-redundant sequences and identified 139 belonging to plant disease resistance genes of the nucleotide binding leucine-rich repeat class. Based on the non-redundant sequences, we predicted 37,743 single nucleotide polymorphisms (SNP), equivalent to one per 1,142 bp. We estimated the level of heterozygosity as 1.6% in accession 1644 and 30.1% in 2232. The Ae. sharonensis leaf transcriptome provides a rich source of sequence and SNPs for this wild wheat relative. These sequences can be used with existing monocot genome sequences and EST sequence collections (e.g. barley, Brachypodium, wheat, rice, maize and Sorghum) to assist with genetic and physical mapping and candidate gene identification in Ae. sharonensis. These resources provide an initial framework to further build on and characterise the genetic and genomic structure of Ae. sharonensis. PMID:23951332

  12. 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

  13. Exploring the tertiary gene pool of bread wheat: sequence assembly and analysis of chromosome 5M(g) of Aegilops geniculata.

    PubMed

    Tiwari, Vijay K; Wang, Shichen; Danilova, Tatiana; Koo, Dal Hoe; Vrána, Jan; Kubaláková, Marie; Hribova, Eva; Rawat, Nidhi; Kalia, Bhanu; Singh, Narinder; Friebe, Bernd; Doležel, Jaroslav; Akhunov, Eduard; Poland, Jesse; Sabir, Jamal S M; Gill, Bikram S

    2015-11-01

    Next-generation sequencing (NGS) provides a powerful tool for the discovery of important genes and alleles in crop plants and their wild relatives. Despite great advances in NGS technologies, whole-genome shotgun sequencing is cost-prohibitive for species with complex genomes. An attractive option is to reduce genome complexity to a single chromosome prior to sequencing. This work describes a strategy for studying the genomes of distant wild relatives of wheat by isolating single chromosomes from addition or substitution lines, followed by chromosome sorting using flow cytometry and sequencing of chromosomal DNA by NGS technology. We flow-sorted chromosome 5M(g) from a wheat/Aegilops geniculata disomic substitution line [DS5M(g) (5D)] and sequenced it using an Illumina HiSeq 2000 system at approximately 50 × coverage. Paired-end sequences were assembled and used for structural and functional annotation. A total of 4236 genes were annotated on 5M(g) , in close agreement with the predicted number of genes on wheat chromosome 5D (4286). Single-gene FISH indicated no major chromosomal rearrangements between chromosomes 5M(g) and 5D. Comparing chromosome 5M(g) with model grass genomes identified synteny blocks in Brachypodium distachyon, rice (Oryza sativa), sorghum (Sorghum bicolor) and barley (Hordeum vulgare). Chromosome 5M(g) -specific SNPs and cytogenetic probe-based resources were developed and validated. Deletion bin-mapped and ordered 5M(g) SNP markers will be useful to track 5M-specific introgressions and translocations. This study provides a detailed sequence-based analysis of the composition of a chromosome from a distant wild relative of bread wheat, and opens up opportunities to develop genomic resources for wild germplasm to facilitate crop improvement. PMID:26408103

  14. Molecular marker-assisted alien gene introgression of Sr39 for wheat stem rust resistance derived from Aegilops speltoides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In wheat (Triticum aestivum L.), stem rust resistance gene Sr39, derived from Aegilops speltoides, is highly effective against multiple stem rust races including Ug99. However, the gene has not been used in wheat breeding because it is located on a large 2S chromosomal segment in the current transl...

  15. Introgression of leaf rust and stripe rust resistance from Sharon goatgrass (Aegilops sharonensis Eig) into bread wheat (Triticum aestivum L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leaf rust and stripe rust are devastating wheat diseases, causing significant yield losses in many regions of the world. The use of resistant varieties is the most efficient way to protect wheat crops from these diseases. Sharon goatgrass (Aegilops sharonensis or AES), which is a diploid wild relati...

  16. 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

  17. [The effect of the genome of the variety on the adaptive characteristics of alloplasmic strains of winter wheat].

    PubMed

    Simonenko, V K; Khangil'din, V V; Vlasenko, V A

    2000-01-01

    The analysis of adaptability and genetical distances between 12 cytoplasms of Aegilops, Triticum and Haynaldia villosa for three winter wheat genomes showed an existence of genome-plasmon interactions. The plasmons of Ae. variabilis, Ae. cylindrica, Ae. squarrosa var. strangulata, T. dicoccoides appeared to be perspective in practical breeding for adaptability. Interactions are revealed as alteration of productivity and adaptability, and as genetic divergence. PMID:10920857

  18. [The detection of nonallelic to known genes of resistance to Tilletia caries (DC) Tul. in wheat strains from interspecific hybridization (Triticum aestivum x Aegilops cylindrica)].

    PubMed

    Babaiants, L T; Dubinina, L A; Iushchenko, G M

    2000-01-01

    It was established by hybridological analysis that winter bread wheat lines 1/74-91, 3/36-91, 5/55-91 possess single dominant gene of resistance to bunt (Tilletia caries (DC) Tul.), but lines 8/2-91, 5/43-91, 4/11-91 and 8/16-91 have two independent dominant genes for this character. These genes originated from Aegilops cylindrica are not identical to Bt1-Bt17 genes and are unknown to date. The lines were obtained from crosses between winter bread wheat variety Odeskaya polukarlikovaya and Aegilops cylindrica. PMID:11033855

  19. Genetic differentiation and post-glacial establishment of the geographical distribution in Aegilops caudata L.

    PubMed

    Ohta, S

    2000-08-01

    Aegilops caudata L. is a diploid wild relative of wheat distributed over the north-eastern Mediterranean from Greece to northern Iraq. To elucidate the geographical differentiation pattern, 35 accessions derived from the entire distribution area were crossed with four Tester strains. Pollen fertility in the F1 hybrids varied from 0 to 96.3% among cross combinations, closely correlating with the geographical regions where the parental accessions were collected. Based on the intraspecific hybrid sterility, the present distribution area of Ae. caudata was divided into two geographical regions effectively isolated by the mountainous region lying between West Anatolia and Central Anatolia. The western region is composed of Greece and West Anatolia, while the eastern region consists of Central Anatolia, South Anatolia, East Anatolia and northern Iraq. The present results and the facts from recent palaeopalynological works suggest that during the maximum glacial period from 18,000 BP to 16,000 BP, Ae. caudata occurred in the two isolated regions, i.e., the region surrounding the Aegean Sea and the western Levant or some sheltered habitats in the East Taurus/Zagros mountains arc, and that it migrated into Central and East Anatolia from the latter regions as the climate became warmer. Furthermore, it is also suggested that the Levant populations now occur in the eastern region of the distribution, while those occurring in the Aegean Sea region during the last glacial period now occupy the western region of the distribution. PMID:11126567

  20. Diversity of fungal endophytes in recent and ancient wheat ancestors Triticum dicoccoides and Aegilops sharonensis.

    PubMed

    Ofek-Lalzar, Maya; Gur, Yonatan; Ben-Moshe, Sapir; Sharon, Or; Kosman, Evsey; Mochli, Elad; Sharon, Amir

    2016-10-01

    Endophytes have profound impacts on plants, including beneficial effects on agriculturally important traits. We hypothesized that endophytes in wild plants include beneficial endophytes that are absent or underrepresented in domesticated crops. In this work, we studied the structure of endophyte communities in wheat-related grasses, Triticum dicoccoides and Aegilops sharonensis, and compared it to an endophyte community from wheat (T. aeastivum). Endophytes were isolated by cultivation and by cultivation-independent methods. In total, 514 intergenic spacer region sequences from single cultures were analyzed. Categorization at 97% sequence similarity resulted in 67 operational taxonomic units (OTUs) that were evenly distributed between the different plant species. A narrow core community of Alternaria spp. was found in all samples, but each plant species also contained a significant portion of unique endophytes. The cultivation-independent analysis identified a larger number of OTUs than the cultivation method, half of which were singletons or doubletons. For OTUs with a relative abundance >0.5%, similar numbers were obtained by both methods. Collectively, our data show that wild grass relatives of wheat contain a wealth of taxonomically diverse fungal endophytes that are not found in modern wheat, some of which belong to taxa with known beneficial effects. PMID:27402714

  1. Partial characterization of glutathione S-transferases from wheat (Triticum spp.) and purification of a safener-induced glutathione S-transferase from Triticum tauschii.

    PubMed Central

    Riechers, D E; Irzyk, G P; Jones, S S; Fuerst, E P

    1997-01-01

    Hexaploid wheat (Triticum aestivum L.) has very low constitutive glutathione S-transferase (GST) activity when assayed with the chloroacetamide herbicide dimethenamid as a substrate, which may account for its low tolerance to dimethenamid in the field. Treatment of seeds with the herbicide safener fluxofenim increased the total GST activity extracted from T. aestivum shoots 9-fold when assayed with dimethenamid as a substrate, but had no effect on glutathione levels. Total GST activity in crude protein extracts from T. aestivum, Triticum durum, and Triticum tauschii was separated into several component GST activities by anion-exchange fast-protein liquid chromatography. These activities (isozymes) differed with respect to their activities toward dimethenamid or 1-chloro-2,4-dinitrobenzene as substrates and in their levels of induction by safener treatment. A safener-induced GST isozyme was subsequently purified by anion-exchange and affinity chromatography from etiolated shoots of the diploid wheat species T. tauschii (a progenitor of hexaploid wheat) treated with the herbicide safener cloquintocet-mexyl. The isozyme bound to a dimethenamid-affinity column and had a subunit molecular mass of 26 kD based on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The purified enzyme (designated GST TSI-1) was recognized by an antiserum raised against a mixture of maize (Zea mays) GSTs. Amino acid sequences obtained from protease-digested GST TSI-1 had significant homology with the safener-inducible maize GST V and two auxin-regulated tobacco (Nicotiana tabacum) GST isozymes. PMID:9276955

  2. [Effect of an introgression from Aegilops cylindrica host on manifestation of productivity traits in winter common wheat F2 plants].

    PubMed

    Kozub, N A; Sozinov, I A; sozinov, A A

    2004-12-01

    The effect of introgression of a chromosome 1D segment from Aegilops cylindrica to winter common wheat on productivity traits in F2 plants was studied using storage protein loci as genetic markers. An allele of the gliadin-coding Gli-D1 locus served as a marker of the introgression. Using of two- and three-locus interaction models, it was shown that the introgression tagged with Gli-D1 affected the manifestation of productivity traits (productive tillering, grain weight per plant and grain number per plant) through interaction with other marker storage protein loci: Glu-B1, Glu-D1, and Gli-B2. PMID:15648149

  3. The chloroplast view of the evolution of polyploid wheat.

    PubMed

    Gornicki, Piotr; Zhu, Huilan; Wang, Junwei; Challa, Ghana S; Zhang, Zhengzhi; Gill, Bikram S; Li, Wanlong

    2014-11-01

    Polyploid wheats comprise four species: Triticum turgidum (AABB genomes) and T. aestivum (AABBDD) in the Emmer lineage, and T. timopheevii (AAGG) and T. zhukovskyi (AAGGA(m) A(m) ) in the Timopheevi lineage. Genetic relationships between chloroplast genomes were studied to trace the evolutionary history of the species. Twenty-five chloroplast genomes were sequenced, and 1127 plant accessions were genotyped, representing 13 Triticum and Aegilops species. The A. speltoides (SS genome) diverged before the divergence of T. urartu (AA), A. tauschii (DD) and the Aegilops species of the Sitopsis section. Aegilops speltoides forms a monophyletic clade with the polyploid Emmer and Timopheevi wheats, which originated within the last 0.7 and 0.4 Myr, respectively. The geographic distribution of chloroplast haplotypes of the wild tetraploid wheats and A. speltoides illustrates the possible geographic origin of the Emmer lineage in the southern Levant and the Timopheevi lineage in northern Iraq. Aegilops speltoides is the closest relative of the diploid donor of the chloroplast (cytoplasm), as well as the B and G genomes to Timopheevi and Emmer lineages. Chloroplast haplotypes were often shared by species or subspecies within major lineages and between the lineages, indicating the contribution of introgression to the evolution and domestication of polyploid wheats. PMID:25059383

  4. Characterization and mapping of cryptic alien introgression from Aegilops geniculata with new leaf rust and stripe rust resistance genes Lr57 and Yr40 in wheat.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leaf rust and stripe rust are important foliar diseases of wheat worldwide. Leaf rust and stripe rust resistant introgression lines were developed by induced homoeologous chromosome pairing between wheat chromosome 5D and 5Mg of Aegilops geniculata (UgMg). Characterization of rust resistant BC2F5 a...

  5. Development of wheat-Aegilops speltoides recombinants and simple PCR-based markers for stem rust resistance genes on the 2S#1 chromosome

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wild relatives of wheat are important but underutilized resources for new rust resistance genes because linked negative traits often hinder deployment of these genes in commercial wheats. Here we report reduced alien chromatin recombinants derived from E.R. Sears wheat-Aegilops speltoides translocat...

  6. Development of a diagnostic co-dominant marker for stem rust resistance gene Sr47 introgressed from Aegilops speltoides into durum wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stem rust (caused by Puccinia graminis f. sp. tritici, abbreviated as Pgt) resistance gene Sr47, originally transferred from Aegilops speltoides to durum wheat (Triticum turgidum subsp. durum) line DAS15, confers a high level of resistance to Pgt race TTKSK (known as Ug99). Recently, the durum Rust...

  7. Development of wheat-Aegilops speltoides recombinants and simple PCR-based markers for stem rust resistance genes on the 2S#1 chromosome

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wild relatives of wheat are important but underutilized resources for new rust resistance genes because linked negative traits often hinder deployment of these genes in commercial wheats. Here we report reduced alien chromatin recombinants derived from E.R. Sears' wheat-Aegilops speltoides transloca...

  8. Genetic Basis for Spontaneous Hybrid Genome Doubling during Allopolyploid Speciation of Common Wheat Shown by Natural Variation Analyses of the Paternal Species

    PubMed Central

    Matsuoka, Yoshihiro; Nasuda, Shuhei; Ashida, Yasuyo; Nitta, Miyuki; Tsujimoto, Hisashi; Takumi, Shigeo; Kawahara, Taihachi

    2013-01-01

    The complex process of allopolyploid speciation includes various mechanisms ranging from species crosses and hybrid genome doubling to genome alterations and the establishment of new allopolyploids as persisting natural entities. Currently, little is known about the genetic mechanisms that underlie hybrid genome doubling, despite the fact that natural allopolyploid formation is highly dependent on this phenomenon. We examined the genetic basis for the spontaneous genome doubling of triploid F1 hybrids between the direct ancestors of allohexaploid common wheat (Triticum aestivum L., AABBDD genome), namely Triticumturgidum L. (AABB genome) and Aegilopstauschii Coss. (DD genome). An Ae. tauschii intraspecific lineage that is closely related to the D genome of common wheat was identified by population-based analysis. Two representative accessions, one that produces a high-genome-doubling-frequency hybrid when crossed with a T. turgidum cultivar and the other that produces a low-genome-doubling-frequency hybrid with the same cultivar, were chosen from that lineage for further analyses. A series of investigations including fertility analysis, immunostaining, and quantitative trait locus (QTL) analysis showed that (1) production of functional unreduced gametes through nonreductional meiosis is an early step key to successful hybrid genome doubling, (2) first division restitution is one of the cytological mechanisms that cause meiotic nonreduction during the production of functional male unreduced gametes, and (3) six QTLs in the Ae. tauschii genome, most of which likely regulate nonreductional meiosis and its subsequent gamete production processes, are involved in hybrid genome doubling. Interlineage comparisons of Ae. tauschii’s ability to cause hybrid genome doubling suggested an evolutionary model for the natural variation pattern of the trait in which non-deleterious mutations in six QTLs may have important roles. The findings of this study demonstrated that the

  9. Genome-Wide Analysis of Stowaway-Like MITEs in Wheat Reveals High Sequence Conservation, Gene Association, and Genomic Diversification1[C][W

    PubMed Central

    Yaakov, Beery; Ben-David, Smadar; Kashkush, Khalil

    2013-01-01

    The diversity and evolution of wheat (Triticum-Aegilops group) genomes is determined, in part, by the activity of transposable elements that constitute a large fraction of the genome (up to 90%). In this study, we retrieved sequences from publicly available wheat databases, including a 454-pyrosequencing database, and analyzed 18,217 insertions of 18 Stowaway-like miniature inverted-repeat transposable element (MITE) families previously characterized in wheat that together account for approximately 1.3 Mb of sequence. All 18 families showed high conservation in length, sequence, and target site preference. Furthermore, approximately 55% of the elements were inserted in transcribed regions, into or near known wheat genes. Notably, we observed significant correlation between the mean length of the MITEs and their copy number. In addition, the genomic composition of nine MITE families was studied by real-time quantitative polymerase chain reaction analysis in 40 accessions of Triticum spp. and Aegilops spp., including diploids, tetraploids, and hexaploids. The quantitative polymerase chain reaction data showed massive and significant intraspecific and interspecific variation as well as genome-specific proliferation and nonadditive quantities in the polyploids. We also observed significant differences in the methylation status of the insertion sites among MITE families. Our data thus suggest a possible role for MITEs in generating genome diversification and in the establishment of nascent polyploid species in wheat. PMID:23104862

  10. Wheat phylogeny determined by RFLP analysis of nuclear DNA. 3. Intra- and interspecific variations of five Aegilops Sitopsis species.

    PubMed

    Sasanuma, T; Miyashita, N T; Tsunewaki, K

    1996-06-01

    The level of intra- and interspecific variations on nuclear DNA in five Aegilops species of the Sitopsis section were investigated using restriction fragment length polymorphism (RFLP) analysis. A total of 18 accessions, i.e. 7 of Ae. speltoides, 3 of Ae. longissima, 2 of Ae. searsii, 3 of Ae. sharonensis and 3 of Ae. bicornis, were used. One accession each of Triticum aestivum, T. durum, T. urartu and Ae. squarrosa was included as reference material. Five enzymes and 20 probes were used. Among the five Sitopsis species studied, Ae. speltoides had the largest intraspecific variation (π=0.061), which was as high as the interspecific variation observed among the other four species. The section Sitopsis was divided into two distinct groups: one containing only Ae. speltoides and the other, Ae. longissima, Ae. searsii, Ae. sharonensis and Ae. bicornis. This grouping by RFLP analysis is in agreement with the taxonomical classification of the subsections. PMID:24166619

  11. [Molecular marker mapping of the gene resistant to common bunt transferred from Aegilops cylindrica into bread wheat].

    PubMed

    Galaev, A V; Babaiants, L T; Sivolap, Iu M

    2006-01-01

    Introgression lines 5/55-91 and 378/2000 of bread wheat contain the gene of resistance to Tilletia caries (DC.) Tul. transferred from Aegilops cylindrica Host. Using bulked segregant analysis with ISSR and SSR PCR the lincage of microsatellite locus Xgwm 259 with the gene of common bunt resistance has been identified in F2 population of 378/2000 x Lutestens 23397. DNA mapping made it possible to localize this highly effective gene in the intercalary region of the long arm of wheat chromosome 1B at the distance of 7.6-8.5 cM of the microsatellite Xgwm 259 locus which thus can be used in wheat breeding for selection of genotype resistance to common bunt. PMID:16865982

  12. 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

  13. 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

  14. Characterization of a new wheat-Aegilops biuncialis addition line conferring quality-associated HMW glutenin subunits.

    PubMed

    Zhou, J P; Yao, C H; Yang, E N; Yin, M Q; Liu, C; Ren, Z L

    2014-01-01

    In this study, a new disomic addition line, 12-5-2, with 44 chromosomes that was derived from BC3F2 descendants of the hybridization between Triticum aestivum cv. CN19 and Aegilops biuncialis was created and reported. 12-5-2 was immune to both powdery mildew and stripe rust and has stable fertility. Fluorescence in situ hybridization and C-banding revealed that 12-5-2 was a 1U(b) disomic addition line (ADL1U(b)). The seed storage protein electrophoresis showed that 12-5-2 presented all high molecular weight glutenin subunits (7 + 8 and 2 + 12) of CN19 and 2 new subunits that were designated Ux and Uy. Additionally, the flour quality parameters showed that the protein content, Zeleny sedimentation value, wet gluten content, and grain hardness of 12-5-2 were significantly higher than those of its parent CN19. Moreover, 5 pairs of the chromosome 1U(b)-specific polymerase chain reaction-based landmark unique gene markers, TNAC1021, TNAC1041, TNAC1071, TNAC1-01, and TNAC1-04, were also obtained. The new ADL1U(b) 12-5-2 could be a valuable source for wheat improvement, especially for wheat end-product quality and resistance to disease. PMID:24615031

  15. Haploid production in durum wheat by the interaction of Aegilops kotschyi cytoplasm and 1BL/1RS chromosomal interchange.

    PubMed

    Hsam, S L; Zeller, F J

    1993-09-01

    The present study describes the development of an alloplasmic haploid-inducer in durum wheat cv 'Cando'. This cultivar possesses the homozygous wheat-rye translocation 1BL/1RS from the 6x-wheat cv 'Veery'. The nucleus of 4x-'Cando-Veery 1BL/1RS' was introduced into Aegilops kotschyi cytoplasm by initially using (kotschyi)-Salmon as the maternal parent. In the cross of this alloplasmic durum line with 'Cando-Veery 1BL/1RS', which was used as the recurrent pollen parent, haploids (n=14) were produced. The frequency of haploids increased from 5.7% in the F1 generation to 14% in the BC1 generation. The presence of rye chromosome arm 1RS and the concomitant loss of 1BS in '(kotschyi)-Cando-Veery 1BL/1RS' are necessary for haploid induction. Proposals are made which may enable the use of haploids produced by nucleo-cytoplasmic interactions in future wheat breeding programs. PMID:24194002

  16. Introgression of leaf rust and stripe rust resistance from Sharon goatgrass (Aegilops sharonensis Eig) into bread wheat (Triticum aestivum L.).

    PubMed

    Millet, E; Manisterski, J; Ben-Yehuda, P; Distelfeld, A; Deek, J; Wan, A; Chen, X; Steffenson, B J

    2014-06-01

    Leaf rust and stripe rust are devastating wheat diseases, causing significant yield losses in many regions of the world. The use of resistant varieties is the most efficient way to protect wheat crops from these diseases. Sharon goatgrass (Aegilops sharonensis or AES), which is a diploid wild relative of wheat, exhibits a high frequency of leaf and stripe rust resistance. We used the resistant AES accession TH548 and induced homoeologous recombination by the ph1b allele to obtain resistant wheat recombinant lines carrying AES chromosome segments in the genetic background of the spring wheat cultivar Galil. The gametocidal effect from AES was overcome by using an "anti-gametocidal" wheat mutant. These recombinant lines were found resistant to highly virulent races of the leaf and stripe rust pathogens in Israel and the United States. Molecular DArT analysis of the different recombinant lines revealed different lengths of AES segments on wheat chromosome 6B, which indicates the location of both resistance genes. PMID:25209724

  17. Variation and geographical distribution of the genotypes controlling the diagnostic spike morphology of two varieties of Aegilops caudata l.

    PubMed

    Ohta, S

    2001-10-01

    Aegilops caudata L. is an annual wild relative of wheat distributed over the northeastern Mediterranean basin. It consists of two taxonomic varieties, var. typica with awnless lateral spikelets and var.polyathera with awned lateral spikelets. To clarify the variation and the geographical distribution of the genotypes controlling the diagnostic spike morphology of the two taxonomic varieties, three crossing experiments were carried out. First, two varieties collected from nine sympatric populations in the Aegean islands were crossed reciprocally. All of the F1 hybrids were var. typica and the segregation ratio in the F2 generation was 3 typica: 1 polyathera. Secondly, 13 typica accessions collected from the entire distribution area of the variety were crossed with a common polyathera accession. The F1 hybrids involving eight typica accessions from Greece and West Anatolia were var. typica, while those involving five typica accessions from East Anatolia, Syria and Iraq were var. polyathera. Thirdly, the typica F1 hybrids between the Aegean and the Syrian typica accessions were backcrossed to the latter. Four of the seven BC1F1 plants obtained were var. typica, but the other three were var. polyathera. Based on these results, the following two conclusions were made. First, the awnless lateral spikelets characteristic of var. typica are due to two different genotypes: one is a dominant allele suppressing awn development on lateral spikelets and the other is a recessive allele(s) for awnless lateral spikelets with no dominant suppressor allele. Secondly, the former genotype occurs only in the western region of the distribution area of the species, while the latter occurs in the eastern region. The present results and the recent palaeopalynological evidence also suggested that var. polyathera, with more awns than var. typica, rapidly colonized Central Anatolia from the Levant or East Taurus/Zagros mountains arc after the last glacial period. PMID:11817646

  18. Identification of a 5S rDNA spacer type specific Triticum urartu and wheats containing the T. urartu genome.

    PubMed

    Allaby, R G; Brown, T A

    2000-04-01

    A PCR system was designed to amplify 5S spacer rDNA specifically from homeologous chromosome 1 in a variety of species representative of the Aegilops and Triticum genera. Two polymerase chain reaction (PCR) primer combinations were used, one of which appears to be apomorphic in nature and specific to chromosome 1A in Triticum urartu and tetraploid and hexaploid wheats containing the AA genome donated by T. urartu. The value of studying single repeat types to investigate the molecular evolution of 5S-rDNA arrays is considered. PMID:10791812

  19. Potential Implications of Climate Change on Aegilops Species Distribution: Sympatry of These Crop Wild Relatives with the Major European Crop Triticum aestivum and Conservation Issues

    PubMed Central

    Prosperi, Jean-Marie; David, Jacques

    2016-01-01

    Gene flow from crop to wild relatives is a common phenomenon which can lead to reduced adaptation of the wild relatives to natural ecosystems and/or increased adaptation to agrosystems (weediness). With global warming, wild relative distributions will likely change, thus modifying the width and/or location of co-occurrence zones where crop-wild hybridization events could occur (sympatry). This study investigates current and 2050 projected changes in sympatry levels between cultivated wheat and six of the most common Aegilops species in Europe. Projections were generated using MaxEnt on presence-only data, bioclimatic variables, and considering two migration hypotheses and two 2050 climate scenarios (RCP4.5 and RCP8.5). Overall, a general decline in suitable climatic conditions for Aegilops species outside the European zone and a parallel increase in Europe were predicted. If no migration could occur, the decline was predicted to be more acute outside than within the European zone. The potential sympatry level in Europe by 2050 was predicted to increase at a higher rate than species richness, and most expansions were predicted to occur in three countries, which are currently among the top four wheat producers in Europe: Russia, France and Ukraine. The results are also discussed with regard to conservation issues of these crop wild relatives. PMID:27100790

  20. Potential Implications of Climate Change on Aegilops Species Distribution: Sympatry of These Crop Wild Relatives with the Major European Crop Triticum aestivum and Conservation Issues.

    PubMed

    Ostrowski, Marie-France; Prosperi, Jean-Marie; David, Jacques

    2016-01-01

    Gene flow from crop to wild relatives is a common phenomenon which can lead to reduced adaptation of the wild relatives to natural ecosystems and/or increased adaptation to agrosystems (weediness). With global warming, wild relative distributions will likely change, thus modifying the width and/or location of co-occurrence zones where crop-wild hybridization events could occur (sympatry). This study investigates current and 2050 projected changes in sympatry levels between cultivated wheat and six of the most common Aegilops species in Europe. Projections were generated using MaxEnt on presence-only data, bioclimatic variables, and considering two migration hypotheses and two 2050 climate scenarios (RCP4.5 and RCP8.5). Overall, a general decline in suitable climatic conditions for Aegilops species outside the European zone and a parallel increase in Europe were predicted. If no migration could occur, the decline was predicted to be more acute outside than within the European zone. The potential sympatry level in Europe by 2050 was predicted to increase at a higher rate than species richness, and most expansions were predicted to occur in three countries, which are currently among the top four wheat producers in Europe: Russia, France and Ukraine. The results are also discussed with regard to conservation issues of these crop wild relatives. PMID:27100790

  1. QTug.sau-3B Is a Major Quantitative Trait Locus for Wheat Hexaploidization

    PubMed Central

    Hao, Ming; Luo, Jiangtao; Zeng, Deying; Zhang, Li; Ning, Shunzong; Yuan, Zhongwei; Yan, Zehong; Zhang, Huaigang; Zheng, Youliang; Feuillet, Catherine; Choulet, Frédéric; Yen, Yang; Zhang, Lianquan; Liu, Dengcai

    2014-01-01

    Meiotic nonreduction resulting in unreduced gametes is thought to be the predominant mechanism underlying allopolyploid formation in plants. Until now, however, its genetic base was largely unknown. The allohexaploid crop common wheat (Triticum aestivum L.), which originated from hybrids of T. turgidum L. with Aegilops tauschii Cosson, provides a model to address this issue. Our observations of meiosis in pollen mother cells from T. turgidum×Ae. tauschii hybrids indicated that first division restitution, which exhibited prolonged cell division during meiosis I, was responsible for unreduced gamete formation. A major quantitative trait locus (QTL) for this trait, named QTug.sau-3B, was detected on chromosome 3B in two T. turgidum×Ae. tauschii haploid populations. This QTL is situated between markers Xgwm285 and Xcfp1012 and covered a genetic distance of 1 cM in one population. QTug.sau-3B is a haploid-dependent QTL because it was not detected in doubled haploid populations. Comparative genome analysis indicated that this QTL was close to Ttam-3B, a collinear homolog of tam in wheat. Although the relationship between QTug.sau-3B and Ttam requires further study, high frequencies of unreduced gametes may be related to reduced expression of Ttam in wheat. PMID:25128436

  2. Fat element-a new marker for chromosome and genome analysis in the Triticeae.

    PubMed

    Badaeva, Ekaterina D; Zoshchuk, Svyatoslav A; Paux, Etienne; Gay, Georges; Zoshchuk, Natalia V; Roger, Delphine; Zelenin, Alexander V; Bernard, Michel; Feuillet, Catherine

    2010-09-01

    Chromosomal distribution of the Fat element that was isolated from bacterial artificial chromosome (BAC) end sequences of wheat chromosome 3B was studied in 45 species representing eight genera of Poaceae (Aegilops, Triticum, Agropyron, Elymus, Secale, Hordeum, Avena and Triticale) using fluorescence in situ hybridisation (FISH). The Fat sequence was not present in oats and in two barley species, Hordeum vulgare and Hordeum spontaneum, that we investigated. Only very low amounts of the Fat element were detected on the chromosomes of two other barley species, Hordeum geniculatum and Hordeum chilense, with different genome compositions. The chromosomes of other cereal species exhibited distinct hybridisation patterns with the Fat probe, and labelling intensity varied significantly depending on the species or genome. The highest amount of hybridisation was detected on chromosomes of the D genome of Aegilops and Triticum and on chromosomes of the S genome of Agropyron. Despite the bioinformatics analysis of several BAC clones that revealed the tandem organisation of the Fat element, hybridisation with the Fat probe produces uneven, diffuse signals in the proximal regions of chromosomes. In some of the genomes we investigated, however, it also forms distinct, sharp clusters in chromosome-specific positions, and the brightest fluorescence was always observed on group 4 chromosomes. Thus, the Fat element represents a new family of Triticeae-specific, highly repeated DNA elements with a clustered-dispersed distribution pattern. These elements may have first emerged in cereal genomes at the time of divergence of the genus Hordeum from the last common ancestor. During subsequent evolution, the amount and chromosomal distribution of the Fat element changed due to amplification, elimination and re-distribution of this sequence. Because the labelling patterns that we detected were highly specific, the Fat element can be used as an accessory probe in FISH analysis for chromosome

  3. 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

  4. 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

  5. Biochemical data bearing on the relationship between the genome of Triticum urartu and the A and B genomes of the polyploid wheats.

    PubMed

    Kerby, K; Kuspira, J; Jones, B L

    1988-08-01

    To determine whether the Triticum urartu genome is more closely related to the A or B genome of the polyploid wheats, the amino acid sequence of its purothionin was compared to the amino acid sequences of the purothionins in Triticum monococcum, Triticum turgidum, and Triticum aestivum. The residue sequence of the purothionin from T. urartu differs by five and six amino acid substitutions respectively from the alpha 1 and alpha 2 forms coded for by genes in the B and D genomes, and is identical to the beta form specified by a gene in the A genome. Therefore, the T. urartu purothionin is either coded by a gene in the A genome or a chromosome set highly homologous to it. The results demonstrate that at least a portion of the T. urartu and T. monococcum genomes is homologous and probably identical. A variety of other studies have also shown that T. urartu is very closely related to T. monococcum and, in all likelihood, also possesses the A genome. Therefore, it could be argued that either T. urartu and T. monococcum are the same species or that T. urartu rather than T. monococcum is the source of the A genome in T. turgidum and T. aestivum. Except for Johnson's results, our data and that of others suggest a revised origin of polyploid wheats. Specifically, the list of six putative B genome donor species is reduced to five, all members of the Sitopsis section of the genus Aegilops. PMID:3209062

  6. Genetic variation of jointed goatgrass (Aegilops cylindrica Host.) from Iran using RAPD-PCR and SDS-PAGE of seed proteins.

    PubMed

    Farkhari, M; Naghavi, M R; Pyghambari, S A; Sabokdast

    2007-09-01

    Genetic variation of 28 populations of jointed goatgrass (Aegilops cylindrica Host.), collected from different parts of Iran, were evaluated using both RAPD-PCR and SDS-PAGE of seed proteins. The diversity within and between populations for the three-band High Molecular Weight (HMW) subunits of glutenin pattern were extremely low. Out of 15 screened primers of RAPD, 14 primers generated 133 reproducible fragments which among them 92 fragments were polymorphic (69%). Genetic similarity calculated from the RAPD data ranged from 0.64 to 0.98. A dendrogram was prepared on the basis of a similarity matrix using the UPGMA algorithm and separated the 28 populations into two groups. Confusion can happen between populations with the same origin as well as between populations of very diverse geographical origins. Our results show that compare to seed storage protein, RAPD is suitable for genetic diversity assessment in Ae. cylindrica populations. PMID:19090190

  7. Discovery and molecular mapping of a new gene conferring resistance to stem rust, Sr53, derived from Aegilops geniculata and characterization of spontaneous translocation stocks with reduced alien chromatin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study reports the discovery and molecular mapping of a resistance gene effective against stem rust races RKQQC and TTKSK (Ug99) derived from Aegilops geniculata (2n=4x=28, UgUgMgMg). Two populations from the crosses TA5599 (T5DL-5MgL.5MgS)/TA3809 (ph1b mutant in Chinese Spring background) and T...

  8. Synthesizing double haploid hexaploid wheat populations based on a spontaneous alloploidization process.

    PubMed

    Zhang, Lianquan; Zhang, Li; Luo, Jiangtao; Chen, Wenjie; Hao, Ming; Liu, Baolong; Yan, Zehong; Zhang, Bo; Zhang, Huaigang; Zheng, Youliang; Liu, Dengcai; Yen, Yang

    2011-02-01

    Doubled haploid (DH) populations are useful to scientists and breeders in both crop improvement and basic research. Current methods of producing DHs usually need in vitro culture for extracting haploids and chemical treatment for chromosome doubling. This report describes a simple method for synthesizing DHs (SynDH) especially for allopolyploid species by utilizing meiotic restitution genes. The method involves three steps: hybridization to induce recombination, interspecific hybridization to extract haploids, and spontaneous chromosome doubling by selfing the interspecific F(1)s. DHs produced in this way contain recombinant chromosomes in the genome(s) of interest in a homogeneous background. No special equipment or treatments are involved in the DH production and it can be easily applied in any breeding and/or genetic program. Triticum turgidum L. and Aegilops tauschii Coss, the two ancestral species of common wheat (Triticum aestivum L.) and molecular markers were used to demonstrate the SynDH method. PMID:21356528

  9. Genome reorganization in F1 hybrids uncovers the role of retrotransposons in reproductive isolation

    PubMed Central

    Senerchia, Natacha; Felber, François; Parisod, Christian

    2015-01-01

    Interspecific hybridization leads to new interactions among divergent genomes, revealing the nature of genetic incompatibilities having accumulated during and after the origin of species. Conflicts associated with misregulation of transposable elements (TEs) in hybrids expectedly result in their activation and genome-wide changes that may be key to species boundaries. Repetitive genomes of wild wheats have diverged under differential dynamics of specific long terminal repeat retrotransposons (LTR-RTs), offering unparalleled opportunities to address the underpinnings of plant genome reorganization by selfish sequences. Using reciprocal F1 hybrids between three Aegilops species, restructuring and epigenetic repatterning was assessed at random and LTR-RT sequences with amplified fragment length polymorphism and sequence-specific amplified polymorphisms as well as their methylation-sensitive counterparts, respectively. Asymmetrical reorganization of LTR-RT families predicted to cause conflicting interactions matched differential survival of F1 hybrids. Consistent with the genome shock model, increasing divergence of merged LTR-RTs yielded higher levels of changes in corresponding genome fractions and lead to repeated reorganization of LTR-RT sequences in F1 hybrids. Such non-random reorganization of hybrid genomes is coherent with the necessary repression of incompatible TE loci in support of hybrid viability and indicates that TE-driven genomic conflicts may represent an overlooked factor supporting reproductive isolation. PMID:25716787

  10. Genome reorganization in F1 hybrids uncovers the role of retrotransposons in reproductive isolation.

    PubMed

    Senerchia, Natacha; Felber, François; Parisod, Christian

    2015-04-01

    Interspecific hybridization leads to new interactions among divergent genomes, revealing the nature of genetic incompatibilities having accumulated during and after the origin of species. Conflicts associated with misregulation of transposable elements (TEs) in hybrids expectedly result in their activation and genome-wide changes that may be key to species boundaries. Repetitive genomes of wild wheats have diverged under differential dynamics of specific long terminal repeat retrotransposons (LTR-RTs), offering unparalleled opportunities to address the underpinnings of plant genome reorganization by selfish sequences. Using reciprocal F1 hybrids between three Aegilops species, restructuring and epigenetic repatterning was assessed at random and LTR-RT sequences with amplified fragment length polymorphism and sequence-specific amplified polymorphisms as well as their methylation-sensitive counterparts, respectively. Asymmetrical reorganization of LTR-RT families predicted to cause conflicting interactions matched differential survival of F1 hybrids. Consistent with the genome shock model, increasing divergence of merged LTR-RTs yielded higher levels of changes in corresponding genome fractions and lead to repeated reorganization of LTR-RT sequences in F1 hybrids. Such non-random reorganization of hybrid genomes is coherent with the necessary repression of incompatible TE loci in support of hybrid viability and indicates that TE-driven genomic conflicts may represent an overlooked factor supporting reproductive isolation. PMID:25716787

  11. 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

  12. 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

  13. 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

  14. Genome evolution in diploid and tetraploid Coffea species as revealed by comparative analysis of orthologous genome segments.

    PubMed

    Cenci, Alberto; Combes, Marie-Christine; Lashermes, Philippe

    2012-01-01

    Sequence comparison of orthologous regions enables estimation of the divergence between genomes, analysis of their evolution and detection of particular features of the genomes, such as sequence rearrangements and transposable elements. Despite the economic importance of Coffea species, little genomic information is currently available. Coffea is a relatively young genus that includes more than one hundred diploid species and a single tetraploid species. Three Coffea orthologous regions of 470-900 kb were analyzed and compared: both subgenomes of allotetraploid Coffea arabica (contributed by the diploid species Coffea eugenioides and Coffea canephora) and the genome of diploid C. canephora. Sequence divergence was calculated on global alignments or on coding and non-coding sequences separately. A search for transposable elements detected 43 retrotransposons and 198 transposons in the sequences analyzed. Comparative insertion analysis made it possible to locate 165 TE insertions in the phylogenetic tree of the three genomes/subgenomes. In the tetraploid C. arabica, a homoeologous non-reciprocal transposition (HNRT) was detected and characterized: a 50 kb region of the C. eugenioides derived subgenome replaced the C. canephora derived counterpart. Comparative sequence analysis on three Coffea genomes/subgenomes revealed almost perfect gene synteny, low sequence divergence and a high number of shared transposable elements. Compared to the results of similar analysis in other genera (Aegilops/Triticum and Oryza), Coffea genomes/subgenomes appeared to be dramatically less diverged, which is consistent with the relatively recent radiation of the Coffea genus. Based on nucleotide substitution frequency, the HNRT was dated at 10,000-50,000 years BP, which is also the most recent estimation of the origin of C. arabica. PMID:22086332

  15. Inducing rye 1R chromosome structural changes in common wheat cv. Chinese spring by the gametocidal chromosome 2C of Aegilops cylindrica.

    PubMed

    Shi, Fang; Liu, Kun-Fan; Endo, Takashi R; Wang, Dao-Wen

    2005-05-01

    To generate 1 R deletion and translocation lines, we introduced a 2C chromosome,which was derived from Aegilops cylindrica and was known to have a gametocidal function when added monosomically into common wheat cv. Chinese Spring (CS) and its derivative, into a wheat-rye 1R chromosome disomic addition line (CS-1R"). When the individuals with chromosome constitution 21" + 1R" + 2C' (2n = 45) were selfed, the 1R chromosome structural changes were found to be induced with high frequency (24.1%) among the progenies. By using C-banding and GISH analysis, we analyzed 1R structural changes in 46 F3 individuals, which came from 23 F2 plants. The rearranged 1R chromosomes could be characterized in about 85% of the F3 individuals. This included telosome 1RL (39.1%), iso-chromosome 1 RL (2.2%), whole arm translocation involving 1RL (32.6%), telosome 1RS (4.3%), iso-chromosome 1RS (4.3%), and 1R deletion mutant with break point in the long arm (2.2%). The mutant 1R lines obtained in this study will potentially be useful in mapping the chromosome locations of agronomically important genes located in 1R. This study also demonstrated that molecular markers might be used to identify wheat chromosome arm involved in translocation with 1R. PMID:16018259

  16. New insights into the wheat chromosome 4D structure and virtual gene order, revealed by survey pyrosequencing

    PubMed Central

    Helguera, Marcelo; Rivarola, Máximo; Clavijo, Bernardo; Martis, Mihaela M.; Vanzetti, Leonardo S.; González, Sergio; Garbus, Ingrid; Leroy, Phillippe; Šimková, Hana; Valárik, Miroslav; Caccamo, Mario; Doležel, Jaroslav; Mayer, Klaus F.X.; Feuillet, Catherine; Tranquilli, Gabriela; Paniego, Norma; Echenique, Viviana

    2015-01-01

    Survey sequencing of the bread wheat (Triticum aestivum L.) genome (AABBDD) has been approached through different strategies delivering important information. However, the current wheat sequence knowledge is not complete. The aim of our study is to provide different and complementary set of data for chromosome 4D. A survey sequence was obtained by pyrosequencing of flow-sorted 4DS (7.2×) and 4DL (4.1×) arms. Single ends (SE) and long mate pairs (LMP) reads were assembled into contigs (223 Mb) and scaffolds (65 Mb) that were aligned to Aegilops tauschii draft genome (DD), anchoring 34 Mb to chromosome 4. Scaffolds annotation rendered 822 gene models. A virtual gene order comprising 1973 wheat orthologous gene loci and 381 wheat gene models was built. This order was largely consistent with the scaffold order determined based on a published high density map from the Ae. tauschii chromosome 4, using bin-mapped 4D ESTs as a common reference. The virtual order showed a higher collinearity with homeologous 4B compared to 4A. Additionally, a virtual map was constructed and ∼5700 genes (∼2200 on 4DS and ∼3500 on 4DL) predicted. The sequence and virtual order obtained here using the 454 platform were compared with the Illumina one used by the IWGSC, giving complementary information. PMID:25711827

  17. Electrophoretic survey of seedling esterases in wheats in relation to their phylogeny.

    PubMed

    Jaaska, V

    1980-11-01

    Evolutionary and ontogenetic variation of six seedling esterases of independent genetic control is studied in polyploid wheats and their diploid relatives by means of polyacrylamide gel electrophoresis. Four of them are shown to be controlled by homoeoallelic genes in chromosomes of third, sixth and seventh homoeologous groups.The isoesterase electrophoretic data are considered supporting a monophyletic origin of both the primitive tetraploid and the primitive hexaploid wheat from which contemporary taxa of polyploid wheats have emerged polyphyletically and polytopically through recurrent introgressive hybridization and accumulation of mutations. Ancestral diploids belonging or closely related to Triticum boeoticum, T. urartu, Aegilops speltoides and Ae. tauschii ssp. strangulata are genetically the most suitable genome donors of polyploid wheats. Diploids of the Emarginata subsection of the section Sitopsis, Aegilops longissima s.str., Ae. sharonensis, Ae. searsii and Ae. bicornis, are unsuitable for the role of the wheat B genome donors, being all fixed for the esterase B and D electromorphs different from those of tetraploid wheats. PMID:24305916

  18. Saturation Mapping of Hessian Fly Resistance Gene H26 in Synthetic Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hessian fly (Mayetiola destructor) resistance gene H26, derived from Aegilops tauschii, is one of the most effective R genes against various biotypes of Hessian fly. Using a limited number of PCR-based molecular markers, a previous study mapped H26 to the chromosomal deletion bin 3DL3-0.81-1.00. The...

  19. Molecular and genetic characterization of Hessian fly-resistance genes in synthetic hexaploid wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Synthetic hexaploid wheat (SHW), derived from crosses between tetraploid wheat (Triticum turgidum) and Aegilops tauschii, has proven to be an excellent source of resistance genes for various diseases and pests in wheat (T. aestivum). We previously evaluated a large collection of SHW lines for resis...

  20. Cloning and function validation of a nb-arc-lrr-type candidate gene for the greenbug aphid resistance locus, Gb3, in wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The greenbug, Schizaphis graminum, is one of the most important aphid pests of small grain crops in many parts of the world. A single dominant gene, Gb3 originated from Aegilops tauschii has shown consistent and durable resistance against prevailing greenbug biotypes in wheat fields. A fine genetic ...

  1. Molecular Mapping of Wheat Leaf Rust Resistance Gene Lr42

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leaf rust, caused by Puccinia triticina Eriks., is an important foliar disease of wheat (Triticum aestivum L.) worldwide. Leaf rust resistance gene Lr42 from Aegilops tauschii Coss. has been used as a source of rust resistance in breeding programs. To identify molecular markers closely linked to Lr4...

  2. A Candidate Gene for Aphid Resistance in Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The greenbug, Schizaphis graminum (Rondani), is an important aphid pest of small grain crops in many parts of the world. A single dominant gene, Gb3 originated from Aegilops tauschii has shown consistent and durable resistance against prevailing greenbug biotypes in wheat fields. Previously, we mapp...

  3. Evaluation and haplotype analysis of elite synthetic hexaploid wheat lines for resistance to Hessian fly

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Synthetic hexaploid wheat (SHW), derived from tetraploid wheat ' Aegilops tauschii hybrid, is an excellent source of resistance genes for various diseases and insects in wheat. The objectives of this study were to evaluate the elite SHW lines developed at the International Maize and Wheat Improvemen...

  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. Isolation, promoter analysis and expression profile of Dreb2 in response to drought stress in wheat ancestors.

    PubMed

    Tavakol, Elahe; Sardaro, Maria Luisa Savo; Shariati, J Vahid; Rossini, Laura; Porceddu, Enrico

    2014-10-01

    Drought is one of the most important abiotic stresses, constraining crop production seriously. The dehydration responsive element binding proteins (DREBs) are important plant-specific transcription factors that respond to various abiotic stresses and consequently induce abiotic stress-related genes that impart stress endurance in plants. Wild species are naturally exposed to various abiotic stresses and potentially harbor suitable alleles through natural selection. In this study we isolated and characterized Dreb2 from Triticum urartu (GenBank: KF731664), Aegilops speltoides (GenBank: KF731665) and Aegilops tauschii (GenBank: KF731663), the A, B and D genome ancestors of bread wheat, respectively. Analysis of over 1.3 kb upstream region of the gene revealed the presence of several conserved cis-acting regulatory elements including ABA-responsive elements, low temperature responsive elements, and several light and environmental signaling related motifs potentially vindicate Dreb2 responses to environmental signals. Moreover, the gene exhibited an alternative splicing, conserved among orthologous genes in grasses, and produced a non-functional isoform due to splicing in an exon resulted frame-shift creating an early stop codon before the functional domain. The expression analysis of Dreb2 under normal and different levels of dehydration stress conditions indicated that the two active spliced isoforms are upregulated when the plant exposed to drought stress whereas the non-functional isoform is downregulated in severe drought. PMID:25017054

  6. RNA-Seq Based Identification of Candidate Parasitism Genes of Cereal Cyst Nematode (Heterodera avenae) during Incompatible Infection to Aegilops variabilis.

    PubMed

    Zheng, Minghui; Long, Hai; Zhao, Yun; Li, Lin; Xu, Delin; Zhang, Haili; Liu, Feng; Deng, Guangbing; Pan, Zhifen; Yu, Maoqun

    2015-01-01

    One of the reasons for the progressive yield decline observed in cereals production is the rapid build-up of populations of the cereal cyst nematode (CCN, Heterodera avenae). These nematodes secrete so-call effectors into their host plant to suppress the plant defense responses, alter plant signaling pathways and then induce the formation of syncytium after infection. However, little is known about its molecular mechanism and parasitism during incompatible infection. To gain insight into its repertoire of parasitism genes, we investigated the transcriptome of the early parasitic second-stage (30 hours, 3 days and 9 days post infection) juveniles of the CCN as well as the CCN infected tissue of the host Aegilops variabilis by Illumina sequencing. Among all assembled unigenes, 681 putative genes of parasitic nematode were found, in which 56 putative effectors were identified, including novel pioneer genes and genes corresponding to previously reported effectors. All the 681 CCN unigenes were mapped to 229 GO terms and 200 KEGG pathways, including growth, development and several stimulus-related signaling pathways. Sixteen clusters were involved in the CCN unigene expression atlas at the early stages during infection process, and three of which were significantly gene-enriched. Besides, the protein-protein interaction network analysis revealed 35 node unigenes which may play an important role in the plant-CCN interaction. Moreover, in a comparison of differentially expressed genes between the pre-parasitic juveniles and the early parasitic juveniles, we found that hydrolase activity was up-regulated in pre J2s whereas binding activity was upregulated in infective J2s. RT-qPCR analysis on some selected genes showed detectable expression, indicating possible secretion of the proteins and putative role in infection. This study provided better insights into the incompatible interaction between H. avenae and the host plant Ae. varabilis. Moreover, RNAi targets with

  7. RNA-Seq Based Identification of Candidate Parasitism Genes of Cereal Cyst Nematode (Heterodera avenae) during Incompatible Infection to Aegilops variabilis

    PubMed Central

    Zheng, Minghui; Long, Hai; Zhao, Yun; Li, Lin; Xu, Delin; Zhang, Haili; Liu, Feng; Deng, Guangbing; Pan, Zhifen; Yu, Maoqun

    2015-01-01

    One of the reasons for the progressive yield decline observed in cereals production is the rapid build-up of populations of the cereal cyst nematode (CCN, Heterodera avenae). These nematodes secrete so-call effectors into their host plant to suppress the plant defense responses, alter plant signaling pathways and then induce the formation of syncytium after infection. However, little is known about its molecular mechanism and parasitism during incompatible infection. To gain insight into its repertoire of parasitism genes, we investigated the transcriptome of the early parasitic second-stage (30 hours, 3 days and 9 days post infection) juveniles of the CCN as well as the CCN infected tissue of the host Aegilops variabilis by Illumina sequencing. Among all assembled unigenes, 681 putative genes of parasitic nematode were found, in which 56 putative effectors were identified, including novel pioneer genes and genes corresponding to previously reported effectors. All the 681 CCN unigenes were mapped to 229 GO terms and 200 KEGG pathways, including growth, development and several stimulus-related signaling pathways. Sixteen clusters were involved in the CCN unigene expression atlas at the early stages during infection process, and three of which were significantly gene-enriched. Besides, the protein-protein interaction network analysis revealed 35 node unigenes which may play an important role in the plant-CCN interaction. Moreover, in a comparison of differentially expressed genes between the pre-parasitic juveniles and the early parasitic juveniles, we found that hydrolase activity was up-regulated in pre J2s whereas binding activity was upregulated in infective J2s. RT-qPCR analysis on some selected genes showed detectable expression, indicating possible secretion of the proteins and putative role in infection. This study provided better insights into the incompatible interaction between H. avenae and the host plant Ae. varabilis. Moreover, RNAi targets with

  8. Molecular evolution and nucleotide diversity of nuclear plastid phosphoglycerate kinase (PGK) gene in Triticeae (Poaceae).

    PubMed

    Adderley, Shawn; Sun, Genlou

    2014-01-01

    Levels of nucleotide divergence provide key evidence in the evolution of polyploids. The nucleotide diversity of 226 sequences of pgk1 gene in Triticeae species was characterized. Phylogenetic analyses based on the pgk1 gene were carried out to determine the diploid origin of polyploids within the tribe in relation to their A(u), B, D, St, Ns, P, and H haplomes. Sequences from the Ns genome represented the highest nucleotide diversity values for both polyploid and diploid species with π=0.03343 and θ=0.03536 for polyploid Ns genome sequences and π=0.03886 and θ=0.03886 for diploid Psathyrostachys sequences, while Triticum urartu represented the lowest diversity among diploid species at π=0.0011 and θ=0.0011. Nucleotide variation of diploid Aegilops speltoides (π=0.2441, presumed the B genome donor of Triticum species) is five times higher than that (π=0.00483) of B genome in polyploid species. Significant negative Tajima's D values for the St, A(u), and D genomes along with high rates of polymorphisms and low sequence diversity were observed. Origins of the A(u), B, and D genomes were linked to T. urartu, A. speltoides, and A. tauschii, respectively. Putative St genome donor was Pseudoroegneria, while Ns and P donors were Psathyrostachys and Agropyron. H genome diploid donor is Hordeum. PMID:24120623

  9. 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

  10. 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

  11. PCR-based analysis of the intergenic spacers of the Nor loci on the A genomes of Triticum diploids and polyploids.

    PubMed

    Sallares, R; Brown, T A

    1999-02-01

    We present DNA sequence data showing population variation in the intergenic spacer (IGS) regions of the ribosomal DNAs (rDNAs) on the A genomes of 27 diploid and polyploid wheats. PCRs (polymerase chain reactions) specific for the A(m) genome gave products with five populations of Triticum monococcum but did not give products with AABB or AABBDD wheats. PCRs specific to the A(u) genome of T. urartu gave products with all the AABB and AABBDD polyploids that were tested, but not with T. monococcum. AAGG tetraploids gave products only with the A(u)-specific primers, but the AAAAGG hexaploid T. zhukovskyi gave products with both the A(u) and A(m) primers. Phylogenetic analysis showed a substantial degree of IGS divergence for both the A(m) and A(u) genomes in diploids and polyploids compared with other genomes of Triticum and Aegilops. The rate of evolution of the IGS is much greater than previously reported for the internal transcribed region of the rDNAs but the view that the IGS only gives random noise is rejected, the IGS sequences presented here reflecting the general evolutionary trends affecting the wheat genome as a whole. PMID:10208005

  12. Comparative genome analysis between Agrostis stolonifera and members of the Pooideae subfamily, including Brachypodium distachyon.

    PubMed

    Araneda, Loreto; Sim, Sung-Chur; Bae, Jin-Joo; Chakraborty, Nanda; Curley, Joe; Chang, Taehyun; Inoue, Maiko; Warnke, Scott; Jung, Geunhwa

    2013-01-01

    Creeping bentgrass (Agrostis stolonifera, allotetraploid 2n = 4x = 28) is one of the major cool-season turfgrasses. It is widely used on golf courses due to its tolerance to low mowing and aggressive growth habit. In this study, we investigated genome relationships of creeping bentgrass relative to the Triticeae (a consensus map of Triticum aestivum, T. tauschii, Hordeum vulgare, and H. spontaneum), oat, rice, and ryegrass maps using a common set of 229 EST-RFLP markers. The genome comparisons based on the RFLP markers revealed large-scale chromosomal rearrangements on different numbers of linkage groups (LGs) of creeping bentgrass relative to the Triticeae (3 LGs), oat (4 LGs), and rice (8 LGs). However, we detected no chromosomal rearrangement between creeping bentgrass and ryegrass, suggesting that these recently domesticated species might be closely related, despite their memberships to different Pooideae tribes. In addition, the genome of creeping bentgrass was compared with the complete genome sequence of Brachypodium distachyon in Pooideae subfamily using both sequences of the above-mentioned mapped EST-RFLP markers and sequences of 8,470 publicly available A. stolonifera ESTs (AgEST). We discovered large-scale chromosomal rearrangements on six LGs of creeping bentgrass relative to B. distachyon. Also, a total of 24 syntenic blocks based on 678 orthologus loci were identified between these two grass species. The EST orthologs can be utilized in further comparative mapping of Pooideae species. These results will be useful for genetic improvement of Agrostis species and will provide a better understanding of evolution within Pooideae species. PMID:24244501

  13. Genome walking.

    PubMed

    Shapter, Frances M; Waters, Daniel L E

    2014-01-01

    Genome walking is a method for determining the DNA sequence of unknown genomic regions flanking a region of known DNA sequence. The Genome walking has the potential to capture 6-7 kb of sequence in a single round. Ideal for identifying gene promoter regions where only the coding region. Genome walking also has significant utility for capturing homologous genes in new species when there are areas in the target gene with strong sequence conservation to the characterized species. The increasing use of next-generation sequencing technologies will see the principles of genome walking adapted to in silico methods. However, for smaller projects, PCR-based genome walking will remain an efficient method of characterizing unknown flanking sequence. PMID:24243201

  14. 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

  15. Prophage Genomics

    PubMed Central

    Canchaya, Carlos; Proux, Caroline; Fournous, Ghislain; Bruttin, Anne; Brüssow, Harald

    2003-01-01

    The majority of the bacterial genome sequences deposited in the National Center for Biotechnology Information database contain prophage sequences. Analysis of the prophages suggested that after being integrated into bacterial genomes, they undergo a complex decay process consisting of inactivating point mutations, genome rearrangements, modular exchanges, invasion by further mobile DNA elements, and massive DNA deletion. We review the technical difficulties in defining such altered prophage sequences in bacterial genomes and discuss theoretical frameworks for the phage-bacterium interaction at the genomic level. The published genome sequences from three groups of eubacteria (low- and high-G+C gram-positive bacteria and γ-proteobacteria) were screened for prophage sequences. The prophages from Streptococcus pyogenes served as test case for theoretical predictions of the role of prophages in the evolution of pathogenic bacteria. The genomes from further human, animal, and plant pathogens, as well as commensal and free-living bacteria, were included in the analysis to see whether the same principles of prophage genomics apply for bacteria living in different ecological niches and coming from distinct phylogenetical affinities. The effect of selection pressure on the host bacterium is apparently an important force shaping the prophage genomes in low-G+C gram-positive bacteria and γ-proteobacteria. PMID:12794192

  16. OrthoVenn: a web server for genome wide comparison and annotation of orthologous clusters across multiple species.

    PubMed

    Wang, Yi; Coleman-Derr, Devin; Chen, Guoping; Gu, Yong Q

    2015-07-01

    Genome wide analysis of orthologous clusters is an important component of comparative genomics studies. Identifying the overlap among orthologous clusters can enable us to elucidate the function and evolution of proteins across multiple species. Here, we report a web platform named OrthoVenn that is useful for genome wide comparisons and visualization of orthologous clusters. OrthoVenn provides coverage of vertebrates, metazoa, protists, fungi, plants and bacteria for the comparison of orthologous clusters and also supports uploading of customized protein sequences from user-defined species. An interactive Venn diagram, summary counts, and functional summaries of the disjunction and intersection of clusters shared between species are displayed as part of the OrthoVenn result. OrthoVenn also includes in-depth views of the clusters using various sequence analysis tools. Furthermore, OrthoVenn identifies orthologous clusters of single copy genes and allows for a customized search of clusters of specific genes through key words or BLAST. OrthoVenn is an efficient and user-friendly web server freely accessible at http://probes.pw.usda.gov/OrthoVenn or http://aegilops.wheat.ucdavis.edu/OrthoVenn. PMID:25964301

  17. Aquaculture Genomics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The genomics chapter covers the basics of genome mapping and sequencing and the current status of several relevant species. The chapter briefly describes the development and use of (cDNA, BAC, etc.) libraries for mapping and obtaining specific sequence information. Other topics include comparative ...

  18. Antarctic Genomics

    PubMed Central

    Clarke, Andrew; Cockell, Charles S.; Convey, Peter; Detrich III, H. William; Fraser, Keiron P. P.; Johnston, Ian A.; Methe, Barbara A.; Murray, Alison E.; Peck, Lloyd S.; Römisch, Karin; Rogers, Alex D.

    2004-01-01

    With the development of genomic science and its battery of technologies, polar biology stands on the threshold of a revolution, one that will enable the investigation of important questions of unprecedented scope and with extraordinary depth and precision. The exotic organisms of polar ecosystems are ideal candidates for genomic analysis. Through such analyses, it will be possible to learn not only the novel features that enable polar organisms to survive, and indeed thrive, in their extreme environments, but also fundamental biological principles that are common to most, if not all, organisms. This article aims to review recent developments in Antarctic genomics and to demonstrate the global context of such studies. PMID:18629155

  19. The Molecular Basis of Genetic Diversity among Cytoplasms of TRITICUM and AEGILOPS Species. II. on the Origin of Polyploid Wheat Cytoplasms as Suggested by Chloroplast DNA Restriction Fragment Patterns.

    PubMed

    Tsunewaki, K; Ogihara, Y

    1983-05-01

    In attempts to identify the phylogenetic donors of cytoplasm to Emmer-Dinkel and Timopheevi groups of wheat (Triticum), and the Aegilops kotschyi-Ae. variabilis complex, the restriction fragment patterns of chloroplast DNAs of representative species were compared with those of their putative diploid ancestors. The following seven restriction enzymes were used; BamHI, EcoRI, HindIII, KpnI, PstI, SmaI and XhoI. The restriction fragment patterns of an Emmer and a Dinkel (common) wheat were identical with those of Ae. longissima , and different from those of Ae. aucheri, Ae. bicornis, Ae. searsii, Ae. sharonensis, Ae. speltoides, and T. urartu by 4 to 12 fragments. The restriction fragment patterns of a Timopheevi wheat were identical with those of Ae. aucheri, and different from those of all other diploids by four to nine fragments. The restriction fragment patterns of Ae. variabilis were identical to those of Ae. bicornis and Ae. searsii , and different from those of all other species. Thus, we have concluded that Ae. longissima, Ae. aucheri and Ae. bicornis (or Ae. searsii) were the cytoplasm donors to the Emmer-Dinkel and the Timopheevi groups, and the Ae. kotschyi-Ae. variabilis complex, respectively. A diphyletic origin of Emmer and Timopheevi groups is supported by the present results. PMID:17246126

  20. Genomic Testing

    MedlinePlus

    ... Working Group Independent Web site Informing the effective integration of genomics into health practice—Lynch syndrome ACCE Model for Evaluating Genetic Tests Recommendations by the EGAPP Working Group Top of ... ...

  1. Sequence elimination and cytosine methylation are rapid and reproducible responses of the genome to wide hybridization and allopolyploidy in wheat.

    PubMed

    Shaked, H; Kashkush, K; Ozkan, H; Feldman, M; Levy, A A

    2001-08-01

    Interspecific or intergeneric hybridization, followed by chromosome doubling, can lead to the formation of new allopolyploid species. Recent studies indicate that allopolyploid formation is associated with genetic and epigenetic changes, although little is known about the type of changes that occur, how rapidly they occur, and the type of sequences involved. To address these matters, we have surveyed F1 hybrids between diploid species from the wheat (Aegilops and Triticum) group and their derived allotetraploids by screening a large number of loci using amplified fragment length polymorphism and DNA gel blot analysis and by assaying the extent of cytosine methylation. We found that sequence elimination is one of the major and immediate responses of the wheat genome to wide hybridization or allopolyploidy, that it affects a large fraction of the genome, and that it is reproducible. In one cross between AE: sharonensis x AE: umbellulata, 14% of the loci from AE: sharonensis were eliminated compared with only 0.5% from AE: umbellulata, with most changes occurring in the F1 hybrid. In contrast, crosses between AE: longissima x T. urartu showed that sequence elimination was more frequent after chromosome doubling. Alterations in cytosine methylation occurred in approximately 13% of the loci, either in the F1 hybrid or in the allopolyploid. For eight of nine bands that were isolated, the sequences that underwent elimination corresponded to low-copy DNA, whereas alterations in methylation patterns affected both repetitive DNA sequences, such as retrotransposons, and low-copy DNA in approximately equal proportions. PMID:11487690

  2. Genome databases

    SciTech Connect

    Courteau, J.

    1991-10-11

    Since the Genome Project began several years ago, a plethora of databases have been developed or are in the works. They range from the massive Genome Data Base at Johns Hopkins University, the central repository of all gene mapping information, to small databases focusing on single chromosomes or organisms. Some are publicly available, others are essentially private electronic lab notebooks. Still others limit access to a consortium of researchers working on, say, a single human chromosome. An increasing number incorporate sophisticated search and analytical software, while others operate as little more than data lists. In consultation with numerous experts in the field, a list has been compiled of some key genome-related databases. The list was not limited to map and sequence databases but also included the tools investigators use to interpret and elucidate genetic data, such as protein sequence and protein structure databases. Because a major goal of the Genome Project is to map and sequence the genomes of several experimental animals, including E. coli, yeast, fruit fly, nematode, and mouse, the available databases for those organisms are listed as well. The author also includes several databases that are still under development - including some ambitious efforts that go beyond data compilation to create what are being called electronic research communities, enabling many users, rather than just one or a few curators, to add or edit the data and tag it as raw or confirmed.

  3. Listeria Genomics

    NASA Astrophysics Data System (ADS)

    Cabanes, Didier; Sousa, Sandra; Cossart, Pascale

    The opportunistic intracellular foodborne pathogen Listeria monocytogenes has become a paradigm for the study of host-pathogen interactions and bacterial adaptation to mammalian hosts. Analysis of L. monocytogenes infection has provided considerable insight into how bacteria invade cells, move intracellularly, and disseminate in tissues, as well as tools to address fundamental processes in cell biology. Moreover, the vast amount of knowledge that has been gathered through in-depth comparative genomic analyses and in vivo studies makes L. monocytogenes one of the most well-studied bacterial pathogens. This chapter provides an overview of progress in the exploration of genomic, transcriptomic, and proteomic data in Listeria spp. to understand genome evolution and diversity, as well as physiological aspects of metabolism used by bacteria when growing in diverse environments, in particular in infected hosts.

  4. Genome Informatics

    PubMed Central

    Winslow, Raimond L.; Boguski, Mark S.

    2005-01-01

    This article reviews recent advances in genomics and informatics relevant to cardiovascular research. In particular, we review the status of (1) whole genome sequencing efforts in human, mouse, rat, zebrafish, and dog; (2) the development of data mining and analysis tools; (3) the launching of the National Heart, Lung, and Blood Institute Programs for Genomics Applications and Proteomics Initiative; (4) efforts to characterize the cardiac transcriptome and proteome; and (5) the current status of computational modeling of the cardiac myocyte. In each instance, we provide links to relevant sources of information on the World Wide Web and critical appraisals of the promises and the challenges of an expanding and diverse information landscape. PMID:12750305

  5. Whither genomics?

    PubMed Central

    Murray, Andrew W

    2000-01-01

    The flood of data from genome-wide analysis is transforming biology. We need to develop new, interdisciplinary approaches to convert these data into information about the components and structures of individual biological pathways and to use the resulting information to yield knowledge about general principles that explain the functions and evolution of life. PMID:11104516

  6. 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

  7. 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

  8. Extensive Pericentric Rearrangements in the Bread Wheat (Triticum aestivum L.) Genotype “Chinese Spring” Revealed from Chromosome Shotgun Sequence Data

    PubMed Central

    Ma, Jian; Stiller, Jiri; Wei, Yuming; Zheng, You-Liang; Devos, Katrien M.; Doležel, Jaroslav; Liu, Chunji

    2014-01-01

    The bread wheat (Triticum aestivum L.) genotype “Chinese Spring” (“CS”) is the reference base in wheat genetics and genomics. Pericentric rearrangements in this genotype were systematically assessed by analyzing homoeoloci for a set of nonredundant genes from Brachypodium distachyon, Triticum urartu, and Aegilops tauschii in the CS chromosome shotgun sequence obtained from individual chromosome arms flow-sorted from CS aneuploid lines. Based on patterns of their homoeologous arm locations, 551 genes indicated the presence of pericentric inversions in at least 10 of the 21 chromosomes. Available data from deletion bin-mapped expressed sequence tags and genetic mapping in wheat indicated that all inversions had breakpoints in the low-recombinant gene-poor pericentromeric regions. The large number of putative intrachromosomal rearrangements suggests the presence of extensive structural differences among the three subgenomes, at least some of which likely occurred during the production of the aneuploid lines of this hexaploid wheat genotype. These differences could have significant implications in wheat genome research where comparative approaches are used such as in ordering and orientating sequence contigs and in gene cloning. PMID:25349265

  9. Polyphenol oxidase (PPO) in wheat and wild relatives: molecular evidence for a multigene family.

    PubMed

    Massa, Alicia N; Beecher, Brian; Morris, Craig F

    2007-05-01

    Wheat polyphenol oxidase (PPO) is the major cause of browning reactions that discolor Asian noodles and other wheat products. It has been hypothesized that genes encoding wheat PPOs may have evolved by gene duplication into a multigene family. Here we characterized PPO genomic sequences from diploid (Triticum monococcum, T. urartu, Aegilops tauschii, and Ae. speltoides), tetraploid (T. turgidum, subspecies dicoccoides and durum) and hexaploid (T. aestivum cultivars Klasic and ID377s) wheat species to gain a better understanding of the structure and organization of PPO genes. DNA fragments were amplified from a highly polymorphic and phylogenetic informative region of the gene. As a result, we obtained highly discriminative sequences. Three distinct PPOs, obtained from the A genome of T. monococcum, provided evidence for gene duplication events (paralogous loci). Furthermore, the number of sequences obtained for bread and durum wheat was higher than the expected number of orthologous loci. Sequence comparison revealed nucleotide and structural diversity, and detected five sequence intron types, all with a common insertion position. This was hypothesized to be homologous to that of intron 2 of previously reported wheat PPOs. A MITE of the Stowaway family accounted for the major difference between the five intervening sequences, and was unique to T. aestivum cv. Klasic. Nucleotide and structural diversity, together with well-resolved phylogenetic trees, provided molecular evidence to support the hypothesis of a PPO multigene family structure and organization. PMID:17468807

  10. High Transferability of Homoeolog-Specific Markers between Bread Wheat and Newly Synthesized Hexaploid Wheat Lines.

    PubMed

    Zeng, Deying; Luo, Jiangtao; Li, Zenglin; Chen, Gang; Zhang, Lianquan; Ning, Shunzong; Yuan, Zhongwei; Zheng, Youliang; Hao, Ming; Liu, Dengcai

    2016-01-01

    Bread wheat (Triticum aestivum, 2n = 6x = 42, AABBDD) has a complex allohexaploid genome, which makes it difficult to differentiate between the homoeologous sequences and assign them to the chromosome A, B, or D subgenomes. The chromosome-based draft genome sequence of the 'Chinese Spring' common wheat cultivar enables the large-scale development of polymerase chain reaction (PCR)-based markers specific for homoeologs. Based on high-confidence 'Chinese Spring' genes with known functions, we developed 183 putative homoeolog-specific markers for chromosomes 4B and 7B. These markers were used in PCR assays for the 4B and 7B nullisomes and their euploid synthetic hexaploid wheat (SHW) line that was newly generated from a hybridization between Triticum turgidum (AABB) and the wild diploid species Aegilops tauschii (DD). Up to 64% of the markers for chromosomes 4B or 7B in the SHW background were confirmed to be homoeolog-specific. Thus, these markers were highly transferable between the 'Chinese Spring' bread wheat and SHW lines. Homoeolog-specific markers designed using genes with known functions may be useful for genetic investigations involving homoeologous chromosome tracking and homoeolog expression and interaction analyses. PMID:27611704

  11. 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

  12. Citrus Genomics

    PubMed Central

    Talon, Manuel; Gmitter Jr., Fred G.

    2008-01-01

    Citrus is one of the most widespread fruit crops globally, with great economic and health value. It is among the most difficult plants to improve through traditional breeding approaches. Currently, there is risk of devastation by diseases threatening to limit production and future availability to the human population. As technologies rapidly advance in genomic science, they are quickly adapted to address the biological challenges of the citrus plant system and the world's industries. The historical developments of linkage mapping, markers and breeding, EST projects, physical mapping, an international citrus genome sequencing project, and critical functional analysis are described. Despite the challenges of working with citrus, there has been substantial progress. Citrus researchers engaged in international collaborations provide optimism about future productivity and contributions to the benefit of citrus industries worldwide and to the human population who can rely on future widespread availability of this health-promoting and aesthetically pleasing fruit crop. PMID:18509486

  13. Ancient genomics

    PubMed Central

    Der Sarkissian, Clio; Allentoft, Morten E.; Ávila-Arcos, María C.; Barnett, Ross; Campos, Paula F.; Cappellini, Enrico; Ermini, Luca; Fernández, Ruth; da Fonseca, Rute; Ginolhac, Aurélien; Hansen, Anders J.; Jónsson, Hákon; Korneliussen, Thorfinn; Margaryan, Ashot; Martin, Michael D.; Moreno-Mayar, J. Víctor; Raghavan, Maanasa; Rasmussen, Morten; Velasco, Marcela Sandoval; Schroeder, Hannes; Schubert, Mikkel; Seguin-Orlando, Andaine; Wales, Nathan; Gilbert, M. Thomas P.; Willerslev, Eske; Orlando, Ludovic

    2015-01-01

    The past decade has witnessed a revolution in ancient DNA (aDNA) research. Although the field's focus was previously limited to mitochondrial DNA and a few nuclear markers, whole genome sequences from the deep past can now be retrieved. This breakthrough is tightly connected to the massive sequence throughput of next generation sequencing platforms and the ability to target short and degraded DNA molecules. Many ancient specimens previously unsuitable for DNA analyses because of extensive degradation can now successfully be used as source materials. Additionally, the analytical power obtained by increasing the number of sequence reads to billions effectively means that contamination issues that have haunted aDNA research for decades, particularly in human studies, can now be efficiently and confidently quantified. At present, whole genomes have been sequenced from ancient anatomically modern humans, archaic hominins, ancient pathogens and megafaunal species. Those have revealed important functional and phenotypic information, as well as unexpected adaptation, migration and admixture patterns. As such, the field of aDNA has entered the new era of genomics and has provided valuable information when testing specific hypotheses related to the past. PMID:25487338

  14. Genomic Imprinting

    PubMed Central

    Bajrami, Emirjeta; Spiroski, Mirko

    2016-01-01

    BACKGROUND: Genomic imprinting is the inheritance out of Mendelian borders. Many of inherited diseases and human development violates Mendelian law of inheritance, this way of inheriting is studied by epigenetics. AIM: The aim of this review is to analyze current opinions and options regarding to this way of inheriting. RESULTS: Epigenetics shows that gene expression undergoes changes more complex than modifications in the DNA sequence; it includes the environmental influence on the gametes before conception. Humans inherit two alleles from mother and father, both are functional for the majority of the genes, but sometimes one is turned off or “stamped” and doesn’t show in offspring, that gene is imprinted. Imprinting means that that gene is silenced, and gene from other parent is expressed. The mechanisms for imprinting are still incompletely defined, but they involve epigenetic modifications that are erased and then reset during the creation of eggs and sperm. Genomic imprinting is a process of silencing genes through DNA methylation. The repressed allele is methylated, while the active allele is unmethylated. The most well-known conditions include Prader-Willi syndrome, and Angelman syndrome. Both of these syndromes can be caused by imprinting or other errors involving genes on the long arm of chromosome 15. CONCLUSIONS: Genomic imprinting and other epigenetic mechanisms such as environment is shown that plays role in offspring neurodevelopment and autism spectrum disorder. PMID:27275355

  15. Generation of Wheat Transcription Factor FOX Rice Lines and Systematic Screening for Salt and Osmotic Stress Tolerance

    PubMed Central

    Zhang, Qian; Liu, Yayun; Zhu, Butuo; Cao, Jian; Li, Zhanpeng; Han, Longzhi; Jia, Jizeng; Zhao, Guangyao; Sun, Xuehui

    2015-01-01

    Transcription factors (TFs) play important roles in plant growth, development, and responses to environmental stress. In this study, we collected 1,455 full-length (FL) cDNAs of TFs, representing 45 families, from wheat and its relatives Triticum urartu, Aegilops speltoides, Aegilops tauschii, Triticum carthlicum, and Triticum aestivum. More than 15,000 T0 TF FOX (Full-length cDNA Over-eXpressing) rice lines were generated; of these, 10,496 lines set seeds. About 14.88% of the T0 plants showed obvious phenotypic changes. T1 lines (5,232 lines) were screened for salt and osmotic stress tolerance using 150 mM NaCl and 20% (v/v) PEG-4000, respectively. Among them, five lines (591, 746, 1647, 1812, and J4065) showed enhanced salt stress tolerance, five lines (591, 746, 898, 1078, and 1647) showed enhanced osmotic stress tolerance, and three lines (591, 746, and 1647) showed both salt and osmotic stress tolerance. Further analysis of the T-DNA flanking sequences showed that line 746 over-expressed TaEREB1, line 898 over-expressed TabZIPD, and lines 1812 and J4065 over-expressed TaOBF1a and TaOBF1b, respectively. The enhanced salt and osmotic stress tolerance of lines 898 and 1812 was confirmed by retransformation of the respective genes. Our results demonstrate that a heterologous FOX system may be used as an alternative genetic resource for the systematic functional analysis of the wheat genome. PMID:26176782

  16. Genomes on ice.

    PubMed

    Parkhill, Julian

    2016-03-01

    This month's Genome Watch discusses the analysis of a Helicobacter pylori genome from the preserved Copper-Age mummy known as the Iceman and how ancient genomes shed light on the history of bacterial pathogens. PMID:26853114

  17. Whole Genome Sequencing

    MedlinePlus

    ... you want to learn. Search form Search Whole Genome Sequencing You are here Home Testing & Services Testing ... the full story, click here . What is whole genome sequencing? Whole genome sequencing is the mapping out ...

  18. Ensembl Genomes 2016: more genomes, more complexity.

    PubMed

    Kersey, Paul Julian; Allen, James E; Armean, Irina; Boddu, Sanjay; Bolt, Bruce J; Carvalho-Silva, Denise; Christensen, Mikkel; Davis, Paul; Falin, Lee J; Grabmueller, Christoph; Humphrey, Jay; Kerhornou, Arnaud; Khobova, Julia; Aranganathan, Naveen K; Langridge, Nicholas; Lowy, Ernesto; McDowall, Mark D; Maheswari, Uma; Nuhn, Michael; Ong, Chuang Kee; Overduin, Bert; Paulini, Michael; Pedro, Helder; Perry, Emily; Spudich, Giulietta; Tapanari, Electra; Walts, Brandon; Williams, Gareth; Tello-Ruiz, Marcela; Stein, Joshua; Wei, Sharon; Ware, Doreen; Bolser, Daniel M; Howe, Kevin L; Kulesha, Eugene; Lawson, Daniel; Maslen, Gareth; Staines, Daniel M

    2016-01-01

    Ensembl Genomes (http://www.ensemblgenomes.org) is an integrating resource for genome-scale data from non-vertebrate species, complementing the resources for vertebrate genomics developed in the context of the Ensembl project (http://www.ensembl.org). Together, the two resources provide a consistent set of programmatic and interactive interfaces to a rich range of data including reference sequence, gene models, transcriptional data, genetic variation and comparative analysis. This paper provides an update to the previous publications about the resource, with a focus on recent developments. These include the development of new analyses and views to represent polyploid genomes (of which bread wheat is the primary exemplar); and the continued up-scaling of the resource, which now includes over 23 000 bacterial genomes, 400 fungal genomes and 100 protist genomes, in addition to 55 genomes from invertebrate metazoa and 39 genomes from plants. This dramatic increase in the number of included genomes is one part of a broader effort to automate the integration of archival data (genome sequence, but also associated RNA sequence data and variant calls) within the context of reference genomes and make it available through the Ensembl user interfaces. PMID:26578574

  19. Ensembl genomes 2016: more genomes, more complexity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ensembl Genomes (http://www.ensemblgenomes.org) is an integrating resource for genome-scale data from non-vertebrate species, complementing the resources for vertebrate genomics developed in the context of the Ensembl project (http://www.ensembl.org). Together, the two resources provide a consistent...

  20. Ensembl Genomes 2016: more genomes, more complexity

    PubMed Central

    Kersey, Paul Julian; Allen, James E.; Armean, Irina; Boddu, Sanjay; Bolt, Bruce J.; Carvalho-Silva, Denise; Christensen, Mikkel; Davis, Paul; Falin, Lee J.; Grabmueller, Christoph; Humphrey, Jay; Kerhornou, Arnaud; Khobova, Julia; Aranganathan, Naveen K.; Langridge, Nicholas; Lowy, Ernesto; McDowall, Mark D.; Maheswari, Uma; Nuhn, Michael; Ong, Chuang Kee; Overduin, Bert; Paulini, Michael; Pedro, Helder; Perry, Emily; Spudich, Giulietta; Tapanari, Electra; Walts, Brandon; Williams, Gareth; Tello–Ruiz, Marcela; Stein, Joshua; Wei, Sharon; Ware, Doreen; Bolser, Daniel M.; Howe, Kevin L.; Kulesha, Eugene; Lawson, Daniel; Maslen, Gareth; Staines, Daniel M.

    2016-01-01

    Ensembl Genomes (http://www.ensemblgenomes.org) is an integrating resource for genome-scale data from non-vertebrate species, complementing the resources for vertebrate genomics developed in the context of the Ensembl project (http://www.ensembl.org). Together, the two resources provide a consistent set of programmatic and interactive interfaces to a rich range of data including reference sequence, gene models, transcriptional data, genetic variation and comparative analysis. This paper provides an update to the previous publications about the resource, with a focus on recent developments. These include the development of new analyses and views to represent polyploid genomes (of which bread wheat is the primary exemplar); and the continued up-scaling of the resource, which now includes over 23 000 bacterial genomes, 400 fungal genomes and 100 protist genomes, in addition to 55 genomes from invertebrate metazoa and 39 genomes from plants. This dramatic increase in the number of included genomes is one part of a broader effort to automate the integration of archival data (genome sequence, but also associated RNA sequence data and variant calls) within the context of reference genomes and make it available through the Ensembl user interfaces. PMID:26578574

  1. Microsatellite Mutation Rate during Allohexaploidization of Newly Resynthesized Wheat

    PubMed Central

    Luo, Jiangtao; Hao, Ming; Zhang, Li; Chen, Jixiang; Zhang, Lianquan; Yuan, Zhongwei; Yan, Zehong; Zheng, Youliang; Zhang, Huaigang; Yen, Yang; Liu, Dengcai

    2012-01-01

    Simple sequence repeats (SSRs, also known as microsatellites) are known to be mutational hotspots in genomes. DNA rearrangements have also been reported to accompany allopolyploidization. A study of the effect of allopolyploidization on SSR mutation is therefore important for understanding the origin and evolutionary dynamics of SSRs in allopolyploids. Three synthesized double haploid (SynDH) populations were made from 241 interspecific F1 haploid hybrids between Triticum turgidum L. and Aegilops tauschii (Coss.) through spontaneous chromosome doubling via unreduced gametes. Mutation events were studied at 160 SSR loci in the S1 generation (the first generation after chromosome doubling) of the three SynDH populations. Of the 148260 SSR alleles investigated in S1 generation, only one mutation (changed number of repeats) was confirmed with a mutation rate of 6.74 × 10−6. This mutation most likely occurred in the respective F1 hybrid. In comparison with previously reported data, our results suggested that allohexaploidization of wheat did not increase SSR mutation rate. PMID:23202911

  2. Development, identification and utilization of introgression lines using Chinese endemic and synthetic wheat as donors.

    PubMed

    Gu, Liqing; Wei, Bo; Fan, Renchun; Jia, Xu; Wang, Xianping; Zhang, Xiangqi

    2015-08-01

    Chromosome segmental introgression lines (ILs) are an effective way to utilize germplasm resources in crops. To improve agronomic traits of wheat cultivar (Triticum aestivum) Shi 4185, four sets of ILs were developed. The donors were Chinese endemic subspecies accessions Yunnan wheat (T. aestivum ssp. yunnanense) YN3, Tibetan semi-wild wheat (T. aestivum ssp. tibetanum) XZ-ZM19450, and Xinjiang wheat (T. aestivum ssp. petropavlovskyi) XJ5, and synthetic wheat HC-XM1620 derived from a cross between T. durum acc. D67.2/P66.270 with Aegilops tauschii acc. 218. Totals of 356, 366, 445 and 457 simple sequence repeat (SSR) markers were polymorphic between Shi 4185 and YN3, XZ-ZM19450, XJ5 and HC-XM1620, respectively. In total, 991 ILs were identified, including 300 derived from YN3, covering 95% of the genome of Shi 4185, 218 from XZ-ZM19450 (79%), 279 from XJ5 (97%), and 194 from HC-ZX1620 (84%). The sizes and locations of each introgression were determined from a consensus SSR linkage map. Using the ILs, 11 putative quantitative trait loci (QTLs) were identified for plant height (PH), spike length (SL) and grain number per spike (GNS). Comparative analyses of 24 elite ILs with the parents revealed that the four donor parents could be important resources to improve wheat SL and GNS. Our work offers a case for utilizing endemic landraces for QTL mapping and improvement of wheat cultivars using introgression lines. PMID:25545589

  3. A novel family of γ-gliadin genes are highly regulated by nitrogen supply in developing wheat grain

    PubMed Central

    Shewry, Peter R.

    2013-01-01

    Six wheat cultivars were grown at Rothamsted (UK) with three levels of nitrogen fertilizer (100, 200 and 350kg N/ha) in 2009 and 2010. Gene expression in developing caryopses at 21 days post-anthesis (DPA) was profiled using the Affymetrix Wheat GeneChip®. Four of 105 transcripts which were significantly upregulated by nitrogen level were annotated as γ-3 hordein and the identification of corresponding expressed sequence tags showed that they differed in sequence from previously described (typical) γ-gliadins and represented a novel form of γ-gliadin. Real-time reverse transcriptase PCR at 14, 21, 28 and 35 DPA revealed that this transcript was most abundant and most responsive to nitrogen at 21 DPA. Four novel γ-gliadin genes were isolated by PCR amplification from wheat cv. Hereward and the related species Aegilops tauschii and Triticum monococcum while three were assembled from the genomic sequence database of wheat cv. Chinese Spring (www.cerealsdb.uk.net). Comparison of the deduced amino acid sequences of the seven genes showed that they shared only 44.4–46.0% identity with the sequence of a typical γ-gliadin (accession number EF15018), but 61.8–68.3% identity with the sequence of γ-3 hordein from the wild barley species Hordeum chilense (AY338065). The novel γ-gliadin genes were localized to the group 1 chromosomes (1A, 1B, 1D). PMID:23162123

  4. Funding Opportunity: Genomic Data Centers

    Cancer.gov

    Funding Opportunity CCG, Funding Opportunity Center for Cancer Genomics, CCG, Center for Cancer Genomics, CCG RFA, Center for cancer genomics rfa, genomic data analysis network, genomic data analysis network centers,

  5. Enabling functional genomics with genome engineering

    PubMed Central

    Hilton, Isaac B.; Gersbach, Charles A.

    2015-01-01

    Advances in genome engineering technologies have made the precise control over genome sequence and regulation possible across a variety of disciplines. These tools can expand our understanding of fundamental biological processes and create new opportunities for therapeutic designs. The rapid evolution of these methods has also catalyzed a new era of genomics that includes multiple approaches to functionally characterize and manipulate the regulation of genomic information. Here, we review the recent advances of the most widely adopted genome engineering platforms and their application to functional genomics. This includes engineered zinc finger proteins, TALEs/TALENs, and the CRISPR/Cas9 system as nucleases for genome editing, transcription factors for epigenome editing, and other emerging applications. We also present current and potential future applications of these tools, as well as their current limitations and areas for future advances. PMID:26430154

  6. Exploring Other Genomes: Bacteria.

    ERIC Educational Resources Information Center

    Flannery, Maura C.

    2001-01-01

    Points out the importance of genomes other than the human genome project and provides information on the identified bacterial genomes Pseudomonas aeuroginosa, Leprosy, Cholera, Meningitis, Tuberculosis, Bubonic Plague, and plant pathogens. Considers the computer's use in genome studies. (Contains 14 references.) (YDS)

  7. Navigating yeast genome maintenance with functional genomics.

    PubMed

    Measday, Vivien; Stirling, Peter C

    2016-03-01

    Maintenance of genome integrity is a fundamental requirement of all organisms. To address this, organisms have evolved extremely faithful modes of replication, DNA repair and chromosome segregation to combat the deleterious effects of an unstable genome. Nonetheless, a small amount of genome instability is the driver of evolutionary change and adaptation, and thus a low level of instability is permitted in populations. While defects in genome maintenance almost invariably reduce fitness in the short term, they can create an environment where beneficial mutations are more likely to occur. The importance of this fact is clearest in the development of human cancer, where genome instability is a well-established enabling characteristic of carcinogenesis. This raises the crucial question: what are the cellular pathways that promote genome maintenance and what are their mechanisms? Work in model organisms, in particular the yeast Saccharomyces cerevisiae, has provided the global foundations of genome maintenance mechanisms in eukaryotes. The development of pioneering genomic tools inS. cerevisiae, such as the systematic creation of mutants in all nonessential and essential genes, has enabled whole-genome approaches to identifying genes with roles in genome maintenance. Here, we review the extensive whole-genome approaches taken in yeast, with an emphasis on functional genomic screens, to understand the genetic basis of genome instability, highlighting a range of genetic and cytological screening modalities. By revealing the biological pathways and processes regulating genome integrity, these analyses contribute to the systems-level map of the yeast cell and inform studies of human disease, especially cancer. PMID:26323482

  8. Genome Maps, a new generation genome browser.

    PubMed

    Medina, Ignacio; Salavert, Francisco; Sanchez, Rubén; de Maria, Alejandro; Alonso, Roberto; Escobar, Pablo; Bleda, Marta; Dopazo, Joaquín

    2013-07-01

    Genome browsers have gained importance as more genomes and related genomic information become available. However, the increase of information brought about by new generation sequencing technologies is, at the same time, causing a subtle but continuous decrease in the efficiency of conventional genome browsers. Here, we present Genome Maps, a genome browser that implements an innovative model of data transfer and management. The program uses highly efficient technologies from the new HTML5 standard, such as scalable vector graphics, that optimize workloads at both server and client sides and ensure future scalability. Thus, data management and representation are entirely carried out by the browser, without the need of any Java Applet, Flash or other plug-in technology installation. Relevant biological data on genes, transcripts, exons, regulatory features, single-nucleotide polymorphisms, karyotype and so forth, are imported from web services and are available as tracks. In addition, several DAS servers are already included in Genome Maps. As a novelty, this web-based genome browser allows the local upload of huge genomic data files (e.g. VCF or BAM) that can be dynamically visualized in real time at the client side, thus facilitating the management of medical data affected by privacy restrictions. Finally, Genome Maps can easily be integrated in any web application by including only a few lines of code. Genome Maps is an open source collaborative initiative available in the GitHub repository (https://github.com/compbio-bigdata-viz/genome-maps). Genome Maps is available at: http://www.genomemaps.org. PMID:23748955

  9. Genome Maps, a new generation genome browser

    PubMed Central

    Medina, Ignacio; Salavert, Francisco; Sanchez, Rubén; de Maria, Alejandro; Alonso, Roberto; Escobar, Pablo; Bleda, Marta; Dopazo, Joaquín

    2013-01-01

    Genome browsers have gained importance as more genomes and related genomic information become available. However, the increase of information brought about by new generation sequencing technologies is, at the same time, causing a subtle but continuous decrease in the efficiency of conventional genome browsers. Here, we present Genome Maps, a genome browser that implements an innovative model of data transfer and management. The program uses highly efficient technologies from the new HTML5 standard, such as scalable vector graphics, that optimize workloads at both server and client sides and ensure future scalability. Thus, data management and representation are entirely carried out by the browser, without the need of any Java Applet, Flash or other plug-in technology installation. Relevant biological data on genes, transcripts, exons, regulatory features, single-nucleotide polymorphisms, karyotype and so forth, are imported from web services and are available as tracks. In addition, several DAS servers are already included in Genome Maps. As a novelty, this web-based genome browser allows the local upload of huge genomic data files (e.g. VCF or BAM) that can be dynamically visualized in real time at the client side, thus facilitating the management of medical data affected by privacy restrictions. Finally, Genome Maps can easily be integrated in any web application by including only a few lines of code. Genome Maps is an open source collaborative initiative available in the GitHub repository (https://github.com/compbio-bigdata-viz/genome-maps). Genome Maps is available at: http://www.genomemaps.org. PMID:23748955

  10. Genomic Encyclopedia of Fungi

    SciTech Connect

    Grigoriev, Igor

    2012-08-10

    Genomes of fungi relevant to energy and environment are in focus of the Fungal Genomic Program at the US Department of Energy Joint Genome Institute (JGI). Its key project, the Genomics Encyclopedia of Fungi, targets fungi related to plant health (symbionts, pathogens, and biocontrol agents) and biorefinery processes (cellulose degradation, sugar fermentation, industrial hosts), and explores fungal diversity by means of genome sequencing and analysis. Over 150 fungal genomes have been sequenced by JGI to date and released through MycoCosm (www.jgi.doe.gov/fungi), a fungal web-portal, which integrates sequence and functional data with genome analysis tools for user community. Sequence analysis supported by functional genomics leads to developing parts list for complex systems ranging from ecosystems of biofuel crops to biorefineries. Recent examples of such parts suggested by comparative genomics and functional analysis in these areas are presented here.

  11. JGI Fungal Genomics Program

    SciTech Connect

    Grigoriev, Igor V.

    2011-03-14

    Genomes of energy and environment fungi are in focus of the Fungal Genomic Program at the US Department of Energy Joint Genome Institute (JGI). Its key project, the Genomics Encyclopedia of Fungi, targets fungi related to plant health (symbionts, pathogens, and biocontrol agents) and biorefinery processes (cellulose degradation, sugar fermentation, industrial hosts), and explores fungal diversity by means of genome sequencing and analysis. Over 50 fungal genomes have been sequenced by JGI to date and released through MycoCosm (www.jgi.doe.gov/fungi), a fungal web-portal, which integrates sequence and functional data with genome analysis tools for user community. Sequence analysis supported by functional genomics leads to developing parts list for complex systems ranging from ecosystems of biofuel crops to biorefineries. Recent examples of such 'parts' suggested by comparative genomics and functional analysis in these areas are presented here

  12. Genomics and Health Impact Update

    MedlinePlus

    ... Genomics in Practice Newborn Screening Pharmacogenomics Reproductive Health Tools and Databases About the Genomics & Health Impact Update The Office of Public Health Genomics provides updated and credible ...

  13. 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

  14. Integrating sequence, evolution and functional genomics in regulatory genomics

    PubMed Central

    Vingron, Martin; Brazma, Alvis; Coulson, Richard; van Helden, Jacques; Manke, Thomas; Palin, Kimmo; Sand, Olivier; Ukkonen, Esko

    2009-01-01

    With genome analysis expanding from the study of genes to the study of gene regulation, 'regulatory genomics' utilizes sequence information, evolution and functional genomics measurements to unravel how regulatory information is encoded in the genome. PMID:19226437

  15. Genomic Data Commons | Office of Cancer Genomics

    Cancer.gov

    The NCI’s Center for Cancer Genomics launches the Genomic Data Commons (GDC), a unified data sharing platform for the cancer research community. The mission of the GDC is to enable data sharing across the entire cancer research community, to ultimately support precision medicine in oncology.

  16. Harvesting rice's dispensable genome.

    PubMed

    Wing, Rod A

    2015-01-01

    A rapid and cost-effective approach has been developed to harvest and map the dispensable genome, that is, population-level natural sequence variation within a species that is not present in static genome assemblies. PMID:26429765

  17. Libraries for genomic SELEX.

    PubMed Central

    Singer, B S; Shtatland, T; Brown, D; Gold, L

    1997-01-01

    An increasing number of proteins are being identified that regulate gene expression by binding specific nucleic acidsin vivo. A method termed genomic SELEX facilitates the rapid identification of networks of protein-nucleic acid interactions by identifying within the genomic sequences of an organism the highest affinity sites for any protein of the organism. As with its progenitor, SELEX of random-sequence nucleic acids, genomic SELEX involves iterative binding, partitioning, and amplification of nucleic acids. The two methods differ in that the variable region of the nucleic acid library for genomic SELEX is derived from the genome of an organism. We have used a quick and simple method to construct Escherichia coli, Saccharomyces cerevisiae, and human genomic DNA PCR libraries that can be transcribed with T7 RNA polymerase. We present evidence that the libraries contain overlapping inserts starting at most of the positions within the genome, making these libraries suitable for genomic SELEX. PMID:9016629

  18. Genomic Data Commons launches

    Cancer.gov

    The Genomic Data Commons (GDC), a unified data system that promotes sharing of genomic and clinical data between researchers, launched today with a visit from Vice President Joe Biden to the operations center at the University of Chicago.

  19. GENOMICS AND ENVIRONMENTAL RESEARCH

    EPA Science Inventory

    The impact of recently developed and emerging genomics technologies on environmental sciences has significant implications for human and ecological risk assessment issues. The linkage of data generated from genomics, transcriptomics, proteomics, metabalomics, and ecology can be ...

  20. Exploiting the genome

    SciTech Connect

    Block, S.; Cornwall, J.; Dyson, F.; Koonin, S.; Lewis, N.; Schwitters, R.

    1998-09-11

    In 1997, JASON conducted a DOE-sponsored study of the human genome project with special emphasis on the areas of technology, quality assurance and quality control, and informatics. The present study has two aims: first, to update the 1997 Report in light of recent developments in genome sequencing technology, and second, to consider possible roles for the DOE in the ''post-genomic" era, following acquisition of the complete human genome sequence.

  1. COMPARATIVE GENOMICS IN LEGUMES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The legume plant family will soon include three sequenced genomes. The majority of the gene-containing portions of the model legumes Medicago truncatula and Lotus japonicus have been sequenced in clone-by-clone projects, and the sequencing of the soybean genome is underway in a whole-genome shotgun ...

  2. Whole Genome Selection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Whole genome selection (WGS) is an approach to using DNA markers that are distributed throughout the entire genome. Genes affecting most economically-important traits are distributed throughout the genome and there are relatively few that have large effects with many more genes with progressively sm...

  3. Genomics and functional genomics with haloarchaea.

    PubMed

    Soppa, J; Baumann, A; Brenneis, M; Dambeck, M; Hering, O; Lange, C

    2008-09-01

    The first haloarchaeal genome was published in 2000 and today five genome sequences are available. Transcriptome and proteome analyses have been established for two and three haloarchaeal species, respectively, and more than 20 studies using these functional genomic approaches have been published in the last two years. These studies gave global overviews of metabolic regulation (aerobic and anaerobic respiration, phototrophy, carbon source usage), stress response (UV, X-rays, transition metals, osmotic and temperature stress), cell cycle-dependent transcript level regulation, and transcript half-lives. The only translatome analysis available for any prokaryotic species revealed that 10 and 20% of all transcripts are translationally regulated in Haloferax volcanii and Halobacterium salinarum, respectively. Very effective methods for the construction of in frame deletion mutants have been established recently for haloarchaea and are intensively used to unravel the biological roles of genes in this group. Bioinformatic analyses include both cross-genome comparisons as well as integration of genomic data with experimental results. The first systems biology approaches have been performed that used experimental data to construct predictive models of gene expression and metabolism, respectively. In this contribution the current status of genomics, functional genomics, and molecular genetics of haloarchaea is summarized and selected examples are discussed. PMID:18493745

  4. Chromium and Genomic Stability

    PubMed Central

    Wise, Sandra S.; Wise, John Pierce

    2014-01-01

    Many metals serve as micronutrients which protect against genomic instability. Chromium is most abundant in its trivalent and hexavalent forms. Trivalent chromium has historically been considered an essential element, though recent data indicate that while it can have pharmacological effects and value, it is not essential. There are no data indicating that trivalent chromium promotes genomic stability and, instead may promote genomic instability. Hexavalent chromium is widely accepted as highly toxic and carcinogenic with no nutritional value. Recent data indicate that it causes genomic instability and also has no role in promoting genomic stability. PMID:22192535

  5. The Genomic Medicine Game.

    PubMed

    Tran, Elvis; de Andrés-Galiana, Enrique J; Benitez, Sonia; Martin-Sanchez, Fernando; Lopez-Campos, Guillermo H

    2016-01-01

    With advancements in genomics technology, health care has been improving and new paradigms of medicine such as genomic medicine have evolved. The education of clinicians, researchers and students to face the challenges posed by these new approaches, however, has been often lagging behind. From this the Genomic Medicine Game, an educational tool, was created for the purpose of conceptualizing the key components of Genomic Medicine. A number of phenotype-genotype associations were found through a literature review, which was used to be a base for the concepts the Genomic Medicine Game would focus on. Built in Java, the game was successfully tested with promising results. PMID:27577486

  6. Microbial genomic taxonomy.

    PubMed

    Thompson, Cristiane C; Chimetto, Luciane; Edwards, Robert A; Swings, Jean; Stackebrandt, Erko; Thompson, Fabiano L

    2013-01-01

    A need for a genomic species definition is emerging from several independent studies worldwide. In this commentary paper, we discuss recent studies on the genomic taxonomy of diverse microbial groups and a unified species definition based on genomics. Accordingly, strains from the same microbial species share >95% Average Amino Acid Identity (AAI) and Average Nucleotide Identity (ANI), >95% identity based on multiple alignment genes, <10 in Karlin genomic signature, and > 70% in silico Genome-to-Genome Hybridization similarity (GGDH). Species of the same genus will form monophyletic groups on the basis of 16S rRNA gene sequences, Multilocus Sequence Analysis (MLSA) and supertree analysis. In addition to the established requirements for species descriptions, we propose that new taxa descriptions should also include at least a draft genome sequence of the type strain in order to obtain a clear outlook on the genomic landscape of the novel microbe. The application of the new genomic species definition put forward here will allow researchers to use genome sequences to define simultaneously coherent phenotypic and genomic groups. PMID:24365132

  7. The Bluejay genome browser.

    PubMed

    Soh, Jung; Gordon, Paul M K; Sensen, Christoph W

    2012-03-01

    The Bluejay genome browser is a stand-alone visualization tool for the multi-scale viewing of annotated genomes and other genomic elements. Bluejay allows users to customize display features to suit their needs, and produces publication-quality graphics. Bluejay provides a multitude of ways to interrelate biological data at the genome scale. Users can load gene expression data into a genome display for expression visualization in context. Multiple genomes can be compared concurrently, including time series expression data, based on Gene Ontology labels. External, context-sensitive biological Web Services are linked to the displayed genomic elements ad hoc for in-depth genomic data analysis and interpretation. Users can mark multiple points of interest in a genome by creating waypoints, and exploit them for easy navigation of single or multiple genomes. Using this comprehensive visual environment, users can study a gene not just in relation to its genome, but also its transcriptome and evolutionary origins. Written in Java, Bluejay is platform-independent and is freely available from http://bluejay.ucalgary.ca. PMID:22389011

  8. Bacterial Genome Instability

    PubMed Central

    Darmon, Elise

    2014-01-01

    SUMMARY Bacterial genomes are remarkably stable from one generation to the next but are plastic on an evolutionary time scale, substantially shaped by horizontal gene transfer, genome rearrangement, and the activities of mobile DNA elements. This implies the existence of a delicate balance between the maintenance of genome stability and the tolerance of genome instability. In this review, we describe the specialized genetic elements and the endogenous processes that contribute to genome instability. We then discuss the consequences of genome instability at the physiological level, where cells have harnessed instability to mediate phase and antigenic variation, and at the evolutionary level, where horizontal gene transfer has played an important role. Indeed, this ability to share DNA sequences has played a major part in the evolution of life on Earth. The evolutionary plasticity of bacterial genomes, coupled with the vast numbers of bacteria on the planet, substantially limits our ability to control disease. PMID:24600039

  9. UCSC genome browser tutorial.

    PubMed

    Zweig, Ann S; Karolchik, Donna; Kuhn, Robert M; Haussler, David; Kent, W James

    2008-08-01

    The University of California Santa Cruz (UCSC) Genome Bioinformatics website consists of a suite of free, open-source, on-line tools that can be used to browse, analyze, and query genomic data. These tools are available to anyone who has an Internet browser and an interest in genomics. The website provides a quick and easy-to-use visual display of genomic data. It places annotation tracks beneath genome coordinate positions, allowing rapid visual correlation of different types of information. Many of the annotation tracks are submitted by scientists worldwide; the others are computed by the UCSC Genome Bioinformatics group from publicly available sequence data. It also allows users to upload and display their own experimental results or annotation sets by creating a custom track. The suite of tools, downloadable data files, and links to documentation and other information can be found at http://genome.ucsc.edu/. PMID:18514479

  10. Variations in genome mass.

    PubMed

    Wachtel, S S; Tiersch, T R

    1993-02-01

    1. Genome size varies considerably among vertebrates, ranging from less than 1 pg to more than 200 pg; the amount of DNA differing among individuals in a population can equal the amount in the entire structural gene complement. 2. Recent technological advances permit evaluation of genome size variation at several levels including sub-chromosomal, chromosomal and cellular. 3. Genome size variation may also be viewed from taxonomic levels, and across evolutionary time frames. 4. As sources of genome size variation are identified and studied, the conundrum of the C-value paradox (lack of correlations among genome size, genomic complexity and phylogenetic status of organisms) may prove to be more apparent than real. 5. For example, the limited and relatively constant genome size of avians may be related to the physiological constraints of flight. PMID:8462275

  11. COMPARATIVE TRANSCRIPTOME ANALYSIS OF SALT-TOLERANT WHEAT GERMPLASM LINES USING GENOME ARRAYS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Salt-tolerant wheat lines W4909 and W4910 were derived from a cross between AJDAj5 (a disomic addition line carrying a pair of Eb chromosomes from Thinopyrum junceum) and Ph1 (a line having the Ph1 allele from Aegilops speltoides, which promotes homoeologous recombination). Both lines have greater ...

  12. Genomics of sorghum.

    PubMed

    Paterson, Andrew H

    2008-01-01

    Sorghum (Sorghum bicolor (L.) Moench) is a subject of plant genomics research based on its importance as one of the world's leading cereal crops, a biofuels crop of high and growing importance, a progenitor of one of the world's most noxious weeds, and a botanical model for many tropical grasses with complex genomes. A rich history of genome analysis, culminating in the recent complete sequencing of the genome of a leading inbred, provides a foundation for invigorating progress toward relating sorghum genes to their functions. Further characterization of the genomes other than Saccharinae cereals may shed light on mechanisms, levels, and patterns of evolution of genome size and structure, laying the foundation for further study of sugarcane and other economically important members of the group. PMID:18483564

  13. The tiniest tiny genomes.

    PubMed

    Moran, Nancy A; Bennett, Gordon M

    2014-01-01

    Starting in 2006, surprisingly tiny genomes have been discovered from numerous bacterial symbionts of insect hosts. Despite their size, each retains some genes that enable provisioning of limiting nutrients or other capabilities required by hosts. Genome sequence analyses show that genome reduction is an ongoing process, resulting in a continuum of sizes, with the smallest genome currently known at 112 kilobases. Genome reduction is typical in host-restricted symbionts and pathogens, but the tiniest genomes are restricted to symbionts required by hosts and restricted to specialized host cells, resulting from long coevolution with hosts. Genes are lost in all functional categories, but core genes for central informational processes, including genes encoding ribosomal proteins, are mostly retained, whereas genes underlying production of cell envelope components are especially depleted. Thus, these entities retain cell-like properties but are heavily dependent on coadaptation of hosts, which continuously evolve to support the symbionts upon which they depend. PMID:24995872

  14. Querying genomic databases

    SciTech Connect

    Baehr, A.; Hagstrom, R.; Joerg, D.; Overbeek, R.

    1991-09-01

    A natural-language interface has been developed that retrieves genomic information by using a simple subset of English. The interface spares the biologist from the task of learning database-specific query languages and computer programming. Currently, the interface deals with the E. coli genome. It can, however, be readily extended and shows promise as a means of easy access to other sequenced genomic databases as well.

  15. Genome Aliquoting Revisited

    NASA Astrophysics Data System (ADS)

    Warren, Robert; Sankoff, David

    We prove that the genome aliquoting problem, the problem of finding a recent polyploid ancestor of a genome, with breakpoint distance can be solved in polynomial time. We propose an aliquoting algorithm that is a 2-approximation for the genome aliquoting problem with double cut and join distance, improving upon the previous best solution to this problem, Feijão and Meidanis' 4-approximation algorithm.

  16. Physician Assistant Genomic Competencies.

    PubMed

    Goldgar, Constance; Michaud, Ed; Park, Nguyen; Jenkins, Jean

    2016-09-01

    Genomic discoveries are increasingly being applied to the clinical care of patients. All physician assistants (PAs) need to acquire competency in genomics to provide the best possible care for patients within the scope of their practice. In this article, we present an updated version of PA genomic competencies and learning outcomes in a framework that is consistent with the current medical education guidelines and the collaborative nature of PAs in interprofessional health care teams. PMID:27490287

  17. Filarial and Wolbachia genomics.

    PubMed

    Scott, A L; Ghedin, E; Nutman, T B; McReynolds, L A; Poole, C B; Slatko, B E; Foster, J M

    2012-01-01

    Filarial nematode parasites, the causative agents for a spectrum of acute and chronic diseases including lymphatic filariasis and river blindness, threaten the well-being and livelihood of hundreds of millions of people in the developing regions of the world. The 2007 publication on a draft assembly of the 95-Mb genome of the human filarial parasite Brugia malayi- representing the first helminth parasite genome to be sequenced - has been followed in rapid succession by projects that have resulted in the genome sequencing of six additional filarial species, seven nonfilarial nematode parasites of animals and nearly 30 plant parasitic and free-living species. Parallel to the genomic sequencing, transcriptomic and proteomic projects have facilitated genome annotation, expanded our understanding of stage-associated gene expression and provided a first look at the role of epigenetic regulation of filarial genomes through microRNAs. The expansion in filarial genomics will also provide a significant enrichment in our knowledge of the diversity and variability in the genomes of the endosymbiotic bacterium Wolbachia leading to a better understanding of the genetic principles that govern filarial-Wolbachia mutualism. The goal here is to provide an overview of the trends and advances in filarial and Wolbachia genomics. PMID:22098559

  18. Fungal Genomics Program

    SciTech Connect

    Grigoriev, Igor

    2012-03-12

    The JGI Fungal Genomics Program aims to scale up sequencing and analysis of fungal genomes to explore the diversity of fungi important for energy and the environment, and to promote functional studies on a system level. Combining new sequencing technologies and comparative genomics tools, JGI is now leading the world in fungal genome sequencing and analysis. Over 120 sequenced fungal genomes with analytical tools are available via MycoCosm (www.jgi.doe.gov/fungi), a web-portal for fungal biologists. Our model of interacting with user communities, unique among other sequencing centers, helps organize these communities, improves genome annotation and analysis work, and facilitates new larger-scale genomic projects. This resulted in 20 high-profile papers published in 2011 alone and contributing to the Genomics Encyclopedia of Fungi, which targets fungi related to plant health (symbionts, pathogens, and biocontrol agents) and biorefinery processes (cellulose degradation, sugar fermentation, industrial hosts). Our next grand challenges include larger scale exploration of fungal diversity (1000 fungal genomes), developing molecular tools for DOE-relevant model organisms, and analysis of complex systems and metagenomes.

  19. Genomics of Clostridium tetani.

    PubMed

    Brüggemann, Holger; Brzuszkiewicz, Elzbieta; Chapeton-Montes, Diana; Plourde, Lucile; Speck, Denis; Popoff, Michel R

    2015-05-01

    Genomic information about Clostridium tetani, the causative agent of the tetanus disease, is scarce. The genome of strain E88, a strain used in vaccine production, was sequenced about 10 years ago. One additional genome (strain 12124569) has recently been released. Here we report three new genomes of C. tetani and describe major differences among all five C. tetani genomes. They all harbor tetanus-toxin-encoding plasmids that contain highly conserved genes for TeNT (tetanus toxin), TetR (transcriptional regulator of TeNT) and ColT (collagenase), but substantially differ in other plasmid regions. The chromosomes share a large core genome that contains about 85% of all genes of a given chromosome. The non-core chromosome comprises mainly prophage-like genomic regions and genes encoding environmental interaction and defense functions (e.g. surface proteins, restriction-modification systems, toxin-antitoxin systems, CRISPR/Cas systems) and other fitness functions (e.g. transport systems, metabolic activities). This new genome information will help to assess the level of genome plasticity of the species C. tetani and provide the basis for detailed comparative studies. PMID:25638019

  20. Between two fern genomes.

    PubMed

    Sessa, Emily B; Banks, Jo Ann; Barker, Michael S; Der, Joshua P; Duffy, Aaron M; Graham, Sean W; Hasebe, Mitsuyasu; Langdale, Jane; Li, Fay-Wei; Marchant, D Blaine; Pryer, Kathleen M; Rothfels, Carl J; Roux, Stanley J; Salmi, Mari L; Sigel, Erin M; Soltis, Douglas E; Soltis, Pamela S; Stevenson, Dennis W; Wolf, Paul G

    2014-01-01

    Ferns are the only major lineage of vascular plants not represented by a sequenced nuclear genome. This lack of genome sequence information significantly impedes our ability to understand and reconstruct genome evolution not only in ferns, but across all land plants. Azolla and Ceratopteris are ideal and complementary candidates to be the first ferns to have their nuclear genomes sequenced. They differ dramatically in genome size, life history, and habit, and thus represent the immense diversity of extant ferns. Together, this pair of genomes will facilitate myriad large-scale comparative analyses across ferns and all land plants. Here we review the unique biological characteristics of ferns and describe a number of outstanding questions in plant biology that will benefit from the addition of ferns to the set of taxa with sequenced nuclear genomes. We explain why the fern clade is pivotal for understanding genome evolution across land plants, and we provide a rationale for how knowledge of fern genomes will enable progress in research beyond the ferns themselves. PMID:25324969

  1. [Landscape and ecological genomics].

    PubMed

    2013-10-01

    Landscape genomics is the modern version of landscape genetics, a discipline that arose approximately 10 years ago as a combination of population genetics, landscape ecology, and spatial statistics. It studies the effects of environmental variables on gene flow and other microevolutionary processes that determine genetic connectivity and variations in populations. In contrast to population genetics, it operates at the level of individual specimens rather than at the level of population samples. Another important difference between landscape genetics and genomics and population genetics is that, in the former, the analysis of gene flow and local adaptations takes quantitative account of landforms and features of the matrix, i.e., hostile spaces that separate species habitats. Landscape genomics is a part of population ecogenomics, which, along with community genomics, is a major part of ecological genomics. One of the principal purposes of landscape genomics is the identification and differentiation of various genome-wide and locus-specific effects. The approaches and computation tools developed for combined analysis of genomic and landscape variables make it possible to detect adaptation-related genome fragments, which facilitates the planning of conservation efforts and the prediction of species' fate in response to expected changes in the environment. PMID:25508669

  2. [Landscape and ecological genomics].

    PubMed

    Tetushkin, E Ia

    2013-10-01

    Landscape genomics is the modern version of landscape genetics, a discipline that arose approximately 10 years ago as a combination of population genetics, landscape ecology, and spatial statistics. It studies the effects of environmental variables on gene flow and other microevolutionary processes that determine genetic connectivity and variations in populations. In contrast to population genetics, it operates at the level of individual specimens rather than at the level of population samples. Another important difference between landscape genetics and genomics and population genetics is that, in the former, the analysis of gene flow and local adaptations takes quantitative account of landforms and features of the matrix, i.e., hostile spaces that separate species habitats. Landscape genomics is a part of population ecogenomics, which, along with community genomics, is a major part of ecological genomics. One of the principal purposes of landscape genomics is the identification and differentiation of various genome-wide and locus-specific effects. The approaches and computation tools developed for combined analysis of genomic and landscape variables make it possible to detect adaptation-related genome fragments, which facilitates the planning of conservation efforts and the prediction of species' fate in response to expected changes in the environment. PMID:25474890

  3. Between Two Fern Genomes

    PubMed Central

    2014-01-01

    Ferns are the only major lineage of vascular plants not represented by a sequenced nuclear genome. This lack of genome sequence information significantly impedes our ability to understand and reconstruct genome evolution not only in ferns, but across all land plants. Azolla and Ceratopteris are ideal and complementary candidates to be the first ferns to have their nuclear genomes sequenced. They differ dramatically in genome size, life history, and habit, and thus represent the immense diversity of extant ferns. Together, this pair of genomes will facilitate myriad large-scale comparative analyses across ferns and all land plants. Here we review the unique biological characteristics of ferns and describe a number of outstanding questions in plant biology that will benefit from the addition of ferns to the set of taxa with sequenced nuclear genomes. We explain why the fern clade is pivotal for understanding genome evolution across land plants, and we provide a rationale for how knowledge of fern genomes will enable progress in research beyond the ferns themselves. PMID:25324969

  4. The gene Sr33, an ortholog of barley Mla genes, encodes resistance to wheat stem rust race Ug99.

    PubMed

    Periyannan, Sambasivam; Moore, John; Ayliffe, Michael; Bansal, Urmil; Wang, Xiaojing; Huang, Li; Deal, Karin; Luo, Mingcheng; Kong, Xiuying; Bariana, Harbans; Mago, Rohit; McIntosh, Robert; Dodds, Peter; Dvorak, Jan; Lagudah, Evans

    2013-08-16

    Wheat stem rust, caused by the fungus Puccinia graminis f. sp. tritici, afflicts bread wheat (Triticum aestivum). New virulent races collectively referred to as "Ug99" have emerged, which threaten global wheat production. The wheat gene Sr33, introgressed from the wild relative Aegilops tauschii into bread wheat, confers resistance to diverse stem rust races, including the Ug99 race group. We cloned Sr33, which encodes a coiled-coil, nucleotide-binding, leucine-rich repeat protein. Sr33 is orthologous to the barley (Hordeum vulgare) Mla mildew resistance genes that confer resistance to Blumeria graminis f. sp. hordei. The wheat Sr33 gene functions independently of RAR1, SGT1, and HSP90 chaperones. Haplotype analysis from diverse collections of Ae. tauschii placed the origin of Sr33 resistance near the southern coast of the Caspian Sea. PMID:23811228

  5. Genomics of Disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This edited book represents the 23rd symposium in the Stadler Genetics Symposia series, and the general theme of this conference was "The Genomics of Disease." The 24 national and international speakers were invited to discuss their world-class research into the advances that genomics has made on c...

  6. Genomics for Weed Science

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Numerous genomic-based studies have provided insight to the physiological and evolutionary processes involved in developmental and environmental processes of model plants such as arabidopsis and rice. However, far fewer efforts have been attempted to use genomic resources to study physiological and ...

  7. Unlocking the bovine genome

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The draft genome sequence of cattle (Bos taurus) has now been analyzed by the Bovine Genome Sequencing and Analysis Consortium and the Bovine HapMap Consortium, which together represent an extensive collaboration involving more than 300 scientists from 25 different countries. ...

  8. Genetics and Genomics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Good progress is being made on genetics and genomics of sugar beet, however it is in process and the tools are now being generated and some results are being analyzed. The GABI BeetSeq project released a first draft of the sugar beet genome of KWS2320, a dihaploid (see http://bvseq.molgen.mpg.de/Gen...

  9. Development of Genomic GMACE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The use of genomics to enhance national genetic evaluation systems of dairy cattle is quickly becoming standard practice. The current MACE procedure used by Interbull may not accommodate these new “genomically-enhanced” national evaluations. An important assumption in MACE may no longer be valid in ...

  10. GENOME OF HORSEPOX VIRUS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Here we present the genomic sequence of horsepox virus (HSPV) isolate MNR-76, an orthopoxvirus (OPV) isolated in 1976 from diseased Mongolian horses. The 212 kbp genome contained 7.5 kbp inverted terminal repeats (ITR) and lacked extensive terminal tandem repetition. HSPV contained 236 ORFs with sim...

  11. Genomic Instability and Cancer

    PubMed Central

    Yao, Yixin; Dai, Wei

    2014-01-01

    Genomic instability is a characteristic of most cancer cells. It is an increased tendency of genome alteration during cell division. Cancer frequently results from damage to multiple genes controlling cell division and tumor suppressors. It is known that genomic integrity is closely monitored by several surveillance mechanisms, DNA damage checkpoint, DNA repair machinery and mitotic checkpoint. A defect in the regulation of any of these mechanisms often results in genomic instability, which predisposes the cell to malignant transformation. Posttranslational modifications of the histone tails are closely associated with regulation of the cell cycle as well as chromatin structure. Nevertheless, DNA methylation status is also related to genomic integrity. We attempt to summarize recent developments in this field and discuss the debate of driving force of tumor initiation and progression. PMID:25541596

  12. Microbial Genomes Multiply

    NASA Technical Reports Server (NTRS)

    Doolittle, Russell F.

    2002-01-01

    The publication of the first complete sequence of a bacterial genome in 1995 was a signal event, underscored by the fact that the article has been cited more than 2,100 times during the intervening seven years. It was a marvelous technical achievement, made possible by automatic DNA-sequencing machines. The feat is the more impressive in that complete genome sequencing has now been adopted in many different laboratories around the world. Four years ago in these columns I examined the situation after a dozen microbial genomes had been completed. Now, with upwards of 60 microbial genome sequences determined and twice that many in progress, it seems reasonable to assess just what is being learned. Are new concepts emerging about how cells work? Have there been practical benefits in the fields of medicine and agriculture? Is it feasible to determine the genomic sequence of every bacterial species on Earth? The answers to these questions maybe Yes, Perhaps, and No, respectively.

  13. Phytozome Comparative Plant Genomics Portal

    SciTech Connect

    Goodstein, David; Batra, Sajeev; Carlson, Joseph; Hayes, Richard; Phillips, Jeremy; Shu, Shengqiang; Schmutz, Jeremy; Rokhsar, Daniel

    2014-09-09

    The Dept. of Energy Joint Genome Institute is a genomics user facility supporting DOE mission science in the areas of Bioenergy, Carbon Cycling, and Biogeochemistry. The Plant Program at the JGI applies genomic, analytical, computational and informatics platforms and methods to: 1. Understand and accelerate the improvement (domestication) of bioenergy crops 2. Characterize and moderate plant response to climate change 3. Use comparative genomics to identify constrained elements and infer gene function 4. Build high quality genomic resource platforms of JGI Plant Flagship genomes for functional and experimental work 5. Expand functional genomic resources for Plant Flagship genomes

  14. 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

  15. Genome size evolution: sizing mammalian genomes.

    PubMed

    Redi, C A; Capanna, E

    2012-01-01

    The study of genome size (GS) and its variation is so fascinating to the scientific community because it constitutes the link between the present-day analytical and molecular studies of the genome and the old trunk of the holistic and synthetic view of the genome. The GS of several taxa vary over a broad range and do not correlate with the complexity of the organisms (the C-value paradox). However, the biology of transposable elements has let us reach a satisfactory view of the molecular mechanisms that give rise to GS variation and novelties, providing a less perplexing view of the significance of the GS (C-enigma). The knowledge of the composition and structure of a genome is a pre-requisite for trying to understand the evolution of the main genome signature: its size. The radiation of mammals provides an approximately 180-million-year test case for theories of how GS evolves. It has been found from data-mining GS databases that GS is a useful cyto-taxonomical instrument at the level of orders/superorders, providing genomic signatures characterizing Monotremata, Marsupialia, Afrotheria, Xenarthra, Laurasiatheria, and Euarchontoglires. A hypothetical ancestral mammalian-like GS of 2.9-3.7 pg has been suggested. This value appears compatible with the average values calculated for the high systematic levels of the extant Monotremata (∼2.97 pg) and Marsupialia (∼4.07 pg), suggesting invasion of mobile DNA elements concurrently with the separation of the older clades of Afrotheria (∼5.5 pg) and Xenarthra (∼4.5 pg) with larger GS, leaving the Euarchontoglires (∼3.4 pg) and Laurasiatheria (∼2.8 pg) genomes with fewer transposable elements. However, the paucity of GS data (546 mammalian species sized from 5,488 living species) for species, genera, and families calls for caution. Considering that mammalian species may be vanished even before they are known, GS data are sorely needed to phenotype the effects brought about by their variation and to validate any

  16. Evolution of genome architecture.

    PubMed

    Koonin, Eugene V

    2009-02-01

    Charles Darwin believed that all traits of organisms have been honed to near perfection by natural selection. The empirical basis underlying Darwin's conclusions consisted of numerous observations made by him and other naturalists on the exquisite adaptations of animals and plants to their natural habitats and on the impressive results of artificial selection. Darwin fully appreciated the importance of heredity but was unaware of the nature and, in fact, the very existence of genomes. A century and a half after the publication of the "Origin", we have the opportunity to draw conclusions from the comparisons of hundreds of genome sequences from all walks of life. These comparisons suggest that the dominant mode of genome evolution is quite different from that of the phenotypic evolution. The genomes of vertebrates, those purported paragons of biological perfection, turned out to be veritable junkyards of selfish genetic elements where only a small fraction of the genetic material is dedicated to encoding biologically relevant information. In sharp contrast, genomes of microbes and viruses are incomparably more compact, with most of the genetic material assigned to distinct biological functions. However, even in these genomes, the specific genome organization (gene order) is poorly conserved. The results of comparative genomics lead to the conclusion that the genome architecture is not a straightforward result of continuous adaptation but rather is determined by the balance between the selection pressure, that is itself dependent on the effective population size and mutation rate, the level of recombination, and the activity of selfish elements. Although genes and, in many cases, multigene regions of genomes possess elaborate architectures that ensure regulation of expression, these arrangements are evolutionarily volatile and typically change substantially even on short evolutionary scales when gene sequences diverge minimally. Thus, the observed genome

  17. The Banana Genome Hub

    PubMed Central

    Droc, Gaëtan; Larivière, Delphine; Guignon, Valentin; Yahiaoui, Nabila; This, Dominique; Garsmeur, Olivier; Dereeper, Alexis; Hamelin, Chantal; Argout, Xavier; Dufayard, Jean-François; Lengelle, Juliette; Baurens, Franc-Christophe; Cenci, Alberto; Pitollat, Bertrand; D’Hont, Angélique; Ruiz, Manuel; Rouard, Mathieu; Bocs, Stéphanie

    2013-01-01

    Banana is one of the world’s favorite fruits and one of the most important crops for developing countries. The banana reference genome sequence (Musa acuminata) was recently released. Given the taxonomic position of Musa, the completed genomic sequence has particular comparative value to provide fresh insights about the evolution of the monocotyledons. The study of the banana genome has been enhanced by a number of tools and resources that allows harnessing its sequence. First, we set up essential tools such as a Community Annotation System, phylogenomics resources and metabolic pathways. Then, to support post-genomic efforts, we improved banana existing systems (e.g. web front end, query builder), we integrated available Musa data into generic systems (e.g. markers and genetic maps, synteny blocks), we have made interoperable with the banana hub, other existing systems containing Musa data (e.g. transcriptomics, rice reference genome, workflow manager) and finally, we generated new results from sequence analyses (e.g. SNP and polymorphism analysis). Several uses cases illustrate how the Banana Genome Hub can be used to study gene families. Overall, with this collaborative effort, we discuss the importance of the interoperability toward data integration between existing information systems. Database URL: http://banana-genome.cirad.fr/ PMID:23707967

  18. Genomic Insights into Bifidobacteria

    PubMed Central

    Lee, Ju-Hoon; O'Sullivan, Daniel J.

    2010-01-01

    Summary: Since the discovery in 1899 of bifidobacteria as numerically dominant microbes in the feces of breast-fed infants, there have been numerous studies addressing their role in modulating gut microflora as well as their other potential health benefits. Because of this, they are frequently incorporated into foods as probiotic cultures. An understanding of their full interactions with intestinal microbes and the host is needed to scientifically validate any health benefits they may afford. Recently, the genome sequences of nine strains representing four species of Bifidobacterium became available. A comparative genome analysis of these genomes reveals a likely efficient capacity to adapt to their habitats, with B. longum subsp. infantis exhibiting more genomic potential to utilize human milk oligosaccharides, consistent with its habitat in the infant gut. Conversely, B. longum subsp. longum exhibits a higher genomic potential for utilization of plant-derived complex carbohydrates and polyols, consistent with its habitat in an adult gut. An intriguing observation is the loss of much of this genome potential when strains are adapted to pure culture environments, as highlighted by the genomes of B. animalis subsp. lactis strains, which exhibit the least potential for a gut habitat and are believed to have evolved from the B. animalis species during adaptation to dairy fermentation environments. PMID:20805404

  19. Ensembl comparative genomics resources

    PubMed Central

    Muffato, Matthieu; Beal, Kathryn; Fitzgerald, Stephen; Gordon, Leo; Pignatelli, Miguel; Vilella, Albert J.; Searle, Stephen M. J.; Amode, Ridwan; Brent, Simon; Spooner, William; Kulesha, Eugene; Yates, Andrew; Flicek, Paul

    2016-01-01

    Evolution provides the unifying framework with which to understand biology. The coherent investigation of genic and genomic data often requires comparative genomics analyses based on whole-genome alignments, sets of homologous genes and other relevant datasets in order to evaluate and answer evolutionary-related questions. However, the complexity and computational requirements of producing such data are substantial: this has led to only a small number of reference resources that are used for most comparative analyses. The Ensembl comparative genomics resources are one such reference set that facilitates comprehensive and reproducible analysis of chordate genome data. Ensembl computes pairwise and multiple whole-genome alignments from which large-scale synteny, per-base conservation scores and constrained elements are obtained. Gene alignments are used to define Ensembl Protein Families, GeneTrees and homologies for both protein-coding and non-coding RNA genes. These resources are updated frequently and have a consistent informatics infrastructure and data presentation across all supported species. Specialized web-based visualizations are also available including synteny displays, collapsible gene tree plots, a gene family locator and different alignment views. The Ensembl comparative genomics infrastructure is extensively reused for the analysis of non-vertebrate species by other projects including Ensembl Genomes and Gramene and much of the information here is relevant to these projects. The consistency of the annotation across species and the focus on vertebrates makes Ensembl an ideal system to perform and support vertebrate comparative genomic analyses. We use robust software and pipelines to produce reference comparative data and make it freely available. Database URL: http://www.ensembl.org. PMID:26896847

  20. Genome instability and aging.

    PubMed

    Vijg, Jan; Suh, Yousin

    2013-01-01

    Genome instability has long been implicated as the main causal factor in aging. Somatic cells are continuously exposed to various sources of DNA damage, from reactive oxygen species to UV radiation to environmental mutagens. To cope with the tens of thousands of chemical lesions introduced into the genome of a typical cell each day, a complex network of genome maintenance systems acts to remove damage and restore the correct base pair sequence. Occasionally, however, repair is erroneous, and such errors, as well as the occasional failure to correctly replicate the genome during cell division, are the basis for mutations and epimutations. There is now ample evidence that mutations accumulate in various organs and tissues of higher animals, including humans, mice, and flies. What is not known, however, is whether the frequency of these random changes is sufficient to cause the phenotypic effects generally associated with aging. The exception is cancer, an age-related disease caused by the accumulation of mutations and epimutations. Here, we first review current concepts regarding the relationship between DNA damage, repair, and mutation, as well as the data regarding genome alterations as a function of age. We then describe a model for how randomly induced DNA sequence and epigenomic variants in the somatic genomes of animals can result in functional decline and disease in old age. Finally, we discuss the genetics of genome instability in relation to longevity to address the importance of alterations in the somatic genome as a causal factor in aging and to underscore the opportunities provided by genetic approaches to develop interventions that attenuate genome instability, reduce disease risk, and increase life span. PMID:23398157

  1. Ensembl comparative genomics resources.

    PubMed

    Herrero, Javier; Muffato, Matthieu; Beal, Kathryn; Fitzgerald, Stephen; Gordon, Leo; Pignatelli, Miguel; Vilella, Albert J; Searle, Stephen M J; Amode, Ridwan; Brent, Simon; Spooner, William; Kulesha, Eugene; Yates, Andrew; Flicek, Paul

    2016-01-01

    Evolution provides the unifying framework with which to understand biology. The coherent investigation of genic and genomic data often requires comparative genomics analyses based on whole-genome alignments, sets of homologous genes and other relevant datasets in order to evaluate and answer evolutionary-related questions. However, the complexity and computational requirements of producing such data are substantial: this has led to only a small number of reference resources that are used for most comparative analyses. The Ensembl comparative genomics resources are one such reference set that facilitates comprehensive and reproducible analysis of chordate genome data. Ensembl computes pairwise and multiple whole-genome alignments from which large-scale synteny, per-base conservation scores and constrained elements are obtained. Gene alignments are used to define Ensembl Protein Families, GeneTrees and homologies for both protein-coding and non-coding RNA genes. These resources are updated frequently and have a consistent informatics infrastructure and data presentation across all supported species. Specialized web-based visualizations are also available including synteny displays, collapsible gene tree plots, a gene family locator and different alignment views. The Ensembl comparative genomics infrastructure is extensively reused for the analysis of non-vertebrate species by other projects including Ensembl Genomes and Gramene and much of the information here is relevant to these projects. The consistency of the annotation across species and the focus on vertebrates makes Ensembl an ideal system to perform and support vertebrate comparative genomic analyses. We use robust software and pipelines to produce reference comparative data and make it freely available. Database URL: http://www.ensembl.org. PMID:26896847

  2. Center for Cancer Genomics | Office of Cancer Genomics

    Cancer.gov

    The Center for Cancer Genomics (CCG) was established to unify the National Cancer Institute's activities in cancer genomics, with the goal of advancing genomics research and translating findings into the clinic to improve the precise diagnosis and treatment of cancers. In addition to promoting genomic sequencing approach

  3. Human Genome Project

    SciTech Connect

    Block, S.; Cornwall, J.; Dally, W.; Dyson, F.; Fortson, N.; Joyce, G.; Kimble, H. J.; Lewis, N.; Max, C.; Prince, T.; Schwitters, R.; Weinberger, P.; Woodin, W. H.

    1998-01-04

    The study reviews Department of Energy supported aspects of the United States Human Genome Project, the joint National Institutes of Health/Department of Energy program to characterize all human genetic material, to discover the set of human genes, and to render them accessible for further biological study. The study concentrates on issues of technology, quality assurance/control, and informatics relevant to current effort on the genome project and needs beyond it. Recommendations are presented on areas of the genome program that are of particular interest to and supported by the Department of Energy.

  4. Genomic taxonomy of vibrios

    PubMed Central

    Thompson, Cristiane C; Vicente, Ana Carolina P; Souza, Rangel C; Vasconcelos, Ana Tereza R; Vesth, Tammi; Alves, Nelson; Ussery, David W; Iida, Tetsuya; Thompson, Fabiano L

    2009-01-01

    Background Vibrio taxonomy has been based on a polyphasic approach. In this study, we retrieve useful taxonomic information (i.e. data that can be used to distinguish different taxonomic levels, such as species and genera) from 32 genome sequences of different vibrio species. We use a variety of tools to explore the taxonomic relationship between the sequenced genomes, including Multilocus Sequence Analysis (MLSA), supertrees, Average Amino Acid Identity (AAI), genomic signatures, and Genome BLAST atlases. Our aim is to analyse the usefulness of these tools for species identification in vibrios. Results We have generated four new genome sequences of three Vibrio species, i.e., V. alginolyticus 40B, V. harveyi-like 1DA3, and V. mimicus strains VM573 and VM603, and present a broad analyses of these genomes along with other sequenced Vibrio species. The genome atlas and pangenome plots provide a tantalizing image of the genomic differences that occur between closely related sister species, e.g. V. cholerae and V. mimicus. The vibrio pangenome contains around 26504 genes. The V. cholerae core genome and pangenome consist of 1520 and 6923 genes, respectively. Pangenomes might allow different strains of V. cholerae to occupy different niches. MLSA and supertree analyses resulted in a similar phylogenetic picture, with a clear distinction of four groups (Vibrio core group, V. cholerae-V. mimicus, Aliivibrio spp., and Photobacterium spp.). A Vibrio species is defined as a group of strains that share > 95% DNA identity in MLSA and supertree analysis, > 96% AAI, ≤ 10 genome signature dissimilarity, and > 61% proteome identity. Strains of the same species and species of the same genus will form monophyletic groups on the basis of MLSA and supertree. Conclusion The combination of different analytical and bioinformatics tools will enable the most accurate species identification through genomic computational analysis. This endeavour will culminate in the birth of the online

  5. Human Genome Program

    SciTech Connect

    Not Available

    1993-01-01

    The DOE Human Genome program has grown tremendously, as shown by the marked increase in the number of genome-funded projects since the last workshop held in 1991. The abstracts in this book describe the genome research of DOE-funded grantees and contractors and invited guests, and all projects are represented at the workshop by posters. The 3-day meeting includes plenary sessions on ethical, legal, and social issues pertaining to the availability of genetic data; sequencing techniques, informatics support; and chromosome and cDNA mapping and sequencing.

  6. What Is a Genome?

    PubMed Central

    Goldman, Aaron David; Landweber, Laura F.

    2016-01-01

    The genome is often described as the information repository of an organism. Whether millions or billions of letters of DNA, its transmission across generations confers the principal medium for inheritance of organismal traits. Several emerging areas of research demonstrate that this definition is an oversimplification. Here, we explore ways in which a deeper understanding of genomic diversity and cell physiology is challenging the concepts of physical permanence attached to the genome as well as its role as the sole information source for an organism. PMID:27442251

  7. Comparative primate genomics: emerging patterns of genome content and dynamics

    PubMed Central

    Rogers, Jeffrey; Gibbs, Richard A.

    2014-01-01

    Preface Advances in genome sequencing technologies have created new opportunities for comparative primate genomics. Genome assemblies have been published for several primates, with analyses of several others underway. Whole genome assemblies for the great apes provide remarkable new information about the evolutionary origins of the human genome and the processes involved. Genomic data for macaques and other nonhuman primates provide valuable insight into genetic similarities and differences among species used as models for disease-related research. This review summarizes current knowledge regarding primate genome content and dynamics and offers a series of goals for the near future. PMID:24709753

  8. Comparative primate genomics: emerging patterns of genome content and dynamics.

    PubMed

    Rogers, Jeffrey; Gibbs, Richard A

    2014-05-01

    Advances in genome sequencing technologies have created new opportunities for comparative primate genomics. Genome assemblies have been published for various primate species, and analyses of several others are underway. Whole-genome assemblies for the great apes provide remarkable new information about the evolutionary origins of the human genome and the processes involved. Genomic data for macaques and other non-human primates offer valuable insights into genetic similarities and differences among species that are used as models for disease-related research. This Review summarizes current knowledge regarding primate genome content and dynamics, and proposes a series of goals for the near future. PMID:24709753

  9. GenomeView: a next-generation genome browser

    PubMed Central

    Abeel, Thomas; Van Parys, Thomas; Saeys, Yvan; Galagan, James; Van de Peer, Yves

    2012-01-01

    Due to ongoing advances in sequencing technologies, billions of nucleotide sequences are now produced on a daily basis. A major challenge is to visualize these data for further downstream analysis. To this end, we present GenomeView, a stand-alone genome browser specifically designed to visualize and manipulate a multitude of genomics data. GenomeView enables users to dynamically browse high volumes of aligned short-read data, with dynamic navigation and semantic zooming, from the whole genome level to the single nucleotide. At the same time, the tool enables visualization of whole genome alignments of dozens of genomes relative to a reference sequence. GenomeView is unique in its capability to interactively handle huge data sets consisting of tens of aligned genomes, thousands of annotation features and millions of mapped short reads both as viewer and editor. GenomeView is freely available as an open source software package. PMID:22102585

  10. Hymenoptera Genome Database: integrating genome annotations in HymenopteraMine

    PubMed Central

    Elsik, Christine G.; Tayal, Aditi; Diesh, Colin M.; Unni, Deepak R.; Emery, Marianne L.; Nguyen, Hung N.; Hagen, Darren E.

    2016-01-01

    We report an update of the Hymenoptera Genome Database (HGD) (http://HymenopteraGenome.org), a model organism database for insect species of the order Hymenoptera (ants, bees and wasps). HGD maintains genomic data for 9 bee species, 10 ant species and 1 wasp, including the versions of genome and annotation data sets published by the genome sequencing consortiums and those provided by NCBI. A new data-mining warehouse, HymenopteraMine, based on the InterMine data warehousing system, integrates the genome data with data from external sources and facilitates cross-species analyses based on orthology. New genome browsers and annotation tools based on JBrowse/WebApollo provide easy genome navigation, and viewing of high throughput sequence data sets and can be used for collaborative genome annotation. All of the genomes and annotation data sets are combined into a single BLAST server that allows users to select and combine sequence data sets to search. PMID:26578564

  11. Hymenoptera Genome Database: integrating genome annotations in HymenopteraMine.

    PubMed

    Elsik, Christine G; Tayal, Aditi; Diesh, Colin M; Unni, Deepak R; Emery, Marianne L; Nguyen, Hung N; Hagen, Darren E

    2016-01-01

    We report an update of the Hymenoptera Genome Database (HGD) (http://HymenopteraGenome.org), a model organism database for insect species of the order Hymenoptera (ants, bees and wasps). HGD maintains genomic data for 9 bee species, 10 ant species and 1 wasp, including the versions of genome and annotation data sets published by the genome sequencing consortiums and those provided by NCBI. A new data-mining warehouse, HymenopteraMine, based on the InterMine data warehousing system, integrates the genome data with data from external sources and facilitates cross-species analyses based on orthology. New genome browsers and annotation tools based on JBrowse/WebApollo provide easy genome navigation, and viewing of high throughput sequence data sets and can be used for collaborative genome annotation. All of the genomes and annotation data sets are combined into a single BLAST server that allows users to select and combine sequence data sets to search. PMID:26578564

  12. Vita Genomics, Inc.

    PubMed

    Shih-Hsin Wu, Lawrence; Su, Chun-Lin; Chen, Ellson

    2007-06-01

    Vita Genomics, Inc., centered in Taiwan and China, aims to be a premier genomics-based biotechnological and biopharmaceutical company in the Asia-Pacific region. The company focuses on conducting pharmacogenomics research, in vitro diagnosis product development and specialty contract research services in both genomics and pharmacogenomics fields. We are now initiating a drug rescue program designed to resurrect drugs that have failed in the previous clinical trials owing to low efficacies. This program applies pharmacogenomics approaches using biomarkers to screen subsets of patients who may respond better or avoid adverse responses to the test drugs. Vita Genomics, Inc. has envisioned itself as an important player in the healthcare industry offering advanced molecular diagnostic products and services, revolutionizing thedrug-development process and providing pharmacogenomic solutions. PMID:17559355

  13. Lophotrochozoan mitochondrial genomes

    SciTech Connect

    Valles, Yvonne; Boore, Jeffrey L.

    2005-10-01

    Progress in both molecular techniques and phylogeneticmethods has challenged many of the interpretations of traditionaltaxonomy. One example is in the recognition of the animal superphylumLophotrochozoa (annelids, mollusks, echiurans, platyhelminthes,brachiopods, and other phyla), although the relationships within thisgroup and the inclusion of some phyla remain uncertain. While much ofthis progress in phylogenetic reconstruction has been based on comparingsingle gene sequences, we are beginning to see the potential of comparinglarge-scale features of genomes, such as the relative order of genes.Even though tremendous progress is being made on the sequencedetermination of whole nuclear genomes, the dataset of choice forgenome-level characters for many animals across a broad taxonomic rangeremains mitochondrial genomes. We review here what is known aboutmitochondrial genomes of the lophotrochozoans and discuss the promisethat this dataset will enable insight into theirrelationships.

  14. Androgen receptor genomic regulation

    PubMed Central

    Jin, Hong-Jian; Kim, Jung

    2013-01-01

    The transcriptional activity of the androgen receptor (AR) is not only critical for the normal development and function of the prostate but also pivotal to the onset and progression of prostate cancer (PCa). The studies of AR transcriptional regulation were previously limited to a handful of AR-target genes. Owing to the development of various high-throughput genomic technologies, significant advances have been made in recent years. Here we discuss the discoveries of genome-wide androgen-regulated genes in PCa cell lines, animal models and tissues using expression microarray and sequencing, the mapping of genomic landscapes of AR using Combining Chromatin Immunoprecipitation (ChIP)-on-chip and ChIP-seq assays, the interplay of transcriptional cofactors in defining AR binding profiles, and the genomic regulation and AR reprogramming in advanced PCa. PMID:25237629

  15. Mouse genome database 2016

    PubMed Central

    Bult, Carol J.; Eppig, Janan T.; Blake, Judith A.; Kadin, James A.; Richardson, Joel E.

    2016-01-01

    The Mouse Genome Database (MGD; http://www.informatics.jax.org) is the primary community model organism database for the laboratory mouse and serves as the source for key biological reference data related to mouse genes, gene functions, phenotypes and disease models with a strong emphasis on the relationship of these data to human biology and disease. As the cost of genome-scale sequencing continues to decrease and new technologies for genome editing become widely adopted, the laboratory mouse is more important than ever as a model system for understanding the biological significance of human genetic variation and for advancing the basic research needed to support the emergence of genome-guided precision medicine. Recent enhancements to MGD include new graphical summaries of biological annotations for mouse genes, support for mobile access to the database, tools to support the annotation and analysis of sets of genes, and expanded support for comparative biology through the expansion of homology data. PMID:26578600

  16. The genomics of adaptation.

    PubMed

    Radwan, Jacek; Babik, Wiesław

    2012-12-22

    The amount and nature of genetic variation available to natural selection affect the rate, course and outcome of evolution. Consequently, the study of the genetic basis of adaptive evolutionary change has occupied biologists for decades, but progress has been hampered by the lack of resolution and the absence of a genome-level perspective. Technological advances in recent years should now allow us to answer many long-standing questions about the nature of adaptation. The data gathered so far are beginning to challenge some widespread views of the way in which natural selection operates at the genomic level. Papers in this Special Feature of Proceedings of the Royal Society B illustrate various aspects of the broad field of adaptation genomics. This introductory article sets up a context and, on the basis of a few selected examples, discusses how genomic data can advance our understanding of the process of adaptation. PMID:23097510

  17. Genomics and vaccine development

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genomic-based approaches are driving fundamental changes in our understanding of microbiology. Comparative analysis of microbial strain is providing new insights into pathogen evolution, virulence mechanisms, and host range specificity. Most importantly, gene discovery and genetic variations can now...

  18. Platyzoan mitochondrial genomes.

    PubMed

    Wey-Fabrizius, Alexandra R; Podsiadlowski, Lars; Herlyn, Holger; Hankeln, Thomas

    2013-11-01

    Platyzoa is a putative lophotrochozoan (spiralian) subtaxon within the protostome clade of Metazoa, comprising a range of biologically diverse, mostly small worm-shaped animals. The monophyly of Platyzoa, the relationships between the putative subgroups Platyhelminthes, Gastrotricha and Gnathifera (the latter comprising at least Gnathostomulida, "Rotifera" and Acanthocephala) as well as some aspects of the internal phylogenies of these subgroups are highly debated. Here we review how complete mitochondrial (mt) genome data contribute to these debates. We highlight special features of the mt genomes and discuss problems in mtDNA phylogenies of the clade. Mitochondrial genome data seem to be insufficient to resolve the position of the platyzoan clade within the Spiralia but can help to address internal phylogenetic questions. The present review includes a tabular survey of all published platyzoan mt genomes. PMID:23274056

  19. Mouse genome database 2016.

    PubMed

    Bult, Carol J; Eppig, Janan T; Blake, Judith A; Kadin, James A; Richardson, Joel E

    2016-01-01

    The Mouse Genome Database (MGD; http://www.informatics.jax.org) is the primary community model organism database for the laboratory mouse and serves as the source for key biological reference data related to mouse genes, gene functions, phenotypes and disease models with a strong emphasis on the relationship of these data to human biology and disease. As the cost of genome-scale sequencing continues to decrease and new technologies for genome editing become widely adopted, the laboratory mouse is more important than ever as a model system for understanding the biological significance of human genetic variation and for advancing the basic research needed to support the emergence of genome-guided precision medicine. Recent enhancements to MGD include new graphical summaries of biological annotations for mouse genes, support for mobile access to the database, tools to support the annotation and analysis of sets of genes, and expanded support for comparative biology through the expansion of homology data. PMID:26578600

  20. The rise of genomics.

    PubMed

    Weissenbach, Jean

    2016-01-01

    A brief history of the development of genomics is provided. Complete sequencing of genomes of uni- and multicellular organisms is based on important progress in sequencing and bioinformatics. Evolution of these methods is ongoing and has triggered an explosion in data production and analysis. Initial analyses focused on the inventory of genes encoding proteins. Completeness and quality of gene prediction remains crucial. Genome analyses profoundly modified our views on evolution, biodiversity and contributed to the detection of new functions, yet to be fully elucidated, such as those fulfilled by non-coding RNAs. Genomics has become the basis for the study of biology and provides the molecular support for a bunch of large-scale studies, the omics. PMID:27263360

  1. Epidemiology & Genomics Research Program

    Cancer.gov

    The Epidemiology and Genomics Research Program, in the National Cancer Institute's Division of Cancer Control and Population Sciences, funds research in human populations to understand the determinants of cancer occurrence and outcomes.

  2. Genomic definition of species

    SciTech Connect

    Crkvenjakov, R.; Drmanac, R.

    1991-07-01

    The subject of this paper is the definition of species based on the assumption that genome is the fundamental level for the origin and maintenance of biological diversity. For this view to be logically consistent it is necessary to assume the existence and operation of the new law which we call genome law. For this reason the genome law is included in the explanation of species phenomenon presented here even if its precise formulation and elaboration are left for the future. The intellectual underpinnings of this definition can be traced to Goldschmidt. We wish to explore some philosophical aspects of the definition of species in terms of the genome. The point of proposing the definition on these grounds is that any real advance in evolutionary theory has to be correct in both its philosophy and its science.

  3. Molluscan Evolutionary Genomics

    SciTech Connect

    Simison, W. Brian; Boore, Jeffrey L.

    2005-12-01

    In the last 20 years there have been dramatic advances in techniques of high-throughput DNA sequencing, most recently accelerated by the Human Genome Project, a program that has determined the three billion base pair code on which we are based. Now this tremendous capability is being directed at other genome targets that are being sampled across the broad range of life. This opens up opportunities as never before for evolutionary and organismal biologists to address questions of both processes and patterns of organismal change. We stand at the dawn of a new 'modern synthesis' period, paralleling that of the early 20th century when the fledgling field of genetics first identified the underlying basis for Darwin's theory. We must now unite the efforts of systematists, paleontologists, mathematicians, computer programmers, molecular biologists, developmental biologists, and others in the pursuit of discovering what genomics can teach us about the diversity of life. Genome-level sampling for mollusks to date has mostly been limited to mitochondrial genomes and it is likely that these will continue to provide the best targets for broad phylogenetic sampling in the near future. However, we are just beginning to see an inroad into complete nuclear genome sequencing, with several mollusks and other eutrochozoans having been selected for work about to begin. Here, we provide an overview of the state of molluscan mitochondrial genomics, highlight a few of the discoveries from this research, outline the promise of broadening this dataset, describe upcoming projects to sequence whole mollusk nuclear genomes, and challenge the community to prepare for making the best use of these data.

  4. Biobanks for Genomics and Genomics for Biobanks

    PubMed Central

    Ducournau, Pascal; Gourraud, Pierre-Antoine; Pontille, David

    2003-01-01

    Biobanks include biological samples and attached databases. Human biobanks occur in research, technological development and medical activities. Population genomics is highly dependent on the availability of large biobanks. Ethical issues must be considered: protecting the rights of those people whose samples or data are in biobanks (information, autonomy, confidentiality, protection of private life), assuring the non-commercial use of human body elements and the optimal use of samples and data. They balance other issues, such as protecting the rights of researchers and companies, allowing long-term use of biobanks while detailed information on future uses is not available. At the level of populations, the traditional form of informed consent is challenged. Other dimensions relate to the rights of a group as such, in addition to individual rights. Conditions of return of results and/or benefit to a population need to be defined. With ‘large-scale biobanking’ a marked trend in genomics, new societal dimensions appear, regarding communication, debate, regulation, societal control and valorization of such large biobanks. Exploring how genomics can help health sector biobanks to become more rationally constituted and exploited is an interesting perspective. For example, evaluating how genomic approaches can help in optimizing haematopoietic stem cell donor registries using new markers and high-throughput techniques to increase immunogenetic variability in such registries is a challenge currently being addressed. Ethical issues in such contexts are important, as not only individual decisions or projects are concerned, but also national policies in the international arena and organization of democratic debate about science, medicine and society. PMID:18629026

  5. How the genome folds

    NASA Astrophysics Data System (ADS)

    Lieberman Aiden, Erez

    2012-02-01

    I describe Hi-C, a novel technology for probing the three-dimensional architecture of whole genomes by coupling proximity-based ligation with massively parallel sequencing. Working with collaborators at the Broad Institute and UMass Medical School, we used Hi-C to construct spatial proximity maps of the human genome at a resolution of 1Mb. These maps confirm the presence of chromosome territories and the spatial proximity of small, gene-rich chromosomes. We identified an additional level of genome organization that is characterized by the spatial segregation of open and closed chromatin to form two genome-wide compartments. At the megabase scale, the chromatin conformation is consistent with a fractal globule, a knot-free conformation that enables maximally dense packing while preserving the ability to easily fold and unfold any genomic locus. The fractal globule is distinct from the more commonly used globular equilibrium model. Our results demonstrate the power of Hi-C to map the dynamic conformations of whole genomes.

  6. Human Genome Annotation

    NASA Astrophysics Data System (ADS)

    Gerstein, Mark

    A central problem for 21st century science is annotating the human genome and making this annotation useful for the interpretation of personal genomes. My talk will focus on annotating the 99% of the genome that does not code for canonical genes, concentrating on intergenic features such as structural variants (SVs), pseudogenes (protein fossils), binding sites, and novel transcribed RNAs (ncRNAs). In particular, I will describe how we identify regulatory sites and variable blocks (SVs) based on processing next-generation sequencing experiments. I will further explain how we cluster together groups of sites to create larger annotations. Next, I will discuss a comprehensive pseudogene identification pipeline, which has enabled us to identify >10K pseudogenes in the genome and analyze their distribution with respect to age, protein family, and chromosomal location. Throughout, I will try to introduce some of the computational algorithms and approaches that are required for genome annotation. Much of this work has been carried out in the framework of the ENCODE, modENCODE, and 1000 genomes projects.

  7. An archaeal genomic signature

    NASA Technical Reports Server (NTRS)

    Graham, D. E.; Overbeek, R.; Olsen, G. J.; Woese, C. R.

    2000-01-01

    Comparisons of complete genome sequences allow the most objective and comprehensive descriptions possible of a lineage's evolution. This communication uses the completed genomes from four major euryarchaeal taxa to define a genomic signature for the Euryarchaeota and, by extension, the Archaea as a whole. The signature is defined in terms of the set of protein-encoding genes found in at least two diverse members of the euryarchaeal taxa that function uniquely within the Archaea; most signature proteins have no recognizable bacterial or eukaryal homologs. By this definition, 351 clusters of signature proteins have been identified. Functions of most proteins in this signature set are currently unknown. At least 70% of the clusters that contain proteins from all the euryarchaeal genomes also have crenarchaeal homologs. This conservative set, which appears refractory to horizontal gene transfer to the Bacteria or the Eukarya, would seem to reflect the significant innovations that were unique and fundamental to the archaeal "design fabric." Genomic protein signature analysis methods may be extended to characterize the evolution of any phylogenetically defined lineage. The complete set of protein clusters for the archaeal genomic signature is presented as supplementary material (see the PNAS web site, www.pnas.org).

  8. Ebolavirus comparative genomics

    DOE PAGESBeta

    Jun, Se-Ran; Leuze, Michael R.; Nookaew, Intawat; Uberbacher, Edward C.; Land, Miriam; Zhang, Qian; Wanchai, Visanu; Chai, Juanjuan; Nielsen, Morten; Trolle, Thomas; et al

    2015-07-14

    The 2014 Ebola outbreak in West Africa is the largest documented for this virus. We examine the dynamics of this genome, comparing more than one hundred currently available ebolavirus genomes to each other and to other viral genomes. Based on oligomer frequency analysis, the family Filoviridae forms a distinct group from all other sequenced viral genomes. All filovirus genomes sequenced to date encode proteins with similar functions and gene order, although there is considerable divergence in sequences between the three genera Ebolavirus, Cuevavirus, and Marburgvirus within the family Filoviridae. Whereas all ebolavirus genomes are quite similar (multiple sequences of themore » same strain are often identical), variation is most common in the intergenic regions and within specific areas of the genes encoding the glycoprotein (GP), nucleoprotein (NP), and polymerase (L). We predict regions that could contain epitope-binding sites, which might be good vaccine targets. In conclusion, this information, combined with glycosylation sites and experimentally determined epitopes, can identify the most promising regions for the development of therapeutic strategies.« less

  9. Barley Genomics: An Overview

    PubMed Central

    Sreenivasulu, Nese; Graner, Andreas; Wobus, Ulrich

    2008-01-01

    Barley (Hordeum vulgare), first domesticated in the Near East, is a well-studied crop in terms of genetics, genomics, and breeding and qualifies as a model plant for Triticeae research. Recent advances made in barley genomics mainly include the following: (i) rapid accumulation of EST sequence data, (ii) growing number of studies on transcriptome, proteome, and metabolome, (iii) new modeling techniques, (iv) availability of genome-wide knockout collections as well as efficient transformation techniques, and (v) the recently started genome sequencing effort. These developments pave the way for a comprehensive functional analysis and understanding of gene expression networks linked to agronomically important traits. Here, we selectively review important technological developments in barley genomics and related fields and discuss the relevance for understanding genotype-phenotype relationships by using approaches such as genetical genomics and association studies. High-throughput genotyping platforms that have recently become available will allow the construction of high-density genetic maps that will further promote marker-assisted selection as well as physical map construction. Systems biology approaches will further enhance our knowledge and largely increase our abilities to design refined breeding strategies on the basis of detailed molecular physiological knowledge. PMID:18382615

  10. A Review on Genomics APIs

    PubMed Central

    Swaminathan, Rajeswari; Huang, Yungui; Moosavinasab, Soheil; Buckley, Ronald; Bartlett, Christopher W.; Lin, Simon M.

    2015-01-01

    The constant improvement and falling prices of whole human genome Next Generation Sequencing (NGS) has resulted in rapid adoption of genomic information at both clinics and research institutions. Considered together, the complexity of genomics data, due to its large volume and diversity along with the need for genomic data sharing, has resulted in the creation of Application Programming Interface (API) for secure, modular, interoperable access to genomic data from different applications, platforms, and even organizations. The Genomics APIs are a set of special protocols that assist software developers in dealing with multiple genomic data sources for building seamless, interoperable applications leading to the advancement of both genomic and clinical research. These APIs help define a standard for retrieval of genomic data from multiple sources as well as to better package genomic information for integration with Electronic Health Records. This review covers three currently available Genomics APIs: a) Google Genomics, b) SMART Genomics, and c) 23andMe. The functionalities, reference implementations (if available) and authentication protocols of each API are reviewed. A comparative analysis of the different features across the three APIs is provided in the Discussion section. Though Genomics APIs are still under active development and have yet to reach widespread adoption, they hold the promise to make building of complicated genomics applications easier with downstream constructive effects on healthcare. PMID:26702340

  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. GenomeVista

    SciTech Connect

    Poliakov, Alexander; Couronne, Olivier

    2002-11-04

    Aligning large vertebrate genomes that are structurally complex poses a variety of problems not encountered on smaller scales. Such genomes are rich in repetitive elements and contain multiple segmental duplications, which increases the difficulty of identifying true orthologous SNA segments in alignments. The sizes of the sequences make many alignment algorithms designed for comparing single proteins extremely inefficient when processing large genomic intervals. We integrated both local and global alignment tools and developed a suite of programs for automatically aligning large vertebrate genomes and identifying conserved non-coding regions in the alignments. Our method uses the BLAT local alignment program to find anchors on the base genome to identify regions of possible homology for a query sequence. These regions are postprocessed to find the best candidates which are then globally aligned using the AVID global alignment program. In the last step conserved non-coding segments are identified using VISTA. Our methods are fast and the resulting alignments exhibit a high degree of sensitivity, covering more than 90% of known coding exons in the human genome. The GenomeVISTA software is a suite of Perl programs that is built on a MySQL database platform. The scheduler gets control data from the database, builds a queve of jobs, and dispatches them to a PC cluster for execution. The main program, running on each node of the cluster, processes individual sequences. A Perl library acts as an interface between the database and the above programs. The use of a separate library allows the programs to function independently of the database schema. The library also improves on the standard Perl MySQL database interfere package by providing auto-reconnect functionality and improved error handling.

  13. GenomeVista

    2002-11-04

    Aligning large vertebrate genomes that are structurally complex poses a variety of problems not encountered on smaller scales. Such genomes are rich in repetitive elements and contain multiple segmental duplications, which increases the difficulty of identifying true orthologous SNA segments in alignments. The sizes of the sequences make many alignment algorithms designed for comparing single proteins extremely inefficient when processing large genomic intervals. We integrated both local and global alignment tools and developed a suitemore » of programs for automatically aligning large vertebrate genomes and identifying conserved non-coding regions in the alignments. Our method uses the BLAT local alignment program to find anchors on the base genome to identify regions of possible homology for a query sequence. These regions are postprocessed to find the best candidates which are then globally aligned using the AVID global alignment program. In the last step conserved non-coding segments are identified using VISTA. Our methods are fast and the resulting alignments exhibit a high degree of sensitivity, covering more than 90% of known coding exons in the human genome. The GenomeVISTA software is a suite of Perl programs that is built on a MySQL database platform. The scheduler gets control data from the database, builds a queve of jobs, and dispatches them to a PC cluster for execution. The main program, running on each node of the cluster, processes individual sequences. A Perl library acts as an interface between the database and the above programs. The use of a separate library allows the programs to function independently of the database schema. The library also improves on the standard Perl MySQL database interfere package by providing auto-reconnect functionality and improved error handling.« less

  14. Genomes to Proteomes

    SciTech Connect

    Panisko, Ellen A.; Grigoriev, Igor; Daly, Don S.; Webb-Robertson, Bobbie-Jo; Baker, Scott E.

    2009-03-01

    Biologists are awash with genomic sequence data. In large part, this is due to the rapid acceleration in the generation of DNA sequence that occurred as public and private research institutes raced to sequence the human genome. In parallel with the large human genome effort, mostly smaller genomes of other important model organisms were sequenced. Projects following on these initial efforts have made use of technological advances and the DNA sequencing infrastructure that was built for the human and other organism genome projects. As a result, the genome sequences of many organisms are available in high quality draft form. While in many ways this is good news, there are limitations to the biological insights that can be gleaned from DNA sequences alone; genome sequences offer only a bird's eye view of the biological processes endemic to an organism or community. Fortunately, the genome sequences now being produced at such a high rate can serve as the foundation for other global experimental platforms such as proteomics. Proteomic methods offer a snapshot of the proteins present at a point in time for a given biological sample. Current global proteomics methods combine enzymatic digestion, separations, mass spectrometry and database searching for peptide identification. One key aspect of proteomics is the prediction of peptide sequences from mass spectrometry data. Global proteomic analysis uses computational matching of experimental mass spectra with predicted spectra based on databases of gene models that are often generated computationally. Thus, the quality of gene models predicted from a genome sequence is crucial in the generation of high quality peptide identifications. Once peptides are identified they can be assigned to their parent protein. Proteins identified as expressed in a given experiment are most useful when compared to other expressed proteins in a larger biological context or biochemical pathway. In this chapter we will discuss the automatic

  15. Genome position specific priors for genomic prediction

    PubMed Central

    2012-01-01

    Background The accuracy of genomic prediction is highly dependent on the size of the reference population. For small populations, including information from other populations could improve this accuracy. The usual strategy is to pool data from different populations; however, this has not proven as successful as hoped for with distantly related breeds. BayesRS is a novel approach to share information across populations for genomic predictions. The approach allows information to be captured even where the phase of SNP alleles and casuative mutation alleles are reversed across populations, or the actual casuative mutation is different between the populations but affects the same gene. Proportions of a four-distribution mixture for SNP effects in segments of fixed size along the genome are derived from one population and set as location specific prior proportions of distributions of SNP effects for the target population. The model was tested using dairy cattle populations of different breeds: 540 Australian Jersey bulls, 2297 Australian Holstein bulls and 5214 Nordic Holstein bulls. The traits studied were protein-, fat- and milk yield. Genotypic data was Illumina 777K SNPs, real or imputed. Results Results showed an increase in accuracy of up to 3.5% for the Jersey population when using BayesRS with a prior derived from Australian Holstein compared to a model without location specific priors. The increase in accuracy was however lower than was achieved when reference populations were combined to estimate SNP effects, except in the case of fat yield. The small size of the Jersey validation set meant that these improvements in accuracy were not significant using a Hotelling-Williams t-test at the 5% level. An increase in accuracy of 1-2% for all traits was observed in the Australian Holstein population when using a prior derived from the Nordic Holstein population compared to using no prior information. These improvements were significant (P<0.05) using the Hotelling

  16. Berkeley Quantitative Genome Browser

    SciTech Connect

    Hechmer, Aaron

    2008-02-29

    The Berkeley Quantitative Genome Browser provides graphical browsing functionality for genomic data organized, at a minimum, by sequence and position. While supporting the annotation browsing features typical of many other genomic browsers, additional emphasis is placed on viewing and utilizing quantitative data. Data may be read from GFF, SGR, FASTA or any column delimited format. Once the data has been read into the browser's buffer, it may be searched. filtered or subjected to mathematical transformation. The browser also supplies some graphical design manipulation functionality geared towards preparing figures for presentations or publication. A plug-in mechanism enables development outside the core functionality that adds more advanced or esoteric analysis capabilities. BBrowse's development and distribution is open-source and has been built to run on Linux, OSX and MS Windows operating systems.

  17. Genomics, health, and society.

    PubMed

    Chan, Chee Khoon

    2002-01-01

    On June 27, 2001, the World Health Organization conducted hearings in Geneva for a Special Report on Genomics & Health. Initially intended as a document to address the ethical, legal, and social implications of the gathering genomics resolution (ELSI), the terms of reference of the report were significantly modified to give primary emphasis to a scientific and technological assessment of the implications of genomics for human health. The Citizens' Health Initiative, one of two NGOs invited to make submissions at these consultations, suggested that no less important than the scientific and technical assessment was a perspective which gave due attention to the social context and political economy of scientific/technological development and its deployment. The article below touches upon neglected health priorities of poor countries, intellectual property rights and patents, risk management, insurance and discrimination, and predictive (prenatal) testing, reproductive choice, and eugenics. PMID:17208760

  18. Berkeley Quantitative Genome Browser

    2008-02-29

    The Berkeley Quantitative Genome Browser provides graphical browsing functionality for genomic data organized, at a minimum, by sequence and position. While supporting the annotation browsing features typical of many other genomic browsers, additional emphasis is placed on viewing and utilizing quantitative data. Data may be read from GFF, SGR, FASTA or any column delimited format. Once the data has been read into the browser's buffer, it may be searched. filtered or subjected to mathematical transformation.more » The browser also supplies some graphical design manipulation functionality geared towards preparing figures for presentations or publication. A plug-in mechanism enables development outside the core functionality that adds more advanced or esoteric analysis capabilities. BBrowse's development and distribution is open-source and has been built to run on Linux, OSX and MS Windows operating systems.« less

  19. Genomics for Weed Science

    PubMed Central

    Horvath, David

    2010-01-01

    Numerous genomic-based studies have provided insight to the physiological and evolutionary processes involved in developmental and environmental processes of model plants such as arabidopsis and rice. However, far fewer efforts have been attempted to use genomic resources to study physiological and evolutionary processes of weedy plants. Genomics-based tools such as extensive EST databases and microarrays have been developed for a limited number of weedy species, although application of information and resources developed for model plants and crops are possible and have been exploited. These tools have just begun to provide insights into the response of these weeds to herbivore and pathogen attack, survival of extreme environmental conditions, and interaction with crops. The potential of these tools to illuminate mechanisms controlling the traits that allow weeds to invade novel habitats, survive extreme environments, and that make weeds difficult to eradicate have potential for both improving crops and developing novel methods to control weeds. PMID:20808523

  20. SINGLE CELL GENOME SEQUENCING

    PubMed Central

    Yilmaz, Suzan; Singh, Anup K.

    2011-01-01

    Whole genome amplification and next-generation sequencing of single cells has become a powerful approach for studying uncultivated microorganisms that represent 90–99 % of all environmental microbes. Single cell sequencing enables not only the identification of microbes but also linking of functions to species, a feat not achievable by metagenomic techniques. Moreover, it allows the analysis of low abundance species that may be missed in community-based analyses. It has also proved very useful in complementing metagenomics in the assembly and binning of single genomes. With the advent of drastically cheaper and higher throughput sequencing technologies, it is expected that single cell sequencing will become a standard tool in studying the genome and transcriptome of microbial communities. PMID:22154471

  1. Genomic Southern blot analysis.

    PubMed

    Gebbie, Leigh

    2014-01-01

    This chapter describes a detailed protocol for genomic Southern blot analysis which can be used to detect transgene or endogenous gene sequences in cereal genomes. The protocol follows a standard approach that has been shown to generate high-quality results: size fractionation of genomic DNA; capillary transfer to a nylon membrane; hybridization with a digoxigenin-labelled probe; and detection using a chemiluminescent-based system. High sensitivity and limited background are key to successful Southern blots. The critical steps in this protocol are complete digestion of the right quantity of DNA, careful handling of the membrane to avoid unnecessary background, and optimization of probe concentration and temperatures during the hybridization step. Detailed instructions on how to successfully master these techniques are provided. PMID:24243203

  2. Genomics of Volvocine Algae

    PubMed Central

    Umen, James G.; Olson, Bradley J.S.C.

    2015-01-01

    Volvocine algae are a group of chlorophytes that together comprise a unique model for evolutionary and developmental biology. The species Chlamydomonas reinhardtii and Volvox carteri represent extremes in morphological diversity within the Volvocine clade. Chlamydomonas is unicellular and reflects the ancestral state of the group, while Volvox is multicellular and has evolved numerous innovations including germ-soma differentiation, sexual dimorphism, and complex morphogenetic patterning. The Chlamydomonas genome sequence has shed light on several areas of eukaryotic cell biology, metabolism and evolution, while the Volvox genome sequence has enabled a comparison with Chlamydomonas that reveals some of the underlying changes that enabled its transition to multicellularity, but also underscores the subtlety of this transition. Many of the tools and resources are in place to further develop Volvocine algae as a model for evolutionary genomics. PMID:25883411

  3. Genomic medicine and neurology.

    PubMed

    Vance, Jeffery M; Tekin, Demet

    2011-04-01

    The application of genetics to the understanding of neurology has been highly successful over the past several decades. During the past 10 years, tools were developed to begin genetic investigations into more common disorders such as Alzheimer disease, multiple sclerosis, autism, and Parkinson disease. The era of genomic medicine now has begun and will have an increasing effect on the daily care of common neurologic diseases. Thus it is important for neurologists to have a basic understanding of genomic medicine and how it differs from the traditional clinical genetics of the past. This article provides some basic information about genomic medicine and pharmacogenetics in neurology to help neurologists to begin to adopt these principles into their practice. PMID:22810818

  4. Genomic Imprinting in Mammals

    PubMed Central

    Barlow, Denise P.

    2014-01-01

    Genomic imprinting affects a subset of genes in mammals and results in a monoallelic, parental-specific expression pattern. Most of these genes are located in clusters that are regulated through the use of insulators or long noncoding RNAs (lncRNAs). To distinguish the parental alleles, imprinted genes are epigenetically marked in gametes at imprinting control elements through the use of DNA methylation at the very least. Imprinted gene expression is subsequently conferred through lncRNAs, histone modifications, insulators, and higher-order chromatin structure. Such imprints are maintained after fertilization through these mechanisms despite extensive reprogramming of the mammalian genome. Genomic imprinting is an excellent model for understanding mammalian epigenetic regulation. PMID:24492710

  5. Resequencing rice genomes: an emerging new era of rice genomics.

    PubMed

    Huang, Xuehui; Lu, Tingting; Han, Bin

    2013-04-01

    Rice is a model system for crop genomics studies. Much of the early work on rice genomics focused on analyzing genome-wide genetic variation to further understand rice gene functions in agronomic traits and to generate data and resources for rice research. The advent of next-generation high-throughput DNA sequencing technologies and the completion of high-quality reference genome sequences have enabled the development of sequencing-based genotyping and genome-wide association studies (GWAS) that have significantly advanced rice genetics research. This has led to the emergence of a new era of rice genomics aimed at bridging the knowledge gap between genotype and phenotype in rice. These technologies have also led to pyramid breeding through genomics-assisted selection, which will be useful in breeding elite varieties suitable for sustainable agriculture. Here, we review the recent advances in rice genomics and discuss the future of this line of research. PMID:23295340

  6. Brief Guide to Genomics: DNA, Genes and Genomes

    MedlinePlus

    ... guía de genómica A Brief Guide to Genomics DNA, Genes and Genomes Deoxyribonucleic acid (DNA) is the ... and lead to a disease such as cancer. DNA Sequencing Sequencing simply means determining the exact order ...

  7. Haemonchus contortus: Genome Structure, Organization and Comparative Genomics.

    PubMed

    Laing, R; Martinelli, A; Tracey, A; Holroyd, N; Gilleard, J S; Cotton, J A

    2016-01-01

    One of the first genome sequencing projects for a parasitic nematode was that for Haemonchus contortus. The open access data from the Wellcome Trust Sanger Institute provided a valuable early resource for the research community, particularly for the identification of specific genes and genetic markers. Later, a second sequencing project was initiated by the University of Melbourne, and the two draft genome sequences for H. contortus were published back-to-back in 2013. There is a pressing need for long-range genomic information for genetic mapping, population genetics and functional genomic studies, so we are continuing to improve the Wellcome Trust Sanger Institute assembly to provide a finished reference genome for H. contortus. This review describes this process, compares the H. contortus genome assemblies with draft genomes from other members of the strongylid group and discusses future directions for parasite genomics using the H. contortus model. PMID:27238013

  8. Ebolavirus comparative genomics

    PubMed Central

    Jun, Se-Ran; Leuze, Michael R.; Nookaew, Intawat; Uberbacher, Edward C.; Land, Miriam; Zhang, Qian; Wanchai, Visanu; Chai, Juanjuan; Nielsen, Morten; Trolle, Thomas; Lund, Ole; Buzard, Gregory S.; Pedersen, Thomas D.; Wassenaar, Trudy M.; Ussery, David W.

    2015-01-01

    The 2014 Ebola outbreak in West Africa is the largest documented for this virus. To examine the dynamics of this genome, we compare more than 100 currently available ebolavirus genomes to each other and to other viral genomes. Based on oligomer frequency analysis, the family Filoviridae forms a distinct group from all other sequenced viral genomes. All filovirus genomes sequenced to date encode proteins with similar functions and gene order, although there is considerable divergence in sequences between the three genera Ebolavirus, Cuevavirus and Marburgvirus within the family Filoviridae. Whereas all ebolavirus genomes are quite similar (multiple sequences of the same strain are often identical), variation is most common in the intergenic regions and within specific areas of the genes encoding the glycoprotein (GP), nucleoprotein (NP) and polymerase (L). We predict regions that could contain epitope-binding sites, which might be good vaccine targets. This information, combined with glycosylation sites and experimentally determined epitopes, can identify the most promising regions for the development of therapeutic strategies. This manuscript has been authored by UT-Battelle, LLC under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe-public-access-plan). PMID:26175035

  9. Ebolavirus comparative genomics.

    PubMed

    Jun, Se-Ran; Leuze, Michael R; Nookaew, Intawat; Uberbacher, Edward C; Land, Miriam; Zhang, Qian; Wanchai, Visanu; Chai, Juanjuan; Nielsen, Morten; Trolle, Thomas; Lund, Ole; Buzard, Gregory S; Pedersen, Thomas D; Wassenaar, Trudy M; Ussery, David W

    2015-09-01

    The 2014 Ebola outbreak in West Africa is the largest documented for this virus. To examine the dynamics of this genome, we compare more than 100 currently available ebolavirus genomes to each other and to other viral genomes. Based on oligomer frequency analysis, the family Filoviridae forms a distinct group from all other sequenced viral genomes. All filovirus genomes sequenced to date encode proteins with similar functions and gene order, although there is considerable divergence in sequences between the three genera Ebolavirus, Cuevavirus and Marburgvirus within the family Filoviridae. Whereas all ebolavirus genomes are quite similar (multiple sequences of the same strain are often identical), variation is most common in the intergenic regions and within specific areas of the genes encoding the glycoprotein (GP), nucleoprotein (NP) and polymerase (L). We predict regions that could contain epitope-binding sites, which might be good vaccine targets. This information, combined with glycosylation sites and experimentally determined epitopes, can identify the most promising regions for the development of therapeutic strategies.This manuscript has been authored by UT-Battelle, LLC under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe-public-access-plan). PMID:26175035

  10. Genome Size and Species Diversification

    PubMed Central

    2010-01-01

    Theoretically, there are reasons to believe that large genome size should favour speciation. Several major factors contributing to genome size, such as duplications and transposable element activity have been proposed to facilitate the formation of new species. However, it is also possible that small genome size promotes speciation. For example, selection for genome reduction may be resolved in different ways in incipient species, leading to incompatibilities. Mutations and chromosomal rearrangements may also be more stably inherited in smaller genomes. Here I review the following lines of empirical evidence bearing on this question: (i) Correlations between genome size and species richness of taxa are often negative. (ii) Fossil evidence in lungfish shows that the accumulation of DNA in the genomes of this group coincided with a reduction in species diversity. (iii) Estimates of speciation interval in mammals correlate positively with genome size. (iv) Genome reductions are inferred at the base of particular species radiations and genome expansions at the base of others. (v) Insect clades that have been increasing in diversity up to the present have smaller genomes than clades that have remained stable or have decreased in diversity. The general pattern emerging from these observations is that higher diversification rates are generally found in small-genome taxa. Since diversification rates are the net effect of speciation and extinction, large genomes may thus either constrain speciation rate, increase extinction rate, or both. I argue that some of the cited examples are unlikely to be explained by extinction alone. PMID:22140283

  11. The cancer genome

    PubMed Central

    Stratton, Michael R.; Campbell, Peter J.; Futreal, P. Andrew

    2010-01-01

    All cancers arise as a result of changes that have occurred in the DNA sequence of the genomes of cancer cells. Over the past quarter of a century much has been learnt about these mutations and the abnormal genes that operate in human cancers. We are now, however, moving into an era in which it will be possible to obtain the complete DNA sequence of large numbers of cancer genomes. These studies will provide us with a detailed and comprehensive perspective on how individual cancers have developed. PMID:19360079

  12. Methanococcus jannaschii genome: revisited

    NASA Technical Reports Server (NTRS)

    Kyrpides, N. C.; Olsen, G. J.; Klenk, H. P.; White, O.; Woese, C. R.

    1996-01-01

    Analysis of genomic sequences is necessarily an ongoing process. Initial gene assignments tend (wisely) to be on the conservative side (Venter, 1996). The analysis of the genome then grows in an iterative fashion as additional data and more sophisticated algorithms are brought to bear on the data. The present report is an emendation of the original gene list of Methanococcus jannaschii (Bult et al., 1996). By using a somewhat more updated database and more relaxed (and operator-intensive) pattern matching methods, we were able to add significantly to, and in a few cases amend, the gene identification table originally published by Bult et al. (1996).

  13. Genomic standards consortium projects.

    PubMed

    Field, Dawn; Sterk, Peter; Kottmann, Renzo; De Smet, J Wim; Amaral-Zettler, Linda; Cochrane, Guy; Cole, James R; Davies, Neil; Dawyndt, Peter; Garrity, George M; Gilbert, Jack A; Glöckner, Frank Oliver; Hirschman, Lynette; Klenk, Hans-Peter; Knight, Rob; Kyrpides, Nikos; Meyer, Folker; Karsch-Mizrachi, Ilene; Morrison, Norman; Robbins, Robert; San Gil, Inigo; Sansone, Susanna; Schriml, Lynn; Tatusova, Tatiana; Ussery, Dave; Yilmaz, Pelin; White, Owen; Wooley, John; Caporaso, Gregory

    2014-06-15

    The Genomic Standards Consortium (GSC) is an open-membership community that was founded in 2005 to work towards the development, implementation and harmonization of standards in the field of genomics. Starting with the defined task of establishing a minimal set of descriptions the GSC has evolved into an active standards-setting body that currently has 18 ongoing projects, with additional projects regularly proposed from within and outside the GSC. Here we describe our recently enacted policy for proposing new activities that are intended to be taken on by the GSC, along with the template for proposing such new activities. PMID:25197446

  14. The Brachypodium genome sequence: a resource for oat genomics research

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Oat (Avena sativa) is an important cereal crop used as both an animal feed and for human consumption. Genetic and genomic research on oat is hindered because it is hexaploid and possesses a large (13 Gb) genome. Diploid Avena relatives have been employed for genetic and genomic studies, but only mod...

  15. Tick Genomics: The Ixodes genome project and beyond

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ticks and mites (subphylum Chelicerata; subclass Acari) are important pests of animals and plants worldwide. The Ixodes scapularis (black-legged tick) genome sequencing project marks the beginning of the genomics era for the field of acarology. This project is the first to sequence the genome of a...

  16. Multiplexed Fragaria Chloroplast Genome Sequencing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A method to sequence multiple chloroplast genomes that uses the sequencing depth of ultra high throughput sequencing technologies was recently described. Sequencing complete chloroplast genomes can resolve phylogenetic relationships at low taxonomic levels and identify point mutations and indels tha...

  17. The diversity of fungal genome.

    PubMed

    Mohanta, Tapan Kumar; Bae, Hanhong

    2015-01-01

    The genome size of an organism varies from species to species. The C-value paradox enigma is a very complex puzzle with regards to vast diversity in genome sizes in eukaryotes. Here we reported the detailed genomic information of 172 fungal species among different fungal genomes and found that fungal genomes are very diverse in nature. In fungi, the diversity of genomes varies from 8.97 Mb to 177.57 Mb. The average genome sizes of Ascomycota and Basidiomycota fungi are 36.91 and 46.48 Mb respectively. But higher genome size is observed in Oomycota (74.85 Mb) species, a lineage of fungus-like eukaryotic microorganisms. The average coding genes of Oomycota species are almost doubled than that of Acomycota and Basidiomycota fungus. PMID:25866485

  18. Company profile: Complete Genomics Inc.

    PubMed

    Reid, Clifford

    2011-02-01

    Complete Genomics Inc. is a life sciences company that focuses on complete human genome sequencing. It is taking a completely different approach to DNA sequencing than other companies in the industry. Rather than building a general-purpose platform for sequencing all organisms and all applications, it has focused on a single application - complete human genome sequencing. The company's Complete Genomics Analysis Platform (CGA™ Platform) comprises an integrated package of biochemistry, instrumentation and software that sequences human genomes at the highest quality, lowest cost and largest scale available. Complete Genomics offers a turnkey service that enables customers to outsource their human genome sequencing to the company's genome sequencing center in Mountain View, CA, USA. Customers send in their DNA samples, the company does all the library preparation, DNA sequencing, assembly and variant analysis, and customers receive research-ready data that they can use for biological discovery. PMID:21345140

  19. On genomics, kin, and privacy

    PubMed Central

    Telenti, Amalio; Ayday, Erman; Hubaux, Jean Pierre

    2014-01-01

    The storage of greater numbers of exomes or genomes raises the question of loss of privacy for the individual and for families if genomic data are not properly protected. Access to genome data may result from a personal decision to disclose, or from gaps in protection. In either case, revealing genome data has consequences beyond the individual, as it compromises the privacy of family members. Increasing availability of genome data linked or linkable to metadata through online social networks and services adds one additional layer of complexity to the protection of genome privacy.  The field of computer science and information technology offers solutions to secure genomic data so that individuals, medical personnel or researchers can access only the subset of genomic information required for healthcare or dedicated studies. PMID:25254097

  20. National Human Genome Research Institute

    MedlinePlus

    ... for Patient Care Education All About the Human Genome Project Fact Sheets Genetic Education Resources for Teachers ... Education Kit Online Genetics Education Resources Smithsonian NHGRI Genome Exhibition Talking Glossary: English Talking Glossary: Español Issues ...

  1. Importance of anchor genomes for any plant genome project

    PubMed Central

    Messing, Joachim; Llaca, Victor

    1998-01-01

    Progress in agricultural and environmental technologies is hampered by a slower rate of gene discovery in plants than animals. The vast pool of genes in plants, however, will be an important resource for insertion of genes, via biotechnological procedures, into an array of plants, generating unique germ plasms not achievable by conventional breeding. It just became clear that genomes of grasses have evolved in a manner analogous to Lego blocks. Large chromosome segments have been reshuffled and stuffer pieces added between genes. Although some genomes have become very large, the genome with the fewest stuffer pieces, the rice genome, is the Rosetta Stone of all the bigger grass genomes. This means that sequencing the rice genome as anchor genome of the grasses will provide instantaneous access to the same genes in the same relative physical position in other grasses (e.g., corn and wheat), without the need to sequence each of these genomes independently. (i) The sequencing of the entire genome of rice as anchor genome for the grasses will accelerate plant gene discovery in many important crops (e.g., corn, wheat, and rice) by several orders of magnitudes and reduce research and development costs for government and industry at a faster pace. (ii) Costs for sequencing entire genomes have come down significantly. Because of its size, rice is only 12% of the human or the corn genome, and technology improvements by the human genome project are completely transferable, translating in another 50% reduction of the costs. (iii) The physical mapping of the rice genome by a group of Japanese researchers provides a jump start for sequencing the genome and forming an international consortium. Otherwise, other countries would do it alone and own proprietary positions. PMID:9482827

  2. Genomics in Cardiovascular Disease

    PubMed Central

    Roberts, Robert; Marian, A.J.; Dandona, Sonny; Stewart, Alexandre F.R.

    2013-01-01

    A paradigm shift towards biology occurred in the 1990’s subsequently catalyzed by the sequencing of the human genome in 2000. The cost of DNA sequencing has gone from millions to thousands of dollars with sequencing of one’s entire genome costing only $1,000. Rapid DNA sequencing is being embraced for single gene disorders, particularly for sporadic cases and those from small families. Transmission of lethal genes such as associated with Huntington’s disease can, through in-vitro fertilization, avoid passing it on to one’s offspring. DNA sequencing will meet the challenge of elucidating the genetic predisposition for common polygenic diseases, especially in determining the function of the novel common genetic risk variants and identifying the rare variants, which may also partially ascertain the source of the missing heritability. The challenge for DNA sequencing remains great, despite human genome sequences being 99.5% identical, the 3 million single nucleotide polymorphisms (SNPs) responsible for most of the unique features add up to 60 new mutations per person which, for 7 billion people, is 420 billion mutations. It is claimed that DNA sequencing has increased 10,000 fold while information storage and retrieval only 16 fold. The physician and health user will be challenged by the convergence of two major trends, whole genome sequencing and the storage/retrieval and integration of the data. PMID:23524054

  3. Poster: the macaque genome.

    PubMed

    2007-04-13

    The rhesus macaque (Macaca mulatta) facilitates an extraordinary range of biomedical and basic research, and the publication of the genome only makes it a more powerful model for studies of human disease; moreover, the macaque's position relative to humans and chimpanzees affords the opportunity to learn about the processes that have shaped the last 25 million years of primate evolution. To allow users to explore these themes of the macaque genome, Science has created a special interactive version of the poster published in the print edition of the 13 April 2007 issue. The interactive version includes additional text and exploration, as well as embedded video featuring seven scientists discussing the importance of the macaque and its genome sequence in studies of biomedicine and evolution. We have also created an accompanying teaching resource, including a lesson plan aimed at teachers of advanced high school life science students, for exploring what a comparison of the macaque and human genomes can tell us about human biology and evolution. These items are free to all site visitors. PMID:17431172

  4. (Genomic variation in maize)

    SciTech Connect

    Rivin, C.J.

    1991-01-01

    These studies have sought to learn how different DNA sequences and sequence arrangements contribute to genome plasticity in maize. We describe quantitative variation among maize inbred lines for tandemly arrayed and dispersed repeated DNA sequences and gene families, and qualitative variation for sequences homologous to the Mutator family of transposons. The potential of these sequences to undergo unequal crossing over, non-allelic (ectopic) recombination and transposition makes them a source of genome instability. We have found examples of rapid genomic change involving these sequences in Fl hybrids, tissue culture cells and regenerated plants. We describe the repetitive portion of the maize genome as composed primarily of sequences that vary markedly in copy number among different genetic stocks. The most highly variable is the 185 bp repeat associated with the heterochromatic chromosome knobs. Even in lines without visible knobs, there is a considerable quantity of tandemly arrayed repeats. We also found a high degree of variability for the tandemly arrayed 5S and ribosomal DNA repeats. While such variation might be expected as the result of unequal cross-over, we were surprised to find considerable variation among lower copy number, dispersed repeats as well. One highly repeated sequence that showed a complex tandem and dispersed arrangement stood out as showing no detectable variability among the maize lines. In striking contrast to the variability seen between the inbred stocks, individuals within a stock were indistinguishable with regard to their repeated sequence multiplicities.

  5. Better chocolate through genomics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Theobroma cacao, the cacao or chocolate tree, is a tropical understory tree whose seeds are used to make chocolate. And like any important crop, cacao is the subject of much research. On September 15, 2010, scientists publicly released a preliminary sequence of the cacao genome--which contains all o...

  6. The Nostoc punctiforme Genome

    SciTech Connect

    John C. Meeks

    2001-12-31

    Nostoc punctiforme is a filamentous cyanobacterium with extensive phenotypic characteristics and a relatively large genome, approaching 10 Mb. The phenotypic characteristics include a photoautotrophic, diazotrophic mode of growth, but N. punctiforme is also facultatively heterotrophic; its vegetative cells have multiple development alternatives, including terminal differentiation into nitrogen-fixing heterocysts and transient differentiation into spore-like akinetes or motile filaments called hormogonia; and N. punctiforme has broad symbiotic competence with fungi and terrestrial plants, including bryophytes, gymnosperms and an angiosperm. The shotgun-sequencing phase of the N. punctiforme strain ATCC 29133 genome has been completed by the Joint Genome Institute. Annotation of an 8.9 Mb database yielded 7432 open reading frames, 45% of which encode proteins with known or probable known function and 29% of which are unique to N. punctiforme. Comparative analysis of the sequence indicates a genome that is highly plastic and in a state of flux, with numerous insertion sequences and multilocus repeats, as well as genes encoding transposases and DNA modification enzymes. The sequence also reveals the presence of genes encoding putative proteins that collectively define almost all characteristics of cyanobacteria as a group. N. punctiforme has an extensive potential to sense and respond to environmental signals as reflected by the presence of more than 400 genes encoding sensor protein kinases, response regulators and other transcriptional factors. The signal transduction systems and any of the large number of unique genes may play essential roles in the cell differentiation and symbiotic interaction properties of N. punctiforme.

  7. The human genome project.

    PubMed Central

    Olson, M V

    1993-01-01

    The Human Genome Project in the United States is now well underway. Its programmatic direction was largely set by a National Research Council report issued in 1988. The broad framework supplied by this report has survived almost unchanged despite an upheaval in the technology of genome analysis. This upheaval has primarily affected physical and genetic mapping, the two dominant activities in the present phase of the project. Advances in mapping techniques have allowed good progress toward the specific goals of the project and are also providing strong corollary benefits throughout biomedical research. Actual DNA sequencing of the genomes of the human and model organisms is still at an early stage. There has been little progress in the intrinsic efficiency of DNA-sequence determination. However, refinements in experimental protocols, instrumentation, and project management have made it practical to acquire sequence data on an enlarged scale. It is also increasingly apparent that DNA-sequence data provide a potent means of relating knowledge gained from the study of model organisms to human biology. There is as yet little indication that the infusion of technology from outside biology into the Human Genome Project has been effectively stimulated. Opportunities in this area remain large, posing substantial technical and policy challenges. PMID:8506271

  8. Genetics, genomics and fertility

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In order to enhance the sustainability of dairy businesses, new management tools are needed to increase the fertility of dairy cattle. Genomic selection has been successfully used by AI studs to screen potential sires and significantly decrease the generation interval of bulls. Buoyed by the success...

  9. Dairy genomics in application

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Implementation of genomic evaluation has caused profound changes in dairy cattle breeding. All young bulls bought by major artificial-insemination organizations now are selected based on these evaluation. Evaluation reliability can reach ~75% for yield traits, which is adequate for marketing semen o...

  10. Genomic selection in plant breeding

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genomic selection (GS) is a method to predict the genetic value of selection candidates based on the genomic estimated breeding value (GEBV) predicted from high-density markers positioned throughout the genome. Unlike marker-assisted selection, the GEBV is based on all markers including both minor ...

  11. Plant functional genomics

    NASA Astrophysics Data System (ADS)

    Holtorf, Hauke; Guitton, Marie-Christine; Reski, Ralf

    2002-04-01

    Functional genome analysis of plants has entered the high-throughput stage. The complete genome information from key species such as Arabidopsis thaliana and rice is now available and will further boost the application of a range of new technologies to functional plant gene analysis. To broadly assign functions to unknown genes, different fast and multiparallel approaches are currently used and developed. These new technologies are based on known methods but are adapted and improved to accommodate for comprehensive, large-scale gene analysis, i.e. such techniques are novel in the sense that their design allows researchers to analyse many genes at the same time and at an unprecedented pace. Such methods allow analysis of the different constituents of the cell that help to deduce gene function, namely the transcripts, proteins and metabolites. Similarly the phenotypic variations of entire mutant collections can now be analysed in a much faster and more efficient way than before. The different methodologies have developed to form their own fields within the functional genomics technological platform and are termed transcriptomics, proteomics, metabolomics and phenomics. Gene function, however, cannot solely be inferred by using only one such approach. Rather, it is only by bringing together all the information collected by different functional genomic tools that one will be able to unequivocally assign functions to unknown plant genes. This review focuses on current technical developments and their impact on the field of plant functional genomics. The lower plant Physcomitrella is introduced as a new model system for gene function analysis, owing to its high rate of homologous recombination.

  12. Thinking laterally about genomes.

    PubMed

    Ragan, Mark A

    2009-10-01

    Perhaps the most-surprising discovery of the genome era has been the extent to which prokaryotic and many eukaryotic genomes incorporate genetic material from sources other than their parent(s). Lateral genetic transfer (LGT) among bacteria was first observed about 100 years ago, and is now accepted to underlie important phenomena including the spread of antibiotic resistance and ability to degrade xenobiotics. LGT is invoked, perhaps too readily, to explain a breadth of awkward data including compositional heterogeneity of genomes, disagreement among gene-sequence trees, and mismatch between physiology and systematics. At the same time many details of LGT remain unknown or controversial, and some key questions have scarcely been asked. Here I critically review what we think we know about the existence, extent, mechanism and impact of LGT; identify important open questions; and point to research directions that hold particular promise for elucidating the role of LGT in genome evolution. Evidence for LGT in nature is not only inferential but also direct, and potential vectors are ubiquitous. Genetic material can pass between diverse habitats and be significantly altered during residency in viruses, complicating the inference of donors, In prokaryotes about twice as many genes are interrupted by LGT as are transferred intact, and about 5Short protein domains can be privileged units of transfer. Unresolved phylogenetic issues include the correct null hypothesis, and genes as units of analysis. Themes are beginning to emerge regarding the effect of LGT on cellular networks, but I show why generalization is premature. LGT can associate with radical changes in physiology and ecological niche. Better quantitative models of genome evolution are needed, and theoretical frameworks remain to be developed for some observations including chromosome assembly by LGT. PMID:20180279

  13. TUTORIAL ON NETWORK GENOMICS.

    SciTech Connect

    Forst, C.

    2001-01-01

    With the ever-increasing genomic information pouring into the databases researchers start to look for pattern in genomes. Key questions are the identification of function. In the past function was mainly understood to be assigned to a single gene isolated from other cellular components or mechanisms. Sequence comparison fo single genes and their products (proteins) as well as of intergenic space are a consequence of a well established one-gene one-function interpretation. prediction of function solely by sequence similarity searches are powerful techniques that initiated the advent of bioinformatics and computational biology. Seminal work on sequence alignment by Temple Smith and Michael Waterman [33] and sequence searches with the BLAST algorithm by Altschul et al. [2] provide essential methods for sequence based determination of function. Similar outstanding contributions to determination of function have been archived in the area of structure prediction, molecular modeling and molecular dynamics. Techniques covering ab initio and homology modeling up to biophysical interpretation of long-run molecular dynamics simulations are mentioned ehre. With the ever-increasing number of information of different genetic/genomic origin, new aspect are looked for that deviate from the single gene at a time method. Especially with the identification of surprisingly few human genes the emerging perception in the scientific community that the concept of function has to be extended to include other sequence based as well as non-sequenced based information. A schema of determination of function by different concepts is shown in Figure 1. The tutorial is comprised of the following sections: The first two sections discuss the differences between genomic and non-genomic based context information, section three will cover combined methods. Finally, section four lsits web-resources and databases. All presented approaches extensively employ comparative methods.

  14. Genome size evolution in macroparasites.

    PubMed

    Sundberg, Lotta-Riina; Pulkkinen, Katja

    2015-04-01

    Reduction in genome size has been associated not only with a parasitic lifestyle in intracellular microparasites but also in some macroparasitic insects and nematodes. We collected the available data on genome size for flatworms, annelids, nematodes and arthropods, compared those with available data for the phylogenetically closest free-living taxa and found evidence of smaller genome sizes for parasites in six of nine comparisons. Our results suggest that despite great differences in evolutionary history and life cycles, parasitism as a lifestyle promotes convergent genome size reduction in macroparasites. We discuss factors that could be associated with small genome size in parasites which require further exploration in the future. PMID:25724591

  15. Professional medical education and genomics.

    PubMed

    Demmer, Laurie A; Waggoner, Darrel J

    2014-01-01

    Genomic medicine is a relatively new concept that involves using individual patients' genomic results in their clinical care. Genetic technology has advanced swiftly over the past decade, and most providers have been left behind without an understanding of this complex field. To realize its full potential, genomic medicine must be both understood and accepted by the greater medical community. The current state of professional medical education in genomics and genomic medicine is reviewed, including ongoing plans to expand educational efforts for medical students, clinical geneticists, and nongeneticist physicians. PMID:24635717

  16. Evolution of plant genome architecture.

    PubMed

    Wendel, Jonathan F; Jackson, Scott A; Meyers, Blake C; Wing, Rod A

    2016-01-01

    We have witnessed an explosion in our understanding of the evolution and structure of plant genomes in recent years. Here, we highlight three important emergent realizations: (1) that the evolutionary history of all plant genomes contains multiple, cyclical episodes of whole-genome doubling that were followed by myriad fractionation processes; (2) that the vast majority of the variation in genome size reflects the dynamics of proliferation and loss of lineage-specific transposable elements; and (3) that various classes of small RNAs help shape genomic architecture and function. We illustrate ways in which understanding these organism-level and molecular genetic processes can be used for crop plant improvement. PMID:26926526

  17. Rice: The First Crop Genome.

    PubMed

    Jackson, Scott A

    2016-12-01

    Rice was the first sequenced crop genome, paving the way for the sequencing of additional and more complicated crop genomes. The impact that the genome sequence made on rice genetics and breeding research was immediate, as evidence by citations and DNA marker use. The impact on other crop genomes was evident too, particularly for those within the grass family. As we celebrate 10 years since the completion of the rice genome sequence, we look forward to new empowering tool sets that will further revolutionize research in rice genetics and breeding and result in varieties that will continue to feed a growing population. PMID:27003180

  18. Nongenetic functions of the genome.

    PubMed

    Bustin, Michael; Misteli, Tom

    2016-05-01

    The primary function of the genome is to store, propagate, and express the genetic information that gives rise to a cell's architectural and functional machinery. However, the genome is also a major structural component of the cell. Besides its genetic roles, the genome affects cellular functions by nongenetic means through its physical and structural properties, particularly by exerting mechanical forces and by serving as a scaffold for binding of cellular components. Major cellular processes affected by nongenetic functions of the genome include establishment of nuclear structure, signal transduction, mechanoresponses, cell migration, and vision in nocturnal animals. We discuss the concept, mechanisms, and implications of nongenetic functions of the genome. PMID:27151873

  19. Genome of Crocodilepox Virus

    PubMed Central

    Afonso, C. L.; Tulman, E. R.; Delhon, G.; Lu, Z.; Viljoen, G. J.; Wallace, D. B.; Kutish, G. F.; Rock, D. L.

    2006-01-01

    Here, we present the genome sequence, with analysis, of a poxvirus infecting Nile crocodiles (Crocodylus niloticus) (crocodilepox virus; CRV). The genome is 190,054 bp (62% G+C) and predicted to contain 173 genes encoding proteins of 53 to 1,941 amino acids. The central genomic region contains genes conserved and generally colinear with those of other chordopoxviruses (ChPVs). CRV is distinct, as the terminal 33-kbp (left) and 13-kbp (right) genomic regions are largely CRV specific, containing 48 unique genes which lack similarity to other poxvirus genes. Notably, CRV also contains 14 unique genes which disrupt ChPV gene colinearity within the central genomic region, including 7 genes encoding GyrB-like ATPase domains similar to those in cellular type IIA DNA topoisomerases, suggestive of novel ATP-dependent functions. The presence of 10 CRV proteins with similarity to components of cellular multisubunit E3 ubiquitin-protein ligase complexes, including 9 proteins containing F-box motifs and F-box-associated regions and a homologue of cellular anaphase-promoting complex subunit 11 (Apc11), suggests that modification of host ubiquitination pathways may be significant for CRV-host cell interaction. CRV encodes a novel complement of proteins potentially involved in DNA replication, including a NAD+-dependent DNA ligase and a protein with similarity to both vaccinia virus F16L and prokaryotic serine site-specific resolvase-invertases. CRV lacks genes encoding proteins for nucleotide metabolism. CRV shares notable genomic similarities with molluscum contagiosum virus, including genes found only in these two viruses. Phylogenetic analysis indicates that CRV is quite distinct from other ChPVs, representing a new genus within the subfamily Chordopoxvirinae, and it lacks recognizable homologues of most ChPV genes involved in virulence and host range, including those involving interferon response, intracellular signaling, and host immune response modulation. These data reveal

  20. Genome of crocodilepox virus.

    PubMed

    Afonso, C L; Tulman, E R; Delhon, G; Lu, Z; Viljoen, G J; Wallace, D B; Kutish, G F; Rock, D L

    2006-05-01

    Here, we present the genome sequence, with analysis, of a poxvirus infecting Nile crocodiles (Crocodylus niloticus) (crocodilepox virus; CRV). The genome is 190,054 bp (62% G+C) and predicted to contain 173 genes encoding proteins of 53 to 1,941 amino acids. The central genomic region contains genes conserved and generally colinear with those of other chordopoxviruses (ChPVs). CRV is distinct, as the terminal 33-kbp (left) and 13-kbp (right) genomic regions are largely CRV specific, containing 48 unique genes which lack similarity to other poxvirus genes. Notably, CRV also contains 14 unique genes which disrupt ChPV gene colinearity within the central genomic region, including 7 genes encoding GyrB-like ATPase domains similar to those in cellular type IIA DNA topoisomerases, suggestive of novel ATP-dependent functions. The presence of 10 CRV proteins with similarity to components of cellular multisubunit E3 ubiquitin-protein ligase complexes, including 9 proteins containing F-box motifs and F-box-associated regions and a homologue of cellular anaphase-promoting complex subunit 11 (Apc11), suggests that modification of host ubiquitination pathways may be significant for CRV-host cell interaction. CRV encodes a novel complement of proteins potentially involved in DNA replication, including a NAD(+)-dependent DNA ligase and a protein with similarity to both vaccinia virus F16L and prokaryotic serine site-specific resolvase-invertases. CRV lacks genes encoding proteins for nucleotide metabolism. CRV shares notable genomic similarities with molluscum contagiosum virus, including genes found only in these two viruses. Phylogenetic analysis indicates that CRV is quite distinct from other ChPVs, representing a new genus within the subfamily Chordopoxvirinae, and it lacks recognizable homologues of most ChPV genes involved in virulence and host range, including those involving interferon response, intracellular signaling, and host immune response modulation. These data

  1. Evolution of small prokaryotic genomes

    PubMed Central

    Martínez-Cano, David J.; Reyes-Prieto, Mariana; Martínez-Romero, Esperanza; Partida-Martínez, Laila P.; Latorre, Amparo; Moya, Andrés; Delaye, Luis

    2015-01-01

    As revealed by genome sequencing, the biology of prokaryotes with reduced genomes is strikingly diverse. These include free-living prokaryotes with ∼800 genes as well as endosymbiotic bacteria with as few as ∼140 genes. Comparative genomics is revealing the evolutionary mechanisms that led to these small genomes. In the case of free-living prokaryotes, natural selection directly favored genome reduction, while in the case of endosymbiotic prokaryotes neutral processes played a more prominent role. However, new experimental data suggest that selective processes may be at operation as well for endosymbiotic prokaryotes at least during the first stages of genome reduction. Endosymbiotic prokaryotes have evolved diverse strategies for living with reduced gene sets inside a host-defined medium. These include utilization of host-encoded functions (some of them coded by genes acquired by gene transfer from the endosymbiont and/or other bacteria); metabolic complementation between co-symbionts; and forming consortiums with other bacteria within the host. Recent genome sequencing projects of intracellular mutualistic bacteria showed that previously believed universal evolutionary trends like reduced G+C content and conservation of genome synteny are not always present in highly reduced genomes. Finally, the simplified molecular machinery of some of these organisms with small genomes may be used to aid in the design of artificial minimal cells. Here we review recent genomic discoveries of the biology of prokaryotes endowed with small gene sets and discuss the evolutionary mechanisms that have been proposed to explain their peculiar nature. PMID:25610432

  2. Advances in plant chromosome genomics.

    PubMed

    Doležel, Jaroslav; Vrána, Jan; Cápal, Petr; Kubaláková, Marie; Burešová, Veronika; Simková, Hana

    2014-01-01

    Next generation sequencing (NGS) is revolutionizing genomics and is providing novel insights into genome organization, evolution and function. The number of plant genomes targeted for sequencing is rising. For the moment, however, the acquisition of full genome sequences in large genome species remains difficult, largely because the short reads produced by NGS platforms are inadequate to cope with repeat-rich DNA, which forms a large part of these genomes. The problem of sequence redundancy is compounded in polyploids, which dominate the plant kingdom. An approach to overcoming some of these difficulties is to reduce the full nuclear genome to its individual chromosomes using flow-sorting. The DNA acquired in this way has proven to be suitable for many applications, including PCR-based physical mapping, in situ hybridization, forming DNA arrays, the development of DNA markers, the construction of BAC libraries and positional cloning. Coupling chromosome sorting with NGS offers opportunities for the study of genome organization at the single chromosomal level, for comparative analyses between related species and for the validation of whole genome assemblies. Apart from the primary aim of reducing the complexity of the template, taking a chromosome-based approach enables independent teams to work in parallel, each tasked with the analysis of a different chromosome(s). Given that the number of plant species tractable for chromosome sorting is increasing, the likelihood is that chromosome genomics - the marriage of cytology and genomics - will make a significant contribution to the field of plant genetics. PMID:24406816

  3. Informational laws of genome structures

    PubMed Central

    Bonnici, Vincenzo; Manca, Vincenzo

    2016-01-01

    In recent years, the analysis of genomes by means of strings of length k occurring in the genomes, called k-mers, has provided important insights into the basic mechanisms and design principles of genome structures. In the present study, we focus on the proper choice of the value of k for applying information theoretic concepts that express intrinsic aspects of genomes. The value k = lg2(n), where n is the genome length, is determined to be the best choice in the definition of some genomic informational indexes that are studied and computed for seventy genomes. These indexes, which are based on information entropies and on suitable comparisons with random genomes, suggest five informational laws, to which all of the considered genomes obey. Moreover, an informational genome complexity measure is proposed, which is a generalized logistic map that balances entropic and anti-entropic components of genomes and is related to their evolutionary dynamics. Finally, applications to computational synthetic biology are briefly outlined. PMID:27354155

  4. Informational laws of genome structures.

    PubMed

    Bonnici, Vincenzo; Manca, Vincenzo

    2016-01-01

    In recent years, the analysis of genomes by means of strings of length k occurring in the genomes, called k-mers, has provided important insights into the basic mechanisms and design principles of genome structures. In the present study, we focus on the proper choice of the value of k for applying information theoretic concepts that express intrinsic aspects of genomes. The value k = lg2(n), where n is the genome length, is determined to be the best choice in the definition of some genomic informational indexes that are studied and computed for seventy genomes. These indexes, which are based on information entropies and on suitable comparisons with random genomes, suggest five informational laws, to which all of the considered genomes obey. Moreover, an informational genome complexity measure is proposed, which is a generalized logistic map that balances entropic and anti-entropic components of genomes and is related to their evolutionary dynamics. Finally, applications to computational synthetic biology are briefly outlined. PMID:27354155

  5. Informational laws of genome structures

    NASA Astrophysics Data System (ADS)

    Bonnici, Vincenzo; Manca, Vincenzo

    2016-06-01

    In recent years, the analysis of genomes by means of strings of length k occurring in the genomes, called k-mers, has provided important insights into the basic mechanisms and design principles of genome structures. In the present study, we focus on the proper choice of the value of k for applying information theoretic concepts that express intrinsic aspects of genomes. The value k = lg2(n), where n is the genome length, is determined to be the best choice in the definition of some genomic informational indexes that are studied and computed for seventy genomes. These indexes, which are based on information entropies and on suitable comparisons with random genomes, suggest five informational laws, to which all of the considered genomes obey. Moreover, an informational genome complexity measure is proposed, which is a generalized logistic map that balances entropic and anti-entropic components of genomes and is related to their evolutionary dynamics. Finally, applications to computational synthetic biology are briefly outlined.

  6. Comparative genomics of Brassicaceae crops

    PubMed Central

    Sharma, Ashutosh; Li, Xiaonan; Lim, Yong Pyo

    2014-01-01

    The family Brassicaceae is one of the major groups of the plant kingdom and comprises diverse species of great economic, agronomic and scientific importance, including the model plant Arabidopsis. The sequencing of the Arabidopsis genome has revolutionized our knowledge in the field of plant biology and provides a foundation in genomics and comparative biology. Genomic resources have been utilized in Brassica for diversity analyses, construction of genetic maps and identification of agronomic traits. In Brassicaceae, comparative sequence analysis across the species has been utilized to understand genome structure, evolution and the detection of conserved genomic segments. In this review, we focus on the progress made in genetic resource development, genome sequencing and comparative mapping in Brassica and related species. The utilization of genomic resources and next-generation sequencing approaches in improvement of Brassica crops is also discussed. PMID:24987286

  7. Toward genome-enabled mycology.

    PubMed

    Hibbett, David S; Stajich, Jason E; Spatafora, Joseph W

    2013-01-01

    Genome-enabled mycology is a rapidly expanding field that is characterized by the pervasive use of genome-scale data and associated computational tools in all aspects of fungal biology. Genome-enabled mycology is integrative and often requires teams of researchers with diverse skills in organismal mycology, bioinformatics and molecular biology. This issue of Mycologia presents the first complete fungal genomes in the history of the journal, reflecting the ongoing transformation of mycology into a genome-enabled science. Here, we consider the prospects for genome-enabled mycology and the technical and social challenges that will need to be overcome to grow the database of complete fungal genomes and enable all fungal biologists to make use of the new data. PMID:23928422

  8. Comparative genomics of Brassicaceae crops.

    PubMed

    Sharma, Ashutosh; Li, Xiaonan; Lim, Yong Pyo

    2014-05-01

    The family Brassicaceae is one of the major groups of the plant kingdom and comprises diverse species of great economic, agronomic and scientific importance, including the model plant Arabidopsis. The sequencing of the Arabidopsis genome has revolutionized our knowledge in the field of plant biology and provides a foundation in genomics and comparative biology. Genomic resources have been utilized in Brassica for diversity analyses, construction of genetic maps and identification of agronomic traits. In Brassicaceae, comparative sequence analysis across the species has been utilized to understand genome structure, evolution and the detection of conserved genomic segments. In this review, we focus on the progress made in genetic resource development, genome sequencing and comparative mapping in Brassica and related species. The utilization of genomic resources and next-generation sequencing approaches in improvement of Brassica crops is also discussed. PMID:24987286

  9. eGenomics: Cataloguing Our Complete Genome Collection III

    PubMed Central

    Field, Dawn; Garrity, George; Gray, Tanya; Selengut, Jeremy; Sterk, Peter; Thomson, Nick; Tatusova, Tatiana; Cochrane, Guy; Glöckner, Frank Oliver; Kottmann, Renzo; Lister, Allyson L.; Tateno, Yoshio; Vaughan, Robert

    2007-01-01

    This meeting report summarizes the proceedings of the “eGenomics: Cataloguing our Complete Genome Collection III” workshop held September 11–13, 2006, at the National Institute for Environmental eScience (NIEeS), Cambridge, United Kingdom. This 3rd workshop of the Genomic Standards Consortium was divided into two parts. The first half of the three-day workshop was dedicated to reviewing the genomic diversity of our current and future genome and metagenome collection, and exploring linkages to a series of existing projects through formal presentations. The second half was dedicated to strategic discussions. Outcomes of the workshop include a revised “Minimum Information about a Genome Sequence” (MIGS) specification (v1.1), consensus on a variety of features to be added to the Genome Catalogue (GCat), agreement by several researchers to adopt MIGS for imminent genome publications, and an agreement by the EBI and NCBI to input their genome collections into GCat for the purpose of quantifying the amount of optional data already available (e.g., for geographic location coordinates) and working towards a single, global list of all public genomes and metagenomes.

  10. The Genomic Standards Consortium

    PubMed Central

    Field, Dawn; Amaral-Zettler, Linda; Cochrane, Guy; Cole, James R.; Dawyndt, Peter; Garrity, George M.; Gilbert, Jack; Glöckner, Frank Oliver; Hirschman, Lynette; Karsch-Mizrachi, Ilene; Klenk, Hans-Peter; Knight, Rob; Kottmann, Renzo; Kyrpides, Nikos; Meyer, Folker; San Gil, Inigo; Sansone, Susanna-Assunta; Schriml, Lynn M.; Sterk, Peter; Tatusova, Tatiana; Ussery, David W.; White, Owen; Wooley, John

    2011-01-01

    A vast and rich body of information has grown up as a result of the world's enthusiasm for 'omics technologies. Finding ways to describe and make available this information that maximise its usefulness has become a major effort across the 'omics world. At the heart of this effort is the Genomic Standards Consortium (GSC), an open-membership organization that drives community-based standardization activities, Here we provide a short history of the GSC, provide an overview of its range of current activities, and make a call for the scientific community to join forces to improve the quality and quantity of contextual information about our public collections of genomes, metagenomes, and marker gene sequences. PMID:21713030

  11. The dog genome.

    PubMed

    Galibert, F; André, C

    2006-01-01

    Over the last few centuries, several hundred dog breeds have been artificially selected through intense breeding, resulting in the modern dog population having the widest polymorphism spectrum in terms of body shape, behavior and aptitude among mammals. Unfortunately, this diversification has predisposed most breeds to specific diseases of genetic origin. The highly fragmented nature of the dog population offers a great opportunity to track the genes and alleles responsible for these diseases as well as for the various phenotypic traits. This has led to a thorough analysis of the dog genome. Here, we report the main results obtained during the last ten years, culminating in the recent publication of a complete dog genome sequence. PMID:18753768

  12. Big cat genomics.

    PubMed

    O'Brien, Stephen J; Johnson, Warren E

    2005-01-01

    Advances in population and quantitative genomics, aided by the computational algorithms that employ genetic theory and practice, are now being applied to biological questions that surround free-ranging species not traditionally suitable for genetic enquiry. Here we review how applications of molecular genetic tools have been used to describe the natural history, present status, and future disposition of wild cat species. Insight into phylogenetic hierarchy, demographic contractions, geographic population substructure, behavioral ecology, and infectious diseases have revealed strategies for survival and adaptation of these fascinating predators. Conservation, stabilization, and management of the big cats are important areas that derive benefit from the genome resources expanded and applied to highly successful species, imperiled by an expanding human population. PMID:16124868

  13. Mapping the human genome

    SciTech Connect

    Annas, G.C.; Elias, S.

    1992-01-01

    This article is a review of the book Mapping the Human Genome: Using Law and Ethics as Guides, edited by George C. Annas and Sherman Elias. The book is a collection of essays on the subject of using ethics and laws as guides to justify human gene mapping. It addresses specific issues such problems related to eugenics, patents, insurance as well as broad issues such as the societal definitions of normality.

  14. Genomic landscape of liposarcoma

    PubMed Central

    Kanojia, Deepika; Nagata, Yasunobu; Garg, Manoj; Lee, Dhong Hyun; Sato, Aiko; Yoshida, Kenichi; Sato, Yusuke; Sanada, Masashi; Mayakonda, Anand; Bartenhagen, Christoph; Klein, Hans-Ulrich; Doan, Ngan B.; Said, Jonathan W.; Mohith, S.; Gunasekar, Swetha; Shiraishi, Yuichi; Chiba, Kenichi; Tanaka, Hiroko; Miyano, Satoru; Myklebost, Ola; Yang, Henry; Dugas, Martin; Meza-Zepeda, Leonardo A.; Silberman, Allan W.; Forscher, Charles; Tyner, Jeffrey W.; Ogawa, Seishi; Koeffler, H. Phillip

    2015-01-01

    Liposarcoma (LPS) is the most common type of soft tissue sarcoma accounting for 20% of all adult sarcomas. Due to absence of clinically effective treatment options in inoperable situations and resistance to chemotherapeutics, a critical need exists to identify novel therapeutic targets. We analyzed LPS genomic landscape using SNP arrays, whole exome sequencing and targeted exome sequencing to uncover the genomic information for development of specific anti-cancer targets. SNP array analysis indicated known amplified genes (MDM2, CDK4, HMGA2) and important novel genes (UAP1, MIR557, LAMA4, CPM, IGF2, ERBB3, IGF1R). Carboxypeptidase M (CPM), recurrently amplified gene in well-differentiated/de-differentiated LPS was noted as a putative oncogene involved in the EGFR pathway. Notable deletions were found at chromosome 1p (RUNX3, ARID1A), chromosome 11q (ATM, CHEK1) and chromosome 13q14.2 (MIR15A, MIR16-1). Significantly and recurrently mutated genes (false discovery rate < 0.05) included PLEC (27%), MXRA5 (21%), FAT3 (24%), NF1 (20%), MDC1 (10%), TP53 (7%) and CHEK2 (6%). Further, in vitro and in vivo functional studies provided evidence for the tumor suppressor role for Neurofibromin 1 (NF1) gene in different subtypes of LPS. Pathway analysis of recurrent mutations demonstrated signaling through MAPK, JAK-STAT, Wnt, ErbB, axon guidance, apoptosis, DNA damage repair and cell cycle pathways were involved in liposarcomagenesis. Interestingly, we also found mutational and copy number heterogeneity within a primary LPS tumor signifying the importance of multi-region sequencing for cancer-genome guided therapy. In summary, these findings provide insight into the genomic complexity of LPS and highlight potential druggable pathways for targeted therapeutic approach. PMID:26643872

  15. Bioinformatics and genomic medicine.

    PubMed

    Kim, Ju Han

    2002-01-01

    Bioinformatics is a rapidly emerging field of biomedical research. A flood of large-scale genomic and postgenomic data means that many of the challenges in biomedical research are now challenges in computational science. Clinical informatics has long developed methodologies to improve biomedical research and clinical care by integrating experimental and clinical information systems. The informatics revolution in both bioinformatics and clinical informatics will eventually change the current practice of medicine, including diagnostics, therapeutics, and prognostics. Postgenome informatics, powered by high-throughput technologies and genomic-scale databases, is likely to transform our biomedical understanding forever, in much the same way that biochemistry did a generation ago. This paper describes how these technologies will impact biomedical research and clinical care, emphasizing recent advances in biochip-based functional genomics and proteomics. Basic data preprocessing with normalization and filtering, primary pattern analysis, and machine-learning algorithms are discussed. Use of integrative biochip informatics technologies, including multivariate data projection, gene-metabolic pathway mapping, automated biomolecular annotation, text mining of factual and literature databases, and the integrated management of biomolecular databases, are also discussed. PMID:12544491

  16. Exploring genomes for glycosyltransferases.

    PubMed

    Hansen, Sara Fasmer; Bettler, Emmanuel; Rinnan, Asmund; Engelsen, Søren B; Breton, Christelle

    2010-10-01

    Glycosyltransferases are one of the largest and most diverse enzyme groups in Nature. They catalyse the synthesis of glycosidic linkages by the transfer of a sugar residue from a donor to an acceptor substrate. These enzymes have been classified into families on the basis of amino acid sequence similarity that are kept updated in the Carbohydrate Active enZyme database (CAZy, ). The repertoire of glycosyltransferases in genomes is believed to determine the diversity of cellular glycan structures, and current estimates suggest that for most genomes about 1% of the coding regions are glycosyltransferases. However, plants tend to have far more glycosyltransferase genes than any other organism sequenced to date, and this can be explained by the highly complex polysaccharide network that form the cell wall and also by the numerous glycosylated secondary metabolites. In recent years, various bioinformatics strategies have been used to search bacterial and plant genomes for new glycosyltransferase genes. These are based on the use of remote homology detection methods that act at the 1D, 2D, and 3D level. The combined use of methods such as profile Hidden Markov Model (HMM) and fold recognition appears to be appropriate for this class of enzyme. Chemometric tools are also particularly well suited for obtaining an overview of multivariate data and revealing hidden latent information when dealing with large and highly complex datasets. PMID:20556308

  17. Cancer Genome Landscapes

    PubMed Central

    Vogelstein, Bert; Papadopoulos, Nickolas; Velculescu, Victor E.; Zhou, Shibin; Diaz, Luis A.; Kinzler, Kenneth W.

    2013-01-01

    Over the past decade, comprehensive sequencing efforts have revealed the genomic landscapes of common forms of human cancer. For most cancer types, this landscape consists of a small number of “mountains” (genes altered in a high percentage of tumors) and a much larger number of “hills” (genes altered infrequently). To date, these studies have revealed ~140 genes that, when altered by intragenic mutations, can promote or “drive” tumorigenesis. A typical tumor contains two to eight of these “driver gene” mutations; the remaining mutations are passengers that confer no selective growth advantage. Driver genes can be classified into 12 signaling pathways that regulate three core cellular processes: cell fate, cell survival, and genome maintenance. A better understanding of these pathways is one of the most pressing needs in basic cancer research. Even now, however, our knowledge of cancer genomes is sufficient to guide the development of more effective approaches for reducing cancer morbidity and mortality. PMID:23539594

  18. Mapping the human genome

    SciTech Connect

    Cantor, Charles R.

    1989-06-01

    The following pages aim to lay a foundation for understanding the excitement surrounding the ''human genome project,'' as well as to convey a flavor of the ongoing efforts and plans at the Human Genome Center at the Lawrence Berkeley Laboratory. Our own work, of course, is only part of a broad international effort that will dramatically enhance our understanding of human molecular genetics before the end of this century. In this country, the bulk of the effort will be carried out under the auspices of the Department of Energy and the National Institutes of Health, but significant contributions have already been made both by nonprofit private foundations and by private corporation. The respective roles of the DOE and the NIH are being coordinated by an inter-agency committee, the aims of which are to emphasize the strengths of each agency, to facilitate cooperation, and to avoid unnecessary duplication of effort. The NIH, for example, will continue its crucial work in medical genetics and in mapping the genomes of nonhuman species. The DOE, on the other hand, has unique experience in managing large projects, and its national laboratories are repositories of expertise in physics, engineering, and computer science, as well as the life sciences. The tools and techniques the project will ultimately rely on are thus likely to be developed in multidisciplinary efforts at laboratories like LBL. Accordingly, we at LBL take great pride in this enterprise -- an enterprise that will eventually transform our understanding of ourselves.

  19. Translational genomics for plant breeding with the genome sequence explosion.

    PubMed

    Kang, Yang Jae; Lee, Taeyoung; Lee, Jayern; Shim, Sangrea; Jeong, Haneul; Satyawan, Dani; Kim, Moon Young; Lee, Suk-Ha

    2016-04-01

    The use of next-generation sequencers and advanced genotyping technologies has propelled the field of plant genomics in model crops and plants and enhanced the discovery of hidden bridges between genotypes and phenotypes. The newly generated reference sequences of unstudied minor plants can be annotated by the knowledge of model plants via translational genomics approaches. Here, we reviewed the strategies of translational genomics and suggested perspectives on the current databases of genomic resources and the database structures of translated information on the new genome. As a draft picture of phenotypic annotation, translational genomics on newly sequenced plants will provide valuable assistance for breeders and researchers who are interested in genetic studies. PMID:26269219

  20. The fungal genome initiative and lessons learned from genome sequencing.

    PubMed

    Cuomo, Christina A; Birren, Bruce W

    2010-01-01

    The sequence of Saccharomyces cerevisiae enabled systematic genome-wide experimental approaches, demonstrating the power of having the complete genome of an organism. The rapid impact of these methods on research in yeast mobilized an effort to expand genomic resources for other fungi. The "fungal genome initiative" represents an organized genome sequencing effort to promote comparative and evolutionary studies across the fungal kingdom. Through such an approach, scientists can not only better understand specific organisms but also illuminate the shared and unique aspects of fungal biology that underlie the importance of fungi in biomedical research, health, food production, and industry. To date, assembled genomes for over 100 fungi are available in public databases, and many more sequencing projects are underway. Here, we discuss both examples of findings from comparative analysis of fungal sequences, with a specific emphasis on yeast genomes, and on the analytical approaches taken to mine fungal genomes. New sequencing methods are accelerating comparative studies of fungi by reducing the cost and difficulty of sequencing. This has driven more common use of sequencing applications, such as to study genome-wide variation in populations or to deeply profile RNA transcripts. These and further technological innovations will continue to be piloted in yeasts and other fungi, and will expand the applications of sequencing to study fungal biology. PMID:20946837

  1. Genomic Data Commons and Genomic Cloud Pilots - Google Hangout

    Cancer.gov

    Join us for a live, moderated discussion about two NCI efforts to expand access to cancer genomics data: the Genomic Data Commons and Genomic Cloud Pilots. NCI subject matters experts will include Louis M. Staudt, M.D., Ph.D., Director Center for Cancer Genomics, Warren Kibbe, Ph.D., Director, NCI Center for Biomedical Informatics and Information Technology, and moderated by Anthony Kerlavage, Ph.D., Chief, Cancer Informatics Branch, Center for Biomedical Informatics and Information Technology. We welcome your questions before and during the Hangout on Twitter using the hashtag #AskNCI.

  2. The coffee genome hub: a resource for coffee genomes

    PubMed Central

    Dereeper, Alexis; Bocs, Stéphanie; Rouard, Mathieu; Guignon, Valentin; Ravel, Sébastien; Tranchant-Dubreuil, Christine; Poncet, Valérie; Garsmeur, Olivier; Lashermes, Philippe; Droc, Gaëtan

    2015-01-01

    The whole genome sequence of Coffea canephora, the perennial diploid species known as Robusta, has been recently released. In the context of the C. canephora genome sequencing project and to support post-genomics efforts, we developed the Coffee Genome Hub (http://coffee-genome.org/), an integrative genome information system that allows centralized access to genomics and genetics data and analysis tools to facilitate translational and applied research in coffee. We provide the complete genome sequence of C. canephora along with gene structure, gene product information, metabolism, gene families, transcriptomics, syntenic blocks, genetic markers and genetic maps. The hub relies on generic software (e.g. GMOD tools) for easy querying, visualizing and downloading research data. It includes a Genome Browser enhanced by a Community Annotation System, enabling the improvement of automatic gene annotation through an annotation editor. In addition, the hub aims at developing interoperability among other existing South Green tools managing coffee data (phylogenomics resources, SNPs) and/or supporting data analyses with the Galaxy workflow manager. PMID:25392413

  3. The Saccharomyces Genome Database: Exploring Genome Features and Their Annotations.

    PubMed

    Cherry, J Michael

    2015-12-01

    Genomic-scale assays result in data that provide information over the entire genome. Such base pair resolution data cannot be summarized easily except via a graphical viewer. A genome browser is a tool that displays genomic data and experimental results as horizontal tracks. Genome browsers allow searches for a chromosomal coordinate or a feature, such as a gene name, but they do not allow searches by function or upstream binding site. Entry into a genome browser requires that you identify the gene name or chromosomal coordinates for a region of interest. A track provides a representation for genomic results and is displayed as a row of data shown as line segments to indicate regions of the chromosome with a feature. Another type of track presents a graph or wiggle plot that indicates the processed signal intensity computed for a particular experiment or set of experiments. Wiggle plots are typical for genomic assays such as the various next-generation sequencing methods (e.g., chromatin immunoprecipitation [ChIP]-seq or RNA-seq), where it represents a peak of DNA binding, histone modification, or the mapping of an RNA sequence. Here we explore the browser that has been built into the Saccharomyces Genome Database (SGD). PMID:26631126

  4. Flexible genomic islands as drivers of genome evolution.

    PubMed

    Rodriguez-Valera, Francisco; Martin-Cuadrado, Ana-Belen; López-Pérez, Mario

    2016-06-01

    Natural prokaryotic populations are composed of multiple clonal lineages that are different in their core genomes in a range that varies typically between 95 and 100% nucleotide identity. Each clonal lineage also carries a complement of not shared flexible genes that can be very large. The compounded flexible genome provides polyclonal populations with enormous gene diversity that can be used to efficiently exploit resources. This has fundamental repercussions for interpreting individual bacterial genomes. They are better understood as parts rather than the whole. Multiple genomes are required to understand how the population interacts with its biotic and abiotic environment. PMID:27085300

  5. Defining Genome Maintenance Pathways using Functional Genomic Approaches

    PubMed Central

    Bansbach, Carol E.; Cortez, David

    2011-01-01

    Genome maintenance activities including DNA repair, cell division cycle control, and checkpoint signaling pathways preserve genome integrity and prevent disease. Defects in these pathways cause birth defects, neurodegeneration, premature aging, and cancer. Recent technical advances in functional genomic approaches such as expression profiling, proteomics, and RNA interference (RNAi) technologies have rapidly expanded our knowledge of the proteins that work in these pathways. In this review, we examine the use of these high-throughput methodologies in higher eukaryotic organisms for the interrogation of genome maintenance activities. PMID:21787120

  6. Genome Projector: zoomable genome map with multiple views

    PubMed Central

    Arakawa, Kazuharu; Tamaki, Satoshi; Kono, Nobuaki; Kido, Nobuhiro; Ikegami, Keita; Ogawa, Ryu; Tomita, Masaru

    2009-01-01

    Background Molecular biology data exist on diverse scales, from the level of molecules to -omics. At the same time, the data at each scale can be categorised into multiple layers, such as the genome, transcriptome, proteome, metabolome, and biochemical pathways. Due to the highly multi-layer and multi-dimensional nature of biological information, software interfaces for database browsing should provide an intuitive interface that allows for rapid migration across different views and scales. The Zoomable User Interface (ZUI) and tabbed browsing have proven successful for this purpose in other areas, especially to navigate the vast information in the World Wide Web. Results This paper presents Genome Projector, a Web-based gateway for genomics information with a zoomable user interface using Google Maps API, equipped with four seamlessly accessible and searchable views: a circular genome map, a traditional genome map, a biochemical pathways map, and a DNA walk map. The Web application for 320 bacterial genomes is available at . All data and software including the source code, documentations, and development API are freely available under the GNU General Public License. Zoomable maps can be easily created from any image file using the development API, and an online data mapping service for Genome Projector is also available at our Web site. Conclusion Genome Projector is an intuitive Web application for browsing genomics information, implemented with a zoomable user interface and tabbed browsing utilising Google Maps API and Asynchronous JavaScript and XML (AJAX) technology. PMID:19166610

  7. The Anolis Lizard Genome: An Amniote Genome without Isochores?

    PubMed Central

    Costantini, Maria; Greif, Gonzalo; Alvarez-Valin, Fernando; Bernardi, Giorgio

    2016-01-01

    Two articles published 5 years ago concluded that the genome of the lizard Anolis carolinensis is an amniote genome without isochores. This claim was apparently contradicting previous results on the general presence of an isochore organization in all vertebrate genomes tested (including Anolis). In this investigation, we demonstrate that the Anolis genome is indeed heterogeneous in base composition, since its macrochromosomes comprise isochores mainly from the L2 and H1 families (a moderately GC-poor and a moderately GC-rich family, respectively), and since the majority of the sequenced microchromosomes consists of H1 isochores. These families are associated with different features of genome structure, including gene density and compositional correlations (e.g., GC3 vs flanking sequence GC and intron GC), as in the case of mammalian and avian genomes. Moreover, the assembled Anolis chromosomes have an enormous number of gaps, which could be due to sequencing problems in GC-rich regions of the genome. In conclusion, the Anolis genome is no exception to the general rule of an isochore organization in the genomes of vertebrates (and other eukaryotes). PMID:26992416

  8. The coffee genome hub: a resource for coffee genomes.

    PubMed

    Dereeper, Alexis; Bocs, Stéphanie; Rouard, Mathieu; Guignon, Valentin; Ravel, Sébastien; Tranchant-Dubreuil, Christine; Poncet, Valérie; Garsmeur, Olivier; Lashermes, Philippe; Droc, Gaëtan

    2015-01-01

    The whole genome sequence of Coffea canephora, the perennial diploid species known as Robusta, has been recently released. In the context of the C. canephora genome sequencing project and to support post-genomics efforts, we developed the Coffee Genome Hub (http://coffee-genome.org/), an integrative genome information system that allows centralized access to genomics and genetics data and analysis tools to facilitate translational and applied research in coffee. We provide the complete genome sequence of C. canephora along with gene structure, gene product information, metabolism, gene families, transcriptomics, syntenic blocks, genetic markers and genetic maps. The hub relies on generic software (e.g. GMOD tools) for easy querying, visualizing and downloading research data. It includes a Genome Browser enhanced by a Community Annotation System, enabling the improvement of automatic gene annotation through an annotation editor. In addition, the hub aims at developing interoperability among other existing South Green tools managing coffee data (phylogenomics resources, SNPs) and/or supporting data analyses with the Galaxy workflow manager. PMID:25392413

  9. Mosquito genomics: progress and challenges.

    PubMed

    Severson, David W; Behura, Susanta K

    2012-01-01

    The whole-genome sequencing of mosquitoes has facilitated our understanding of fundamental biological processes at their basic molecular levels and holds potential for application to mosquito control and prevention of mosquito-borne disease transmission. Draft genome sequences are available for Anopheles gambiae, Aedes aegypti, and Culex quinquefasciatus. Collectively, these represent the major vectors of African malaria, dengue fever and yellow fever viruses, and lymphatic filariasis, respectively. Rapid advances in genome technologies have revealed detailed information on genome architecture as well as phenotype-specific transcriptomics and proteomics. These resources allow for detailed comparative analyses within and across populations as well as species. Next-generation sequencing technologies will likely promote a proliferation of genome sequences for additional mosquito species as well as for individual insects. Here we review the current status of genome research in mosquitoes and identify potential areas for further investigations. PMID:21942845

  10. Invariants of DNA genomic signals

    NASA Astrophysics Data System (ADS)

    Cristea, Paul Dan A.

    2005-02-01

    For large scale analysis purposes, the conversion of genomic sequences into digital signals opens the possibility to use powerful signal processing methods for handling genomic information. The study of complex genomic signals reveals large scale features, maintained over the scale of whole chromosomes, that would be difficult to find by using only the symbolic representation. Based on genomic signal methods and on statistical techniques, the paper defines parameters of DNA sequences which are invariant to transformations induced by SNPs, splicing or crossover. Re-orienting concatenated coding regions in the same direction, regularities shared by the genomic material in all exons are revealed, pointing towards the hypothesis of a regular ancestral structure from which the current chromosome structures have evolved. This property is not found in non-nuclear genomic material, e.g., plasmids.

  11. The genome of Eucalyptus grandis.

    PubMed

    Myburg, Alexander A; Grattapaglia, Dario; Tuskan, Gerald A; Hellsten, Uffe; Hayes, Richard D; Grimwood, Jane; Jenkins, Jerry; Lindquist, Erika; Tice, Hope; Bauer, Diane; Goodstein, David M; Dubchak, Inna; Poliakov, Alexandre; Mizrachi, Eshchar; Kullan, Anand R K; Hussey, Steven G; Pinard, Desre; van der Merwe, Karen; Singh, Pooja; van Jaarsveld, Ida; Silva-Junior, Orzenil B; Togawa, Roberto C; Pappas, Marilia R; Faria, Danielle A; Sansaloni, Carolina P; Petroli, Cesar D; Yang, Xiaohan; Ranjan, Priya; Tschaplinski, Timothy J; Ye, Chu-Yu; Li, Ting; Sterck, Lieven; Vanneste, Kevin; Murat, Florent; Soler, Marçal; Clemente, Hélène San; Saidi, Naijib; Cassan-Wang, Hua; Dunand, Christophe; Hefer, Charles A; Bornberg-Bauer, Erich; Kersting, Anna R; Vining, Kelly; Amarasinghe, Vindhya; Ranik, Martin; Naithani, Sushma; Elser, Justin; Boyd, Alexander E; Liston, Aaron; Spatafora, Joseph W; Dharmwardhana, Palitha; Raja, Rajani; Sullivan, Christopher; Romanel, Elisson; Alves-Ferreira, Marcio; Külheim, Carsten; Foley, William; Carocha, Victor; Paiva, Jorge; Kudrna, David; Brommonschenkel, Sergio H; Pasquali, Giancarlo; Byrne, Margaret; Rigault, Philippe; Tibbits, Josquin; Spokevicius, Antanas; Jones, Rebecca C; Steane, Dorothy A; Vaillancourt, René E; Potts, Brad M; Joubert, Fourie; Barry, Kerrie; Pappas, Georgios J; Strauss, Steven H; Jaiswal, Pankaj; Grima-Pettenati, Jacqueline; Salse, Jérôme; Van de Peer, Yves; Rokhsar, Daniel S; Schmutz, Jeremy

    2014-06-19

    Eucalypts are the world's most widely planted hardwood trees. Their outstanding diversity, adaptability and growth have made them a global renewable resource of fibre and energy. We sequenced and assembled >94% of the 640-megabase genome of Eucalyptus grandis. Of 36,376 predicted protein-coding genes, 34% occur in tandem duplications, the largest proportion thus far in plant genomes. Eucalyptus also shows the highest diversity of genes for specialized metabolites such as terpenes that act as chemical defence and provide unique pharmaceutical oils. Genome sequencing of the E. grandis sister species E. globulus and a set of inbred E. grandis tree genomes reveals dynamic genome evolution and hotspots of inbreeding depression. The E. grandis genome is the first reference for the eudicot order Myrtales and is placed here sister to the eurosids. This resource expands our understanding of the unique biology of large woody perennials and provides a powerful tool to accelerate comparative biology, breeding and biotechnology. PMID:24919147

  12. Big Data: Astronomical or Genomical?

    PubMed

    Stephens, Zachary D; Lee, Skylar Y; Faghri, Faraz; Campbell, Roy H; Zhai, Chengxiang; Efron, Miles J; Iyer, Ravishankar; Schatz, Michael C; Sinha, Saurabh; Robinson, Gene E

    2015-07-01

    Genomics is a Big Data science and is going to get much bigger, very soon, but it is not known whether the needs of genomics will exceed other Big Data domains. Projecting to the year 2025, we compared genomics with three other major generators of Big Data: astronomy, YouTube, and Twitter. Our estimates show that genomics is a "four-headed beast"--it is either on par with or the most demanding of the domains analyzed here in terms of data acquisition, storage, distribution, and analysis. We discuss aspects of new technologies that will need to be developed to rise up and meet the computational challenges that genomics poses for the near future. Now is the time for concerted, community-wide planning for the "genomical" challenges of the next decade. PMID:26151137

  13. Genomics Nursing Faculty Champion Initiative

    PubMed Central

    Jenkins, Jean; Calzone, Kathleen A.

    2016-01-01

    Nurse faculty are challenged to keep up with the emerging and fast-paced field of genomics and the mandate to prepare the nursing workforce to be able to translate genomic research advances into routine clinical care. Using Faculty Champions and other options, the initiative stimulated curriculum development and promoted genomics curriculum integration. The authors summarize this yearlong initiative for undergraduate and graduate nursing faculty. PMID:24300251

  14. Cactus Graphs for Genome Comparisons

    NASA Astrophysics Data System (ADS)

    Paten, Benedict; Diekhans, Mark; Earl, Dent; St. John, John; Ma, Jian; Suh, Bernard; Haussler, David

    We introduce a data structure, analysis and visualization scheme called a cactus graph for comparing sets of related genomes. Cactus graphs capture some of the advantages of de Bruijn and breakpoint graphs in one unified framework. They naturally decompose the common substructures in a set of related genomes into a hierarchy of chains that can be visualized as multiple alignments and nets that can be visualized in circular genome plots.

  15. Programs | Office of Cancer Genomics

    Cancer.gov

    OCG facilitates cancer genomics research through a series of highly-focused programs. These programs generate and disseminate genomic data for use by the cancer research community. OCG programs also promote advances in technology-based infrastructure and create valuable experimental reagents and tools. OCG programs encourage collaboration by interconnecting with other genomics and cancer projects in order to accelerate translation of findings into the clinic. Below are OCG’s current, completed, and initiated programs:

  16. Synthetic hexaploid wheat and its utilization for wheat genetic improvement in China.

    PubMed

    Yang, Wuyun; Liu, Dengcai; Li, Jun; Zhang, Lianquan; Wei, Huiting; Hu, Xiaorong; Zheng, Youliang; He, Zhouhu; Zou, Yuchun

    2009-09-01

    Synthetic hexaploid wheat (Triticum turgidumxAegilops tauschii) was created to explore for novel genes from T. turgidum and Ae. tauschii that can be used for common wheat improvement. In the present paper, research advances on the utilization of synthetic hexaploid wheat for wheat genetic improvement in China are reviewed. Over 200 synthetic hexaploid wheat (SHW) accessions from the International Maize and Wheat Improvement Centre (CIMMYT) were introduced into China since 1995. Four cultivars derived from these, Chuanmai 38, Chuanmai 42, Chuanmai 43 and Chuanmai 47, have been released in China. Of these, Chuanmai 42, with large kernels and resistance to stripe rust, had the highest average yield (>6 t/ha) among all cultivars over two years in Sichuan provincial yield trials, outyielding the commercial check cultivar Chuanmai 107 by 22.7%. Meanwhile, by either artificial chromosome doubling via colchicine treatment or spontaneous chromosome doubling via a union of unreduced gametes (2n) from T. turgidum-Ae. tauschii hybrids, new SHW lines were produced in China. Mitotic-like meiosis might be the cytological mechanism of spontaneous chromosome doubling. SHW lines with genes for spontaneous chromosome doubling may be useful for producing new SHW-alien amphidiploids and double haploid in wheat genetic improvement. PMID:19782955

  17. Genome walking by Klenow polymerase.

    PubMed

    Volpicella, Mariateresa; Leoni, Claudia; Fanizza, Immacolata; Rius, Sebastian; Gallerani, Raffaele; Ceci, Luigi R

    2012-11-15

    Genome walking procedures are all based on a final polymerase chain reaction amplification, regardless of the strategy employed for the synthesis of the substrate molecule. Here we report a modification of an already established genome walking strategy in which a single-strand DNA substrate is obtained by primer extension driven by Klenow polymerase and which results suitable for the direct sequencing of complex eukaryotic genomes. The efficacy of the method is demonstrated by the identification of nucleotide sequences in the case of two gene families (chiA and P1) in the genomes of several maize species. PMID:22922302

  18. Global efforts in structural genomics.

    PubMed

    Stevens, R C; Yokoyama, S; Wilson, I A

    2001-10-01

    A worldwide initiative in structural genomics aims to capitalize on the recent successes of the genome projects. Substantial new investments in structural genomics in the past 2 years indicate the high level of support for these international efforts. Already, enormous progress has been made on high-throughput methodologies and technologies that will speed up macromolecular structure determinations. Recent international meetings have resulted in the formation of an International Structural Genomics Organization to formulate policy and foster cooperation between the public and private efforts. PMID:11588249

  19. Genomic medicine and neurological disease

    PubMed Central

    Boone, Philip M.; Wiszniewski, Wojciech; Lupski, James R.

    2011-01-01

    Genomic medicine” refers to the diagnosis, optimized management, and treatment of disease—as well as screening, counseling, and disease gene identification—in the context of information provided by an individual patient’s personal genome. Genomic medicine, to some extent synonymous with “personalized medicine,” has been made possible by recent advances in genome technologies. Genomic medicine represents a new approach to health care and disease management that attempts to optimize the care of a patient based upon information gleaned from his or her personal genome sequence. In this review, we describe recent progress in genomic medicine as it relates to neurological disease. Many neurological disorders either segregate as Mendelian phenotypes or occur sporadically in association with a new mutation in a single gene. Heritability also contributes to other neurological conditions that appear to exhibit more complex genetics. In addition to discussing current knowledge in this field, we offer suggestions for maximizing the utility of genomic information in clinical practice as the field of genomic medicine unfolds. PMID:21594611

  20. Genomics of Bacillus Species

    NASA Astrophysics Data System (ADS)

    Økstad, Ole Andreas; Kolstø, Anne-Brit

    Members of the genus Bacillus are rod-shaped spore-forming bacteria belonging to the Firmicutes, the low G+C gram-positive bacteria. The Bacillus genus was first described and classified by Ferdinand Cohn in Cohn (1872), and Bacillus subtilis was defined as the type species (Soule, 1932). Several Bacilli may be linked to opportunistic infections. However, pathogenicity among Bacillus spp. is mainly a feature of bacteria belonging to the Bacillus cereus group, including B. cereus, Bacillus anthracis, and Bacillus thuringiensis. Here we review the genomics of B. cereus group bacteria in relation to their roles as etiological agents of two food poisoning syndromes (emetic and diarrhoeal).

  1. The human genome project

    SciTech Connect

    Bell, G.I.

    1991-06-01

    The Human Genome Project will obtain high-resolution genetic and physical maps of each human chromosome and, somewhat later, of the complete nucleotide sequence of the deoxyribonucleic acid (DNA) in a human cell. The talk will begin with an extended introduction to explain the Project to nonbiologists and to show that map construction and sequence determination require extensive computation in order to determine the correct order of the mapped entities and to provide estimates of uncertainty. Computational analysis of the sequence data will become an increasingly important part of the project, and some computational challenges are described. 5 refs.

  2. Human Genome Program Image Gallery (from genomics.energy.gov)

    DOE Data Explorer

    This collection contains approximately 240 images from the genome programs of DOE's Office of Science. The images are divided into galleries related to biofuels research, systems biology, and basic genomics. Each image has a title, a basic citation, and a credit or source. Most of the images are original graphics created by the Genome Management Information System (GMIS). GMIS images are recognizable by their credit line. Permission to use these graphics is not needed, but please credit the U.S. Department of Energy Genome Programs and provide the website http://genomics.energy.gov. Other images were provided by third parties and not created by the U.S. Department of Energy. Users must contact the person listed in the credit line before using those images. The high-resolution images can be downloaded.

  3. A Taste of Algal Genomes from the Joint Genome Institute

    SciTech Connect

    Kuo, Alan; Grigoriev, Igor

    2012-06-17

    Algae play profound roles in aquatic food chains and the carbon cycle, can impose health and economic costs through toxic blooms, provide models for the study of symbiosis, photosynthesis, and eukaryotic evolution, and are candidate sources for bio-fuels; all of these research areas are part of the mission of DOE's Joint Genome Institute (JGI). To date JGI has sequenced, assembled, annotated, and released to the public the genomes of 18 species and strains of algae, sampling almost all of the major clades of photosynthetic eukaryotes. With more algal genomes currently undergoing analysis, JGI continues its commitment to driving forward basic and applied algal science. Among these ongoing projects are the pan-genome of the dominant coccolithophore Emiliania huxleyi, the interrelationships between the 4 genomes in the nucleomorph-containing Bigelowiella natans and Guillardia theta, and the search for symbiosis genes of lichens.

  4. Modifying the Mitochondrial Genome.

    PubMed

    Patananan, Alexander N; Wu, Ting-Hsiang; Chiou, Pei-Yu; Teitell, Michael A

    2016-05-10

    Human mitochondria produce ATP and metabolites to support development and maintain cellular homeostasis. Mitochondria harbor multiple copies of a maternally inherited, non-nuclear genome (mtDNA) that encodes for 13 subunit proteins of the respiratory chain. Mutations in mtDNA occur mainly in the 24 non-coding genes, with specific mutations implicated in early death, neuromuscular and neurodegenerative diseases, cancer, and diabetes. A significant barrier to new insights in mitochondrial biology and clinical applications for mtDNA disorders is our general inability to manipulate the mtDNA sequence. Microinjection, cytoplasmic fusion, nucleic acid import strategies, targeted endonucleases, and newer approaches, which include the transfer of genomic DNA, somatic cell reprogramming, and a photothermal nanoblade, attempt to change the mtDNA sequence in target cells with varying efficiencies and limitations. Here, we discuss the current state of manipulating mammalian mtDNA and provide an outlook for mitochondrial reverse genetics, which could further enable mitochondrial research and therapies for mtDNA diseases. PMID:27166943

  5. Parsing of genomic graffiti

    SciTech Connect

    Tibbetts, C.; Golden, J. III; Torgersen, D.

    1996-12-31

    A focal point of modern biology is investigation of wide varieties of phenomena at the level of molecular genetics. The nucleotide sequences of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) define the ultimate resolution of this reductionist approach to understand the determinants of heritable traits. The structure and function of genes, their composite genomic organization, and their regulated expression have been studied in systems representing every class of organism. Many human diseases or pathogenic syndromes can be directly attributed to inherited defects in either the regulated expression, or the quality of the products of specific genes. Genetic determinants of susceptibility to infectious agents or environmental hazards are amply documented. Mapping and sequencing of the DNA molecules encoding human genes have provided powerful technology for pharmaceutical bioengineering and forensic investigations. From an alternative perspective, we may anticipate that voluminous archives of singular DNA sequences alone will not suffice to define and understand the functional determinants of genome organization, allelic diversity and evolutionary plasticity of living organisms. New insights will accumulate pertaining to human evolutionary origins and relationships of human biology to models based on other mammals. Investigators of population genetics and epidemiology now exploit the technology of molecular genetics to more powerfully probe variation within the human gene pool at the level of DNA sequences. 40 refs., 7 figs., 2 tabs.

  6. Genomic imprinting and cancer.

    PubMed

    Brenton, J D; Viville, S; Surani, M A

    1995-01-01

    Imprinting is vital for normal development, and disruption of imprinting mechanisms on syntenic chromosomes gives very similar phenotypes in mouse and humans. In addition, disruption of normal imprinting provides a plausible explanation for preferential LOH in some embryonal tumours. Moreover, there is evidence that in Wilms' tumour, dysregulation of specific imprinted genes may give rise to the cancer phenotype. Many more questions regarding genomic imprinting need to be answered before the associations described in this review can be properly understood. The most basic issues, such as when and how the imprint is established, can still only be speculated upon. Further study of new imprinted genes and the relationship between their domains and differential replication may show us higher control mechanisms than methylation alone. It remains to be seen if these epigenetic modifications are amenable to therapeutic change in the treatment of inherited syndromes and cancer, or if they can be used to assess individuals at risk of disease. Until then it is probably unwise to speculate on a single unifying theory that explains why a subset of the genome shows such a peculiar non-Mendelian form of inheritance. PMID:8718517

  7. OryzaGenome: Genome Diversity Database of Wild Oryza Species

    PubMed Central

    Ohyanagi, Hajime; Ebata, Toshinobu; Huang, Xuehui; Gong, Hao; Fujita, Masahiro; Mochizuki, Takako; Toyoda, Atsushi; Fujiyama, Asao; Kaminuma, Eli; Nakamura, Yasukazu; Feng, Qi; Wang, Zi-Xuan; Han, Bin; Kurata, Nori

    2016-01-01

    The species in the genus Oryza, encompassing nine genome types and 23 species, are a rich genetic resource and may have applications in deeper genomic analyses aiming to understand the evolution of plant genomes. With the advancement of next-generation sequencing (NGS) technology, a flood of Oryza species reference genomes and genomic variation information has become available in recent years. This genomic information, combined with the comprehensive phenotypic information that we are accumulating in our Oryzabase, can serve as an excellent genotype–phenotype association resource for analyzing rice functional and structural evolution, and the associated diversity of the Oryza genus. Here we integrate our previous and future phenotypic/habitat information and newly determined genotype information into a united repository, named OryzaGenome, providing the variant information with hyperlinks to Oryzabase. The current version of OryzaGenome includes genotype information of 446 O. rufipogon accessions derived by imputation and of 17 accessions derived by imputation-free deep sequencing. Two variant viewers are implemented: SNP Viewer as a conventional genome browser interface and Variant Table as a text-based browser for precise inspection of each variant one by one. Portable VCF (variant call format) file or tab-delimited file download is also available. Following these SNP (single nucleotide polymorphism) data, reference pseudomolecules/scaffolds/contigs and genome-wide variation information for almost all of the closely and distantly related wild Oryza species from the NIG Wild Rice Collection will be available in future releases. All of the resources can be accessed through http://viewer.shigen.info/oryzagenome/. PMID:26578696

  8. Co-existence of salt and drought tolerance in Triticeae.

    PubMed

    Farooq, S; Azam, F

    2001-01-01

    Cell membrane stability (CMS) technique was used to screen for drought tolerance, salt tolerant accessions of three Aegilops species, Ae. tauschii, Ae. cylindrica, Ae. geniculata and two hexaploid wheat (Tricitum aestivum L.) cultivars comprising salt tolerant LU-26 and drought tolerant Chakwal-86. The objectives were to see how valid it is for a salt tolerant plant to be drought tolerant as well and to identify the character(s) that may contribute to drought tolerance. Three moisture levels equal to 100, 50 and 25% saturation capacity of the soil were used for plant cultivation. Injury percentage (IP) based on in-vitro desiccation induced by polyethylene glycol (PEG) in leaf tissue was measured through the conductivity of the electrolyte leakage. Injury percentage decreased in all the test material with decrease in soil moisture contents. Ae. cylindrica exhibited minimum injury at 100% soil moisture level followed by Ae. tauschii and Ae. geniculata while drought tolerant wheat cultivars exhibited the maximum. The wheat cultivar Chakwal-86 has been developed for dry areas, with low soil moisture levels, and high water potential enhances the injury percentage. Aegilops cylindrica is a salt tolerant species and can thus tolerate water deficit conditions created due to low osmotic potential. Potassium appeared to play an important role in drought tolerance which was evident from high K+ contents and low K+ leakage from Aegilops cylindrica and drought tolerant wheat cultivar Chakwal-86. It was inferred from the study that salt tolerant species might prove drought tolerant in the areas where water deficit prevails due to the ability to create low intracellular osmotic potentials. PMID:12152336

  9. All about the Human Genome Project (HGP)

    MedlinePlus

    ... full human sequence All About The Human Genome Project (HGP) The Human Genome Project (HGP) was one of the great feats of ... Organisms A Quarter Century after the Human Genome Project's Launch: Lessons Beyond the Base Pairs October 1, ...

  10. International genomic evaluation methods for dairy cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background Genomic evaluations are rapidly replacing traditional evaluation systems used for dairy cattle selection. Economies of scale in genomics promote cooperation across country borders. Genomic information can be transferred across countries using simple conversion equations, by modifying mult...

  11. Surveying Breast Cancer's Genomic Landscape.

    PubMed

    2016-07-01

    An in-depth analysis has produced the most comprehensive portrait to date of the myriad genomic alterations involved in breast cancer. In sequencing the whole genomes of 560 breast cancers and combining this information with published data from another 772 breast tumors, the research team uncovered several new genes and mutational signatures that potentially influence this disease. PMID:27225883

  12. CROP GENOME DATABASES -- CRITICAL ISSUES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Crop genome databases, see www.agron.missouri.edu/bioservers.html of the past decade have had designed and implemented (1) models and schema for the genome and related domains; (2) methodologies for input of data by expert biologists and high-throughput projects; and (3) various text, graphical, and...

  13. Cocoa/Cotton Comparative Genomics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    With genome sequence from two members of the Malvaceae family recently made available, we are exploring syntenic relationships, gene content, and evolutionary trajectories between the cacao and cotton genomes. An assembly of cacao (Theobroma cacao) using Illumina and 454 sequence technology yielded ...

  14. Genomics and Weeds: A Synthesis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genomics can be used to solve many problems associated with the management of weeds. New target sites for herbicides have been discovered through functional genomic approaches to determine gene function. Modes of action of herbicides can be clarified or discovered by transcriptome analysis. Under...

  15. Plant cytogenetics in genome databases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cytogenetic maps provide an integrated representation of genetic and cytological information that can be used to enhance genome and chromosome research. As genome analysis technologies become more affordable, the density of markers on cytogenetic maps increases, making these resources more useful a...

  16. From genes to genome biology

    SciTech Connect

    Pennisi, E.

    1996-06-21

    This article describes a change in the approach to mapping genomes, from looking at one gene at a time, to other approaches. Strategies include everything from lab techniques to computer programs designed to analyze whole batches of genes at once. Also included is a update on the work on the human genome.

  17. Fueling Future with Algal Genomics

    SciTech Connect

    Grigoriev, Igor

    2012-07-05

    Algae constitute a major component of fundamental eukaryotic diversity, play profound roles in the carbon cycle, and are prominent candidates for biofuel production. The US Department of Energy Joint Genome Institute (JGI) is leading the world in algal genome sequencing (http://jgi.doe.gov/Algae) and contributes of the algal genome projects worldwide (GOLD database, 2012). The sequenced algal genomes offer catalogs of genes, networks, and pathways. The sequenced first of its kind genomes of a haptophyte E.huxleyii, chlorarachniophyte B.natans, and cryptophyte G.theta fill the gaps in the eukaryotic tree of life and carry unique genes and pathways as well as molecular fossils of secondary endosymbiosis. Natural adaptation to conditions critical for industrial production is encoded in algal genomes, for example, growth of A.anophagefferens at very high cell densities during the harmful algae blooms or a global distribution across diverse environments of E.huxleyii, able to live on sparse nutrients due to its expanded pan-genome. Communications and signaling pathways can be derived from simple symbiotic systems like lichens or complex marine algae metagenomes. Collectively these datasets derived from algal genomics contribute to building a comprehensive parts list essential for algal biofuel development.

  18. Genomic Evaluations: Past, Present, Future

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genomic evaluation has been implemented in dairy cattle causing profound changes in dairy cattle breeding. All young bulls purchased by major AI organizations are selected based on genomic evaluations. The reliability of these evaluations reaches the mid seventies for yield traits and is adequate to...

  19. Functional Genomics Tools for Papaya

    Technology Transfer Automated Retrieval System (TEKTRAN)

    With the genome of papaya (Carica papaya L.) sequenced, the study of gene function is becoming an increasing priority. Our research is to develop an RNA-induced gene silencing tool for the study of functional genomics in papaya. We employed agrobacterium leaf infiltration to induce PTGS in '-glucuro...

  20. Quantitative Genomics of Male Reproduction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of the review was to establish the current status of quantitative genomics for male reproduction. Genetic variation exists for male reproduction traits. These traits are expensive and time consuming traits to evaluate through conventional breeding schemes. Genomics is an alternative to...

  1. How Can Genomics Inform Education?

    ERIC Educational Resources Information Center

    Grigorenko, Elena L.

    2007-01-01

    This article offers some thoughts on possible connections between genomics and education. Genomics is already revolutionizing the way medical care is delivered and distributed; it will inevitably affect children's developmental trajectories by introducing more pharmacological and behavioral therapies. Educators should be prepared to understand the…

  2. Mycobacterium avium subsp. paratuberculosis Genome

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The completion of the MAP K-10 genome sequence has opened the doors to many new avenues of research. In the few years since the publication of the genome sequence, the manuscript describing the completed sequence has been cited in the scientific literature more than 85 times. The public availabili...

  3. Future Health Applications of Genomics

    PubMed Central

    McBride, Colleen M.; Bowen, Deborah; Brody, Lawrence C.; Condit, Celeste M.; Croyle, Robert T.; Gwinn, Marta; Khoury, Muin J.; Koehly, Laura M.; Korf, Bruce R.; Marteau, Theresa M.; McLeroy, Kenneth; Patrick, Kevin; Valente, Thomas W.

    2014-01-01

    Despite the quickening momentum of genomic discovery, the communication, behavioral, and social sciences research needed for translating this discovery into public health applications has lagged behind. The National Human Genome Research Institute held a 2-day workshop in October 2008 convening an interdisciplinary group of scientists to recommend forward-looking priorities for translational research. This research agenda would be designed to redress the top three risk factors (tobacco use, poor diet, and physical inactivity) that contribute to the four major chronic diseases (heart disease, type 2 diabetes, lung disease, and many cancers) and account for half of all deaths worldwide. Three priority research areas were identified: (1) improving the public’s genetic literacy in order to enhance consumer skills; (2) gauging whether genomic information improves risk communication and adoption of healthier behaviors more than current approaches; and (3) exploring whether genomic discovery in concert with emerging technologies can elucidate new behavioral intervention targets. Important crosscutting themes also were identified, including the need to: (1) anticipate directions of genomic discovery; (2) take an agnostic scientific perspective in framing research questions asking whether genomic discovery adds value to other health promotion efforts; and (3) consider multiple levels of influence and systems that contribute to important public health problems. The priorities and themes offer a framework for a variety of stakeholders, including those who develop priorities for research funding, interdisciplinary teams engaged in genomics research, and policymakers grappling with how to use the products born of genomics research to address public health challenges. PMID:20409503

  4. Big Data: Astronomical or Genomical?

    PubMed Central

    Stephens, Zachary D.; Lee, Skylar Y.; Faghri, Faraz; Campbell, Roy H.; Zhai, Chengxiang; Efron, Miles J.; Iyer, Ravishankar; Schatz, Michael C.; Sinha, Saurabh; Robinson, Gene E.

    2015-01-01

    Genomics is a Big Data science and is going to get much bigger, very soon, but it is not known whether the needs of genomics will exceed other Big Data domains. Projecting to the year 2025, we compared genomics with three other major generators of Big Data: astronomy, YouTube, and Twitter. Our estimates show that genomics is a “four-headed beast”—it is either on par with or the most demanding of the domains analyzed here in terms of data acquisition, storage, distribution, and analysis. We discuss aspects of new technologies that will need to be developed to rise up and meet the computational challenges that genomics poses for the near future. Now is the time for concerted, community-wide planning for the “genomical” challenges of the next decade. PMID:26151137

  5. Privacy in the Genomic Era

    PubMed Central

    NAVEED, MUHAMMAD; AYDAY, ERMAN; CLAYTON, ELLEN W.; FELLAY, JACQUES; GUNTER, CARL A.; HUBAUX, JEAN-PIERRE; MALIN, BRADLEY A.; WANG, XIAOFENG

    2015-01-01

    Genome sequencing technology has advanced at a rapid pace and it is now possible to generate highly-detailed genotypes inexpensively. The collection and analysis of such data has the potential to support various applications, including personalized medical services. While the benefits of the genomics revolution are trumpeted by the biomedical community, the increased availability of such data has major implications for personal privacy; notably because the genome has certain essential features, which include (but are not limited to) (i) an association with traits and certain diseases, (ii) identification capability (e.g., forensics), and (iii) revelation of family relationships. Moreover, direct-to-consumer DNA testing increases the likelihood that genome data will be made available in less regulated environments, such as the Internet and for-profit companies. The problem of genome data privacy thus resides at the crossroads of computer science, medicine, and public policy. While the computer scientists have addressed data privacy for various data types, there has been less attention dedicated to genomic data. Thus, the goal of this paper is to provide a systematization of knowledge for the computer science community. In doing so, we address some of the (sometimes erroneous) beliefs of this field and we report on a survey we conducted about genome data privacy with biomedical specialists. Then, after characterizing the genome privacy problem, we review the state-of-the-art regarding privacy attacks on genomic data and strategies for mitigating such attacks, as well as contextualizing these attacks from the perspective of medicine and public policy. This paper concludes with an enumeration of the challenges for genome data privacy and presents a framework to systematize the analysis of threats and the design of countermeasures as the field moves forward. PMID:26640318

  6. Recombination Drives Vertebrate Genome Contraction

    PubMed Central

    Nam, Kiwoong; Ellegren, Hans

    2012-01-01

    Selective and/or neutral processes may govern variation in DNA content and, ultimately, genome size. The observation in several organisms of a negative correlation between recombination rate and intron size could be compatible with a neutral model in which recombination is mutagenic for length changes. We used whole-genome data on small insertions and deletions within transposable elements from chicken and zebra finch to demonstrate clear links between recombination rate and a number of attributes of reduced DNA content. Recombination rate was negatively correlated with the length of introns, transposable elements, and intergenic spacer and with the rate of short insertions. Importantly, it was positively correlated with gene density, the rate of short deletions, the deletion bias, and the net change in sequence length. All these observations point at a pattern of more condensed genome structure in regions of high recombination. Based on the observed rates of small insertions and deletions and assuming that these rates are representative for the whole genome, we estimate that the genome of the most recent common ancestor of birds and lizards has lost nearly 20% of its DNA content up until the present. Expansion of transposable elements can counteract the effect of deletions in an equilibrium mutation model; however, since the activity of transposable elements has been low in the avian lineage, the deletion bias is likely to have had a significant effect on genome size evolution in dinosaurs and birds, contributing to the maintenance of a small genome. We also demonstrate that most of the observed correlations between recombination rate and genome contraction parameters are seen in the human genome, including for segregating indel polymorphisms. Our data are compatible with a neutral model in which recombination drives vertebrate genome size evolution and gives no direct support for a role of natural selection in this process. PMID:22570634

  7. RECORD: Reference-Assisted Genome Assembly for Closely Related Genomes

    PubMed Central

    Buza, Krisztian; Wilczynski, Bartek; Dojer, Norbert

    2015-01-01

    Background. Next-generation sequencing technologies are now producing multiple times the genome size in total reads from a single experiment. This is enough information to reconstruct at least some of the differences between the individual genome studied in the experiment and the reference genome of the species. However, in most typical protocols, this information is disregarded and the reference genome is used. Results. We provide a new approach that allows researchers to reconstruct genomes very closely related to the reference genome (e.g., mutants of the same species) directly from the reads used in the experiment. Our approach applies de novo assembly software to experimental reads and so-called pseudoreads and uses the resulting contigs to generate a modified reference sequence. In this way, it can very quickly, and at no additional sequencing cost, generate new, modified reference sequence that is closer to the actual sequenced genome and has a full coverage. In this paper, we describe our approach and test its implementation called RECORD. We evaluate RECORD on both simulated and real data. We made our software publicly available on sourceforge. Conclusion. Our tests show that on closely related sequences RECORD outperforms more general assisted-assembly software. PMID:26558255

  8. RECORD: Reference-Assisted Genome Assembly for Closely Related Genomes.

    PubMed

    Buza, Krisztian; Wilczynski, Bartek; Dojer, Norbert

    2015-01-01

    Background. Next-generation sequencing technologies are now producing multiple times the genome size in total reads from a single experiment. This is enough information to reconstruct at least some of the differences between the individual genome studied in the experiment and the reference genome of the species. However, in most typical protocols, this information is disregarded and the reference genome is used. Results. We provide a new approach that allows researchers to reconstruct genomes very closely related to the reference genome (e.g., mutants of the same species) directly from the reads used in the experiment. Our approach applies de novo assembly software to experimental reads and so-called pseudoreads and uses the resulting contigs to generate a modified reference sequence. In this way, it can very quickly, and at no additional sequencing cost, generate new, modified reference sequence that is closer to the actual sequenced genome and has a full coverage. In this paper, we describe our approach and test its implementation called RECORD. We evaluate RECORD on both simulated and real data. We made our software publicly available on sourceforge. Conclusion. Our tests show that on closely related sequences RECORD outperforms more general assisted-assembly software. PMID:26558255

  9. A Genome-Wide Landscape of Retrocopies in Primate Genomes

    PubMed Central

    Navarro, Fábio C.P.; Galante, Pedro A.F.

    2015-01-01

    Gene duplication is a key factor contributing to phenotype diversity across and within species. Although the availability of complete genomes has led to the extensive study of genomic duplications, the dynamics and variability of gene duplications mediated by retrotransposition are not well understood. Here, we predict mRNA retrotransposition and use comparative genomics to investigate their origin and variability across primates. Analyzing seven anthropoid primate genomes, we found a similar number of mRNA retrotranspositions (∼7,500 retrocopies) in Catarrhini (Old Word Monkeys, including humans), but a surprising large number of retrocopies (∼10,000) in Platyrrhini (New World Monkeys), which may be a by-product of higher long interspersed nuclear element 1 activity in these genomes. By inferring retrocopy orthology, we dated most of the primate retrocopy origins, and estimated a decrease in the fixation rate in recent primate history, implying a smaller number of species-specific retrocopies. Moreover, using RNA-Seq data, we identified approximately 3,600 expressed retrocopies. As expected, most of these retrocopies are located near or within known genes, present tissue-specific and even species-specific expression patterns, and no expression correlation to their parental genes. Taken together, our results provide further evidence that mRNA retrotransposition is an active mechanism in primate evolution and suggest that retrocopies may not only introduce great genetic variability between lineages but also create a large reservoir of potentially functional new genomic loci in primate genomes. PMID:26224704

  10. A Genome-Wide Landscape of Retrocopies in Primate Genomes.

    PubMed

    Navarro, Fábio C P; Galante, Pedro A F

    2015-08-01

    Gene duplication is a key factor contributing to phenotype diversity across and within species. Although the availability of complete genomes has led to the extensive study of genomic duplications, the dynamics and variability of gene duplications mediated by retrotransposition are not well understood. Here, we predict mRNA retrotransposition and use comparative genomics to investigate their origin and variability across primates. Analyzing seven anthropoid primate genomes, we found a similar number of mRNA retrotranspositions (∼7,500 retrocopies) in Catarrhini (Old Word Monkeys, including humans), but a surprising large number of retrocopies (∼10,000) in Platyrrhini (New World Monkeys), which may be a by-product of higher long interspersed nuclear element 1 activity in these genomes. By inferring retrocopy orthology, we dated most of the primate retrocopy origins, and estimated a decrease in the fixation rate in recent primate history, implying a smaller number of species-specific retrocopies. Moreover, using RNA-Seq data, we identified approximately 3,600 expressed retrocopies. As expected, most of these retrocopies are located near or within known genes, present tissue-specific and even species-specific expression patterns, and no expression correlation to their parental genes. Taken together, our results provide further evidence that mRNA retrotransposition is an active mechanism in primate evolution and suggest that retrocopies may not only introduce great genetic variability between lineages but also create a large reservoir of potentially functional new genomic loci in primate genomes. PMID:26224704

  11. Linking the genomes of nonmodel teleosts through comparative genomics.

    PubMed

    Sarropoulou, E; Nousdili, D; Magoulas, A; Kotoulas, G

    2008-01-01

    Recently the genomes of two more teleost species have been released: the medaka (Oryzias latipes), and the three-spined stickleback (Gasterosteus aculateus). The rapid developments in genomics of fish species paved the way to new and valuable research in comparative genetics and genomics. With the accumulation of information in model species, the genetic and genomic characterization of nonmodel, but economically important species, is now feasible. Furthermore, comparison of low coverage gene maps of aquacultured fish species against fully sequenced fish species will enhance the efficiency of candidate genes identification projected for quantitative trait loci (QTL) scans for traits of commercial interest. This study shows the syntenic relationship between the genomes of six different teleost species, including three fully sequenced model species: Tetraodon nigroviridis, Oryzias latipes, Gasterosteus aculateus, and three marine species of commercial and evolutionary interest: Sparus aurata, Dicentrarchus labrax, Oreochromis spp. All three commercial fish species belong to the order Perciformes, which is the richest in number of species (approximately 10,000) but poor in terms of available genomic information and tools. Syntenic relationships were established by using 800 EST and microsatellites sequences successfully mapped on the RH map of seabream. Comparison to the stickleback genome produced most positive BLAT hits (58%) followed by medaka (32%) and Tetraodon (30%). Thus, stickleback was used as the major stepping stone to compare seabass and tilapia to seabream. In addition to the significance for the aquaculture industry, this approach can encompass important ecological and evolutionary implications. PMID:18297360

  12. Integrated genome browser: visual analytics platform for genomics

    PubMed Central

    Norris, David C.; Loraine, Ann E.

    2016-01-01

    Motivation: Genome browsers that support fast navigation through vast datasets and provide interactive visual analytics functions can help scientists achieve deeper insight into biological systems. Toward this end, we developed Integrated Genome Browser (IGB), a highly configurable, interactive and fast open source desktop genome browser. Results: Here we describe multiple updates to IGB, including all-new capabilities to display and interact with data from high-throughput sequencing experiments. To demonstrate, we describe example visualizations and analyses of datasets from RNA-Seq, ChIP-Seq and bisulfite sequencing experiments. Understanding results from genome-scale experiments requires viewing the data in the context of reference genome annotations and other related datasets. To facilitate this, we enhanced IGB’s ability to consume data from diverse sources, including Galaxy, Distributed Annotation and IGB-specific Quickload servers. To support future visualization needs as new genome-scale assays enter wide use, we transformed the IGB codebase into a modular, extensible platform for developers to create and deploy all-new visualizations of genomic data. Availability and implementation: IGB is open source and is freely available from http://bioviz.org/igb. Contact: aloraine@uncc.edu PMID:27153568

  13. Unlocking hidden genomic sequence

    PubMed Central

    Keith, Jonathan M.; Cochran, Duncan A. E.; Lala, Gita H.; Adams, Peter; Bryant, Darryn; Mitchelson, Keith R.

    2004-01-01

    Despite the success of conventional Sanger sequencing, significant regions of many genomes still present major obstacles to sequencing. Here we propose a novel approach with the potential to alleviate a wide range of sequencing difficulties. The technique involves extracting target DNA sequence from variants generated by introduction of random mutations. The introduction of mutations does not destroy original sequence information, but distributes it amongst multiple variants. Some of these variants lack problematic features of the target and are more amenable to conventional sequencing. The technique has been successfully demonstrated with mutation levels up to an average 18% base substitution and has been used to read previously intractable poly(A), AT-rich and GC-rich motifs. PMID:14973330

  14. Genomics in Neurological Disorders

    PubMed Central

    Han, Guangchun; Sun, Jiya; Wang, Jiajia; Bai, Zhouxian; Song, Fuhai; Lei, Hongxing

    2014-01-01

    Neurological disorders comprise a variety of complex diseases in the central nervous system, which can be roughly classified as neurodegenerative diseases and psychiatric disorders. The basic and translational research of neurological disorders has been hindered by the difficulty in accessing the pathological center (i.e., the brain) in live patients. The rapid advancement of sequencing and array technologies has made it possible to investigate the disease mechanism and biomarkers from a systems perspective. In this review, recent progresses in the discovery of novel risk genes, treatment targets and peripheral biomarkers employing genomic technologies will be discussed. Our major focus will be on two of the most heavily investigated neurological disorders, namely Alzheimer’s disease and autism spectrum disorder. PMID:25108264

  15. Genomics of Atrial Fibrillation.

    PubMed

    Gutierrez, Alejandra; Chung, Mina K

    2016-06-01

    Atrial fibrillation (AF) is a common clinical arrhythmia that appears to be highly heritable, despite representing a complex interplay of several disease processes that generally do not manifest until later in life. In this manuscript, we will review the genetic basis of this complex trait established through studies of familial AF, linkage and candidate gene studies of common AF, genome wide association studies (GWAS) of common AF, and transcriptomic studies of AF. Since AF is associated with a five-fold increase in the risk of stroke, we also review the intersection of common genetic factors associated with both of these conditions. Similarly, we highlight the intersection of common genetic markers associated with some risk factors for AF, such as hypertension and obesity, and AF. Lastly, we describe a paradigm where genetic factors predispose to the risk of AF, but which may require additional stress and trigger factors in older age to allow for the clinical manifestation of AF. PMID:27139902

  16. Genome patent fight erupts

    SciTech Connect

    Roberts, L.

    1991-10-11

    At a Congressional briefing while describing a new project to sequence partially every gene active in the human brain, it was made known that the National Institutes of Health was planning to file patent applications on 1,000 of these sequences a month. The scheme has engendered a firestorm of criticism from genome scientists and project officials alike. The critics argue that these sequences probably can't be patented in the first place - and even if they can, they shouldn't be. The plan would undercut patent protection for those who labor long and hard at the real task of elucidating the function of the proteins encoded by the genes, thereby driving industry away from developing inventions based on that work.

  17. The South Asian Genome

    PubMed Central

    Scott, William R.; Tan, Sian-Tsung; Afzal, Uzma; Afaq, Saima; Loh, Marie; Lehne, Benjamin; O'Reilly, Paul; Gaulton, Kyle J.; Pearson, Richard D.; Li, Xinzhong; Lavery, Anita; Vandrovcova, Jana; Wass, Mark N.; Miller, Kathryn; Sehmi, Joban; Oozageer, Laticia; Kooner, Ishminder K.; Al-Hussaini, Abtehale; Mills, Rebecca; Grewal, Jagvir; Panoulas, Vasileios; Lewin, Alexandra M.; Northwood, Korrinne; Wander, Gurpreet S.; Geoghegan, Frank; Li, Yingrui; Wang, Jun; Aitman, Timothy J.; McCarthy, Mark I.

    2014-01-01

    The genetic sequence variation of people from the Indian subcontinent who comprise one-quarter of the world's population, is not well described. We carried out whole genome sequencing of 168 South Asians, along with whole-exome sequencing of 147 South Asians to provide deeper characterisation of coding regions. We identify 12,962,155 autosomal sequence variants, including 2,946,861 new SNPs and 312,738 novel indels. This catalogue of SNPs and indels amongst South Asians provides the first comprehensive map of genetic variation in this major human population, and reveals evidence for selective pressures on genes involved in skin biology, metabolism, infection and immunity. Our results will accelerate the search for the genetic variants underlying susceptibility to disorders such as type-2 diabetes and cardiovascular disease which are highly prevalent amongst South Asians. PMID:25115870

  18. Plantagora: Modeling Whole Genome Sequencing and Assembly of Plant Genomes

    PubMed Central

    Barthelson, Roger; McFarlin, Adam J.; Rounsley, Steven D.; Young, Sarah

    2011-01-01

    Background Genomics studies are being revolutionized by the next generation sequencing technologies, which have made whole genome sequencing much more accessible to the average researcher. Whole genome sequencing with the new technologies is a developing art that, despite the large volumes of data that can be produced, may still fail to provide a clear and thorough map of a genome. The Plantagora project was conceived to address specifically the gap between having the technical tools for genome sequencing and knowing precisely the best way to use them. Methodology/Principal Findings For Plantagora, a platform was created for generating simulated reads from several different plant genomes of different sizes. The resulting read files mimicked either 454 or Illumina reads, with varying paired end spacing. Thousands of datasets of reads were created, most derived from our primary model genome, rice chromosome one. All reads were assembled with different software assemblers, including Newbler, Abyss, and SOAPdenovo, and the resulting assemblies were evaluated by an extensive battery of metrics chosen for these studies. The metrics included both statistics of the assembly sequences and fidelity-related measures derived by alignment of the assemblies to the original genome source for the reads. The results were presented in a website, which includes a data graphing tool, all created to help the user compare rapidly the feasibility and effectiveness of different sequencing and assembly strategies prior to testing an approach in the lab. Some of our own conclusions regarding the different strategies were also recorded on the website. Conclusions/Significance Plantagora provides a substantial body of information for comparing different approaches to sequencing a plant genome, and some conclusions regarding some of the specific approaches. Plantagora also provides a platform of metrics and tools for studying the process of sequencing and assembly further. PMID:22174807

  19. Microbial Genomics Data from the DOE Joint Genome Institute (JGI)

    DOE Data Explorer

    The JGI makes high-quality genome sequencing data freely available to the greater scientific community through its web portal. Having played a significant role in the federally funded Human Genome Project -- generating the complete sequences of Chromosomes 5, 16, and 19--the JGI has now moved on to contributing in other critical areas of genomics research. While NIH-funded genome sequencing activities continue to emphasize human biomedical targets and applications, the JGI has since shifted its focus to the non-human components of the biosphere, particularly those relevant to the science mission of the Department of Energy. With efficiencies of scale established at the PGF, and capacity now exceeding three billion bases generated on a monthly basis, the JGI has tackled scores of additional genomes. These include more than 60 microbial genomes and many important multicellular organisms and communities of microbes. In partnership with other federal institutions and universities, the JGI is in the process of sequencing a frog (Xenopus tropicalis), a green alga (Chlamydomonas reinhardtii), a diatom (Thalassiosira pseudonana) , the cottonwood tree (Populus trichocarpa), and a host of agriculturally important plants and plant pathogens. Microorganisms, for example those that thrive under extreme conditions such as high acidity, radiation, and metal contamination, are of particular interest to the DOE and JGI. Investigations by JGI and its partners are shedding light on the cellular machinery of microbes and how they can be harnessed to clean up contaminated soil or water, capture carbon from the atmosphere, and produce potentially important sources of energy such as hydrogen and methane. [Excerpt from the JGI page "Who We Are" at http://www.jgi.doe.gov/whoweare/whoweare.html] From the JGI webportal users can view a photo grid of organisims, check assemblies for status, access the Integrated Microbial Genomes (IMG) system to do comparative analysis of publicly available

  20. Insights into conifer giga-genomes.

    PubMed

    De La Torre, Amanda R; Birol, Inanc; Bousquet, Jean; Ingvarsson, Pär K; Jansson, Stefan; Jones, Steven J M; Keeling, Christopher I; MacKay, John; Nilsson, Ove; Ritland, Kermit; Street, Nathaniel; Yanchuk, Alvin; Zerbe, Philipp; Bohlmann, Jörg

    2014-12-01

    Insights from sequenced genomes of major land plant lineages have advanced research in almost every aspect of plant biology. Until recently, however, assembled genome sequences of gymnosperms have been missing from this picture. Conifers of the pine family (Pinaceae) are a group of gymnosperms that dominate large parts of the world's forests. Despite their ecological and economic importance, conifers seemed long out of reach for complete genome sequencing, due in part to their enormous genome size (20-30 Gb) and the highly repetitive nature of their genomes. Technological advances in genome sequencing and assembly enabled the recent publication of three conifer genomes: white spruce (Picea glauca), Norway spruce (Picea abies), and loblolly pine (Pinus taeda). These genome sequences revealed distinctive features compared with other plant genomes and may represent a window into the past of seed plant genomes. This Update highlights recent advances, remaining challenges, and opportunities in light of the publication of the first conifer and gymnosperm genomes. PMID:25349325

  1. Jumbled genomes: missing Apicomplexan synteny.

    PubMed

    DeBarry, Jeremy D; Kissinger, Jessica C

    2011-10-01

    Whole-genome comparisons provide insight into genome evolution by informing on gene repertoires, gene gains/losses, and genome organization. Most of our knowledge about eukaryotic genome evolution is derived from studies of multicellular model organisms. The eukaryotic phylum Apicomplexa contains obligate intracellular protist parasites responsible for a wide range of human and veterinary diseases (e.g., malaria, toxoplasmosis, and theileriosis). We have developed an in silico protein-encoding gene based pipeline to investigate synteny across 12 apicomplexan species from six genera. Genome rearrangement between lineages is extensive. Syntenic regions (conserved gene content and order) are rare between lineages and appear to be totally absent across the phylum, with no group of three genes found on the same chromosome and in the same order within 25 kb up- and downstream of any orthologous genes. Conserved synteny between major lineages is limited to small regions in Plasmodium and Theileria/Babesia species, and within these conserved regions, there are a number of proteins putatively targeted to organelles. The observed overall lack of synteny is surprising considering the divergence times and the apparent absence of transposable elements (TEs) within any of the species examined. TEs are ubiquitous in all other groups of eukaryotes studied to date and have been shown to be involved in genomic rearrangements. It appears that there are different criteria governing genome evolution within the Apicomplexa relative to other well-studied unicellular and multicellular eukaryotes. PMID:21504890

  2. The genome of Eucalyptus grandis

    SciTech Connect

    Myburg, Alexander A.; Grattapaglia, Dario; Tuskan, Gerald A.; Hellsten, Uffe; Hayes, Richard D.; Grimwood, Jane; Jenkins, Jerry; Lindquist, Erika; Tice, Hope; Bauer, Diane; Goodstein, David M.; Dubchak, Inna; Poliakov, Alexandre; Mizrachi, Eshchar; Kullan, Anand R. K.; Hussey, Steven G.; Pinard, Desre; van der Merwe, Karen; Singh, Pooja; van Jaarsveld, Ida; Silva-Junior, Orzenil B.; Togawa, Roberto C.; Pappas, Marilia R.; Faria, Danielle A.; Sansaloni, Carolina P.; Petroli, Cesar D.; Yang, Xiaohan; Ranjan, Priya; Tschaplinski, Timothy J.; Ye, Chu-Yu; Li, Ting; Sterck, Lieven; Vanneste, Kevin; Murat, Florent; Soler, Marçal; Clemente, Hélène San; Saidi, Naijib; Cassan-Wang, Hua; Dunand, Christophe; Hefer, Charles A.; Bornberg-Bauer, Erich; Kersting, Anna R.; Vining, Kelly; Amarasinghe, Vindhya; Ranik, Martin; Naithani, Sushma; Elser, Justin; Boyd, Alexander E.; Liston, Aaron; Spatafora, Joseph W.; Dharmwardhana, Palitha; Raja, Rajani; Sullivan, Christopher; Romanel, Elisson; Alves-Ferreira, Marcio; Külheim, Carsten; Foley, William; Carocha, Victor; Paiva, Jorge; Kudrna, David; Brommonschenkel, Sergio H.; Pasquali, Giancarlo; Byrne, Margaret; Rigault, Philippe; Tibbits, Josquin; Spokevicius, Antanas; Jones, Rebecca C.; Steane, Dorothy A.; Vaillancourt, René E.; Potts, Brad M.; Joubert, Fourie; Barry, Kerrie; Pappas, Georgios J.; Strauss, Steven H.; Jaiswal, Pankaj; Grima-Pettenati, Jacqueline; Salse, Jérôme; Van de Peer, Yves; Rokhsar, Daniel S.; Schmutz, Jeremy

    2014-06-11

    Eucalypts are the world s most widely planted hardwood trees. Their broad adaptability, rich species diversity, fast growth and superior multipurpose wood, have made them a global renewable resource of fiber and energy that mitigates human pressures on natural forests. We sequenced and assembled >94% of the 640 Mbp genome of Eucalyptus grandis into its 11 chromosomes. A set of 36,376 protein coding genes were predicted revealing that 34% occur in tandem duplications, the largest proportion found thus far in any plant genome. Eucalypts also show the highest diversity of genes for plant specialized metabolism that act as chemical defence against biotic agents and provide unique pharmaceutical oils. Resequencing of a set of inbred tree genomes revealed regions of strongly conserved heterozygosity, likely hotspots of inbreeding depression. The resequenced genome of the sister species E. globulus underscored the high inter-specific genome colinearity despite substantial genome size variation in the genus. The genome of E. grandis is the first reference for the early diverging Rosid order Myrtales and is placed here basal to the Eurosids. This resource expands knowledge on the unique biology of large woody perennials and provides a powerful tool to accelerate comparative biology, breeding and biotechnology.

  3. Genomics in the ecological arena.

    PubMed

    Orsini, Luisa; Decaestecker, Ellen; De Meester, Luc; Pfrender, Michael E; Colbourne, John K

    2011-02-23

    This meeting report presents the cutting-edge research that is developing around the waterflea Daphnia, an emerging model system in environmental genomics. Daphnia has been a model species in ecology, toxicology and evolution for many years and is supported by a large community of ecologists, evolutionary biologists and ecotoxicologists. Thanks to new advances in genomics and transciptomics and to the sustained efforts of the Daphnia Genomics Consortium (DGC), Daphnia is also rapidly developing as a model system in environmental genomics. Advances in this emerging field were presented at the DGC 2010, held for the first time in a European University. During the meeting, a plethora of elegant studies were presented on the mechanisms of responses to environmental challenges using recently developed genomic tools. The DGC 2010 is a concrete example of the new trends in ecology and evolution. The times are mature for the application of innovative genomic and transcriptomic tools for studies of environmental genomics in non-model organisms. PMID:20702453

  4. Clinical genomics: from a truly personal genome viewpoint.

    PubMed

    Lupski, James R

    2016-06-01

    The path to Clinical Genomics is punctuated by our understanding of what types of DNA structural and sequence variation contribute to disease, the many technical challenges to detect such variation genome-wide, and the initial struggles to interpret personal genome variation in the context of disease. This review describes one perspective of the development of clinical genomics; whereas the experimental challenges, and hurdles to overcoming them, might be deemed readily apparent, the non-technical issues for clinical implementation may be less obvious. Some of these latter challenges, including: (1) informed consent, (2) privacy, (3) what constitutes potentially pathogenic variation contributing to disease, (4) disease penetrance in populations, and (5) the genetic architecture of disease, and the struggles sometimes faced for solutions, are highlighted using illustrative examples. PMID:27221143

  5. Comparative genomics reveals insights into avian genome evolution and adaptation

    PubMed Central

    Zhang, Guojie; Li, Cai; Li, Qiye; Li, Bo; Larkin, Denis M.; Lee, Chul; Storz, Jay F.; Antunes, Agostinho; Greenwold, Matthew J.; Meredith, Robert W.; Ödeen, Anders; Cui, Jie; Zhou, Qi; Xu, Luohao; Pan, Hailin; Wang, Zongji; Jin, Lijun; Zhang, Pei; Hu, Haofu; Yang, Wei; Hu, Jiang; Xiao, Jin; Yang, Zhikai; Liu, Yang; Xie, Qiaolin; Yu, Hao; Lian, Jinmin; Wen, Ping; Zhang, Fang; Li, Hui; Zeng, Yongli; Xiong, Zijun; Liu, Shiping; Zhou, Long; Huang, Zhiyong; An, Na; Wang, Jie; Zheng, Qiumei; Xiong, Yingqi; Wang, Guangbiao; Wang, Bo; Wang, Jingjing; Fan, Yu; da Fonseca, Rute R.; Alfaro-Núñez, Alonzo; Schubert, Mikkel; Orlando, Ludovic; Mourier, Tobias; Howard, Jason T.; Ganapathy, Ganeshkumar; Pfenning, Andreas; Whitney, Osceola; Rivas, Miriam V.; Hara, Erina; Smith, Julia; Farré, Marta; Narayan, Jitendra; Slavov, Gancho; Romanov, Michael N; Borges, Rui; Machado, João Paulo; Khan, Imran; Springer, Mark S.; Gatesy, John; Hoffmann, Federico G.; Opazo, Juan C.; Håstad, Olle; Sawyer, Roger H.; Kim, Heebal; Kim, Kyu-Won; Kim, Hyeon Jeong; Cho, Seoae; Li, Ning; Huang, Yinhua; Bruford, Michael W.; Zhan, Xiangjiang; Dixon, Andrew; Bertelsen, Mads F.; Derryberry, Elizabeth; Warren, Wesley; Wilson, Richard K; Li, Shengbin; Ray, David A.; Green, Richard E.; O’Brien, Stephen J.; Griffin, Darren; Johnson, Warren E.; Haussler, David; Ryder, Oliver A.; Willerslev, Eske; Graves, Gary R.; Alström, Per; Fjeldså, Jon; Mindell, David P.; Edwards, Scott V.; Braun, Edward L.; Rahbek, Carsten; Burt, David W.; Houde, Peter; Zhang, Yong; Yang, Huanming; Wang, Jian; Jarvis, Erich D.; Gilbert, M. Thomas P.; Wang, Jun

    2015-01-01

    Birds are the most species-rich class of tetrapod vertebrates and have wide relevance across many research fields. We explored bird macroevolution using full genomes from 48 avian species representing all major extant clades. The avian genome is principally characterized by its constrained size, which predominantly arose because of lineage-specific erosion of repetitive elements, large segmental deletions, and gene loss. Avian genomes furthermore show a remarkably high degree of evolutionary stasis at the levels of nucleotide sequence, gene synteny, and chromosomal structure. Despite this pattern of conservation, we detected many non-neutral evolutionary changes in protein-coding genes and noncoding regions. These analyses reveal that pan-avian genomic diversity covaries with adaptations to different lifestyles and convergent evolution of traits. PMID:25504712

  6. Orthology for comparative genomics in the mouse genome database.

    PubMed

    Dolan, Mary E; Baldarelli, Richard M; Bello, Susan M; Ni, Li; McAndrews, Monica S; Bult, Carol J; Kadin, James A; Richardson, Joel E; Ringwald, Martin; Eppig, Janan T; Blake, Judith A

    2015-08-01

    The mouse genome database (MGD) is the model organism database component of the mouse genome informatics system at The Jackson Laboratory. MGD is the international data resource for the laboratory mouse and facilitates the use of mice in the study of human health and disease. Since its beginnings, MGD has included comparative genomics data with a particular focus on human-mouse orthology, an essential component of the use of mouse as a model organism. Over the past 25 years, novel algorithms and addition of orthologs from other model organisms have enriched comparative genomics in MGD data, extending the use of orthology data to support the laboratory mouse as a model of human biology. Here, we describe current comparative data in MGD and review the history and refinement of orthology representation in this resource. PMID:26223881

  7. Applied genomics: Tools ranging from genomic prediction to bioconservation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This invited presentation will provide an overview of the development of genomic tools in cattle and goats, and how these approaches and methodologies can be adapted for bioconservation of endangered ruminant species....

  8. Genome Modeling System: A Knowledge Management Platform for Genomics

    PubMed Central

    Griffith, Malachi; Griffith, Obi L.; Smith, Scott M.; Ramu, Avinash; Callaway, Matthew B.; Brummett, Anthony M.; Kiwala, Michael J.; Coffman, Adam C.; Regier, Allison A.; Oberkfell, Ben J.; Sanderson, Gabriel E.; Mooney, Thomas P.; Nutter, Nathaniel G.; Belter, Edward A.; Du, Feiyu; Long, Robert L.; Abbott, Travis E.; Ferguson, Ian T.; Morton, David L.; Burnett, Mark M.; Weible, James V.; Peck, Joshua B.; Dukes, Adam; McMichael, Joshua F.; Lolofie, Justin T.; Derickson, Brian R.; Hundal, Jasreet; Skidmore, Zachary L.; Ainscough, Benjamin J.; Dees, Nathan D.; Schierding, William S.; Kandoth, Cyriac; Kim, Kyung H.; Lu, Charles; Harris, Christopher C.; Maher, Nicole; Maher, Christopher A.; Magrini, Vincent J.; Abbott, Benjamin S.; Chen, Ken; Clark, Eric; Das, Indraniel; Fan, Xian; Hawkins, Amy E.; Hepler, Todd G.; Wylie, Todd N.; Leonard, Shawn M.; Schroeder, William E.; Shi, Xiaoqi; Carmichael, Lynn K.; Weil, Matthew R.; Wohlstadter, Richard W.; Stiehr, Gary; McLellan, Michael D.; Pohl, Craig S.; Miller, Christopher A.; Koboldt, Daniel C.; Walker, Jason R.; Eldred, James M.; Larson, David E.; Dooling, David J.; Ding, Li; Mardis, Elaine R.; Wilson, Richard K.

    2015-01-01

    In this work, we present the Genome Modeling System (GMS), an analysis information management system capable of executing automated genome analysis pipelines at a massive scale. The GMS framework provides detailed tracking of samples and data coupled with reliable and repeatable analysis pipelines. The GMS also serves as a platform for bioinformatics development, allowing a large team to collaborate on data analysis, or an individual researcher to leverage the work of others effectively within its data management system. Rather than separating ad-hoc analysis from rigorous, reproducible pipelines, the GMS promotes systematic integration between the two. As a demonstration of the GMS, we performed an integrated analysis of whole genome, exome and transcriptome sequencing data from a breast cancer cell line (HCC1395) and matched lymphoblastoid line (HCC1395BL). These data are available for users to test the software, complete tutorials and develop novel GMS pipeline configurations. The GMS is available at https://github.com/genome/gms. PMID:26158448

  9. Comparative genomics reveals insights into avian genome evolution and adaptation.

    PubMed

    Zhang, Guojie; Li, Cai; Li, Qiye; Li, Bo; Larkin, Denis M; Lee, Chul; Storz, Jay F; Antunes, Agostinho; Greenwold, Matthew J; Meredith, Robert W; Ödeen, Anders; Cui, Jie; Zhou, Qi; Xu, Luohao; Pan, Hailin; Wang, Zongji; Jin, Lijun; Zhang, Pei; Hu, Haofu; Yang, Wei; Hu, Jiang; Xiao, Jin; Yang, Zhikai; Liu, Yang; Xie, Qiaolin; Yu, Hao; Lian, Jinmin; Wen, Ping; Zhang, Fang; Li, Hui; Zeng, Yongli; Xiong, Zijun; Liu, Shiping; Zhou, Long; Huang, Zhiyong; An, Na; Wang, Jie; Zheng, Qiumei; Xiong, Yingqi; Wang, Guangbiao; Wang, Bo; Wang, Jingjing; Fan, Yu; da Fonseca, Rute R; Alfaro-Núñez, Alonzo; Schubert, Mikkel; Orlando, Ludovic; Mourier, Tobias; Howard, Jason T; Ganapathy, Ganeshkumar; Pfenning, Andreas; Whitney, Osceola; Rivas, Miriam V; Hara, Erina; Smith, Julia; Farré, Marta; Narayan, Jitendra; Slavov, Gancho; Romanov, Michael N; Borges, Rui; Machado, João Paulo; Khan, Imran; Springer, Mark S; Gatesy, John; Hoffmann, Federico G; Opazo, Juan C; Håstad, Olle; Sawyer, Roger H; Kim, Heebal; Kim, Kyu-Won; Kim, Hyeon Jeong; Cho, Seoae; Li, Ning; Huang, Yinhua; Bruford, Michael W; Zhan, Xiangjiang; Dixon, Andrew; Bertelsen, Mads F; Derryberry, Elizabeth; Warren, Wesley; Wilson, Richard K; Li, Shengbin; Ray, David A; Green, Richard E; O'Brien, Stephen J; Griffin, Darren; Johnson, Warren E; Haussler, David; Ryder, Oliver A; Willerslev, Eske; Graves, Gary R; Alström, Per; Fjeldså, Jon; Mindell, David P; Edwards, Scott V; Braun, Edward L; Rahbek, Carsten; Burt, David W; Houde, Peter; Zhang, Yong; Yang, Huanming; Wang, Jian; Jarvis, Erich D; Gilbert, M Thomas P; Wang, Jun

    2014-12-12

    Birds are the most species-rich class of tetrapod vertebrates and have wide relevance across many research fields. We explored bird macroevolution using full genomes from 48 avian species representing all major extant clades. The avian genome is principally characterized by its constrained size, which predominantly arose because of lineage-specific erosion of repetitive elements, large segmental deletions, and gene loss. Avian genomes furthermore show a remarkably high degree of evolutionary stasis at the levels of nucleotide sequence, gene synteny, and chromosomal structure. Despite this pattern of conservation, we detected many non-neutral evolutionary changes in protein-coding genes and noncoding regions. These analyses reveal that pan-avian genomic diversity covaries with adaptations to different lifestyles and convergent evolution of traits. PMID:25504712

  10. Behavior, Brain, and Genome in Genomic Disorders: Finding the Correspondences

    PubMed Central

    Grigorenko, Elena L.; Urban, Alexander E.; Mencl, Einar

    2014-01-01

    Objective Within the last decade or so, there has been an acceleration of research attempting to connect specific genetic lesions to patterns of brain structure and activation. This article comments on observations that have been made based on these recent data and discusses their importance for the field of investigations into developmental disorders. Method In making these observations, we focus on one specific genomic lesion, the well-studied, yet still incompletely understood, 22q11.2 deletion syndrome (22q11.2DS). Results We demonstrate the degree of variability in the phenotype that occurs at both the brain and behavioral levels of genomic disorders, and describe how this variability is, upon close inspection, represented at the genomic level. Conclusion We emphasize the importance of combining genetic/genomic analyses and neuroimaging for research and for future clinical diagnostic purposes, and for the purposes of developing individualized, patient-tailored treatment and remediation approaches. PMID:20814258

  11. In quest of genomic treasure

    PubMed Central

    INOUE, Kimiko; OGURA, Atsuo

    2015-01-01

    It should be emphasized that “129” is not simply a number but is also the designation of a mouse strain that has made a great contribution to modern biological science and technology. Embryonic stem cells derived from 129 mice were essential components of gene-targeting strategies in early research. More recently, 129 mice have provided superior donor genomes for cloning by nuclear transfer. Some factor or factors conferring genomic plasticity must exist in the 129 genome, but these remain unidentified. PMID:26400375

  12. Human genome. 1993 Program report

    SciTech Connect

    Not Available

    1994-03-01

    The purpose of this report is to update the Human Genome 1991-92 Program Report and provide new information on the DOE genome program to researchers, program managers, other government agencies, and the interested public. This FY 1993 supplement includes abstracts of 60 new or renewed projects and listings of 112 continuing and 28 completed projects. These two reports, taken together, present the most complete published view of the DOE Human Genome Program through FY 1993. Research is progressing rapidly toward 15-year goals of mapping and sequencing the DNA of each of the 24 different human chromosomes.

  13. Challenges in Whole-Genome Annotation of Pyrosequenced Eukaryotic Genomes

    SciTech Connect

    Kuo, Alan; Grigoriev, Igor

    2009-04-17

    Pyrosequencing technologies such as 454/Roche and Solexa/Illumina vastly lower the cost of nucleotide sequencing compared to the traditional Sanger method, and thus promise to greatly expand the number of sequenced eukaryotic genomes. However, the new technologies also bring new challenges such as shorter reads and new kinds and higher rates of sequencing errors, which complicate genome assembly and gene prediction. At JGI we are deploying 454 technology for the sequencing and assembly of ever-larger eukaryotic genomes. Here we describe our first whole-genome annotation of a purely 454-sequenced fungal genome that is larger than a yeast (>30 Mbp). The pezizomycotine (filamentous ascomycote) Aspergillus carbonarius belongs to the Aspergillus section Nigri species complex, members of which are significant as platforms for bioenergy and bioindustrial technology, as members of soil microbial communities and players in the global carbon cycle, and as agricultural toxigens. Application of a modified version of the standard JGI Annotation Pipeline has so far predicted ~;;10k genes. ~;;12percent of these preliminary annotations suffer a potential frameshift error, which is somewhat higher than the ~;;9percent rate in the Sanger-sequenced and conventionally assembled and annotated genome of fellow Aspergillus section Nigri member A. niger. Also,>90percent of A. niger genes have potential homologs in the A. carbonarius preliminary annotation. Weconclude, and with further annotation and comparative analysis expect to confirm, that 454 sequencing strategies provide a promising substrate for annotation of modestly sized eukaryotic genomes. We will also present results of annotation of a number of other pyrosequenced fungal genomes of bioenergy interest.

  14. Radiation Induced Genomic Instability

    SciTech Connect

    Morgan, William F.

    2011-03-01

    Radiation induced genomic instability can be observed in the progeny of irradiated cells multiple generations after irradiation of parental cells. The phenotype is well established both in vivo (Morgan 2003) and in vitro (Morgan 2003), and may be critical in radiation carcinogenesis (Little 2000, Huang et al. 2003). Instability can be induced by both the deposition of energy in irradiated cells as well as by signals transmitted by irradiated (targeted) cells to non-irradiated (non-targeted) cells (Kadhim et al. 1992, Lorimore et al. 1998). Thus both targeted and non-targeted cells can pass on the legacy of radiation to their progeny. However the radiation induced events and cellular processes that respond to both targeted and non-targeted radiation effects that lead to the unstable phenotype remain elusive. The cell system we have used to study radiation induced genomic instability utilizes human hamster GM10115 cells. These cells have a single copy of human chromosome 4 in a background of hamster chromosomes. Instability is evaluated in the clonal progeny of irradiated cells and a clone is considered unstable if it contains three or more metaphase sub-populations involving unique rearrangements of the human chromosome (Marder and Morgan 1993). Many of these unstable clones have been maintained in culture for many years and have been extensively characterized. As initially described by Clutton et al., (Clutton et al. 1996) many of our unstable clones exhibit persistently elevated levels of reactive oxygen species (Limoli et al. 2003), which appear to be due dysfunctional mitochondria (Kim et al. 2006, Kim et al. 2006). Interestingly, but perhaps not surprisingly, our unstable clones do not demonstrate a “mutator phenotype” (Limoli et al. 1997), but they do continue to rearrange their genomes for many years. The limiting factor with this system is the target – the human chromosome. While some clones demonstrate amplification of this chromosome and thus lend

  15. Archaic human genomics.

    PubMed

    Disotell, Todd R

    2012-01-01

    For much of the 20th century, the predominant view of human evolutionary history was derived from the fossil record. Homo erectus was seen arising in Africa from an earlier member of the genus and then spreading throughout the Old World and into the Oceania. A regional continuity model of anagenetic change from H. erectus via various intermediate archaic species into the modern humans in each of the regions inhabited by H. erectus was labeled the multiregional model of human evolution (MRE). A contrasting model positing a single origin, in Africa, of anatomically modern H. sapiens with some populations later migrating out of Africa and replacing the local archaic populations throughout the world with complete replacement became known as the recent African origin (RAO) model. Proponents of both models used different interpretations of the fossil record to bolster their views for decades. In the 1980s, molecular genetic techniques began providing evidence from modern human variation that allowed not only the different models of modern human origins to be tested but also the exploration demographic history and the types of selection that different regions of the genome and even specific traits had undergone. The majority of researchers interpreted these data as strongly supporting the RAO model, especially analyses of mitochondrial DNA (mtDNA). Extrapolating backward from modern patterns of variation and using various calibration points and substitution rates, a consensus arose that saw modern humans evolving from an African population around 200,000 years ago. Much later, around 50,000 years ago, a subset of this population migrated out of Africa replacing Neanderthals in Europe and western Asia as well as archaics in eastern Asia and Oceania. mtDNA sequences from more than two-dozen Neanderthals and early modern humans re-enforced this consensus. In 2010, however, the complete draft genomes of Neanderthals and of heretofore unknown hominins from Siberia, called

  16. The Materials Genome Project

    NASA Astrophysics Data System (ADS)

    Aourag, H.

    2008-09-01

    In the past, the search for new and improved materials was characterized mostly by the use of empirical, trial- and-error methods. This picture of materials science has been changing as the knowledge and understanding of fundamental processes governing a material's properties and performance (namely, composition, structure, history, and environment) have increased. In a number of cases, it is now possible to predict a material's properties before it has even been manufactured thus greatly reducing the time spent on testing and development. The objective of modern materials science is to tailor a material (starting with its chemical composition, constituent phases, and microstructure) in order to obtain a desired set of properties suitable for a given application. In the short term, the traditional "empirical" methods for developing new materials will be complemented to a greater degree by theoretical predictions. In some areas, computer simulation is already used by industry to weed out costly or improbable synthesis routes. Can novel materials with optimized properties be designed by computers? Advances in modelling methods at the atomic level coupled with rapid increases in computer capabilities over the last decade have led scientists to answer this question with a resounding "yes'. The ability to design new materials from quantum mechanical principles with computers is currently one of the fastest growing and most exciting areas of theoretical research in the world. The methods allow scientists to evaluate and prescreen new materials "in silico" (in vitro), rather than through time consuming experimentation. The Materials Genome Project is to pursue the theory of large scale modeling as well as powerful methods to construct new materials, with optimized properties. Indeed, it is the intimate synergy between our ability to predict accurately from quantum theory how atoms can be assembled to form new materials and our capacity to synthesize novel materials atom

  17. Sequencing and mapping of the onion genome

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The cost of DNA sequencing continues to decline and, in the near future, it will become reasonable to undertake sequencing of the enormous nuclear genome of onion. We undertook sequencing of expressed and genomic regions of the onion genome to learn about the structure of the onion genome, as well a...

  18. Genomic Aspects of Research Involving Polyploid Plants

    SciTech Connect

    Yang, Xiaohan; Ye, Chuyu; Tschaplinski, Timothy J; Wullschleger, Stan D; Tuskan, Gerald A

    2011-01-01

    Almost all extant plant species have spontaneously doubled their genomes at least once in their evolutionary histories, resulting in polyploidy which provided a rich genomic resource for evolutionary processes. Moreover, superior polyploid clones have been created during the process of crop domestication. Polyploid plants generated by evolutionary processes and/or crop domestication have been the intentional or serendipitous focus of research dealing with the dynamics and consequences of genome evolution. One of the new trends in genomics research is to create synthetic polyploid plants which provide materials for studying the initial genomic changes/responses immediately after polyploid formation. Polyploid plants are also used in functional genomics research to study gene expression in a complex genomic background. In this review, we summarize the recent progress in genomics research involving ancient, young, and synthetic polyploid plants, with a focus on genome size evolution, genomics diversity, genomic rearrangement, genetic and epigenetic changes in duplicated genes, gene discovery, and comparative genomics. Implications on plant sciences including evolution, functional genomics, and plant breeding are presented. It is anticipated that polyploids will be a regular subject of genomics research in the foreseeable future as the rapid advances in DNA sequencing technology create unprecedented opportunities for discovering and monitoring genomic and transcriptomic changes in polyploid plants. The fast accumulation of knowledge on polyploid formation, maintenance, and divergence at whole-genome and subgenome levels will not only help plant biologists understand how plants have evolved and diversified, but also assist plant breeders in designing new strategies for crop improvement.

  19. 2004 Structural, Function and Evolutionary Genomics

    SciTech Connect

    Douglas L. Brutlag Nancy Ryan Gray

    2005-03-23

    This Gordon conference will cover the areas of structural, functional and evolutionary genomics. It will take a systematic approach to genomics, examining the evolution of proteins, protein functional sites, protein-protein interactions, regulatory networks, and metabolic networks. Emphasis will be placed on what we can learn from comparative genomics and entire genomes and proteomes.

  20. Meeting Highlights: Genome Sequencing and Biology 2001

    PubMed Central

    2001-01-01

    We bring you a report from the CSHL Genome Sequencing and Biology Meeting, which has a long and prestigious history. This year there were sessions on large-scale sequencing and analysis, polymorphisms (covering discovery and technologies and mapping and analysis), comparative genomics of mammalian and model organism genomes, functional genomics and bioinformatics. PMID:18628920

  1. Reannotation of Shewanella oneidensis genome.

    PubMed

    Daraselia, N; Dernovoy, D; Tian, Y; Borodovsky, M; Tatusov, R; Tatusova, T

    2003-01-01

    As more and more complete bacterial genome sequences become available, the genome annotation of previously sequenced genomes may become quickly outdated. This is primarily due to the discovery and functional characterization of new genes. We have reannotated the recently published genome of Shewanella oneidensis with the following results: 51 new genes have been identified, and functional annotation has been added to the 97 genes, including 15 new and 82 existing ones with previously unassigned function. The identification of new genes was achieved by predicting the protein coding regions using the HMM-based program GeneMark.hmm. Subsequent comparison of the predicted gene products to the non-redundant protein database using BLAST and the COG (Clusters of Orthologous Groups) database using COGNITOR provided for the functional annotation. PMID:14506846

  2. Do Echinoderm Genomes Measure Up?

    PubMed Central

    Cameron, R. Andrew; Kudtarkar, Parul; Gordon, Susan M.; Worley, Kim C.; Gibbs, Richard A.

    2015-01-01

    Echinoderm genome sequences are a corpus of useful information about a clade of animals that serve as research models in fields ranging from marine ecology to cell and developmental biology. Genomic information from echinoids has contributed to insights into the gene interactions that drive the developmental process at the molecular level. Such insights often rely heavily on genomic information and the kinds of questions that can be asked thus depend on the quality of the sequence information. Here we describe the history of echinoderm genomic sequence assembly and present details about the quality of the data obtained. All of the sequence information discussed here is posted on the echinoderm information web system, Echinobase.org. PMID:25701080

  3. Genomics and equal opportunity ethics.

    PubMed

    Cappelen, A W; Norheim, O F; Tungodden, B

    2008-05-01

    Genomics provides information on genetic susceptibility to diseases and new possibilities for interventions which can fundamentally alter the design of fair health policies. The aim of this paper is to explore implications of genomics from the perspective of equal opportunity ethics. The ideal of equal opportunity requires that individuals are held responsible for some, but not all, factors that affect their health. Informational problems, however, often make it difficult to implement the ideal of equal opportunity in the context of healthcare. In this paper, examples are considered of how new genetic information may affect the way individual responsibility for choice is assigned. It is also argued that genomics may result in relocation of the responsibility cut by providing both new information and new technology. Finally, how genomics may affect healthcare policies and the market for health insurance is discussed. PMID:18448717

  4. Genomic Resources for Cancer Epidemiology

    Cancer.gov

    This page provides links to research resources, complied by the Epidemiology and Genomics Research Program, that may be of interest to genetic epidemiologists conducting cancer research, but is not exhaustive.

  5. Collaborators | Office of Cancer Genomics

    Cancer.gov

    The TARGET initiative is jointly managed within the National Cancer Institute (NCI) by the Office of Cancer Genomics (OCG)Opens in a New Tab and the Cancer Therapy Evaluation Program (CTEP)Opens in a New Tab.

  6. Genomic Datasets for Cancer Research

    Cancer.gov

    A variety of datasets from genome-wide association studies of cancer and other genotype-phenotype studies, including sequencing and molecular diagnostic assays, are available to approved investigators through the Extramural National Cancer Institute Data Access Committee.

  7. Genome Statute and Legislation Database

    MedlinePlus

    ... of page Last Reviewed: February 29, 2016 Get Email Updates Advancing human health through genomics research Privacy Copyright Contact Accessibility Plug-ins Site Map Staff Directory FOIA Share Top

  8. Genomic understanding of glioblastoma expanded

    Cancer.gov

    Glioblastoma multiforme (GBM) was the first cancer type to be systematically studied by TCGA in 2008. In a new, complementary report, TCGA experts examined more than 590 GBM samples--the largest to date utilizing genomic characterization techniques and ne

  9. Mutational dynamics of aroid chloroplast genomes.

    PubMed

    Ahmed, Ibrar; Biggs, Patrick J; Matthews, Peter J; Collins, Lesley J; Hendy, Michael D; Lockhart, Peter J

    2012-01-01

    A characteristic feature of eukaryote and prokaryote genomes is the co-occurrence of nucleotide substitution and insertion/deletion (indel) mutations. Although similar observations have also been made for chloroplast DNA, genome-wide associations have not been reported. We determined the chloroplast genome sequences for two morphotypes of taro (Colocasia esculenta; family Araceae) and compared these with four publicly available aroid chloroplast genomes. Here, we report the extent of genome-wide association between direct and inverted repeats, indels, and substitutions in these aroid chloroplast genomes. We suggest that alternative but not mutually exclusive hypotheses explain the mutational dynamics of chloroplast genome evolution. PMID:23204304

  10. Genomic imprinting and cancer.

    PubMed Central

    Joyce, J A; Schofield, P N

    1998-01-01

    Genomic imprinting is the phenomenon by which individual alleles of certain genes are expressed differentially according to their parent of origin. The alleles appear to be differentially marked during gametogenesis or during the early part of development. This mark is heritable but reversible from generation to generation, implying a stable epigenetic modification. Approximately 25 imprinted genes have been identified to date, and dysregulation of a number of these has been implicated in tumour development. The normal physiological role of many imprinted genes is in the control of cell proliferation and fetal growth, indicating potential mechanisms of action in tumour formation. Both dominant and recessive modes of action have been postulated for the role of imprinted genes in neoplasia, as a result of effective gene dosage alterations by epigenetic modification of the normal pattern of allele specific transcription. The aim of this review is to assess the importance of imprinted genes in generating tumours and to discuss the implications for novel mechanisms of transforming mutation. PMID:9893743

  11. The soft genome

    PubMed Central

    Anava, Sarit; Posner, Rachel; Rechavi, Oded

    2014-01-01

    Caenorhabditis elegans (C. elegans) nematodes transmit small RNAs across generations, a process that enables transgenerational regulation of genes. In contrast to changes to the DNA sequence, transgenerational transmission of small RNA-mediated responses is reversible, and thus enables “soft” or “flexible” inheritance of acquired characteristics. Until very recently only introduction of foreign genetic material (viruses, transposons, transgenes) was shown to directly lead to inheritance of small RNAs. New discoveries however, demonstrate that starvation also triggers inheritance of endogenous small RNAs in C.elegans. Multiple generations of worms inherit starvation-responsive endogenous small RNAs, and starvation also results in heritable extension of the progeny's lifespan. In this Commentary paper we explore the intriguing possibility that large parts of the genome and many additional traits are similarly subjected to heritable small RNA-mediated regulation, and focus on the potential influence of transgenerational RNAi on the worm's physiology. While the universal relevance of this mechanism remains to be discovered, we will examine how the discoveries made in worms already challenge long held dogmas in genetics and evolution. PMID:26430554

  12. Eukaryotic Genomics Data from the DOE Joint Genome Institute (JGI)

    DOE Data Explorer

    The JGI makes high-quality genome sequencing data freely available to the greater scientific community through its web portal. Having played a significant role in the federally funded Human Genome Project -- generating the complete sequences of Chromosomes 5, 16, and 19--the JGI has now moved on to contributing in other critical areas of genomics research. While NIH-funded genome sequencing activities continue to emphasize human biomedical targets and applications, the JGI has since shifted its focus to the non-human components of the biosphere, particularly those relevant to the science mission of the Department of Energy. With efficiencies of scale established at the PGF, and capacity now exceeding three billion bases generated on a monthly basis, the JGI has tackled scores of additional genomes. These include more than 60 microbial genomes and many important multicellular organisms and communities of microbes. In partnership with other federal institutions and universities, the JGI is in the process of sequencing a frog (Xenopus tropicalis), a green alga (Chlamydomonas reinhardtii), a diatom (Thalassiosira pseudonana) , the cottonwood tree (Populus trichocarpa), and a host of agriculturally important plants and plant pathogens. Microorganisms, for example those that thrive under extreme conditions such as high acidity, radiation, and metal contamination, are of particular interest to the DOE and JGI. Investigations by JGI and its partners are shedding light on the cellular machinery of microbes and how they can be harnessed to clean up contaminated soil or water, capture carbon from the atmosphere, and produce potentially important sources of energy such as hydrogen and methane. [Excerpt from the JGI page "Who We Are" at http://www.jgi.doe.gov/whoweare/whoweare.html] From the JGI webportal users can choose Eukaryotic genomes from a photo list, access the JGI FTP directories to download data files, use the Tree of Life navigation tool, or choose a genome and go

  13. Genomic Landscapes of Pancreatic Neoplasia

    PubMed Central

    Wood, Laura D.; Hruban, Ralph H.

    2015-01-01

    Pancreatic cancer is a deadly disease with a dismal prognosis. However, recent advances in sequencing and bioinformatic technology have led to the systematic characterization of the genomes of all major tumor types in the pancreas. This characterization has revealed the unique genomic landscape of each tumor type. This knowledge will pave the way for improved diagnostic and therapeutic approaches to pancreatic tumors that take advantage of the genetic alterations in these neoplasms. PMID:25812653

  14. IS4 family goes genomic

    PubMed Central

    2008-01-01

    Background Insertion sequences (ISs) are small, mobile DNA entities able to expand in prokaryotic genomes and trigger important rearrangements. To understand their role in evolution, accurate IS taxonomy is essential. The IS4 family is composed of ~70 elements and, like some other families, displays extremely elevated levels of internal divergence impeding its classification. The increasing availability of complete genome sequences provides a valuable source for the discovery of additional IS4 elements. In this study, this genomic database was used to update the structural and functional definition of the IS4 family. Results A total of 227 IS4-related sequences were collected among more than 500 sequenced bacterial and archaeal genomes, representing more than a three fold increase of the initial inventory. A clear division into seven coherent subgroups was discovered as well as three emerging families, which displayed distinct structural and functional properties. The IS4 family was sporadically present in 17 % of analyzed genomes, with most of them displaying single or a small number of IS4 elements. Significant expansions were detected only in some pathogens as well as among certain extremophiles, suggesting the probable involvement of some elements in bacterial and archaeal adaptation and/or evolution. Finally, it should be noted that some IS4 subgroups and two emerging families occurred preferentially in specific phyla or exclusively inside a specific genus. Conclusion The present taxonomic update of IS4 and emerging families will facilitate the classification of future elements as they arise from ongoing genome sequencing. Their narrow genomic impact and the existence of both IS-poor and IS-rich thriving prokaryotes suggested that these families, and probably ISs in general, are occasionally used as a tool for genome flexibility and evolution, rather than just representing self sustaining DNA entities. PMID:18215304

  15. Contact | Office of Cancer Genomics

    Cancer.gov

    For more information about the Office of Cancer Genomics, please contact: Office of Cancer Genomics National Cancer Institute 31 Center Drive, 10A07 Bethesda, Maryland 20892-2580 Phone: (301) 451-8027 Fax: (301) 480-4368 Email: ocg@mail.nih.gov *Please note that this site will not function properly in Internet Explorer unless you completely turn off the Compatibility View*

  16. Genome diversity of Shigella boydii.

    PubMed

    Kania, Dane A; Hazen, Tracy H; Hossain, Anowar; Nataro, James P; Rasko, David A

    2016-06-01

    ITALIC! Shigella boydiiis one of the four ITALIC! Shigellaspecies that causes disease worldwide; however, there are few published studies that examine the genomic variation of this species. This study compares genomes of 72 total isolates; 28 ITALIC! S. boydiifrom Bangladesh and The Gambia that were recently isolated as part of the Global Enteric Multicenter Study (GEMS), 14 historical ITALIC! S. boydiigenomes in the public domain and 30 ITALIC! Escherichia coliand ITALIC! Shigellareference genomes that represent the genomic diversity of these pathogens. This comparative analysis of these 72 genomes identified that the ITALIC! S. boydiiisolates separate into three phylogenomic clades, each with specific gene content. Each of the clades contains ITALIC! S. boydiiisolates from geographic and temporally distant sources, indicating that the ITALIC! S. boydiiisolates from the GEMS are representative of ITALIC! S. boydii.This study describes the genome sequences of a collection of novel ITALIC! S. boydiiisolates and provides insight into the diversity of this species in comparison to the ITALIC! E. coliand other ITALIC! Shigellaspecies. PMID:27056949

  17. Shannon Information in Complete Genomes

    NASA Astrophysics Data System (ADS)

    Hsieh, Li-Ching; Chang, Chang-Heng; Lee, Hoong-Chien

    2004-03-01

    Genomes are books of life and necessarily carry a huge amount of information. This study was first motivated by the question: "How much information do complete genomes have?" As an answer we measured a particular type of Shannon information in all prokaryotes and eukaryotes whose complete genomes have been sequenced and are available in publically assessible database. The Shannon information in complete genome sequences follow an extremely simple pattern. With the exception of one eukaryote the Shannon information in all (more than 200) complete sequences belong to a single universality class given by a simple geometric recursion formula. The data are interpreted in terms of models for genome growth and inferred to suggest that the ancestors of present day genomes began to grow, mainly by stochastic, selectively neutral, duplications and short mutations, most likely when they were not more than 300 nt long. This notion of selective neutralism independently corroborates Kimura's neutral theory of evolution which was based on the investigation of polymorphisms of genes.

  18. Genomic expression during human myelopoiesis

    PubMed Central

    Ferrari, Francesco; Bortoluzzi, Stefania; Coppe, Alessandro; Basso, Dario; Bicciato, Silvio; Zini, Roberta; Gemelli, Claudia; Danieli, Gian Antonio; Ferrari, Sergio

    2007-01-01

    Background Human myelopoiesis is an exciting biological model for cellular differentiation since it represents a plastic process where multipotent stem cells gradually limit their differentiation potential, generating different precursor cells which finally evolve into distinct terminally differentiated cells. This study aimed at investigating the genomic expression during myeloid differentiation through a computational approach that integrates gene expression profiles with functional information and genome organization. Results Gene expression data from 24 experiments for 8 different cell types of the human myelopoietic lineage were used to generate an integrated myelopoiesis dataset of 9,425 genes, each reliably associated to a unique genomic position and chromosomal coordinate. Lists of genes constitutively expressed or silent during myelopoiesis and of genes differentially expressed in commitment phase of myelopoiesis were first identified using a classical data analysis procedure. Then, the genomic distribution of myelopoiesis genes was investigated integrating transcriptional and functional characteristics of genes. This approach allowed identifying specific chromosomal regions significantly highly or weakly expressed, and clusters of differentially expressed genes and of transcripts related to specific functional modules. Conclusion The analysis of genomic expression during human myelopoiesis using an integrative computational approach allowed discovering important relationships between genomic position, biological function and expression patterns and highlighting chromatin domains, including genes with coordinated expression and lineage-specific functions. PMID:17683550

  19. Genomic sequencing in clinical trials

    PubMed Central

    2011-01-01

    Human genome sequencing is the process by which the exact order of nucleic acid base pairs in the 24 human chromosomes is determined. Since the completion of the Human Genome Project in 2003, genomic sequencing is rapidly becoming a major part of our translational research efforts to understand and improve human health and disease. This article reviews the current and future directions of clinical research with respect to genomic sequencing, a technology that is just beginning to find its way into clinical trials both nationally and worldwide. We highlight the currently available types of genomic sequencing platforms, outline the advantages and disadvantages of each, and compare first- and next-generation techniques with respect to capabilities, quality, and cost. We describe the current geographical distributions and types of disease conditions in which these technologies are used, and how next-generation sequencing is strategically being incorporated into new and existing studies. Lastly, recent major breakthroughs and the ongoing challenges of using genomic sequencing in clinical research are discussed. PMID:22206293

  20. The dynamic genome of Hydra

    PubMed Central

    Chapman, Jarrod A.; Kirkness, Ewen F.; Simakov, Oleg; Hampson, Steven E.; Mitros, Therese; Weinmaier, Therese; Rattei, Thomas; Balasubramanian, Prakash G.; Borman, Jon; Busam, Dana; Disbennett, Kathryn; Pfannkoch, Cynthia; Sumin, Nadezhda; Sutton, Granger G.; Viswanathan, Lakshmi Devi; Walenz, Brian; Goodstein, David M.; Hellsten, Uffe; Kawashima, Takeshi; Prochnik, Simon E.; Putnam, Nicholas H.; Shu, Shengquiang; Blumberg, Bruce; Dana, Catherine E.; Gee, Lydia; Kibler, Dennis F.; Law, Lee; Lindgens, Dirk; Martinez, Daniel E.; Peng, Jisong; Wigge, Philip A.; Bertulat, Bianca; Guder, Corina; Nakamura, Yukio; Ozbek, Suat; Watanabe, Hiroshi; Khalturin, Konstantin; Hemmrich, Georg; Franke, André; Augustin, René; Fraune, Sebastian; Hayakawa, Eisuke; Hayakawa, Shiho; Hirose, Mamiko; Hwang, Jung Shan; Ikeo, Kazuho; Nishimiya-Fujisawa, Chiemi; Ogura, Atshushi; Takahashi, Toshio; Steinmetz, Patrick R. H.; Zhang, Xiaoming; Aufschnaiter, Roland; Eder, Marie-Kristin; Gorny, Anne-Kathrin; Salvenmoser, Willi; Heimberg, Alysha M.; Wheeler, Benjamin M.; Peterson, Kevin J.; Böttger, Angelika; Tischler, Patrick; Wolf, Alexander; Gojobori, Takashi; Remington, Karin A.; Strausberg, Robert L.; Venter, J. Craig; Technau, Ulrich; Hobmayer, Bert; Bosch, Thomas C. G.; Holstein, Thomas W.; Fujisawa, Toshitaka; Bode, Hans R.; David, Charles N.; Rokhsar, Daniel S.; Steele, Robert E.

    2015-01-01

    The freshwater cnidarian Hydra was first described in 17021 and has been the object of study for 300 years. Experimental studies of Hydra between 1736 and 1744 culminated in the discovery of asexual reproduction of an animal by budding, the first description of regeneration in an animal, and successful transplantation of tissue between animals2. Today, Hydra is an important model for studies of axial patterning3, stem cell biology4 and regeneration5. Here we report the genome of Hydra magnipapillata and compare it to the genomes of the anthozoan Nematostella vectensis6 and other animals. The Hydra genome has been shaped by bursts of transposable element expansion, horizontal gene transfer, trans-splicing, and simplification of gene structure and gene content that parallel simplification of the Hydra life cycle. We also report the sequence of the genome of a novel bacterium stably associated with H. magnipapillata. Comparisons of the Hydra genome to the genomes of other animals shed light on the evolution of epithelia, contractile tissues, developmentally regulated transcription factors, the Spemann–Mangold organizer, pluripotency genes and the neuromuscular junction. PMID:20228792

  1. Comparative genomic analyses in Asparagus.

    PubMed

    Kuhl, Joseph C; Havey, Michael J; Martin, William J; Cheung, Foo; Yuan, Qiaoping; Landherr, Lena; Hu, Yi; Leebens-Mack, James; Town, Christopher D; Sink, Kenneth C

    2005-12-01

    Garden asparagus (Asparagus officinalis L.) belongs to the monocot family Asparagaceae in the order Asparagales. Onion (Allium cepa L.) and Asparagus officinalis are 2 of the most economically important plants of the core Asparagales, a well supported monophyletic group within the Asparagales. Coding regions in onion have lower GC contents than the grasses. We compared the GC content of 3374 unique expressed sequence tags (ESTs) from A. officinalis with Lycoris longituba and onion (both members of the core Asparagales), Acorus americanus (sister to all other monocots), the grasses, and Arabidopsis. Although ESTs in A. officinalis and Acorus had a higher average GC content than Arabidopsis, Lycoris, and onion, all were clearly lower than the grasses. The Asparagaceae have the smallest nuclear genomes among all plants in the core Asparagales, which typically have huge genomes. Within the Asparagaceae, European Asparagus species have approximately twice the nuclear DNA of that of southern African Asparagus species. We cloned and sequenced 20 genomic amplicons from European A. officinalis and the southern African species Asparagus plumosus and observed no clear evidence for a recent genome doubling in A. officinalis relative to A. plumosus. These results indicate that members of the genus Asparagus with smaller genomes may be useful genomic models for plants in the core Asparagales. PMID:16391674

  2. Genomics and marine microbial ecology.

    PubMed

    Pedrós-Alió, Carlos

    2006-09-01

    Genomics has brought about a revolution in all fields of biology. Before the development of microbial ecology in the 1970s, microbes were not even considered in marine ecological studies. Today we know that half of the total primary production of the planet must be credited to microorganisms. This and other discoveries have changed dramatically the perspective and the focus of marine microbial ecology. The application of genomics-based approaches has provided new challenges and has allowed the discovery of novel functions, an appreciation of the great diversity of microorganisms, and the introduction of controversial ideas regarding the concepts of species, genome, and niche. Nevertheless, thorough knowledge of the traditional disciplines of biology is necessary to explore the possibilities arising from these new insights. This work reviews the different genomic techniques that can be applied to marine microbial ecology, including both sequencing of the complete genomes of microorganisms and metagenomics, which, in turn, can be complemented with the study of mRNAs (transcriptomics) and proteins (proteomics). The example of proteorhodopsin illustrates the type of information that can be gained from these approaches. A genomics perspective constitutes a map that will allow microbiologists to focus their research on potentially more productive aspects. PMID:17061209

  3. Comparative genomic hybridization with single cells after whole genome amplification

    SciTech Connect

    Haddad, B.R.; Baldini, A.; Hughes, M.R.

    1994-09-01

    Conventional karyotype analysis is the ideal way to diagnose chromosomal imbalances. However it requires cell culture and chromosome preparation. There are instances where a very small number of cells are available for cytogenetic evaluation and chromosomes cannot be obtained. Comparative genomic hybridization (CGH) is a novel molecular cytogenetic technique that provides information about genetic imbalances affecting the genome. The power of this technique lies in its ability to detect genetic imbalances using total genomic DNA. We have previously demonstrated the feasibility of whole genome amplification from single cells for subsequent analysis of multiple genetic loci by PCR. In this present work, we combine whole genome amplification with CGH to detect chromosomal imbalances from small numbers of cells. Both cytogenetically normal and abnormal cells were individually picked by micromanipulation and subjected to whole genome amplification using random oligonucleotide primers. Amplified test and control DNA were differentially labeled by incorporation of digoxigenin or biotin, mixed together and hybridized to normal male metaphase spreads. Hybridization was detected with two fluorochromes, rhodamine-anti-digoxigenin and FITC -Avidin. Ratio of intensities of the two fluorochromes along the target chromosomes was analyzed using locally developed computer imaging software. Using the combination of whole genome amplification and CGH, we were able to detect different chromosomal aneuploidies from 30, 20, and 10 cells. It can also be applied to the analysis of fetal cells sorted from maternal circulation, or to tumor cells obtained from needle biopsies or from different body fluids and effusions. Finally, its successful application to single cells will have a great impact on preimplantation diagnosis.

  4. Genomics and museum specimens.

    PubMed

    Nachman, Michael W

    2013-12-01

    Nearly 25 years ago, Allan Wilson and colleagues isolated DNA sequences from museum specimens of kangaroo rats (Dipodomys panamintinus) and compared these sequences with those from freshly collected animals (Thomas et al. 1990). The museum specimens had been collected up to 78 years earlier, so the two samples provided a direct temporal comparison of patterns of genetic variation. This was not the first time DNA sequences had been isolated from preserved material, but it was the first time it had been carried out with a population sample. Population geneticists often try to make inferences about the influence of historical processes such as selection, drift, mutation and migration on patterns of genetic variation in the present. The work of Wilson and colleagues was important in part because it suggested a way in which population geneticists could actually study genetic change in natural populations through time, much the same way that experimentalists can do with artificial populations in the laboratory. Indeed, the work of Thomas et al. (1990) spawned dozens of studies in which museum specimens were used to compare historical and present-day genetic diversity (reviewed in Wandeler et al. 2007). All of these studies, however, were limited by the same fundamental problem: old DNA is degraded into short fragments. As a consequence, these studies mostly involved PCR amplification of short templates, usually short stretches of mitochondrial DNA or microsatellites. In this issue, Bi et al. (2013) report a breakthrough that should open the door to studies of genomic variation in museum specimens. They used target enrichment (exon capture) and next-generation (Illumina) sequencing to compare patterns of genetic variation in historic and present-day population samples of alpine chipmunks (Tamias alpinus) (Fig. 1). The historic samples came from specimens collected in 1915, so the temporal span of this comparison is nearly 100 years. PMID:24138088

  5. Brazil: public health genomics.

    PubMed

    Castilla, E E; Luquetti, D V

    2009-01-01

    Brazil represents half of South America and one third of Latin America, having more than 186 million inhabitants. After China and India it is the third largest developing country in the world. The wealth is unequally distributed among the states and among the people. Brazil has a large and complex health care system. A Universal Public Health System (SUS: Sistema SPACEnico de Saúde) covers the medical expenses for 80% of the population. The genetic structure of the population is very complex, including a large proportion of tri- hybrid persons, genetic isolates, and a panmictic large majority. Genetic services are offered at 64 genetic centers, half of them public and free. Nationwide networks are operating for inborn errors of metabolism, oncogenetics, and craniofacial anomalies. The Brazilian Society of Medical Genetics (SBGM) has granted 120 board certifications since 1986, and 7 recognized residences in medical genetics are operating in the country. Three main public health actions promoted by the federal government have been undertaken in the last decade, ultimately aimed at the prevention of birth defects. Since 1999, birth defects are reported for all 3 million annual live births, several vaccination strategies aim at the eradication of rubella, and wheat and maize flours are fortified with folic acid. Currently, the government distributes over 2 million US dollars to finance 14 research projects aimed at providing the basis for the adequate prevention and care of genetics disorders through the SUS. Continuity of this proactive attitude of the government in the area of genomics in public health is desired. PMID:19023184

  6. The mouse genome informatics and the mouse genome database

    SciTech Connect

    Maltais, L.J.; Blackburn, R.E.; Bradt, D.W.

    1994-09-01

    The Mouse Genome Database (MGD) is a centralized, comprehensive database of the mouse genome that includes genetic mapping data, comparative mapping data, gene descriptions, mutant phenotype descriptions, strains and allelic polymorphism data, inbred strain characteristics, physical mapping data, and molecular probes and clones data. Data in MGD are obtained from the published literature and by electronic transfer from laboratories working on large backcross panels of mice. MGD provides tools that enable the user to search the database, retrieve data, generate reports, analyze data, annotate records, and build genetic maps. The Encyclopedia of the Mouse Genome provides a graphic user interface to mouse genome data. It consists of software tools including: LinkMap, a graphic display of genetic linkage maps with the ability to magnify regions of high locus density: CytoMap, a graphic display of cytogenetic maps showing banded chromosomes with cytogenetic locations of genes and chromosomal aberrations; CATS, a catalog searching tool for text retrieval of mouse locus descriptions. These software tools provide access to the following data sets: Chromosome Committee Reports, MIT Genome Center data, GBASE reports, Mouse Locus Catalog (MLC), and Mouse Cytogenetic Mapping Data. The MGD is available to the scientific community through the World Wide Web (WWW) and Gopher. In addition GBASE can be accessed via the Internet.

  7. Genomic repeats, genome plasticity and the dynamics of Mycoplasma evolution

    PubMed Central

    Rocha, Eduardo P. C.; Blanchard, Alain

    2002-01-01

    Mycoplasmas evolved by a drastic reduction in genome size, but their genomes contain numerous repeated sequences with important roles in their evolution. We have established a bioinformatic strategy to detect the major recombination hot-spots in the genomes of Mycoplasma pneumoniae, Mycoplasma genitalium, Ureaplasma urealyticum and Mycoplasma pulmonis. This allowed the identification of large numbers of potentially variable regions, as well as a comparison of the relative recombination potentials of different genomic regions. Different trends are perceptible among mycoplasmas, probably due to different functional and structural constraints. The largest potential for illegitimate recombination in M.pulmonis is found at the vsa locus and its comparison in two different strains reveals numerous changes since divergence. On the other hand, the main M.pneumoniae and M.genitalium adhesins rely on large distant repeats and, hence, homologous recombination for variation. However, the relation between the existence of repeats and antigenic variation is not necessarily straightforward, since repeats of P1 adhesin were found to be anti-correlated with epitopes recognized by patient antibodies. These different strategies have important consequences for the structures of genomes, since large distant repeats correlate well with the major chromosomal rearrangements. Probably to avoid such events, mycoplasmas strongly avoid inverse repeats, in comparison to co-oriented repeats. PMID:11972343

  8. Mapping whole genome shotgun sequence and variant calling in mammalian species without their reference genomes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genomics research in mammals has produced reference genome sequences that are essential for identifying variation associated with disease. High quality reference genome sequences are now available for humans, model species, and economically important agricultural animals. Comparisons between these s...

  9. GOLD: The Genomes Online Database

    DOE Data Explorer

    Kyrpides, Nikos; Liolios, Dinos; Chen, Amy; Tavernarakis, Nektarios; Hugenholtz, Philip; Markowitz, Victor; Bernal, Alex

    Since its inception in 1997, GOLD has continuously monitored genome sequencing projects worldwide and has provided the community with a unique centralized resource that integrates diverse information related to Archaea, Bacteria, Eukaryotic and more recently Metagenomic sequencing projects. As of September 2007, GOLD recorded 639 completed genome projects. These projects have their complete sequence deposited into the public archival sequence databases such as GenBank EMBL,and DDBJ. From the total of 639 complete and published genome projects as of 9/2007, 527 were bacterial, 47 were archaeal and 65 were eukaryotic. In addition to the complete projects, there were 2158 ongoing sequencing projects. 1328 of those were bacterial, 59 archaeal and 771 eukaryotic projects. Two types of metadata are provided by GOLD: (i) project metadata and (ii) organism/environment metadata. GOLD CARD pages for every project are available from the link of every GOLD_STAMP ID. The information in every one of these pages is organized into three tables: (a) Organism information, (b) Genome project information and (c) External links. [The Genomes On Line Database (GOLD) in 2007: Status of genomic and metagenomic projects and their associated metadata, Konstantinos Liolios, Konstantinos Mavromatis, Nektarios Tavernarakis and Nikos C. Kyrpides, Nucleic Acids Research Advance Access published online on November 2, 2007, Nucleic Acids Research, doi:10.1093/nar/gkm884]

    The basic tables in the GOLD database that can be browsed or searched include the following information:

    • Gold Stamp ID
    • Organism name
    • Domain
    • Links to information sources
    • Size and link to a map, when available
    • Chromosome number, Plas number, and GC content
    • A link for downloading the actual genome data
    • Institution that did the sequencing
    • Funding source
    • Database where information resides
    • Publication status and information

    • GIPSy: Genomic island prediction software.

      PubMed

      Soares, Siomar C; Geyik, Hakan; Ramos, Rommel T J; de Sá, Pablo H C G; Barbosa, Eudes G V; Baumbach, Jan; Figueiredo, Henrique C P; Miyoshi, Anderson; Tauch, Andreas; Silva, Artur; Azevedo, Vasco

      2016-08-20

      Bacteria are highly diverse organisms that are able to adapt to a broad range of environments and hosts due to their high genomic plasticity. Horizontal gene transfer plays a pivotal role in this genome plasticity and in evolution by leaps through the incorporation of large blocks of genome sequences, ordinarily known as genomic islands (GEIs). GEIs may harbor genes encoding virulence, metabolism, antibiotic resistance and symbiosis-related functions, namely pathogenicity islands (PAIs), metabolic islands (MIs), resistance islands (RIs) and symbiotic islands (SIs). Although many software for the prediction of GEIs exist, they only focus on PAI prediction and present other limitations, such as complicated installation and inconvenient user interfaces. Here, we present GIPSy, the genomic island prediction software, a standalone and user-friendly software for the prediction of GEIs, built on our previously developed pathogenicity island prediction software (PIPS). We also present four application cases in which we crosslink data from literature to PAIs, MIs, RIs and SIs predicted by GIPSy. Briefly, GIPSy correctly predicted the following previously described GEIs: 13 PAIs larger than 30kb in Escherichia coli CFT073; 1 MI for Burkholderia pseudomallei K96243, which seems to be a miscellaneous island; 1 RI of Acinetobacter baumannii AYE, named AbaR1; and, 1 SI of Mesorhizobium loti MAFF303099 presenting a mosaic structure. GIPSy is the first life-style-specific genomic island prediction software to perform analyses of PAIs, MIs, RIs and SIs, opening a door for a better understanding of bacterial genome plasticity and the adaptation to new traits. PMID:26376473

    • Genome size: a novel genomic signature in support of Afrotheria.

      PubMed

      Redi, Carlo Alberto; Garagna, Silvia; Zuccotti, Maurizio; Capanna, Ernesto

      2007-04-01

      Molecular phylogenetic analyses suggest an emerging phylogeny for the extant Placentalia (eutherian) that radically departs from morphologically based constructions of the past. Placental mammals are partitioned into four supraordinal clades: Afrotheria, Xenarthra, Laurasiatheria, and Euarchontoglires. Afrotheria form an endemic African clade that includes elephant shrews, golden moles, tenrecs, aardvarks, hyraxes, elephants, dugongs, and manatees. Datamining databases of genome size (GS) shows that till today just one afrotherian GS has been evaluated, that of the aardvark Orycteropus afer. We show that the GSs of six selected representatives across the Afrotheria supraordinal group are among the highest for the extant Placentalia, providing a novel genomic signature of this enigmatic group. The mean GS value of Afrotheria, 5.3 +/- 0.7 pg, is the highest reported for the extant Placentalia. This should assist in planning new genome sequencing initiatives. PMID:17479346

    • Genomics made easier: an introductory tutorial to genome datamining.

      PubMed

      Schattner, Peter

      2009-03-01

      Integrated genome databases--such as the UCSC, Ensembl and NCBI MapViewer databases--and their associated data querying and visualization interfaces (e.g. the genome browsers) have transformed the way that molecular biologists, geneticists and bioinformaticists analyze genomic data. Nevertheless, because of the complexity of these tools, many researchers take advantage of only a fraction of their capabilities. In this tutorial, using examples from medical genetics and alternative splicing, I describe some of the biological questions that can be addressed with these techniques. I also show why doing so typically is more effective than using alternative methods and indicate some of the resources available for learning more about the advanced capabilities of these powerful tools. PMID:19041391

    • Linking genome-scale metabolic modeling and genome annotation

      PubMed Central

      Blais, Edik M.; Chavali, Arvind K.; Papin, Jason A.

      2014-01-01

      Summary Genome-scale metabolic network reconstructions, assembled from annotated genomes, serve as a platform for integrating data from heterogeneous sources and generating hypotheses for further experimental validation. Implementing constraint-based modeling techniques such as Flux Balance Analysis (FBA) on network reconstructions allow for interrogating metabolism at a systems-level, which aids in identifying and rectifying gaps in knowledge. With genome sequences for various organisms from prokaryotes to eukaryotes becoming increasingly available, a significant bottleneck lies in the structural and functional annotation of these sequences. Using topologically-based and biologically-inspired metabolic network refinement, we can better characterize enzymatic functions present in an organism and link annotation of these functions to candidate transcripts, both steps that can be experimentally validated. PMID:23417799

    • Synthesis and characterization of advanced durum wheat hybrids and addition lines with thinopyrum chromosomes

      Technology Transfer Automated Retrieval System (TEKTRAN)

      Durum wheat (Triticum turgidum L., 2n = 4x = 28; AABB genomes) is a natural hybrid – an allotetraploid between two wild species, Triticum urartu Tumanian (AA genome) and Aegilops speltoides Tausch (BB genome). As shown earlier, even at the allotetraploid level, durum wheat can tolerate chromosomal ...

    • Transcriptional Regulation: a Genomic Overview

      PubMed Central

      Riechmann, José Luis

      2002-01-01

      The availability of the Arabidopsis thaliana genome sequence allows a comprehensive analysis of transcriptional regulation in plants using novel genomic approaches and methodologies. Such a genomic view of transcription first necessitates the compilation of lists of elements. Transcription factors are the most numerous of the different types of proteins involved in transcription in eukaryotes, and the Arabidopsis genome codes for more than 1,500 of them, or approximately 6% of its total number of genes. A genome-wide comparison of transcription factors across the three eukaryotic kingdoms reveals the evolutionary generation of diversity in the components of the regulatory machinery of transcription. However, as illustrated by Arabidopsis, transcription in plants follows similar basic principles and logic to those in animals and fungi. A global view and understanding of transcription at a cellular and organismal level requires the characterization of the Arabidopsis transcriptome and promoterome, as well as of the interactome, the localizome, and the phenome of the proteins involved in transcription. PMID:22303220

    • Expanding genomics of mycorrhizal symbiosis

      PubMed Central

      Kuo, Alan; Kohler, Annegret; Martin, Francis M.; Grigoriev, Igor V.

      2014-01-01

      The mycorrhizal symbiosis between soil fungi and plant roots is a ubiquitous mutualism that plays key roles in plant nutrition, soil health, and carbon cycling. The symbiosis evolved repeatedly and independently as multiple morphotypes [e.g., arbuscular mycorrhizae (AM), ectomycorrhizal (ECM)] in multiple fungal clades (e.g., phyla Glomeromycota, Ascomycota, Basidiomycota). The accessibility and cultivability of many mycorrhizal partners make them ideal models for symbiosis studies. Alongside molecular, physiological, and ecological investigations, sequencing led to the first three mycorrhizal fungal genomes, representing two morphotypes and three phyla. The genome of the ECM basidiomycete Laccaria bicolor showed that the mycorrhizal lifestyle can evolve through loss of plant cell wall-degrading enzymes (PCWDEs) and expansion of lineage-specific gene families such as short secreted protein (SSP) effectors. The genome of the ECM ascomycete Tuber melanosporum showed that the ECM type can evolve without expansion of families as in Laccaria, and thus a different set of symbiosis genes. The genome of the AM glomeromycete Rhizophagus irregularis showed that despite enormous phylogenetic distance and morphological difference from the other two fungi, symbiosis can involve similar solutions as symbiosis-induced SSPs and loss of PCWDEs. The three genomes provide a solid base for addressing fundamental questions about the nature and role of a vital mutualism. PMID:25408690

    • Comparative genomics for biodiversity conservation

      PubMed Central

      Grueber, Catherine E.

      2015-01-01

      Genomic approaches are gathering momentum in biology and emerging opportunities lie in the creative use of comparative molecular methods for revealing the processes that influence diversity of wildlife. However, few comparative genomic studies are performed with explicit and specific objectives to aid conservation of wild populations. Here I provide a brief overview of comparative genomic approaches that offer specific benefits to biodiversity conservation. Because conservation examples are few, I draw on research from other areas to demonstrate how comparing genomic data across taxa may be used to inform the characterisation of conservation units and studies of hybridisation, as well as studies that provide conservation outcomes from a better understanding of the drivers of divergence. A comparative approach can also provide valuable insight into the threatening processes that impact rare species, such as emerging diseases and their management in conservation. In addition to these opportunities, I note areas where additional research is warranted. Overall, comparing and contrasting the genomic composition of threatened and other species provide several useful tools for helping to preserve the molecular biodiversity of the global ecosystem. PMID:26106461

    • Manipulating duckweed through genome duplication.

      PubMed

      Vunsh, R; Heinig, U; Malitsky, S; Aharoni, A; Avidov, A; Lerner, A; Edelman, M

      2015-01-01

      Significant inter- and intraspecific genetic variation exists in duckweed, thus the potential for genome plasticity and manipulation is high. Polyploidy is recognised as a major mechanism of adaptation and speciation in plants. We produced several genome-duplicated lines of Landoltia punctata (Spirodela oligorrhiza) from both whole plants and regenerating explants using a colchicine-based cocktail. These lines stably maintained an enlarged frond and root morphology. DNA ploidy levels determined by florescence-activated cell sorting indicated genome duplication. Line A4 was analysed after 75 biomass doublings. Frond area, fresh and dry weights, rhizoid number and length were significantly increased versus wild type, while the growth rate was unchanged. This resulted in accumulation of biomass 17-20% faster in the A4 plants. We sought to determine if specific differences in gene products are found in the genome duplicated lines. Non-targeted ultra performance LC-quadrupole time of flight mass spectrometry was employed to compare some of the lines and the wild type to seek identification of up-regulated metabolites. We putatively identified differential metabolites in Line A65 as caffeoyl hexoses. The combination of directed genome duplication and metabolic profiling might offer a path for producing stable gene expression, leading to altered production of secondary metabolites. PMID:25040392

    • Expanding genomics of mycorrhizal symbiosis

      SciTech Connect

      Kuo, Alan; Kohler, Annegret; Martin, Francis M.; Grigoriev, Igor V.

      2014-11-04

      The mycorrhizal symbiosis between soil fungi and plant roots is a ubiquitous mutualism that plays key roles in plant nutrition, soil health, and carbon cycling. The symbiosis evolved repeatedly and independently as multiple morphotypes [e.g., arbuscular mycorrhizae (AM), ectomycorrhizal (ECM)] in multiple fungal clades (e.g., phyla Glomeromycota, Ascomycota, Basidiomycota). The accessibility and cultivability of many mycorrhizal partners make them ideal models for symbiosis studies. Alongside molecular, physiological, and ecological investigations, sequencing led to the first three mycorrhizal fungal genomes, representing two morphotypes and three phyla. The genome of the ECM basidiomycete Laccaria bicolor showed that the mycorrhizal lifestyle can evolve through loss of plant cell wall-degrading enzymes (PCWDEs) and expansion of lineage-specific gene families such as short secreted protein (SSP) effectors. The genome of the ECM ascomycete Tuber melanosporum showed that the ECM type can evolve without expansion of families as in Laccaria, and thus a different set of symbiosis genes. The genome of the AM glomeromycete Rhizophagus irregularis showed that despite enormous phylogenetic distance and morphological difference from the other two fungi, symbiosis can involve similar solutions as symbiosis-induced SSPs and loss of PCWDEs. The three genomes provide a solid base for addressing fundamental questions about the nature and role of a vital mutualism.

    • Expanding genomics of mycorrhizal symbiosis

      DOE PAGESBeta

      Kuo, Alan; Kohler, Annegret; Martin, Francis M.; Grigoriev, Igor V.

      2014-11-04

      The mycorrhizal symbiosis between soil fungi and plant roots is a ubiquitous mutualism that plays key roles in plant nutrition, soil health, and carbon cycling. The symbiosis evolved repeatedly and independently as multiple morphotypes [e.g., arbuscular mycorrhizae (AM), ectomycorrhizal (ECM)] in multiple fungal clades (e.g., phyla Glomeromycota, Ascomycota, Basidiomycota). The accessibility and cultivability of many mycorrhizal partners make them ideal models for symbiosis studies. Alongside molecular, physiological, and ecological investigations, sequencing led to the first three mycorrhizal fungal genomes, representing two morphotypes and three phyla. The genome of the ECM basidiomycete Laccaria bicolor showed that the mycorrhizal lifestyle can evolvemore » through loss of plant cell wall-degrading enzymes (PCWDEs) and expansion of lineage-specific gene families such as short secreted protein (SSP) effectors. The genome of the ECM ascomycete Tuber melanosporum showed that the ECM type can evolve without expansion of families as in Laccaria, and thus a different set of symbiosis genes. The genome of the AM glomeromycete Rhizophagus irregularis showed that despite enormous phylogenetic distance and morphological difference from the other two fungi, symbiosis can involve similar solutions as symbiosis-induced SSPs and loss of PCWDEs. The three genomes provide a solid base for addressing fundamental questions about the nature and role of a vital mutualism.« less