Salusin-a基因真核表达载体的构建及在HEK293细胞中的表达

目的:研究增强型绿色荧光蛋白真核表达载体Salusin-a(pEG-FP-Salusin-a)的构建及在人胚胎肾细胞系293细胞(HEK293)中的表达。方法:提取人单核细胞系THP-1细胞Salusin-a的mRNA,逆转录多聚酶链反应(RT-PCR)扩增Salusin-a基因,克隆入pEGFP-N3载体,双酶切、菌落PCR及测序鉴定pEGFP-Salusin-a质粒。用脂质体转染pEGFP-Salusin-a入HEK293细胞,分为转染细胞组、质粒对照组和空白对照组,检测分析各组荧光蛋白和Salusin-a基因的表达。结果:成功构建pEGFP-Salusin-a质粒,并转染HEK293,细胞转染效率86%,转染细胞组和质粒对照组绿色荧光蛋白的表达明显高于空白对照组(P0.05);转染细胞组Salusin-amRNA的表达明显高于质粒对照组和空白对照组(P0.05)。结论:重组pEGFP-Salusin-a质粒能转染HEK293细胞并表达Salusin-a,为Salusin-a基因功能的进一步研究提供了实验基础。     

pRluc-hKOR-pcDNA3.1 真核重组质粒的构建及在HEK293细胞中的表达

目的： 构建与海肾荧光素酶(renilla luciferase,Rluc)融合的人κ型阿片受体（kappa opioid receptor, KOR）的真核表达载体,用于生物发光共振能量转移法检测人KOR与其它受体间的相互作用。方法: 以质粒pcDNA3.1-hKOR为模板,PCR方法扩增人KOR。扩增的人KOR用NotⅠ和XhoⅠ双酶切,同时用这2种酶双酶切质粒pRluc-pcDNA3.1。然后将这2种酶切产物按常规方法连接、转化大肠杆菌Top10。挑取菌落培养,提取质粒,然后进行酶切鉴定,最后进行测序。将测序正确的重组载体用脂质体法转染人胚胎肾（human embryonic kidney 293,HEK293) 细胞,免疫荧光染色,共聚焦显微镜观察。结果: 扩增出了1条约1.2 kb的片段,与预期的人KOR大小相符,质粒酶切结果显示重组质粒 pRluc-hKOR-pcDNA3.1被切成2条片段,其中1条为pRluc-pcDNA3.1载体大小,另1条为目的片段大小。经测序鉴定,序列与GenBank (NM_000912)中的序列高度同源。共聚焦显微镜观察显示,阿片受体主要表达在细胞膜上。结论: 构建成功了pRluc-hKOR-pcDNA3.1重组真核表达载体,此表达载体可用于检测人KOR与其它受体之间的相互作用。     

人CD23基因的扩增及其在HEK 293T细胞的高效表达

目的建立一个有效表达CD23的系统。方法采用RT-PCR方法,从外周血淋巴细胞中扩增人的CD23cDNA基因,并将其克隆到真核表达载体pcDNA3·1B上,构建成pcDNA3·1/CD23质粒表达载体;将pcDNA3·1/CD23质粒转染HEK293T细胞,通过流式细胞仪和Westernblot检测CD23在细胞中的表达情况。结果扩增的CD23cDNA序列与文献报道的一致;通过构建表达载体和转染细胞实现了CD23cDNA在293T细胞膜上的表达。转染效率达80%以上,并获得了较高水平的表达。结论扩增CD23cDNA基因,经过转染HEK293T细胞,实现了CD23在HEK293T细胞的高效表达。     

人趋化因子受体CCR6在HEK293细胞内的稳定表达及其功能分析

目的:构建稳定表达人趋化因子受体6(CCR6)的HEK293细胞株。方法:将CCR6基因和Gα16质粒共转到HEK293细胞中,并挑取稳定表达CCR6基因的HEK293细胞克隆。采用体外趋化实验、钙流实验、RT-PCR、Western blot及免疫荧光染色法,检测CCR6在HEK293细胞表面的表达。结果:经上述实验证实,CCR6基因和Gα16质粒共转染的HEK293细胞上,可稳定表达CCR6,且具有生物学活性。结论:成功地在HEK293细胞表面稳定表达具有生物学活性的CCR6,为研究CCR6的生物学功能及筛选CCR6的拮抗剂奠定了基础。     

人FAT10蛋白过表达诱导饥饿状态下HEK 293细胞发生凋亡

目的:采用flag标记的人FAT10蛋白研究人FAT10蛋白对HEK293细胞的影响。方法:将FAT10基因片段克隆到载体pcDNA3-flag上,对阳性克隆进行PCR、酶切和测序鉴定,用脂质体转染HEK293细胞,用Western blotting方法检测外源性FAT10正常培养状态和饥饿状态下的HEK293细胞中的表达情况;并用XTT法和DNA ladder法观察正常培养和饥饿状态下HEK293细胞的凋亡情况。结果:重组质粒在HEK293细胞中高效表达,但在正常培养状态下和饥饿状态下表达情况不同。饥饿状态下,过表达FAT10的HEK293细胞存活率显著低于对照细胞,并且出现DNA ladder现象。结论:成功构建了带Flag标签的FAT10真核表达质粒,可在HEK293细胞中高效表达;FAT10过表达促进饥饿状态的HEK293细胞发生凋亡。     

小鼠精子发生相关蛋白3基因在小鼠生精细胞的特异表达及对HEK 293T细胞凋亡和自噬的影响

目的检测小鼠精子发生相关蛋白3(spata3)基因在小鼠生精细胞的表达情况,并借助过表达细胞模型进一步分析该基因对人胚肾HEK 293T细胞凋亡及自噬的影响,旨在探讨spata3在精子发生过程中的意义。方法分别采用RT-PCR和免疫印迹法检测spata3基因mRNA及蛋白产物在小鼠各组织中的表达;应用免疫组织化学和免疫荧光染色观察SPATA3蛋白在生精细胞中的定位;借助脂质体将真核表达载体Plv-EGFP-2(a)purospata3瞬时转染HEK 293T细胞,进一步在蛋白水平分析细胞凋亡相关蛋白Caspase-3、多聚ADP-核糖聚合酶(PARP)、BAX和Bcl-2及自噬相关蛋白LC3A/B的变化。结果 Spata3基因及其编码产物在小鼠睾丸组织特异表达;粗线期精母细胞和圆形精子细胞的胞质与胞核均有显著SPATA3蛋白的阳性着色,长形精子细胞的胞质也有大量分布;过表达spata3的HEK 293T细胞内活化型Caspase-3和PARP降解产物的含量较对照组差异无显著性,BAX表达量0.815±0.020较裸细胞组0.469±0.012和空载体转染组0.588±0.018均有所增高,Bcl-2含量0.214±0.020低于裸细胞0.507±0.021和空载体转染组0.545±0.024,LC3A/B-Ⅱ的表达量0.741±0.037则显著高于裸细胞组0.136±0.011和空载体转染组0.169±0.012。结论 Spata3基因在小鼠生精细胞特异表达,过表达spata3对HEK 293T细胞凋亡无明显影响,但可以促进细胞自噬。     

基于CRISPR/Cas9系统的HEK293T细胞DMD基因第51号外显子的靶向敲除

目的应用CRISPR/Cas9基因编辑技术,完成HEK293T细胞中DMD基因第51号外显子(exon51)高效的靶向敲除。方法设计靶向人DMD基因exon51 5'端及3'端的sgRNA并克隆至CRISPR/Cas9载体质粒PX459中,转染至HEK293T细胞后,提取基因组DNA并使用Surveyor法检测切割活性;使用目标外显子两端切割活性最高的sgRNA构建PX459-2sgRNA质粒,转染至HEK293T细胞后用PCR及T载体测序检测靶向外显子切除情况。结果50%的HEK293T细胞中DMD基因exon51被定向切除,编辑效率较高。结论建立使用CRISPR/Cas9单质粒敲除人DMD基因exon51的平台,为DMD及其他遗传病的基因治疗研究奠定实验基础。     

小鼠FasL基因真核表达载体的构建及在HEK293细胞中的表达

目的构建含有小鼠Fas Ligand(FasL)基因的重组真核表达载体,并检测FasL蛋白在其稳定转染的HEK293细胞中的表达情况,为构建表达小鼠Fas L的树突状细胞(DC)模型,深入研究DC联合T细胞防治移植物抗宿主病(GVHD)的新方法奠定基础。方法从小鼠脾脏中提取RNA并逆转录为cDNA,以该cDNA为模板扩增FasL基因,插入pcDNA3.1(+)载体中构建pcDNA3.1(+)-FasL重组质粒,利用脂质体将其转染HEK293细胞,用G418筛选稳定表达细胞系,Western blot确定重组蛋白的表达。结果通过酶切及测序证实FasL序列正确插入表达载体pcDNA3.1(+),Western blot检测证实转染重组质粒的细胞能正确表达FasL蛋白,G418筛选后能够得到稳定表达FasL的抗性细胞株即FasL-HEK293。结论重组质粒pcDNA3.1(+)-FasL和稳定表达FasL的HEK 293细胞成功构建,为后续FasL-DC细胞的研究打下了坚实基础。     

Effect of morpholino antisense oligonucleotide against lumican mRNA in human embryonic kidney (HEK) 293 cells

Lumican is a member of the small-leucine-rich proteoglycan (SLRP) family and is overexpressed during wound healing of the cornea, in ischemic and reperfused heart, and in several cancer tissues. Lumican is considered to regulate the collagen fibril diameter and interfibrillar spacing. However, the effect of lumican on cell growth has not been adequately examined. In the present study, we attempted to clarify whether lumican contributes to human embryonic kidney (HEK) 293 cell growth, using the morpholino antisense oligonucleotide (m-anti oligo) against lumican mRNA. M-anti oligo is a novel oligonucleotide and exhibits a higher antisense activity, higher water solubility, and greater resistance to nucleases in target cells than phosphorothioate types of oligonucleotide. After delivery of m-anti oligo against lumican mRNA, the fluorescein 5-isothiocyanate (FITC) conjugated oligonucleotides were observed in the cytoplasm and nucleus of HEK 293 cells at 24 h by confocal laser microscopy. M-anti oligo for lumican mRNA strongly inhibited the synthesis of lumican protein in the HEK 293 cells, and the HEK cell growth rate was higher than those in the control groups. These findings may indicate that lumican protein has an inhibitory effect on HEK 293 cell growth in vitro .     

Human embryonic kidney (HEK293) cells express endogenous voltage-gated sodium currents and Nav1.7 sodium channels

Human embryonic kidney (HEK293) cells are widely used for the heterologous expression of voltage- and ligand-gated ion channels. Patch clamp analysis of HEK293 cells in the whole-cell configuration identified voltage-gated, rapidly inactivating inward currents. Peak current amplitudes ranged from less than 100 pA to more than 800 pA, with the majority (84 of 130 cells) in the 100–400 pA range. Transient inward currents were separated into three components on the basis of sensitivity to cadmium and tetrodotoxin (TTX). Application of cadmium (300 μM) reduced current amplitude to 65% of control, consistent with the existence of current carried by a cadmium-sensitive nonspecific cation channel previously identified in HEK293 cells. Application of TTX (500 nM) reduced current amplitude by 47%, consistent with the existence of current carried by a TTX-sensitive voltage-gated sodium channel. Joint application of cadmium and TTX was additive, reducing current amplitude to 28% of control. The residual cadmium- and TTX-resistant currents represent a third pharmacologically distinct component of the rapidly inactivating inward current that was not characterized further. The pyrethroid insecticide tefluthrin (10 μM) prolonged the inactivation of transient currents and induced slowly decaying tail currents, effects that are characteristic of sodium channel modification by pyrethroids. The use of sodium channel isoform-specific primers in polymerase chain reaction amplifications on HEK293 cell first-strand cDNA detected the consistent expression of the human Na_v1.7 sodium channel isoform in cells that expressed the TTX-sensitive component of current. These results provide evidence for an endogenous TTX-sensitive sodium current in HEK293 cells that is associated primarily with the expression of the Na_v1.7 sodium channel isoform.     

FBXO6基因真核表达载体的构建及其在HEK293T细胞中的表达

目的 构建F盒蛋白6(FBXO6)基因真核表达载体.方法 采用PCR方法合成含有EcoR Ⅰ和Bgl Ⅱ双酶切位点的FBXO6 cDNA全长.分别构建载体pEGFP-C1-FBXO6和pEGFP-C1-anti-FBXO6,采用菌落PCR、双酶切鉴定以及测序证实cDNA片段大小和序列正确.将载体pEGFP-C1-FBXO6和pEGFP-C1-anti-FBXO6分别转染HEK293T细胞,Western blot法检测FBXO6蛋白的表达.结果 pEGFP-C1-FBXO6和pEGFP-C1-anti-FBXO6包含大小、序列正确的FBXO6片段;FBXO6蛋白在转染pEGFP-C1-FBXO6的293T细胞中高表达;在转染pEGFP-C1-anti-FBXO6的HEK293T细胞中表达降低.结论 成功构建FBXO6基因正义真核表达载体pEGFP-C1-FBXO6和反义真核表达载体pEGFP-C1-anti-FBXO6.     

Expression and Membrane Association of Hepatitis C Virus Envelope 1 Protein

The expression of hepatitis C virus (HCV) E1 protein is toxic for Escherichia coli cells. For this reason, we have cloned the E1 gene in the pET3a vector and analyzed the inducible expression of the protein in two strains of E. coli characterised by a different level of reduction of basal synthesis. The results indicated that synthesis of E1 was supported only by the BL21(DE3)pLysS strain which provides a tightest control of protein expression before the induction. The BL21(DE3)pLysS cells were then used for the expression of E1 gene, varying at its carboxy terminus in order to retain (E1, aa 192–383) or delete (E1t, aa 192–340) a C-terminal hydrophobic region that may be involved in membrane association. Following cell fractionation, E1 protein was found associated with the membrane fraction. By contrast, the truncated mutant E1t, was identified in the soluble phase suggesting a direct role for the C-terminal domain in E1 membrane association.     

蛋白酪氨酸磷酸酶SHP-2对去血清培养诱导的293T细胞凋亡的作用

目的：探讨蛋白酪氨酸磷酸酶SHP－2对去血清培养诱导人胚肾293T细胞凋亡的作用。方法:将pIRES-GFP空载体、pIRES-GFP-SHP-2(WT)野生型及pIRES-GFP-SHP-2C459S突变体通过脂质体法转染293T细胞，MTT测定去血清培养对293T细胞增殖的抑制情况，去血清培养293T细胞3 d后，电镜观察超微结构、流式细胞仪检测细胞凋亡率、免疫组织化学方法测定caspase-3表达。结果:去血清培养293T细胞3 d，转染pIRES-GFP-SHP-2(WT)野生型组的293T细胞凋亡率明显低于对照组和pIRES-GFP-SHP-2C459S突变体组；而2转染组超微结构均发生早期凋亡，但并无明显差异；caspase-3免疫组化结果显示SHP-2(WT)野生型组的caspase-3表达率明显低于SHP-2C459S突变体组。结论:SHP-2可能参与到去血清培养诱导细胞凋亡的信号转导通路中并通过caspase-3依赖途径，对细胞的生存起到正向调节作用。     

小鼠微小RNA miR-21真核表达载体构建及其在293细胞的活性表达

目的构建小鼠微小RNA miR-21的真核表达载体,在人胚肾293细胞中验证其活性表达,为进一步以此载体研究miR-21的功能打下基础。方法根据小鼠miR-21的成熟序列及其上下游约170 bp的序列设计引物,利用PCR技术从小鼠基因组DNA扩增含有miR-21前体的片段382 bp,克隆到质粒pRc/CMV,对重组质粒经双酶切及测序分析,鉴定完全正确后转染人胚肾293细胞,G418(1 000 mg/L)筛选后获得miR-21稳定表达细胞系,Northern blot验证其在293细胞的过表达;同时构建pmiR-21-Luc reporter荧光素酶报告质粒,与miR-21重组质粒共转染293细胞进行荧光素酶活性分析,验证其调控活性。结果成功构建小鼠miR-21的真核表达载体,其可以在293细胞中稳定高效表达,荧光素酶活性实验证实其有生物活性。结论成功构建小鼠miR-21的真核表达载体,为进一步探讨miR-21的生物学功能奠定了实验基础。     

AR-GFP融合基因真核表达载体的构建及在HEK293细胞中的表达

目的：构建由绿色荧光蛋白（GFP）标记的人醛糖还原酶（AR）融合基因真核表达载体并在HEK293细胞中表达。 方法:应用DNA重组技术构建AR与GFP的融合基因（AR-GFP），将AR-GFP插入pcDNA3.1/myc-HisA真核表达载体中，通过磷酸钙共沉淀转染HEK293细胞，倒置荧光显微镜评价转染效率，Western blotting 技术检测AR基因在转染细胞中的整合及表达，分光光度法（UV法）测定AR表达活性，用公认的AR抑制剂（ARI）反证活性AR的存在。结果:荧光显微镜对转染细胞的观察及Western blotting 结果证实AR-GFP融合蛋白在HEK293细胞中表达，UV法测活、ARI抑制试验均未证实其生物学活性。 结论:转染的HEK293细胞可成功地表达AR-GFP融合蛋白，但不能成为ARI真核细胞筛选模型。     

野生型和突变型GDF5蛋白表达及亚细胞定位的研究

目的研究人生长分化因子5基因(GDF5)c.1118T>G(p.L373R)突变对GDF5蛋白在HEK-293细胞系表达及其亚细胞定位的影响。方法构建pDsRed1-N1-GDF5-WT和pDsRed1-N1-GDF5-L373R载体,分别转染HEK-293细胞,细胞培养72h后通过荧光显微镜观察比较野生型和突变型GDF5蛋白荧光分布情况。结果 GDF5蛋白在HEK-293细胞中成功表达,在荧光显微镜下观察到转染野生型和突变型GDF5的细胞胞浆均匀发出红色荧光,而空载体组的红色荧光则弥散于全细胞,荧光强度均匀一致。结论野生型和突变型GDF5蛋白均定位于HEK-293细胞质。     

Increased Locomotor Activity and Non-Selective Attention and Impaired Learning Ability in SD Rats after Lentiviral Vector-Mediated RNA Interference of Homer 1a in the Brain

Our previous studies found that Homer 1a, a scaffolding protein localized at the post-synaptic density (PSD) of glutamatergic excitatory synapses, is significantly down-regulated in the brain of spontaneous hypertensive rats (SHR), an animal model of attention deficit hyperactivity disorder (ADHD). Furthermore, a first-line treatment drug for ADHD, methylphenidate, can up-regulate the expression of Homer 1a. To investigate the possible role of Homer 1a in the etiology and pathogenesis of ADHD, a lentiviral vector containing miRNA specific for Homer 1a was constructed in this study. Intracerebroventricular injection of this vector into the brain of Sprague Dawley (SD) rats significantly decreased Homer 1a mRNA and protein expression levels. Compared to their negative controls, these rats displayed a range of abnormal behaviors, including increased locomotor activity and non-selective attention and impaired learning ability. Our results indicated that Homer 1a down-regulation results in deficits in control over behavioral output and learning similar to ADHD.     

大鼠GLUT1真核表达载体的构建及其在293细胞中的表达

目的：构建大鼠葡萄糖转运体1（GLUT1）的真核表达载体。 方法： 以RT-PCR方法从大鼠脑组织中获取GLUT1全长cDNA片段，将其克隆至真核表达质粒pcDNA3.1(+)中，构建重组真核表达质粒pcDNA3.1(+)-Glut1，随后用lipofectamineTM 2000介导转染HEK293细胞，以RT-PCR法检测重组质粒在mRNA水平的表达，以免疫组化的方法检测重组质粒在蛋白水平的表达。 结果： 以构建的重组真核表达质粒pcDNA3.1(+)-Glut1转染293细胞后，在基因及蛋白表达水平均检测到了葡萄糖转运体1的表达。 结论： 成功构建了携带大鼠葡萄糖转运体1的真核表达载体pcDNA3.1(+)-Glut1，且证实其可在293细胞中成功表达目的基因，为进一步研究外源性GLUT1表达对缺血缺氧脑细胞的保护作用奠定了基础。     

Transport properties of the human intestinal anion exchanger DRA (down-regulated in adenoma) in transfected HEK293 cells

Electroneutral NaCl absorption in the intestine is mediated by parallel Na+/H+ and Cl-/HCO3- exchange. Mutations in the down-regulated in adenoma (DRA) gene cause congenital chloride diarrhoea but the transport characteristics of human DRA have not been studied in a heterologous human expression system. A N-terminal enhanced green fluorescence protein (EGFP)-tagged human DRA construct was therefore expressed stably in HEK293 cells. Cl-/HCO3- exchange was assessed by measuring intracellular pH and intracellular Cl- using fluorescent dyes. Expression of DRA resulted in the appearance of EGFP fluorescence and DRA immunoreactivity consistent with a location in the plasma membrane and possibly structures below the plasma membrane. DRA mediated electroneutral Cl-/HCO3- exchange but OH- was not transported and SO4(2-)/HCO3- exchange was minimal. In the presence of 5% CO2/HCO3- the apparent affinity of DRA for Cl- in transfected HEK cells was 23-36 mM, which is lower than that reported for rabbit ileal brush border membrane vesicles and for oocytes injected with human DRA. DRA was inhibited by 4 mM DIDS (45+/-11%), by 50 microM tenidap (71+/-8%) and by 100 microM glibenclamide (59+/-22% inhibition of HCO3- transport and 79+/-3% inhibition of Cl- transport). The effects of DIDS and tenidap were not additive to those of glibenclamide.     

小鼠Islet-1基因慢病毒表达载体的构建及其诱导C_3H_(10)T1/2细胞向心肌样细胞特异性分化

目的研究Islet-1对干细胞分化的影响。方法用PCR钓取目的基因,将目的基因与pLenO-WPI载体连接,选取阳性质粒,与辅助质粒共同感染293T细胞生产出慢病毒载体。感染C3H10T1/2细胞,实时荧光定量PCR及Western blot检测Islet-1和心肌、肝脏、骨骼及神经各系统相关标志物的表达,免疫荧光检测心肌肌钙蛋白T(cTnT)表达部位。结果 PCR及测序显示目的片段正确插入,实验组有Islet-1表达;心肌早期发育相关基因GATA-4、MEF2C、NKx2.5在检测到荧光蛋白1周后升高,2周到达高峰,3周后可检测到心肌特异性蛋白cTnT(0.582±0.0576),其时序性表达呈随时间增强趋势;cTnT表达于胞质;肝脏系统特异性标志AFP及ALB、骨骼系统特异性标志BGP及BALP、神经系统特异性标志Nestin及GFAP均未表达。结论 Islet-1具有特异性促进干细胞向心肌样细胞分化的作用。