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  • The regulation of chromatin configuration at AGAMOUS locus by LFR‐SYD‐containing complex is critical for reproductive organ development in Arabidopsis
Title: The regulation of chromatin configuration at AGAMOUS locus by LFR‐SYD‐containing complex is critical for reproductive organ development in Arabidopsis
SUMMARY

Switch defective/sucrose non‐fermentable (SWI/SNF) chromatin remodeling complexes are evolutionarily conserved, multi‐subunit machinery that play vital roles in the regulation of gene expression by controlling nucleosome positioning and occupancy. However, little is known about the subunit composition of SPLAYED (SYD)‐containing SWI/SNF complexes in plants. Here, we show that theArabidopsis thalianaLeaf and Flower Related (LFR) is a subunit of SYD‐containing SWI/SNF complexes. LFR interacts directly with multiple SWI/SNF subunits, including the catalytic ATPase subunit SYD,in vitroandin vivo. Phenotypic analyses oflfr‐2mutant flowers revealed that LFR is important for proper filament and pistil development, resembling the function of SYD. Transcriptome profiling revealed that LFR and SYD shared a subset of co‐regulated genes. We further demonstrate that the LFR and SYD interdependently activate the transcription ofAGAMOUS(AG), a C‐class floral organ identity gene, by regulating the occupation of nucleosome, chromatin loop, histone modification, and Pol II enrichment on theAGlocus. Furthermore, the chromosome conformation capture (3C) assay revealed that the gene loop atAGlocus is negatively correlated with theAGexpression level, and LFR‐SYD was functional to demolish theAGchromatin loop to promote its transcription. Collectively, these results provide insight into the molecular mechanism of the Arabidopsis SYD‐SWI/SNF complex in the control of higher chromatin conformation of the floral identity gene essential to plant reproductive organ development.

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Award ID(s):
2224729
PAR ID:
10507992
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Wiley-Blackwell for the Society for Experimental Biology
Date Published:
Journal Name:
The Plant Journal
Volume:
116
Issue:
2
ISSN:
0960-7412
Page Range / eLocation ID:
478 to 496
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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