Mapping of monoclonal antibodies to the Sendai virus P protein and the location of its phosphates.

The epitopes of a panel of five monoclonal antibodies to the Sendai virus P protein were mapped by generating modified forms of the P mRNA via SP6 expression followed by in vitro translation. The epitopes were found to be clustered in the C-terminal region of the protein. Two epitopes were within the last 30 residues, two were within the next 65, and one was between residues 308 and 451 of this 568-residue-long protein. By a combination of partial proteolysis and Western immunoblotting with one of these antibodies, the sites at which phosphates are added in vitro by the virion-associated kinase were mapped to the second quarter of the molecule from the N terminus.