Structure-functional analysis of human immunodeficiency virus type 1 (HIV-1) Vpr: role of leucine residues on Vpr-mediated transactivation and virus replication.

HIV-1 Vpr has been shown to transactivate LTR-directed expression through its interaction with several proteins of cellular origin including the glucocorticoid receptor (GR). Upon activation, steroid receptors bind to proteins containing the signature motif LxxLL, translocate into the nucleus, bind to their response element, and activate transcription. The presence of such motifs in HIV-1 Vpr has prompted us to undertake the analysis of the role of specific leucine residue(s) involved in Vpr-GR interaction, subcellular localization and its effect on Vpr-GR-mediated transactivation.

Differential regulation of host cellular genes by HIV-1 viral protein R (Vpr): cDNA microarray analysis using isogenic virus.

HIV-1 Vpr is a protein with multiple functions. It has been suggested that such pleiotropic effects by a viral protein may be mediated by its association with viral and cellular proteins or through modulation of expression of specific cellular genes. To address this, we used cDNA microarray techniques to analyze the regulation of a panel of host cellular genes by HIV-1 Vpr using isogenic HIV-1 either with or without Vpr expression.