Picornavirus-receptor interactions.

Many picornaviruses use cell-surface molecules belonging to the immunoglobulin superfamily (IgSF) as their cellular receptors. These molecules usually consist of tandem repeats of between two and five Ig-like domains whose amino-terminal domains (D1) interact with invading viruses, with their carboxy-terminal sections comprising a transmembrane and a short cytoplasmic region. Most rhino- and enteroviruses, belonging to the Picornavirus family, use a canyon-like feature on their surface to attach to cellular receptors. Binding into the canyon destabilizes the virus and thus initiates the uncoating process. By contrast, non-IgSF molecules, when used by picornaviruses as receptors, bind outside the canyon and do not cause viral instability.