[Enhanced protein production of Vif and APOBEC3G by HIV-1 Vpr].
OBJECTIVE
Goal of this study was to test the potential regulatory effects of Vpr on Vif and Vif-mediated degradation of APOBEC3G.


METHODS
The Vpr effect was first tested in a fission yeast RE007 strain that carries a single integrated copy of vpr gene in the chromosome and transformed with a vif-expressing plasmid. Similar tests were also carried out in a muristerone A vpr-inducing HEK293 mammalian cell line that were transfected with the plasmids expressing vif and/or APOBEC3G. Western Blot analyses were used to measure the corresponding protein levels under different experimental conditions.


RESULTS
Expression of HIV-1 vpr appears to enhance the protein levels of Vif both in fission yeast and mammalian cells. A similar enhancement effect of APOBEC3G by Vpr was also detected in mammalian cells. Interestingly, however, the increased Vif protein level by Vpr did not result in more APOBEC3G degradation than without Vpr, indicating a potential regulatory effect of Vpr on Vif-mediated proteolysis of APOBEC3G.


CONCLUSIONS
To our knowledge, this is the first report describing a potentially conserved and regulatory effect of HIV-1 Vpr on Vif and Vif-mediated protein degradation of APOBEC3G.
Li
Lin
L
Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences, Beijing 100071, China. rzhao@som.umaryland.edu
Liang
Dong
D
Li
Jing-yun
JY
Zhao
Yu-qi
YQ
D000071480:APOBEC-3G Deaminase; D000818:Animals; D002460:Cell Line; D003564:Cytidine Deaminase / Q000096:biosynthesis* / Q000378:metabolism; D015870:Gene Expression; D016346:Gene Products, vif / Q000096:biosynthesis* / Q000378:metabolism; D016336:Gene Products, vpr / Q000378:metabolism*; D015497:HIV-1; D006801:Humans; D012568:Schizosaccharomyces / Q000235:genetics
D016346:Gene Products, vif; D016336:Gene Products, vpr; D000071480:APOBEC-3G Deaminase; C464924:APOBEC3G protein, human; D003564:Cytidine Deaminase