Palmitoylation of gasdermin D directs its membrane translocation and pore formation in pyroptosis

Insights

Gasdermin D (GSDMD) palmitoylation is essential for its membrane translocation and pore formation, driving pyroptosis. Inhibiting this process reduces inflammation and improves survival in sepsis models.

Area of Science:

  • Immunology
  • Cell Biology
  • Biochemistry

Background:

  • Gasdermin D (GSDMD)-mediated pyroptosis is crucial for inflammation and host defense.
  • Caspase-cleaved GSDMD N-terminal domain (GSDMD-NT) triggers plasma membrane perforation, leading to pyroptotic cell death and release of IL-1β and IL-18.
  • The precise mechanisms governing GSDMD membrane translocation and pore formation remain incompletely understood.

Approach:

  • Utilized a proteomics approach to identify GSDMD-binding partners.
  • Investigated the role of post-translational modifications, specifically palmitoylation, in GSDMD function.
  • Employed pharmacological inhibitors and peptide-based strategies to modulate GSDMD palmitoylation.

Key Points:

  • Identified fatty acid synthase (FASN) as a GSDMD-binding partner.
  • Demonstrated that GSDMD palmitoylation at Cys191/Cys192 (human/mouse) facilitates GSDMD-NT membrane translocation.
  • Showcased that GSDMD lipidation, dependent on ZDHHC5/9 and LPS-induced ROS, is vital for GSDMD pore-forming activity and pyroptosis.

Conclusions:

  • Established GSDMD-NT palmitoylation as a critical regulatory mechanism for GSDMD membrane localization and activation.
  • Inhibiting GSDMD palmitoylation suppressed pyroptosis, IL-1β release, mitigated organ damage, and improved survival in septic mice.
  • Highlighted GSDMD palmitoylation as a potential therapeutic target for inflammatory and infectious diseases.

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