The expression of an intracellular immune receptor gene Here, we identified two activation and one repression regulatory modules based on genetic and molecular characterizations of five chromatin‐associated regulators of Modifier of Together, this study reveals both the distinct and interdependent regulatory mechanisms at the chromatin level for
- NSF-PAR ID:
- 10397453
- 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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• The expression of an intracellular immune receptor gene SNC1 (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 regulate SNC1 expression 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 of SNC1. • Modifier of snc1 (MOS1) constitutes the first module and is required for the interdependent functions of ARABIDOPSIS TRITHORAX-RELATED 7 (ATXR7) and HISTONE MONO-UBIQUITINATION 1 (HUB1) to deposit H3K4me3 and H2Bub1 at the SNC1 locus. 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 repress SNC1 expression under non-pathogenic conditions. The upregulation of SNC1 resulting 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 for SNC1 expression regulation and highlights the intricacy of regulatory mechanisms of NLR expression under different environment.more » « less
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Abstract Intracellular immune receptor nucleotide‐binding leucine‐rich repeats (NLRs) are highly regulated transcriptionally and post‐transcriptionally for balanced plant defence and growth. NLR genes often exist in gene clusters and are usually co‐expressed under various conditions. Despite of intensive studies of regulation of NLR proteins, cis‐acting elements for NLR gene induction, repression or co‐expression are largely unknown due to a larger than usual cis‐region for their expression regulation. Here we used the CRISPR/Cas9 genome editing technology to generate a series of in situ deletions at the endogenous location of a NLR gene
SNC1 residing in theRPP5 gene cluster. These deletions that made in the wild type and theSNC1 constitutive expressing autoimmune mutantbon1 revealed both positive and negative cis‐acting elements forSNC1 expression. Two transcription factors that could bind to these elements were found to have an impact on the expression ofSNC1 . In addition, co‐expression of two genes withSNC1 in the same cluster is found to be mostly dependent on theSNC1 function. Therefore,SNC1 expression is under complex local regulation involving multiple cis elements andSNC1 itself is a critical regulator of gene expression of other NLR genes in the same gene cluster.