Multivalent Interactions between Chaperone and Ribosome-Nascent Chain Complex Revealed by High-Speed AFM and MD Simulations.

ABSTRACT: Trigger Factor (TF) is a primary ATP-independent molecular chaperone in bacteria that engages nascent polypeptide chains emerging from the ribosomal exit tunnel to assist their folding. However, the real-time behavior of TF during active translation under near-physiological conditions remains elusive. Here, we employ high-speed atomic force microscopy (HS-AFM) imaging to visualize TF dynamics on intact Escherichia coli ribosomes in real time. We observe that TF transitions between compact and extended conformations and forms stable and transient contacts near ribosomal proteins uL23 and bL17, respectively. Interestingly, TFs engage distinct regions of the same ribosome-nascent chain complex, with one TF binding near the nascent chain and another near bL17, revealing multivalent inte

SUBMITTER: Nunez E 

PROVIDER: S-EPMC12752688 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature