Fig. 2
From: Roles of phosphatidylserine exposed on the viral envelope and cell membrane in HIV-1 replication
Molecular mechanism of envelope PtdSer-supported HIV-1 binding and entry. HIV-1 infection supported by envelope PtdSer. The interaction between envelope PtdSer and the host’s PtdSer-binding molecules can facilitate HIV-1 binding to target cells. The interaction of the HIV-1 envelope protein with CD4 and co-receptors (CXCR4/CCR5) is still necessary for fusion between the viral envelope and the target cell membrane