The SAS Chromatin-Remodeling Complex Mediates Inflorescence-Specific Chromatin Accessibility for Transcription Factor Binding

Abstract

While the role of transcription factors in flower development is well understood, the effect of chromatin remodeling on this process remains largely unclear. We conducted a comprehensive analysis to investigate the genome-wide effects of the SAS, BAS, and MAS-type SWI/SNF complexes on chromatin accessibility and gene transcription in both seedlings and inflorescences ofArabidopsis thaliana. Our results indicate that the SAS complex plays a crucial role in promoting the accessibility of genes involved in flower development. Within inflorescences, the SAS complex binds to numerous genes related to flower development and is responsible for establishing chromatin accessibility at distal promoter and upstream intergenic regions of these genes. In contrast, the BAS and MAS complexes exhibit minimal involvement in regulating the accessibility of these genes. Notably, the genomic regions bound by the SAS complex are enriched with sites occupied by multiple MADS family transcription factors associated with flower development. This study highlights the significant role of the SAS complex in modulating chromatin accessibility during flower development, providing insights into the dynamic regulation of chromatin remodeling during plant development.One-sentence summaryThe SAS-type SWI/SNF complex establishes chromatin accessibility at distal promoter and upstream intergenic regions of flower development-related genes, thereby contributing to flower development.