Research ArticleCELL DEATH

Coral gasdermin triggers pyroptosis

See allHide authors and affiliations

Science Immunology  04 Dec 2020:
Vol. 5, Issue 54, eabd2591
DOI: 10.1126/sciimmunol.abd2591

You are currently viewing the abstract.

View Full Text

Log in to view the full text

Log in through your institution

Log in through your institution

Corals catch fire

Pyroptosis is a form of inflammatory cell death that occurs in response to pathogen infection and results in the release of intracellular contents mediated by the pore-forming gasdermin family proteins. Jiang et al. identified the presence of a conserved gasdermin E homolog in corals that is cleaved by both coral and human caspase-3 to form two active N-terminal isoforms each capable of inducing pyroptosis. After pathogen infection, caspase-dependent gasdermin E activation was associated with mitochondrial disruption and necrosis in the reef-building coral species Pocillopora damicornis. These results demonstrate that gasdermin-mediated cell death is likely conserved in some invertebrates and may represent an immune defense activated in corals during bacterial infection resulting from environmental stress.

Abstract

Gasdermins are executioners of the inflammatory cell death pathway pyroptosis that has so far been studied exclusively in vertebrates. In this study, we identified gasdermin E (GSDME) homologs in several invertebrate species including corals. We report that coral GSDME was cleaved by caspase 3 at two sites, yielding two active isoforms of GSDME N-terminal domain that were capable of inducing pyroptosis. Ectopic coexpression of coral GSDME and caspase 3 in human cells promoted pyroptosis. Corals infected with Vibrio coralliilyticus, a bacterial pathogen causing rapid tissue necrosis of corals worldwide, exhibited necrotic death with elevated caspase 3 activity and GSDME cleavage, whereas inhibition of caspase 3 blocked GSDME cleavage and protected corals from necrotic death. These results indicate that functional gasdermin exists in invertebrates and that coral gasdermin is involved in pathogen-induced coral death. Furthermore, our studies also suggest that mediation of pyroptosis is an evolutionarily conserved function of gasdermins.

View Full Text

Stay Connected to Science Immunology