Structural basis for the function of Tim50 in the mitochondrial presequence translocase

J Mol Biol. 2011 Aug 19;411(3):513-9. doi: 10.1016/j.jmb.2011.06.020. Epub 2011 Jun 17.

Abstract

Many mitochondrial proteins are synthesized as preproteins carrying amino-terminal presequences in the cytosol. The preproteins are imported by the translocase of the outer mitochondrial membrane and the presequence translocase of the inner membrane. Tim50 and Tim23 transfer preproteins through the intermembrane space to the inner membrane. We report the crystal structure of the intermembrane space domain of yeast Tim50 to 1.83 Å resolution. A protruding β-hairpin of Tim50 is crucial for interaction with Tim23, providing a molecular basis for the cooperation of Tim50 and Tim23 in preprotein translocation to the protein-conducting channel of the mitochondrial inner membrane.

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

  • Crystallization
  • Crystallography, X-Ray
  • Membrane Transport Proteins / chemistry*
  • Membrane Transport Proteins / metabolism
  • Mitochondria
  • Mitochondrial Membrane Transport Proteins / chemistry*
  • Mitochondrial Membrane Transport Proteins / metabolism
  • Mitochondrial Membranes / metabolism
  • Mitochondrial Proteins / chemistry
  • Mitochondrial Proteins / metabolism
  • Peptidyl Transferases / chemistry
  • Peptidyl Transferases / metabolism
  • Protein Precursors / analysis
  • Protein Structure, Quaternary
  • Protein Structure, Tertiary
  • Saccharomyces cerevisiae / cytology
  • Saccharomyces cerevisiae / physiology*
  • Saccharomyces cerevisiae Proteins / chemistry*
  • Saccharomyces cerevisiae Proteins / metabolism

Substances

  • Membrane Transport Proteins
  • Mitochondrial Membrane Transport Proteins
  • Mitochondrial Proteins
  • Protein Precursors
  • Saccharomyces cerevisiae Proteins
  • TIM23 protein, S cerevisiae
  • TIM50 protein, S cerevisiae
  • Peptidyl Transferases

Associated data

  • PDB/3QLE