ERN1 and infection: In this study we found that enteroviruses (poliovirus type I Mahoney and coxsackievirus B3 Nancy) induce autophosphorylation of protein kinase/endoribonuclease Ire1 in infected HeLa cells at the middle stage of infection, but this does not lead to the accumulation of spliced Xbp1 mRNA, the major product of its RNase activity.