Abstract
Methylation of internal adenosine at nitrogen-6 position (m(6)A) is the most abundant post-transcriptional modification in eukaryotic RNAs. These modifications are recognized by m(6)A-binding proteins ('readers') that affect downstream functions. In plants, the scope of gene expression regulation by reader proteins is not clear. Here, overexpression and loss-of-function mutants were used to characterize the role of the Arabidopsis m(6)A reader ECT2 in proteasome regulation. ECT2 regulates the mRNA levels of the proteasome regulator PTRE1 and of several 20S proteasome subunits, resulting in enhanced 26S proteasome activity. This regulation is dependent on ECT2 m(6)A binding function. Interestingly, though ECT2 positively regulates proteasome activity in both young and mature plants, PTRE1 has different regulatory effects in different developmental stages. In mature plants, PTRE1 inhibits 26S proteasome activity, while in seedlings PTRE1 knockout mutants have reduced 26S proteasome activity. Taken together, our results suggest a novel epitranscriptomic mechanism of proteasome regulation by ECT2 that is used to fine tune proteasome activity by affecting the expression of PTRE1 and 20S proteasome subunits.
Original language | English |
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Pages (from-to) | 151-162 |
Number of pages | 12 |
Journal | New Phytologist |
Volume | 228 |
Issue number | 1 |
Early online date | 16 May 2020 |
DOIs | |
Publication status | Published - Oct 2020 |
Funding
We thank Dr. Tamar Avin‐Wittenberg, Prof. Schraga Schwartz and Dr Yonghui Dong for critical reading of the manuscript and helpful comments, and Eden Hazansky for her excellent assistance in the scientific experiments. This work was supported by Israel Science Foundation (grant 612/16) and by an Israel’s Council for Higher Education Planning and Budgeting Committee (VATAT) postdoctoral fellowship to JW. GG is an incumbent of the Bronfman Chair of Plant Science at The Weizmann Institute of Science. JW performed the experiments. JW, HP‐Z and GG designed the experiments and wrote the manuscript. Israel Science Foundation. Grant Number: grant 612/16 Council for Higher Education Planning and Budgeting Committee
All Science Journal Classification (ASJC) codes
- Physiology
- Plant Science