副黏病毒Tianjin株NP蛋白的稳定表达及其检测

目的:构建副黏病毒Tianjin株NP基因的真核表达载体,转染HEK293细胞,经G418筛选出稳定表达NP蛋白的细胞.方法:应用RT-PCR技术克隆副黏病毒Tianjin株NP基因,插入真核表达载体pcDNA3.1(+).经PCR、酶切和测序鉴定后,将构建的pcDNA3.1(+)-NP用LipofectaminenTM2000转染试剂转染HEK293细胞.应用免疫荧光法及Western Blot检测NP蛋白的瞬时和稳定表达.结果:RT-PCR扩增得到NP基因,重组质粒pcDNA3.1(+)-NP转染HEK293细胞后,经免疫荧光法检测到目的蛋白的瞬时和稳定表达.Western Blot法可见NP蛋白瞬时和稳定表达的条带.结论:副黏病毒Tianjin株NP基因在HEK293细胞可以瞬时和稳定表达,为研究副黏病毒Tianjin株NP蛋白功能与病毒致病性、宿主亲嗜性奠定了基础.     

人白细胞介素24真核表达载体的构建及其在HepG2细胞中的表达

目的 构建人白细胞介素24(human interleukin-24,hIL-24)真核表达载体,并在HepG2细胞中稳定表达,为进一步研究其抗肿瘤作用奠定基础.方法 采用逆转录聚合酶链反应(RT-PCR),从植物血凝素活化的人外周血单个核细胞中克隆得到hIL-24基因目的 片段.应用DNA重组技术将IL-24PCR产物双酶切后定向克隆至真核表达载体pcDNA3.1(+),转化大肠杆菌DHSα获得重组载体,进行PCR、酶切及测序鉴定.应用脂质体将鉴定正确的重组质粒转染至HepG2细胞,用G418筛选稳定转染细胞株.采用RT-PCR检测稳定转染细胞HepG2中IL-24 mRNA的表达.结果 通过RT-PCR获得与预期大小一致约600 bp的IL-24基因片段;重组载体pcDNA3.1(+)-IL-24经PCR、双酶切及测序证实,IL-24 eDNA片段已正确插入真核表达载体中;在稳定转染的HepG2细胞株中可见到IL-24 mRNA表达.结论 成功构建了hIL-24真核表达载体pcDNA3.1(+)-IL-24,并获得了稳定转染该重组质粒的HepG2细胞株.     

MCHR2在CHO细胞中的稳定表达及其信号通路分析

目的构建人MCHR2基因真核表达载体,在CHO细胞中进行稳定表达,并分析MCHR2介导的信号转导通路。方法采用PCR方法,以人胎脑cDNA文库为模板扩增人MCHR2基因的全长cDNA编码区序列,定向插入到真核表达载体pcDNA3·1(+),经酶切和测序鉴定后,脂质体转染法转染CHO细胞,通过G418选择培养,建立稳定转染细胞系,经RT-PCR和Western blot鉴定后,通过测定细胞内cAMP、Ca2+浓度的改变分析MCHR2的信号转导通路。结果成功构建了pcDNA3·1-MCHR2真核表达载体并稳定转入CHO细胞,建立了稳定转染细胞系,成功地表达目的基因,MCH作用于MCHR2后不影响细胞内cAMP生成,可促使细胞内钙库释放Ca2+,进而使胞内Ca2+浓度出现明显而短暂的升高,提示MCHR2的信号转导通路主要是与Gq蛋白偶联。结论人MCHR2的稳定表达和信号转导通路分析为进一步体外研究MCHR2的功能提供了良好的实验基础。     

Id1 miRNA表达载体构建与转染乳腺癌细胞

目的构建正义、反义Id1真核表达载体,并成功转染乳腺癌MDA．MB-231细胞系,筛选稳定表达细胞株。方法设计针对Id1基因的mRNA效的干扰序列。将干扰序列插入pcDNA6．2-GW／EmGFP-miR表达载体,构建Id1 miRNA真核表达载体,脂质体转染法转染乳腺癌MDA-MB-231细胞系,杀稻瘟霉素筛选稳定表达的细胞株。结果Id1 mRNA真核表达载体的构建后,经酶切及测序鉴定正确后。转染乳腺癌MDA-MB231细胞系。经过2周杀稻瘟霉素筛选,获得稳定表达的细胞系。经RT-PCR鉴定,转染Id1 mRNA真核表达载体的细胞系M1表达水平低于对照组。未转染组与阴性对照转染组无明显差异。     

MDM2基因真核表达质粒构建及对人乳腺癌MCF-7细胞运动与侵袭能力的影响

目的 构建MDM2的pcDNA3.1真核表达质粒(pcDNA3.1-MDM2),并将其转染至人乳腺癌MCF-7中,考察MDM2蛋白过表达对乳腺癌转移的影响。方法 采用PCR方法体外克隆MDM2基因全序列,并将其用同源重组技术连接到真核pcDNA3.1质粒载体上,构建真核表达质粒,并进行测序鉴定,利用脂质体法转染至MCF-7细胞中。通过G418抗生素筛选出单克隆高表达细胞系,使用免疫印迹法考察MDM2蛋白表达。同时,通过划痕试验及transwell法来检测细胞的运动与侵袭能力。结果 测序结果表明pcDNA3.1-MDM2基因序列准确无误,免疫印迹法表明稳定转染细胞系构建成功,划痕试验及transwell试验表明MDM2高表达细胞系的运动与侵袭能力增加。结论 成功构建了pcDNA3.1-MDM2真核表达质粒,转染MCF-7细胞后,可稳定表达,并促进了MCF-7细胞的运动及侵袭,为研究MDM2蛋白表达对人乳腺癌转移的分子机制及作为诊疗的生物标志物奠定了基础。     

HCV-F基因在hepG2细胞中的表达以及对PI3K的影响

探讨丙型肝炎病毒(HCV)F基因对PI3K表达的影响.应用PCR技术从含有HCV全长开放阅读框的质粒中获得HCV-F基因片段,利用基因重组技术将其克隆至真核表达载体pcDNA3.0(-)中.通过酶切、PCR及测序鉴定,HCV-F基因已正确插入到pcDNA3.0(-)中,再利用脂质体转染HepG2细胞.经RT-PCR及Western blot检测,HCV的F基因在HepG2细胞中获得表达,而且在表达重组HCV-F的转染HepG2细胞中,检测到PI3K蛋白的表达.实验表明HCV-F可在体外激活PI3K及其信号通路.     

ASAP3真核表达载体的构建和鉴定

目的:构建ASAP3的真核表达载体并鉴定。方法:通过DNA重组技术和PCR方法从人肝癌细胞株HepG2克隆ASAP3基因,插入真核表达载体pcDNA3.1(+)中,通过PCR、酶切及测序鉴定重组载体的正确性。结果:DNA测序和酶切鉴定证明ASAP3基因正确克隆至pcDNA3.1(+)的多克隆位点。结论:成功构建ASAP3的真核表达载体p ASAP3。     

抑制性消减杂交技术筛选干扰素α转染HepG2细胞中上调的表达基因

目的:应用抑制性消减杂交(suppression subtractive hybridization,SSH)技术筛选干扰素α(IFN-α) 真核表达质粒转染HepG2细胞后差异表达上调的基因。方法:首先构建IFN-α真核表达载体pcDNA3．1(-) -IFN-α,并转染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次抑制多聚酶链反应(PCR),将产物与T／A载体连接,构建cDNA消减文库,并转化大肠杆菌进行文库扩增,随机挑选克隆PCR扩增鉴定,进行测序及同源性分析。结果:构建了pcDNA3．1(-)-IFN-α真核表达质粒,并成功构建了该质粒转染HepG2细胞后差异表达基因的cDNA消减文库。文库扩增后得到200个白色克隆,随机挑取70个进行菌落PCR分析,结果显示均含有插入片段,将含有200-1000 bp插入片段的35个克隆进行测序,并通过生物信息学分析获得17种已知基因序列和1个染色体序列。结论:应用SSH技术成功构建了pcDNA3．1(-)-IFN-α转染的HepG2细胞中差异上调表达基因的cDNA消减文库。该文库的建立为进一步阐明IFN-α作用的分子生物学机制提供了重要的理论依据。     

Claudin-1荧光真核表达载体的构建及其在HepG2肝癌细胞中的表达

目的构建pDsRED1-Claudin-1重组质粒,并在HepG2肝癌细胞中进行表达。方法采用基因重组技术构建含Claudin-1开放读码框(ORF)基因的红色荧光蛋白报告基因载体pDsRED1-Claudin-1。经PCR、酶切和DNA测序鉴定,通过脂质体法转染HepG2肝癌细胞后,进行荧光检测和Western blot分析。结果成功构建真核表达质粒pDsRED1-Claudin-1,转染HepG2细胞后,经荧光检测和Western blot分析可见Claudin-1红色荧光融合蛋白正确表达。结论成功构建含Claudin-1 ORF基因的红色荧光蛋白报告载体,并在HepG2肝癌细胞中正确表达。     

肾脏花生四烯酸CYP羟化酶参与高血压的形成及维持正常血压的稳定

目的:研究肾脏特异性表达CYP4A1与血压变化的关系.方法:将含有开放阅读框的CYP4A1 cDNA克隆到真核表达载体pcDNA3.1,构建4Al/pcDNA3.1和反义4Al/pcDNA3.1重组体,舌下静脉注射转染SD雄性大鼠,经尾动脉测量收缩压.用Western blot及Northern blot分析转染对照pcDNA3.1质粒及正、反义CYP4A1重组体后,CYP4A1在大鼠的脑、心、肺、肝、肾组织表达水平.结果:转染正义、反义CYP4A1两周后,大鼠的血压与对照组相比分别增加1.8kPa±0.3kPa(13.2mmHg±2.5mmHg)和减少了1.7kPa±0.3kPa(13.0mmHg±2.2 mmHg).Western blot及Northern blot结果均显示CYP4A1可选择性地在肾脏表达,而在脑、心、肺、肝几乎无表达,且在给予反义CYP4A1的大鼠肾脏中CYP4Al蛋白表达几乎被完全阻断.结论:在正常的SD大鼠肾脏中,转染正、反义CYP4A1可引起血压升高和降低,说明肾脏花生四烯酸CYP羟化酶参与高血压的形成及维持正常血压的稳定.     

Identification and functional characterization of new potentially defective alleles of human CYP2C19

CYP2C19 is a clinically important enzyme responsible for the metabolism of a number of therapeutic drugs, such as mephenytoin, omeprazole, diazepam, proguanil, propranolol and certain antidepressants. Genetic polymorphisms in this enzyme result in poor metabolizers of these drugs. There are racial differences in the incidence of the poor metabolizer trait, which represents 13-23% of Asians but only 3-5% of Caucasians. In this study, single nucleotide polymorphisms (SNPs) in CYP2C19 were identified by direct sequencing of genomic DNA from 92 individuals from three different racial groups of varied ethnic background, including Caucasians, Asians and blacks. Several new alleles were identified containing the coding changes Arg114 His (CYP2C19*9), Pro227 Leu (CYP2C19*10), Arg150 His (CYP2C19*11), stop491 Cys (CYP2C19*12), Arg410 Cys (CYP2C19*13), Leu17 Pro (CYP2C19*14) and Ile19 Leu (CYP2C19*15). When expressed in a bacterial cDNA expression system, CYP2C19*9 exhibited a modest decrease in the V(max) for 4'-hydroxylation of -mephenytoin, and no alteration in its affinity for reductase. CYP2C19*10 exhibited a dramatically higher K(m) and lower V(max) for mephenytoin. CYP2C19*12was unstable and expressed poorly in a bacterial cDNA expression system. Clinical studies will be required to confirm whether this allele is defective in vivo. CYP2C19*9, CYP2C19*10 and CYP2C19*12 all occurred in African-Americans, or individuals of African descent, and represent new potentially defective alleles of CYP2C19 which are predicted to alter risk of these populations to clinically important drugs.     

Allele and genotype frequency of CYP2C19 in a Tamilian population

AIMS: To investigate the frequencies of CYP2C19*1, CYP2C19*2 and CYP2C19*3 alleles and CYP2C19 genotypes in a Tamilian population. METHODS: The study was conducted in 112 unrelated healthy human volunteers. DNA was extracted from leucocytes and analyzed by the PCR-RFLP protocol. The PCR product was digested with restriction enzymes (SmaI and BamH1) and then separated electrophoretically using polyacrylamide gel. RESULTS: The frequencies of the CYP2C19*1, *2 and *3 alleles were 0.598 [95% confidence interval (CI) 0.507, 0.689], 0.379 (95% CI, 0.350,0.407) and 0.022 (95% CI -0.005, 0.049), respectively. The distribution of CYP2C19*1/*1,*1/*2, *1/*3, *2/*2 and *2/*3 genotypes were 0.295 (95% CI, 0.210, 0.379), 0.580 (95% CI, 0.488, 0.671), 0.027 (95% CI -0.003, 0.057), 0.080 (95% CI 0.030, 0.130) and 0.018 (95% CI -0.006, 0.042), respectively. CONCLUSIONS: The distribution of CYP2C19*1/*1 in the Tamilian population is lower than that in Caucasians, Africans and the North Indian population. The CYP2C19*1/*2 is significantly higher in Tamilians when compared with other populations. The CYP2C19*1/*3 allele, which was not reported in the North Indian and Caucasian populations has been identified in 2.7% of the Tamilian population.     

中国汉族癫痫患者CYP2C19和CYP2C9基因多态性对苯妥英钠血药浓度的影响

目的 研究中国汉族癫痫患者细胞色素P450(CYP450)2C19和2C9基因多态性对苯妥英钠血药浓度的影响.方法 用PCR-RFLP方法,分析82例患者的CYP2C19*2,*3及CYP2C9*3这3个单碱基突变位点,用荧光偏振免疫法(FPIA)测定苯妥英钠血药浓度.结果 CYP2C9*3*、CYP2C19*2及CYP2C19*3等位基因频率分别为7.3%,33.5%和3.7%.强、中间、弱代谢组间的标准化血药浓度差别显著(P=0.000).苯妥英钠血药浓度的多元线性回归中,CYP2C19*2、CYP2C19*3、CYP2C9*3这3个基因突变位点beta值分别为5.71,6.65,6.95.结论 基因突变导致苯妥英钠血药浓度升高,且与突变位点的数量有关.     

Enzyme activity analysis of CYP2C18 with exon 5 skipped

AIM: To study the enzyme activity of CYP2C18 variant with exon 5 skipped. METHODS: A full length CYP2C18 cDNA X1 and an exon 5 skipped variant CYP2C18 X2 were separately subcloned into mammalian expression vector pREP9 to transfect HepG2 cells. The expression of CYP2C18 mRNA in transgenic cells and human liver tissues were determined by RT-PCR. The enzyme activity of CYP2C18 to oxidate tolbutamide in postmitochondrial supernate (S9) fraction was determined by HPLC. The cytotoxicity of ifosfamide to transgenic cells was evaluated by MTT test. RESULTS: HepG2-CYP2C18 X1 cells showed strong expression of the full length CYP2C18 mRNA. On the other hand, HepG2-CYP2C18 X2 cells had only infinitesimal expression of the exon-skipped CYP2C18 as well as the full length CYP2C18, while non-transfected HepG2 cell only demonstrated an infinitesimal expression of the full length CYP2C18. The expression of CYP2C18 exons 2 to 7 was also analyzed by RT-PCR in 7 extratumoral liver tissues. Among them, 3 samples expressed on     

Polymorphisms of CYP2C19 and CYP2D6 in Israeli Ethnic Groups

BACKGROUND: The cytochrome P450 isoenzymes CYP2C19 and CYP2D6 catalyze reactions involved in the metabolism of many widely used drugs. Their polymorphisms give rise to important interindividual and interethnic variability in the metabolism and disposition of several therapeutic agents and may cause differences in clinical response to some drugs. Individuals who carry two null alleles of either gene are known as poor metabolizers (PMs), while those who carry more than two copies of the functional CYP2D6 gene are ultrarapid metabolizers (UMs). AIM: The aim of the current study was to genotype Israelis from four different ethnic backgrounds with respect to CYP2C19 and CYP2D6. STUDY DESIGN: Polymorphisms of the CYP2C19 and CYP2D6 genes were determined by genotyping the four ethnic groups using PCR and/or restriction fragment length polymorphism (RFLP) analysis. The groups consisted of three Jewish communities, Yemenite Jews (n = 36), Sephardic Jews (n = 47), Ethiopian Jews (n = 28), and one Arabian population, Bedouins (n = 50). RESULTS: CYP2C19*2 allele frequencies ranged from 12.0 to 19.6% among the four ethnic groups. Within the study population, the CYP2C19*3 gene was only found in one Bedouin individual, in the heterozygous state (CYP2C19*1/*3). In each group, one individual was homozygous for CYP2C19*2, and were predicted to be PMs. The data revealed a high prevalence of CYP2D6*2, *4, *10, *41, and gene duplication, followed by *5 and *17, while *3 was very rare. The frequencies of the CYP2D6*4, *10, and *17 alleles and CYP2D6 gene duplication were significantly different among the four groups. However, the CYP2D6*2, *3, and *5 and *41 alleles showed similar frequencies in the four groups. Four (8.5%) Sephardic Jews and one (2.0%) Bedouin were found with the genotype CYP2D6*4/*4 (two null alleles), and were thus presumably PMs. A total of 15 individuals, distributed in all groups, were found with functional CYP2D6 gene duplications. The frequencies of predicted UMs (duplication of CYP2D6) were 17.8% (5/28) and 12.8% (6/47) in Ethiopian Jews and Sephardic Jews, respectively, which were higher than that of Yemenite Jews (5.6%, 2/36) and Bedouins (4.0%, 2/50). CONCLUSIONS: This is the first study of the CYP2D6 gene polymorphism in Israeli ethnic groups, either Jewish or Arab. Furthermore, this is also the first study of the CYP2C19 gene polymorphism in Jewish or Arab subgroups living in Israel. The frequencies of various alleles for the CYP2D6 gene are significantly different among the ethnic groups in Israel. These new findings may have important clinical implications in administrating drugs metabolized by CYP2D6 and for CYP2D6-related adverse drug reactions in the Israeli population.     

Genetic polymorphisms of CYP2C9 and CYP2C19 in the Beninese and Belgian populations

AIMS: To investigate the distribution of cytochrome P450 2C9 (CYP2C9) and 2C19 (CYP2C19) genotype frequencies in the Beninese and Belgian Caucasian populations. METHODS: Beninese (n = 111) and Belgian (n = 121) were genotyped for CYP2C9*2, *3, *4, *5, and *11 as well as for CYP2C19*2 and*3. RESULTS: The distribution of alleles was: CYP2C9*1: 95.5 vs. 82.2% (P < 0.001); CYP2C9*2: 0 vs. 10% (P < 0.001); CYP2C9*3: 0 vs. 7.4% (P < 0.01); CYP2C9*4: both 0%; CYP2C9*5: 1.8 vs. 0% (P = 0.05); and CYP2C9*11: 2.7 vs. 0.4% (P < 0.05). The frequencies of the CYP2C19*2 allele were 13 vs. 9.1%, respectively. CYP2C19*3 was not detected in either population. The 95% confidence intervals for the differences of frequencies of CYP2C9*1, CYP2C9*2, CYP2C9*3, CYP2C9*4, CYP2C9*5, CYP2C9*11, CYP2C19*1, CYP2C19*2 and CYP2C19*3 between Belgian and Beninese were 7%, 19%; - 14%, - 6%; - 11%, - 4%; - 1%, 1%; 0%, 4%; 0%, 5%; - 10%, 2%; - 2%, 10%; - 1%; respectively. The distributions of CYP2C9 genotypes in the Beninese and Belgian individuals were: CYP2C9*1/*1: 91 vs. 67% (P < 0.00001); CYP2C9*1/*2: 0 vs. 18.2% (P < 0.0001); CYP2C9*1/*3: 0 vs. 11.6% (P < 0.001); CYP2C9*1/*5: 3.6 vs. 0% (P = 0.05); CYP2C9*1/*11: 5.4 vs. 0.8% (P = 0.05); CYP2C9*2/*3: 0 vs. 1.6% (NS); CYP2C9*3/*3: 0 vs. 0.8% (NS). The distributions of CYP2C19 genotypes between these ethnic groups were: CYP2C19*1/*1: 73.9 vs. 83.5% (NS); CYP2C19*1/*2: 26.1 vs. 14.9% (P < 0.05); CYP2C9*2/*2: 0 vs. 1.6% (NS). CONCLUSIONS: Differences of allele frequencies between Beninese and Belgian populations were statistically significant for CYP2C9*2, *3, *5 and *11, but not for CYP2C9*4 or for CYP2C19*2 and *3.     

Allele and genotype frequencies of CYP2C9 in a Korean population

AIMS: To determine the frequencies of the variant alleles and the genotypes of CYP2C9 in a Korean population. METHODS: Three hundred and fifty-eight healthy Korean subjects were studied. CYP2C9 alleles were detected by polymerase chain reaction-restriction fragment length polymorphism assays and direct sequencing assays. RESULTS: The allele frequencies were 0.934 for CYP2C9*1, 0.060 for CYP2C9*3 and 0.006 for CYP2C9*13. The CYP2C9*2,*4,*5 and *11 alleles were not detected. The frequencies of the CYP2C9*1/*1, *1/*3 and *1/*13 genotypes were 0.869, 0.120 and 0.011, respectively. CONCLUSION: The frequency of the CYP2C9*3 allele in the Korean population studied was significantly higher than reported elsewhere, and a novel allele, CYP2C9*13, was found at a frequency of 0.006 (95% confidence interval 0, 0.012). Only three genotypes of CYP2C9, CYP2C9*1/*1,*1/*3 and *1/*13 were observed in this Korean population.