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Title: DNA methyltransferase CHROMOMETHYLASE3 prevents ONSEN transposon silencing under heat stress
DNA methylation plays crucial roles in transposon silencing and genome integrity. CHROMOMETHYLASE3 (CMT3) is a plant-specific DNA methyltransferase responsible for catalyzing DNA methylation at the CHG (H = A, T, C) context. Here, we identified a positive role of CMT3 in heat-induced activation of retrotransposonONSEN. We found that the full transcription ofONSENunder heat stress requires CMT3. Interestingly, loss-of-function CMT3 mutation led to increased CHH methylation atONSEN. The CHH methylation is mediated by CMT2, as evidenced by greatly reduced CHH methylation incmt2andcmt2 cmt3mutants coupled with increasedONSENtranscription. Furthermore, we found more CMT2 binding atONSENchromatin incmt3compared to wild-type accompanied with an ectopic accumulation of H3K9me2 under heat stress, suggesting a collaborative role of H3K9me2 and CHH methylation in preventing heat-inducedONSENactivation. In summary, this study identifies a non-canonical role of CMT3 in preventing transposon silencing and provides new insights into how DNA methyltransferases regulate transcription under stress conditions.  more » « less
Award ID(s):
2043544 2228767
PAR ID:
10485382
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Editor(s):
Springer, Nathan M.
Publisher / Repository:
A nonprofit publisher of open-access journal
Date Published:
Journal Name:
PLOS Genetics
Volume:
17
Issue:
8
ISSN:
1553-7404
Page Range / eLocation ID:
e1009710
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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