Anthony R V, Helmer S D, Sharif S F, Roberts R M, Hansen P J, Thatcher W W, Bazer F W
Department of Animal Science, University of Missouri, Columbia 65211.
Endocrinology. 1988 Sep;123(3):1274-80. doi: 10.1210/endo-123-3-1274.
Ovine and bovine trophoblast protein-1 (oTP-1 and bTP-1) are newly discovered proteins produced by embryonic tissues for a limited period in early gestation. They appear to act as agents that prevent regression of the corpus luteum during early pregnancy in the ewe and cow. Ovine TP-1 [mol wt (Mr), 17,000] consists of three or four isoelectric variants (pI 5.4-5.7), whereas bTP-1, which cross-reacts with antiserum to oTP-1, is found as two predominant Mr classes (Mr, 22,000 and 24,000), each with several isoelectric variants (in the pI range 6.3-6.8). Cell-free translation of ovine conceptus mRNA yields pre-oTP-1 also consists of three or four isoelectric variants, assumed to have arisen by translation of multiple mRNA species. Ovine TP-1 is not glycosylated. When bovine conceptus mRNA is translated, a group of four or five isoforms of pre-bTP-1 are generated, each with a Mr of 19,000. In the presence of microsomes the Mr shifts upward to about 21,500. Bovine conceptuses cultured in presence of either [3H]glucosamine or [3H]mannose incorporate label into both size classes of bTP-1 (Mr, 22,000 and 24,000). Culture in presence of [35S]methionine and tunicamycin gave rise to a nonglycosylated form of bTP-1 with an apparent Mr of 18,000. Treatment of [35S]methionine-labeled bTP-1 with either endoglycosidase-H or peptide:N-glycosidase F yielded products with Mr of 17,000 and 16,000, respectively. bTP-1, although functionally and structurally related to oTP-1, appears to be a glycoprotein carrying at least two Asn-linked oligosaccharides. The two Mr classes of bTP-1 arise as a result of differences in either the number or structure of the carbohydrate chains. Like oTP-1, bTP-1 is probably translated from multiple mRNA species.
绵羊和牛的滋养层蛋白-1（oTP-1和bTP-1）是胚胎组织在妊娠早期有限时间段内产生的新发现蛋白质。它们似乎起着防止母羊和母牛妊娠早期黄体退化的作用。绵羊TP-1[分子量（Mr），17,000]由三或四种等电变体（pI 5.4 - 5.7）组成，而与抗oTP-1抗血清发生交叉反应的bTP-1以两种主要的Mr类别（Mr，22,000和24,000）存在，每种都有几种等电变体（在pI范围6.3 - 6.8）。绵羊孕体mRNA的无细胞翻译产生的前体oTP-1也由三或四种等电变体组成，推测是由多种mRNA种类的翻译产生的。绵羊TP-1没有糖基化。当翻译牛孕体mRNA时，会产生一组四或五种前体bTP-1的同工型，每种的Mr为19,000。在微粒体存在的情况下，Mr向上移动到约21,500。在[3H]葡糖胺或[3H]甘露糖存在下培养的牛孕体将标记物掺入bTP-1的两种大小类别（Mr，22,并将其与抗oTP-1抗血清发生交叉反应的bTP-1以两种主要的Mr类别（Mr，22,000和24,000）存在，每种都有几种等电变体（在pI范围6.3 - 6.8）。绵羊孕体mRNA的无细胞翻译产生的前体oTP-1也由三或四种等电变体组成，推测是由多种mRNA种类的翻译产生的。绵羊TP-1没有糖基化。当翻译牛孕体mRNA时，会产生一组四或五种前体bTP-1的同工型，每种的Mr为19,000。在微粒体存在的情况下，Mr向上移动到约21,500。在[3H]葡糖胺或[3H]甘露糖存在下培养的牛孕体将标记物掺入bTP-1的两种大小类别（Mr，22,000和24,000）。在[35S]甲硫氨酸和衣霉素存在下培养产生了一种表观Mr为18,000的非糖基化形式的bTP-1。用内切糖苷酶-H或肽：N-糖苷酶F处理[35S]甲硫氨酸标记的bTP-1分别产生了Mr为17,000和16,000的产物。bTP-1虽然在功能和结构上与oTP-1相关，但似乎是一种携带至少两个天冬酰胺连接寡糖的糖蛋白。bTP-1的两种Mr类别是由于碳水化合物链的数量或结构差异而产生的。与oTP-1一样，bTP-1可能也是由多种mRNA种类翻译而来的。 000和24,000）。在[35S]甲硫氨酸和衣霉素存在下培养产生了一种表观Mr为18,000的非糖基化形式的bTP-1。用内切糖苷酶-H或肽：N-糖苷酶F处理[35S]甲硫氨酸标记的bTP-1分别产生了Mr为17,000和16,000的产物。bTP-1虽然在功能和结构上与oTP-1相关，但似乎是一种携带至少两个天冬酰胺连接寡糖的糖蛋白。bTP-1的两种Mr类别是由于碳水化合物链的数量或结构差异而产生的。与oTP-1一样，bTP-1可能也是由多种mRNA种类翻译而来的。
