Brad Stanley

From WikidChem

Brad Stanley--5th Year MB&B, Laboratory of Yong Xiong

Upon viral infection, the human anti-retroviral protein APOBEC3G mutates reverse transcripts by cytidine deamination. Recent work has demonstrated that APOBEC3G may also physically block reverse transcription by binding viral RNA. While this defense mechanism is effective against some viruses, HIV has evolved a mechanism to evade it. HIV virion infectivity factor (Vif) is essential for HIV to successfully evade the host immune defense. Vif functions as a substrate receptor molecule which binds to APOBEC3G and then recruits the host’s own ubiquitin ligase machinery to target it for destruction by the proteasome. To gain a better understanding of how Vif interacts with host ubiquination machinery and ultimately circumvents APOBEC3G mediated deamination of minus strand DNA, we are working to form complexes between HIV Vif, ElonginB, ElonginC, and Cullin5. We have successfully coexpressed and purified several Vif constructs in complex with ubiquitin ligase components and we are currently working to determine their structures by X-ray crystallography.