Enhanced replication of mouse adenovirus type 1 following virus-induced degradation of protein kinase R (PKR)

Danielle E. Goodman; Carla D. Pretto; Tomas A. Krepostman; Kelly E. Carnahan; Katherine R. Spindler

To determine whether kinase activity of PKR is important for the depletion, we assayed 153 infection of MEFs expressing a mutant form of mouse PKR with a point mutation in the kinase 154 domain (K271R) (55). These cells, designated K271R SV40-MEFs, showed an even more rapid 155 depletion of PKR than in WT SV40-MEFs (Fig. 2C) . At 24 hpi, in K271R SV40-MEFs, 28% of 156 PKR remained, compared to 60% in the WT SV40-MEFs. The fraction remaining at 72 hpi in K271R SV40-MEFs suggests that the upper band of the PKR doublet usually seen in wild-type 161 cells is a phospho-PKR band, because only the lower band of the PKR doublet is seen in kinase-162 dead mutant K271R SV40-MEFs. The data in Fig. 2A and C thus indicate that both PKR and 163 phospho-PKR are depleted during MAV-1 infection. 164