Environmental estrogens induce transcriptionally active estrogen receptor dimers in yeast: activity potentiated by the coactivator RIP140.
Environmental estrogens induce transcriptionally active estrogen receptor dimers in yeast: activity potentiated by the coactivator RIP140.
复制标题
环境雌激素诱导酵母中的转录活性雌激素受体二聚体：共激活因子RIP140增强的活性。
DOI：
10.1289/ehp.0010897
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发表时间：
2000-02
影响因子：
10.4
通讯作者：
Khan SA
中科院分区：
文献类型：
--
作者：
Sheeler CQ;Dudley MW;Khan SA
我们使用三种酵母遗传系统研究了辛基酚(OP)、双酚A(BPA)、o，p‘-DDT和o，p’-DDE诱导人雌激素受体(HER)二聚化和转录激活的雌激素样活性。我们已经用酵母双杂交实验证明OP、BPA和o，p‘-DDT可以诱导Her的配体依赖的二聚化。所有三种异种雌激素加上雌二醇，都能增强依赖雌激素反应元件(ERE)的HER转录激活。在受体相互作用蛋白140(RIP140)存在下，雌激素、OP、BPA和o，p‘-DDT的ERE依赖活性显著增加100倍。建立了一种酵母全细胞[(3)H]雌二醇结合试验，以确定HER上的相互作用位置。我们通过在PCY2酵母中与5微米未标记雌二醇的平行孵育来确定非特异性结合。在测试的浓度下，未标记的雌二醇、OP和BPA取代了[(3)H]雌二醇，而所测试的o，p‘-DDT和o，p’-DDE浓度不足以抑制结合。在增加雌二醇和OP(1微米)或BPA(1微米)浓度的情况下培养酵母，既不能阻止也不能改变雌二醇对其活性的影响。我们在所使用的任何酵母模型中都没有观察到o，p‘-DDE的激动活性。这些结果表明，OP、BPA和o，p‘-DDT通过ER发挥其雌激素样活性的方式类似于雌二醇，而共激活剂RIP140显著增强这种活性。
We used three yeast genetic systems to investigate the estrogen-like activity of octylphenol (OP), bisphenol-A (BPA), o,p'-DDT, and o, p'-DDE to induce human estrogen receptor (hER) dimerization and transcriptional activation. We have demonstrated that OP, BPA, and o, p'-DDT can induce hER ligand-dependent dimerization using a yeast two-hybrid assay. All three xenoestrogens, plus estradiol, enhanced estrogen response element (ERE)-dependent transcriptional activation of hER. In the presence of receptor interacting protein 140 (RIP140), ERE-dependent activity was dramatically amplified by 100-fold for estradiol, OP, BPA, and o,p'-DDT. A yeast whole-cell [(3)H]estradiol binding assay was developed to determine the site of interaction on the hER. We determined nonspecific binding by parallel incubations run in the presence of 5 microM unlabelled estradiol in PCY2 yeast. At the concentrations tested, unlabeled estradiol, OP, and BPA displaced [(3)H]estradiol in this binding assay, whereas the concentrations of o,p'-DDT and o,p'-DDE tested were insufficient to inhibit binding. Incubating yeast in the presence of increasing concentrations of estradiol and OP (1 microM) or BPA (1 microM) neither blocked nor altered the effect of estradiol on hER activity. We observed no agonistic activity of o,p'-DDE in any of the yeast models used. These results suggest that OP, BPA, and o,p'-DDT exert their estrogen-like activity through the ER in a manner similar to that of estradiol, and the coactivator RIP140 markedly potentiates this activity.