Tim14 and Tim16 are essential components of the import motor of the mitochondrial TIM23 preprotein translocase. Tim14 contains a J domain in the matrix space which is anchored in the inner membrane by a transmembrane segment. Tim16 is a J-related protein with a moderately hydrophobic segment at its N terminus. The J and J-like domain function in the regulation of the ATPase activity of the Hsp70 chaperone of the import motor. We report here on the role of the hydrophobic segments of Tim16 and Tim14 in the TIM23 translocase. Yeast cells lacking the hydrophobic N-terminal segment in either Tim16 or Tim14 are viable, but show growth defects and decreased import rates of matrix targeted preproteins into mitochondria. The interaction of the Tim14.Tim16 complex with the core complex of the TIM23 translocase is destabilized in these cells. In particular, the N terminal domain of Tim16 is crucial for the interaction of the Tim14.Tim16 complex with the TIM23 preprotein translocase. Deletion of hydrophobic segments in both, Tim16 and Tim14, is lethal. We conclude that import into the matrix space of mitochondria requires association of the cochaperones Tim16 and Tim14 with the TIM23 preprotein translocase.
|Evidence ID||Analyze ID||Interactor||Interactor Systematic Name||Interactor||Interactor Systematic Name||Type||Assay||Annotation||Action||Modification||Phenotype||Source||Reference||Note|
|Evidence ID||Analyze ID||Gene||Gene Systematic Name||Gene Ontology Term||Gene Ontology Term ID||Qualifier||Aspect||Method||Evidence||Source||Assigned On||Reference||Annotation Extension|
|Evidence ID||Analyze ID||Gene||Gene Systematic Name||Phenotype||Experiment Type||Experiment Type Category||Mutant Information||Strain Background||Chemical||Details||Reference|
|Evidence ID||Analyze ID||Regulator||Regulator Systematic Name||Target||Target Systematic Name||Experiment||Conditions||Strain||Source||Reference|