LFR is functionally associated with AS2 to mediate leaf development in Arabidopsis

• Published in: The Plant journal : for cell and molecular biology Vol. 95; no. 4; pp. 598 - 612
• Main Authors: Lin, Xiaowei, Gu, Dandan, Zhao, Hongtao, Peng, Yue, Zhang, Guofang, Yuan, Tingting, Li, Mengge, Wang, Zhijuan, Wang, Xiutang, Cui, Sujuan
• Format: Journal Article
• Language: English
• Published: England Blackwell Publishing Ltd 01.08.2018
• Subjects: Arabidopsis thaliana; ASYMMETRIC LEAVES2 (AS2); BREVIPEDICELLUS (BP); Chromatin; Ectopic expression; leaf; Leaf and Flower Related (LFR); Leaves; Morphogenesis; Mutants; Organs; SWI/SNF complex; Transcription factors; Vascular system (plant anatomy); Arabidopsis thaliana; BREVIPEDICELLUS (BP); ASYMMETRIC LEAVES2 (AS2); Leaf and Flower Related (LFR); leaf
• ISSN: 0960-7412; 1365-313X
• DOI: 10.1111/tpj.13973

Summary Leaves are essential organs for plants. We previously identified a functional gene possibly encoding a component of the SWI/SNF complex named Leaf and Flower Related (LFR) in Arabidopsis thaliana. Loss‐of‐function mutants of LFR displayed obvious defects in leaf morphogenesis, indicating its vital role in leaf development. Here an allelic null mutant of ASYMMETRIC LEAVES2 (AS2), as2‐6, was isolated as an enhancer of lfr‐1 in petiole length, vasculature pattern and leaf margin development. The lfr as2 double‐mutants showed enhanced ectopic expression of BREVIPEDICELLUS (BP) compared with each of the single‐mutants, which is consistent with their synergistic genetic enhancement in multiple BP‐dependent development processes. Moreover, LFR and several putative subunits of the SWI/SNF complex interacted physically with AS2. LFR associated with BP chromatin in an AS1–AS2‐dependent manner to promote the nucleosome occupancy for appropriate BP repression in leaves. Taken together, our findings reveal that LFR and the SWI/SNF complex play roles in leaf development at least partly by repressing BP transcription as interacting factors of AS2, which expounds our understanding of BP repression at the chromatin structure level in leaf development. Significance Statement We demonstrate that transcription factor AS2 interacts with LFR and SWI/SNF complex to suppress BP transcription through modulating nucleosome occupancy in leaf development. These results uncover an epigenetic chromatin remodeling mechanism for BP repression.