Heat-induced ribosome pausing triggers mRNA co-translational decay in Arabidopsis thaliana

Nucleic Acids Res. 2015 Apr 30;43(8):4121-32. doi: 10.1093/nar/gkv234. Epub 2015 Apr 6.


The reprogramming of gene expression in heat stress is a key determinant to organism survival. Gene expression is downregulated through translation initiation inhibition and release of free mRNPs that are rapidly degraded or stored. In mammals, heat also triggers 5'-ribosome pausing preferentially on transcripts coding for HSC/HSP70 chaperone targets, but the impact of such phenomenon on mRNA fate remains unknown. Here, we provide evidence that, in Arabidopsis thaliana, heat provokes 5'-ribosome pausing leading to the XRN4-mediated 5'-directed decay of translating mRNAs. We also show that hindering HSC/HSP70 activity at 20°C recapitulates heat effects by inducing ribosome pausing and co-translational mRNA turnover. Strikingly, co-translational decay targets encode proteins with high HSC/HSP70 binding scores and hydrophobic N-termini, two characteristics that were previously observed for transcripts most prone to pausing in animals. This work suggests for the first time that stress-induced variation of translation elongation rate is an evolutionarily conserved process leading to the polysomal degradation of thousands of 'non-aberrant' mRNAs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / genetics*
  • Arabidopsis / metabolism
  • Down-Regulation
  • Exoribonucleases / metabolism
  • Gene Expression Regulation, Plant*
  • HSP70 Heat-Shock Proteins / metabolism
  • Hot Temperature*
  • Plant Proteins / metabolism
  • Polyribosomes / metabolism
  • Protein Biosynthesis*
  • RNA Stability
  • RNA, Messenger / metabolism*
  • Ribosomes / metabolism*
  • Stress, Physiological / genetics*


  • HSP70 Heat-Shock Proteins
  • Plant Proteins
  • RNA, Messenger
  • Xrn1 protein, plant
  • Exoribonucleases