1.Construction and expression of expressive vector of binding protein 4 spliced variant HBeBP4A of HBeAg in yeast cell
Jiankang ZHANG ; Jun CHENG ; Jiang GUO
Medical Journal of Chinese People's Liberation Army 1982;0(03):-
Objective To study the exact function of HBeBP4A so as to investigate the gene expression of HBeBP4A in yeast cell.Methods Reverse transcription polymerase chain reaction(RT-PCR)was employed to amplify the gene of HBeBP4A from recombinant plasmids pcDNA 3.1/myc-HisA-HBeBP4A,and the gene was cloned into pGEM-T vector.The gene of HBeBP4A was cut from pGEM-T-HBeBP4A vector and cloned into yeast expressive plasmid pGBKT7,and pGBKT7-HBeBP4A was then transformed into yeast AH109.The yeast protein was isolated and analyzed with sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE)and Western blotting hybridization.Results HBeBP4A gene was successfully amplified and identified by DNA sequencing.The digested fragment was cloned into pGBKT7 vector and transformed into yeast cell AH109.The SDS-PAGE and Western blotting assay showed that the relative molecular weight of the expressed product was about 61.37kD,and HBeBP4A protein existed in yeast cells.Conclusion The findings suggested that HBeBP4A was successfully expressed into yeast system.
2.Up-regulation of thioredoxin reductase 1 gene promoter by hepatitis B virus pre-S2 protein
Dong JI ; Jun CHENG ; Jiang GUO
Medical Journal of Chinese People's Liberation Army 2001;0(08):-
Objective To investigate the activity of HBV pre-S2 protein on thioredoxin reductase 1 (TXNRD1) gene promoter. Methods TXNRD1 gene promoter DNA sequence was identified in GenBank by bioinformatics and amplified from HepG2 genome by polymerase chain reaction (PCR). The amplified product was cloned into pCAT3-Basic reporter vector,named pCAT3-TXNRD1p. The HepG2 cells were transfected by pCAT3-TXNRD1p,and then co-tranfected by pCAT3-TXNRD1p and pcDNA3.1(-)-preS2 plasmids. The choloraphenical acetyltransferase(CAT)activity was assessed by enzyme linked immunosorbent assay(ELISA). Results The results indicate that HepG2 cells transfected by pCAT3-TXNRD1p had higher activity of CAT than that transfected by pCAT3-Basic. The expression of CAT in HepG2 cells co-transfected by pCAT3-TXNRD1p and pcDNA3.1(-)-preS2 was 2.2 times higher than that with pCAT3-TXNRD1p. Conclusions The TXNRD1 gene promoter identified in this study has transcription activity and HBV pre-S2 protein can transactivate the expression of TXNRD1 gene.
3.Screening of promoter DNA-binding protein of iNOS gene by phage display technique from human liver cDNA library
Fengjin GUO ; Jun CHENG ; Yanwei ZHONG
Medical Journal of Chinese People's Liberation Army 1981;0(04):-
Objective To screen promoter DNA-binding protein of inducible nitric oxide synthase gene by using phage display technique from human liver cDNA library, and to study the expression and regulation mechanism of iNOS gene. Methods The sequence of iNOS promoter was identified in GenBank by bioinformatics based on the open reading frame(ORF) of iNOS gene and amplified from HepG2 genome by polymerase chain reaction (PCR). The amplified product was subcloned into pCAT3-Basic reporter vector, named as pCAT3-iNOSp. The HepG2 cell line was then transfected with pCAT3-Basic to serve as negative control, and pCAT3-promoter which contains the promoter region of CMV served as the positive control subject, and pCAT3-iNOSp served as the test subject, respectively. The choloraphenical acetyltransferase(CAT)activity was determined by enzyme linked immunosorbent assay(ELISA) kit. The T7 Select human liver cDNA library was biopanned and positive clones were selected. After screening, positive plaque was performed to amplify and PCR products were sequenced. Results The expression of CAT in transfection of pCAT3-PS1TP1p was 4.2 times as higher as pCAT3-Basic plasmid. Sequence analysis was performed in 12 positive plaque, which were the iNOSp binding protein. Conclusion The iNOS gene promoter identified in this study has shown to have transcription activity,and iNOS promoter DNA-binding proteins havs been screened. The results will be useful for further study of the expression and regulation mechanism of iNOS in liver cell.
4.Screening of promoter DNA-binding protein of cyclin B2 gene by phage display technique from human liver cDNA library
Jiang GUO ; Jun CHENG ; Longfeng ZHAO
Medical Journal of Chinese People's Liberation Army 2001;0(12):-
Objective To screen promoter binding protein of cyclin B2 by using human liver cDNA library, and investigate the expression and regulation mechanism of cyclin B2 gene. Methods By using cyclin B2 biotinylated promoter DNA as the selective molecule, the T7select human liver cDNA library was biopanned and positive clones were selected. After screening, positive plaques were performed to amplify for inserted DNA fragment, and the DNA fragment was cloned into pGEM-Teasy vector. Results Sequence analysis was performed in 20 positive plaques, and the full length sequences were obtained with bioinformatics method and searched for homologous DNA sequence from GenBank, altogether 6 coding sequences were obtained, all of which were known ones. Conclusion Cyclin B2 promoter binding proteins were screened. The results will be useful for further study the expression and regulation mechanism of cyclin B2.
5.Cloning of human gene 5 trans-activated by pre-S1 protein of hepatitis B virus
Jiankang ZHANG ; Jiang GUO ; Jun CHENG
Medical Journal of Chinese People's Liberation Army 1983;0(05):-
Objective To clone a new human gene 5 trans-activated by pre-S1 protein of hepatitis B virus (HBV), PS1TP5, and explore its structure and function by bioinformatics analysis. Methods PS1TP5 was amplified by reverse transcription-polymerase chain reaction (RT-PCR) technique by using HepG2 cDNA as template and inserted into pGEM-T vector by TA cloning. Recombinant eukaryotic expression vector pcDNA TM 3.1/myc-His A-PS1TP5 had been constructed by subcloning, followed by restriction enzyme digestion analysis and sequencing. Bioinformatic methods were used to analyze its possible physical and chemical characters, structure, and function. Results PS1TP5 was successfully amplified and cloned into pGEM-T and pcDNA TM 3.1/myc-His A vector by RT-PCR from HepG2 cDNA. The new gene had been confirmed by sequencing after PCR identification and restriction enzyme digestion and named as PS1TP5 because of its trans-active function. The sequence for the PS1TP5 gene had been deposited into GenBank, the accession number was AY427953. Bioinformatics analysis showed that its ORF was 438bp and translated a protein of 145 aa. Conclusion A new gene-PS1TP5 has been recognized, and its recombinant eukaryotic expression vector (pcDNA TM 3.1/myc-His A-PS1TP5) has been constructed. These results will certainly bring some new clues for the study of the biological function of new gene and pathogenesis of chronic hepatitis B.
6.Screening and cloning of the target genes transactivated by HCV FTP2 protein using suppression subtractive hybridization technique
Jiang GUO ; Jun CHENG ; Longfeng ZHAO
Chinese Journal of Infectious Diseases 2001;0(05):-
Objective To clone and identify human genes transactivated by homo sapiens HCV FTP2 by constructing a cDNA subtractive library with suppression subtractive hybridization tech- nique.Methods Suppression subtractive hybridization(SSH)and bioinformatics techniques were used for screening and cloning of the target genes transactivated by HCV FTP2.The mRNA was iso- lated from HepG2 cells transfected pcDNA3.1(-)-HCV FTP2 and pcDNA3.1(-)empty vector re- spectively,and SSH method was employed to analyze the differentially expressed DNA sequence be- tween the two groups.After digestion with restriction enzyme Rsa I,small-size cDNAs were ob- tained.Then tester cDNA was divided into two groups and ligated to the specific adaptor I and adap- tor 2 respectively.After tester cDNA was hybridized with driver cDNA twice and underwent two times of nested PCR and then was subcloned into T/A plasmid vectors to set up the subtractive library. Amplification of the library was carried out with E.coli strain DH5?.Futhermore,the cDNA was se- quenced and analyzed in GenBank with Blast search after PCR.Results The subtractive library of genes transactivated by HCV FTP2 was constructed successfully.The amplified library contains 71 positive clones.Colony PCR shows that 56 clones contain 200~1000 hp inserts.Sequence analysis was performed in 24 clones randomly,and the full length sequences were obtained with bioinformatics method.Altogether 20 coding sequences in total were obtained,consisting of 19 known and 1 un- known.Conclusion The obtained sequences may be target genes transactivated by HCV FTP2,and some genes coding proteins involved in cell cycle regulation,metabolism and cell apoptosis.
7.Up-regulating effect of hepatitis C virus core protein on inducible nitric oxide synthase gene promoter
Feng-Jin GUO ; Jun CHENG ; Yan LIU ;
Chinese Journal of Infectious Diseases 1997;0(04):-
Objective To investigate the transactivating effect of hepatitis C virus(HCV)core protein on inducible nitric oxide synthase(iNOS)gene promoter and the molecular biological mecha- nisms of HCV pathogenesis.Methods Polymerase chain reaction(PCR)technique was employed to amplify the sequence of iNOS promoter by using HepG2 genomic DNA as template,and the product was cloned into pGEM-T vector.The iNOSp gene was cut from T-iNOSp by KpnⅠand XhoⅠ,and then was cloned into pCAT3-Basic,the constructed vector was named as pCAT3-iNOSp,pCAT3-iN- OSp was transfected into the LO_2 cell line.LO_2 cell was also cotransfected with pcDNA3.1(-)-core and pCAT3-iNOSp by FuGENE 6 transfection reagents.The LO_2 cells transfected with pCAT3-Basic was used as negative control.The activity of CAT in LO_2 cells was detected by an ELISA kit after 48 hours,which reflected the transactivating function of HCV core protein to iNOS gene promoter.Re- sults The expressive vector pcDNA3.1(-)-core and report vector pCAT3-iNOSp had been construc- ted and confirmed by restriction enzyme digestion and sequencing.The expression of CAT in LO_2 cells transfected with pCAT3-iNOSp and peDNA3,1(-)-core was 11 times as higher as that of pCAT3-bas- ic,and 6 times as higher as that of pCAT3-iNOSp.Conclusion It is suggested that HCV core protein can transactivate iNOS gene promoter.
9.Molluscicidal experiment of endophytes from Pseudolarix kaempferi Gord
Shangbin GUO ; Jun CHEN ; Jia HE ; Xi CHENG ; Nan ZHONG
Chinese Journal of Schistosomiasis Control 1989;0(04):-
Objective To screen 18 endophytes from Pseudolarix kaempferi Gord for molluscicidal effect and identify them by morphology. Methods Molluscicidal tests were performed according to the immersion test suggested by WHO and the strain screened was identified by the slide culture. Results The mortality rates of snails immersed by JJ18 broth salified (pH=7) were 26.7%, 76.7% and 100.0% for 24,48 h and 72 h, respectively, and 53.3% and 86.7% in 5% and 10% concentrations of JJ18 broth, respectively. The active components were extracellular moiety of the broth which had no acute toxicity to fish, and JJ18 strain belonged to Aspergillus. Conclusion Extracellular moiety of endophyte JJ18 from Pseudolarix kaempferi Gord is a new resource of molluscicide.
10.Analysis of X-ray radiation doses from different types of intervention for cardiovascular patients
Jun FENG ; Ailing WANG ; Jinglin CHENG ; Jie GUO
Chinese Journal of Radiological Medicine and Protection 2012;32(4):416-419
Objective To explore the X-ray radiation dose to patients from different cardiovascular interventional procedures and analyze the dose-affecting factors.Methods In accordance with the A,B,C operators,442 patients undergoing cardiovascular interventional procedures were collected,including single coronary angiography (CAG),percutaneous coronary intervention ( PCI ),radiofrequency catheter ablation (RFCA),congenital heart disease intervention (CHD) and permanent cardiac pacemaker implantation (PCPI),to observe dose area product (DAP),cumulative radiation dose (CD),fluoroscopy time.Results CD values of patients in groups of CAG,PCI,RFCA,CHD,PCPI were (0.34 ±0.23),(1.33 ±0.76),(0.71 ±0.43),(0.27 ±0.22) and (0.92±0.42) Gy and DAP values were (34.18 ±23.33),(135.92 ±81.14),(79.79 ±50.66),(27.93 ±23.66),and (94.60 ±48.11 ) Gy·cm2,respectively.Fluoroscopy time were (4.82 ±3.73),( 16.64 ±9.01 ),( 17.04 ± 15.29),(9.60 ±5.97)and (7.31 ±6.45) min.DAP values and fluoroscopy time were highly correlated (r =0.84,P < 0.05 ).Conclusions There is significant difference in radiation dose for cardiovascular interventional procedures.Radiation dose and fluoroscopy time are directly related to surgeons' proficiency in operations.Improvement of operation proficiency should be carried out to reduce the patients' radiation dose.