Characterization of insulin-like growth factor-I receptors in PC12 pheochromocytoma cells and bovine adrenal medulla.
Characterization of insulin-like growth factor-I receptors in PC12 pheochromocytoma cells and bovine adrenal medulla.
复制标题
PC12 嗜铬细胞瘤细胞和牛肾上腺髓质中胰岛素样生长因子-I 受体的表征。
DOI：
10.1111/j.1471-4159.1989.tb07392.x
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发表时间：
1989
影响因子：
4.7
通讯作者：
Perlman,RL
中科院分区：
文献类型：
--
作者：
Dahmer,MK;Ji,L;Perlman,RL
竞争性结合研究表明，PC 12细胞具有胰岛素样生长因子-I（IGF-I）受体。每个细胞有约11，100 ± 1，500个IGF-I受体;这些受体对IGF-I的表观KD为7.2 ± 0.6 nM。125 I-IGF-I与PC 12细胞的共价交联标记了125，000 - 130，000-Mr蛋白，推测为IGF-I受体的α亚基。虽然PC 12细胞也有胰岛素受体，但125 I-IGF-I似乎与IGF-I受体交联，因为100 nMIGF-I竞争标记，而100 nMinsulin没有。牛嗜铬细胞也有IGF-I受体。通过麦胚凝集素-琼脂糖色谱法纯化受体后，检测了来自牛肾上腺髓质和PC 12细胞的IGF-I受体的蛋白质酪氨酰激酶活性。IGF-I（10 nM）刺激两种制剂中IGF-I受体β亚基的自磷酸化;两种来源的β亚基的Mr值均为1097，000。IGF-I还通过两种受体制剂刺激合成底物poly（Glu：Tyr）4：1的磷酸化。IGF-I（IC 50为0.2 nM）在刺激牛肾上腺髓质制剂对聚（谷氨酸：酪氨酸）的磷酸化方面比胰岛素强得多。最大浓度的IGF-I（10 nM）使磷酸化增加约3倍。在PC 12细胞受体制剂刺激聚（Glu：Tyr）磷酸化方面，IGF-I比胰岛素稍有效，但在浓度高达100 nM时，两种配体均未产生最大效应。这一结果可能反映了PCI 2细胞上IGF-I和胰岛素受体数量相当。我们的数据表明，PC 12细胞上的IGF-I受体与肾上腺髓质和其他组织中的IGF-I受体相似。据推测，这些受体负责IGF-I刺激PC 12细胞复制。
Competitive binding studies indicated that PC 12 cells have receptors for insulin‐like growth factor‐I (IGF‐I). There are ∼ 11,100 ± 1,500 IGF‐I receptors/cell; these receptors have an apparentKDfor IGF‐I of 7.2 ± 0.6 nM.Covalent cross‐linking ofl25I‐IGF‐I to PC 12 cells labeled a 125,000‐130,000‐Mrprotein, presumably the α‐subunit of the IGF‐I receptor. Although PC 12 cells also have insulin receptors, the125I‐IGF‐I appeared to be cross‐linked to IGF‐I receptors, because 100 nMIGF‐I competed for labeling but 100 nMinsulin did not. Bovine chromaffin cells also have IGF‐I receptors. The protein tyrosyl kinase activity of IGF‐I receptors from bovine adrenal medulla and PC 12 cells was examined after purification of the receptors by wheat germ agglutinin‐Sepharose chromatography. IGF‐I (10 nM) stimulated autophosphorylation of the β‐subunits of the IGF‐I receptors from both preparations; the β‐subunits from both sources had Mrvalues of ∼97,000. IGF‐I also stimulated phosphorylation of the synthetic substrate poly(Glu:Tyr)4:1 by both receptor preparations. IGF‐I (IC50of ∼0.2 nM) was much more potent than insulin at stimulating phosphorylation of poly(Glu:Tyr) by the bovine adrenal medulla preparation. A maximal concentration of IGF‐I (10 nM) increased phosphorylation approximately threefold. IGF‐I was slightly more effective than insulin at stimulating the phosphorylation of poly(Glu:Tyr) by the PC 12 cell receptor preparation, but neither ligand produced a maximal effect at concentrations up to 100 nM.This result probably reflects the presence of comparable numbers of IGF‐I and insulin receptors on PCI 2 cells. Our data indicate that the IGF‐I receptors on PC 12 cells are similar to IGF‐I receptors in the adrenal medulla and other tissues. Presumably these receptors are responsible for the stimulation of PC 12 cell replication by IGF‐I.