The estrogen receptor in MCF-7 cells: evidence from dense amino acid labeling for rapid turnover and a dimeric model of activated nuclear receptor.
The estrogen receptor in MCF-7 cells: evidence from dense amino acid labeling for rapid turnover and a dimeric model of activated nuclear receptor.
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MCF-7 细胞中的雌激素受体：来自快速周转的密集氨基酸标记和激活核受体二聚体模型的证据。
DOI：
10.1210/endo-115-4-1295
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发表时间：
1984
期刊：
影响因子：
4.8
通讯作者：
M. Lippman
中科院分区：
文献类型：
--
作者：
S. Scholl;M. Lippman
在37 ℃下用雌二醇处理MCF-7细胞时，几乎所有的雌激素受体都在核室中发现。这种核雌激素受体在高盐蔗糖密度梯度上形成接近5S的沉积物，类似于通过温和加热在体外激活的受体。提取核受体后，在我们的缓冲液条件下，5S形式在0-4 ℃下不稳定，并在10-14小时内转化为4S形式。在不存在雌二醇的情况下，将细胞在密集氨基酸的存在下孵育不同的时间，随后在37 ℃下用3 nM [3 H]雌二醇标记20- 30-min，通过其不同的沉降特性，允许在蔗糖梯度上分离新合成的雌激素受体。与新鲜的核提取物，我们观察到一个渐进的转变，以较重的形式在蔗糖梯度的时间在密集的氨基酸孵育成比例。随着细胞在浓培养基中孵育时间的增加，5S核受体逐渐变得更致密，并且峰从轻到重移动，而在中间时间点没有分解成离散的重和轻形式。与此相反，当将细胞与浓氨基酸孵育不同时间并用[3 H]雌二醇短暂处理后制备的核提取物在0-4 ℃静置10-14小时时，我们观察到重和轻受体的离散峰。在每个时间点分离成重链和轻链形式的离散峰，可以计算该受体的转换率（t1/2 =约2.25 h）。这些研究结果是一致的模型，其中5S核受体是随机关联的重和轻单体的低聚物，而老化的4S核受体是一个单体。我们从这些数据中得出结论，雌激素受体的合成是非常迅速的对数生长期MCF-7细胞，和激活的核受体似乎是一个寡聚体的至少两个单体密切相关的大小和代谢以类似的速度。不同单体（重链和轻链）之间的随机缔合导致核受体的宽峰，并且至少与作为受体活化的一部分发生的二聚化反应一致。
Upon treatment of MCF-7 cells with estradiol at 37 C, practically all of the estrogen receptor is found in the nuclear compartment. This nuclear estrogen receptor form sediments close to 5S on high salt sucrose density gradients, similar to receptor activated in vitro by gentle heating. Upon extraction of the nuclear receptor, this 5S form is not stable at 0-4 C under our buffer conditions and is converted to a 4S form in 10-14 h. Incubation of cells in the presence of dense amino acids for various amounts of time in the absence of estradiol, followed by a 20- to 30-min labeling period with 3 nM [3H]estradiol at 37 C, permits separation of the newly synthesized estrogen receptor on sucrose gradients by means of its different sedimentation properties. With the fresh nuclear extract, we observe a progressive shift to a heavier form on sucrose gradients in proportion to the time of incubation in dense amino acids. The 5S nuclear receptor gradually becomes denser as the time of incubation of cells in dense medium increases and the peak moves from light to heavy without resolving into discrete heavy and light forms at intermediary time points. In contrast, when the nuclear extract, prepared after varying periods of incubation of the cells with dense amino acids and brief treatment with [3H]estradiol, is left standing at 0-4 C for a period of 10-14 h, we observe discrete peaks of heavy and light receptors. The resolution into discrete peaks of heavy and light forms at each time point permits a calculation of the turnover rate for this receptor (t 1/2 = approximately 2.25 h). These findings are consistent with a model in which the 5S nuclear receptor is an oligomer of randomly associated heavy and light monomers, whereas the aged 4S nuclear receptor is a monomer. We conclude from these data that estrogen receptor synthesis is extremely rapid in log growth phase MCF-7 cells; and the activated nuclear receptor appears to be an oligomer of at least two monomers closely related in size and metabolized at a similar rate. The random association between different monomers (heavy and light) results in a broad peak of nuclear receptor and is at least consistent with a dimerization reaction occurring as part of receptor activation.
类固醇激素对卵清蛋白和伴清蛋白基因转录的调节。
DOI：
--
发表时间：
1981
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Palmiter,RD;Mulvihill,ER;Shepherd,JH;McKnight,GS
通讯作者：
McKnight,GS
雌激素受体复合物的核结合：受体特异性核受体位点。
影响因子：
4.8
作者：
Kon,OL;Spelsberg,TC
通讯作者：
Spelsberg,TC
DOI：
--
发表时间：
1983
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Raaka,BM;Samuels,HH
通讯作者：
Samuels,HH