title: ORF2 protein of porcine circovirus type 2   promotes phagocytic activity of porcine   macrophages by inhibiting proteasomal   degradation of complement component 1,   q subcomponent binding protein (C1QBP)   through physical interaction.
abstract: Defining how each ORF of porcine circovirus type 2 (PCV2) manipulates the host immune system may be helpful to understand the disease progression of post-weaning multisystemic wasting syndrome. In this study, we demonstrated a direct interaction between the PCV2 ORF2 and complement component 1, q subcomponent binding protein (C1QBP) within the cytoplasm of host macrophages. The physical interaction between PCV2 ORF2 and C1QBP inhibited ubiquitin-mediated proteasomal degradation of C1QBP in macrophages. Increased stability of C1QBP by the interaction with PCV2 ORF2 further enhanced the phagocytic activity of porcine macrophages through the phosphoinositol 3-kinase signalling pathway. This may explain the molecular basis of how PCV2 ORF2 enhances the phagocytic activity of host macrophages.
authors.affiliation: Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Republic of Korea.
authors.forename: Chang-Yong
authors.initials: CY
authors.lastname: Choi
authors.affiliation: Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Republic of Korea.
authors.forename: Hae-Na
authors.initials: HN
authors.lastname: Oh
authors.affiliation: Department of Biomedical Laboratory Science, College of Health Science, Cheongju University, Cheongju-si 360-764, Republic of Korea.
authors.forename: Suk
authors.initials: S
authors.lastname: Jun Lee
authors.affiliation: Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Republic of Korea.
authors.forename: Taehoon
authors.initials: T
authors.lastname: Chun
mesh_terms: D000818:Animals; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D018173:Circoviridae Infections / Q000378:metabolism* / Q000821:virology; D017925:Circovirus / Q000235:genetics / Q000378:metabolism*; D008264:Macrophages / Q000276:immunology / Q000378:metabolism*; D010587:Phagocytosis; D010802:Phylogeny; D053570:Porcine Postweaning Multisystemic Wasting Syndrome / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism*; D011485:Protein Binding; D059748:Proteolysis; D013552:Swine; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D002352:Carrier Proteins; D014764:Viral Proteins; D046988:Proteasome Endopeptidase Complex