Mapping the HSP90 binding region of the glucocorticoid receptor.
Mapping the HSP90 binding region of the glucocorticoid receptor.
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DOI：
10.1016/s0021-9258(19)38489-3
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发表时间：
1990-07
期刊：
影响因子：
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通讯作者：
K. J. Howard;S. Holley;K. Yamamoto;C. Distelhorst
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文献类型：
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作者：
K. J. Howard;S. Holley;K. Yamamoto;C. Distelhorst
在动物细胞中，未配体的类固醇受体与90 kDa的热休克蛋白HSP 90复合;受体与激素结合导致HSP 90的释放。我们发现，795个氨基酸的大鼠糖皮质激素受体蛋白形成寡聚体复合物在体外合成后，在兔网织红细胞裂解物，这些寡聚体也解离激素的存在下。当X795（一种仅含有蛋白质C-末端一半（氨基酸407-795）的受体衍生物）在体外翻译时，形成了类似的复合物。此外，X795从网织红细胞裂解物中与HSP 90一起被三种不同的抗HSP 90单克隆抗体共免疫吸附，表明体外翻译的受体结合HSP 90，并且相互作用发生在受体的C-末端一半内。为了更详细地定位HSP 90结合区，在体外翻译X795的各种缺失突变体，并测定寡聚体形成和与HSP 90的共免疫吸附。结果表明，热休克蛋白90与受体的激素结合域的一个亚区，氨基酸568和616之间的相互作用。这些发现与HSP 90可能参与类固醇受体信号转导机制的观点一致。
In animal cells, unliganded steroid receptors are complexed with a 90-kDa heat shock protein, HSP90; hormone binding by the receptor leads to the release of HSP90. We found that the 795-amino acid rat glucocorticoid receptor protein formed oligomeric complexes in vitro upon synthesis in rabbit reticulocyte lysates; these oligomers also dissociated in the presence of hormone. Similar complexes formed when X795, a receptor derivative containing only the C-terminal half (amino acids 407-795) of the protein, was translated in vitro. Moreover, X795 was co-immunoadsorbed from the reticulocyte lysates together with HSP90 by three different anti-HSP90 monoclonal antibodies, indicating that the in vitro translated receptor binds HSP90 and that the interaction occurs within the C-terminal half of the receptor. To localize the HSP90 binding region in greater detail, various deletion mutants of X795 were translated in vitro and assayed for oligomer formation and for co-immunoadsorption with HSP90. The results indicated that HSP90 interacted with the receptor within a subregion of the hormone binding domain, between amino acids 568 and 616. These findings are consistent with the proposal that HSP90 may participate in the mechanism of signal transduction by steroid receptors.