Syncytin-A (Syna)

This endogenous retroviral envelope protein has retained its original fusogenic properties (PubMed:15644441, PubMed:17762178, PubMed:18077339, PubMed:19564597, PubMed:27589388). Together with Synb, participates in trophoblast fusion and the formation of a syncytium through placenta morphogenesis (PubMed:19564597).

Syna is vital for placental development and is especially required for formation of syncytiotrophoblast layer I (SynT-I) (PubMed:19564597). Promotes muscle myoblast fusion (PubMed:27589388).