Virion-associated HIV-1 Vpr: variable amount in virus particles derived from cells upon virus infection or proviral DNA transfection.
Human immunodeficiency virus type-1 (HIV-1) Vpr is a virion-associated protein implicated to have a role in AIDS pathogenesis. In regard to the amount of Vpr incorporated into virus particles, the published data vary widely. To address this, we quantitated Vpr in virus particles derived from diverse sources that are used to evaluate the biological effect of Vpr. Virus particles from infected cells showed only a small amount of Vpr. Interestingly, virus particles from cells cotransfected with HIV-1 proviral DNA lacking Vpr coding sequences (NLDeltaVpr) and a Vpr expression plasmid showed a drastic increase (29.4-fold) in the incorporation of Vpr. Furthermore, cotransfection involving NLDeltaVpr and different concentrations of Vpr expression plasmid resulted in virus particles containing Vpr in proportion to the Vpr expression plasmid used. The differences in virus particles with respect to Vpr as revealed by these studies should be taken into account in assessing the effect of Vpr.
Singh
S P
SP
Department of Microbiology and Immunology, Thomas Jefferson University, 1020 Locust Street, Philadelphia, PA 19107, USA.
Tungaturthi
P
P
Cartas
M
M
Tomkowicz
B
B
Rizvi
T A
TA
Khan
S A
SA
Kalyanaraman
V S
VS
Srinivasan
A
A
D002460:Cell Line; D004279:DNA, Viral / Q000235:genetics; D016336:Gene Products, vpr / Q000235:genetics / Q000378:metabolism*; D015658:HIV Infections / Q000821:virology*; D015497:HIV-1 / Q000235:genetics / Q000502:physiology*; D006801:Humans; D015151:Immunoblotting; D011533:Proviruses / Q000235:genetics; D014162:Transfection; D014771:Virion / Q000378:metabolism*; D054325:vpr Gene Products, Human Immunodeficiency Virus
D004279:DNA, Viral; D016336:Gene Products, vpr; D054325:vpr Gene Products, Human Immunodeficiency Virus