Stratégies de formation de la structure coiffe chez les virus à ARN

Most viruses use the mRNA-cap dependent cellular translation machinery to translate their mRNAs into proteins. The addition of a structure at the 5' end of mRNA is therefore an essential step for the replication of many virus families. Additionally, the protects the viral RNA from degradation by cellular nucleases and prevents viral RNA recognition by innate immunity mechanisms. Viral RNAs acquire their structure either by using cellular capping enzymes, by stealing the of cellular mRNA in a process named cap snatching, or using virus-encoded capping enzymes. Many viral enzymes involved in this process have recently been structurally and functionally characterized. These studies have revealed original synthesis mechanisms and pave the way towards the development of specific inhibitors bearing antiviral drug potential.