Circadian regulation of the transcriptome in a complex polyploid crop.

The circadian clock is a finely balanced timekeeping mechanism that coordinates programmes of gene expression. It is currently unknown how the clock regulates expression of homoeologous genes in polyploids. Here, we generate a high-resolution time-course dataset to investigate the circadian balance between sets of 3 homoeologous genes (triads) from hexaploid bread wheat. We find a large proportion of circadian triads exhibit imbalanced rhythmic expression patterns, with no specific subgenome favoured. In wheat, period lengths of rhythmic transcripts are found to be longer and have a higher level of variance than in other plant species. Expression of transcripts associated with circadian controlled biological processes is largely conserved between wheat and ; however, striking differences are seen in agriculturally critical processes such as starch metabolism. Together, this work highlights the ongoing selection for balance versus diversification in circadian homoeologs and identifies clock-controlled pathways that might provide important targets for future wheat breeding.

Contributor (person)

Ronald, Pamela C.

Funder

Funder name	Awards
Biotechnology and Biological Sciences Research Council, United Kingdom	BB/CSP1720/1 - BBS/E/T/000PR9819 - BB/P016855/1 - BBS/E/T/000PR9783 - BB/M011216/1 - BB/V509267/1 - BBS/E/T/000PR9816 - BB/CCG1720/1 - BB/N023145/1 - BB/P013511/1 - BB/M009122/1
Engineering and Physical Sciences Research Council, United Kingdom	EP/T001569/1