神经内分泌伴侣蛋白7B2可增强激素原转化酶PC2在体外对阿黑皮素原的切割作用。

The neuroendocrine chaperone 7B2 can enhance in vitro POMC cleavage by prohormone convertase PC2.

作者信息

Braks J A, Martens G J

机构信息

Department of Animal Physiology, University of Nijmegen, The Netherlands.

出版信息

FEBS Lett. 1995 Sep 4;371(2):154-8. doi: 10.1016/0014-5793(95)00915-v.

DOI:10.1016/0014-5793(95)00915-v

PMID:7672117

Abstract

We previously showed that the neuroendocrine polypeptide 7B2 transiently interacts with prohormone convertase PC2 in the secretory pathway of neuroendocrine cells. Here we demonstrate that the processed, but not the intact, form of 7B2 can enhance the in vitro cleavage of newly synthesized prohormone proopiomelanocortin (POMC) in lysates of Xenopus intermediate pituitary cells. PC2 is presumably the cleavage enzyme involved since intact 7B2 abolishes the enhancing effect of processed 7B2 and is known to act as a specific inhibitor of PC2. Furthermore, processed 7B2 stimulates in vitro POMC cleavage by immunopurified Xenopus PC2. Our results indicate that 7B2 can display chaperone activity towards PC2.

摘要

我们之前发现，神经内分泌多肽7B2在神经内分泌细胞的分泌途径中与激素原转化酶PC2发生短暂相互作用。在此我们证明，经过加工的而非完整形式的7B2能够增强非洲爪蟾垂体中间叶细胞裂解液中新合成的激素原阿黑皮素原（POMC）的体外裂解。PC2可能是参与其中的裂解酶，因为完整的7B2会消除经过加工的7B2的增强作用，且已知其可作为PC2的特异性抑制剂。此外，经过加工的7B2可刺激经免疫纯化的非洲爪蟾PC2进行体外POMC裂解。我们的结果表明，7B2对PC2可表现出伴侣活性。