J Virol Methods. 2018 Feb 12. pii: S0166-0934(17)30556-6. doi: 10.1016/j.jviromet.2018.02.010. [Epub ahead of print]
Fluorescent protein tagged hepatitis B virus capsid protein with long glycine-serine linker that supports nucleocapsid formation.Chen JY1, Gan CY2, Cai XF2, Zhang WL2, Long QX2, Wei XF2, Hu Y2, Tang N2, Chen J2, Guo H3, Huang AL4, Hu JL5. Author information 1Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Department of Infectious Diseases, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China; Department of Clinical Laboratory, The First Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong, China; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases (CCID), Hangzhou, China.2Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Department of Infectious Diseases, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China.3Department of Microbiology and Immunology, Indiana University School of Medicine, United States.4Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Department of Infectious Diseases, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases (CCID), Hangzhou, China. Electronic address: [email protected].5Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Department of Infectious Diseases, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases (CCID), Hangzhou, China. Electronic address: [email protected].
AbstractFusion core proteins of Hepatitis B virus can be used to study core protein functions or capsid trafficking. A problem in constructing fusion core proteins is functional impairment of the individual domains in these fusion proteins, might due to structural interference. We reported a method to construct fusion proteins of Hepatitis B virus core protein (HBc) in which the functions of fused domains were partially kept. This method follows two principles: (1) fuse heterogeneous proteins at the N terminus of HBc; (2) use long Glysine-serine linkers between the two domains. Using EGFP and RFP as examples, we showed that long flexible G4S linkers can effectively separate the two domains in function. Among these fusion proteins constructed, GFP-G4S186-HBc and RFP-G4S47-HBc showed the best efficiency in rescuing the replication of an HBV replicon deficient in the core protein expression, though both of the two fusion proteins failed to support the formation of the relaxed circular DNA. These fluorescent protein-tagged HBcs might help study related to HBc or capsids tracking in cells.
KEYWORDS: Hepatitis B virus; core protein; engineering; fusion proteins