Pseudo-atomic Structure of Coxsackievirus A21 Complexed with Its Cellular Receptor, ICAM-1

Abstract

Coxsackievirus A21 (CAV21), like human rhinoviruses (HRVs), is a causative agent of the common cold. CAV21 uses the same cellular receptor, intercellular adhesion molecule-1 (ICAM-1), as does the major group of HRVs. Moreover, unlike HRVs, CAV21 is stable over wide pH range. The CAV21 RNA genome has about 80% amino acid sequence identity to polioviruses (PVs), which utilize CD155 as their receptor. In contrast, CAV21 has only about 50% identity to HRVs. Interaction between the virus and the receptor had been studied by fitting atomic structure into a 26A resolution cryo-EM map. [1] However, the low resolution of the cryo-EM density limited the fitting accuracy and affected the interpretation of the interactions. Furthermore, the structure of CAV21, which had been fitted into the cryo-EM map, was modeled from the homologous structures of poliovirus 1 structure instead of using an X-ray crystallographic determined crystal structure.