A Comparison of Genome Structures in Naturally Occurring Virulent and Avirulent Coxsackiesviruses

Coxsackievirus B3 (CVB3) in an enterovirus in the family Picornaviridae and relevant to human health, causing diseases including myocarditis, pancreatitis and aseptic meningitis. The viral genome includes a 742 nucleotide 5’Untranslated Region (5’UTR) that serves a critical role in CVB3 infection. Efficient viral replication and viral peptide synthesis require a specific 5’UTR secondary structure that has been extensively studied. Two naturally occurring strains of CVB3 include the virulent CVB3/28 and the avirulent CVB3/GA. Previous studies have used chemical probing to characterize the secondary structure of CVB3/28 and generate an experimentally supported structural model. This current study further examines and compares the CVB3 5’UTR secondary structure in both CVB3/GA and CVB3/28. The primary sequence of both strains have been determined in previous reports, and sequence changes occur at 63 of the 742 positions. Given this variability, the CVB3/GA 5’UTR may include mutations that disrupt or alter the formation of the specific secondary structures required for viral processes. Identification of 5’UTR structural differences between naturally occurring virulent CVB3/28 and avirulent CVB3/GA may provide a better understanding of the structures required for CVB3 5’UTR functionality as well as CVB3 virulence