Human immunodeficiency virus type 1: Role of proteins in the context of viral life cycle

The Acquired Immunodeficiency Syndrome (AIDS) is a major global pandemic and of paramount public health concern. Over the years, antiretroviral therapy (ART) has emerged as the gold standard of AIDS treatment. However, drug resistance and toxicity, and drug accessibility and compliance issues have blunted its positive impacts. Thirty years into the AIDS pandemic, there is a critical need of the hour to identify and develop an effective treatment strategy that can be successfully implemented with high levels of coverage. The HIV-1 life cycle bestows numerous potential targets for therapeutic intervention, however, only a few have been exploited till date. HIV- 1 encodes fifteen viral proteins from just nine genes. The expression of structural polyproteins Gag, Pol, and Env enable the assembly of the virion, the regulatory proteins Rev and Tat regulate viral gene expression and the accessory proteins Vpu, Nef, Vpr, and Vif equip the virion to evade or counteract host immune defenses. In this review article, we highlight each structural, regulatory, and accessory protein's role in the context of the HIV-1 life cycle. We also discuss anti-retroviral therapy, its advantages, and shortcomings. Finally, we provide insight into various unexploited and potential therapeutic targets in the life cycle of HIV.