The box C/D snoRNP assembly factor Bcd1 interacts with the histone chaperone Rtt106 and controls its transcription dependent activity

Nat Commun. 2021 Mar 25;12(1):1859. doi: 10.1038/s41467-021-22077-4.

Abstract

Biogenesis of eukaryotic box C/D small nucleolar ribonucleoproteins initiates co-transcriptionally and requires the action of the assembly machinery including the Hsp90/R2TP complex, the Rsa1p:Hit1p heterodimer and the Bcd1 protein. We present genetic interactions between the Rsa1p-encoding gene and genes involved in chromatin organization including RTT106 that codes for the H3-H4 histone chaperone Rtt106p controlling H3K56ac deposition. We show that Bcd1p binds Rtt106p and controls its transcription-dependent recruitment by reducing its association with RNA polymerase II, modulating H3K56ac levels at gene body. We reveal the 3D structures of the free and Rtt106p-bound forms of Bcd1p using nuclear magnetic resonance and X-ray crystallography. The interaction is also studied by a combination of biophysical and proteomic techniques. Bcd1p interacts with a region that is distinct from the interaction interface between the histone chaperone and histone H3. Our results are evidence for a protein interaction interface for Rtt106p that controls its transcription-associated activity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Proliferation / physiology
  • Chromatin / genetics
  • Chromatin Assembly and Disassembly / genetics*
  • Crystallography, X-Ray
  • Histones / metabolism
  • Molecular Chaperones / metabolism*
  • Nuclear Magnetic Resonance, Biomolecular
  • RNA Polymerase II / metabolism
  • RNA-Binding Proteins / metabolism*
  • Ribonucleoproteins, Small Nucleolar / genetics
  • Ribonucleoproteins, Small Nucleolar / metabolism
  • Ribosomal Proteins / genetics
  • Ribosomal Proteins / metabolism
  • Ribosomes / metabolism
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Transcription, Genetic / genetics
  • Transcriptional Activation / physiology*

Substances

  • Bcd1 protein, S cerevisiae
  • Chromatin
  • Histones
  • Molecular Chaperones
  • RNA-Binding Proteins
  • RSA1 protein, S cerevisiae
  • Ribonucleoproteins, Small Nucleolar
  • Ribosomal Proteins
  • Rtt106 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • RNA Polymerase II