title: Unique, shared, and redundant roles for the Arabidopsis SWI/SNF chromatin remodeling ATPases BRAHMA and SPLAYED.
abstract: Chromatin remodeling is emerging as a central mechanism for patterning and differentiation in multicellular eukaryotes. SWI/SNF chromatin remodeling ATPases are conserved in the animal and plant kingdom and regulate transcriptional programs in response to endogenous and exogenous cues. In contrast with their metazoan orthologs, null mutants in two Arabidopsis thaliana SWI/SNF ATPases, BRAHMA (BRM) and SPLAYED (SYD), are viable, facilitating investigation of their role in the organism. Previous analyses revealed that syd and brm null mutants exhibit both similar and distinct developmental defects, yet the functional relationship between the two closely related ATPases is not understood. Another central question is whether these proteins act as general or specific transcriptional regulators. Using global expression studies, double mutant analysis, and protein interaction assays, we find overlapping functions for the two SWI/SNF ATPases. This partial diversification may have allowed expansion of the SWI/SNF ATPase regulatory repertoire, while preserving essential ancestral functions. Moreover, only a small fraction of all genes depends on SYD or BRM for expression, indicating that these SWI/SNF ATPases exhibit remarkable regulatory specificity. Our studies provide a conceptual framework for understanding the role of SWI/SNF chromatin remodeling in regulation of Arabidopsis development.
authors.affiliation: Department of Biology, University of Pensylvania, Philadelphia, Penslvania 19104, USA.
authors.forename: Staver
authors.initials: S
authors.lastname: Bezhani
authors.forename: Cara
authors.initials: C
authors.lastname: Winter
authors.forename: Steve
authors.initials: S
authors.lastname: Hershman
authors.forename: John D
authors.initials: JD
authors.lastname: Wagner
authors.forename: John F
authors.initials: JF
authors.lastname: Kennedy
authors.forename: Chang Seob
authors.initials: CS
authors.lastname: Kwon
authors.forename: Jennifer
authors.initials: J
authors.lastname: Pfluger
authors.forename: Yanhui
authors.initials: Y
authors.lastname: Su
authors.forename: Doris
authors.initials: D
authors.lastname: Wagner
mesh_terms: D000251:Adenosine Triphosphatases / Q000235:genetics / Q000378:metabolism*; D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics* / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D042002:Chromatin Assembly and Disassembly; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D017930:Genes, Reporter; D008969:Molecular Sequence Data; D009154:Mutation; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D020411:Oligonucleotide Array Sequence Analysis; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: C463463:ATSWI3B protein, Arabidopsis; D029681:Arabidopsis Proteins; D009687:Nuclear Proteins; D016601:RNA-Binding Proteins; D000251:Adenosine Triphosphatases; C452429:SPLAYED protein, Arabidopsis; C514541:BRM protein, Arabidopsis