PROGESTERONE RECEPTOR REGULATION

孕酮的作用，这是一种在控制 女性生殖组织的功能和生长，如乳房 和子宫，似乎是通过与细胞内的 蛋白质，孕激素受体(PR)。尽管人们已经知道了很多关于 这种蛋白质的性质，人们对它的合成和降解知之甚少 公关和调节这些比率的因素。我们的初步研究已经 为生物合成的、非激素结合的PR前体提供了证据 以及当PR与 抗孕激素RU486与孕激素。我们的目标是研究荷尔蒙因素 参与公关水平和营业额的调整，以进行调查 PR的生物合成前体，并检查核PR的性质 复合体。我们将使用密度平移技术来检查周转率 动力学受配体性质的影响(孕激素与 抗孕激素)和受体占有率水平。我们会比较一下 PR处于雌激素控制下的系统(MCF-7人乳腺癌 和大鼠子宫细胞)，不依赖雌激素(T47D人酿造 癌细胞)。我们将利用一个动力学模型，从这个模型中，PR 前体池大小和生物合成、活化和降解率 可以导出常量，我们将尝试对前身进行表征 使用抗PR的单抗。这些方法还将使我们能够 解决这一重要问题，即雌激素是否通过 受体合成、前体激活或稳定的变化 公共关系自从我们发现核内PR与抗孕激素的复合体 沉积物中6种S在与孕激素形成络合物的条件下 独家4号S，我们来考察一下影响6号S/4号S比例的因素， 用交联法测定6种S菌种的亚基组成 光亲和标记，并评价这6个S物种是否代表一个 非激活的非DNA结合形式的PR。这些研究应该提供新的 关于这一重要物质的生物合成和降解的信息 调节蛋白，以及可能构成基础的受体相互作用 孕激素拮抗剂作用。

The actions of progesterone, a hormone of central importance in controlling the function and growth of female reproductive tissues, such as the breast and uterus, appear to be mediated via interaction with an intracellular protein, the progesterone receptor (PR). Although much is known about the nature of this protein, little is known about the synthesis and degradation of PR and factors that regulate these rates. Our initial studies have provided evidence for a biosynthetic, non hormone-binding precursor of PR and for differences in the form of PR when it is associated with the antiprogestin RU486 vs progestin. Our aims are to study hormonal factors involved in regulation of PR levels and turnover, to investigate biosynthetic precursors of PR, and to examine the nature of nuclear PR complexes. We will use the density shift technique to examine how turnover kinetics are affected by the nature of the ligand (progestin vs antiprogestin) and the level of receptor occupancy. We will compare systems in which PR is under estrogen control (MCF-7 human breast cancer and rat uterine cells) and independent of estrogen (T47D human brease cancer cells). We will utilize a kinetic model, from which the PR precursor pool size and biosynthetic, activation and degradation rate constants can be derived, and we will attempt to characterize the precursor using monoclonal antibodies to PR. These approaches will also enable us to address the important issue of whether estradiol increases PR levels by changes in receptor synthesis, precursor activation, or stabilization of PR. Since we have found that nuclear PR complexes with antiprogestin sediment as 6 S species under conditions where the complexes with progestin are exclusively 4 S, we will examine factors that affect the 6 S/4 S ratio, determine the subunit composition of the 6 S species by crosslinking and photoaffinity labelling, and evaluate whether the 6 S species represents an "unactivated" non-DNA binding form of PR. These studies should provide new information on the biosynthesis and degradation of this important regulatory protein, and on the receptor interactions that may underlie progestin antagonist action.