Secondary structure determination for the Antennapedia homeodomain by nuclear magnetic resonance and evidence for a helix-turn-helix motif

EMBO J. 1988 Dec 20;7(13):4305-9.

Abstract

The homeodomain encoded by the Antennapedia (Antp) gene of Drosophila was studied in aqueous solution by nuclear magnetic resonance (NMR). Sequence-specific resonance assignments have been obtained for the complete polypeptide chain of 68 amino acid residues. The secondary structure determined from nuclear Overhauser effects (NOE) and information about slowly exchanging amide protons includes three helical segments consisting of the residues 10-21, 28-38 and 42-52, respectively. Combination of the presently available NMR data with computer modeling provided preliminary evidence for the presence of a helix-turn-helix motif in the homeodomain. Near the turn, this supersecondary structure appears to be very similar to the DNA binding site in the 434 and P22 c2 repressors, but both helices in the homeodomain include 2-3 additional residues when compared with these prokaryotic DNA-binding proteins.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Computer Simulation
  • DNA-Binding Proteins
  • Drosophila / genetics*
  • Drosophila Proteins
  • Genes, Homeobox*
  • Magnetic Resonance Spectroscopy
  • Models, Molecular
  • Molecular Sequence Data
  • Protein Conformation
  • Transcription Factors* / genetics

Substances

  • DNA-Binding Proteins
  • DTF-1 protein, Drosophila
  • Drosophila Proteins
  • Transcription Factors