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Dissecting Innate Immune Signaling in Viral Evasion of Cytokine Production
08:32

Dissecting Innate Immune Signaling in Viral Evasion of Cytokine Production

Published on: March 2, 2014

Yersinia inhibits host signaling by acetylating MAPK kinases

James B Bliska1

  • 1Department of Molecular Genetics and Microbiology, Center for Infectious Diseases, SUNY Stony Brook, Stony Brook, New York 11794-5222, USA. jbliska@ms.cc.sunysb.edu

ACS Chemical Biology
|December 14, 2006
PubMed

Insights

Pathogenic Yersinia bacteria use YopJ (YopP) effector proteins to suppress host immune responses and trigger apoptosis by inactivating key signaling pathways like MAPK.

Area of Science:

  • Microbiology
  • Cellular Biology
  • Immunology

Background:

  • Pathogenic Yersinia species secrete YopJ (YopP) to manipulate host cell functions.
  • YopJ counteracts cytokine production and induces apoptosis in host cells.
  • YopJ targets mitogen-activated protein kinase (MAPK) and nuclear factor kappaB signaling pathways.

Purpose of the Study:

  • To elucidate the mechanism by which YopJ inactivates MAPK signaling pathways.
  • To investigate the enzymatic activity of YopJ concerning ubiquitin (Ub)-like proteins.
  • To understand how YopJ's acetylation activity impacts host cell processes.

Main Methods:

  • Investigated YopJ's interaction with MAPK kinase (MKK) family members.
  • Assessed YopJ's predicted protease activity towards Ub-like proteins.
  • Demonstrated YopJ's ability to acetylate critical serine or threonine residues on MKKs.

Main Results:

  • YopJ directly binds to MKKs, key components of MAPK pathways.
  • YopJ inactivates MKKs through acetylation of specific serine or threonine residues.
  • These findings support the role of YopJ as a ubiquitin-like protease.

Conclusions:

  • YopJ's acetylation of MKKs is a primary mechanism for inhibiting MAPK signaling.
  • This acetylation activity contributes to Yersinia's immune evasion and apoptosis induction.
  • YopJ functions as a ubiquitin-like protease, impacting host cell signaling and survival.

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