Requirement of casein kinase II-mediated phosphorylation for the transcriptional activity of human respiratory syncytial viral phosphoprotein P: transdominant negative phenotype of phosphorylation-defective P mutants.
The transcription complex of the human respiratory syncytial virus was biochemically dissected and reconstituted in vitro with purified viral macromolecules. The minimal complex consisted of the viral N-RNA template, viral phosphoprotein (P), and the large protein (L) along with host cellular factor(s), possibly actin. Active transcription could also be reconstituted using bacterially synthesized recombinant P protein provided the P protein was phosphorylated by cellular casein kinase II. Elimination of phosphorylation by inhibition of CKII or by mutation of the Ser residue at position 237 of the P protein also abrogated RSV transcription. In addition, the phosphorylation-defective P mutants exhibited a trans-dominant negative phenotype, consistent with the finding that the mutant proteins bound to the N-RNA template as efficiently as the wild type. Once engaged in transcription, however, the wild-type P protein became refractory to trans-inhibition by the mutant.
Department of Biochemistry and Molecular Biology, College of Medicine, University of South Alabama, Mobile 36688-0002.
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Mazumder
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Barik
D047390:Casein Kinase II; D015707:HN Protein; D006801:Humans; D009154:Mutation; D010641:Phenotype; D010710:Phosphates; D010766:Phosphorylation; D011485:Protein Binding; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D012136:Respiratory Syncytial Viruses / Q000235:genetics / Q000378:metabolism*; D013698:Templates, Genetic; D014158:Transcription, Genetic; D014407:Tumor Cells, Cultured; D014759:Viral Envelope Proteins; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism*
D015707:HN Protein; D010710:Phosphates; D014759:Viral Envelope Proteins; D014764:Viral Proteins; C116204:attachment protein G; D047390:Casein Kinase II; D017346:Protein Serine-Threonine Kinases