Fig. 4D, lane 6) of
cytosolic extract bound the RV RNA. The decrease in
binding of Cal-MBP in the presence of Vero 76 cell lysate
probably reflects competition between phosphorylated Cal-
MBP and endogenous calreticulin in the lysate. In the absence
of prior phosphorylation, Cal-MBP did not exhibit RV
RNA binding activity (Fig. 4D, lane 2). Treatment with
alkaline phosphatase of the phosphorylated protein prior to
its incubation with RV RNA abrogated the binding of Cal-
MBP (Fig. 4D, lane 7). MBP when treated in a similar manner
did not bind to RV RNA (Fig. 4D, lanes 3 and 5).