IMB-2613

In 2014, two novel and promising benzimidazole-based APOBEC3G stabilizers MM-1 and MM-2 (MMs) were uncovered with an elusive mechanism of action. Vif-APOBEC3G axis has been recognized as a novel therapeutic target for anti HIV-1 drug development. The unexplored mechanism of MMs hindered their further development into lead compounds. To recognize their underlying mechanism we adopted an exhaustive in silico workflow by which we tested their ability to interrupt Vif complex network formation. The preliminary outcome guided us to a high likelihood of MMs interaction within Elongin C binding site, which in turn, perturbs Vif/Elongin C binding and ultimately undermines Vif action. To validate our estimation, we synthesized only MM-1 as a model to complement our study by in vitro assay for a real-time understanding. An immunoprecipitation experiment confirmed the capacity of MM-1 to interrupt Vif/Elongin C interaction. This is an integral study that lies at the interface between theoretical and experimental approaches showing the potential of molecular modelling to address issues related to drug development.

While mutation is the driving force behind evolution, most mutations are detrimental; therefore, elevating the mutation rate of a virus should diminish fitness. Because riboviruses and retroviruses have high mutation rates, a small increase in their mutation rates could exceed their threshold of viability. This approach, elevation of the viral mutation rate beyond the threshold of viability, extinction catastrophe or lethal mutagenesis, was proposed over a decade ago as a novel chemotherapeutic strategy. Extinction catastrophe induced by promutagenic nucleosides has been demonstrated in cell culture models, but most mutagens are carcinogenic and are poorly tolerated. Thus, clinical translation of viral mutagens has been difficult, casting doubt on the clinical viability of this strategy. This Perspective covers recent advances in the use of promutagenic nucleosides and the Vif-APOBEC interaction as chemotherapeutic strategies for targeting viral mutation rates.