应用抑制性消减杂交技术筛选NS5ATP5的上调基因

目的 通过抑制性消减杂交(SSH)技术构建丙型肝炎病毒(HCV)NS5A反式激活蛋白5(NS5ATP5)的反式激活相关基因差异表达的cDNA消减文库，筛选HCV NS5ATP5蛋白反式激活靶基因。方法 以HCV NSSATP5表达质粒pcDNA3．1(-)-NSSATP5转染HepG2细胞，以空载体pcDNA3．1(-)为对照；制备转染后的细胞裂解液，从中提取mRNA并合成cDNA，经RsaⅠ酶切后将实验组cDNA分成两组，分别与两种不同的接头衔接，再与对照组cDNA进行两次消减杂交及两次抑制性PCR，将产物与T／A载体连接，构建cDNA消减文库，并转染大肠杆菌进行文库扩增，随机挑选克隆PCR后进行测序及同源性分析。结果 成功构建人HCV NSSATP5蛋白反式激活相关基因差异表达的cDNA消减文库。文库扩增后得到91个白色克隆，进行菌落PCR分析，其中86个均得到100～1000bp插入片段。挑取32个插入片段测序分析。其中包括结缔组织生长因子、纤维连接蛋白、胰岛素样生长因子结合蛋白1等重要的基因。结论 成功筛选出HCV NS5ATP5的上调基因。     

抑制性消减杂交技术筛选NS5ATP13 蛋白的上调基因

目的 应用抑制性消减杂交(SSH)技术构建丙型肝炎病毒(HCV)NS5ATP13蛋白反式激活相关基因差异表达的cDNA消减文库，克隆HCV NS5ATP13蛋白反式激活靶基因。方法 以HCV NS5ATP13表达质粒pcDNA3．1(-)-NS5ATPl3转染HepG2细胞，以空载体pcDNA3．1(-)为对照；制备转染后的细胞裂解液，从中提取mRNA并合成cDNA，经RsaⅠ酶切后将实验组cDNA分成两组，分别与两种不同的接头衔接，再与对照组cDNA进行两次消减杂交及两次抑制性PCR，将产物与T／A载体连接，构建cDNA消减文库，并转染大肠杆菌进行文库扩增，随机挑选克隆PCR后进行测序及同源性分析。结果 成功构建人HCV-NS5ATPl3蛋白反式激活相关基因差异表达的cDNA消减文库。文库扩增后得到102个白色克隆，进行菌落PCR分析，其中96个均得到100～1000bp插入片段。挑取40个插入片段测序分析，其中2个cDNA片段为未知序列，通过生物信息学分析获得其全长序列，已被GenBank收录，另有34个为已知功能序列。结论成功筛选出2个新的cDNA序列，并获得其全长序列，可能为HCV NS5ATPl3蛋白反式激活相关靶基因。     

应用抑制性消减杂交技术克隆筛选丙型肝炎病毒F蛋白结合蛋白2反式激活基因

目的:应用抑制性消减杂交(SSH)技术构建新基因丙型肝炎病毒F蛋白结合蛋白2(HCVFBP2)反式激活基因差异表达的cDNA消减文库,克隆HCVFBP2反式激活相关基因.方法:以HCVFBP2表达质粒pcDNA3.1(-)-FBP2转染HepG2细胞,以空载体pcDNA3.1(-)转染的HepG2细胞为对照;制备转染后的细胞裂解液,提取mRNA并逆转录为cDNA,经RsaⅠ酶切后,将实验组cDNA分成两组,分别与两种不同的接头衔接,再与对照组cDNA进行两次消减杂交及两次抑制多聚酶链反应(PCR),将产物与pGEM-Teasy载体连接,构建cDNA消减文库,转染大肠杆菌进行文库扩增,随机挑选克隆PCR扩增后进行测序及同源性分析.结果:成功构建人类新基因HCVFBP2反式激活基因差异表达的cDNA消减文库.文库扩增后选取48个克隆,进行菌落PCR分析,均得200～1000bp插入片断.挑取30个克隆进行测序,通过生物信息学分析获得28个已知功能基因序列和2个未知功能基因.结论:应用SSH技术成功构建了HCVFBP2反式激活基因差异表达的cDNA消减文库.该文库的建立为阐明HCVFBP2生物学功能提供理论依据.     

应用抑制性消减杂交技术克隆乙型肝炎病毒全S蛋白反式激活基因

目的应用抑制性消减杂交(SSH)技术构建乙型肝炎病毒(HBV)全S蛋白反式激活基因差异表达的cDNA消减文库,克隆HBV全S蛋白反式激活相关基因.方法以HBV全S表达质粒pcDNA3.1(-)-全S转染HepG2细胞,以空载体pcDNA3.1(-)为对照;制备转染后的细胞裂解液,从中提取mRNA并逆转录为cDNA,经RsaI酶切后将实验组cDNA分成两组,分别与两种不同的接头衔接,再与对照组cDNA进行两次消减杂交及两次抑制性PCR,将产物与T/A载体连接,构建cDNA消减文库,并转染大肠杆菌进行文库扩增,随机挑选克隆PCR扩增后进行测序及同源性分析.结果成功构建人HBV全S蛋白反式激活基因差异表达的cD-NA消减文库.文库扩增后得到86个白色克隆,进行菌落PCR分析,均得到100-1000 bp插入片段.挑取35个含有插入片段的阳性克隆测序分析,获得33个已知基因序列,和2个未知基因,通过生物信息学分析获得其全长序列,其中之一命名为全S蛋白反式激活基因1(CSTP1),已在GenBank中注册,注册号:AY553877.未知基因的功能还正在研究中.结论应用SSH技术成功构建了HBV全S反式激活基因差异表达的cDNA消减文库.该文库的建立为进一步阐明HBV全S反式调节的靶基因及致肝病发生的分子生物学机制提供理论依据.     

应用抑制性消减杂交技术筛选丙型肝炎病毒E1蛋白反式激活基因

目的　应用抑制性消减杂交 (SSH)技术构建丙型肝炎病毒 (HCV)E1蛋白反式激活基因差异表达的cDNA消减文库 ,克隆HCVE1蛋白反式激活相关基因。方法　以HCVE1表达质粒pcDNA3 .1( -) E1转染肝母细胞瘤细胞系HepG2细胞 ,以空载体pcDNA3 .1( -)为对照 ;制备转染后的细胞裂解液 ,从中提取mRNA并逆转录为cDNA ,经RsaI酶切后将实验组cDNA分成 2组 ,分别与 2种不同的接头衔接 ,再与对照组cDNA进行 2次消减杂交及 2次抑制性PCR ,将产物与T/A载体连接 ,构建cDNA消减文库 ,并转染大肠杆菌进行文库扩增 ,随机挑选克隆PCR扩增后进行测序及同源性分析。结果　成功构建人HCVE1蛋白反式激活基因差异表达的cDNA消减文库。文库扩增后得到 89个阳性克隆 ,进行菌落PCR分析 ,均得到 10 0 10 0 0bp插入片段。挑取 46个含有插入片段的阳性克隆测序分析 ,获得 44个已知基因序列和 2个未知基因。通过生物信息学分析获得其全长序列 ,已被GenBank收录。结论　应用SSH技术成功构建了HCVE1反式激活基因差异表达的cDNA消减文库。该文库的建立为进一步阐明HCVE1反式调节的靶基因及致肝脏疾病发生的分子生物学机制提供理论依据     

应用抑制性消减杂交技术克隆NS5A-TP4反式激活基因

目的：应用抑制性消减杂交(SSH)技术构建人类新基因NS5A-TP4反式激活基因差异表达的cDNA消减文库，克隆NS5A-TP4反式激活相关基因，了解该基因的可能生物学功能。方法：以NS5A-TP4表达质粒pcDNA3．1(-)-TP4转染HepG2细胞，以空载体pcDNA3．1(-)转染的HepG2细胞为对照；制备转染后的细胞裂解液，从总RNA中提取mRNA并逆转录为cDNA，经RSaⅠ酶切后，将实验组cDNA分成两组，分别与两种不同的接头衔接，再与对照组cDNA进行两次消减杂交及两次抑制多聚酶链反应(PCR)，将产物与pGEM-Teasy载体连接，构建cDNA消减文库，并转染大肠杆菌进行文库扩增，随机挑选克隆PCR扩增后进行测序及同源性分析。结果：成功构建人类新基因NS5A-TP4反式激活基因差异表达的cDNA消减文库。文库扩增后得到63个白色克隆，进行菌落PCR分析，均得到200～1000bp插入片段。挑取含有插入片段的36个克隆进行测序，并通过生物信息学分析获得20种已知功能基因序列和5个未知功能基因。结论：应用SSH技术成功构建了NS5A-TP4反式激活基因差异表达的cDNA消减文库。该文库的建立为阐明NS5A-TP4生物学功能提供理论依据。     

应用抑制性消减杂交技术克隆丙型肝炎病毒 E2蛋白反式调节基因

目的应用抑制性消减杂交(SSH)技术构建丙型肝炎病毒(HCV)E2蛋白反式调节基因差异表达的cDNA消减文库,克隆HCVE2蛋白反式调节相关基因。方法以HCVE2表达质粒pcDNA3.1(-)_E2转染HepG2细胞,以空载体pcDNA3.1(-)为对照,制备转染后的细胞裂解液,从中提取mRNA并逆转录为cDNA,经RsaI酶切后将实验组cDNA分成两组,分别与两种不同的接头衔接,再与对照组cDNA进行两次消减杂交及两次抑制性聚合酶链反应(PCR)扩增,将产物与T/A载体连接,构建cDNA消减文库,并转染大肠杆菌进行文库扩增,随机挑选克隆PCR扩增后进行测序及同源性分析。结果成功构建人HCVE2蛋白反式调节基因差异表达的cDNA消减文库。文库扩增后得到78个阳性克隆,进行菌落PCR分析,均得到100～1000bp插入片段。挑取38个含有插入片段的阳性克隆测序分析,获得35个已知基因序列和3个未知基因。通过生物信息学分析获得其全长序列,其功能正在研究中。结论应用SSH技术成功构建了HCVE2反式调节基因差异表达的cDNA消减文库。该文库的建立为进一步阐明HCVE2反式调节的靶基因及致慢性肝脏疾病发生的分子生物学机制提供理论依据。     

乙型肝炎病毒X蛋白反式激活基因克隆化的研究

目的 应用抑制性消减杂交（SSH）技术构建乙型肝炎病毒X蛋白（HBX）反式激活基因差异表达的cDNA消减文库，克隆HBX反式激活相关基因。方法 以HBX表达质粒pcDNA3.1(-)-X转染HepG2细胞，以空载体pcDNA3.1(-)转染的HepG2细胞为对照。制备转染后的细胞裂解液，提取mRNA并逆转录为cDNA，经RsaⅠ酶切后，将实验组cDNA分成两组。分别与两组不同的接头衔接，再对照组cDNA进行两次消减杂交及两次抑制聚合酶链反应（PCR），将产物与T/A载体连接，构建cDNA消减文库，并转染大肠杆菌进行文库扩增，随机挑选克隆PCR扩增后进行测序及同源性分析。结果 成功构建人HBX反式激活基因差异表达的cDNA消减文库；文库扩增后得到85个白色克隆，进行菌落PCR分析。均得以200-1000bp插入片段，挑取含有插入片段的65个克隆进行测序，并通过生物信息学分析获得19种已知基因序列。和15个未知基因。结论 应用SSH技术成功构建了HBX反式激活基因差异表达的cDNA消减文库，该文库的建立为进一步阐明HBX反式调节的靶基因及致肝细胞癌发生的分子生物学机制提供理论依据。     

截短型HBsAg中蛋白反式激活基因的克隆

目的：应用抑制性消减杂交技术构建乙型肝炎病毒（HBV）截短型中蛋白（MHBs^t)反式 激活基因差异表达的cDNA消减文库，克隆HBV截短型中蛋白反式激活相关基因。方法：以HBV截短型中蛋白表面质粒pcDNA3.1(-)-Tt167转染HepG2细胞，以空载体pcDNA3.1(-）为对照；制备转染后的细胞裂解液，提取mRNA并逆转录为cDNA，经Rsa I酶切后，将实验组cDNA分成两组，分别与两种不同的接头衔接，再与对照组cDNA进行两次消减杂交及两次抑制性聚合酶链反应（PCR），将产物与T／A载体连接，构建cDNA消减文库，并转染大肠杆菌进行文库扩增，随机挑选克隆PCR扩增后进行测序及同源性分析。结果：成功构建人HBV截短型中蛋白反式激活基因差异表达的cDNA消减文库。文库扩增后得到94个白色克隆，进行菌落PCR分析，均得到200－800bp插入片段。挑取50个插入片段测序，并通过生物学信息学分析获得其全长基因序列，结果共获得23种编码基因，包括19种已知基因的4种未知基因。结论：筛选到的cDNA全长序列，包括一些与细胞生长调节、免疫应答及肿瘤发生密切相关的蛋白编码基因，因此可能是HBV截短型中蛋白反式激活靶基因。     

应用抑制性消减杂交技术克隆和筛选HBV XTP12蛋白反式激活基因的上调基因

目的 克隆并筛选乙型肝炎病毒(HBV)反式激活基因XTP12的上调基因,了解其可能存在的调节功能.方法 应用抑制性消减杂交技术克隆并筛选XTP12反式激活的新型靶基因.以XTP12表达质粒pcDNA3.1(-)-XTP12转染HepG2细胞,以空载体pcDNA3.1(-)为平行对照,制备转染后的细胞裂解液,提取mRNA并逆转录为cDNA,经Rsa Ⅰ酶切后,将实验组cDNA分成2组,分别与2种不同的接头衔接,再与对照组cDNA进行2次消减杂交及2次抑制性聚合酶链反应(PCR),将产物与pGEM-Teasy载体连接,构建cDNA消减文库,并转染大肠杆菌进行文库扩增,随机挑选克隆PCR扩增后进行测序及同源性分析.结果 成功构建人XTP12反式激活基因差异表达的cDNA消减文库.文库扩增后得到68个阳性克隆,进行菌落PCR分析,均得到200～1000 bp插入片段.随机挑选其中28个插入片段测序,并通过生物信息学分析获得其全长基因序列,结果 共获得28种编码基因,其中26种为已知基因编码蛋白,2种为未知功能的新基因.结论 筛选到的cDNA全长序列,包括一些与细胞牛长调节、物质代谢、免疫及肿瘤等密切相关的蛋白编码基因,推测了XTP12可能存在的调控机制的线索.     

抑制性消减杂交技术克隆和筛选丙型肝炎病毒F蛋白的反式调节基因

目的 构建丙型肝炎病毒（HCV）F蛋白反式激活相关基因差异表达的差异cDNA，克隆HCV-F蛋白反式激活相关基因。方法 以HCV-F表达质粒pcDNA3．1（-）-F转染HepG2细胞，以空载体pcDNA3．1（-）为对照；制备转染后的细胞裂解液，从中提取mRNA并合成cDNA，经RsaI酶切后将实验组cDNA分成两组，分别与两种不同的接头衔接，再与对照组cDNA进行两次消减杂交及两次抑制性聚合酶链反应，将产物与T／A载体连接，构建cDNA消减文库，并转染大肠杆菌进行文库扩增，随机挑选克隆聚合酶链反应后进行测序及同源性分析。结果 成功构建人HcVF蛋白反式激活相关基因差异表达的cDNA。扩增后得到56个200～1000bP插入片段的克隆，随机挑选其中28个插入片段测序，并通过生物信息学分析获得其全长基因序列，结果共获得19种编码基因，其中2个为未知功能的新基因。结论 筛选到的cDNA全长序列，包括一些与细胞生长调节、物质代谢和细胞凋亡密切相关的蛋白编码基因。     

Study of transactivating effect of pre-S2 protein of hepatitis B virus and cloning of genes transactivated by pre-S2 protein with suppression subtractive hybridization

AIM: To investigate the transactivating effect of pre-S2 protein of hepatitis B virus (HBV) and construct a subtractive cDNA library of genes transactivated by pre-S2 protein with suppression subtractive hybridization (SSH) technique, and to pave the way for elucidating the pathogenesis of HBV infection. METHODS: pcDNA3.1(-)-pre-S2 containing pre-S2 region of HBV genome was constructed by routine molecular methods. HepG2 cells were cotransfected with pcDNA3.1 (-)-pre-S2/pSV-lacZ and empty pcDNA3.1(-)/pSV-lacZ. After 48 h, cells were collected and detected for the expression of β-galactosidase (β-gal). SSH and bioinformatics techniques were used, the mRNA of HepG2 cells transfected with pcDNA3.1(-)-pre-S2 and pcDNA3.1(-) empty vector was isolated, respectively, cDNA was synthesized. After digestion with restriction enzyme RsaI, cDNA fragments were obtained. Tester cDNA was then divided into two groups and ligated to the specific adaptor 1 and adaptor 2, respectively. After tester cDNA was hybridized with driver cDNA twice and underwent two times of nested PCR, amplified cDNA fragments were subcloned into pGEM-Teasy vectors to set up the subtractive library. Amplification of the library was carried out with E.coli strain DH5oα. The cDNA was sequenced and analyzed in GenBank with Blast search after PCR. RESULTS: The pre-S2 mRNA could be detected in HepG2 cells transfected with pcDNA3.1(-)-pre-S2 plasmid. The activity of β-gal in HepG2 cells transfected with pcDNA3.1 (-)-pre-S2/pSV-lacZ was 7.0 times higher than that of control plasmid (P<0.01). The subtractive library of genes transactivated by HBV pre-S2 protein was constructed successfully. The amplified library contains 96 positive clones. Colony PCR showed that 86 clones contained 200-1 000 bp inserts. Sequence analysis was performed in 50 clones randomly, and the full length sequences were obtained with bioinformatics method and searched for homologous DNA sequence from GenBank, altogether 25 coding sequences were obtained, these cDNA sequences might be the target genes transactivated by pre-S2 protein. CONCLUSION: The pre-S2 protein of HBV has transactivating effect on SV40 early promoter. The obtained sequences may be target genes transactivated by pre-S2 protein among which some genes coding proteins involved in cell cycle regulation, metabolism, immunity, signal transduction and cell apoptosis.This finding brings some new clues for studying the biological functions of pre-S2 protein and further understanding of HBV hepatocarcinogesis.     

Transactivating effect of hepatitis C virus core protein： A suppression subtractive hybridization study

AIM: To investigate the transactivating effect of hepatitis C virus (HCV) core protein and to screen genes transactivated by HCV core protein. METHODS: pcDNA3.1(-)-core containing full-length HCV core gene was constructed by insertion of HCV core gene into EcoRI/BarnHI site. HepG2 cells were cotransfected with pcDNA3.1(-)-core and pSV-lacZ. After 48 h, cells were collected and detected for the expression of β-gal by an enzyme-linked immunosorbent assay (ELISA) kit. HepG2 cell swere transiently transfected with pcDNA3.1(-)-core using Upofectamine reagent. Cells were collected and total mRNA was isolated. A subtracted cDNA library was generated and constructed into a pGEM-Teasy vector. The library was amplified with E. coil strain JM109. The cDNAs were sequenced and analyzed in GenBank with BLAST search after polymerase chain reaction (PCR). RESULTS: The core mRNA and protein could be detected in HepG2 cell lysate which was transfected by the pcDNA3.1(-)-core. The activity of β-galactosidase in HepG2 cells transfected by the pcDNA3.1(-)-core was 5.4 times higher than that of HepG2 cells transfected by control plasmid. The subtractive library of genes transactivated by HCV core protein was constructed successfully. The amplified library contained 233 positive clones. Colony PCR showed that 213 clones contained 100-1 000 bp inserts. Sequence analysis was performed in 63 clones. Six of the sequences were unknown genes. The full length sequences were obtained with bioinformatics method, accepted by Genl3ank. It was suggested that six novel cDNA sequences might be target genes transactivated by HCV core protein. CONCLUSION: The core protein of HCV has transactivating effects on SV40 early promoter/enhancer. A total of 63 clones from cDNA library were randomly chosen and sequenced. Using the BLAST program at the National Center for Biotechnology Information, six of the sequences were unknown genes. The other 57 sequences were highly similar to known genes.     

Screening and cloning for proteins transactivated by the PS1TP5 protein of hepatitis B virus： A suppression subtractive hybridization study

AIM:To clone and identify human genes transactivated by PS1TP5 by constructing a cDNA subtractive library with suppression subtractive hybridization(SSH)technique.METHODS:SSH and bioinformatics techniques were used for screening and cloning of the target genes transactivated by PS1TP5 protein.The mRNA was isolated from HepG2 cells transfected with pcDNA3.1(-)-myc-his(A)-PS1TP5 and pcDNA3.1(-)-myc-his(A)empty vector,respectively,and SSH technique was employed to analyze the differentially expressed DNA sequence between the two groups.After digestion with restriction enzyme RsaⅠ,small size cDNAs were obtained.Then tester cDNA was divided into two groups and ligated to the specific adaptor 1 and adaptor 2,respectively.The tester cDNA was hybridized with driver cDNA twice and subjected to nested PCR for two times,and then subcloned into T/A plasmid vectors to set up the subtractive library.Amplification of the library was carried out with E.coli strain DH5α.The cDNA was sequenced and analyzed in GenBank with Vector NTI 9.1 and NCBI BLAST software after PCR amplification.RESULTS:The subtractive library of genes transactivated by PS1TP5 was constructed successfully.The amplified library contained 90 positive clones.Colony PCR showed that 70 clones contained 200-1000-bp inserts.Sequence analysis was performed in 30 clones randomly,and the full-length sequences were obtained by bioinformatics technique.Altogether 24 coding sequences were obtained,which consisted of 23 known and 1 unknown.One novel gene with unknown functions was found and named as PS1TP5TP1 after being electronically spliced,and deposited in GenBank(accession number:DQ487761).CONCLUSION:PS1TP5 is closely correlated with immunoregulation,carbohydrate metabolism,signal transduction,formation mechanism of hepatic fibrosis,and occurrence and development of tumor.Understanding PS1TP5 transactive proteins may help to bring some new clues for further studying the biological functions of pre-S1 protein.     

丙型肝炎病毒非结构蛋白NS5A反式激活基因NS5ATP9的克隆化研究

目的 筛选并克隆丙型肝炎病毒(HCV)非结构蛋白5A(NS5A)反式激活新型靶基因，研究HCV NS5A反式激活作用的分子生物学机制。方法 应用抑制性消减杂交技术(SSH)及生物信息学技术，以HCV NS5A表达质粒pcDNA3．1(-)-NS5A转染HepG2细胞，以空载体pcDNA3．1(-)为平行对照，提取mRNA并进行抑制性消减杂交分析。对于所获基因片段序列分析表明，其中之一为新型基因片段，与GenBank中注册的已知功能基因序列没有同源性，利用表达序列标签(EST)序列数据库的搜索和比对，进行电子拼接，根据基因起始密码子的Kozak规则和终止密码子下游保守的多聚腺苷酸信号序列，确定新型基因序列。从HepG2细胞提取总RNA，以逆转录多聚酶链反应(RT-PCR)技术扩增获得该新基因的全长序列，并测序证实，命名为NS5ATP9，在GenBank中注册，注册号为AF529370。结果 Ns5ATP9基因的编码序列全长为336个核苷酸(nt)，编码产物由111个氨基酸残基(aa)组成，并成功的克隆化。结论 HCVNS5A反式激活新型靶基因NS5ATP9的筛选与克隆，为进一步研究HcvNs5A反式激活作用的分子生物学机制开辟了新的研究方向。