前列腺源性ETS因子对HCT116细胞增殖与凋亡的影响

目的 探讨前列腺源性ETS因子(prostate-derived Ets factor,PDEF)对HCT116细胞增殖与凋亡的影响.方法 体外培养HCT116细胞,分成空白对照组,空质粒组和重组表达质粒组,空质粒组转染不含PDEF的空载体,重组表达质粒组转染PDEF重组表达质粒.荧光显微镜下观察PDEF重组质粒表达情况;RT-PCR、Western blot检测3组细胞PDEF mRNA和蛋白的表达情况;CCK8法检测细胞增殖情况;流式细胞仪检测细胞凋亡率.结果 荧光显微镜下空质粒组和重组表达质粒组HCT116细胞均可观察到绿色荧光蛋白的表达,表明质粒已成功转染HCT116细胞;RT-PCR结果显示,与空质粒组相比,重组质粒组PDEF基因表达增高263倍;Western blot结果可见重组质粒组有PDEF蛋白的表达,而空质粒组和对照组没有;CCK8法检测发现PDEF基因的表达能够明显抑制HCT116细胞的增殖(P＜0.05);流式细胞仪结果显示重组质粒组细胞凋亡率显著高于对照组和空质粒组(P＜0.05).结论 在HCT116细胞中表达前列腺上皮源性ETS转录因子,可以抑制细胞的增殖和促进细胞凋亡.     

125Ser－rIL－2工程菌稳定性研究

对产１２５Ｓｅｒ－ｒＩＬ－２工程菌稳定性进行了３个方面考察：１）工程菌传代后的重组质粒稳定性；２）工程菌传代后的重组质粒表达稳定性；３）传代工程菌中表达重组质粒的酶切图谱比较。结果表明，该工程菌传代２０～２００代的过程中，在本实验发酵条件下，其生物学活性保持在１０￣８ＩＵ／Ｌ范围。重组表达质粒无丢失现象，重组表达质粒的酶切图谱与原始酶切图谱比较是一致的。     

shRNA沉默STAT3基因对结肠癌细胞增殖及顺铂敏感性的影响

目的 构建携带信号转导与转录激活子3（STAT3）基因的短发夹RNA（shRNA）真核表达载体,观察pGPU6/GFP/Neo- STAT3重组质粒对HCT116细胞顺铂化疗敏感性的影响。方法 设计并构建稳定转录shRNA STAT3的质粒,采用脂质体法转染结肠癌HCT116细胞,Western blot法检测转染后STAT3蛋白表达变化,MTT法检测细胞增殖变化。重组质粒联合顺铂作用于HCT116细胞后,MTT法检测细胞存活率。结果 成功构建了pGPU6/GFP/Neo-STAT3重组质粒,测序证实重组质粒构建正确。重组质粒转染HCT116细胞后,细胞增殖明显受抑制,STAT3蛋白表达降低。重组质粒联合顺铂治疗后,细胞增殖活性显著降低。结论 shRNA STAT3重组质粒能明显降低HCT116细胞中STAT3蛋白的表达,抑制细胞增殖,提高结肠癌细胞对顺铂的敏感性。     

人甲状腺过氧化物酶膜外区基因的克隆及其杆状病毒表达载体的构建

摘要 目的：尝试克隆人甲状腺过氧化物酶（hTPO）膜外区基因并构建其杆状病毒表达载体,为其在昆虫细胞中的表达打好基础。方法：PCR扩增hTPO膜外区基因,并将其先后重组入pGEM3zf(+)质粒和pFastBac1质粒,以hTPO-pFastBAC1质粒转染E.coli DH10Bac大肠杆菌,获得重组hTPO杆状病毒表达载体（hTPO-Bacmid）,分别以多种方法鉴定其正确性。结果：经PCR及酶切、基因测序等方法证实得到的重组hTPO-pGEM3zf(+)质粒、hTPO-pFastBAC1质粒和hTPO-Bacmid均与预期相符。结论：成功的克隆了hTPO膜外区基因,并将其正确重组入pGEM3zf(+)质粒和pFastBac1质粒,后者经位点特异性转座整合至Bacmid,成功的构建了重组hTPO杆状病毒表达载体,为进一步实现hTPO在昆虫细胞中的真核表达作好了准备。     

Tudor-SN蛋白TSN结构域亚结构片段重组质粒的构建与表达

目的:研究人类Tudor-SN蛋白TSN结构域4个亚片段的功能,构建重组质粒pEGFP-C2-Tudor-SN-TSN(Ⅰ~Ⅳ)。方法:以重组质粒pSG5-Tudor-SN-flag为模板,聚合酶链反应(PCR)扩增出目的基因,将双酶切后带有粘性末端的目的片段和pEGFP-C2载体连接,从而构建重组质粒pEGFP-C2-Tudor-SN-TSN(Ⅰ~Ⅳ)。将构建成功的重组质粒用脂质体法转染HeLa细胞,并在荧光显微镜下观察融合蛋白的荧光表达情况,Western印迹检测融合蛋白的表达。结果:对重组质粒进行双酶切鉴定可见Tudor-SN-TSN(Ⅰ~Ⅳ)的cDNA片段;脂质体转染重组质粒后可观察到绿色荧光蛋白的表达。Western印迹后可在相应位置检测到融合蛋白pEGFP-C2-Tudor-SN-TSN(Ⅰ~Ⅳ)。结论:真核pEGFP-C2-Tudor-SN-TSN(Ⅰ~Ⅳ)重组质粒构建及表达成功。     

PML-RARα融合基因相关蛋白原核表达载体的构建、表达和纯化

目的 构建PML-RAR o[融合基因相关重组表达质粒,在大肠埃希菌中表达可溶性蛋白并进行纯化.方法 利用聚合酶链反应(Polymerase Chain Reaction,PCR)以PML-RAR α全长质粒为模板分别扩增出长度均为1 200 bp的PML和RAR o[序列,并将它们分别插入PET32a(+)质粒中,构建重组表达质粒,化学法转化大肠埃希菌DH5α进行克隆,菌落PCR筛选阳性转化子,双酶切和测序鉴定重组质粒的正确性.正确重组的表达质粒分别命名为PML-Flag-PET32a(+)和Flag-RARα-PET32a(+).将正确重组的表达质粒转化感受态大肠埃希菌BL21(DE3),经异丙基β-D-半乳糖苷(IPTG)诱导表达,利用表达蛋白的组氨酸“标签”(His-tag)进行Ni2+-树脂柱亲和层析纯化,SDS-PAGE和Western blotting鉴定纯化蛋白质.结果 PCR扩增获得目的基因,重组表达质粒经EcoRI/HindⅢ双酶切和测序鉴定证明构建正确.转化感受态BL21(DE3)并经诱导后得到高效表达,SDS-PAGE和Western blotting显示纯化蛋白为目的蛋白.结论 成功构建重组表达质粒,并经诱导表达后可纯化出目的蛋白,为进一步的抗体制备等实验奠定了基础.     

HCV Core基因真核表达载体构建及其对HeLa细胞自噬的影响

目的 构建丙型肝炎病毒（HCV）核心蛋白（Core）真核表达载体,并研究其对人宫颈癌 HeLa细胞自噬功能的影响。方法 以 HCV复制子质粒 pJFH1为模板,PCR法扩增 HCV Core 基因片段,经纯化回收后与 PLVX-IRESZsGreen1载体用同源重组法相连,构建 PLVX-IRES-ZsGreen1-Core重组质粒,并经测序验证其序列的正确性。转染宫颈癌 HeLa细胞,并设 PLVX-IRES-ZsGreen1-Core重组质粒转染组、PLVX-IRES-ZsGreen1空载体转染对照组以及未转染质粒空白对照组,通过免疫印迹法验证 HCV Core蛋白在 HeLa细胞中的表达,并用免疫荧光（IF）和免疫印迹检测自噬生物标记物微管相关蛋白 1轻链 3（LC3）的表达水平。结果 获得 PLVX-IRES-ZsGreen1-Core重组质粒,测序结果表明构建的重组质粒序列完全正确,HCV Core重组蛋白可在 HeLa细胞中有效表达;免疫荧光和免疫印迹结果表明,HCV Core过表达细胞 LC3焦点和 LC3 Ⅱ蛋白表达水平明显增多,PLVX-IRES-ZsGreen1-Core重组质粒转染组的细胞 LC3 Ⅱ水平（1.069±0.049）高于 PLVX-IRES-ZsGreen1空载体转染对照组（0.776±0.047）,差异有统计学意义（P＜0.05）。结论 成功构建了 PLVX-IRES-ZsGreen1-Core 重组质粒,HCV Core 蛋白过表达可诱导 HeLa 细胞自噬。     

SLPI基因真核表达质粒的构建和鉴定

目的构建并鉴定含分泌型白细胞蛋白酶抑制蛋白(SLPI)基因的重组真核表达质粒。方法以HeLa细胞的总RNA为模板,用RT-PCR方法扩增出SLPI基因cDNA,将产物克隆进真核载体pcDNA3.1(+)内,构建含SLPI基因的重组真核表达质粒。将pcDNA-SLPI重组质粒和空载体pcDNA分别转染HeLa细胞,Western blot检测SLPI蛋白表达。结果核酸序列分析及双酶切鉴定SLPI已成功插入pcDNA3.1(+)载体中,转染pcDNA-SLPI的HeLa细胞中检测到高表达的SLPI蛋白。结论成功构建了含SLPI基因的重组真核表达质粒。     

大鼠谷氨酰胺转运蛋白SNAT1-EGFP融合蛋白的构建与鉴定

目的利用分子生物学方法构建大鼠谷氨酰胺转运蛋白1重组质粒p EGFP-N1-SNAT1并进行鉴定。方法对载体p EGFP-N1和质粒p BK-CMV(Δ[1098-1300])-SNAT1双酶切,纯化后连接,构建重组质粒p EGFP-N1-SNAT1。用Western blot检测融合蛋白的表达,采用免疫荧光检测SNAT1在细胞膜上的表达和定位。结果成功构建重组质粒p EGFP-N1-SNAT1并正常表达、定位于细胞膜上。结论重组质粒p EGFP-N1-SNAT1的成功构建为研究SNAT1的结构和功能提供了有效工具。     

野生型DPP Ⅳ真核表达质粒的构建和鉴定

目的构建野生型DPP Ⅳ真核表达质粒。方法将野生型DPP Ⅳ基因定向克隆到真核表达质粒pcDNA3.1(+),构建成重组质粒pcDNA3 DPP Ⅳ;然后用限制性内切酶消化和DNA序列测定鉴定。结果经酶切和DNA序列测定鉴定证实重组质粒构建正确。结论真核表达质粒pcDNA3DPP Ⅳ构建成功,为进一步研究DPP Ⅳ基因在卵巢癌细胞中的表达和生物学作用奠定了基础。     

A comparison of neurotrophic effects of epidermal growth factor and basic fibroblast growth factor in primary cultured neurons from various regions of fetal rat brain

Effects of recombinant human epidermal growth factor (hEGF) on survival of primary cultured neurons from various regions of fetal rat brain were compared with those of recombinant human basic fibroblast growth factor (hbFGF). Addition of hEGF (0.001-10 ng/ml) in chemically-defined serum-free medium enhanced significantly the survival of cultured neurons from all regions tested, i.e., cerebral cortex, septum, striatum, hippocampus, thalamus, colliculus and cerebellum. However, its effective concentration differed considerably with the regions. The most sensitive regions were the colliculus and cerebellum (minimum effective concentration, 0.001 ng/ml), while the least sensitive was the cerebral cortex (minimum effective concentration, 10 ng/ml). Maximum numbers of surviving neurons in the presence of hEGF were smaller than those of hbFGF in all regions. Maximum effects of hEGF compared with those of hbFGF was greatest in the striatum and smallest in the cerebral cortex. These results suggest that hEGF may exert neurotrophic effects for limited populations of brain neurons. When hEGF (1-10 ng/ml) and hbFGF (0.01-10 ng/ml) were added together, hEGF increased the effects of a lower concentration of hbFGF in an additive manner, but the maximum effects of hbFGF were not potentiated by hEGF in all regions tested. Therefore, mechanisms underlying the effects of hEGF very probably overlap with those of hbFGF.     

Effects of recombinant human basic fibroblast growth factor and its modified protein CS23 on survival of primary cultured neurons from various regions of fetal rat brain

Neutrophic effects of recombinant human basic fibroblast growth factor (hbFGF) and its modified protein CS23 on brain neurons were evaluated by their abilities to promote survival of primary cultured neurons from various regions of fetal rat brain. In the molecule of CS23, two serines are substituted for two cysteines at positions 70 and 88 in the natural hbFGF. Both hbFGF and CS23 markedly increased the survival of cultured neurons from all regions tested, i.e., cerebral cortex, septum, striatum, hippocampus, thalamus, substantia nigra, colliculus and cerebellum. The effects were concentration-dependent, in the range of 0.01 to 10 ng/ml, in similar manners among all regions. Although the maximal number of surviving neurons in the presence of CS23 was little different from that of hbFGF, CS23 could significantly promote neuronal survival at a lower concentration than hbFGF. The time-course of these effects on survival was almost the same between hbFGF (1 ng/ml) and CS23 (1 ng/ml). These results suggest that hbFGF has a strong neurotrophic activity on a wide range of brain neurons and that CS23 maintains the activity of original hbFGF successfully.     

Noninvasive transdermal iontophoretic delivery of biologically active human basic fibroblast growth factor

Human basic fibroblast growth factor (hbFGF; 17.4 kDa) has shown promise in the treatment of several dermatological conditions; symptomatic improvement was also observed in patients with peripheral arterial disease after arterial infusion. The objective of this study was to demonstrate the feasibility of using transdermal iontophoresis to deliver biologically active hbFGF noninvasively into and across the skin. The protein was cloned, expressed and purified in-house. Porcine skin was used to investigate transdermal iontophoretic transport of hbFGF as a function of current density (0.15, 0.3, and 0.5 mA/cm(2)); results were subsequently confirmed using human skin. Cumulative hbFGF permeation and skin deposition were quantified by ELISA. The absence of proteolytic degradation during skin transit was confirmed by SDS-PAGE. Biological activity postdelivery was determined using cell proliferation assays in human foreskin fibroblast (HFF) and NIH 3T3 cell lines. Confocal laser scanning microscopy (CLSM) was used to visualize the distribution of rhodamine-tagged hbFGF in the skin. Cumulative iontophoretic permeation at 0.3 mA/cm(2) was statistically superior to that at 0.15 mA/cm(2); however, there was no further improvement at 0.5 mA/cm(2). Significant skin deposition of hbFGF was observed, and this dominated transport; for example, after iontophoresis for 8 h at 0.5 mA/cm(2), skin deposition (77.74 ± 37.36 μg/cm(2)) was 4.4-fold higher than cumulative permeation (17.64 ± 5.18 μg/cm(2)). The superior skin deposition may be advantageous for dermatological applications. The HFF and NIH 3T3 cell proliferation assays confirmed that biological activity of hbFGF was retained postdelivery. Coiontophoresis of acetaminophen showed that the dominant transport mechanism switched from electroosmosis to electromigration upon increasing current density from 0.15 to 0.3 mA/cm(2). Experiments using human skin confirmed that iontophoretic permeation of hbFGF across porcine and human membranes was statistically equivalent. CLSM images of rhodamine-tagged hbFGF postiontophoresis indicated that the protein was evenly distributed throughout the epidermis and dermis. In conclusion, the results confirmed that transdermal iontophoresis was indeed able to deliver structurally intact, functional hbFGF noninvasively into and across the skin. The amounts of protein delivered were similar to those in reports from preclinical and clinical studies.     

非融合重组人碱性成纤维细胞生长因子在大肠杆菌中的克隆及高效表达

目的:获得大肠杆菌中高效表达的非融合重组人碱性成纤维细胞生长因子(rhbFGF).方法:采用RT-PCR技术,以人胎儿脑组织的总RNA克隆出hbFGF基因,再以此为模板,设计引物,对hbFGF的TIR(翻译起始区)部分碱基进行改造和降低G C含量,最后将该新基因克隆于质粒载体pET-3C,转化于大肠杆菌中表达.结果:非融合rhbFGF在大肠杆菌中高效表达,占总蛋白量的30％以上.采用离子交换和亲和层析方法纯化后,生物活性与标准蛋白一致.结论:非融合rhbFGF及调整TIR区域的碱基序列能有效提高重组蛋白的表达效率.     

靶向mdr1基因转录小发夹RNA重组质粒的构建和序列分析

目的 构建针对多药耐药基因(mdr1)编码区的发夹状RNA重组质粒栽体pshRNA-mdr1,并行序列分析,为下一步逆转肿瘤的多药耐药性打下基础。方法设计含19-21bp mdrl编码基因片段及中间以4个bp间隔的反向重复序列,经退火形成互补双链,克隆至转录栽体pTZU6 1上,转化JM109菌株,提取重组质粒酶切鉴定并序列分析。结果将合成的DNA片段成功克隆至载体上,经酶切及序列鉴定为目的序列。结论靶向mdr1基因发夹状RNA干扰重组质粒的成功构建,可进一步研究其对mdr1 mRNA转录的抑制,达到逆转肿瘤的多药耐药性的目的。     

利用Gateway技术构建重组腺病毒pAd-NK4

目的利用Gateway技术构建含人肝细胞生长因子(HGF)NK4基因的重组腺病毒载体。方法以含有HGF/NK4基因的质粒为模板PCR扩增NK4基因,将回收的NK4PCR产物片段克隆至腺病毒穿梭载体pYr-adshuttle-6获得重组质粒pYr-adshuttle-6-NK4。从该重组质粒上,利用LR同源重组将NK4-IRES-EGPF表达框转移至腺病毒骨架质粒pAD/BL-DEST,获得重组腺病毒质粒pAd-NK4-IRES-EGFP。该质粒经pacI线性化后转染293包装细胞,获得重组腺病毒rAd-NK4-IRES-EGFP。采用TCID 50(tissue cell infectiousdosage 50,TCID 50)法测定重组腺病毒滴度。重组腺病毒分别经酶切和PCR等方法进行鉴定。荧光显微镜观察转染效果。结果证实腺病毒载体中含有NK4基因的目的片段;病毒滴度为6.3×1011 PFU.L-1;荧光显微镜发现该重组腺病毒能在HEK293细胞中高效的表达。结论利用Gateway技术可以快速地构建同时表达NK4蛋白和绿色荧光的重组腺病毒,为下一步开展关于NK4基因的肿瘤治疗提供了基础。     

构建干扰RhoA的短发夹RNA真核表达载体

目的利用pGenesil-1质粒构建针对RhoA的短发夹RNA(shRNA)表达载体。方法设计2个shRNA结构的互补DNA序列,经退火成双链,胶回收酶切pGenesil-1大片段,T4DNALigase连接酶切大片段和DNA序列,得到质粒pGenesil-1-RhoA1和pGenesil-1-RhoA2.转化感受态细胞DH5a,扩增,提取重组质粒进行酶切鉴定。结果成功构建靶向RhoA的shRNA重组质粒载体.酶切鉴定和测序分析重组质粒,shRNA编码序列与设计的片段完全一致,经酶切凝胶电泳证实载体构建成功。结论表达靶向RhoA的shRNA表达框成功构建在重组质粒载体上。     

人血管内皮抑素腺相关病毒载体包装质粒0pSNAV-hEndostatin-CMV-EGFP的构建

目的:构建人血管内皮抑素(Endostatin)腺相关病毒(Adeno-associated virus,AAV)载体包装质粒pSNAV-hEndostatin-CMV-EGFP.方法:采用分子克隆技术,从pCD-sEndostatin质粒获得hEndostatin cDNA,并将PCR扩增产物插入至AAV包装质粒pSNAV上,构建pSNAV-hEndostatin-CMV-EGFP的AAV重组质粒,经PCR、酶切及测序鉴定.结果:经PCR、酶切鉴定及基因测序证实AAV包装质粒pSNAV-hEndostatin-CMV-EGFP构建成功.结论:构建的AAV包装质粒pSNAV-hEndostatin-CMV-EGFP可作为rAAV-hEndostatin-EGFP表达载体的包装质粒.     

RNA interference by expression of short hairpin RNAs suppresses bcl-xL gene expression in nasopharyngeal carcinoma cells

Aim: To evaluate a new plasmid mediated RNA interference (RNAi) system and investigate whether knock-down of bcl-xL by short hairpin RNA (shRNA) can induce apoptosis of human nasopharyngeal carcinoma (NPC) cell line CNE-2Z in vitro. Methods: The plasmid containing mU6 promoter was subcloned to yield the pmU6 plasmid, recombinant plasmid expressing shRNA targeting bcl-xL gene was designed and constructed, and were co-transfected cells with green fluorescence protein expressing plasmid. Flow cytometry was used to evaluate transfection efficiency, and RT-PCR and Western blot were applied to analyze bcl-xL mRNA and protein levels, respectively. Results: The shRNA expressed by the recombinant plasmid efficiently suppressed bcl-xL gene expression and induced apoptosis of NPC cells in vitro. Conclusion: The recombinant plasmid can sufficiently mediate RNAi in CNE-2Z cells, and knock-down of the bcl-xL expression by shRNA significantly induced apoptosis in CNE-2Z cells. The results suggest this new system, mediated RNAi can be used as a tool for the study of gene function and gene therapy.