{"doi":"10.1111/tra.12389","title":"Fusion of Enveloped Viruses in Endosomes","abstract":"<jats:p>Ari Helenius launched the field of enveloped virus fusion in endosomes with a seminal paper in the <jats:italic>Journal of Cell Biology</jats:italic> in 1980. In the intervening years, a great deal has been learned about the structures and mechanisms of viral membrane fusion proteins as well as about the endosomes in which different enveloped viruses fuse and the endosomal cues that trigger fusion. We now recognize three classes of viral membrane fusion proteins based on structural criteria and four mechanisms of fusion triggering. After reviewing general features of viral membrane fusion proteins and viral fusion in endosomes, we delve into three characterized mechanisms for viral fusion triggering in endosomes: by low <jats:styled-content style=\"fixed-case\">pH</jats:styled-content>, by receptor binding plus low <jats:styled-content style=\"fixed-case\">pH</jats:styled-content> and by receptor binding plus the action of a protease. We end with a discussion of viruses that may employ novel endosomal fusion‐triggering mechanisms. A key take‐home message is that enveloped viruses that enter cells by fusing in endosomes traverse the endocytic pathway until they reach an endosome that has all of the environmental conditions (<jats:styled-content style=\"fixed-case\">pH</jats:styled-content>, proteases, ions, intracellular receptors and lipid composition) to (if needed) prime and (in all cases) trigger the fusion protein and to support membrane fusion.</jats:p><jats:p><jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" xlink:href=\"graphic/tra12389-gra-0001.png\" xlink:title=\"image\"/></jats:p>","journal":"Traffic","year":2016,"id":19715,"datarank":8.984509557203983,"base_score":6.021023349349527,"endowment":6.021023349349527,"self_citation_contribution":0.9031535024024291,"citation_network_contribution":8.081356054801555,"self_endowment_contribution":0.9031535024024291,"citer_contribution":8.081356054801555,"corpus_percentile":null,"corpus_rank":null,"citation_count":411,"citer_count":200,"citers_with_citation_signal":200,"citers_with_endowment":200,"datacite_reuse_total":2,"is_dataset":false,"is_dataset_confidence":null,"is_oa":false,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":107997,"name":"Gary R. 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