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Title: F‐box protein CFK1 interacts with and degrades de novo DNA methyltransferase in Arabidopsis
Summary

DNA methylation plays crucial roles in cellular development and stress responses through gene regulation and genome stability control. Precise regulation of DOMAINS REARRANGED METHYLTRANSFERASE 2 (DRM2), thede novoArabidopsis DNA methyltransferase, is crucial to maintain DNA methylation homeostasis to ensure genome integrity. Compared with the extensive studies on DRM2 targeting mechanisms, little information is known regarding the quality control of DRM2 itself.

Here, we conducted yeast two‐hybrid screen assay and identified an E3 ligase, COP9 INTERACTING F‐BOX KELCH 1 (CFK1), as a novel DRM2‐interacting partner and targets DRM2 for degradation via the ubiquitin‐26S proteasome pathway inArabidopsis thaliana. We also performed whole genome bisulfite sequencing (BS‐seq) to determine the biological significance of CFK1‐mediated DRM2 degradation.

Loss‐of‐functionCFK1leads to increased DRM2 protein abundance and overexpression of CFK1 showed reduced DRM2 protein levels. Consistently, CFK1 overexpression induces genome‐wide CHH hypomethylation and transcriptional de‐repression at specific DRM2 target loci.

This study uncovered a distinct mechanism regulatingde novoDNA methyltransferase by CFK1 to control DNA methylation level.

 
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Award ID(s):
1750361
PAR ID:
10452798
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
New Phytologist
Volume:
229
Issue:
6
ISSN:
0028-646X
Page Range / eLocation ID:
p. 3303-3317
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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