Insulin-like growth factor receptors in rat placental membranes.
Insulin-like growth factor receptors in rat placental membranes.
复制标题
大鼠胎盘膜中的胰岛素样生长因子受体。
作者：
S. J. Pilistine;A. Moses;H. Munro
通过竞争性结合研究和共价交联，然后进行十二烷基硫酸钠-聚丙烯酰胺凝胶电泳，研究了大鼠胎盘微粒体膜中胰岛素样生长因子（IGF）受体的性质和相对数量。结合研究表明，100 微克膜蛋白特异性结合 26.5% 的[125I]碘-IGF-II、19.6% 的[125I]碘倍增刺激活性 III-2 [(125I]碘-MSA-III-2) 和 11.5% 的[125I]碘-IGF-I。 IGF-II 与 MSA-III-2 等价，并且在与 [125I]碘-IGF-I 竞争结合方面，两者的效力大约是 IGF-I 的两倍。相反，IGF-I 竞争结合[125I]碘-MSA 和[125I]碘-IGF-II，其效力仅为未标记的 MSA 和 IGF-II 的 5-20%。胰岛素与 [125I] 碘-IGF-I 竞争结合较弱（在 20 微克/ml 下实现半最大位移），但不与 [125I] 碘-MSA 竞争结合。该证据表明，虽然 IGF-I 与 IGF-I 和 IGF-II 受体结合，但大部分 IGF-I 结合是由于与 IGF-II 受体的相互作用。使用[125I]碘-IGF-I与胎盘膜受体共价交联，然后进行十二烷基硫酸钠-聚丙烯酰胺凝胶电泳的研究证实，IGF-I受体亚基的分子种类特征存在于大鼠胎盘中。结论是，大鼠胎盘与人类胎盘一样，含有两种类型 IGF 的受体。与人类胎盘不同，大多数受体属于 IGF-II 类型。
The nature and relative quantity of insulin-like growth factor (IGF) receptors in rat placental microsomal membranes was investigated by competitive binding studies and covalent cross-linking followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Binding studies revealed that 100 micrograms membrane protein specifically bound 26.5% of [125I]iodo-IGF-II, 19.6% of [125I]iodomultiplication-stimulating activity III-2 [( 125I]iodo-MSA-III-2), and 11.5% [125I]iodo-IGF-I. IGF-II was equipotent with MSA-III-2, and both were approximately twice as potent as IGF-I in competing with [125I]iodo-IGF-I for binding. In contrast, IGF-I competed for the binding of [125I]iodo-MSA and [125I]iodo-IGF-II with only 5-20% the potency of unlabeled MSA and IGF-II. Insulin competed weakly with [125I] iodo-IGF-I for binding (achieving half-maximal displacement at 20 micrograms/ml), but did not compete with [125I]iodo-MSA for binding. This evidence suggested that while IGF-I binds to both IGF-I and IGF-II receptors, the majority of IGF-I binding is due to an interaction with IGF-II receptors. Studies using [125I]iodo-IGF-I covalently cross-linked to placental membrane receptors followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis confirmed that molecular species characteristic of the subunits of IGF-I receptors are present in rat placenta. It is concluded that rat placenta, like human placenta, contains receptors for both types of IGFs. Unlike human placenta, the majority of the receptors are of the IGF-II type.
大鼠和人体组织膜中增殖刺激活性受体的亲和标记。
DOI：
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发表时间：
1981
期刊：
The Journal of biological chemistry
影响因子：
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作者：
Massague,J;Guillette,BJ;Czech,MP
通讯作者：
Czech,MP