NAC and Zuotin/Hsp70 chaperone systems coexist at the ribosome tunnel exit in vivo.

ABSTRACT: The area surrounding the tunnel exit of the 60S ribosomal subunit is a hub for proteins involved in maturation and folding of emerging nascent polypeptide chains. How different factors vie for positioning at the tunnel exit in the complex cellular environment is not well understood. We used in vivo site-specific cross-linking to approach this question, focusing on two abundant factors-the nascent chain-associated complex (NAC) and the Hsp70 chaperone system that includes the J-domain protein co-chaperone Zuotin. We found that NAC and Zuotin can cross-link to each other at the ribosome, even when translation initiation is inhibited. Positions yielding NAC-Zuotin cross-links indicate that when both are present the central globular domain of NAC is modestly shifted from the mutually exclusive

SUBMITTER: Ziegelhoffer T 

PROVIDER: S-EPMC11014269 | biostudies-literature | 2024 Apr

REPOSITORIES: biostudies-literature