Biogenesis of Secretory Proteins in Eukaryotic and Prokaryotic Cells

Abstract

Secretory proteins targeted to extracytoplasmic locations must first travel across the endoplasmic reticulum (ER) membrane in eukaryotic cells or the cytoplasmic membrane in prokaryotic cells. During biogenesis, the nascent polypeptide chains of these proteins are usually first recognized and translocated co- or post-translationally through certain protein-conducting channels located at the membranes, after which the nascent proteins are converted to their mature forms (to be folded, assembled and modified, etc.). Here we summarize current knowledge of the common mechanisms of action among the protein factors and machinery that facilitate targeting and quality control for newly synthesized secretory proteins in eukaryotic and prokaryotic cells.