title: Mutational analysis of the influenza virus A/Victoria/3/75 PA protein: studies of interaction with PB1 protein and identification of a dominant negative mutant.
abstract: The RNA polymerase activity and PB1 binding of influenza virus PA mutants were studied using an in vivo-reconstituted polymerase assay and a two hybrid system. Deletions covering the whole PA protein abolished polymerase activity, but the deletion of the 154 N-terminal amino acids allowed PB1 binding, indicating that the PA protein N terminus is not absolutely required for this interaction. Further internal or C-terminal deletions abolished PB1 interaction, suggesting that most of the protein is involved in this association. As a novel finding we showed that a single amino acid insertion mutant, PAI672, was responsible for a temperature-sensitive phenotype. Mutant PAS509, which had a serine insertion at position 509, bound to PB1 like wild-type PA but did not show any polymerase activity. Over-expression of PAS509 interfered with the polymerase activity of wild-type PA, identifying PAS509 as a dominant negative mutant.
authors: Centro Nacional de Biotecnologia (CSIC), Universidad Autonoma, Cantoblanco, Madrid, Spain.
authors: T
authors: T
authors: Zürcher
authors: S
authors: S
authors: de la Luna
authors: J J
authors: JJ
authors: Sanz-Ezquerro
authors: A
authors: A
authors: Nieto
authors: J
authors: J
authors: Ortín
mesh_terms: D000818:Animals; D001665:Binding Sites; D002461:Cell Line, Transformed; D002522:Chlorocebus aethiops; D012321:DNA-Directed RNA Polymerases / Q000235:genetics* / Q000378:metabolism; D005799:Genes, Dominant; D006801:Humans; D009980:Influenza A virus / Q000201:enzymology*; D009154:Mutation; D017384:Sequence Deletion; D014764:Viral Proteins / Q000378:metabolism*
chemical_list: D014764:Viral Proteins; C077346:influenza virus polymerase basic protein 1; D012321:DNA-Directed RNA Polymerases