Genome interplay in the grain transcriptome of hexaploid bread wheat

Abstract

Allohexaploid bread wheat (Triticum aestivum L.) provides approximately 20% of calories consumed by humans. Lack of genome sequence for the three homeologous and highly similar bread wheat genomes (A, B, and D) has impeded expression analysis of the grain transcriptome. We used previously unknown genome information to analyze the cell type-specific expression of homeologous genes in the developing wheat grain and identified distinct co-expression clusters reflecting the spatiotemporal progression during endosperm development. We observed no global but cell type- and stage-dependent genome dominance, organization of the wheat genome into transcriptionally active chromosomal regions, and asymmetric expression in gene families related to baking quality. Our findings give insight into the transcriptional dynamics and genome interplay among individual grain cell types in a polyploid cereal genome.

The E3 Ligase TaSAP5 Alters Drought Stress Responses by Promoting the Degradation of DRIP Proteins

“…Total RNA was isolated from leaf tissue using the TRIzol reagent (Invitrogen) according to the manufacturer's instructions. RNAseq data were analyzed as described previously (Pfeifer et al, 2014). Significant differential expression was defined as an absolute log 2 value (fold change; Ubi:TaSAP5-#8-10/cv CB037) .…”

The draft genome of Tibetan hulless barley reveals adaptive patterns to the high stressful Tibetan Plateau

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The Dynamics of Transcript Abundance during Cellularization of Developing Barley Endosperm

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