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为了提高长效组织纤溶酶原活剂(LAtPA)在转基因小鼠乳腺中的表达水平,将受控于羊β-乳球蛋白(BLG)的LAtPA表达载体BLG-LAtPA与小鼠乳清酸蛋白(WAP)基因片段进行共注射,采用此方法建立的转基因小鼠,经PCR筛选和Southern印迹鉴定,获得3只LAtPA和WAP共整合阳性鼠,并在阳性母鼠乳汁中检测到有溶纤活性的LAtPA表达,表达水平达到10μg/mL。 相似文献
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组织纤溶酶原激活剂(tPA)是一种较理想的溶血栓药物,本研究采用其突变体-长效组织纤溶酶原激活剂(LAtPA)的cDNA作为目的基因,将它插入羊β-乳球蛋白(BLG)基因起始密码之前,使LAtPA的转录、翻译受控于BLG基因的5'、3'序列,再将所构建的BLG-LAtPA用显微注射方法建立转基因鼠,经点杂交筛选和Southern印迹鉴定,获得2只LAtPA基因整合阳性鼠,并在阳性母鼠乳汁中检测到有 相似文献
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通过PCR方法从羊肝总DNA中获得了羊-β乳球蛋白(BLG)基因第一和第二内含子,以羊β-乳球蛋白基因(BLG)5’区5kb为调控序列,构建了乳腺表达组织纤溶酶原激活剂突变体载体。对540枚小鼠受精卵进行显微注射,经PCR和Southern blot检测,获得6只整合有人La-tPA的转基因小鼠,整合率为32%。同时研究了转基因在小鼠体内的表达。Northern blot分析表明,在一些转基因鼠乳 相似文献
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利用所构建的乳腺表达组织纤溶酶原激活剂突变体(La-tPA)载体.对540枚小鼠受精卵进行显微注射,经PCP和Southernblot检测,获得6只整合有人La-tPA转基因小鼠.为了精确研究转基因在小鼠体内的表达,采用RT-PCP方法测定转基因鼠在泌乳期1~20dLa-tPA基因的转录,结果表明,在转基因鼠乳腺的La-tPAmRNA水平在10~15d最高,在20d时降为最低.外源基因在转基因小鼠乳腺的表达规律研究为未来利用转基因动物生产La-tPA提供依据 相似文献
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用羊β-乳球蛋白基因(BLG)5’区5*10^3b(10^3b,旧称kb)为调序列,构建了乳腺表达组织纤溶酶原激活剂突变体载体。对540枚小鼠受精卵进行显微注射,经PCR和Southernblot检测,获得6只整合有人La-tPA的转基因小鼠,整合率为32%。 相似文献
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人组织性纤溶酶原激活物衍生物在大肠杆菌硫氧化还原蛋白融合表达系统中的 总被引:3,自引:0,他引:3
目的:克隆含tPA中355个氨基酸密码子(1-3和176-527氨基酸)的cDNA序列(tPA355),将其在大肠杆菌融合蛋白表达系统中表达,并在体外复性使其具有激活纤溶酶原的生物活性。方法:采用RT-PCR技术从人黑色素瘤细胞Bowes中克隆出tPA355 cDNA,然后在pET32a(+)BL21(DE3)大肠杆菌表达系统中表达,将表达出的融合蛋白Trx-tPA355(Thioredoxin,Trx)包涵体在体外进行变性、复性和纯化以使其具有激活纤溶酶原的生物活性。结果:测序结果表明本研究克隆的编码tPA中355个氨基酸密码子的cDNA序列与美国专利(公开号:5,587,159)中对应的序列完全一致,将其在pET32a(+)/BL21(DE3)大肠杆菌表达系统中表达可获得稳定表达的融合蛋白Trx-tPA35 相似文献
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对从HepG2细胞培养液中分离得到植基化和非糖基化PAI-1(1型纤溶酶原激活物抑制剂),以及从pYZHBI-66表达菌中纯化的非糖基化重组PAI-1的某些性质和功能进行比较,结果显示,糖基化PAI-1对tPA(组织型纤溶酶原激活物)有较强的抑制,能较显著地被蛋白质变性剂所激活,对热有较强的稳定性,糖基化与非糖基化PAI-1在pH2.5-9.0的范围内都相当稳定。纤维蛋白原和肝素能明显提高两者对tPA的抑制作用。 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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N. P. Vesselkin Yu. V. Natochin 《Journal of Evolutionary Biochemistry and Physiology》2010,46(6):592-603
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