title: A new, highly conserved domain in Swi2/Snf2 is required for SWI/SNF remodeling.
abstract: SWI/SNF is an ATP-dependent remodeler that mobilizes nucleosomes and has important roles in gene regulation. The catalytic subunit of SWI/SNF has an ATP-dependent DNA translocase domain that is essential for remodeling. Besides the DNA translocase domain there are other domains in the catalytic subunit of SWI/SNF that have important roles in mobilizing nucleosomes. One of these domains, termed SnAC (Snf2 ATP Coupling), is conserved in all eukaryotic SWI/SNF complexes and is located between the ATPase and A-T hook domains. Here, we show that the SnAC domain is essential for SWI/SNF activity. The SnAC domain is not required for SWI/SNF complex integrity, efficient nucleosome binding, or recruitment by acidic transcription activators. The SnAC domain is however required in vivo for transcription regulation by SWI/SNF as seen by alternative carbon source growth assays, northern analysis, and genome-wide expression profiling. The ATPase and nucleosome mobilizing activities of SWI/SNF are severely affected when the SnAC domain is removed or mutated. The SnAC domain positively regulates the catalytic activity of the ATPase domain of SWI/SNF to hydrolyze ATP without significantly affecting its affinity for ATP.
authors.affiliation: Department of Biochemistry and Molecular Biology, Southern Illinois University School of Medicine, Neckers Building, Carbondale, IL 62901-4413, USA.
authors.forename: Payel
authors.initials: P
authors.lastname: Sen
authors.forename: Sujana
authors.initials: S
authors.lastname: Ghosh
authors.forename: B Franklin
authors.initials: BF
authors.lastname: Pugh
authors.forename: Blaine
authors.initials: B
authors.lastname: Bartholomew
mesh_terms: D000251:Adenosine Triphosphatases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D000818:Animals; D042002:Chromatin Assembly and Disassembly; D017124:Conserved Sequence; D004247:DNA / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D006801:Humans; D008969:Molecular Sequence Data; D009707:Nucleosomes / Q000378:metabolism; D017434:Protein Structure, Tertiary; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism
chemical_list: D009707:Nucleosomes; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D004247:DNA; D000251:Adenosine Triphosphatases; C499333:SNF2 protein, S cerevisiae