1. The m6A reader ECT1 drives mRNA sequestration to dampen salicylic acid-dependent stress responses in Arabidopsis.
- Author
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Lee KP, Liu K, Kim EY, Medina-Puche L, Dong H, Di M, Singh RM, Li M, Qi S, Meng Z, Cho J, Zhang H, Lozano-Duran R, and Kim C
- Subjects
- Salicylic Acid metabolism, RNA, Messenger genetics, RNA, Messenger metabolism, Gene Expression Regulation, Plant, Arabidopsis metabolism, Arabidopsis Proteins genetics, Arabidopsis Proteins metabolism, Adenine analogs & derivatives
- Abstract
N 6-methyladenosine (m6A) is a common epitranscriptional mRNA modification in eukaryotes. Thirteen putative m6A readers, mostly annotated as EVOLUTIONARILY CONSERVED C-TERMINAL REGION (ECT) proteins, have been identified in Arabidopsis (Arabidopsis thaliana), but few have been characterized. Here, we show that the Arabidopsis m6A reader ECT1 modulates salicylic acid (SA)-mediated plant stress responses. ECT1 undergoes liquid-liquid phase separation in vitro, and its N-terminal prion-like domain is critical for forming in vivo cytosolic biomolecular condensates in response to SA or bacterial pathogens. Fluorescence-activated particle sorting coupled with quantitative PCR analyses unveiled that ECT1 sequesters SA-induced m6A modification-prone mRNAs through its conserved aromatic cage to facilitate their decay in cytosolic condensates, thereby dampening SA-mediated stress responses. Consistent with this finding, ECT1 overexpression promotes bacterial multiplication in plants. Collectively, our findings unequivocally link ECT1-associated cytosolic condensates to SA-dependent plant stress responses, advancing the current understanding of m6A readers and the SA signaling network., Competing Interests: Conflict of interest statement. None declared., (© The Author(s) 2023. Published by Oxford University Press on behalf of American Society of Plant Biologists. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
- Published
- 2024
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