Characterization of covalently cross-linked somatostatin receptors in hamster beta cell insulinoma.
Characterization of covalently cross-linked somatostatin receptors in hamster beta cell insulinoma.
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仓鼠β细胞胰岛素瘤中共价交联生长抑素受体的表征。
DOI：
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发表时间：
1988
期刊：
影响因子：
--
通讯作者：
G. Rosselin
中科院分区：
文献类型：
--
作者：
P. Cotroneo;J. Marie;G. Rosselin
用高效液相纯化的125I-[Leu8，D-Trp22，Tyr25]SS-28或125I-SS-28研究了生长抑素-28(SS-28)与仓鼠胰岛素瘤β细胞的选择性结合。观察到单一的高亲和力位点(Kd=53+/-5 Pm)，结合容量为2.85pmol/mg膜蛋白。还发现了大量相对低亲和力的位点。不同多肽抑制~(125)I-SS-28结合的效价顺序为SS-28>SS-14>SMS-201-995，半最大抑制剂量分别为0.16 nM、10 nM和1000 nM。CCK8和其他活性胰多肽(胰升糖素、胰岛素、胃抑制肽、血管活性肠肽、氧合酶调节蛋白)不抑制SS-28受体的结合。125I-SS-28标记的β膜可单独使用可切割的交联剂二硫代丁二胺丙酸酯(1 MM)或与异双功能试剂N-羟基琥珀酰亚胺-4-叠氮苯甲酸酯(HSAB)进行交联。两种膜蛋白经聚丙烯酰胺凝胶电泳法和放射自显影后均有5种分子组成，其分子量分别为196 kDa、132 kDa、69 kDa、45 kDa和28 kDa。196 kDa、132 kDa和45 kDa物种的标记具有特异性，因为它们可以被未标记的SS-28抑制。主要标记物种对应于132 kDa的区带，加入二硫苏糖醇后，这种HSAB共价结合的SS-28受体的迁移率没有变化，表明这种特异的受体不含链间二硫键。SS-28受体的分子质量与豚鼠胰腺腺泡膜的分子质量明显不同，在比较实验中，单个93 kDa的蛋白被鉴定为125I-SS-28受体位点。结合动力学和结构差异均支持SS-28在内分泌胰腺中的选择性作用。
The selective binding of somatostatin-28 (SS-28) to beta cells of hamster insulinoma was characterized using HPLC-purified 125I-[Leu8,D-Trp22,Tyr25]SS-28 or 125I-SS-28. A single class of high-affinity sites (Kd = 53 +/- 5 pM) was observed with a binding capacity of 2.85 pmol/mg membrane protein. A large number of relatively low-affinity sites was found also. The order of potency of different peptides to inhibit 125I-SS-28 binding is SS-28 greater than SS-14 greater than SMS-201-995 and the respective half-maximal inhibitory doses are 0.16 nM, 10 nM and 1000 nM. CCK8 and other active pancreatic peptides (glucagon, insulin, gastric inhibitory peptide, vasoactive intestinal peptide, oxyntomodulin) do not inhibit the SS-28 receptor binding. 125I-SS-28-labeled beta membranes were successfully cross-linked using either the cleavable cross-linker dithiobis(succinimidylpropionate) (1 mM) alone or with a heterobifunctional agent, N-hydroxysuccinimidyl-4-azidobenzoate (HSAB). In both cases five molecular components were revealed, after polyacrylamide gel electrophoresis of the membrane proteins and autoradiography, with the following molecular mass: 196-kDa, 132 kDa, 69 kDa, 45 kDa and 28 kDa. The labeling of 196-kDa, 132-kDa and 45-kDa species was specific in that they could be inhibited by unlabeled SS-28. The major labeled species corresponds to the 132-kDa band and no change in the mobility of this HSAB covalently bound SS-28 receptor was found after addition of dithiothreitol, suggesting that this specific receptor does not contain interchain disulphide bonds. The molecular mass of SS-28 receptors differs markedly from that of guinea-pig pancreatic acinar membranes, where a single 93-kDa protein is identified as a 125I-SS-28 receptor site in comparative experiments. Both the binding kinetics and structural differences sustain the selective action of SS-28 in the endocrine pancreas.
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DOI：
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发表时间：
1986
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Susini,C;Bailey,A;Szecowka,J;Williams,JA
通讯作者：
Williams,JA
胰腺 β 细胞上生长抑素 28 的特异性高亲和力结合位点：与脑生长抑素受体的差异。
影响因子：
4.8
作者：
Reubi,JC;Rivier,J;Perrin,M;Brown,M;Vale,W
通讯作者：
Vale,W
通过亲和标记鉴定交感神经节膜中的神经生长因子受体蛋白。
DOI：
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发表时间：
1981
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Massague,J;Guillette,BJ;Czech,MP;Morgan,CJ;Bradshaw,RA
通讯作者：
Bradshaw,RA
分离的胰腺腺泡细胞质膜上的生长抑素受体。
DOI：
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发表时间：
1984
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Sakamoto,C;Goldfine,ID;Williams,JA
通讯作者：
Williams,JA