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1.
以大鼠成骨肉瘤细胞(UMR106)为模型,研究了表皮生长因子(EGF)对其受体酪氨酸蛋白激酶(TPK)的调节作用。以本实验室从植物中提取纯化的二萜类活性物质(RFP134)为诱导分化剂,观察了RFP134对UMR106细胞EGF受体TPK的活性和磷酸化作用的影响,并与RA和RFP134+RA处理细胞做了比较,结果显示EGF与其受体结合后能激活TPK,使TPK活性增加2倍.RFP134,RA,RFP134+RA处理细胞后,分别降低EGF诱导的受体TPK活性50%,43%,55%,降低磷酸化TPK含量55%,36%,53%。从结果中发现无EGF刺激的细胞也具有受体TPK磷酸化作用,用RFP134,RA,RFP134+RA处理细胞,分别降低受体磷酸化TPK含量59%,40%,57%,而且我们发现用EGF诱导的细胞受体TPK含量高于无EGF作用的细胞.提示UMR106细胞本身可能具有受体TPK活性,能够引起细胞受体自动磷酸化,EGF刺激后TPK的磷酸化作用增强,可见RFP134对EGF诱导的TPK磷酸化和无EGF诱导的受体自动磷酸化都具有明显的抑制作用,(并强于RA)这可能与在第二信使水平上阻抑PTPK活性密切相关  相似文献   

2.
RFP134对UMR106细胞EGF受体酪氨酸蛋白激酶的调节作用   总被引:1,自引:0,他引:1  
以大鼠成骨肉瘤细胞(UMR106)为模型,研究了表皮生长因子(EGF)对其受体酪氨酸蛋白激酶(TPK)的调节作用。以及实验室从植物中提取纯化的二萜类活性物质(RFP134)为诱导分化剂,观察了RFP134对UMP106细胞EGF受体TPK的活性和磷酸化作用的影响。并与RA和RFP134+RA处理细胞做了比较。结果显示EGF与其受体结合后能激活TPK,使TPK活性增加2倍。RFP134,RA,RFP  相似文献   

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RRM RNA 结合蛋白在基因的转录后调控中起着重要作用.人GRY-RBP 是我们实验室最近克隆的一个新的全长cDNA,编码一个RRM RNA 结合蛋白.GRY-RBP 的全编码区用PCR扩增后,克隆到pET30a+ 表达载体中,在E.coli中获得了高效表达,表达的GRY-RBP重组蛋白占细菌总蛋白的21% .利用融合在GRY-RBPN 端的His.Tag,采取亲和层析的方法纯化了表达的重组蛋白.为了检测GRY-RBP的RNA 结合活性及其所结合的RNA 性质,将表达的蛋白与poly(A)-Sepharose 4B结合,发现GRY-RBP能与polyA (A)结合,结合活性能被可溶性的poly(A)、poly(C)减弱.改变NaCl浓度和加入不同浓度的酵母tRNA竞争物后,poly(A)结合活性不变.  相似文献   

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首次对犬瘟热病毒(CDV)大熊猫(GP)毒株附着或血凝蛋白(H)基因进行了序列测定并与疫苗株Onderstepoort进行了比较。我们设计合成了4对引物,对GP株进行了RT-PCR扩增与测序。H蛋白基因全长为1946bp,开放阅读框架(ORF)始于21-23位的ATG,终止于1842-1844位的TGA,编码607个氨基酸,该基因序列已被GenBank。将GP毒株与GenBank中疫苗弱毒株Ond  相似文献   

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为表达、获取日本血吸早谷胱甘肽转移酶(SjGST)基因工程重组蛋白,以日本血吸虫(中国大陆株)cDNA为模板,设计、合成特定寡核苷酸引物,RT-PCR法扩增GST编码基因序列,将扩增产物连接pGEM-T克隆载体,再亚克隆到真、原核表达质粒pBK-CMV中,转染大肠杆菌XL1-blue,经IPTG诱导后用SDS-PAGE分析表达效果。结果 RT-PCR法特异性扩增出日本血吸虫GST编码区基因片段,其  相似文献   

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简并PCR法用于白色念珠菌MAPK新基因的筛选   总被引:3,自引:0,他引:3  
MAPK很可能在白色念朱菌形态发生中起作用。根据所有MAPK保守区域VIB和IX的氨基酸序列合成了两个简并的引物,以SC5314染色体DNA作为模板,在非严谨条件下(37℃)进行PCR以筛选白色念球菌中新的MAPK基因,一共测定了100个PCR基因片段的序列,在25个新基因片段中,筛选到两个新的MAPK基因片段,以这两个基因片段为控针从染色体基因库中克隆了对应的全长基因,序列分析表明它们是新的MA  相似文献   

7.
姜勇  王忠 《激光生物学报》1998,7(3):188-191
本文以含外源基因的甲醇酵母表达载体pPIC9/E2F-1-DB质粒DNA电转化甲醇酵母GS115,小规模抽提所得转化子的总DNA,并以其为模板,以乙醇氧化酶(AOX1)5’端序列和3’端的TT序列为引物,进行PCR反应。PCR产物走0.8%Agarose电泳,通过对PCR产物的电泳带型分析,鉴定出甲醇酵母转化子的表型,即Mut^+或Mut^s。这一鉴定结果为转化子的诱导表达产物的SDS-PAGE图  相似文献   

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黄瓜花发育的早期均有雌蕊和雄蕊原基的分化,但在发育过程中,由于雌蕊或雄蕊的发育受到阻滞,导致雄花和雌花的形成。近年来在拟南芥和金鱼草等植物中遗传学的研究表明,花器官的特征是由同源异形基因决定的。在拟南芥中,由于AG在决定雄蕊和雌蕊特征方面起重要作用,本研究利用 RT-PCR技术,从黄瓜的雌、雄蕊中分离出 AG的同源基因,并对其在花发育过程中的表达和可能作用进行了分析。首先,根据AG同源基因的保守区域设计5’简并引物5’-GA(A/G)AT(T/C/A)AA(T/C/A)AA(G/A)(A/C)G(G/T/C)ATCGA(C/A)AAC-3’,然后进行3’,RA CE PCR,扩增出约1kb大小的片段,序列分析表明该片段含有非常保守的MADS box。进而,利用5’ RACE PCR得到全长度的cDNA。该cDNA的核苷酸序列与CUM1(黄瓜 MADS box gene1)同源性高达97%。 CUM1在接牵牛中过量表达可引起花萼变为心皮状和花瓣变为雄蕊,说明CUM1为AG的同源基因。基于该基因与CUM1序列上的高度同源,我们认为其为黄瓜的AG同源基因。该基因命名为CMB1,基因银行登记号为AF286649。Souther  相似文献   

9.
黑子南瓜甘油-3-磷酸酰基转移酶基因的克隆及序列分析   总被引:6,自引:3,他引:3  
依据国外报道的南瓜甘油-3-磷酸转酰酶(GPAT)基因的cDNA序列合成相应引物,用RT-PCR技术,成功地分离了黑子南瓜(Cucurbitaficifolia)GPAT基因的cDNA片段,并亚克隆到了pGEM-T载体系统的多克隆位点上,序列分析表明黑子南瓜GPAT基因的cDNA序列及递推的氨基酸序列与南瓜(Cucurbitamoschata)相比分别具有98%和965%的同源性。在1188bp中有22个核苷酸发生变化,导致13个氨基酸的改变  相似文献   

10.
EB病毒(EBV)是一种与地区性伯基特氏淋巴瘤、鼻咽癌、何杰金氏病等多种人体肿瘤有关的疱疹病毒.已往的研究表明,潜伏膜蛋白(LMP)基因是EBV最可能的致瘤基因.为制备LMP基因转基因小鼠,探讨LMP的体内致瘤作用,首先构建了含鼠金属硫蛋白-1(MT-1)基因调控区和LMP基因编码区的pBR322-MT-LMP质粒,并用电击法将该质粒与pKJ1-Neo质粒共转染人胃癌细胞株MGC,对MT-LMP基因在转染细胞中的整合、转录情况及重金属镉和镍对该融合基因的转录调控进行了研究.结果表明:(1)两质粒共转染效率为86.7%;(2)PCR和Southern杂交分析显示,完整的MT-LMP基因已整合入转染的MGC细胞基因组,且在不同的转染细胞克隆中,MT-LMP基因整合的方式及拷贝数不同,拷贝数从1到19不等;(3)RT-PCR和Northern杂交分析证实,MT-LMP基因不仅在转染的MGC中能够转录,而且在10μmol/L镉诱导下,MT-LMP基因转录增强,平均增高约1.4倍.结果说明,在MT-1基因调控区指导下,LMP基因不但有mRNA水平的表达,而且其表达受重金属镉的调控,上述结果为制备MT-LMP转基因小鼠  相似文献   

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K. Hausmann 《Protoplasma》1979,100(2):199-213
Summary The membranes of the pellicle of the ciliatePseudomicrothorax dubius are investigated using thin section electron microscopy and freeze-fracture replicas. The plasma membrane is covered by a surface coat and is connected to the outer alveolar membrane by short, sometimes branched, bridges. The inner alveolar membrane is coated on both sides. The epiplasm lies in intimate contact with the cytoplasmic surface of this membrane, and there is a corresponding deposit on the other surface. This deposit is regularly striated.The epiplasmic layer and the alveoli are interrupted at sites of cytotic activity,e.g., the attachment sites of trichocysts, the cytoproct, and the parasomal sacs. The striated deposit ends where the epiplasm ends, indicating a direct relationship between these two epimembranous layers.There is a deposit along the sides of the first part of the tip of the trichocysts, and in this region the trichocyst membrane is free of intramembranous particles.The membrane of the parasomal sacs has a coat on both surfaces. That on the extraplasmic surface is similar to the surface coat of the plasma membrane. The origin of the cytoplasmic coat is unknown. The cytotic activity of these sacs is indicated by their highly irregular profiles.  相似文献   

13.
Summary The differentiation of the spermatid, especially in reference to the formation of the flagellum, and transformation of the shape of the nucleus was investigated in the domestic fowl.In the early stage of the spermatid, a prominent Golgi apparatus appears around the centrioles. The Golgi vesicles then surround the axial-filament complex which develops from the distal centriole. These vesicles fuse to form continuous membrane at the earliest stage of flagellar formation, and in the succeeding stage Golgi lamellae are attached to the plasma membrane of the developing flagellum. From these observations, it is assumed that Golgi apparatus may be a source of the membrane system of the flagellum.The microtubules distributed around the nucleus form the circular manchette. The anterior region of the nucleus with the manchette is cylindrical in shape and the posterior region without it remains irregular in shape. When the circular manchette has been completed, the whole nucleus acquires a slender cylindrical shape. The circular manchette then changes into the longitudinal manchette. The nuclei of spermatids without a longitudinal manchette are abnormal in shape. In view of these observations it is assumed that the nuclear shaping of the spermatid may be accomplished by circular manchette and the maintenance of shape of the elongated nucleus by longitudinal manchette.The authors wish to thank Mr. Takayuki Mori for his helpful suggestions and technical advices  相似文献   

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This study aimed to analyze the aqueous humor (AH) and the vitreous body (VB) of the eye of the adult frog Rana temporaria L. as a representative species of amphibians, which lead a semi-terrestrial life. The presence of collagen, albumin, uric acid and electron donors was shown in both media; however, there are slight differences in their concentrations. To determine collagen, a spectral-fluorescent probe, cyanine dye, was used. The presence of collagen in AH of the frog was found at the first time. The total content of electron donors (ascorbic and uric acids, tryptophan, and tyrosine) in VB and HA was roughly estimated at ~ 1.5 × 10− 4 mol/L. Both VB and AH absorb light in similar UV regions. The total protein and albumin contents in AH were found to be somewhat higher than those in VB. The uric acid content was at an equally low level in both intraocular media. It is supposed that the similarity of VB and AH compositions shown in this work is due to some exchange between VB and AH contents in the course of accommodation. The role of intraocular fluids in physiological functions of the eye and in protecting the retina against UV light is discussed.  相似文献   

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Summary The choriocapillaris is a fenestrated capillary bed located posterior to the retinal pigment epithelium. It serves as the main source of supply to the photoreceptors, retinal pigment epithelium, and other cells of the outer retina. The permeability of these capillaries to intravenously injected ferritin (MW — approx. 480,000; mol. diam. 11 nm) was examined in the mouse, rabbit, and guinea pig, each of which is characterized by a different type of retinal vascularization. In all three species, the bulk of the ferritin remained in the capillary lumina, where it appeared to be blocked at the level of the diaphragmed fenestrae. Some ferritin was present in endothelial cell vacuoles. The results confirm previous work on the rat choriocapillaris and indicate that the barrier function of the choriocapillary endothelium is present even among species in which the retinal circulation differs significantly.Supported by NIH grant EY03418  相似文献   

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