Subunits of the yeast SWI/SNF complex are members of the actin-related protein (ARP) family

UMMS Affiliation

Program in Molecular Medicine and Department of Biochemistry and Molecular Biology

Publication Date


Document Type



Actins; Adenosine Triphosphatases; Amino Acid Sequence; Chromatin; Chromosomal Proteins, Non-Histone; DNA Primers; DNA-Binding Proteins; Fungal Proteins; Gene Deletion; Genes, Fungal; Macromolecular Substances; Multigene Family; Nuclear Proteins; Peptide Mapping; Phenotype; Polymerase Chain Reaction; Saccharomyces cerevisiae; *Saccharomyces cerevisiae Proteins; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Trans-Activators; Transcription Factors


Life Sciences | Medicine and Health Sciences


The yeast SWI/SNF chromatin remodeling complex is comprised of 11 tightly associated polypeptides (SWI1, SWI2, SWI3, SNF5, SNF6, SNF11, SWP82, SWP73, SWP59, SWP61, and SWP29). We have used matrix-assisted laser desorption ionization time-of-flight mass spectrometry to identify the genes that encode the SWP59 and SWP61 subunits. Surprisingly, we find that SWP59 and SWP61 are encoded by the ARP9 and ARP7 genes, respectively, which encode members of the actin-related protein (ARP) family. Sequence analyses have shown that ARP9 and ARP7 are 24-26% identical (48-51% similar) to yeast actin and that they are likely to maintain the overall actin fold. Deletion of either the ARP9 or ARP7 gene causes typical swi/snf phenotypes, including growth defects on media containing galactose, glycerol, or sucrose as sole carbon sources. ARP9 and ARP7 are also required for expression of an HO-lacZ fusion gene and for full transcriptional enhancement by the GAL4 activator. The identification of two ARP family members as crucial subunits of the SWI/SNF complex suggests that the complex may contain a total of three different ATPase subunits; furthermore, the similarity of ARP7 and ARP9 to the HSP and HSC family of ATPases suggests the possibility that chromatin remodeling by SWI/SNF may involve chaperone-like activities.

DOI of Published Version



J Biol Chem. 1998 Sep 11;273(37):23641-4.

Journal/Book/Conference Title

The Journal of biological chemistry

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