The translocon of the mitochondrial outer membrane is functionally equivalent to ER translocon. However, why is Hsc70...

The translocon of the mitochondrial outer membrane is functionally equivalent to ER translocon. However, why is Hsc70 needed for mitochondrial import but not for import into the ER?

Expert Solution

The great majority of mitochondrial proteins are synthesized by cytosolic ribosomes and then imported into the organelle post - translationally. The translocase of the outer membrane (TOM) is a proteinaceous machinery that contains surface receptors for preprotein recognition and also serves as the main entry gateway into mitochondria . Mitochondrial targeting requires various cytosolic factors , in particular the molecular chaperones Hsc70/Hsp70 and Hsp90. The chaperone activity of Hsc70/Hsp70 and Hsp90 occurs in coordinated cycles of ATP hydrolysis and substrate binding , and is regulated by a number of co-chaperone proteins . The import receptor Tom 70 is a member of the tetratricopeptide repeat co-chaperone family and contains a conserved TPR clamp domain for interaction with Hsc70 and Hsp90. Such interaction is essential for the initiation of the import process . This review will discuss the role of Hsc70 and Hsp90 in mitochondrial import and summarize recent progress in understanding these pathways .

gladiator answered 2 years ago

The translocon of the mitochondrial outer membrane is functionally equivalent to ER translocon. However, why is...

The translocon of the mitochondrial outer membrane is functionally equivalent to ER translocon. However, why is Hsc70 needed for mitochondrial import but not for import into the ER?

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