Discovery of archaeal fusexins homologous to eukaryotic HAP2/GCS1 gamete fusion proteins

Abstract

Sexual reproduction in eukaryotes involves gamete fusion, mediated by fusogenic proteins. Here, the authors identify fusogenic protein homologs encoded within mobile genetic elements in archaeal genomes, solve the crystal structure of one of the proteins, and show that its ectopic expression can fuse mammalian cells, suggesting potential roles in cell-cell fusion and gene exchange.