Component of the chromatin structure remodeling complex (RSC), which is involved in transcription regulation and nucleosome positioning. RSC is responsible for the transfer of a histone octamer from a nucleosome core particle to naked DNA. The reaction requires ATP and involves an activated RSC-nucleosome intermediate. Remodeling reaction also involves DNA translocation, DNA twist and conformational change. As a reconfigurer of centromeric and flanking nucleosomes, RSC complex is required both for proper kinetochore function in chromosome segregation and, via a PKC1-dependent signaling pathway, for organization of the cellular cytoskeleton. This subunit is involved in transcriptional regulation. Heterodimer of ARP9 and ARP7 functions with HMG box proteins to facilitate proper chromatin architecture. Heterodimer formation is necessary for assembly into RSC complex. Part of the SWI/SNF complex, an ATP-dependent chromatin remodeling complex, is required for the positive and negative regulation of gene expression of a large number of genes. It changes chromatin structure by altering DNA-histone contacts within a nucleosome, leading eventually to a change in nucleosome position, thus facilitating or repressing binding of gene-specific transcription factors. Forms a heterodimer with ARP7. Interacts with LDB7 and NPL6. Component of the two forms of the RSC complex composed of at least either RSC1 or RSC2, and ARP7, ARP9, LDB7, NPL6, RSC3, RSC30, RSC4, RSC58, RSC6, RSC8, RSC9, SFH1, STH1, HTL1 and probably RTT102. The complexes interact with histone and histone variant components of centromeric chromatin. Component of the SWI/SNF global transcription activator complex. The 1.14 MDa SWI/SNF complex is composed of 11 different subunits: one copy each of SWI1, SNF2/SWI2, SNF5, SNF12/SWP73, ARP7/SWP61, ARP9/SWP59; two copies each of SWI3, SNF6, SNF11, SWP82; and three copies of TAF14/SWP29. Localizes to centromeric and flanking chromatin. Association with these loci is dependent on STH1. Present with 1790 molecules/cell in log phase SD medium. Belongs to the actin family.