IRE-1α is a key switch of pyroptosis and necroptosis in mice by dominating Gasdermin D

Abstract Necroptosis and pyroptosis are lytic and inflammatory types of programmed cell death that require the membrane destruction predominantly driven by the mixed lineage kinase domain-like (MLKL) and gasdermin D (GSDMD) proteins, respectively. However, the crosstalk between them remains largely unknown. Here, our research discloses that endoplasmic reticulumn transmembrane protein inositol-requiring enzyme-1α (IRE-1α) is a potential modulator of both necroptosis and pyroptosis, paricularly in liver pathology. Interestingly, enhanced expression of IRE-1α triggers hepatic pyroptosis, while defective IRE-1α level activates hepatic necroptosis, and both processes are closed related to the activity of GSDMD in mice. To elucidate unknown crosstalk, by using pharmacological and genetic methods, we first demonstrated that IRE-1α suppresses necroptosis by promoting the expression of GSDMD and cleaves caspase-8 and by inhibiting the expression of receptor-interacting serine/threonine-protein kinase 1 (RIPK1), RIPK3 and MLKL. Unexpectedly, excess IRE-1α initiates pyroptosis by increasing GSDMD and NLRP3 levels. Our work clearly provides insight into the modulation of IRE-1α to dominate necroptosis and pyroptosis and suggests that IRE-1α may be a promising therapeutic target for drug discovery in both types of tissue injuries.