Functional characteristics of a novel murine estrogen receptor-beta isoform, estrogen receptor-beta 2.
Functional characteristics of a novel murine estrogen receptor-beta isoform, estrogen receptor-beta 2.
复制标题
新型鼠雌激素受体-β亚型、雌激素受体-β2的功能特征。
DOI：
--
复制
发表时间：
2000
影响因子：
3.5
通讯作者：
L. Murphy
中科院分区：
文献类型：
--
作者：
B. Lu;E. Leygue;Helmut Dotzlaw;L. Murphy;L. Murphy
我们分离出了小鼠雌激素受体-β (ERbeta) 的高表达剪接变体 mRNA，mERbeta2，在野生型 mERbeta1 的外显子 5 和 6 之间包含符合读框的 54 个核苷酸插入。预测的 ERbeta2 蛋白包含插入 mERbeta1 配体结合域的 18 个氨基酸。体外转录/翻译产生的重组蛋白显示，与 mERbeta1 结合的 (3)H-雌二醇 (K(D)=0.56+/- 0.19 nM，平均值+/-s.e.m.，n=3) 相比，mERbeta2 的配体结合显着降低 (K(D)=17.7+/-4.7 nM，平均值+/-s.e.m.，n=3)。两种受体在体外和体内均与回文雌激素反应元件 (ERE) 类似地结合，并且弯曲 DNA 也类似。使用瞬时转染分析对同源鼠细胞系 NIH 3T3 细胞进行转录活性评估。 mERbeta1 与 mERalpha 类似地反式激活 ERE-tk-CAT 报告基因，而 mERbeta2 除在高配体浓度外几乎没有活性。然而，在 mERbeta2 不太可能被配体饱和的条件下，共转染的 mERbeta2 抑制了 mERalpha 和可能的 mERbeta1 对 ERE-tk-CAT 基因的活性。使用“新型雷洛昔芬响应”基因报告系统（TGF-beta3-CAT），我们发现雌二醇和 LY117018 激活该启动子上的 mERalpha 和 mERbeta1 的能力是相同的，并且在雌二醇或 LY117018 存在的情况下，mERbeta2 活性仅略低于使用 mERbeta1 或 mERalpha 观察到的活性。在这些转染条件下，mERbeta1 和 mERbeta2 与 LY117018 配体时都会抑制经典 ERE 调节启动子的转录，这与它们对转化生长因子-β3 启动子的刺激作用形成鲜明对比。这些数据表明，基因表达对相对高表达的鼠类 ERbeta 同种型 mERbeta2 的反应性是配体和启动子特异性的。小鼠组织中 mERbeta1 mRNA 和 mERbeta2 mRNA 表达的相对水平的测定表明，mERbeta2 mRNA 在一些但不是所有组织中占主导地位。这些数据表明 mERbeta2 可能具有一些组织特异性和启动子特异性调节作用。
We have isolated a highly expressed splice variant mRNA of murine estrogen receptor-beta (ERbeta), mERbeta2, containing an in-frame 54 nucleotide insertion between exons 5 and 6 of wild-type mERbeta1. The predicted ERbeta2 protein contains 18 amino acids inserted in the ligand binding domain of mERbeta1. Recombinant protein generated by in vitro transcription/translation showed that mERbeta2 had markedly reduced ligand binding (K(D)=17.7+/-4.7 nM, mean+/-s.e.m., n=3) compared with mERbeta1-bound (3)H-estradiol (K(D)=0.56+/- 0.19 nM, mean+/-s.e.m., n=3). Both receptors bound similarly to palindromic estrogen responsive elements (EREs) in vitro and in vivo, and similarly bent DNA. Transcriptional activity was assessed using transient transfection analysis into a homologous murine cell line, NIH 3T3 cells. mERbeta1 transactivated ERE-tk-CAT reporter genes similarly to mERalpha, whereas mERbeta2 had little activity except at high ligand concentrations. However, under conditions in which mERbeta2 is unlikely to be ligand saturated, co-transfected mERbeta2 inhibited activity of mERalpha and possibly mERbeta1 on ERE-tk-CAT genes. Using a 'novel raloxifene responsive' gene reporter system (TGF-beta3-CAT), we found the ability of estradiol and LY117018 to activate both mERalpha and mERbeta1 on this promoter was identical, and mERbeta2 activity in the presence of either estradiol or LY117018 was only slightly less than that observed with either mERbeta1 or mERalpha. Both mERbeta1 and mERbeta2 when liganded with LY117018 inhibited transcription at a classical ERE-regulated promoter under these transfection conditions, which was in marked contrast to their stimulatory effect at the transforming growth factor-beta3 promoter. These data suggest that responsiveness of gene expression to a relatively highly expressed variant murine ERbeta isoform, mERbeta2, is both ligand and promoter specific. Determination of the relative level of expression of mERbeta1 mRNA and mERbeta2 mRNA in mouse tissues indicated predominance of mERbeta2 mRNA in some but not all tissues. These data suggest that the mERbeta2 may have some tissue-specific and promoter-specific modulatory effects.
细胞介导雌激素反应的能力的限制。
DOI：
10.1210/mend.6.2.1569962
发表时间：
1992
期刊：
Molecular endocrinology (Baltimore, Md.)
影响因子：
--
作者：
Webb,P;Lopez,GN;Greene,GL;Baxter,JD;Kushner,PJ
通讯作者：
Kushner,PJ
新型雌激素受体-β亚型的功能分析。
DOI：
10.1210/mend.13.1.0234
发表时间：
1999
期刊：
Molecular endocrinology (Baltimore, Md.)
影响因子：
--
作者：
Hanstein,B;Liu,H;Yancisin,MC;Brown,M
通讯作者：
Brown,M