CUL5基因的RNA干扰真核表达载体的构建

目的：构建CUL5基因的RNA干扰真核表达载体,探索CUL5在鼻咽癌放射治疗中加速再增殖的作用。方法：根据GenBank数据库提供的CUL5基因mRNA序列,按照Tuschl设计原则,设计选择双链小干扰RNA（small interfering RNA,siRNA）,再设计合成为能表达其小发卡结构RNA（small hairpin RNAs,shRNA）的DNA序列,并与pGPU6／GFP／Neo质粒定向连接,构建真核表达载体,并进行限制性内切酶酶切和DNA测序鉴定。结果：经限制性内切酶酶切和DNA测序证实质粒中插入的为所需序列,通过RT—PCR证实其能够干扰CNE2细胞的CUL5基因表达。结论：CUL5基因RNA干扰真核细胞表达载体的构建成功。     

稳定沉默CUL5基因的CNE2细胞系建立

目的:建立稳定沉默CUL5基因的CNE2细胞系,探讨CUL5在连续分割照射下鼻咽癌细胞加速再增殖现象中所起的作用.方法:设计并合成能表达针对CUL5基因的shRNA的DNA序列,构建真核表达载体;脂质体转染重组质粒至人鼻咽癌细胞株CNE2;G418筛选阳性细胞并扩大培养;RT-PCR检测连续分割照射前后阳性细胞CUL5基因沉默效果.结果:经限制性内切酶酶切和DNA测序证实质粒中插入的为所需序列;G418筛选所得阳性细胞经RT-PCR证实照射前后均能抑制 CUL5基因表达.结论:成功建立CUL5基因沉默的CNE2细胞系.     

Survivin特异性siRNA真核表达载体的构建

目的构建Survivin特异性siRNA真核表达载体，为以Survivin基因为靶点、小干扰RNA（small interfering RNA，siRNA）为手段的白血病和其它恶性肿瘤基因治疗的基础和临床应用提供良好的技术手段。方法根据GeneBank数据库提供的Survivin基因所有变异体的共同核苷酸序列，按照Tuschl设计原则，选择设计双链siRNA，再转化为能表达其小发卡结构RNA（small hairpin RNA，shRNA）的DNA序列，并与载体pSINsi-hU6定向连接，构建受控于启动子u6的真核表达载体pSIN／shRNA1、pSIN／shR-NA2，经限制性内切酶酶切和DNA测序进行鉴定。结果构建Survivin特异性siRNA真核表达载体pSIN／shRNA1、pSIN／shRNA2，经限制性内切酶酶切和DNA测序证实与设计完全一致。结论Survivin特异性siRNA真核表达载体构建成功。     

VEGF-C基因RNA干扰真核表达载体的构建及其效果鉴定

目的:构建VEGF-C基因RNA干扰(RNAi)的真核细胞表达载体。方法:以VEGF-C为靶基因,以pGenSil-l质粒为载体,设计构建重组体,根据GenBank数据库提供的VEGF-C基因核苷酸序列,按照Tuschl设计原则,选择设计两条带发夹结构的核苷酸序列,克隆到空载体pGenSil-l中,转化DH5α菌株,提取质粒,进行限制性内切酶酶切鉴定和测序分析,将重组的pGenSil-VEGF-C质粒转染LOVO细胞48小时,检测其对LOVO细胞VEGF-C蛋白与mRNA表达的影响。结果:经酶切鉴定筛选出的重组体测序结果与目的序列完全一致,重组载体显著降低Lovo细胞VEGF-C的蛋白和mRNA表达,重组载体构建成功。结论:利用RNAi技术可成功构建抑制VEGF-C表达的小干扰RNA重组体。     

VEGF-C基因RNA干扰真核表达载体的构建及其效果鉴定

目的：构建VEGF-C基因RNA干扰（RNAi）的真核细胞表达载体。方法：以VEGF-C为靶基因,以pGenSil-1质粒为载体,设计构建重组体,根据GenBank数据库提供的VEGF-C基因核苷酸序列,按照Tuschl设计原则,选择设计两条带发夹结构的核苷酸序列,克隆到空载体pGenSil-1中,转化DH5α菌株,提取质粒,进行限制性内切酶酶切鉴定和测序分析,将重组的pGenSil-VEGF-C质粒转染LOVO细胞48小时,检测其对LOVO细胞VEGF-C蛋白与mRNA表达的影响。结果：经酶切鉴定筛选出的重组体测序结果与目的序列完全一致,重组载体显著降低Lovo细胞VEGF-C的蛋白和mRNA表达,重组载体构建成功。结论：利用RNAi技术可成功构建抑制VEGF-C表达的小干扰RNA重组体。     

CtBP1基因shRNA真核表达载体的构建及其干扰效果的初步鉴定

目的：构建C-末端结合蛋白-1（CtBP1）基因RNA干扰（RNAi）的真核表达载体,转染人子宫内膜癌耐药细胞株B-MD-C1（ADR＋/＋）,初步鉴定其干扰效果。方法：以人CtBP1基因为靶基因,以pGenesil-1质粒为载体,根据GenBank数据库提供的CtBP1基因核苷酸序列,选择设计两条siRNA干扰序列,将带9个碱基茎环结构的干扰序列插入带有绿色荧光蛋白（EGFP）基因、卡那霉素（Kanr）抗性基因及U6启动子的真核表达载体pGenesil-1中,构建针对CtBP1基因的shRNA真核表达载体,转化大肠杆菌DH5α菌株,提取质粒,进行限制性内切酶酶切鉴定和测序分析。确认载体构建成功后,用脂质体LipofectamineTM2000将重组质粒瞬时转染人子宫内膜癌耐药细胞株B-MD-C1（ADR＋/＋）,在荧光显微镜下观察绿色荧光蛋白表达,计数转染细胞数,计算转染效率,RT-PCR法检测载体对CtBP1基因的表达抑制效果。结果：构建针对CtBP1基因的pGenesil-1-CtBP1小发夹RNA（pGenesil-1-CtBP1-shRNA）,经限制性内切酶酶切、PCR和DNA测序证实与设计完全一致;在荧光显微镜下观察到B-MD-C1（ADR＋/＋）细胞表达绿色荧光蛋白（EGFP）,证实重组质粒己转染入细胞,转染效率达到60%-70%;RT-PCR结果显示B-MD-C1（ADR＋/＋）细胞中CtBP1基因被特异抑制,基因表达抑制率达40%以上,与转染试剂对照组、空白对照组和阴性序列对照组间的差异均具有统计学意义（P均〈0.05）。结论：成功构建CtBP1基因的shRNA表达载体,可以有效抑制B-MD-C1（ADR＋/＋）细胞上CtBP1基因表达。为进一步研究CtBP1基因功能进而逆转肿瘤的多药耐药奠定基础。     

survivin基因RNAi逆转录病毒载体设计与构建方法实验研究

目的　设计和构建survivin基因的表达si RNA逆转录病毒重组载体,探讨胶质瘤分子病因及用于基因治疗的可行性。方法　利用在线软件si Direct设计干扰survivin基因靶序列,合成回文DNA序列退火后克隆至线性化p SUPER质粒载体,重组质粒载体双酶切电泳鉴定和测序分析,再转染phoenix细胞产生病毒转染低分化SHG4 4 - 9胶质瘤细胞株。利用NIH3T3细胞测定病毒滴度。Western blot测定转染后SHG4 4 - 9细胞survivin表达量。结果　p SU PER表达si RNA重组质粒载体经双酶切电泳鉴定和DNA测序分析,证实插入6 0 bp序列与原序列一致,位置正确。测定p SUPER.retro- S1、p SU PER.retro- S2病毒滴度值分别为5 .5×10 5CFU/ m l和5 .75×10 5CFU/ ml,干扰效率分别为70 .5 %和接近10 0 .0 %。结论　survivin基因的表达si RNA逆转录病毒重组载体的构建成功,不但为研究胶质瘤分子病因和基因治疗提供了有用工具,而且也为研究高表达survivin的其它肿瘤构建了新的平台。     

E2F3基因腺相关病毒干扰载体的构建

目的:构建针对E2F3基因的腺相关病毒干扰穿梭质粒载体,为进一步包装能够表达干扰序列的病毒奠定基础.方法:通过已经合成的pRNAT-U6.1-siE2F3/Neo干扰质粒载体,进行限制性内切酶Mlu酶切,将干扰片段克隆入线性质粒pAAV-MCS中,构建具有表达沉默E2F3基因的RNA干扰穿梭质粒.通过BglⅡ及Mlu单酶切,BamH1和HandⅢ双酶切、PCR鉴定及基因片段序列分析验证构建是否成功.结果:pAAV-siE2F3线性化后,片段大小约6 300bp;以Mlu为两边酶切位点设计的引物对重组质粒进行PCR,可获得的产物大小1700bp;应用ITR专用引物进行重组质粒的PCR后证实本研究所构建的重组质粒ITR片段存在,大小约3500bp,上述指标均与预期设计结果相符.基因测序结果表明插入序列无基因突变,序列完整.结论:穿梭质粒载体的成功构建,为进一步包装能够表达针对E2F3基因干扰序列的腺相关病毒,进一步研究E2F3基因在肿瘤中的功能奠定基础.     

真核表达载体pEGFP-N1-Ubc9的构建及表达

目的:克隆人类Ubc9基因cDNA全长,构建Ubc9的真核表达载体并表达。方法:采用RT-PCR技术从人小细胞肺癌NCI-H446细胞总RNA中扩增Ubc9 cDNA基因片段,经过酶切鉴定后,克隆至pUCM-T载体,测序证实碱基序列无误后,再克隆至真核绿色荧光蛋白表达载体(pEGFP-N1)上,并转染到真核细胞,观察其在真核细胞中的表达。结果:测序证实克隆的Ubc9全长cDNA阅读框正确完整,酶切和序列测定证实Ubc9正确插入pEGFP-N1载体中,该重组载体能够在真核细胞中表达。结论:成功构建了真核表达载体pEGFP-N1-Ubc9。     

靶向人Pokemon基因的shRNA重组质粒的构建

目的构建靶向Pokemon基因的短发夹RNA（shRNA）真核表达载体,为研究Pokemon基因在肿瘤发生发展中的作用奠定基础。方法利用基因重组技术,依据siRNA的设计原则,针对目的基因的mRNA序列筛选了3对siRNA序列以及一对阴性对照序列,将其分别插入真核表达载体psiRNA-hHlneo H1启动子下游,经α互补筛选、酶切和DNA测序鉴定,构建靶向Pokemon基因的RNAi真核表达载体。结果酶切鉴定及DNA测序结果显示siRNA片断正确,与设计序列一致,且成功插入预定位点。结论靶向Pokemon基因的shRNA重组质粒成功构建,为进一步研究Pokemon基因在多种疾病中的作用以及探索肿瘤的基因治疗奠定基础。     

CD59 RNAi逆转录病毒载体转染卵巢癌细胞株A2780的构建

目的获得携带针对人CD59基因p SUPER retro RNAi逆转录病毒载体的卵巢癌细胞株A2780。方法设计能转录产生靶向CD59小发夹RNA(sh RNA)转染逆转录病毒载体p SUPER retro neo+gfp质粒,构建p SUPER-si CD59重组质粒,将重组质粒导入卵巢癌细胞株A2780内。鉴定转染后细胞株能形成稳定的扩增。结果重组质粒经PCR凝胶电泳、核苷酸测序证实与设计序列一致;重组质粒转染卵巢癌细胞株A2780,可稳定表达绿色荧光蛋白。结论携带针对人CD59基因p SUPER retro RNAi逆转录病毒载体的卵巢癌细胞株A2780的建立为深入进行肿瘤细胞研究奠定了基础。     

肿瘤双自杀基因治疗系统pTRKH2-PsT/CD,pTRKH2-PsT/UPRT在厌氧婴儿双歧杆菌中的构建

Objective: We recombine the suicide gene CD, UPRT into plasmid pTRKH2 and clone the recombinant dual suicide gene therapy system into tumor-hypoxia-targeting vector Bifidobacterium infantis and characterize its function. Methods: CD gene, UPRT gene and lactic acid bacteria expression plasmid pTRKH2 were digested by restriction endonuclease BamH I and Sal I, and constructed recombinant plasmids pTRKH2/CD and pTRKH2/UPRT in E. coll. The recombinant plasmids were then transfected into Bifidobacterium Infantis by electroporation. Identification of pTRKH2/CD and pTRKH2/UPRT was processed by dual restriction endonuclease digesting and sequencing. RT-PCR and SDS-PAGE were used to examine the expression of CD and UPRT genes at RNA and protein levels. The killing effects on Melanoma B16-F10 cells by pTRKH2/CD and pTRKH2/UPRT suicide gene therapy system with 5-FC were examined by MTT assay. Results: The CD gene and UPRT gene was successfully recombined into lactic acid bacteria expression plasmid pTRKH2. After dual endonuclease digestion of plasmid purified from the positively transfected E. co/i, two fragments of 6.9 Kb and 1.3 Kb were found for CD gene and two fragments of 6.9 Kb and 620 bp were found for UPRT gene. The sequencing of CD gene and UPRT gene proved consistent sequences with Genebank published data. A fragment of 1.3 Kb for CD gene and fragment of 620 bp for UPRT gene was found in recombinant Bifidobac- terium by RT-PCR. A 52 KDa protein for CD gene was identified in whole-cell protein of recombinant Bifidobacterium and a 26 KDa protein for UPRT gene was identified in supernatant fluid of recombinant Bifidobacterium. The survival rate of tumor cells treated by extracts from culture of recombinant Bifidobacterium with 5-FC showed a strong killing effects of pTRKH2/CD and pTRKH2/UPRT dual suicide gene therapy system on Melanoma B16-F10 cells. Conclusion: CD gene and UPRT gene are suc- cessfully inserted into pTRKH2 and transfected into tumor-hypoxia-targeting vector Bifldobacterium Infantis. This dual suicide gene therapy system shows a high efficiency for tumor cells killing.     

Survivin基因siRNA真核表达载体的构建及其对转染膀胱癌细胞Survivin表达的抑制作用

目的构建针对Survivin基因的siRNA(smallinterferenceRNA)真核表达载体,并观察其对转染的膀胱癌细胞中Survivin基因表达和细胞凋亡的影响。方法应用siRNA设计软件设计针对Survivin基因的特异性短链寡核甘酸,化学合成后经退火形成双链siRNA模板,通过克隆到质粒pSilencer1.0-U6构建siRNA真核表达载体并用酶切和测序鉴定;然后将其转染人膀胱癌细胞株BIU-87,以反义Survivin寡核甘酸(ASODN)抑制效果为对照,分别采用噻唑蓝(MTT)比色法和DNA原位末端标记(TUNEL)法检测BIU-87细胞生长抑制率(IR)和凋亡指数(AI),半定量逆转录聚合酶链反应(RT-PCR)和Westernblot检测BIU-87细胞中SurvivinmRNA及其蛋白的表达。结果酶切和测序证实siRNA真核表达载体构建成功。siRNA对BIU-87细胞的IR和AI(62.14%和33.77%)均分别显著高于ASODN(39.33%和23.98%)和空白对照组(1.98%和3.75%),P均<0.05,SurvivinmRNA及其蛋白相对表达水平均显著低于ASODN和空白对照组。结论构建的siRNA真核表达载体能有效地抑制Sur-vivinmRNA的转录和表达,诱导BIU-87细胞凋亡和抑制细胞生长,为膀胱肿瘤的基因治疗提供新的方法和手段。     

siRNA 抑制肝癌细胞DNA 修复门控基因表达的实验

 目的 本实验旨在研究siRNA抑制DNA修复门控基因Rad52、Ku70和Ku80的效果并筛选出高效的siRNA作用靶位。方法 依据siRNA设计原则，针对每一个门控基因的mRNA序列各选择了2个靶位点并构建了相应的siRNA表达载体（psiRNA1～6）。酶切分析及DNA测序鉴定重组质粒构建成功后，将其转染人肝癌细胞株HepG2。RT-PCR和WesternBlot分别用来检测psiRNAs在转录水平和翻译水平干扰靶基因的效果。结果 psiRNA1～6作用细胞后明显抑制了靶基因的表达。比较而言，psiRNA1、psiRNA4、psiRNA5干扰效果分别比psiRNA2、psiRNA3、psiRNA6更佳。结论 siRNA为进一步研究DNA修复门控基因Rad52、Ku70和Ku80的功能奠定基础。     

婴儿双歧杆菌/胞嘧啶脱氨酶肿瘤靶向性基因治疗系统的构建

Objective： To construct Bifidobacterium Infantis/CD targeting gene therapy system. Methods： CD gene was amplified from E. Coli K12λ using PCR method, pGEX-1LamdaT plasmid and CD gene were digested with dual restriction endonucleas of EcoR Ⅰ and BamH Ⅰ and two segments of 4.9 kb and 1.3 kb were obtained. T4 DNA ligase was added to these two segments to make a recombinant CD/pGEX-1LamdaT plasmid. Then the recombinant plasmid was transfected into Bifidobacterium Infantis by electroporation. The recombinant plasmid was extracted from the positively transfected Bifidobacterium Infantis and digested with dual restriction endonucleases. Then the size of digested fragments was detected and sequencing of the gene segment inserted in extracted recombinant plasmid was performed according to the method of Sanger dideoxynucleotide triphosphate chain termination. Results： 6.2 kb recombinant plasmid was obtained from the positively transfected bacterial colony of Bifidobacterium Infantis. After being digested with dual restriction endonucleases, two segments of approximate 4.9 kb and 1.3 kb were gained from the extracted recombinant plasmid, which were equal to the size of pGEX-1LamdaT plasmid and CD gene, respectively. The full length and sequence of nucleotide acid of the inserted gene in extracted recombinant plasmid was completely identical to the CD gene. Conclusion： The foreign gene, CD gene was correctly inserted into pGEX-1LambdaT plasmid and transferred into Bifidobacterium Infantis. Bifidobacterium Infantis/CD targeting gene therapy system was successfully constructed.     

靶向Bcl-2基因转录shRNA重组质粒的构建和序列分析

[目的]利用RNA干扰技术,以Bcl-2为靶基因,设计构建重组体,并进行序列分析,探索肿瘤基因治疗的新途径。[方法]设计有小发夹结构的两条DNA序列,经退火形成互补双链,克隆至转录载体Pgenesil-1上构建重组体,转化DH5a菌株,提取质粒行酶切鉴定后,进行测序分析。[结果]将合成的DNA片段退火后克隆至载体上,经酶切及序列鉴定为目的序列,靶向Bcl-2基因转录shRNA重组质粒构建成功。[结论]靶向Bcl-2基因转录shRNA重组质粒的成功构建,为下一步利用该重组体干扰肿瘤细胞中Bcl-2的mRNA转录,探索肿瘤基因治疗的新途径奠定基础。     

CEA siRNA载体的构建和转染人食管癌EC9706细胞的沉默作用

Objective: To construct the small interfering RNA (siRNA) expression vector of carcino-embryonic antigen (CEA) and inhibit the expression of CEA in EC9706 cells by RNA interference. Methods: Two pairs of oligonucleotide sequences were designed and synthesized according to the encoding sequence of mRNA of CEA. The annealed oligonucleotide frag-ments were cloned into pRNAT-U6.2 expression vector and identified by sequencing. The recombinant plasmid pRNAT-U6.2-CEA was transfected into EC9706 cells. The expression of CEA in the stable transfected cells was assayed by real time PCR and Western blot. Results: DNA sequencing showed that the oligonucleotide fragments were correctly inserted into pRNAT-U6.2 vector, and CEA expression in the transfected cells was down-regulated significantly by pRNAT-U6.2-CEA at both the mRNA and protein levels. Conclusion: The siRNA expression vector of CEA is successfully constructed and inhibits CEA expression in EC9706 cells. This facilitates further studies of the function of CEA at the molecular level.     

原核表达重组质粒pUC57－CTP－PTEN的构建及鉴定

目的：合成基因CTP及PTEN基因,构建其原核表达重组质粒pUC57－CTP－PTEN,为后续研究其功能做准备。方法：合成基因CTP－PTEN,将该基因定向克隆到原核表达载体pUC57中,构建pUC57－CTP－PTEN重组质粒,转化大肠杆菌DH5α菌株,抽提质粒进行双酶切、测序鉴定后,用Western blotting检验表达。结果：测序鉴定CTP－PTEN基因合成成功。经双酶切、测序鉴定证实重组质粒pUC57－CTP－PTEN 成功转入DH5α,Western blotting检验pUC57－CTP－PTEN成功表达。结论：成功构建了重组质粒pUC57－CTP－PTEN,并在大肠杆菌DH5α中成功表达。     

CYP3A5基因转染HL-60细胞介导耐药表型的研究

目的探讨CYP3A5基因与白血病细胞多药耐药的关系。方法克隆CYP3A5基因全长cDNA,构建CYP3A5基因真核表达重组质粒,稳定转染HL-60白血病细胞。采用四氮唑蓝法（MTT）测定化疗药的半数抑制量IC50值,采用流式细胞术（FCM）分析细胞周期及凋亡细胞百分比。结果空载质粒pcDNA3、重组质粒pcDNA3-CYP3A5稳定转染HL-60细胞。柔红霉素诱导后,HL-60和HL-60／pc细胞出现明显的凋亡峰,凋亡细胞比例分别为7．3％和6．3％;而HL-60／CYP3A5细胞则无明显凋亡峰,凋亡细胞比例为1．2％。HL-60／CYP3A5细胞与HL-60、HL60／pc细胞相比,显著耐受柔红霉素、阿克拉霉素、长春新碱和三尖杉酯碱,耐药倍数分别为2．89,2．01,4．05和2．79倍（P〈0．05）;而对鬼臼噻吩甙则无明显耐受,耐药倍数为1．04倍。结论CYP3A5基因的转录直接导致白血病细胞对蒽环类抗生素及生物碱类药物耐药,而对表鬼臼毒素仍然敏感。