Fig. 1
From: Roles of phosphatidylserine exposed on the viral envelope and cell membrane in HIV-1 replication
Molecular mechanisms of virus attachment mediated by envelope PtdSer. Gas6 and protein S mediate binding of the virus to target cells by bridging envelope PtdSer to TAM receptor tyrosine kinase on target cells. MFG-E8 bridges enveloped virus and target cells by binding to envelope PtdSer and to integrins αVβ3 and/or αVβ5 on target cells. TIM-1, − 3, and − 4, and CD300a are type 1 membrane proteins directly bind envelope PtdSer. Axl/Gas6 and TIM-1 and 4 (indicated in red) can mediate enveloped virus infection more efficiently than other PtdSer-binding molecules. In addition to PtdSer, TIM-1 and CD300a can mediate viral attachment by binding to phosphatidylethanolamine exposed on envelope [57, 86]