Activator recruitment by the general transcription machinery: X-ray structural analysis of the Oct-1 POU domain/human U1 octamer/SNAP190 peptide ternary complex

Genes Dev. 2002 Nov 1;16(21):2772-7. doi: 10.1101/gad.1021002.

Abstract

Transcriptional activation of the human U1 snRNA genes is dependent on a noncanonical octamer element contained within an upstream enhancer. The U1 octamer only weakly recruits the Oct-1 POU domain, although recruitment is stimulated by a peptide containing the Oct-1-binding domain of SNAP190. Structural analysis of the Oct-1 POU domain/U1 octamer/SNAP190 peptide complex revealed that SNAP190 makes extensive protein contacts with the Oct-1 POU-specific domain and with the DNA phosphate backbone within the enhancer. Although SNAP190 and OCA-B both interact with the Oct-1 POU domain through the same Oct-1 interface, a single nucleotide within the U1 octamer ablates OCA-B recruitment without compromising activator recruitment by SNAP190.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • DNA-Binding Proteins / chemistry
  • DNA-Binding Proteins / genetics*
  • Host Cell Factor C1
  • Humans
  • Nucleic Acid Conformation
  • Octamer Transcription Factor-1
  • Protein Binding
  • Protein Conformation
  • Protein Structure, Tertiary / genetics
  • RNA, Small Nuclear / chemistry
  • RNA, Small Nuclear / genetics*
  • Transcription Factors / chemistry
  • Transcription Factors / genetics*
  • Transcriptional Activation*

Substances

  • DNA-Binding Proteins
  • HCFC1 protein, human
  • Host Cell Factor C1
  • Octamer Transcription Factor-1
  • POU2F1 protein, human
  • RNA, Small Nuclear
  • SNAPC4 protein, human
  • Transcription Factors
  • U1 small nuclear RNA