The HSA domain binds nuclear actin-related proteins to regulate chromatin-remodeling ATPases.
We identify the helicase-SANT-associated (HSA) domain as the primary binding platform for nuclear actin-related proteins (ARPs) and actin. Individual HSA domains from chromatin remodelers (RSC, yeast SWI-SNF, human SWI-SNF, SWR1 and INO80) or modifiers (NuA4) reconstitute their respective ARP-ARP or ARP-actin modules. In RSC, the HSA domain resides on the catalytic ATPase subunit Sth1. The Sth1 HSA is essential in vivo, and its omission causes the specific loss of ARPs and a moderate reduction in ATPase activity. Genetic selections for arp suppressors yielded specific gain-of-function mutations in two new domains in Sth1, the post-HSA domain and protrusion 1, which are essential for RSC function in vivo but not ARP association. Taken together, we define the role of the HSA domain and provide evidence for a regulatory relationship involving the ARP-HSA module and two new functional domains conserved in remodeler ATPases that contain ARPs.
Szerlong
Heather
H
Howard Hughes Medical Institute, Department of Oncological Sciences, Huntsman Cancer Institute, 2000 Circle of Hope, University of Utah, Salt Lake City, Utah 84112, USA.
Hinata
Kaede
K
Viswanathan
Ramya
R
Erdjument-Bromage
Hediye
H
Tempst
Paul
P
Cairns
Bradley R
BR
D000199:Actins / Q000737:chemistry / Q000378:metabolism*; D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000595:Amino Acid Sequence; D002843:Chromatin / Q000378:metabolism*; D042002:Chromatin Assembly and Disassembly; D003598:Cytoskeletal Proteins / Q000737:chemistry / Q000378:metabolism*; D008969:Molecular Sequence Data; D017434:Protein Structure, Tertiary; D012441:Saccharomyces cerevisiae / Q000737:chemistry / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000378:metabolism*; D016415:Sequence Alignment
D000199:Actins; D002843:Chromatin; D003598:Cytoskeletal Proteins; D029701:Saccharomyces cerevisiae Proteins; D000251:Adenosine Triphosphatases