Impaired nuclear translocation, nuclear matrix targeting, and intranuclear mobility of mutant androgen receptors carrying amino acid substitutions in the deoxyribonucleic acid-binding domain derived from androgen insensitivity syndrome patients
Impaired nuclear translocation, nuclear matrix targeting, and intranuclear mobility of mutant androgen receptors carrying amino acid substitutions in the deoxyribonucleic acid-binding domain derived from androgen insensitivity syndrome patients
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DOI：
10.1210/jc.2005-0179
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发表时间：
2005-11-01
影响因子：
5.8
通讯作者：
Takayanagi, R
中科院分区：
文献类型：
--
作者：
Kawate, H;Wu, Y;Takayanagi, R
内容：最近的影像学研究表明，雄激素受体（AR）是配体依赖性地从细胞质易位到细胞核，并形成核内的细灶。在这项研究中，我们检查了在两名雄激素不敏感综合征（AIS）患者中检测到的突变AR的细胞内动力学是否受损。目的：对DNA结合结构域突变的AR进行功能表征，并与野生型AR进行比较。在完全型AIS患者（受试者1）中，AR第一个锌指基序中的半胱氨酸残基579被苯丙氨酸取代（AR-C579 F）。结果：AR-F582 Y的反式激活活性低于野生型AR的10%，而AR-C579 F则没有检测到配体依赖的反式激活。融合到绿色荧光蛋白的受体的图像分析表明，野生型AR是配体依赖性地易位到细胞核中，在那里它形成精细的亚核灶。令人惊讶的是，在加入双氢睾酮后，这两种突变AR最初形成了大的细胞质点，通过电子显微镜发现其中许多点靠近线粒体。随后，与野生型AR相比，一部分配体结合的突变AR逐渐进入细胞核，形成数量较少的较大点。荧光恢复后的光漂白分析显示，突变AR的核内流动性下降，与野生型AR。结论：这些结果表明，异常易位，本地化，和移动的突变AR可能是AIS在这些科目的原因。
Context: Recent imaging studies revealed that androgen receptor (AR) is ligand-dependently translocated from the cytoplasm into the nucleus and forms intranuclear fine foci. In this study, we examined whether intracellular dynamics of mutant ARs detected in two androgen insensitivity syndrome (AIS) patients was impaired.Objective: ARs with mutations in the DNA-binding domain were functionally characterized and compared with the wild-type AR.Patients: In a complete AIS patient ( subject 1), cysteine residue 579 in the first zinc finger motif of AR was substituted for phenylalanine (AR-C579F). Another mutation (AR-F582Y) was found in a partial AIS patient (subject 2).Results: AR-F582Y retained less than 10% of the transactivation activity of the wild-type AR, whereas no ligand-dependent transactivation was detected for AR-C579F. Image analyses of the receptors fused to green fluorescent protein showed that the wild-type AR was ligand-dependently translocated into the nucleus in which it formed fine subnuclear foci. Surprisingly, after the addition of dihydrotestosterone, the two mutant ARs initially formed large cytoplasmic dots, many of which were found to be close to mitochondria by electron microscopy. Subsequently, a part of the ligand-bound mutant ARs gradually entered the nucleus to form a smaller number of larger dots, compared with the wild-type AR. Fluorescence recovery after photobleaching analysis revealed that the intranuclear mobility of the mutant ARs decreased, compared with that of the wild-type AR.Conclusions: These results suggest that the abnormal translocation, localization, and mobility of the mutant ARs may be the cause of AIS in these subjects.