Upregulation of survivin by HIV-1 Vpr

The human survivin gene belongs to the family of inhibitor of apoptosis proteins (IAP) and is involved in apoptosis inhibition and regulation of cell division. The survivin gene is the only member of the IAP family whose expression is known to be regulated through the cell cycle. Survivin expression reaches the highest levels during the G2/M transition and then is rapidly degraded during the G1 phase. Here we report that the human immunodeficiency virus type 1 (HIV-1) upregulates Survivin expression via survivin promoter transactivation. Vpr, an HIV-1 accessory protein that induces cell cycle arrest in G2/M, is necessary and sufficient for this effect. Blocking Vpr-induced G2/M arrest leads to elimination of the survivin promoter transactivation by Vpr. Our results suggest that Survivin may be actively involved in regulating cell viability during HIV-1 infection.