The crystal structure of the C-terminal fragment of yeast Hsp40 Ydj1 reveals novel dimerization motif for Hsp40

J Mol Biol. 2005 Mar 4;346(4):1005-11. doi: 10.1016/j.jmb.2004.12.040. Epub 2005 Jan 16.

Abstract

The molecular chaperone Hsp40 functions as a dimer. The dimer formation is critical for Hsp40 molecular chaperone activity to facilitate Hsp70 to refold non-native polypeptides. We have determined the crystal structure of the C-terminal fragment of yeast Hsp40 Ydj1 that is responsible for Ydj1 dimerization by MAD method. The C-terminal fragment of Ydj1 comprises of the domain III of Ydj1 and the Ydj1 C-terminal dimerization motif. The crystal structure indicates that the dimerization motif of type I Hsp40 Ydj1 differs significantly from that of yeast type II Hsp40. The C terminus of type I Hsp40 Ydj1 from one monomer forms beta-strands with the domain III from the other monomer in the homo-dimer. The L372 from Ydj1 C terminus inserts its side-chain into a hydrophobic pocket on domain III. The modeled full-length Ydj1 dimer structure reveals that a large cleft is formed between the two monomers. The domain IIs of Ydj1 monomers that contain the zinc-finger motifs points directly against each other.

Publication types

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

MeSH terms

  • Amino Acid Motifs
  • Crystallography, X-Ray
  • Dimerization
  • HSP40 Heat-Shock Proteins
  • Heat-Shock Proteins / chemistry*
  • Heat-Shock Proteins / metabolism*
  • Models, Molecular
  • Molecular Sequence Data
  • Peptide Fragments / chemistry*
  • Peptide Fragments / metabolism*
  • Protein Structure, Tertiary
  • Saccharomyces cerevisiae / chemistry*
  • Saccharomyces cerevisiae Proteins
  • Sequence Alignment

Substances

  • HSP40 Heat-Shock Proteins
  • Heat-Shock Proteins
  • Peptide Fragments
  • Saccharomyces cerevisiae Proteins
  • YDJ1 protein, S cerevisiae

Associated data

  • PDB/1XAO