Dataset Information

MYO6 is targeted by Salmonella virulence effectors to trigger PI3-kinase signaling and pathogen invasion into host cells.

ABSTRACT: To establish infections, Salmonella injects virulence effectors that hijack the host actin cytoskeleton and phosphoinositide signaling to drive pathogen invasion. How effectors reprogram the cytoskeleton network remains unclear. By reconstituting the activities of the Salmonella effector SopE, we recapitulated Rho GTPase-driven actin polymerization at model phospholipid membrane bilayers in cell-free extracts and identified the network of Rho-recruited cytoskeleton proteins. Knockdown of network components revealed a key role for myosin VI (MYO6) in Salmonella invasion. SopE triggered MYO6 localization to invasion foci, and SopE-mediated activation of PAK recruited MYO6 to actin-rich membranes. We show that the virulence effector SopB requires MYO6 to regulate the localization of PIP3 and PI(3)P phosphoinositides and Akt activation. SopE and SopB target MYO6 to coordinate phosphoinositide production at invasion foci, facilitating the recruitment of cytoskeleton adaptor proteins to mediate pathogen uptake.

SUBMITTER: Brooks AB

PROVIDER: S-EPMC5393208 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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MYO6 is targeted by Salmonella virulence effectors to trigger PI3-kinase signaling and pathogen invasion into host cells.

Brooks Andrew B E AB Humphreys Daniel D Singh Vikash V Davidson Anthony C AC Arden Susan D SD Buss Folma F Koronakis Vassilis V

Proceedings of the National Academy of Sciences of the United States of America 20170327 15

To establish infections, Salmonella injects virulence effectors that hijack the host actin cytoskeleton and phosphoinositide signaling to drive pathogen invasion. How effectors reprogram the cytoskeleton network remains unclear. By reconstituting the activities of the Salmonella effector SopE, we recapitulated Rho GTPase-driven actin polymerization at model phospholipid membrane bilayers in cell-free extracts and identified the network of Rho-recruited cytoskeleton proteins. Knockd ...[more]

PMID: 28348208

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Dataset Information

MYO6 is targeted by Salmonella virulence effectors to trigger PI3-kinase signaling and pathogen invasion into host cells.

Publications

MYO6 is targeted by <i>Salmonella</i> virulence effectors to trigger PI3-kinase signaling and pathogen invasion into host cells.

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