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Actin Assembly around the Shigella-Containing Vacuole Promotes Successful Infection.

ABSTRACT: The enteroinvasive bacterium Shigella flexneri forces its uptake into non-phagocytic host cells through the translocation of T3SS effectors that subvert the actin cytoskeleton. Here, we report de novo actin polymerization after cellular entry around the bacterium-containing vacuole (BCV) leading to the formation of a dynamic actin cocoon. This cocoon is thicker than any described cellular actin structure and functions as a gatekeeper for the cytosolic access of the pathogen. Host CDC42, TOCA-1, N-WASP, WIP, the Arp2/3 complex, cortactin, coronin, and cofilin are recruited to the actin cocoon. They are subverted by T3SS effectors, such as IpgD, IpgB1, and IcsB. IcsB immobilizes components of the actin polymerization machinery at the BCV dependent on its fatty acyltransferase activity. This represents a unique microbial subversion strategy through localized entrapment of host actin regulators causing massive actin assembly. We propose that the cocoon promotes subsequent invasion steps for successful Shigella infection.

SUBMITTER: Kuhn S

PROVIDER: S-EPMC7225751 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Actin Assembly around the Shigella-Containing Vacuole Promotes Successful Infection.

Kühn Sonja S Bergqvist John J Gil Magdalena M Valenzuela Camila C Barrio Laura L Lebreton Stéphanie S Zurzolo Chiara C Enninga Jost J

Cell reports 20200501 6

The enteroinvasive bacterium Shigella flexneri forces its uptake into non-phagocytic host cells through the translocation of T3SS effectors that subvert the actin cytoskeleton. Here, we report de novo actin polymerization after cellular entry around the bacterium-containing vacuole (BCV) leading to the formation of a dynamic actin cocoon. This cocoon is thicker than any described cellular actin structure and functions as a gatekeeper for the cytosolic access of the pathogen. Host CDC42, TOCA-1, ...[more]

PMID: 32402280

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Dataset Information

Actin Assembly around the Shigella-Containing Vacuole Promotes Successful Infection.

Publications

Actin Assembly around the Shigella-Containing Vacuole Promotes Successful Infection.

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