Kemper B, Habener J F, Potts J T, Rich A
Proc Natl Acad Sci U S A. 1972 Mar;69(3):643-7. doi: 10.1073/pnas.69.3.643.
Biosynthesis of a precursor to bovine parathyroid hormone has been demonstrated in slices of parathyroid tissue incubated in vitro. The proparathyroid hormone is 15-20 amino acids larger than the bovine hormone, and has a molecular weight of about 11,500 as determined by polyacrylamide gel electrophoresis. Upon incubation of parathyroid slices with [(14)C]aminoacids, radioactivity is detected initially in the precursor. If incorporation of [(14)C]aminoacids is inhibited after a short incubation either by replacement of radioactive amino acids with unlabeled amino acids or by addition of puromycin, the amount of radioactivity in the precursor decreases, while the radioactivity in the hormone continues to increase. The precursor is bound by an antibody that is specific for parathyroid hormone, and its binding can be inhibited by addition of the hormone. Analysis of tryptic digests indicates that the precursor and the hormone have common tryptic peptides, and that there are at least two additional peptides in the precursor.
在体外培养的甲状旁腺组织切片中已证实了牛甲状旁腺激素前体的生物合成。甲状旁腺激素原比牛甲状旁腺激素多15 - 20个氨基酸，通过聚丙烯酰胺凝胶电泳测定其分子量约为11,500。将甲状旁腺切片与[¹⁴C]氨基酸一起孵育时，最初在前体中检测到放射性。如果在短时间孵育后通过用未标记氨基酸替换放射性氨基酸或添加嘌呤霉素来抑制[¹⁴C]氨基酸的掺入，前体中的放射性量会减少，而激素中的放射性会继续增加。前体被一种对甲状旁腺激素特异的抗体结合，并且添加该激素可抑制其结合。胰蛋白酶消化分析表明，前体和激素具有共同的胰蛋白酶肽段，并且前体中至少还有另外两种肽段。
