SARS-CoV基因重组质粒的构建与表达

目的　针对SARS冠状病毒 (SARS CoV)M、N、S和E蛋白 ,构建 4种重组真核表达质粒pVAX1 M、pVAX1 N、pVAX1 S和pVAX1 E ,为研制SARSDNA疫苗奠定基础。方法　根据GenBank中SARS病毒基因序列分别设计M、N、S和E引物 ,用RT PCR方法从感染SARS病毒的Vero E6细胞中扩增得到M、N、S和E片段 ,构建重组质粒pVAX1 M、pVAX1 N、pVAX1 S和pVAX1 E。并以重组质粒转染COS 7细胞 ,用免疫细胞化学和Westernblot方法鉴定重组质粒体外的表达。结果　经酶切鉴定及DNA序列测定证实重组质粒构建正确 ,细胞转染实验表明 ,构建的 4种重组质粒均能在COS 7细胞内表达。结论　成功构建 4种SARS CoV 4种蛋白抗原真核表达质粒 ,并能在真核细胞内获得表达。     

酸敏感离子通道基因重组质粒的构建、表达及其活性测定

为了构建含有小鼠酸敏感离子通道(ASIC1a、ASIC2a)基因全长cDNA的重组质粒,并表达有生物学活性的ASIC1a和ASIC2a融合蛋白,本研究通过逆转录聚合酶链反应(RT-PCR)分别获得小鼠ASIC1a和ASIC2a全长cDNA,并将其克隆入真核表达载体pEGFP-N3中,构建含小鼠全长ASIC1a和ASIC2a基因的重组质粒pEGFP-ASIC1a和pEGFP-ASIC2a,经DNA测序鉴定序列正确。脂质体法分别将其转染至中国仓鼠卵巢细胞(CHO),荧光显微镜下观察小鼠ASIC1a和ASIC2a融合蛋白在细胞内的表达分布,Westernblot检测其蛋白表达。酸性处理转染重组质粒细胞,并比较其细胞存活率及乳酸脱氢酶(LDH)的释放来评价融合蛋白的生物学活性。结果显示:本研究成功地分别将小鼠ASIC1a和ASIC2a全长cDNA克隆入pEGFP-N3载体中,并将其转染至CHO细胞,荧光显微镜下观察到CHO细胞膜周围呈强绿色荧光条带,Westernblot显示小鼠ASIC1a和ASIC2a融合蛋白分别在90kD和88kD处有表达。经酸性处理的转染ASIC1a和ASIC2a重组质粒的CHO细胞,分别较其在pH7.4条件下的细胞存活率明显降低,LDH释放量明显增高,且通道阻断剂可抑制该效应。上述结果提示,我们已成功构建出含小鼠ASIC1a和ASIC2a全长cDNA的重组质粒pEGFP-ASIC1a和pEGFP-ASIC2a,并使有生物学活性的ASIC1a和ASIC2a融合蛋白在CHO细胞中表达。     

NOX4报告基因重组质粒的构建及表达调控初探

目的：构建NOx4荧光素酶报告基因质粒载体,探讨NOX4基因表达调控机制。方法：以细胞基因组DNA为模板作,采用PCR扩增NOX4基因上游调控序列（533bp）,插入质粒DGL3-basic载体,构建重组质粒pGL3-NOX4,重组质粒经酶切和测序鉴定。将pGL3-NOX4转染A549细胞,通过细胞因子刺激观察报告基因表达水平。结果：酶切及测序证实NOX4报告基因质粒构建成功。转染报告基因的A549细胞以细胞因子刺激,结果显示NOx4表达增强。结论：成功构建了NOX4荧光素酶报告基因质粒载体,为进一步研究NOX4基因的表达规律及生理功能奠定了基础。     

杜氏利什曼原虫amastin基因重组真核表达质粒的构建与表达

目的：构建杜氏利什曼原虫无鞭毛体蛋白（alllastin）编码基因的真核表达重组质粒pcDNA3．1-amastin，并研究其在NIH3T3细胞中的表达。方法：提取杜氏利什曼原虫基因组DNA进行PCR扩增。将扩增的无鞭毛体蛋白基因片段导入质粒pcDNA3．1（＋）中，构建真核表达重组质粒pcDNA3．1-amastin。以pcDNA3．1-amastin转染NIH3T3细胞，采用免疫荧光染色法和RT-PCR分别鉴定pcDNA3．1-amastin的瞬时表达和稳定表达。结果：在细胞膜和细胞内均观察到较强的绿色荧光，表明pcDNA3．1-amastin成功地转入NIH3T3细胞，并在细胞膜和细胞内获得短暂表达。稳定转染的NIH3T3细胞的总RNA经反转录后，用PCR扩增出无鞭毛体蛋白基因，表明获得了稳定表达。结论：成功地构建杜氏利什曼原虫无鞭毛体蛋白基因的真核表达重组质粒，并且该基因在NIH3T3细胞中获得了稳定表达。     

人重组pMAGE-A1/EGFP真核表达质粒的构建与表达

目的　特异克隆MAGE A1开放读码框基因,构建以绿色荧光蛋白(EGFP)为报告基因的包含MAGE A1的真核表达载体并转染人PBMC来源DC细胞。方法　根据MAGE A1特征序列设计PCR扩增引物,从Mel 5 2 6中扩增MAGE A1基因开放读码框,并克隆至pIRES EGFP中,构建人重组pMAGE A1 EGFP真核表达质粒。利用电转染方法将该重组质粒转入人外周血来源DC细胞并检测MAGE A1和EGFP的表达情况。结果　成功构建真核表达质粒pMAGE A1 EGFP ,转染人PBMC来源DC细胞并检测到MAGE A1和EGFP表达,两者表达率分别为(8.8±0 .9) %和(8.4 7±0 .78) % ,无统计学差异。结论　成功构建人重组真核表达质粒pMAGE A1 EGFP ,为开展MAGE A1为基础的免疫治疗提供有利的分子生物学工具。     

HMGN2的重组表达质粒的构建及其抗菌功能研究

目的：构建HMGN2重组表达栽体,探讨HMGN2分子抗菌作用。方法：用基因克隆的方法构建pET-32a-c（＋）-HMGN2重组表达质粒,经IPTG诱导表达后,用亲和层析的方法纯化His-HMGN2融合蛋白,Tricine-SDS-PAGE电泳鉴定其分子量,行琼脂糖弥散法检测其抗菌功能。结果：成功构建了pET-32a-c（＋）-HMG17重组表达质粒,其表达的融合蛋白对致病性大肠杆菌54080,54299以及金黄色葡萄球茼ATCC25923均有抗菌活性。结论：HMGN2是一种抗菌分子,可能参与了体内的天然免疫防御作用。     

hBDNF基因原核表达重组质粒的构建及其在大肠杆菌中的表达

我们按照hBDNF基因全长编码序列设计合成引物,从人基因组DNA中扩增出760bp的片段,反向插入到pGEM-3Zf( )载体上,获得pGEMBF18克隆,限制性酶分析和DNA序列测定均证实该克隆插入片段为hBDNF基因全长编码序列。从pGEMBF18克隆中获取hBDNF全长编码片段,与原核表达载体pGEX-5T连接,构建了p5TBF34原核表达重组质粒。重组质粒转化大肠杆菌JM109,经IPTG诱导表达,SDS-PAGE特异区带分子量为43kDa,此重组蛋白占菌体可溶性蛋白总量的7.53%,Western杂交证实该特异区带具hBDNF抗原活性。     

pEGFP-N1-PGC-1α重组质粒的构建及体外表达

目的 构建PGC-1α真核表达载体pEGFP-N1-PGC-1α重组质粒,鉴定及体外表达.方法 通过RT-PCR方法从组织中克隆PGC-1α基因片段,酶切后将其定向插入真核表达载体pEGFP-N1中,构建pEGFP-N1-PGC-1α重组质粒.结果 双酶切法、测序法鉴定表明目的基因正确插入质粒.结论 成功构建了pEGFP-N1-PGC-1α真核表达载体,转染huh-7细胞后,可瞬时、有效表达,为进一步研究PGC-1α调节HBV、HPV生物合成奠定了基础.     

重组质粒pEGFP-Brn-4的构建及其在神经干细胞中的表达

目的构建神经发育转录因子Brn-4基因真核表达重组质粒,研究Brn-4在神经干细胞(NSC)中的表达情况。方法从新生鼠脑组织提取总RNA,利用RT-PCR的方法获得编码鼠Brn-4的基因片段,应用基因重组技术,将鼠Brn-4基因片段克隆到真核表达载体pEGFP-C2中,应用脂质体转染NSC,荧光显微镜观察该Brn-4基因在NSC中的表达。结果限制性内切酶酶切分析和PCR法鉴定表明为正确重组子,Brn-4基因在NSC中获得表达。结论新构建的真核表达重组质粒pEGFP-Brn-4通过鉴定,结构正确;Brn-4基因可在NSC中表达,可作为后续研究老年性痴呆动物模型转基因实验的基因来源。     

HBsAg逆转录病毒表达质粒的构建及其在真核细胞中的表达

目的 构建乙型肝炎表面抗原(HBsAg)逆转录病毒表达质粒并探讨其在真核细胞中的表达。方法 用限制性内切酶从重组质粒pBKS—S中切出HBsAg基因，并亚克隆到逆转录病毒表达质粒pLXSN，构建成重组质粒pLXSN—S；经限制性内切酶消化和DNA序列测定鉴定无误后，用阳离子脂质体转染法将重组质粒pLXSN—S分别转染HepG2、K562和EB病毒转化B淋巴母细胞(EBVC)；用ELISA法检测HBsAg在细胞培养上清中的表达。结果 经酶切和DNA序列测定鉴定证实重组质粒构建正确；质粒pLXSN—S转染细胞培养上清均可检测到HBsAg。结论 逆转录病毒表达质粒pLXSN—S构建成功并可在真核细胞中稳定表达。     

Recombinant Human Mullerian Inhibiting Substance Inhibits Epidermal Growth Factor Receptor Tyrosine Kinase

Abstract

Autophosphorylation of the epidermal growth factor (EGF) receptor in A-431 cells and plasma membrane fractions was inhibited by partially purified recombinant human Mullerian Inhibiting Substance (MIS). Immunoprecipitation of the EFG receptor using anti-EGF receptor or anti-phosphotyrosine antibodies, and phosphoamino acid analysis of this receptor, demonstrated that MIS specifically inhibited EGF-induced tyrosine phosphorylation. Inhibition of EGF receptor autophosphorylation by MIS in membrane preparations was not affected by increasing concentrations of EGF, manganese or [γ-(32)P] ATP. Thus, it is unlikely that MIS competes for EGF binding sites or sequesters substrate. Immunoabsorption of MIS with anti-human MIS antibody blocked the MIS inhibition of EGF receptor autophosphorylation, indicating that the inhibition was due to MIS. Our data suggest that MIS regulates the activity of the EGF receptor tyrosine kinase in A-431 cells.     

重组平滑肌肌球蛋白轻链激酶及ATP结合位点突变体的构建及表达

目的 构建重组全长平滑肌肌球蛋白轻链激酶(myosin light chain kinase,MLCK)ATP结合位点突变体,以研究平滑肌MLCK的结构与功能.方法 利用试剂盒对MLCK ATP结合位点进行定点突变,构建全长平滑肌MLCK ATP结合位点突变体重组表达载体pCold/BsMLCK/△ATP,在大肠杆菌中表达:利用SDS-PAGE鉴定表达的重组全长平滑肌MLCK ATP结合位点突变体在细胞中的分布:运用亲和层析及凝胶过滤分离纯化重组全长MLCK并利用SDS-PAGE鉴定表达MLCK的纯度.结果 重组全长MLCK/△ATP(突变型)在大肠杆菌中以可溶的形式大量表达;在样品的上清和沉淀中均有重组全长MLCK/△ATP表达;经CaM-Sepharose 4B和Superose 6 HR纯化,SDS-PAGE鉴定得到单一的表达条带.结论 重组全长MLCK/△ATP(突变型)可以在大肠杆菌中以可溶形式大量表达;SDS-PAGE结果显示重组全长MLCK/△ATP可以通过亲和层析和凝胶过滤纯化得到单一的条带.     

The Role of the Tec Kinase Bruton's Tyrosine Kinase (Btk) in Leukocyte Recruitment

Recruitment of leukocytes into inflamed tissue is a key component of the immune system. The activation of integrins on leukocytes is required for their recruitment into the inflamed tissue. Btk is a cytoplasmic nonreceptor tyrosine kinase belonging to the Tec-kinase family. It plays a key role in B-cell development and function, and recently published studies revealed important roles of Btk in myeloid cells. Btk might be activated through a variety of receptors leading to activation of integrins as the pivotal element in leukocyte recruitment. This review focuses on the role of Btk in B-lymphocyte homing and in neutrophil recruitment.     

Expression of KIT Receptor Tyrosine Kinase in Endothelial Cells of Juvenile Brain Tumors

KIT receptor tyrosine kinase is expressed in tumor endothelial cells of adult glioblastomas, but its expression in pediatric brain tumor endothelial cells is unknown. We assessed expression of KIT, phosphorylated KIT, stem cell factor (SCF) and vascular endothelial growth factor receptor-2 (VEGFR-2) in 35 juvenile pilocytic astrocytomas and 49 other pediatric brain tumors using immunohistochemistry, and KIT messenger RNA (mRNA) using in situ hybridization. KIT and phospho-KIT were moderately or strongly expressed in tumor endothelia of 37% and 35% of pilocytic astrocytomas, respectively, whereas marked SCF and VEGFR-2 expression was uncommon. KIT mRNA was detected in tumor endothelial cells. Tumor endothelial cell KIT expression was strongly (P < 0.01) associated with endothelial cell phospho-KIT and SCF expression, and with tumor KIT (P = 0.0011) and VEGFR-2 expression (P = 0.022). KIT and phospho-KIT were present in endothelia of other pediatric brain tumors, notably ependymomas. Endothelial cell KIT expression was associated with a young age at diagnosis of pilocytic astrocytoma or ependymoma, and it was occasionally present in histologically normal tissue of the fetus and children. We conclude that KIT is commonly present in endothelial cells of juvenile brain tumors and thus may play a role in angiogenesis in these neoplasms.     

Small Tyrosine Kinase Inhibitors as Key Molecules in the Expression of Metalloproteinases by Solid Tumors

Critical steps for cancer cell growth, migration, invasion, and metastasis are the interactions of extracellular matrix (ECM) molecules with cells, the disconnection of intercellular adhesion, and the degradation of ECM. The latter is mediated mainly by metalloproteinases (MMPs), the expression and activation of which is related to various tyrosine kinase receptors (RTKs). The aberrant RTK activity is associated with the development and progress of various human cancers. Tyrosine kinase inhibitors (TKIs) are small molecules which compete with ATP for binding to the kinase domain of the RTKs and have been used for the treatment of solid tumors. In this review, the recent advances of the effects of TKIs on MMPs expressed by solid tumors are presented.     

重组pEGFP-hSnu114质粒的构建及表达

目的 将hSnu114基因定向连入pEGFP质粒GFP的下游,使hSnu114蛋白可与绿色荧光蛋白在真核细胞内融合表达.从而为进一步研究hSnu114蛋白的功能奠定实验基础.方法 本实验已经构建PTZ57R/T –hSnu114和pcDNA3.1(-)-hSnu114重组质粒,想要构建pEGFP-hSnu114重组质粒,需通过引入SalⅠ酶切位点,调整N端起始密码子与绿色荧光蛋白(green fluorescence protein,GFP)基因之间的序列,使其不破坏读码框,融合蛋白正确表达.PCR扩增出hSnu114的第一部份 (SalⅠ～MunⅠ基因序列),从 hSnu114-pcDNA3.1(-)重组质粒回收hSnu114的第二部分(MunⅠ～BamHⅠ片段),定向克隆至T/A载体,构建hSnu114全长(SalⅠ～BamHⅠ)pTZ57R/T重组质粒.采用SalⅠ和BamHⅠ双酶切方法,从重组质粒中获得hSnu114全长,将该基因片段连接入pEGFP质粒.将构建成功的pEGFP-hSnu114质粒,转染入HeLa细胞,荧光显微镜下可观察绿色荧光蛋白表达.进行Western印迹检测.结果 ① hSnu114 SalⅠ～MunⅠ目的片段获取.②将该pEGFP-hSnu114质粒进行双酶切鉴定可见hSnu114全长片段.③转染重组质粒后可观察到绿色荧光蛋白的表达.④ Western印迹可检测到pEGFP-hSnu114融合蛋白.结论 ① hSnu114全长成功载入pEGFP质粒.② hSnu114蛋白可与绿色荧光蛋白在真核细胞中融合表达.     

重组Pegfp-C2-PSF质粒的构建及表达

目的 将人类PSF基因定向连人pEGFP-C2质粒,使PSF蛋白可与绿色荧光蛋白在HeLa细胞内融合表达,为进一步研究PSF蛋白的功能及定位奠定实验基础.方法 采用EcoRⅠ和SalⅠ双酶切方法,从pGEX-2TK-PSF质粒中获得PSF蛋白的cDNA全长;连入pEGFP-C2质粒的C端.将构建成功的pEGFP-C2-PSF质粒转染人HeLa 细胞,荧光显微镜下观察绿色荧光蛋白表达.结果 ①将该质粒进行双酶切鉴定可见PSF片段;②转染重组质粒后可观察到绿色荧光蛋白的表达.结论 ① PSF cDNA全长成功连入pEGFP-C2质粒;② PSF蛋白可与绿色荧光蛋白在HeLa细胞中融合表达.     

Clinical Potential of Targeting Bruton's Tyrosine Kinase

Targeting Bruton's tyrosine kinase (BTK) with a small-molecule inhibitor may be useful in treatment of BTK-expressing malignancies because of the antiapoptotic function of BTK in cancer cells. Furthermore, BTK inhibitors also exhibit antithrombotic properties, which may be desirable in the context of the increased risk of thromboembolic complications in cancer patients. This review will focus on the role of BTK in drug resistance in cancer, thromboembolism, and various pathologic immune responses, such as graft-versus-host disease. The therapeutic potential of targeting BTK is illustrated by discussion of the biologic activity profile of the rationally designed BTK inhibitor LFM-A13.     

APC11基因真核表达质粒构建及鉴定

目的 克隆扩增APC11开放阅读框基因片段,构建其真核表达重组质粒,为后续研究其功能做准备.方法 按照GenBank中人APC11序列设计引物,以HeLa细胞cDNA为模板,扩增出基因片段.该片段与真核表达载体pEGFP-C1连接,得到的重组质粒经双酶切和测序鉴定后用Western印迹检验表达.结果 扩增片段长度为285 bp,重组真核表达质粒经双酶切鉴定后测序鉴定正确.Western印迹证实pEGFP-C1-APC11在真核细胞内表达.结论 成功克隆了APC11基因并构建了pEGFP-C1-APC11真核表达重组质粒,Western印迹证实其表达良好,对该基因功能的深入研究打下了坚实基础.