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Wong RW, Balachandran A, Cheung PK, Cheng R, Pan Q, Stoilov P, Harrigan PR, Blencowe BJ, Branch DR, Cochrane A. An activator of G protein-coupled receptor and MEK1/2-ERK1/2 signaling inhibits HIV-1 replication by altering viral RNA processing. PLoS Pathog 2020; 16:e1008307. [PMID: 32069328 PMCID: PMC7048317 DOI: 10.1371/journal.ppat.1008307] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 02/28/2020] [Accepted: 01/06/2020] [Indexed: 12/17/2022] Open
Abstract
The ability of HIV-1 to evolve resistance to combined antiretroviral therapies (cARTs) has stimulated research into alternative means of controlling this infection. We assayed >60 modulators of RNA alternative splicing (AS) to identify new inhibitors of HIV-1 RNA processing-a segment of the viral lifecycle not targeted by current drugs-and discovered compound N-[4-chloro-3-(trifluoromethyl)phenyl]-7-nitro-2,1,3-benzoxadiazol-4-amine (5342191) as a potent inhibitor of both wild-type (Ba-L, NL4-3, LAI, IIIB, and N54) and drug-resistant strains of HIV-1 (IC50: ~700 nM) with no significant effect on cell viability at doses tested. 5342191 blocks expression of four essential HIV-1 structural and regulatory proteins (Gag, Env, Tat, and Rev) without affecting total protein synthesis of the cell. This response is associated with altered unspliced (US) and singly-spliced (SS) HIV-1 RNA accumulation (~60% reduction) and transport to the cytoplasm (loss of Rev) whereas parallel analysis of cellular RNAs revealed less than a 0.7% of host alternative splicing (AS) events (0.25-0.67% by ≥ 10-20%), gene expression (0.01-0.46% by ≥ 2-5 fold), and protein abundance (0.02-0.34% by ≥ 1.5-2 fold) being affected. Decreased expression of Tat, but not Gag/Env, upon 5342191 treatment was reversed by a proteasome inhibitor, suggesting that this compound alters the synthesis/degradation of this key viral factor. Consistent with an affect on HIV-1 RNA processing, 5342191 treatment of cells altered the abundance and phosphorylation of serine/arginine-rich splicing factor (SRSF) 1, 3, and 4. Despite the activation of several intracellular signaling pathways by 5342191 (Ras, MEK1/2-ERK1/2, and JNK1/2/3), inhibition of HIV-1 gene expression by this compound could be reversed by pre-treatment with either a G-protein α-subunit inhibitor or two different MEK1/2 inhibitors. These observations demonstrate enhanced sensitivity of HIV-1 gene expression to small changes in host RNA processing and highlights the potential of modulating host intracellular signaling as an alternative approach for controlling HIV-1 infection.
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Affiliation(s)
- Raymond W. Wong
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Ahalya Balachandran
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Peter K. Cheung
- British Columbia Centre for Excellence in HIV/AIDS, Vancouver, British Columbia, Canada
| | - Ran Cheng
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Qun Pan
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario, Canada
| | - Peter Stoilov
- Department of Biochemistry, West Virginia University, Morgantown, West Virginia, United States of America
| | - P. Richard Harrigan
- British Columbia Centre for Excellence in HIV/AIDS, Vancouver, British Columbia, Canada
- Department of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Benjamin J. Blencowe
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario, Canada
| | - Donald R. Branch
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
- Division of Advanced Diagnostics, Infection and Immunity Group, Toronto General Hospital Research Institute, Toronto, Ontario, Canada
- Centre for Innovation, Canadian Blood Services, Toronto, Ontario, Canada
| | - Alan Cochrane
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
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Branch DR. Role of G protein-coupled vasoactive intestinal peptide receptors in HIV integration. Future Virol 2011. [DOI: 10.2217/fvl.11.42] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The pathogenesis of HIV infection is closely linked to the replication of the virus in vivo. Even though the progress in anti-HIV-1 chemotherapy in the past several years has been dramatic, the efficient protection against HIV-1 infection still remains one of the most important global challenges. The complete blockage of AIDS progression appears to be difficult with current treatment due to the rapid occurrence of viral drug-resistance, increasing cost and the likelihood of adverse side effects. Furthermore, although originally regarded with high hope, development of a suitable vaccine appears to be years away. The purpose of this article is to describe previous findings regarding a potentially important role of the vasoactive intestinal peptide/pituitary adenylate cyclase-activating polypeptide (VPAC) family of G protein-coupled receptors in HIV-1 infection, to provide evidence for the involvement of these receptors in providing signals that can control the integration of the virus into the host DNA and to report new findings that support a role for VPAC receptors in the facilitation of HIV integration.
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Affiliation(s)
- Donald R Branch
- Research & Development, Canadian Blood Services, Immunology Hub, Toronto Centre, Toronto, Ontario M5G 2M1, Canada
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