Viral RNA-dependent RNA polymerase
The RNA-dependent RNA polymerase (RdRp) drives viral evolution by mediating both genetic drift (mutation) and genetic/antigenic shift (recombination) of RNA viruses. RdRp speed and fidelity contribute to the rate of mutation and formation of the mutant swarm, a well-established determinant of viral fitness and pathogenesis. For more than two decades, we have used the RdRp from poliovirus (PV) as a model system to elucidate fundamental biochemical and biophysical principles governing speed and fidelity of nucleotide addition. Read more…
Picornavirus Genome Replication
Studies of poliovirus (PV) continue to establish paradigms for the molecular and cellular biology of all positive-strand RNA viruses capable of causing morbidity and/or mortality in humans. PV replicates its genome in association with membranes. In fact, the virus creates its own genome-replication organelle (RO) with a unique lipid composition, including an abundance of the phosphoinositide (PIP), phosphatidylinositol-4-phosphate (PI4P). During the past five years, many laboratories have been in search of the mechanism by which PI4P biosynthesis is induced by various picornaviruses, including PV. Read more…
Coronavirus Genome Replication
The world is currently in the midst of a global pandemic caused by the second severe acute respiratory syndrome coronavirus (SARS2). In spite of the foreshadowing of such a pandemic by the emergence of SARS1 in 2002 and Middle East respiratory syndrome coronavirus (MERS) in 2012, we were ill equipped to address this scourge. Each of these early outbreaks yielded a substantial body of knowledge on the structures of coronavirus proteins. As with previous outbreaks, we are witnessing a redoubled coronavirus research effort. Structural biology continues to lead the way; however, our laboratory is now pledging a sustained commitment to elucidation of the fundamental enzymology and corresponding mechanisms of coronavirus genome replication. Read more…
Single-cell Virology
Viral infection poses a never-ending threat to human health. Readiness for a viral epidemic of unknown etiology requires broad-spectrum antiviral therapeutics and universal strategies for viral attenuation. Our laboratory has had a longstanding interest in the discovery of knowledge to enable development of approaches to treat and/or to prevent viral infection. Read more…
Enteroviral 2C Protein as an Antiviral Target
The enteroviral genome encodes a polyprotein, which is divided into three functional regions: P1, P2, and P3. The P2 region is comprised of three protein domains: 2A, 2B, and 2C. For decades, 2C protein has been a validated target for anti-enteroviral therapeutics. Guanidine inhibits PV genome replication, and resistance maps to 2C-coding sequence. A hydantoin-containing compound inhibits infection by PV at a stage of the lifecycle after genome replication, perhaps encapsidation, and resistance again maps to 2C-coding sequence. More recently, screens to discover anti-enteroviral compounds have identified even more compounds targeting 2C protein, based on the genetics of resistance. However, essentially nothing is known about the biochemical/biophysical mechanism(s) of action of these compounds. Read more…
