Schwartz T W, Sheikh S P, O'Hare M M
Laboratory for Molecular Endocrinology, University Department of Clinical Chemistry, Rigshopitalet, Denmark.
FEBS Lett. 1987 Dec 10;225(1-2):209-14. doi: 10.1016/0014-5793(87)81159-6.
Pancreatic polypeptide (PP) and neuropeptide Y (NPY) belong to a family of regulatory peptides which hold a distinct tertiary structure, the PP-fold, even in dilute aqueous solution. High-affinity receptors, specific for both PP and NPY, are described on the rat phaeochromocytoma cell line, PC-12. The binding of [125I-Tyr36]PP to PC-12 cells was inhibited by concentrations of unlabeled PP which correspond to physiological concentrations of the hormone, 10(-11)-10(-9) mol/l. The affinity of the receptor for the neuropeptide, NPY, was 10(2)-times lower than that of the PP receptor. C-terminal fragments of both PP (PP24-36) and NPY (NPY13-36) were between 10(2)- and 10(3)-times less potent in displacing the radiolabeled 36-amino-acid peptides from their respective receptors. It is concluded that PC-12 cells are suited for structure-function studies of the PP-fold peptides and studies on the cellular events following cellular binding of PP-fold peptides.
胰多肽（PP）和神经肽Y（NPY）属于一类调节肽家族，即使在稀水溶液中也具有独特的三级结构，即PP折叠。在大鼠嗜铬细胞瘤细胞系PC-12上发现了对PP和NPY均具有特异性的高亲和力受体。[125I-Tyr36]PP与PC-12细胞的结合受到未标记PP浓度的抑制，这些浓度与激素的生理浓度（10^(-11)-10^(-9)mol/L）相对应。该受体对神经肽NPY的亲和力比对PP受体的亲和力低10^2倍。PP（PP24-36）和NPY（NPY13-36）的C末端片段在从各自受体上置换放射性标记的36氨基酸肽方面的效力比其低10^2至10^3倍。结论是PC-12细胞适用于PP折叠肽的结构-功能研究以及PP折叠肽细胞结合后细胞事件的研究。
