Rescue of hypogonadotropic hypogonadism-causing and manufactured GnRH receptor mutants by a specific protein-folding template: Misrouted proteins as a novel disease etiology and therapeutic target
Rescue of hypogonadotropic hypogonadism-causing and manufactured GnRH receptor mutants by a specific protein-folding template: Misrouted proteins as a novel disease etiology and therapeutic target
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DOI：
10.1210/jc.87.7.3255
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发表时间：
2002-07-01
影响因子：
5.8
通讯作者：
Conn, PM
中科院分区：
文献类型：
--
作者：
Janovick, JA;Maya-Nunez, G;Conn, PM
在本研究中，我们证明了药物救援（通过配体结合和受体与效应物偶联的恢复评估）从低促性腺激素性性腺功能减退症患者中鉴定的5种天然存在的GnRH受体（GnRHR）突变体（（TI）-I-32、（EK）-K-90、（CY）-Y-200、（CY）-Y-279和（LR）-R-266），以及拯救在预期参与三级受体结构的建立的位点处有意制造的具有内部或末端缺失或取代的其它缺陷受体。所用的药理学试剂是一种小的膜渗透分子，最初设计为口服活性的非肽受体拮抗剂，但据信其功能为折叠模板，能够纠正突变引起的结构缺陷，从而恢复功能。在抢救后，可以明显地去除该药剂。被拯救的受体现在稳定在质膜上，将配体结合偶联到适当的效应系统的激活上。作为比较，GnRHR的低、中或高亲和力肽拮抗剂（不穿透细胞）不能有效挽救，因为它是非。结合拯救剂的拟肽同类物;后一种作用证明了拯救剂的特异性。我们的研究结果，采取与早期的研究显示救援的突变体的受体结构，增强质膜表达的GnRHR的修改，表明突变体GnRHR往往没有失去内在的功能，并受到救援的技术，增强膜表达。目前的研究结果证明了基于药物拯救的方法的有效性，并提出了干预这种疾病和类似疾病的新方法的基础。
In the present study, we demonstrate pharmacological rescue (assessed by ligand binding and restoration of receptor coupling to effector) of five naturally occurring GnRH receptor (GnRHR) mutants ((TI)-I-32, (EK)-K-90, (CY)-Y-200, (CY)-Y-279, and (LR)-R-266), identified from patients with hypogonadotropic hypogonadism, as well as rescue of other defective receptors intentionally manufactured with internal or terminal deletions or substitutions at sites expected to be involved in establishment of tertiary receptor structure. The pharmacological agent used is a small, membrane-permeant molecule, originally designed as an orally active, nonpeptide receptor antagonist, but is believed to function as a folding template, capable of correcting the structural defects caused by the mutations and thereby restoring function. After rescue, this agent can be demonstrably removed. The rescued receptor, now stabilized in the plasma membrane, couples ligand binding to activation of the appropriate effector system. For comparison, low-, intermediate-, or high-affinity peptide antagonists of GnRHR (that do not penetrate the cell) were unable to effect rescue, as was a non. binding peptidomimetic congener of the rescue agent; this latter effect demonstrates specificity of the rescue agent. Our findings, taken in concert with an earlier study showing rescue of a mutant by modifications to the receptor structure that enhance plasma membrane expression of the GnRHR, suggest that mutant GnRHRs have frequently not lost intrinsic functionality and are subject to rescue by techniques that enhance membrane expression. The present findings demonstrate the efficacy of an approach based on pharmacological rescue and suggest the basis of new approaches for intervention in this and similar diseases.