title: Monoclonal antibodies to the P protein of Sendai virus define its structure and role in transcription.
abstract: Four monoclonal antibodies specific for Sendai virus nucleocapsid protein P were used to examine both the antigenic structure of P and its role in transcription. Three distinct antigenic regions were delineated on P by competitive radioimmunoassays (RIAs), and through Western blot analysis all three sites were mapped to a 40,000-MW (40K) Staphylococcus aureus protease V8-digestion fragment, which remains associated with the neucleocapsid structure. To study the function of P, nucleocapsids were treated with saturating amounts of anti-P monoclonal antibodies and it was found that transcription in vitro was inhibited by 60-90%. Data, therefore, are consistent with the conclusion that the P protein is required for transcription and that the 40K protease-resistant core contains the functionally important portion of the molecule. Further analysis of the P structure showed that some of the 40K fragments were linked by disulfide bonds. These results suggest that the protease-resistant 40K fragment is in the carboxyl-terminal half of P, since the three cysteine residues of P are found there (C. Giorgi, B. M. Blumberg, and D. Kolakofsky (1983), Cell 35, 829-836).
authors.forename: K L
authors.initials: KL
authors.lastname: Deshpande
authors.forename: A
authors.initials: A
authors.lastname: Portner
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D000936:Antigen-Antibody Complex; D002478:Cells, Cultured; D002642:Chick Embryo; D000939:Epitopes / Q000032:analysis; D007700:Kinetics; D008168:Lung; D008970:Molecular Weight; D019590:Nucleocapsid Proteins; D009698:Nucleoproteins; D010222:Parainfluenza Virus 1, Human / Q000235:genetics*; D011863:Radioimmunoassay; D014158:Transcription, Genetic; D014758:Viral Core Proteins; D014764:Viral Proteins / Q000235:genetics*
chemical_list: D000911:Antibodies, Monoclonal; D000936:Antigen-Antibody Complex; D000939:Epitopes; D019590:Nucleocapsid Proteins; D009698:Nucleoproteins; D014758:Viral Core Proteins; D014764:Viral Proteins