Regulation of Lytic and Non-Lytic Functions of Gasdermin Pores

Abstract

Pyroptosis is a necrotic form of cell death that was initially found to be induced upon activation of inflammatory caspases by inflammasome complexes. Mechanistically, pyroptosis induction requires cleavage of the caspase substrate gasdermin D (GSDMD), and the release of the GSDMD N-terminal fragment, which targets the plasma membrane to form large β-barrel pores. GSDMD shares this pore-forming ability with other gasdermin family members, which induce pyroptosis during infection or upon treatment with chemotherapy drugs. While induction of cell death has been assumed to be the main function of the gasdermin pores, increasing evidence suggests that these pores have non-lytic functions, such as in releasing cytokines or alarmins and in regulating intracellular signaling via ionic fluxes. Here we discuss how gasdermin pore formation is regulated to induce membrane permeabilization or lysis, how gasdermin pores achieve specificity for cargo-release and how cells repair gasdermin-induced damage to the plasma membrane.

Keywords: ESCRT; cell death; gasdermins; inflammasomes; pyroptosis.