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Annotation rule MF_04081
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General rule information [?]

Accession MF_04081
Dates 1-JUN-2017 (Created)
20-NOV-2019 (Last updated, Version 5)
Viruses; Lentivirus
Template P69723 (VIF_HV1H2)

Propagated annotation [?]

Identifier, protein and gene names [?]

Protein name
RecName: Full=Virion infectivity factor;
AltName: Full=SOR protein;
RecName: Full=p17;
RecName: Full=p7;
Gene name

Comments [?]

Function Counteracts the innate antiviral activity of host APOBEC3F and APOBEC3G. Forms a complex with host APOBEC3F and APOBEC3G thus preventing the entry of these lethally hypermutating enzymes into progeny virions. Recruits an active E3 ubiquitin ligase complex composed of elongin BC, CUL5, and RBX2 to induce polyubiquitination of APOBEC3G and APOBEC3F. In turn, they are directed to the 26S proteasome for degradation. Vif interaction with APOBEC3G also blocks its cytidine deaminase activity in a proteasome-independent manner, suggesting a dual inhibitory mechanism. May interact directly with APOBEC3G mRNA in order to inhibit its translation. Seems to play a role in viral morphology by affecting the stability of the viral nucleoprotein core. Finally, Vif also contributes to the G2 cell cycle arrest observed in HIV infected cells.
Subunit Homomultimer; in vitro and presumably in vivo. Interacts with viral RNA and Pr55Gag precursor; these interactions mediate Vif incorporation into the virion. Interacts with the viral reverse transcriptase. Interacts with human APOBEC3F and APOBEC3G. Interacts with host UBCE7IP1 isoform 3/ZIN and possibly with SAT. Interacts with host tyrosine kinases HCK and FYN; these interactions may decrease level of phosphorylated APOBEC3G incorporation into virions. Interacts with host ABCE1; this interaction may play a role in protecting viral RNA from damage during viral assembly. Forms an E3 ligase complex by interacting with host CUL5 and elongin BC complex (ELOB and ELOC). Interacts with host MDM2; this interaction targets Vif for degradation by the proteasome.
Subcellular location Host cytoplasm. Host cell membrane; Peripheral membrane protein; Cytoplasmic side. Virion. Note=In the cytoplasm, seems to colocalize with intermediate filament vimentin. A fraction is associated with the cytoplasmic side of cellular membranes, presumably via the interaction with Pr55Gag precursor. Incorporated in virions at a ratio of approximately 7 to 20 molecules per virion.
Induction Expressed late during infection in a Rev-dependent manner.
Domain The BC-like-box motif mediates the interaction with elongin BC complex.
The HCCH motif (H-x(5)-C-x(18)-C-x(5)-H) mediates the interaction with CUL5.
Ptm Processed in virion by the viral protease.
Highly phosphorylated on serine and threonine residues.
Polyubiquitinated and degraded by the proteasome in the presence of APOBEC3G.
Miscellaneous Required for replication in 'nonpermissive' cells, including primary T-cells, macrophages and certain T-cell lines, but is dispensable for replication in 'permissive' cell lines, such as 293T cells. In nonpermissive cells, Vif-defective viruses can produce virions, but they fail to complete reverse transcription and cannot successfully infect new cells.
Vif-defective viruses show catastrophic failure in reverse transcription due to APOBEC-induced mutations that initiate a DNA base repair pathway and compromise the structural integrity of the ssDNA. In the absence of Vif, the virion is morphologically abnormal.
HIV-1 lineages are divided in three main groups, M (for Major), O (for Outlier), and N (for New, or Non-M, Non-O). The vast majority of strains found worldwide belong to the group M. Group O seems to be endemic to and largely confined to Cameroon and neighboring countries in West Central Africa, where these viruses represent a small minority of HIV-1 strains. The group N is represented by a limited number of isolates from Cameroonian persons. The group M is further subdivided in 9 clades or subtypes (A to D, F to H, J and K).
Similarity Belongs to the primate lentivirus group Vif protein family.

Keywords [?]

Gene Ontology [?]

GO:0030430; Cellular component: host cell cytoplasm.
GO:0020002; Cellular component: host cell plasma membrane.
GO:0016020; Cellular component: membrane.
GO:0005654; Cellular component: nucleoplasm.
GO:0019012; Cellular component: virion.
GO:0003723; Molecular function: RNA binding.

Cross-references [?]

Pfam PF00559; Vif; 1;

Features [?]

From: VIF_HV1H2 (P69723)
Key     From     To       Description   Tag   Condition   FTGroup
CHAIN     Nter     Cter       Virion infectivity factor        
CHAIN     1     150       p17        
CHAIN     151     192       p7        
REGION     14     17       Interaction with host APOBEC3F; F1-box        
REGION     40     44       Interaction with host APOBEC3G; G-box        
REGION     54     72       Interaction with host APOBEC3F and APOBEC3G; FG-box        
REGION     74     79       Interaction with host APOBEC3F; F2-box        
REGION     75     114       RNA-binding        
REGION     151     164       Multimerization        
REGION     171     172       Membrane association     E-D  
MOTIF     108     139       HCCH motif        
MOTIF     144     153       BC-box-like motif        
SITE     150     151       Cleavage in virion (by viral protease)        
MOD_RES     96     96       Phosphothreonine; by host MAP4K1     T  
MOD_RES     144     144       Phosphoserine; by host     S  
MOD_RES     155     155       Phosphothreonine; by host     T  
MOD_RES     165     165       Phosphoserine; by host MAP4K1     S  
MOD_RES     188     188       Phosphothreonine; by host     T  

Additional information [?]

Size range 188-193 amino acids
Related rules None
Fusion None