HIV-1 integrase (IN) is essential for viral replication and thus is an important therapeutic target. During the early stages of viral replication, a tetramer of HIV-1 IN catalyzes integration of reverse transcribed viral DNA into the host genome. The ordered multimerization of IN in the presence of viral DNA is critical for IN catalytic activity. Cellular cofactor LEDGF/p75 binds to the pre-assembled IN- viral DNA complex and tethers the nucleoprotein complex to active genes, thus ensuring effective integration. Allosteric integrase inhibitors (ALLINIs) are a novel class of integrase inhibitors that bind at the LEDGF/p75 binding site at the IN dimer interface and are capable of triggering aberrant IN multimerization. In addition, HIV-1 virions produced in the presence of ALLINIs display abnormal morphology of the virion cores and are defective for subsequent reverse transcription and integration in target cells. Interestingly, these phenotypes are similar to certain IN mutants, which have been termed class II mutants. Collectively, the studies with ALLINIs and select IN class II mutants suggest that HIV-1 IN plays a key role during late stage HIV-1 replication. However, the underlying mechanism is not clear. The present application will test the following hypothesis: ordered IN multimerization is important for its interaction with viral RNA during the late stage viral replication. Therefore, we propose the following two specific aims.
Aim 1 will explore the significance of HIV-1 IN interactions with RNA for formation of the functional ribonuleoprotein complexes during the late stage viral replication.
Aim 2 will characterize IN mutants that affect IN multimerization and/or IN- LEDGF/p75 binding. Mechanistic and structural details that will emerge from these studies will inform drug discovery efforts to develop improved ALLINIs for their clinical application.
HIV-1 integrase catalytic activity is essential during the early steps of HIV-1 infection and has been exploited as an antiviral target in the treatment of HIV-1 infected patients. In addition, recent studies with developmental compounds, termed allosteric IN inhibitors, have highlighted an essential role of integrase for correctly formed cores during late stage viral replication. The present proposal will investigate the significance of interaction between ordered multimeric forms of IN and RNA for the formation of infectious virions.
|Kessl, Jacques J; Sharma, Amit; Kvaratskhelia, Mamuka (2016) Methods for the Analyses of Inhibitor-Induced Aberrant Multimerization of HIV-1 Integrase. Methods Mol Biol 1354:149-64|
|Feng, Lei; Dharmarajan, Venkatasubramanian; Serrao, Erik et al. (2016) The Competitive Interplay between Allosteric HIV-1 Integrase Inhibitor BI/D and LEDGF/p75 during the Early Stage of HIV-1 Replication Adversely Affects Inhibitor Potency. ACS Chem Biol 11:1313-21|
|Patel, Pratiq A; Kvaratskhelia, Nina; Mansour, Yara et al. (2016) Indole-based allosteric inhibitors of HIV-1 integrase. Bioorg Med Chem Lett 26:4748-4752|
|Kessl, Jacques J; Kutluay, Sebla B; Townsend, Dana et al. (2016) HIV-1 Integrase Binds the Viral RNA Genome and Is Essential during Virion Morphogenesis. Cell 166:1257-1268.e12|
|Patel, Disha; Antwi, Janet; Koneru, Pratibha C et al. (2016) A New Class of Allosteric HIV-1 Integrase Inhibitors Identified by Crystallographic Fragment Screening of the Catalytic Core Domain. J Biol Chem 291:23569-23577|
|Feng, Lei; Larue, Ross C; Slaughter, Alison et al. (2015) HIV-1 integrase multimerization as a therapeutic target. Curr Top Microbiol Immunol 389:93-119|
|Shkriabai, Nikoloz; Dharmarajan, Venkatasubramanian; Slaughter, Alison et al. (2014) A critical role of the C-terminal segment for allosteric inhibitor-induced aberrant multimerization of HIV-1 integrase. J Biol Chem 289:26430-40|
|Slaughter, Alison; Jurado, Kellie A; Deng, Nanjie et al. (2014) The mechanism of H171T resistance reveals the importance of N?-protonated His171 for the binding of allosteric inhibitor BI-D to HIV-1 integrase. Retrovirology 11:100|
|Sharma, Amit; Slaughter, Alison; Jena, Nivedita et al. (2014) A new class of multimerization selective inhibitors of HIV-1 integrase. PLoS Pathog 10:e1004171|