Project description:To improve our understanding of the organization and regulation of the wheat gene space, we established the first transcription map of a wheat chromosome (3B) by hybridizing the newly developed INRA GDEC Triticum aestivum NimbleGen 12x40k unigenes microarray with BAC pools from a new version of the 3B physical map as well as with cDNA probes from five tissues at three developmental stages each. By hybridizing the BAC pools with the wheat NimbleGen 40K unigenes chip we managed to map almost 3000 unigenes on the wheat chromosome 3B BACs and to study the organization of the wheat gene space along chromosome 3B. The sequences of the unigenes helped to perform functional and evolutionary analyses of these unigenes. By hybridizing the 15 cDNA samples from five organs at three developmental stages each we established the expression profiles of more than 32000 wheat unigenes. Particularly we focused on the expression of the unigenes mapped on wheat chromosome 3B to perform coexpression analyses.
Project description:To study the expression profiles of hexaploid wheat chromosome 3B genes during the life cycle of a wheat plant and establish a transcriptome atlas for this chromosome, deep transcriptome sequencing was conducted in duplicates in 15 wheat samples corresponding to five different organs (leaf, shoot, root, spike, and grain) at three developmental stages each. Strand-non-specific and strand-specific libraries were used to produce 2.52 billion paired-end reads (232 Gb) and 615.3 single-end reads (62 Gb), respectively.
Project description:Bread wheat (Triticum aestivum) has a large, complex and hexaploid genome consisting of A, B and D homoeologous chromosome sets. Therefore each wheat gene potentially exists as a trio of A, B and D homoeoalleles, each of which may contribute differentially to wheat phenotypes. We describe a novel approach combining wheat cytogenetic resources (chromosome substitution ânullisomic-tetrasomicâ lines) with next generation deep sequencing of gene transcripts (RNA-seq), to directly and accurately identify homoeologue-specific single nucleotide variants and quantify the relative homoeoallelic contribution to gene expression. We obtained mRNA-Seq datasets from non-normalized cDNA libraries created from shoot and root tissues of the euploid bread wheat cultivar Chinese Spring, from which the nullitetra lines are derived, from complete sets of chromosome 1 and 5 nullitetras, and from extant relatives of the diploid A (Triticum urartu) and D (Aegilops tauschii) genome donors, herein referred to as A and D genome diploids
Project description:We performed ChIP-seq for the meiotic strand exchange protein DMC1, which marks an early stage in the meiotic recombination pathway, and the chromosome axis protein ASY1, which promotes interhomolog synapsis and recombination in plants, using tissue collected from immature pre-emergence spikes from wild type bread wheat cultivar Chinese Spring plants. To investigate connections between meiotic recombination and chromatin states in wheat, we also performed ChIP-seq for euchromatic (H3K4me3) and constitutive heterochromatic (H3K9me2 and H3K27me1) marks, and mapped genome-wide nucleosome occupancy via micrococcal nuclease sequencing (MNase-seq) using leaf tissue from Chinese Spring.
Project description:We performed ChIP-seq for the meiotic strand exchange protein DMC1, which marks an early stage in the meiotic recombination pathway, and the chromosome axis protein ASY1, which promotes interhomolog synapsis and recombination in plants, using tissue collected from immature pre-emergence spikes from wild type bread wheat cultivar Chinese Spring plants. To investigate connections between meiotic recombination and chromatin states in wheat, we also performed ChIP-seq for euchromatic (H3K4me3) and constitutive heterochromatic (H3K9me2 and H3K27me1) marks, and mapped genome-wide nucleosome occupancy via micrococcal nuclease sequencing (MNase-seq) using leaf tissue from Chinese Spring.
Project description:Background Because of its size, allohexaploid nature and high repeat content, the wheat genome has always been perceived as too complex for efficient molecular studies. However, we recently constructed the first physical map of a wheat chromosome (3B). But gene mapping is still laborious in wheat because of high redundancy between the three homoeologous genomes. In contrast, in the closely related diploid species, barley, numerous gene-based markers have been developed. This study aims at combining the unique genomic resources developed in wheat and barley to decipher the organisation of gene space on wheat chromosome 3B. Results Three dimensional pools of the minimal tiling path of wheat chromosome 3B physical map were hybridized to a barley Agilent 15K expression microarray. This led to the identification of 738 barley genes with a homolog on wheat chromosome 3B. In addition, comparative analyses revealed that 68% of the genes identified were syntenic between the wheat chromosome 3B and barley chromosome 3H and 59% between wheat chromosome 3B and rice chromosome 1, together with some wheat-specific rearrangements. Finally, it indicated an increasing gradient of gene density from the centromere to the telomeres positively correlated with the number of genes clustered in islands on wheat chromosome 3B. Conclusion Our study shows that novel structural genomics resources now available in wheat and barley can be combined efficiently to overcome specific problems of genetic anchoring of physical contigs in wheat and to perform high-resolution comparative analyses with rice for deciphering the organisation of the wheat gene space.