Extensive Translational Regulation of Gene Expression in an Allopolyploid (Glycine dolichocarpa). Issue 1 (31st January 2014)

• Record Type: Journal Article
• Authors: Coate, Jeremy E.; Bar, Haim; Doyle, Jeff J.
• Is Part Of: The Plant Cell. Volume 26:Issue 1(2014)
• Page Start: 136
• Page End: 150
• Publication Date: 2014-01-31
• DOI: 10.1105/tpc.113.119966
• Languages: English
• ISSNs: 1040-4651

Abstract

Abstract : This work shows that translational regulation of gene expression in a recently formed allopolyploid is widespread, reduces transcriptional differences between the polyploid and its diploid progenitors, and correlates with the retention of genes from an older polyploidy event. These findings suggest that translational regulation is significant in both early and long-term responses to polyploidy. Abstract: All flowering plants have experienced repeated rounds of polyploidy (whole-genome duplication), which has in turn driven the evolution of novel phenotypes and ecological tolerances and been a major driver of speciation. The effects of polyploidy on gene expression have been studied extensively at the level of transcription and, to a much lesser extent, at the level of the steady state proteome, but not at the level of translation. We used polysome profiling by RNA-Seq to quantify translational regulation of gene expression in a recently formed (∼100, 000 years ago) allotetraploid ( Glycine dolichocarpa ) closely related to the cultivated soybean ( Glycine max ). We show that there is a high level of concordance between the allopolyploid transcriptome and translatome overall but that at least one-quarter of the transcriptome is translationally regulated. We further show that translational regulation preferentially targets genes involved in transcription, translation, and photosynthesis, causes regional and possibly whole-chromosome shifts in expression bias between duplicated genes (homoeologs), and reduces transcriptional differences between the polyploid and its diploid progenitors, possibly attenuating misregulation resulting from genome merger and/or doubling. Finally, translational regulation correlates positively with long-term retention of homoeologs from a paleopolyploidy event, suggesting that it plays a significant role in polyploid evolution.