Identification and structural characterization of a CBP/p300-binding domain from the ETS family transcription factor GABP alpha

J Mol Biol. 2008 Mar 28;377(3):636-46. doi: 10.1016/j.jmb.2008.01.054. Epub 2008 Jan 30.

Abstract

Using NMR spectroscopy, we identified and characterized a previously unrecognized structured domain near the N-terminus (residues 35-121) of the ETS family transcription factor GABP alpha. The monomeric domain folds as a five-stranded beta-sheet crossed by a distorted helix. Although globally resembling ubiquitin, the GABP alpha fragment differs in its secondary structure topology and thus appears to represent a new protein fold that we term the OST (On-SighT) domain. The surface of the GABP alpha OST domain contains two predominant clusters of negatively-charged residues suggestive of electrostatically driven interactions with positively-charged partner proteins. Following a best-candidate approach to identify such a partner, we demonstrated through NMR-monitored titrations and glutathione S-transferase pulldown assays that the OST domain binds to the CH1 and CH3 domains of the co-activator histone acetyltransferase CBP/p300. This provides a direct structural link between GABP and a central component of the transcriptional machinery.

Publication types

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

MeSH terms

  • Animals
  • Binding Sites
  • GA-Binding Protein Transcription Factor / chemistry*
  • Mice
  • Nuclear Magnetic Resonance, Biomolecular
  • Protein Folding
  • Protein Structure, Secondary
  • Protein Structure, Tertiary
  • p300-CBP Transcription Factors / chemistry*

Substances

  • GA-Binding Protein Transcription Factor
  • p300-CBP Transcription Factors

Associated data

  • PDB/2JUO