Jungblut P W, Hekim N, Meyer H H, Sierralta W D, Szendro P I
J Clin Chem Clin Biochem. 1983 Aug;21(8):473-80. doi: 10.1515/cclm.1983.21.8.473.
More than half of the extranuclear receptor content of resting cells is associated with cytoplasmic structures. Subfractionation of microsomes reveals a preponderance of "basic" (low electrophoretic mobility) receptor in rough endoplasmic reticulum. Surfynol-dithiothreitol extracts of smooth membranes are rich in "acidic" (high electrophoretic mobility) receptor. Trypsin increases the yields up to seven-fold, and this increase is correlated (r = 0.993) with the acidic receptor content and 5'-nucleotidase activity of these microsomal preparations. Acidic microsomal "cytosolic" and nuclear receptor can be degraded to the "basic" variety of streptomyces hyaluronidase. All forms give rise to a tryptic fragment with unchanged affinity for oestradiol and dimerization ability. Basic receptor isolated after enzymatic conversion of acidic receptor is microheterogenous on isoelectric focusing, but gives rise to only one precipitation arc versus the IgG fraction of a polyclonal antiserum. The precipitation arc can be recharged with labelled oestradiol and autoradiographed. Non-immune IgG's from (unspecific) soluble complexes with oestrogen receptors, but not with their tryptic fragments. The polyclonal antioestrogen receptor IgG fraction precipitates the oestradiol-tagged tryptic receptor fragment from all subcellular sources of all homologous (porcine) and heterologous (human, ovine, bovine, goat, rabbit, guinea pig, rat) target tissues tested. Organ specificity can therefore be excluded and a high degree of phylogenetic conservation of the oestrogen receptor's protein moiety is implied. The presence, in the immune IgG fraction, of steroid releasing antibodies, which apparently distort the binding site, should spur the search for monoclonal antibodies with similar properties.
静息细胞中超过一半的核外受体与细胞质结构相关。微粒体的亚分级分离显示，粗面内质网中存在大量“碱性”（低电泳迁移率）受体。光滑膜的Surfynol-二硫苏糖醇提取物富含“酸性”（高电泳迁移率）受体。胰蛋白酶可使产量提高至7倍，且这种增加与这些微粒体制剂的酸性受体含量和5'-核苷酸酶活性相关（r = 0.993）。酸性微粒体“胞质”和核受体可被降解为透明质酸链霉菌的“碱性”变体。所有形式都会产生一个对雌二醇亲和力和二聚化能力不变的胰蛋白酶片段。酸性受体经酶促转化后分离出的碱性受体在等电聚焦时具有微异质性，但与多克隆抗血清的IgG组分相比，仅产生一条沉淀弧。沉淀弧可用标记的雌二醇重新标记并进行放射自显影。非免疫IgG可与雌激素受体的（非特异性）可溶性复合物结合，但不能与它们的胰蛋白酶片段结合。多克隆抗雌激素受体IgG组分可沉淀来自所有测试的同源（猪）和异源（人、羊、牛、山羊、兔、豚鼠、大鼠）靶组织的所有亚细胞来源的雌二醇标记的胰蛋白酶受体片段。因此可以排除器官特异性，并暗示雌激素受体蛋白部分具有高度的系统发育保守性。免疫IgG组分中存在明显扭曲结合位点的类固醇释放抗体，这应促使人们寻找具有类似性质的单克隆抗体。
