Robert J. Geraghty, PhD
Program Director for Biology
Genetics and Cell Biology, University of Minnesota, Minneapolis, MN (1988)
Oncology, University of Wisconsin, WI (1995)
Anti-Viral Drug Discovery:
Our main interests are identifying anti-viral drug targets for major human pathogens and evaluating small molecules for their ability to inhibit those targets and virus replication.
We employ three main approaches to uncover small molecules that inhibit the replication and pathogenesis of viruses: (1) Conduct phenotypic screens to evaluate anti-viral activity of small molecules. (2) Collaborate with medicinal chemists, computational chemists and structural biologists to rationally design small molecule inhibitors of established and novel viral drug targets. (3) Design and implement high throughput screening to identify small molecules that inhibit known and novel viral drug targets.
Investigation of Aspects of Virus Replication:
We are investigating aspects of virus replication for the following viruses - For the Flaviviruses hepatitis C virus and West Nile virus as well as the Orthomyxovirus influenza A virus, we have active projects to identify inhibitors of the respective viral polymerases. We are also interested in identifying inhibitors of cellular factors that those viruses must use to replicate.
We are currently studying two Herpesviruses, herpes simplex virus (HSV) and cytomegalovirus (CMV). We have a long-standing interest in understanding the molecular details of HSV entry into cells. We are interested in the entire process of virus entry including binding to cells, fusion of the viral membrane with cell membranes either at the plasma membrane or in an endocytic vesicle, and the role of pH in the entry/fusion process. We continue to study the expression of the major viral surface proteins, their incorporation onto virus particles, and their roles in cell binding and membrane fusion. The ultimate goal of these studies is to identify steps in virus entry that are most susceptible to inhibition using small molecules such as organic compounds or small proteins/peptides. The beta herpesvirus CMV is a major pathogen for neonates and the immune compromised. We are taking a target-based approach to interrogate viral enzymes with known and novel chemotypes to identify inhibitors. The viral enzyme inhibitors identified are then screened for their ability to inhibit virus replication in cell culture.
We have collaborative projects looking at novel targets and anti-virals for human immunodeficiency virus and also to understand the entry of coronaviruses into cells.
Identification of Antiviral Inhibitors for:
- Hepatitis C Virus
- West Nile Virus
- Influenza A Virus
- Human Immunodeficiency Virus
Recent Publications (For detailed publication list: Click Here)
Zhou, W., Duckworth, B. P.; Geraghty, R. J. Fluorescent peptide sensors for tyrosylprotein sulfotransferase activity. Anal. Biochem. 2014, 461, 1-6.
Vernekar, S. K. V.; Qiu, L.; Zacharias, J.; Geraghty, R. J.; Wang, Z. Synthesis and antiviral evaluation of 4’-(1,2,3-triazol-1-yl)thymidines. Med. Chem. Commun. 2014, 5, 603-608.
Zhou, W.; Chen, F.; Klyachkin, Y.; Sham, Y. Y.; Geraghty, R. J.; Mutations in the amino terminus of herpes simplex virus type 1 gL can reduce cell-cell fusion without affecting gH/gL trafficking. J. Virol. 2013, 88, 739-744.
Wu, K.; Peng, G.; Wilken, M.; Geraghty, R. J.; Li, F. Mechanisms of host receptor adaptation by severe acute respiratory syndrome coronavirus. J. Biol. Chem. 2012, 287, 8904-8911.
Chen, Y.-L.; Zacharias, J.; Vince, R.; Geraghty, R. J.; Wang, Z. C-6 Aryl substituted 4-quinolone-3-carboxylic acids as inhibitors of hepatitis C virus. Bioorg. Med. Chem. 2012, 20, 4790-4800.
Chen, Y.-L.; Tang, J.; Kesler, M. J.; Sham, Y. Y.; Vince, R.; Geraghty, R. J.; Wang, Z. The design, synthesis and biological evaluations of C-6 or C-7 substituted 2-hydroxyisoquinoline-1,3-diones as inhibitors of hepatitis C virus. Bioorg. Med. Chem. 2012, 20, 467-479.
Wu, K.; Chen, L.; Peng, G.; Zhou, W.; Pennell, C. A.; Mansky, L. M.; Geraghty, R. J.; Li, F. A virus-binding hot spot on human angiotensin-converting enzyme 2 is critical for binding of two different coronaviruses. J. Virol. 2011, 85, 5331-5337.
Klyachkin, Y. M.; Geraghty, R. J. Mutagenic analysis of herpes simplex virus type 1 glycoprotein L reveals the importance of an arginine-rich region for function. Virology 2008, 374, 23-32.
Subramanian, R. P.; Geraghty, R. J. Herpes simplex virus type 1 mediates fusion through a hemifusion intermediate by sequential activity of glycoproteins D, H, L, and B. Proc. Natl. Acad. Sci. U. S. A. 2007, 104, 2903-2908.
Klyachkin, Y. M.; Stoops, K. D.; Geraghty, R. J. Herpes simplex virus type 1 glycoprotein L mutants that fail to promote trafficking of glycoprotein H and fail to function in fusion can induce binding of glycoprotein L-dependent anti-glycoprotein H antibodies. J. Gen. Virol. 2006, 87, 759-767.