Principles of ER cotranslational translocation revealed by proximity-specific ribosome profiling.

ABSTRACT: Localized protein synthesis is a fundamental mechanism for creating distinct subcellular environments. Here we developed a generalizable proximity-specific ribosome profiling strategy that enables global analysis of translation in defined subcellular locations. We applied this approach to the endoplasmic reticulum (ER) in yeast and mammals. We observed the large majority of secretory proteins to be cotranslationally translocated, including substrates capable of posttranslational insertion in vitro. Distinct translocon complexes engaged nascent chains at different points during synthesis. Whereas most proteins engaged the ER immediately after or even before signal sequence (SS) emergence, a class of Sec66-dependent proteins entered with a looped SS conformation. Finally, we observed rapid r

SUBMITTER: Jan CH 

PROVIDER: S-EPMC4285348 | biostudies-literature | 2014 Nov

REPOSITORIES: biostudies-literature