Objective To screen and identify proteins that interact with the hepatitis C virus core protein by means of T7-phage display system. Methods The hepatitis C virus core protein was expressed by prokaryotic expression and used as selected molecule to biopan the T7 human liver cDNA library. The selected positive clones were identified by DNA sequence and analyzed with BLAST program in GenBank. Results After BLAST in all positive clones, one protein--Smad interacting protein 1 (SIP1) was found to interact with the hepatitis C virus core protein. Conclusion T7-phage display system is a convenient, rapid and effective method for screening interacting proteins.

Objective To optimize the method of transcription activator‐like effector transcription factors (TALE‐TFs) con‐struction ,some improvement and adaption were made based on the traditional methods .Methods We first constructed the basic tandem fragments with different length ,including trimer ,tetramer ,pentamer and hexamer by Golden Gate cloning technique and PCR ,then the procedure with the highest efficacy was chosen to construct our TALE‐TFs .To determine the function of the TALE‐TFs ,the plasmid pminCMV with the specific binding sequence of TALE‐TFs was constructed by fragment substitution reaction (FSR) .The transcription activating function of TALE‐TFs was confirmed by the intensity of red fluorescence ,after TALE‐TFs , pEGFP‐N1 and pminCMV plasmid were co‐transfected into 293HEK cells .Results An optimized method for TALE‐TFs construc‐tion and functional assay was established .Conclusion This method can potentially be wildly used in fields that the expression of some constitutively expressed genes needs to be modified .

Objective To analyze the characteristics and hepatotropism of this negative element HBVnt453-250 sequence.Methods pHBv453-250,pHBV250-453.plucHBV453-250 and plucHBV250-453 were constructed,with luciferase and enhanced green fluorecence protein(EGFP)gene as the reporter gene,respectively.After transfection of HepG2 cells with these plasmids,luciferase assays,real-time PCR and western blot assays were used to detect the gene transcription and expression level.The SV40 promoter of pGL3 control and pHBV453-250 were replaced by the cytomegalovirus early promoter,resulting in plasmids pCMVcontrol(luc)and pCMV453-250(luc).Results Compared with pHBV453-250,the mutant plasmids.with the inhibitory element inserted in difierent site or inverted orientation.exerted similar downregulation of Juciferase gene transcription and expression.Western blot analysis demonstrated the similar repression when EGFP was used as the reporter gene.By transfeeted to HepG2 cell line,the plasmid pCMV453-250(1UC)could reduce lneiferase activity(36.56%)compared with pCMLcontrol(luc).When the plasmids plueHBV453-250 and plucHBV250-453 were transfected to non-liver cell lines(A549,HeLa),luciferase gene was expressed weakly,compared with that of pGL3control(P＜0.05).Conclusion The inhibitory effect of HBVnt453-250 sequence acted in both orientation-and position-independent manners,and had no promoter selectivity and funotioned in hepatocyte-independent manner.

Objective:To gain insight into the mechanism responsible for clearance of natural hepa DNA virus infections.Methods:A group of seven 2～3 month old ducks were infected intravenously with 10～20 ml DHBV positive serum containing 5?10 7 genomes/ml.Following inoculation,ducks were bled at weekly intervals to obtain serum samples for analysis of DHBV DNA and DHBsAg and anti DHBV antibodies.Peripheral blood mononuclear cells were collected at 10,35 days postinoculation(p.i) and used to conduct antigen specific blastogenesis assay.Liver samples were obtained at 5,30,60 days p.i for analysis of DHBV DNA and surface antigens and liver histology.Results:Infection of all 7 animals with approximately 5?10 8～1?10 9 DHBV genomes led to a transient viremia after an incubation period of 1 to 2 weeks.Liver samples contained multiple copies of all of the expected species of DHBV DNA replicative intermediates,including DHBV cccDNA during the peak of viremic phase.Further analysis showed that the absence of a prolonged viremia could be explained by immediate antigen specific blastogenesis and high titer of antibody response.Meanwhile,there was no obvious evidence of liver cell injury during transient DHBV infection.Conclusion:These results demonstrate that noncytopathic antiviral mechanisms make a role in hepa DNA virus clearance.

The management of the scientific research files is an important basic work at the college,which is of great significance to the research work in both school and the scientific research organizations.However,some researchers and managers are lack of file consciousness and the management system remains unadapted to the new condition.These reasons result in the use of the dossiers inadequate or even absent.Therefore,it seems necessary and important for the perfection of the scientific research file work to take essential measures:establishing a scientific and reasonable file system,improving the file management regulation,and increasing the utilization ratio of the dossiers.

Objective:To construct a recombinant eukaryotic expression vector containing gene encoding 18 000 outer membrane protein from human Helicobacter pylori(H.pylori) and be expressed in COS-7 cell,and lay the foundation for the exploiting DNA vaccine of Hp.Methods:The target genes encoding 18 000 outer membrane protein were acquired from the prokaryotic expression vector pET32a(+)/528 by XholⅠ,KpnⅠ digestion simultaneously,in the same way,the pcDNA3.1 was digested by XhoⅠ,KpnⅠ digestion simultaneously,and the objective genes and pcDNA3.1 were extracted out of agarose electrophoresis with gel kit,and connected by T4 ligase.The recombinant vector pcDNA3.1/528 was used to select and transform,meanwhile express in COS-7 cell.The expressions of recombinant eukaryotic vector in COS-7 cell were investigated by reverse transcriptive-polymerase chain reaction and Western.Results:The gene had inserted into eukaryotic vector was the target gene encoding 18 000 outer membrane protein by enzyme digestion analysis,and objective gene was amplified from COS-7 cell transfected with pcDNA3.1/528 by RT-PCR,the Western showed that recombinant eukaryotic vector could be expressed in COS-7 cell.Conclusion:The recombinant eukaryotic vector pcDNA3.1/528 was constructed and expressed in COS-7 cell successfully.The results obtained lay the foundation for research on development of H.pylori DNA vaccine.

Hepatitis B virus (HBV) DNA replication takes place in the viral capsid that consists of 180 or 240 copies of HBV capsid (HBc or core) protein. The monomeric core protein contains an apical loop region that forms the spikes on the surface of viral capsid upon core dimerization and capsid assembly. To investigate the impact on HBV DNA replication through gene engineering at the spike of HBV capsid. plasmids expressing engineered HBc with linker-fused enhanced green fluorescent protein (EGFP) or shortened EGFP insertion at the spike region were constructed by Restriction Digestion and Ligation-independent Cloning (RLIC). The wildtype or mutant HBc construct was cotransfected with HBV1.1c(-), a plasmid containing 1.1 unit-length HBV genome with deficiency in HBc expression, into HEK293 cells, respectively. GFP signal was observed through a fluorescence microscope and HBV DNA replicative intermediates were assayed by Southern blotting to determine the expression and functions of different recombinants. Our results demonstrated that the RLIC method was effective to generate deletion or insertion in the apical loop region of HBc. Both HBc-EGFP recombinants with different linkers produced green fluorescence but with different subcellular distribution pattern. However, HBV DNA replication was not detected with the trans-complementation of these two HBc recombinants. In addition, other recombinants including the one only with the deletion of aa79-80 failed to support HBV replication. Taken together, our results suggest that RLIC is a robust method which can be broadly applied in gene engineering; different peptide linkers may have different influences on the functions of an engineered fusion protein; and HBc aa79-80 play a critical role for HBc to support HBV DNA replication.
Capsid Proteins ; genetics ; Cloning, Molecular ; Genetic Engineering ; methods ; Green Fluorescent Proteins ; biosynthesis ; genetics ; HEK293 Cells ; Hepatitis B Core Antigens ; biosynthesis ; genetics ; Hepatitis B virus ; genetics ; physiology ; Humans ; Mutation ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; Transfection ; Virus Replication

Objective To investigate the seroepidemiology of Epstein-Barr virus (EBV) and human immunodeficiency virus (HIV) in adult men who have sex with men (MSM) in Chongqing area. Methods Nonprobability sampling method was used to test EB-CA-IgG, EB-NA-IgG and EB-VCA-IgM in the sera of 1082 MSMs from the clinical trials of HIV/AIDS treatments in Chongqing area from 2012 to 2015, and 1059 healthy individuals by means of enzyme-linked immunosorbent assay. The results were analyzed by Chi-square test. The difference was considered statistically significant when P<0.05. Results The 1082 MSM included 130 HIV positive and 952 HIV negative subjects. The prevalence of prior EBV infection was 92.6% in total MSM population, 88.5% in HIV-positive MSM, and 93.2% in HIV-negative MSM. The prevalence in total MSM and HIV negative MSM was significantly higher than that in control group (89.9%). Prior EBV infection was not?found?in?0.5%?of?the?total?MSM,?0.8%?of?HIV?positive?MSM?and?0.4%?of?HIV?negative?MSM,?all?significantly?lower?than?that?of control group (5.0%) (P<0.05).?Finally,?the?rate?of?EBV?reactivation?in?HIV?positive?MSM?(10.0%)?was?significantly?higher?than?that in control group (3.8%) and in HIV negative MSM group(4.1%) (P<0.005). Conclusions EBV infection is highly prevalent in MSM, higher than that in the general population. The rate of EBV reactivation in HIV negative MSM is similar to that in general population. The rate of seroepidemiology-based EBV reactivation is significantly higher in HIV positive MSM, which may be associated with the immunocompromised status post HIV infection.

Objective To evaluate the real-time genotyping and quantitative PCR(RT-GQ-PCR)method by comparing it with direct sequence analysis and the multiplex-PCR method.Methods RT-GQ-PCR,direct sequence analysis and the multiplex-PCR method were used to detect HBV genotypes of 113 patient samples with HBV-DNA positive.ResultsThe detection rate of RT-GQ-PCR and direct sequence analysis was 100%,and the multiplex-PCR is 94.69%.The concordance between RT-GQ-PCR and the multiplex-PCR is perfect(Kappa value =0.915),and the consistency of RT-GQ-PCR and direct sequence analysis is pretty good(Kappa value = 0.742),specially at detecting single genotype.Twenty-eight samples with genotypes B and C dual infections were detected by RT-GQ-PCR,but only 19 samples by the multiplexPCR and 13 samples by direct sequence analysis.Conclusion The RT-GQ-PCR is convenient,rapid and accurate in HBV genotyping,especially more sensitive than direct sequence analysis and the multiplex-PCR for detecting dual genotypes.The method is applicable for large-scale epidemiological study.

In order to find microRNA associated with HBV infection and to explore the mechanism of the infection, first of all, we found in our preliminary study that in HepG2 cells transfected with HBV expression plasmid, miR-122 expression was up-regulated, suggesting that miR-122 was related to the HBV infection. On this basis, in the present study, miR-122 and pCH9-HBV1.1 plasmid were cotransfected into HepG2 cells. Southern blot detection result showed that miR-122 can inhibit HBV replication. Using MiRanda computer software, HBx was predicted to be the target sequence of miR-122; Luciferase reporter gene system and Western blot detection of HBx protein expression changes were further used to verify the HBx expression regulated by miR-122. And finally, it can be speculated that miR-122 may affected HBV replication by regulating the expression of HBx.
Gene Expression Regulation, Viral ; drug effects ; Hep G2 Cells ; Hepatitis B virus ; drug effects ; genetics ; physiology ; Humans ; MicroRNAs ; genetics ; Trans-Activators ; genetics ; metabolism ; Transfection ; Virus Replication