Construction of a recombinant eukaryotic expression plasmid containing human PDLIM2 gene and its biological activity

In order to obtain a full-length expression plasmid for human PDLIM2 gene, fragment amplification was used to clone its full-length coding sequence (CDS) region. The amplified PCR product was then digested and inserted into the pMD 18-T vector and subcloned into the pIRES2-EGFP plasmid to form the pIRES2-EGFP-PDLIM2 eukaryotic expression vector. After it was transfected to the bladder cancer cell line, BIU-87, the biological activities of high expression were verified by RT-PCR and Western blotting. Meanwhile the mRNA and protein expressions of p65 were detected. Finally we analyzed the effect of overexpressed PDLIM2 on BIU-87 cell proliferation. In conclusion, a recombinant eukaryotic expression vector pIRES2-EGFP-PDLIM2 containing the complete CDS region of PDLIM2 was successfully constructed. PDLIM2 negatively regulated p65 expression and inhibited BIU-87 cell proliferation. We laid the foundations for further research into the function of the PDLIM2 gene in bladder cancer.     

真核表达质粒pcDNA3.1-CSRP2-HA的构建及鉴定

目的:构建并鉴定真核表达质粒PcDNA3.1-CSRP2-HA。方法:据GeneBank中人CSRP2 CDS序列设计并合成引物,提取A549细胞总RNA,并将其逆转录成cDNA作为模板,进行PCR扩增,获得CSRP2目的基因后,再与PcDNA3.1-HA载体进行连接重组,构建PcDNA3.1-CSRP2-HA真核表达质粒,经限制性内切酶消化、PCR及DNA序列测序分析等方法鉴定后,瞬时转染入A549细胞,Western blot法检验CRP2蛋白表达。结果:成功构建PcDNA3.1-CSRP2-HA真核表达质粒,Western-blot结果显示PcDNA3.1-CSRP2-HA能够在A549细胞中表达。结论:PcDNA3.1-CSRP2-HA真核表达质粒构建并鉴定成功,为后续研究CRP2在炎症诱发氧化损伤机制中的转录调控作用奠定了基础。     

小鼠EVL 基因的克隆和真核表达载体的构建

目的:构建小鼠EVL(Ena/VASP like)基因的真核表达载体,为深入研究EVL的功能奠定基础.方法:采用PCR方法,从小鼠cDNA文库中,扩增出1245bp的EVL编码区片段,经电泳、胶回收后连接入pMD- 18T载体中,测序鉴定正确.用BamHI和HincⅡ双酶切,定向克隆EVL编码区片段到真核表达载体pcDNA3.1中,用限制性内切酶酶切鉴定重组质粒正确后.将重组质粒转染入HELA细胞中,以RT-PCR检测EVL的mRNA的表达,以Western Blot检测EVL蛋白的表达.结果:酶切鉴定结果显示小鼠EVL编码区基因被成功克隆入真核表达载体pcDNA3.1中;RT-PCR和Western Blot结果以及免疫荧光染色显示Hela细胞中有EVL的mRNA和蛋白的表达.结论:成功获得pcDNA3.1 -EVL的真核表达载体,为进一步深入研究EVL蛋白的功能奠定了基础.     

Construction, characterization and expression of full length cDNA clone of sheep YAP1 gene

RT-PCR, 5′RACE, 3′RACE were used to clone sheep full length cDNA sequence of YAP1 (Yes-associated protein 1), eukaryotic expression plasmid and a mutant that cannot be phosphorylated at Ser42 was successfully constructed. The amino acid sequence analysis revealed that sheep YAP1 gene encoded water-soluble protein and its relative molecular weight and isoelectric point was 44,079.0 Da and 4.91, respectively. Sub-cellular localization of YAP1 was in the nucleus, it is hydrophilic non-transmembrane and non-secreted protein. YAP1 protein contained 33 phosphorylation sites, seven glycosylation sites and two WW domains. The secondary structure of YAP1 was mainly composed of random coil, while the tertiary structure of domain area showed a forniciform helix structure. YAP1 gene was expressed in different tissues, the highest expression was in kidney and the lowest was in hypothalamus. The CDS of sheep YAP1was amplified by RT-PCR from healthy sheep longissimus dorsi muscle, cloned into pMD19-T simple vector by T/A ligation. YAP1 coding region was further sub-cloned into pEGFP-C1 vector by T4 Ligase to construct a eukaryotic expression plasmid and then make the eukaryotic expression vector as the template to construct the phosphorylation site mutant. PCR, restriction enzyme and sequencing were used to confirm the recombinant plasmid. The sheep full-length YAP1 cDNA sequence is 1712 in length encoding 403 amino acids. It was confirmed that the sheep YAP1 CDS was correctly inserted into eukaryotic expression vector and serine had been mutated to alanine by PCR, restriction digestion and sequencing. The result showed that the recombinant plasmid pEGFP-C1-YAP1 and pEGFP-C1-YAP1 S42A was constructed correctly, this will help for further studies on the YAP1 protein expression and its biological activities.     

胰岛素样生长因子结合蛋白-7基因的克隆和表达

IGFBP-7是胰岛素样生长因子结合蛋白(IGFBP)家族中的一员,具有一些抑癌基因的特征。利用重组PCR技术获得了IGFBP-7基因的全长编码区序列,并将其克隆到pcDNA3．1／His—Myc真核表达载体中,得到重组质粒pcDNA3．1／His—Myc—IGFBP-7。将该重组质粒瞬时转染人胚胎肾293T细胞,Westem-blot分析表明,IGFBP-7在293T细胞中获得了表达,为进一步研究IGFBP-7的功能奠定了基础。     

转录因子AP-4基因真核表达载体构建及表达分析

本研究利用生物信息学分析AP-4与胃癌患者临床病理信息的相关性,根据GenBank中人AP-4基因cDNA序列设计并合成特异性引物,以胃癌细胞总RNA逆转录的cDNA为模板,利用高保真酶扩增AP-4基因CDS (Coding DNA sequence)序列并构建入pcDNA3.1+载体,并通过限制性内切酶酶切分析和测序法进行进一步验证;脂质体法将AP-4重组表达载体及对照pcDNA3.1+载体转染胃癌细胞,qRT-PCR(Quantitative real time polymerase chain reaction)和Western blotting检测分别检测AP-4在m RNA和蛋白水平的表达。生物信息学分析发现,AP-4的表达与胃癌分期及预后显著相关;酶切及测序分析表明,转录因子AP-4真核表达载体构建成功,并能够在胃癌细胞中实现转录和蛋白水平的高效表达。此研究为深入研究转录因子AP-4在胃癌等肿瘤发生发展中的作用及分子机制奠定了基础。     

小鼠可溶性PD1的克隆、真核表达及生物学活性检测

旨在克隆小鼠PD1胞外区(简称mPD-1)基因,利用真核表达系统表达有活性的分泌型mPD-1蛋白,初步研究其生物学活性。克隆mPD-1基因,将其连入pcDNA3.1(+)/Fc中获得pcDNA3.1(+)-Fc/mPD-1重组表达质粒,转化至大肠杆菌DH5α,进行PCR和双酶切鉴定,并送测序。将阳性质粒转染L929细胞,利用RT-PCR和Western blotting方法鉴定mPD-1/L929稳定表达株。利用Alamar Blue法检测分泌的mPD-l蛋白对淋巴细胞增殖的影响,评价其生物学活性。结果显示,成功构建重组质粒pcDNA3.1(+)-Fc/mPD-1,转染了pcDNA3.1(+)-Fc/mPD-1的L929细胞可将mPD-l蛋白分泌至胞外。A lamar Blue检测结果显示,真核细胞分泌的mPD-1蛋白作用于混合淋巴细胞,与阴性对照相比,可明显促进淋巴细胞的增殖。本试验成功地克隆mPD-1胞外区蛋白,并在L929细胞中得到了分泌型表达。分泌的重组蛋白可有效促进淋巴细胞增殖,为进一步研究其功能和临床应用提供了条件。     

grp78真核表达载体构建及其稳定转染HeLa细胞系建立

目的构建人grp78基因真核表达载体,并建立稳定高表达grp78的人宫颈癌HeLa细胞系。方法用RT—PCR方法从人宫颈癌HeLa细胞中扩增grp78基因编码区,将PCR产物克隆到pcDNA3．1（＋）真核表达载体,构建重组质粒pcDNA3．1（＋）／grp78并测序鉴定。用构建成功的pcDNA3．1（＋）／grp78真核表达载体转染入人宫颈癌HeLa细胞,经G418筛选获得grp78稳定高表达的HeLa细胞系,并用RT—PCR及Western印迹方法鉴定。结果成功构建pcDNA3．1（＋）／grp78真核表达载体,筛选获得稳定高表达人grp78的HeLa细胞系。结论grp78真核表达载体的成功构建和稳定高表达grpTS的HeLa细胞系的建立为进一步研究grp78的功能奠定了基础。     

协同激活分子CBP诱饵表达质粒的构建和鉴定

构建协同激活分子CBP（CREB（cAMP response element binding）binding protein）的诱饵表达质粒pGBKT7-CBP并检测其蛋白表达、毒性和自激活作用.PCR扩增小鼠CBP的基因编码序列（CDS（coding sequence）序列）并克隆入诱饵表达载体pGBKT7中,通过酶切和测序鉴定后,把构建好的诱饵表达质粒pGBKT7-CBP转化到酵母AH109细胞中,Western blot检测诱饵蛋白表达情况,同时检测诱饵蛋白的毒性和自激活作用.结果成功扩增了小鼠CBP基因的CDS序列,并成功克隆到酵母诱饵表达载体pGBKT7中,测序结果正确.诱饵表达质粒成功转化到酵母AH109细胞中,Western blot分析结果证实酵母细胞高表达诱饵蛋白CBP,但诱饵蛋白有自激活作用.提示pGBKT7-CBP不能用于酵母双杂交或三杂交系统检测CBP与其他蛋白质或小分子的相互作用,对其他研究CBP生物学功能试验的方法选取具有一定的借鉴意义.     

iASPP/p63 autoregulatory feedback loop is required for the homeostasis of stratified epithelia

iASPP, an inhibitory member of the ASPP (apoptosis stimulating protein of p53) family, is an evolutionarily conserved inhibitor of p53 which is frequently upregulated in human cancers. However, little is known about the role of iASPP under physiological conditions. Here, we report that iASPP is a critical regulator of epithelial development. We demonstrate a novel autoregulatory feedback loop which controls crucial physiological activities by linking iASPP to p63, via two previously unreported microRNAs, miR-574-3p and miR-720. By investigating its function in stratified epithelia, we show that iASPP participates in the p63-mediated epithelial integrity program by regulating the expression of genes essential for cell adhesion. Silencing of iASPP in keratinocytes by RNA interference promotes and accelerates a differentiation pathway, which also affects and slowdown cellular proliferation. Taken together, these data reveal iASPP as a key regulator of epithelial homeostasis.     

牛c-myc基因的克隆及其在皮肤成纤维细胞中的表达

为了构建包含牛c-myc基因编码序列的重组载体,以胎牛原始生殖嵴为材料,用RT-PCR方法克隆出牛c-myc 基因的编码序列,将其亚克隆至pMD19-T载体,再从酶切鉴定和测序正确的质粒上切下目的片段,定向克隆到pIRES2-AcGFP1-Nuc表达载体上,挑选序列正确的重组真核表达质粒转染牛皮肤成纤维细胞,用RT-PCR和Western blotting分别检测c-myc mRNA和蛋白的表达。结果表明,从胎牛原始生殖嵴中正确克隆了c-myc基因的全长编码序列,所构建的重组质粒能够在皮肤成纤维细胞中有效     

小鼠Uncv基因克隆及真核表达

目的 克隆小鼠的Uncv基因并在真核细胞表达.方法 采用RT-PCR方法扩增小鼠皮肤组织中Uncv基因编码区,以真核表达质粒pcDNA 3.1-Flag为载体,构建Uncv真核表达质粒,将重组载体转染Hela细胞并用Western blot法检测基因表达.结果 构建Uncv基因真核表达载体pcDNA 3.1-Flag/Unev,重组质粒在Hela细胞中有效表达约95×103的融合蛋白.结论 成功构建真核表达载体pcDNA 3.1-Flag/Uncv,并且在真核细胞中有效表达,为研究Uncv基因生物学功能奠定基础.     

RNA interference-mediated silencing of iASPP induces cell proliferation inhibition and G0/G1 cell cycle arrest in U251 human glioblastoma cells

iASPP is an evolutionally conserved inhibitory member of the ASPP (apoptosis-stimulating protein of p53) protein family. Overexpression of iASPP was observed in several types of human tumors, however, its role in tumorigenesis has not been fully clarified. To investigate the role of iASPP in human glioblastoma multiforme (GMB) progression, the authors employed lentivirus-mediated shRNA to silence endogenous iASPP expression and elucidated iASPP function by analysis of viability, colony formation, DNA synthesis, and cell cycle in p53-mutant glioblastoma cell line U251. iASPP was significantly and sustainably knocked down by iASPP-specific shRNA in U251 cells. Stable down-regulation of iASPP expression-induced cell proliferation inhibition and G0/G1 cell cycle arrest by down-regulation of cyclin D1 and up-regulation of p21(Waf1/Cip1). Thus, the findings not only provide a molecular basis for the role of iASPP in cell cycle progression of glioblastoma cells but also suggest a novel therapeutic target for the treatment of GBM.     

Isolated DNA repeat region from fcrA76, the Fc-binding protein gene from an M-type 76 strain of group A streptococci, encodes a protein with Fc-binding activity

The DNA repeat region of fcrA76, the gene encoding a group A streptococcal Fc-binding protein, was subcloned in-frame into an Escherichia coli plasmid expression vector. The expressed protein product displayed the same Fc-binding properties as the full-length Fc-binding protein expressed from fcrA76. The affinity-purified, full-length Fc-binding protein was found to compete with staphylococcal protein A or streptococcal protein G for binding to beads coated with human IgG. These results are consistent with earlier studies suggesting that the binding sites on human IgG for protein A, protein G and the type II Fc-binding protein from group A streptococci are located at the interface of the CH2 and CH3 domains of the Fc region.     

Characterization and in vitro expression of non-structural 1 protein of canine parvovirus (CPV-2) in mammalian cell line

Parvoviruses are small, 260-A-diameter, icosahedral, non-enveloped, single-stranded DNA viruses with a genome of approximately 5 kb. Non structural protein, (NS-1) is especially relevant, being both essential for virus replication and the main factor responsible for virus pathogenicity and cytotoxicity. This protein has also been reported to possess the property of killing of transformed cells. The present study was carried out to clone, characterize and express the NS-1 gene of canine parvovirus. NS-1 complete CDS 2020bp was amplified, cloned into eukaryotic expression vector pcDNA 3.1(+), sequenced and characterized by in vitro expression analysis. Functional activity of recombinant construct, pcDNA.cpv.NS-1, was evaluated by RT-PCR and flow cytometry for the expression of NS-1 specific mRNA and NS-1 protein, respectively, in transfected HeLa cells. This recombinant plasmid may serve as an important tool to evaluate the apoptotic potential of NS-1 protein of canine parvovirus in cultured HeLa cells.     

大鼠大麻素Ⅰ型受体绿色荧光融合蛋白真核表达载体的构建与鉴定

目的:构建大鼠大麻素型Ⅰ受体绿色荧光融合蛋白真核表达载体并观察其在细胞中的表达。方法:大鼠CB1基因序列设计引物,以大鼠脑组织为模板扩增CB1基因编码区片段,克隆至增强型绿色荧光蛋白表达载体pEGFP-N3中,构建重组融合蛋白表达载体pCB1-EGFP。将pCB1-EGFP质粒转染HeLa细胞,通过观察EGFP报告基因的表达以及免疫荧光,Western Blot方法鉴定CB1可在真核细胞中过表达情况。结果:构建重组融合蛋白表达载体pCB1-EGFP,单双酶切和测序验证正确。将pCB1-EGFP质粒转染HeLa细胞,荧光显微镜下观察到融合表达的绿色荧光蛋白,且呈胞膜表达。免疫荧光试验也证明重组载体转染后,CB1基因和GFP共同定位于胞膜部分。Western Blot实验证明表达CB1蛋白。结论:成功构建了高表达的CB1-EGFP融合蛋白真核表达载体。     

小鼠DLL1真核表达载体的构建及其在肿瘤细胞中的表达

目的：构建带绿色荧光蛋白的小鼠DLL1全长基因真核表达载体,并在肿瘤细胞中表达。方法：利用PCR特异性引物扩增出DLL1基因全长,将克隆的基因片段插入带绿色荧光蛋白的真核表达载体pIRES2-EGFP质粒中。然后利用脂质体将重组质粒pIRES2-EGFP-DLL1转染进小鼠B16黑色素瘤细胞中,并通过G418筛选后选取生长良好、荧光强度高的三株单克隆进行mRNA水平DLL1表达的鉴定。结果：成功扩增小鼠DLL1的全长基因。克隆入质粒载体后,通过DNA序列测定证实其序列正确。将构建的pIRES2-EGFP-DLL1质粒转染小鼠B16黑色素瘤细胞,经过G418筛选和荧光显微镜观察后,挑选得到GFP阳性率90%以上的稳定转染细胞株。RT-PCR检测稳定转染细胞的mDLL1的表达显著增加,进一步证实了pIRES2-EGFP-DLL1的表达效能。结论：成功构建了小鼠DLL1基因的真核表达质粒,证实其在真核细胞B16中可以表达。