title: Annexin 2 is a host protein binding to classical swine fever virus E2 glycoprotein and promoting viral growth in PK-15 cells.
abstract: Glycoprotein E2 of classical swine fever virus (CSFV) is a key determinant and major immunogen for viral entry and immunity, but little is known about its interaction with host proteins. In a previous study, we showed by proteomic analysis that cellular membrane protein annexin 2 (Anx2) was up-regulated in PK-15 cells following CSFV infection, but its function in CSFV replication remains unknown. In the present study we observed the interaction of Anx2 with CSFV E2 following infection of PK-15 cells by co-immunoprecipitation (Co-IP), mass spectrometry, Western blot and confocal laser scanning microscopy. The interaction between CSFV E2 and Anx2 was further confirmed in an E2-expressing PK-15 cell line, in which up-regulation of Anx2 was also observed, indicating that E2 alone can interact with, and increase, the expression of Anx2 protein. Further studies showed that siRNA-mediated knock-down and plasmid-mediated over-expression of Anx2 in PK-15 cells inhibited and increased CSFV replication and proliferation respectively. Remarkably, treatment of PK-15 cells with Anx2-specific polyclonal antibody prior to virus infection significantly inhibited CSFV multiplication, indicating that Anx2 is a cellular membrane protein likely associated with CSFV entry into cells. In conclusion, Anx2 is the novel host protein identified to interact with CSFV E2 and promote CSFV multiplication. These observations provide support for the potential use of Anx2 as a cellular target for the development of novel anti-CSFV therapies.
authors.affiliation: Veterinary College of Jilin University, Xi An Road 5333, Changchun 130062, China; Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Institute of Military Veterinary, Academy of Military Medical Sciences, Liuying West Road 666, Changchun 130122, China.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Yang
authors.affiliation: Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Institute of Military Veterinary, Academy of Military Medical Sciences, Liuying West Road 666, Changchun 130122, China.
authors.forename: Zixue
authors.initials: Z
authors.lastname: Shi
authors.affiliation: Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Institute of Military Veterinary, Academy of Military Medical Sciences, Liuying West Road 666, Changchun 130122, China.
authors.forename: Huancheng
authors.initials: H
authors.lastname: Guo
authors.affiliation: Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Institute of Military Veterinary, Academy of Military Medical Sciences, Liuying West Road 666, Changchun 130122, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Qu
authors.affiliation: Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Institute of Military Veterinary, Academy of Military Medical Sciences, Liuying West Road 666, Changchun 130122, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Institute of Military Veterinary, Academy of Military Medical Sciences, Liuying West Road 666, Changchun 130122, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China. Electronic address: changchun_tu@hotmail.com.
authors.forename: Changchun
authors.initials: C
authors.lastname: Tu
mesh_terms: D000818:Animals; D017306:Annexin A2 / Q000378:metabolism*; D015153:Blotting, Western; D002460:Cell Line; D006692:Classical Swine Fever Virus / Q000502:physiology*; D054884:Host-Pathogen Interactions; D047468:Immunoprecipitation; D013058:Mass Spectrometry; D018613:Microscopy, Confocal; D011485:Protein Binding; D013552:Swine; D014759:Viral Envelope Proteins / Q000378:metabolism*; D014779:Virus Replication
chemical_list: D017306:Annexin A2; D014759:Viral Envelope Proteins; C087086:glycoprotein E2, classical swine fever virus
keywords: Annexin 2; Classical swine fever virus; E2; Interaction