Expression of TT Virus ORF2 and the Protein Localization of VP2 in Cos7 Cells
Abstract: Coding sequences of Transfusion transmiffed virus(TT virus or TTV) ORF2 was amplified by PCR, using plasmid pET-His-TTV2 containing the full-length ORF2 of TTV as template. The amplified fragment of 606bp was cloned into plasmid pEGFP-N1 and GFP-VP2 fusion protein was expressed. The recombinant plasmid pEGFPTTV2 was identified by restriction enzyme analysis and PCR. The pEGFPTTV2 was transfected into Cos7 cell line using LipoFectamine 2000, and the transcription products of TTV ORF2 gene in the transfected cells were confirmed by RT-PCR. Localization of the fusion protein was detected by confocal microscope, using PI to visualize the nuclear DNA. The result showed that VP2 was localized in cytoplasm and the inner nuclear membrane. Thus, VP2, as a non- structure protein, may play a role during DNA replication or transcription of TT virus.