首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 78 毫秒
1.
大鼠脊髓细胞膜胰岛素受体的结合特性   总被引:3,自引:0,他引:3  
大鼠脊髓细胞膜胰岛素受体的结合特性朱尚权,徐明华,张新堂,叶莺(中国科学院上海生物化学研究所,200031)姜新建,林淑琼(上海市第一人民医院康复科,200085)关键词胰岛素受体,脊髓细胞膜免疫组织化学、放射免疫自显影和放射受体测定技术已证明脑各区...  相似文献   

2.
“胰岛素-类胰岛素生长因子-Ⅰ片段”杂交分子的促生长活性研究张新,唐月华,冯佑民,景乃禾(中国科学院上海生物化学研究所,中国科学院上海生物化学研究所分子生物学国家重点实验室,200031)关键词胰岛素,类胰岛素生长因子-Ⅰ,杂交分子,促生长活性胰岛素...  相似文献   

3.
不同种属动物血清转铁蛋白促癌细胞生长作用的比较史民景乃禾1冯佑民(中国科学院上海生物化学研究所分子生物学国家重点实验室,上海200031;1中国科学院上海生物化学研究所,上海200031)关键词血清转铁蛋白;细胞增殖;小鼠乳腺癌细胞转铁蛋白(tran...  相似文献   

4.
G蛋白偶联受体介导的神经信号跨膜转导郭君,周安武,杜雨苍(中国科学院上海生物化学研究所,上海200031)关键词G蛋白偶联受体,神经信号跨膜转导受体是细胞膜或细胞内的一些首先能与生物活性物质相互作用的分子,它们能够识别配基并与其结合,然后将受体与配基...  相似文献   

5.
具靶向性的转铁蛋白—脂质体的制备   总被引:2,自引:0,他引:2  
具靶向性的转铁蛋白──脂质体的制备杨静平,王瓞,林其谁(中国科学院上海生物化学研究所分子生物学国家重点实验室,200031)关键词脂质体;人转铁蛋白;靶向性;癌细胞;天花粉蛋白利用正常细胞和癌细胞表面受体或抗原物质的差异,用相应配体修饰脂质体表面,使...  相似文献   

6.
 溪七鳃鳗肌肉细胞膜胰岛素受体的研究张新堂,徐明华,王楠,朱尚权(中国科学院上海生物化学研究所,上海200031)郭春生(哈尔滨师范大学生化学研究所,哈尔滨150080)七鳃鳗是现存的最原始的圆口类无颌脊推动物之一,它的形态学和生理学特性已有详细研究和...  相似文献   

7.
细胞因子受体及其介导的信号转导   总被引:1,自引:0,他引:1  
细胞因子受体及其介导的信号转导朱锦芳,郑仲承,刘新垣(中国科学院上海生物化学研究所,上海200031)关键词细胞因子,受体,信号转导,Ras-MAPK途径,JAK-STAT途径免疫或造血细胞之间的相互通讯依靠一种可溶性的细胞因子介导。细胞因子包括白细...  相似文献   

8.
用计算机构建白细胞介素一2与其受体相互作用的空间模型王志勇,王翼飞,郑仲承,刘新垣(中国科学院上海生物化学研究所,200031)关键词白细胞介素-2;白细胞介素-2受体;结合位点;空间相互作用1987年Brandhuber等在报道3.A分辨率的白细胞...  相似文献   

9.
AVP4┐8的鼠脑结合位点有别于VP受体阎庆武杜雨苍*(中国科学院上海生物化学研究所,上海200031)加压素(VP)是一种下丘脑垂体后叶激素。它由9个氨基酸残基组成并且种属差异很小。大多数哺乳类VP的组成都是Cys1-Tyr2-Phe3-Gln4-...  相似文献   

10.
1980年6月27日至28日,由上海市食品工业公司、中国科学院上海生物化学研究所联合组织与主持,在上海酒精二厂召开了《纤维素酶制剂生产技术鉴定会》。会议对上海酒精二厂、中国科学院上海生物化学研究所东风生化试剂厂采用上海化学纤维六厂、上海酒精二厂、  相似文献   

11.
12.
In this study, we developed a human prostatic epithelial cell line BPH-1-AR stably expressing AR by lentiviral transduction. Characterization by immunoblot and RT-PCR showed that AR was stably expressed in all representative BPH-1-AR clones. Androgen treatment induced a secretory differentiation phenotype in BPH-1-AR cells but suppressed their cell proliferation. Treatments with AR agonists induced transactivation of a transfected PSA-gene promoter reporter in BPH-1-AR cells, whereas this transactivation was suppressed by an AR antagonist flutamide, indicating that the transduced AR in BPH-1-AR cells was functional. Finally, we utilized BPH-1-AR cells to evaluate the androgenic activities and growth effects of five newly developed non-steroidal compounds. Results showed that these compounds showed androgenic activities and growth-inhibitory effects on BPH-1-AR cells. Our results showed that BPH-1-AR cell line would be a valuable in vitro model for the study of androgen-regulated processes in prostatic epithelial cells and identification of compounds with AR-modulating activities.  相似文献   

13.
14.
The HT29 cell line, derived from a human colon adenocarcinoma, is able to differentiate if galactose replaces glucose in the culture medium. We have isolated a clone (HT29-18) from this cell line which displays differentiated properties of the parent cell line. HT29-18 cells grown in glucose-containing medium form multiple layers of round cells without specific cell-cell adhesion. In contrast, when grown in galactose-containing medium, they form a monolayer with tight junctions and exhibit a well differentiated brush border at their apical membrane, which faces the culture medium. The polarized properties of HT29-18 cells grown in galactose-containing medium were demonstrated by immunofluorescent techniques with antibodies against 2 plasma membrane proteins. Class I histocompatibility antigens (HLA) and transferrin receptors, 2 well characterized integral membrane proteins, are uniformly distributed on the cell surface of undifferentiated HT29-18 cells, but acquire a polarized distribution during differentiation, localized on the basolateral membranes and absent from the apical surface. Binding of 125I-labeled transferrin was used to determine transferrin receptor distribution on apical and basolateral membranes. Functional tight junctions in the differentiated cultures were demonstrated, as the monolayer was impermeable to a permeation dye (ruthenium red) as well as to antibodies. The sealing of these tight junctions is, as in vivo, Ca++-dependent as they could be opened by a short incubation in Ca++-free medium.  相似文献   

15.
We present a new cell line, EJ established from an invasive endometrioid adenocarcinoma of the uterine corpus in a 56-year-old patient. The cells show rapid growth in culture with a doubling time of 16 h and high migration activity. Monolayer-cultured cells were polygonal in shape showing a tendency to pile up without contact inhibition. Subcutaneous transplantation of the EJ cells into nude mice formed solid tumors that were histologically diagnosed as adenocarcinoma, whereas no metastasis was observed. Cultured EJ cells produced tissue polypeptide antigen (IPA). Genetic and molecular analyses revealed high telomerase activity but not estrogen receptor alpha expression. Using the DNA sequencing technique, we have screened EJ cells for p53 mutation in exon 5 to 8 but no mutation of p53 was observed. This cell line appears to represent the development of a more malignant clone with divergent receptor function and growth behavior, and provides us with an interesting new tool for the study of tumorigenesis in the human endometrium.  相似文献   

16.
Abstract Natural partial structures of lipopolysaccharide (LPS) as well as synthetic analogues and derivatives of lipid A were compared with respect to inhibit the binding of 125I-labelled Re-chemotype LPS to mouse macrophage-like J774.1 cells to induce cytokine-release in J774.1 cells. LPS, synthetic Escherichia coli -type lipid A (compound 506) and tetraacyl percursor Ia (compound 406) inhibited the binding of 125I-LPS to macrophage-like J774.1 cells and induced the release of tumor ncerosis factor α (TNFα) and interleukin 6 (IL-6). Deacylated R-chemotype LPS preparations were completely inactive in inhibiting binding and in inducing cytokine-release. Among tetraacyl compounds, the inhibition-capacity of LPS-binding was in decreasing order: PE-4 ( α -phosphonooxyethyl analogue of 406)>406⪢>404(4′-monophosphoryl partial structure of 406)>405 (1-monophosphoryl partial structure of 406). In the case of hexaccyl preparations, compounds 506, PE-1 (α-phosphonooxyethyl analogue of 506) and PE-2 (differing from PE-1 in having 14:0 at positions 2 and 3 of the reducing GlcN) inhibited LPS-binding and induced cytokine release equally well, whereas preparation PE-3 (differing from PE-2 in containing a β-phosphhonooxyethyl group) showed a substantially lower capacity in binding-inhibition and cytokine-induction. The conclusion is that chemical changes in the hydrophilic lipid A backbone reduce the capacity of lipid A to bind to cells, whereas the number of fatty acids determines the capacity of lipid A to activate cells. These results indicate that the bisphosphorylated hexosamine backbone of lipid A is essential for specific binding of LPS to macrophages and that the acylation pattern plays a critical role for LPS-promoted cell activation, i.e. cytokine induction.  相似文献   

17.
To address conflicting reports concerning the number of angiotensin II (AII) receptor type 1 (AT1) coding loci in vertebrates, Southern blot analysis was used to determine the genomic representation of AT1 receptor genes in animals comprising a divergent evolutionary spectrum. The data demonstrate that the AT1 receptor gene is present as a single genomic copy in a broad spectrum of animals including human, monkey, dog, cow, rabbit, and chicken. In contrast, members of the rodent taxonomic order contain two genes in their genomes. These two genes may have arisen in rodents as a consequence of a gene duplication event that occurred during evolution following the branching of rodents from the mammalian phylogenetic tree. In order to investigate the properties of the human AT1 receptor in a pure cell system, the recombinant human AT1 receptor was stably expressed in mouse L cells. An isolated cell line, designated LhAT1-D6, was found to express abundant levels of recombinant receptor [430±15 fmol/mg] exhibiting high affinity [KD=0.15±0.02 nM] for [125I][SAR1, IIe8] angiotensin II (SIA). The pharmacological profile of ligands competing for [125I] SIA binding to the expressed recèptor was in accordance with that of the natural receptor. Radioligand binding of the expressed receptor was decreased in the presence of the non-hydrolyzable analog of GTP, guanosine 5-(-thio) triphosphate [GTPS]. Angiotensin II evoked a rapid efflux of45Ca2+ from LhAT1-D6 cells that was blocked by AT1 receptor specific antagonists. In addition, AII inhibited forskolin-stimulated cAMP accumulation in these cells which was blocked by the AT-1 antagonist. Thus, the LhAT1-D6 cell line provides a powerful tool to explore the human AT1 receptor regulation.  相似文献   

18.
本文以[~3H]Dex为配体,采用完整细胞GCR和核特异结合百分率的测定方法检测了人体肝癌细胞系(SMMC-7721)的GCR。实验表明,该细胞具有高亲和力、低容量、能与GC进行特异结合的Dex结合部位,该结合部位与[~3H]Dex结合后可向核内转位,因而具备了作为GCR的基本条件。但该细胞的GCR与正常细胞的GCR相比较亦有些差别,GC与受体结合后不能诱导TAT的生成。本文对上述改变的可能机理进行了讨论。  相似文献   

19.
Cultured NCB-20 hybrid cells express adenylate cyclase-coupled receptors for 5-hydroxytryptamine (5-HT) that correspond biochemically and pharmacologically to 5-HT1 receptors in rodent brain membrane preparations, apart from a much-reduced affinity for 5-HT (160 nM compared to less than 5 nM in brain). Since NCB-20 cells also differ from rodent brain both qualitatively and quantitatively in their ganglioside composition, the effects of exogenously added gangliosides on the affinity of the 5-HT1 receptor for 5-HT were tested. Both GM1 ganglioside (the cholera toxin receptor) and tetrasialoganglioside GQ1b produced a 10-fold increase in receptor affinity for [3H]5-HT, measured by binding studies. All gangliosides, at submicromolar concentrations, resulted in significantly reduced EC50 values for 5-HT-mediated elevation of intracellular cyclic AMP levels. GQ1b had the capacity to most dramatically enhance the potency of 5-HT in mediating increases in cyclic AMP levels. Gangliosides had no effect on the potency of DADLE or 3,4-dihydroxyphenylethylamine (dopamine)-mediated depression of cyclic AMP levels, suggesting some specificity for 5-HT. Our data are interpreted as implying a specific role for polysialogangliosides in modulating the affinity of the 5-HT1 receptor and the coupling of the 5-HT1 receptor-guanine nucleotide binding protein adenylate cyclase complex.  相似文献   

20.
为研究清道夫受体与细胞内酷不氨酸蛋白激酶的关系,用酪氨酸蛋白激酶抑制剂genistein处理人U937细胞。分别测定对照组和处理组细胞对碘标记的氧化低密度脂蛋白[^125I]ox-LDL的结合、降解以及细胞内脂质蓄积的程度;并利用放射自显影的方法观察药物对细胞表面受体数目的影响,利用RT-PCR法进一步探讨药物作用的分子机制。结果发现genistein可以抑制细胞表达结合[^125I]ox-LDL,抑制细胞表面受全的表达以及细胞内降解[^125I]ox-LDL,抑制细胞内胆固醇脂的蓄积,并且抑制SR-A mRNA的转录,提示清道夫受体的活性可能与细胞内蛋白质酪氨酸磷酸化水平密切相关,genistein所引起的酪氨酸磷酸化水平下降可影响SR-A基因转录和翻译。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号