Journal ArticleThe regulation of chromatin configuration at <i>AGAMOUS</i> locus by LFR‐SYD‐containing complex is critical for reproductive organ development in ArabidopsisLin, Xiaowei; Yuan, Tingting; Guo, Hong; Guo, Yi; Yamaguchi, Nobutoshi; Wang, Shuge; Zhang, Dongxia; Qi, Dongmei; Li, Jiayu; Chen, Qiang; Liu, Xinye; Zhao, Long; Xiao, Jun; Wagner, Doris; Cui, Sujuan; Zhao, Hongtao<title>SUMMARY</title> <p>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 the<italic>Arabidopsis thaliana</italic>Leaf 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,<italic>in vitro</italic>and<italic>in vivo</italic>. Phenotypic analyses of<italic>lfr‐2</italic>mutant 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 of<italic>AGAMOUS</italic>(<italic>AG</italic>), a C‐class floral organ identity gene, by regulating the occupation of nucleosome, chromatin loop, histone modification, and Pol II enrichment on the<italic>AG</italic>locus. Furthermore, the chromosome conformation capture (3C) assay revealed that the gene loop at<italic>AG</italic>locus is negatively correlated with the<italic>AG</italic>expression level, and LFR‐SYD was functional to demolish the<italic>AG</italic>chromatin 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.</p>Wiley-Blackwell for the Society for Experimental Biology2023-10-0110507992The Plant Journal1162478 to 4960960-7412https://doi.org/10.1111/tpj.163852224729National Science Foundation