- Kane, Joshua R;
- Stanley, David J;
- Hultquist, Judd F;
- Johnson, Jeffrey R;
- Mietrach, Nicole;
- Binning, Jennifer M;
- Jónsson, Stefán R;
- Barelier, Sarah;
- Newton, Billy W;
- Johnson, Tasha L;
- Franks-Skiba, Kathleen E;
- Li, Ming;
- Brown, William L;
- Gunnarsson, Hörður I;
- Adalbjornsdóttir, Adalbjorg;
- Fraser, James S;
- Harris, Reuben S;
- Andrésdóttir, Valgerður;
- Gross, John D;
- Krogan, Nevan J
HIV-1 encodes the accessory protein Vif, which hijacks a host Cullin-RING ubiquitin ligase (CRL) complex as well as the non-canonical cofactor CBFβ, to antagonize APOBEC3 antiviral proteins. Non-canonical cofactor recruitment to CRL complexes by viral factors, to date, has only been attributed to HIV-1 Vif. To further study this phenomenon, we employed a comparative approach combining proteomic, biochemical, structural, and virological techniques to investigate Vif complexes across the lentivirus genus, including primate (HIV-1 and simian immunodeficiency virus macaque [SIVmac]) and non-primate (FIV, BIV, and MVV) viruses. We find that CBFβ is completely dispensable for the activity of non-primate lentiviral Vif proteins. Furthermore, we find that BIV Vif requires no cofactor and that MVV Vif requires a novel cofactor, cyclophilin A (CYPA), for stable CRL complex formation and anti-APOBEC3 activity. We propose modular conservation of Vif complexes allows for potential exaptation of functions through the acquisition of non-CRL-associated host cofactors while preserving anti-APOBEC3 activity.