UC San Diego

Cryoelectron microscopy has been used to determine the structure of a virus when complexed with its glycoprotein cellular receptor. Human rhinovirus 16 complexed with the two amino-terminal, immunoglobulin-like domains of the intercellular adhesion molecule 1 shows that the intercellular adhesion molecule 1 binds into the 12-A deep "canyon" on the viral surface. This result confirms the prediction that the viral-receptor attachment site lies in a cavity inaccessible to the host's antibodies. The atomic structures of human rhinovirus 14 and CD4, homologous to human rhinovirus 16 and intercellular adhesion molecule 1, showed excellent correspondence with observed density, thus establishing the virus-receptor interactions.