Fig. 8
From: Sequential trafficking of Env and Gag to HIV-1 T cell virological synapses revealed by live imaging
A two-step model of HIV-1 VS formation. Based on time-lapse fluorescence microscopy, formation of HIV-1 VS following a two-step process. At stage 1, Env accumulation is induced at the site of cell contact between an HIV infected donor cell and an uninfected target CD4 cell. Env on the donor cell interact with CD4 on target cell to stabilize the contact. Other adhesive molecules, e.g. ICAM-1, may also play a role in the formation of stable contact. At stage 2, after a stable contact has been established, Gag redistributes at the contact area to form a “button” like structure