Fine interaction profiling of VemP and mechanisms responsible for its translocation-coupled arrest-cancelation

Miyazaki, R.; Akiyama, Y.; Mori, H.

doi:10.1101/2020.09.12.294835

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bioRxiv · 10.1101/2020.09.12.294835

Fine interaction profiling of VemP and mechanisms responsible for its translocation-coupled arrest-cancelation

Miyazaki, R.·Akiyama, Y.·Mori, H.

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Abstract

Bacterial cells utilize monitoring substrates, which undergo force-sensitive translation elongation arrest, to feedback-regulate a Sec-related gene. Vibrio alginolyticus VemP controls the expression of SecD/F that stimulates a late step of translocation by undergoing export-regulated elongation arrest. Here, we attempted at delineating the pathway of the VemP nascent-chain interaction with Sec-related factors, and identified the signal recognition particle (SRP) and PpiD (a membrane-anchored periplasmic chaperone) in addition to other translocon components and a ribosomal protein as interacting partners. Our results showed that SRP is required for the membrane-targeting of VemP, whereas PpiD acts cooperatively with SecD/F in the VemP arrest-cancelation. We also identified the conserved Arg-85 residue in VemP as an essential element for the regulated arrest-cancelation of VemP. We propose a scheme of the arrest-cancelation processes of VemP, which likely monitors late steps in the protein translocation pathway.

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Miyazaki, R., Akiyama, Y., Mori, H.. 2020-09-12. Fine interaction profiling of VemP and mechanisms responsible for its translocation-coupled arrest-cancelation. https://doi.org/10.1101/2020.09.12.294835

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