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Title: m 6 A modification plays an integral role in mRNA stability and translation during pattern-triggered immunity
Plants employ distinct mechanisms to respond to environmental changes. Modification of mRNA byN 6-methyladenosine (m6A), known to affect the fate of mRNA, may be one such mechanism to reprogram mRNA processing and translatability upon stress. However, it is difficult to distinguish a direct role from a pleiotropic effect for this modification due to its prevalence in RNA. Through characterization of the transient knockdown-mutants of m6A writer components and mutants of specific m6A readers, we demonstrate the essential role that m6A plays in basal resistance and pattern-triggered immunity (PTI). A global m6A profiling of mock and PTI-inducedArabidopsisplants as well as formaldehyde fixation and cross-linking immunoprecipitation-sequencing of the m6A reader, EVOLUTIONARILY CONSERVED C-TERMINAL REGION2 (ECT2) showed that while dynamic changes in m6A modification and binding by ECT2 were detected upon PTI induction, most of the m6A sites and their association with ECT2 remained static. Interestingly, RNA degradation assay identified a dual role of m6A in stabilizing the overall transcriptome while facilitating rapid turnover of immune-induced mRNAs during PTI. Moreover, polysome profiling showed that m6A enhances immune-associated translation by binding to the ECT2/3/4 readers. We propose that m6A plays a positive role in plant immunity by destabilizing defense mRNAs while enhancing their translation efficiency to create a transient surge in the production of defense proteins.  more » « less
Award ID(s):
2041378
PAR ID:
10588163
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
National Academy of Sciences
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
121
Issue:
33
ISSN:
0027-8424
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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