Epitranscriptomics of the Heat-Stress Response in Arabidopsis thaliana
Résumé
Like other stresses, heat shock (HS) is known to have an impact on gene expression at different layers. HS is known to induce the transcription of genes coding for numerous Heat Stress Factors (HSF) and Heat Stress Protein (HSP) while, at the translational level, HS can block translation initiation, inducing the sequestration of mRNAs into stress granules (SGs) or P-bodies (PBs). We recently discovered that plants also regulate the HS response by inducing a massive mRNA decay process, including the co-translational degradation of slowly elongating mRNAs, suggesting the existence of a direct link between stress-induced variation of translation elongation rate and co-translational degradation of mRNAs. We also observed that mRNAs encoding ribosomal proteins are preferentially stored in SGs during HS, released in an HSP101-dependent manner and translated during the recovery period to generate new ribosomes. I will present here recent data suggesting that post-translational reprogramming of m6A reader capabilities is an important regulatory switch involved in controlling the plant HS response