Regulation of DNA Translocation Efficiency within the Chromatin Remodeler RSC/Sth1 Potentiates Nucleosome Sliding and Ejection

Mol Cell. 2016 May 5;62(3):453-461. doi: 10.1016/j.molcel.2016.03.032.

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.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphate / metabolism
  • Binding Sites
  • Biological Transport
  • Cell Cycle Proteins / chemistry
  • Cell Cycle Proteins / genetics
  • Cell Cycle Proteins / metabolism*
  • Chromatin Assembly and Disassembly*
  • DNA, Fungal / genetics*
  • DNA, Fungal / metabolism*
  • DNA-Binding Proteins / chemistry
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism*
  • Hydrolysis
  • Microfilament Proteins / genetics
  • Microfilament Proteins / metabolism
  • Mutation
  • Nuclear Proteins / chemistry
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism*
  • Nucleosomes / enzymology*
  • Nucleosomes / genetics*
  • Protein Binding
  • Protein Interaction Domains and Motifs
  • Saccharomyces cerevisiae / enzymology*
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae Proteins / chemistry
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Time Factors
  • Transcription Factors / chemistry
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*

Substances

  • Cell Cycle Proteins
  • DNA, Fungal
  • DNA-Binding Proteins
  • Microfilament Proteins
  • Nuclear Proteins
  • Nucleosomes
  • RSC complex, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • Transcription Factors
  • Adenosine Triphosphate
  • STH1 protein, S cerevisiae