Polyubiquitination of APOBEC3G is essential for its degradation by HIV-1 Vif.
Proteasomal degradation of APOBEC3G is a critical step for human immunodeficiency virus type 1 (HIV-1) replication. However, the necessity for polyubiquitination of APOBEC3G in this process is still controversial. In this study, we showed that although macaque simian immunodeficiency virus (SIVmac) Vif is more stable than HIV-1 Vif in human cells, SIVmac Vif induces degradation of APBOEC3G as efficiently as HIV-1 Vif. Overexpression of APOBEC3G or lysine-free APOBEC3G stabilized HIV-1 Vif, indicating that APOBEC3G degradation is independent of the degradation of Vif. Furthermore, an in vivo polyubiquitination assay showed that lysine-free APOBEC3G was also polyubiquitinated. These data suggest that polyubiquitination of APOBEC3G, not that of HIV-1 Vif, is crucial for APOBEC3G degradation.
Center for AIDS Health Disparities Research, School of Medicine, Meharry Medical College, Nashville, Tennessee 37208, USA.
Qiujia
Q
Shao
Yudi
Y
Wang
James E K
JE
Hildreth
Bindong
B
Liu
D000071480:APOBEC-3G Deaminase; D002460:Cell Line; D003564:Cytidine Deaminase / Q000378:metabolism*; D015497:HIV-1 / Q000276:immunology / Q000472:pathogenicity*; D006801:Humans; D015302:Simian Immunodeficiency Virus / Q000276:immunology / Q000472:pathogenicity; D054875:Ubiquitination; D054320:vif Gene Products, Human Immunodeficiency Virus / Q000378:metabolism*
D054320:vif Gene Products, Human Immunodeficiency Virus; C514847:vif protein, Human immunodeficiency virus 1; D000071480:APOBEC-3G Deaminase; C464924:APOBEC3G protein, human; D003564:Cytidine Deaminase