title: Regulation of DNA Translocation Efficiency within the Chromatin Remodeler RSC/Sth1 Potentiates Nucleosome Sliding and Ejection.
abstract: The RSC chromatin remodeler slides and ejects nucleosomes, utilizing a catalytic subunit (Sth1) with DNA translocation activity, which can pump DNA around the nucleosome. A central question is whether and how DNA translocation is regulated to achieve sliding versus ejection. Here, we report the regulation of DNA translocation efficiency by two domains residing on Sth1 (Post-HSA and Protrusion 1) and by actin-related proteins (ARPs) that bind Sth1. ARPs facilitated sliding and ejection by improving "coupling"-the amount of DNA translocation by Sth1 relative to ATP hydrolysis. We also identified and characterized Protrusion 1 mutations that promote "coupling," and Post-HSA mutations that improve ATP hydrolysis; notably, the strongest mutations conferred efficient nucleosome ejection without ARPs. Taken together, sliding-to-ejection involves a continuum of DNA translocation efficiency, consistent with higher magnitudes of ATPase and coupling activities (involving ARPs and Sth1 domains), enabling the simultaneous rupture of multiple histone-DNA contacts facilitating ejection.
authors.affiliation: Department of Oncological Sciences, Huntsman Cancer Institute and Howard Hughes Medical Institute, University of Utah School of Medicine, Salt Lake City, UT 84112, USA.
authors.forename: Cedric R
authors.initials: CR
authors.lastname: Clapier
authors.affiliation: Department of Oncological Sciences, Huntsman Cancer Institute and Howard Hughes Medical Institute, University of Utah School of Medicine, Salt Lake City, UT 84112, USA.
authors.forename: Margaret M
authors.initials: MM
authors.lastname: Kasten
authors.affiliation: Department of Oncological Sciences, Huntsman Cancer Institute and Howard Hughes Medical Institute, University of Utah School of Medicine, Salt Lake City, UT 84112, USA.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Parnell
authors.affiliation: Department of Oncological Sciences, Huntsman Cancer Institute and Howard Hughes Medical Institute, University of Utah School of Medicine, Salt Lake City, UT 84112, USA.
authors.forename: Ramya
authors.initials: R
authors.lastname: Viswanathan
authors.affiliation: Department of Oncological Sciences, Huntsman Cancer Institute and Howard Hughes Medical Institute, University of Utah School of Medicine, Salt Lake City, UT 84112, USA.
authors.forename: Heather
authors.initials: H
authors.lastname: Szerlong
authors.affiliation: Department of Cell Biology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA.
authors.forename: George
authors.initials: G
authors.lastname: Sirinakis
authors.affiliation: Department of Cell Biology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA.
authors.forename: Yongli
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Oncological Sciences, Huntsman Cancer Institute and Howard Hughes Medical Institute, University of Utah School of Medicine, Salt Lake City, UT 84112, USA. Electronic address: brad.cairns@hci.utah.edu.
authors.forename: Bradley R
authors.initials: BR
authors.lastname: Cairns
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D001665:Binding Sites; D001692:Biological Transport; D018797:Cell Cycle Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D042002:Chromatin Assembly and Disassembly; D004271:DNA, Fungal / Q000235:genetics* / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D006868:Hydrolysis; D008840:Microfilament Proteins / Q000235:genetics / Q000378:metabolism; D009154:Mutation; D009687:Nuclear Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D009707:Nucleosomes / Q000201:enzymology* / Q000235:genetics*; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D013997:Time Factors; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D018797:Cell Cycle Proteins; D004271:DNA, Fungal; D004268:DNA-Binding Proteins; D008840:Microfilament Proteins; D009687:Nuclear Proteins; D009707:Nucleosomes; C103337:RSC complex, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D000255:Adenosine Triphosphate; C077392:STH1 protein, S cerevisiae