Cotranslational sorting and processing of newly synthesized proteins in eukaryotes
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Updated: Jul 11, 2025

Polysome Fractionation and Analysis of Mammalian Translatomes on a Genome-wide Scale
Published on: May 17, 2014
Martin Gamerdinger1, Elke Deuerling1
1Department of Biology, Molecular Microbiology, University of Konstanz, 78457 Konstanz, Germany.
Abstract:
Ribosomes interact with a variety of different protein biogenesis factors that guide newly synthesized proteins to their native 3D shapes and cellular localization. Depending on the type of translated substrate, a distinct set of cotranslational factors must interact with the ribosome in a timely and coordinated manner to ensure proper protein biogenesis. While cytonuclear proteins require cotranslational maturation and folding factors, secretory proteins must be maintained in an unfolded state and processed cotranslationally by transport and membrane translocation factors. Here we explore the specific cotranslational processing steps for cytonuclear, secretory, and membrane proteins in eukaryotes and then discuss how the nascent polypeptide-associated complex (NAC) cotranslationally sorts these proteins into the correct protein biogenesis pathway.
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