Rutanen E M, Koistinen R, Seppälä M, Julkunen M, Suikkari A M, Huhtala M L
Department I of Obstetrics and Gynaecology, University Central Hospital, Helsinki, Finland.
J Steroid Biochem. 1987;27(1-3):25-31. doi: 10.1016/0022-4731(87)90290-1.
Two proteins, designated as PP12 and PP14 were originally isolated from soluble extracts of the human placenta and its adjacent membranes. We have shown that they are synthesized by decidualized/secretory endometrium and not by placenta. Both proteins occur at high concentrations in human amniotic fluid, which is therefore an excellent source for purification. PP12 is a 34-kDa glycoprotein, which has an N-terminal amino acid sequence of Ala-Pro-Trp-Gln-Cys-Ala-Pro-Cys-Ser-Ala. This is identical with that of somatomedin-binding protein purified from the amniotic fluid. PP12 too binds somatomedin-C, or IGF-I (insulin-like growth factor-I). Human secretory endometrium synthesizes and secretes PP12, and progesterone stimulates its secretion. PP14 is a 28-kDa glycoprotein. Its N-terminal sequence shows homology to that of beta-lactoglobulins from various species. We have found PP14 in the human endometrium, serum and milk. Immunologically, PP14 is related to progestagen-associated endometrial protein (PEP), alpha-2 pregnancy-associated endometrial protein (alpha-2, PEG), endometrial protein 15 (EP15), alpha-uterine protein (AUP) and chorionic alpha-2 microglobulin (CAG-2). In ovulatory menstrual cycles, the concentration of PP14 increases in endometrial tissue as the secretory changes advance. In serum, the PP14 concentration begins to rise later than the progesterone levels, and high serum PP14 levels are maintained for the first days of the next cycle. By contrast, no elevation of serum PP14 level is seen in anovulatory cycles. Our results show that progesterone-associated proteins are synthesized by the human endometrium and appear in the peripheral circulation, where they can be quantitatively measured using immunochemical techniques.
最初从人胎盘及其相邻膜的可溶性提取物中分离出两种蛋白质，分别命名为PP12和PP14。我们已经表明它们是由蜕膜化/分泌型子宫内膜合成的，而不是由胎盘合成。这两种蛋白质在人羊水中的浓度都很高，因此羊水是纯化的极佳来源。PP12是一种34 kDa的糖蛋白，其N端氨基酸序列为Ala-Pro-Trp-Gln-Cys-Ala-Pro-Cys-Ser-Ala。这与从羊水中纯化的生长调节素结合蛋白的序列相同。PP12也结合生长调节素-C或胰岛素样生长因子-I（IGF-I）。人分泌型子宫内膜合成并分泌PP12，孕酮刺激其分泌。PP14是一种28 kDa的糖蛋白。其N端序列与来自不同物种的β-乳球蛋白的序列具有同源性。我们在人子宫内膜、血清和乳汁中发现了PP14。从免疫学角度来看，PP14与孕激素相关子宫内膜蛋白（PEP）、α-2妊娠相关子宫内膜蛋白（α-2，PEG）、子宫内膜蛋白15（EP15）、α-子宫蛋白（AUP）和绒毛膜α-2微球蛋白（CAG-2）有关。在排卵性月经周期中，随着分泌期变化的推进，子宫内膜组织中PP14的浓度会增加。在血清中，PP14浓度开始升高的时间比孕酮水平晚，并且在下一个周期的头几天维持在高水平。相比之下，在无排卵周期中未观察到血清PP14水平升高。我们的结果表明，孕激素相关蛋白是由人子宫内膜合成并出现在外周循环中，在那里可以使用免疫化学技术进行定量测量。
