6ao4
Crystal structure of the human gasdermin D C-terminal domainCrystal structure of the human gasdermin D C-terminal domain
Structural highlights
FunctionGSDMD_HUMAN Gasdermin-D, N-terminal: Promotes pyroptosis in response to microbial infection and danger signals. Produced by the cleavage of gasdermin-D by inflammatory caspases CASP1 or CASP4 in response to canonical, as well as non-canonical (such as cytosolic LPS) inflammasome activators (PubMed:26375003, PubMed:26375259, PubMed:27418190). After cleavage, moves to the plasma membrane where it strongly binds to inner leaflet lipids, including monophosphorylated phosphatidylinositols, such as phosphatidylinositol 4-phosphate, bisphosphorylated phosphatidylinositols, such as phosphatidylinositol (4,5)-bisphosphate, as well as phosphatidylinositol (3,4,5)-bisphosphate, and more weakly to phosphatidic acid and phosphatidylserine (PubMed:27281216). Homooligomerizes within the membrane and forms pores of 10 - 15 nanometers (nm) of inner diameter, possibly allowing the release of mature IL1B and triggering pyroptosis (PubMed:27418190, PubMed:27281216). Exhibits bactericidal activity. Gasdermin-D, N-terminal released from pyroptotic cells into the extracellular milieu rapidly binds to and kills both Gram-negative and Gram-positive bacteria, without harming neighboring mammalian cells, as it does not disrupt the plasma membrane from the outside due to lipid-binding specificity (PubMed:27281216). Under cell culture conditions, also active against intracellular bacteria, such as Listeria monocytogenes (By similarity). Strongly binds to bacterial and mitochondrial lipids, including cardiolipin. Does not bind to unphosphorylated phosphatidylinositol, phosphatidylethanolamine nor phosphatidylcholine (PubMed:27281216).[UniProtKB:Q9D8T2][1] [2] [3] [4] Publication Abstract from PubMedPyroptosis is an inflammatory form of programmed cell death that plays important roles in immune protection against infections and in inflammatory disorders. Gasdermin D (GSDMD) is an executor of pyroptosis upon cleavage by caspases-1/4/5/11 following canonical and noncanonical inflammasome activation. GSDMD N-terminal domain assembles membrane pores to induce cytolysis, whereas its C-terminal domain inhibits cell death through intramolecular association with the N domain. The molecular mechanisms of autoinhibition for GSDMD are poorly characterized. Here we report the crystal structures of the human and murine GSDMD C-terminal domains, which differ from those of the full-length murine GSDMA3 and the human GSDMB C-terminal domain. Mutations of GSDMD C-domain residues predicted to locate at its interface with the N-domain enhanced pyroptosis. Our results suggest that GSDMDs may employ a distinct mode of intramolecular domain interaction and autoinhibition, which may be relevant to its unique role in pyroptosis downstream of inflammasome activation. Structures of the Gasdermin D C-Terminal Domains Reveal Mechanisms of Autoinhibition.,Liu Z, Wang C, Rathkey JK, Yang J, Dubyak GR, Abbott DW, Xiao TS Structure. 2018 Mar 14. pii: S0969-2126(18)30082-0. doi:, 10.1016/j.str.2018.03.002. PMID:29576317[5] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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