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The Salmonella Typhimurium Effector SpvB Subverts Host Membrane Trafficking by Targeting Clathrin and AP-1.

ABSTRACT: Salmonella enterica, the etiological agent of gastrointestinal and systemic diseases, translocates a plethora of virulence factors through its type III secretion systems to host cells during infection. Among them, SpvB has been reported to harbor an ADP-ribosyltransferase domain in its C terminus, which destabilizes host cytoskeleton by modifying actin. However, whether this effector targets other host factors as well as the function of its N terminus still remains to be determined. Here, we found that SpvB targets clathrin and its adaptor AP-1 (adaptor protein 1) via interactions with its N-terminal domain. Notably, our data suggest that SpvB-clathrin/AP-1 associations disrupt clathrin-mediated endocytosis and protein secretion pathway as well. In addition, knocking down of AP-1 promotes Salmonella intracellular survival and proliferation in host cells.

SUBMITTER: Yuan Y

PROVIDER: S-EPMC10696399 | biostudies-literature | 2023 Nov

REPOSITORIES: biostudies-literature

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The Salmonella Typhimurium Effector SpvB Subverts Host Membrane Trafficking by Targeting Clathrin and AP-1.

Yuan Yi Y Wang Xinghao X Jin Jie J Tang Zhiheng Z Xian Wei W Zhang Xinyi X Fu Jiaqi J He Kangmin K Liu Xiaoyun X

Molecular & cellular proteomics : MCP 20231102 12

Salmonella enterica, the etiological agent of gastrointestinal and systemic diseases, translocates a plethora of virulence factors through its type III secretion systems to host cells during infection. Among them, SpvB has been reported to harbor an ADP-ribosyltransferase domain in its C terminus, which destabilizes host cytoskeleton by modifying actin. However, whether this effector targets other host factors as well as the function of its N terminus still remains to be determined. Here, we fou ...[more]

PMID: 37924977

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