XPO1 and viral infectious disease: Of the known exportins, CRM1 is an essential and most often used exportin in cells, which exports numerous cargoes including both proteins and RNAs.1,34–36 More than 1050 cargoes have been identified in human cells through proteomic approaches, among which >200 cargoes have been verified through different techniques.37–40 CRM1-mediated nuclear export is implicated in various diseases, including cancer, wound healing, inflammation and viral infection.