Post-translational protein translocation: not all hsc70s are created equal.

Hsc70s in the yeast endoplasmic reticulum (ER) and mitochondria interact with membrane-associated components of the translocation machinery and are required for post-translational protein import. Although it has been proposed that the mitochondrial and ER machines function similarly, a variety of experiments suggest that BiP, the ER hsc70, might play a more elaborate role.