In conclusion, the increased accumulation of total viral DNA a few hours after infection with particles produced by Dlg1- cells, together with the increased cholesterol content of these particles and the fact that viral cholesterol content has been reported to determine fusion capacity of HIV-1 [41], are good indications that the effect of Dlg1 on HIV-1 infectivity is probably at the step of virus-cell fusion. This evidence concerns the gene DLG1 and infection.