Residue-by-residue analysis of cotranslational membrane protein integration in vivo.

ABSTRACT: We follow the cotranslational biosynthesis of three multispanning Escherichia coli inner membrane proteins in vivo using high-resolution force profile analysis. The force profiles show that the nascent chain is subjected to rapidly varying pulling forces during translation and reveal unexpected complexities in the membrane integration process. We find that an N-terminal cytoplasmic domain can fold in the ribosome exit tunnel before membrane integration starts, that charged residues and membrane-interacting segments such as re-entrant loops and surface helices flanking a transmembrane helix (TMH) can advance or delay membrane integration, and that point mutations in an upstream TMH can affect the pulling forces generated by downstream TMHs in a highly position-dependent manner, sugge

SUBMITTER: Nicolaus F 

PROVIDER: S-EPMC7886326 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature