title: Interactions of the borna disease virus P, N, and X proteins and their functional implications.
abstract: Borna disease virus (BDV) causes persistent central nervous system infection and behavioral disturbances in warm-blooded animals. Protein interaction studies were pursued to gain insight into the functions of the putative nucleoprotein (N), phosphoprotein (P), atypical glycoprotein (gp18), and X protein (X) of BDV. Coimmunoprecipitation experiments indicated that N and P, and P and X, form complexes in infected cells. Two-hybrid analyses confirmed interactions between P and P, P and X, and P and N, but not between P and gp18, N and gp18, X and gp18, or X and N. Analysis of P truncation mutants identified three nonoverlapping regions important for oligomerization (amino acids (aa) 135-172), and binding to X (aa 33-115) or N (aa 197-201). Coexpression of X stimulated oligomerization of P but decreased N-P complex formation. Immunocytochemistry of transfected noninfected CHO cells demonstrated that the distribution of X is dependent upon the presence of P-X expressed alone was found predominantly in the cytoplasm whereas coexpression of X and P resulted in nuclear localization. Immunocytochemistry of infected cells revealed nuclear colocalization of P and X. Interactions of P, N, and X may have implications for regulation of BDV transcription/replication and ribonucleoprotein assembly.
authors.affiliation: Department of Neurology, University of California, Irvine, California 92697-4292, USA.
authors.forename: M
authors.initials: M
authors.lastname: Schwemmle
authors.forename: M
authors.initials: M
authors.lastname: Salvatore
authors.forename: L
authors.initials: L
authors.lastname: Shi
authors.forename: J
authors.initials: J
authors.lastname: Richt
authors.forename: C H
authors.initials: CH
authors.lastname: Lee
authors.forename: W I
authors.initials: WI
authors.lastname: Lipkin
mesh_terms: D000818:Animals; D001891:Borna disease virus / Q000235:genetics / Q000502:physiology*; D016466:CHO Cells; D019556:COS Cells; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism / Q000648:ultrastructure; D006224:Cricetinae; D003545:Cysteine / Q000378:metabolism; D004268:DNA-Binding Proteins; D005656:Fungal Proteins / Q000096:biosynthesis; D046911:Macromolecular Substances; D008715:Methionine / Q000378:metabolism; D016366:Open Reading Frames; D014176:Protein Biosynthesis; D055503:Protein Multimerization; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D014162:Transfection; D020798:Two-Hybrid System Techniques; D014764:Viral Proteins / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D004268:DNA-Binding Proteins; D005656:Fungal Proteins; C052130:GAL4 protein, S cerevisiae; D046911:Macromolecular Substances; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D014764:Viral Proteins; D008715:Methionine; D003545:Cysteine