FACT maintains chromatin architecture and thereby stimulates RNA polymerase II pausing during transcription in vivo

Mol Cell. 2024 Jun 6;84(11):2053-2069.e9. doi: 10.1016/j.molcel.2024.05.003. Epub 2024 May 28.

Abstract

Facilitates chromatin transcription (FACT) is a histone chaperone that supports transcription through chromatin in vitro, but its functional roles in vivo remain unclear. Here, we analyze the in vivo functions of FACT with the use of multi-omics analysis after rapid FACT depletion from human cells. We show that FACT depletion destabilizes chromatin and leads to transcriptional defects, including defective promoter-proximal pausing and elongation, and increased premature termination of RNA polymerase II. Unexpectedly, our analysis revealed that promoter-proximal pausing depends not only on the negative elongation factor (NELF) but also on the +1 nucleosome, which is maintained by FACT.

Keywords: FACT; RNA polymerase II; chromatin; nucleosome; promoter-proximal pausing; transcription.

MeSH terms

  • Chromatin Assembly and Disassembly
  • Chromatin* / genetics
  • Chromatin* / metabolism
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism
  • HEK293 Cells
  • HeLa Cells
  • High Mobility Group Proteins* / genetics
  • High Mobility Group Proteins* / metabolism
  • Humans
  • Nucleosomes* / genetics
  • Nucleosomes* / metabolism
  • Promoter Regions, Genetic*
  • RNA Polymerase II* / genetics
  • RNA Polymerase II* / metabolism
  • Transcription Elongation, Genetic
  • Transcription Factors / genetics
  • Transcription Factors / metabolism
  • Transcription Termination, Genetic
  • Transcription, Genetic*
  • Transcriptional Elongation Factors* / genetics
  • Transcriptional Elongation Factors* / metabolism

Substances

  • RNA Polymerase II
  • Transcriptional Elongation Factors
  • Chromatin
  • SSRP1 protein, human
  • Nucleosomes
  • High Mobility Group Proteins
  • DNA-Binding Proteins
  • Transcription Factors
  • negative elongation factor