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1.
诱生型一氧化氮合酶基因启动子的结构及其调控   总被引:3,自引:0,他引:3  
鼠类NOS2基因5′端1.7kb序列几乎包含了所有的顺式作用元件,其中NFκB结合位点,IRF-RE,CAATbox和GAS4等元件对该在的诱导性转录调控至关重要,人NOS2基因5′端3.7kb范围与鼠类有相似的调控元件,但该区域仅有基础启动子活性,其诱导性调控元件在-3.7kb的上游,其中NFκB结合位点着关键的作用。  相似文献   

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人GM—CSF cDNA的克隆和在大肠杆菌中的表达   总被引:3,自引:0,他引:3  
从诱导的人胚肺细胞HFL株中提取总RNA.经RT-PCR反应获取了人GM-CSFcDNA,DNA序列测定表明其顺序与文献报道完全一致。为了获得高效表达,应用PCR改造了人GM-CSF的cDNA5’端核苷酸序列,并将改造的人GM-CSF基因插入含T7启动子的质粒pET-11d构建成表达质粒pETC-5,将此质粒转化大肠杆菌株BL21(DE3)得到表达菌株BLEC4。表达菌株用0.5mol/LIPTG诱导2小时后,产生大量重组蛋白并形成包涵体。SDS—PAGE电泳图谱扫描结果表明,rhGM-CSF产量占菌体总蛋白量的16%。ELISA和TF-1细胞培养测定表明,初步纯化和复性的rhGM-CSF具有天然的hGM-CSF生物活性。  相似文献   

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用丙型肝炎病毒重组蛋白C33_c抗原免疫BALB/c小鼠,运用杂交瘤技术成功地建立了7株能稳定分泌抗C33_c单克隆抗体的杂交瘤细胞1H6D2、2G1A6、3A4A8、3E3E7、4G12C10、4A10C2、5F4B6.试验结果表明,7株McAbs具有良好的HCV特异性,间接ELISA法测得小鼠腹水McAb效价为1:10 ̄4-1:4×10 ̄4;竞争抑制实验和相加指数测定证实7株McAbs识别相关的抗原表位;7株McAbs中1株为IgM(5F4B6),其它6株为IgG(2a)。  相似文献   

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用原位杂交法及激光光密度计灰度扫描半定量法,比较了老年组(24月龄)与青年组(6周龄)Wistar大鼠离体培养的主动脉VSMC(5-10代)c-myc与HSP70基因的表达及红细胞抗高血压因子(AHF)、去甲肾上腺素(NE)与人参皂甙对上述基因表达的影响。结果表明:1.增龄导致的VSMC增殖很可能与c-myc基因的过度表达有关,NE、AHF和人参皂甙可以通过调控c-myc基因的表达来影响VSMC增殖。2.增龄伴随的应激能力下降可能与HSP70基因表达的减少有关。3.HSP70基因也可能参与了VSMC增殖与分化的调控,NE、AHF与人参皂甙可能通过调控HSP70基因的表达来影响VSMC的增殖  相似文献   

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利用PCR扩增得到粒细胞-巨噬细胞集落刺激因子(GM-CSF)、白细胞介素-3(IL-3)完整基因片段,将其分别克隆pGEM-T构建成GM-CSF/IL-3融合蛋白基因,DNA序列与设计预期一致。将得到的融合蛋白基因克隆对72RNA聚合酶表达载体pT7zz,得到表达质粒pFu,经转化至表达宿主E.coli BL21(DE3),在IPTG诱导下获得融合蛋白目的产物的直接表达。经SDS-PAGE电泳鉴  相似文献   

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报道了弹性蛋白亲和层析分离弛化芳香黄杆菌产胞外弹性蛋白酶,经一步柱层析可获聚丙烯酰胺凝胶电泳均一的酶制品,收率可达50%,并制备了酶的结晶。该酶在SDS-PAGE上测得分子量为21380,EF-PAGE测得等电点8.9最适作用温度为50℃,最适作用,PH为7.4在40℃以下热稳定性良好,PH4.5-9.5范围内稳定,重金属离子Fe^3+,Zn^2+,Co^2+,Hg^2+,Ni^2+Ag^+,Cu  相似文献   

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在克隆了人基因组全长vigilin基因的基础上,对其5端转录调控区域再克隆,获得Vig-CG5-7E克隆,再用限制酶ApaⅠ和EcoRⅠ切除3端约4kb部分,得到Vig-CG5-7E3AE克隆,并对该克隆进行双向测序分析.结果表明:克隆Vig-CG5-7E用ApaⅠ酶消化后,用cDNA上游开始的20个碱基组成的寡聚核苷酸做探针进行分子杂交,可见一条小于0.1kb杂交带,根据物理图谱分析,位于Vig-CG5-7E3AE克隆的ApaⅠ端,从而推断该克隆含有转录调控元件,5端序列分析得到二个TATA盒,一个CAAT盒和一个GC盒以及二个可能的Ap-1和Ap-2结合位点.认为GC盒可能为人vigilin基因启动子的组成部分  相似文献   

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地塞米松(Dex)、噻庚啶(Cyp) 和山莨菪碱(Ani) 对脂多糖(LPS) 诱导的大鼠肝脏TNFα表达的影响。Wistar大鼠40 只, 静脉注射LPS(EcoliO111B4 5m g/kg) 后, 立即静脉给予Dex 5m g/kg、Cyp5m g/kg 或Am i10m g/kg,于LPS攻击后2h 取动物的肝脏,APAAP法进行TNFα免疫组织化学研究,North-ern 杂交分析TNFαm RNA 表达水平。结果发现LPS攻击后2h, 肝脏TNFαm RNA 表达水平显著增高, 肝脏枯否氏细胞胞浆内有大量的TNFα红染颗粒。Dex、Cyp 或Ani均能显著降低大鼠肝脏TNFαm RNA 水平和TNFα含量。结果表明Dex、Cyp 和Ani均显著抑制LPS诱导的TNFα基因表达, 可能有抗感染性休克作用。  相似文献   

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利用COS7细胞暂时表达系统,研究转译起始序列对EPO-cDNA表达的影响。通过DNA重组技术,构建了原EPO-cDNA表达载体pCSV-EPO(1),其转译起始序列为5'AATTCATGG3'。同时通过定点突变技术,将起始序列改变成5'CCACCATGG3',而构建了另一表达载体PCSV-EPO(2)。后经序列分析证明无误后和前均通过DEAE-dextran法转染COS7细胞上清,测定结果为  相似文献   

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利用人粒细胞集落刺激因子(hG-CSF)cDNA3′端非翻译区(3′-UTR)中存在的DraⅠ酶切位点,通过部分酶切与完全酶切,删除3′-UTR不同长度,构建了四种hG-CSFcDNA瞬时重组表达质粒。转染COS-7细胞后,生物活性测定结果提示,hG-CSFcDNA3′-UTR对其表达起负调控作用,其关键性序列位于紧接终止密码子TGA下游的65bp范围内,3′-UTR对hG-CSFcDNA表达的影响与转录水平的差别有一定关系。  相似文献   

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In experiments on Black Sea skates (Raja clavata), the potential of the receptor epithelium of the ampullae of Lorenzini and spike activity of single nerve fibers connected to them were investigated during electrical and temperature stimulation. Usually the potential within the canal was between 0 and –2 mV, and the input resistance of the ampulla 250–400 k. Heating of the region of the receptor epithelium was accompanied by a negative wave of potential, an increase in input resistance, and inhibition of spike activity. With worsening of the animal's condition the transepithelial potential became positive (up to +10 mV) but the input resistance of the ampulla during stimulation with a positive current was nonlinear in some cases: a regenerative spike of positive polarity appeared in the channel. During heating, the spike response was sometimes reversed in sign. It is suggested that fluctuations of the transepithelial potential and spike responses to temperature stimulation reflect changes in the potential difference on the basal membrane of the receptor cells, which is described by a relationship of the Nernst's or Goldman's equation type.I. P. Pavlov Institute of Physiology, Academy of Sciences of the USSR, Leningrad. I. M. Sechenov, Institute of Evolutionary Physiology and Biochemistry, Academy of Sciences of the USSR, Leningrad. Pacific Institute of Oceanology, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Neirofiziologiya, Vol. 12, No. 1, pp. 67–74, January–February, 1980.  相似文献   

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Evolution of living organisms is closely connected with evolution of structure of the system of regulations and its mechanisms. The functional ground of regulations is chemical signalization. As early as in unicellular organisms there is a set of signal mechanisms providing their life activity and orientation in space and time. Subsequent evolution of ways of chemical signalization followed the way of development of delivery pathways of chemical signal and development of mechanisms of its regulation. The mechanism of chemical regulation of the signal interaction is discussed by the example of the specialized system of transduction of signal from neuron to neuron, of effect of hormone on the epithelial cell and modulation of this effect. These mechanisms are considered as the most important ways of the fine and precise adaptation of chemical signalization underlying functioning of physiological systems and organs of the living organism  相似文献   

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