Objective To clone and express HCMV UL123 gene exon 2,3(ie1-exon2,3) in bacterial two-hybrid bait plasmid,and identify its self-activation property.Methods HCMV ie1-exon2,3 carried on pTWIN1/ie1 recombinant was amplified by PCR and cloned into the pBT plasmid,which was transformed into E.coli XL1-Blue MRF' Kan host strain.The positive recombinant was identified by PCR,restriction enzyme digestions and sequencing analysis.The verified plasmid was transformed into bacterial two-hybrid system reporter strain.The soluble fusion protein was analyzed by SDS-PAGE and Western blot.The self activation effect of the recombinant was then tested.Results Bacterial two-hybrid pBT/ie1-exon2,3 bait plasmid was successfully constructed.The corresponding soluble fusion protein rIE1-N_(85)/?C1 was expressed in bacterial two-hybrid system reporter strain,and didn't show self-activation property.Conclusion Bacterial two-hybrid pBT/ie1-exon2,3 bait plasmid without self-activation property was successfully constructed,and it can be used to screen the library of fetal brains.

There are many problems in the training mode of traditional forensic undergraduates, such as the lag of curriculum setting, the lack of interdisciplinary and the lack of practical training. Based on the teaching practice of forensic undergraduates in Central South University, this study puts forward the following four reform schemes: ①advancing the setting of forensic medicine curriculum to strengthen the integration of specialized courses with basic medicine and clinical medicine courses; ②increasing related courses to intensify interdisciplinary teaching; ③introducing online teaching mode of virtual simulation to enrich the content of undergraduate forensic medical education; ④expanding the scope of joint classroom teaching inside and outside the school to realize the two-way rapid update of practical and theoretical resources. The purpose of this paper is to provide new ideas and directions for training forensic talents who are more suitable for the development of the times.

OBJECTIVETo investigate the roles of Domain I and Domain II of hepatitis C virus (HCV) 5' untranslated region (UTR) in the translation initiation activity of HCV 5'UTR in different host cell lines.

METHODSThe eukaryotic expression plasmid pCMVNCRLuc (pCN1), in which full-length HCV 5'UTR regulates firefly luciferase expression, was modified by deleting Domain I and the downstream single-stranded sequence (43 bp in total) from the UTR (pCNl-d2), Domain I with the downstream single-stranded sequence and Domain II (118 bp in total) from the UTR (pCNl-d3), or the total UTR (pCNl-d5). The modified plasmids were transfected via liposome into different cell lines with pRL-TK plasmid co-transfected as the normalization control. At 36 h after the transfection, the total cellular RNA was harvested for semi-quantitative RT-PCR, and the relative expression activities of luciferase were assayed with a dual luciferase reporter gene assay system. The translation initiation activities of the truncated HCV 5'UTRs in different translation systems were analyzed.

RESULTSDeletion of Domain I and the downstream single-stranded sequence caused no significant changes of the translational activity of HCV 5'UTR in Hela or C6 cells, but decreased the translational activity by 46% in L-02 cells and increased the translational activity by 46% in 293T cells. Deletion of both Domain I and Domain II resulted in decreased translational activity of HCV 5'UTR by 51% in HeLa cells, but increased the translational activity by 40% in L-02 cells, 60% in C6 cells and 135% in 293T cells.

CONCLUSIONSDomain I and Domain II of HCV 5'UTR perform cell type-specific roles in HCV IRES-driven translation initiation.

5' Untranslated Regions ; Genes, Reporter ; HeLa Cells ; Hepacivirus ; genetics ; Humans ; Luciferases ; Plasmids ; Protein Biosynthesis ; genetics ; RNA, Viral ; genetics ; Transfection