title: The Sendai virus V protein interacts with the NP protein to regulate viral genome RNA replication.
abstract: The interactions of Sendai virus proteins required for viral RNA synthesis have been characterized both by the yeast two-hybrid system and through the use of glutathione S-transferase (gst)-viral fusion proteins synthesized in mammalian cells. Using the two-hybrid system we have confirmed the previously identified P-L (RNA polymerase), NPo-P (encapsidation substrate), and P-P complexes and now demonstrate NP-NP and NPo-V protein interactions. Expression of gstP and P proteins and binding to glutathione-Sepharose beads as a measure of complex formation confirmed the P-P interaction. The P-gstP binding occurred only on expression of the proteins in the same cell and was mapped to amino acids 345-411. We also show that full-length and deletion gstV and gstW proteins bound NPo protein when these sets of proteins were coexpressed and have identified one required region from amino acids 78-316. Neither gstV nor gstW bound NP assembled into nucleocapsids. Furthermore, both V and W proteins lacking the N-terminal 77 amino acids inhibited DI-H genome replication in vitro, showing the biological relevance of the remaining region. We propose that the specific inhibition of genome replication by V and W proteins occurs through interference with either the formation or the use of the NPo-P encapsidation substrate.
authors.affiliation: Department of Molecular Genetics and Microbiology, University of Florida College of Medicine, Gainesville 32610-0266, USA.
authors.forename: S M
authors.initials: SM
authors.lastname: Horikami
authors.forename: S
authors.initials: S
authors.lastname: Smallwood
authors.forename: S A
authors.initials: SA
authors.lastname: Moyer
mesh_terms: D000818:Animals; D002522:Chlorocebus aethiops; D003673:Defective Viruses / Q000235:genetics; D017353:Gene Deletion; D016679:Genome, Viral; D006801:Humans; D019251:Nucleocapsid / Q000378:metabolism; D019590:Nucleocapsid Proteins; D009698:Nucleoproteins; D012367:RNA, Viral / Q000096:biosynthesis*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D018108:Respirovirus / Q000235:genetics / Q000378:metabolism*; D014407:Tumor Cells, Cultured; D014709:Vero Cells; D014758:Viral Core Proteins / Q000235:genetics / Q000378:metabolism*; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D019590:Nucleocapsid Proteins; D009698:Nucleoproteins; D012367:RNA, Viral; D011993:Recombinant Fusion Proteins; D014758:Viral Core Proteins; D014764:Viral Proteins