Identifying RNA Helicase Inhibitors Using Duplex Unwinding Assays

Hijacking a real time detection thermocycler for enzymology: improvement of a fluorescent bulk assay monitoring helicase activity

Helicases are enzymes involved in all aspects of nucleic acid synthesis, regulation and degradation. As a consequence, several methods were developed to monitor their enzymatic activity. In this report, we described an improvement of bulk fluorescent helicase assays to overcome their specific limitations (cost, health and safety regulations, etc..). Using a real time detection thermocycler to monitor the fluorescence in real-time, we managed to precisely control the initiation of the helicase reaction through temperature tuning. Therefore, we were able to demonstrate that this setup could provide a qualitative and a quantitative evaluation of the helicase domain of the UPF1 helicase (UPF1-HD) and that several fluorophores could be used in parallel during the same run.

RNA helicases required for viral propagation in humans

RNA viruses cause many routine illnesses, such as the common cold and the flu. Recently, more deadly diseases have emerged from this family of viruses. The hepatitis C virus has had a devastating impact worldwide. Despite the cures developed in the U.S. and Europe, economically disadvantaged countries remain afflicted by HCV infection due to the high cost of these medications. More recently, COVID-19 has swept across the world, killing millions and disrupting economies and lifestyles; the virus responsible for this pandemic is a coronavirus. Our understanding of HCV and SARS CoV-2 replication is still in its infancy. Helicases play a critical role in the replication, transcription and translation of viruses. These key enzymes need extensive study not only as an essential player in the viral lifecycle, but also as targets for antiviral therapeutics. In this review, we highlight the current knowledge for RNA helicases of high importance to human health.