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:Bread wheat is the major staple food of the world with a complex hexaploidy genome. The precise spatiotemporal gene expression is orchestrated by enhancers, which lack general sequence features and thus are difficult to be located, especially in large genomes. Epigenomic architecture, including chromatin openness and active chromatin marks, has been widely used to characterize enhancers. However, an active chromatin environment does not necessarily mean an active enhancer. Recently, enhancer RNAs (eRNAs), the hallmark for active enhancers, have been detected by nascent RNA sequencing in both Drosophila and mammalian. In order to answer whether plant enhancers could be transcribed, we investigated the transcriptome of bread wheat via two nascent RNA sequencing methods, GRO-seq and pNET-seq combining with epigenome profiling. Our study demonstrates the presence and wide distribution of transcription at intergenic enhancers, which accurately reflects high enhancer activity, shedding light on the complex gene expression regulation across subgenomes in bread wheat.
Project description:Allohexaploid bread wheat (Triticum aestivum, L.) provides ~ 20% of calories consumed by humans. Hitherto lack of genome sequence for the three homoelogous and highly similar bread wheat genomes (A, B and, D) impeded expression analysis of the grain transcriptome. We used novel genome information to analyze the cell type specific expression of homeologous genes in the developing wheat grain.
Project description:One week old bread wheat plantlets were artifically infected with Puccinia triticinae (the causal organism of wheat leaf rust) and samples were collected after one week from infection. Samples were collected after one week from infection, non infected as well. Two loacl varities were used MISR 1 and GEMMZA 7.
Project description:Cuticular waxes coating leaf surfaces can help tolerate drought events by reducing non-stomatal water loss. Despite their role in drought tolerance, little is known about the cuticular wax responses of Canadian bread wheat varieties. To fill in this gap, RNAseq was performed on the flag leaf of four modern varieties to identify potential markers that could be used for selection of higher accumulation of cuticular waxes. This analysis revealed that the W1 locus is a good candidate for higher accumulation of β-diketones.
Project description:Iron (Fe) plays a pivotal role in several metabolic and biosynthetic pathways essential for plant growth. Fe deficiency in plants severely affects the overall crop yield. Despite several studies on iron deficiency responses in different plant species, these mechanisms remain unclear in the allohexaploid wheat, which is the most widely cultivated commercial crop. In order to gain a comprehensive insight into molecular responses of bread wheat when exposed to iron deficiency, we studied transcriptomic changes in the roots and flag leaves of wheat plants subjected to iron-deficient and iron-sufficient conditions during early grain filling.