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Title: Multiple chromatin‐associated modules regulate expression of an intracellular immune receptor gene in Arabidopsis
Summary

The expression of an intracellular immune receptor geneSNC1(SUPPRESSOR OF npr1,CONSTITUTIVE 1) is regulated by multiple chromatin‐associated proteins for tuning immunity and growth in Arabidopsis. Whether and how these regulators coordinate to regulateSNC1expression under varying environmental conditions is not clear.

Here, we identified two activation and one repression regulatory modules based on genetic and molecular characterizations of five chromatin‐associated regulators ofSNC1.

Modifier ofsnc1(MOS1) constitutes the first module and is required for the interdependent functions of ARABIDOPSIS TRITHORAX‐RELATED 7 (ATXR7) and HISTONE MONOUBIQUITINATION 1 (HUB1) to deposit H3K4me3 and H2Bub1 at theSNC1locus. CHROMATIN REMODELING 5 (CHR5) constitutes a second module and works independently of ATXR7 and HUB1 in the MOS1 module. HIGH EXPRESSION OF OSMOTICALLY RESPONSIVE GENES 15 (HOS15) constitutes a third module responsible for removing H3K9ac to repressSNC1expression under nonpathogenic conditions. The upregulation ofSNC1resulting from removing the HOS15 repression module is partially dependent on the function of the CHR5 module and the MOS1 module.

Together, this study reveals both the distinct and interdependent regulatory mechanisms at the chromatin level forSNC1expression regulation and highlights the intricacy of regulatory mechanisms of NLR expression under different environment.

 
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NSF-PAR ID:
10397453
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
New Phytologist
Volume:
237
Issue:
6
ISSN:
0028-646X
Page Range / eLocation ID:
p. 2284-2297
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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