title: What is the driving force for protein import into mitochondria?
abstract: Nuclear-encoded mitochondrial proteins are synthesized in the cytosol as precursors and then imported into mitochondria. Protein import into the matrix space requires the function of the mitochondrial hsp70 (mhsp70) chaperone. mhsp70 is an ATPase that acts in conjunction with two partner proteins: the Tim44 subunit of the inner membrane import complex, and the nucleotide exchange factor mGrpE. A central question concerns how mhsp70 uses the energy of ATP hydrolysis to transport precursor proteins into the matrix. Recent evidence suggests that mhsp70 is a mechanochemical enzyme that actively pulls precursors across the inner membrane.
authors.affiliation: Biozentrum, Universität Basel, Switzerland. horst@ubaclu.unibas.ch
authors.forename: M
authors.initials: M
authors.lastname: Horst
authors.forename: A
authors.initials: A
authors.lastname: Azem
authors.forename: G
authors.initials: G
authors.lastname: Schatz
authors.forename: B S
authors.initials: BS
authors.lastname: Glick
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D001693:Biological Transport, Active; D004734:Energy Metabolism; D005656:Fungal Proteins / Q000378:metabolism; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism; D008564:Membrane Potentials; D008928:Mitochondria / Q000378:metabolism*; D008954:Models, Biological; D018832:Molecular Chaperones / Q000378:metabolism; D011506:Proteins / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism
chemical_list: D005656:Fungal Proteins; D018840:HSP70 Heat-Shock Proteins; C060153:KAR2 protein, yeast; D018832:Molecular Chaperones; D011506:Proteins; D000255:Adenosine Triphosphate