title: Porcine circovirus type 2 replicase binds the capsid protein and an intermediate filament-like protein.
abstract: Porcine circovirus type 2 (PCV2) is an important porcine pathogen that establishes persistent subclinical infections but may, on activation, contribute to the development of post-weaning multisystemic wasting syndrome (PMWS). This disease is characterized by weight loss, respiratory or digestive disorders and enlarged lymph nodes with lymphocyte depletion. The molecular mechanisms behind the development of the disease are completely unknown. In order to clarify functions of the different viral proteins and, if possible, to connect these new findings to molecular mechanisms behind the pathogenesis or the viral life cycle, a bacterial two-hybrid screening of a porcine expression library from PK-15A cells was conducted. Using viral proteins corresponding to ORFs 1, 2, 3 and 4 as bait, a number of interactions were identified and two of them were chosen for further characterization. GST pull-down assays confirmed that viral replicase (Rep) interacted with an intermediate filament protein, similar to human syncoilin, and with the transcriptional regulator c-myc. Furthermore, interactions of the viral proteins to each other revealed an interaction between PCV2 Rep and the capsid (Cap) protein and Cap to itself.
authors.affiliation: Department of Molecular Biosciences, Section of Veterinary Immunology and Virology, Swedish University of Agricultural Sciences, Box 588, S-751 23 Uppsala, Sweden.
authors.forename: Sirje
authors.initials: S
authors.lastname: Timmusk
authors.affiliation: Department of Molecular Biosciences, Section of Veterinary Immunology and Virology, Swedish University of Agricultural Sciences, Box 588, S-751 23 Uppsala, Sweden.
authors.forename: Caroline
authors.initials: C
authors.lastname: Fossum
authors.affiliation: Department of Biomedical Sciences and Veterinary Public Health, Section of Parasitology and Virology, Swedish University of Agricultural Sciences, Box 588, S-751 23 Uppsala, Sweden.|Department of Molecular Biosciences, Section of Veterinary Immunology and Virology, Swedish University of Agricultural Sciences, Box 588, S-751 23 Uppsala, Sweden.
authors.forename: Mikael
authors.initials: M
authors.lastname: Berg
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002213:Capsid / Q000378:metabolism; D036022:Capsid Proteins / Q000378:metabolism*; D002460:Cell Line; D018173:Circoviridae Infections / Q000821:virology; D017925:Circovirus / Q000378:metabolism / Q000502:physiology*; D004259:DNA-Directed DNA Polymerase / Q000378:metabolism*; D007381:Intermediate Filament Proteins / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D011485:Protein Binding; D016415:Sequence Alignment; D013552:Swine; D020798:Two-Hybrid System Techniques; D014764:Viral Proteins / Q000378:metabolism*; D014779:Virus Replication
chemical_list: D036022:Capsid Proteins; D007381:Intermediate Filament Proteins; D014764:Viral Proteins; C023140:DNA replicase; D004259:DNA-Directed DNA Polymerase