Glycyl glutamine, an inhibitory neuropeptide derived from β-endorphin
Glycyl glutamine, an inhibitory neuropeptide derived from β-endorphin
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DOI：
10.1038/306267a0
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发表时间：
1983-11
期刊：
影响因子：
64.8
通讯作者：
D. Parish;D. Smyth;J. Normanton;J. Wolstencroft
中科院分区：
文献类型：
--
作者：
D. Parish;D. Smyth;J. Normanton;J. Wolstencroft
细胞内激素原激活的主要机制似乎涉及连续碱性残基序列的蛋白水解裂解1。因此，所有已知的源自促肾上腺皮质激素前体和β-内啡肽的生物活性肽似乎最初都被具有这种特异性的酶切除。C-末端肽β-内啡肽（1-31）通过在赖氨酰精氨酸序列处裂解产生，另外的裂解可产生相关肽β-内啡肽（1-27）和β-内啡肽（1-26）。β-内啡肽的这些衍生物是由内肽酶释放的，内肽酶似乎催化成对赖氨酸残基羧基侧的裂解，随后是羧肽酶B样酶的作用（图1）。β-内啡肽片段β-内啡肽（1-27）和β-内啡肽（1-26）已从猪2 - 4和牛垂体5中分离得到，但C-末端二肽甘氨酰谷氨酰胺以前未见报道。在这里，我们描述了甘氨酰谷氨酰胺的分离，从猪垂体和目前的证据，其存在于羊脑干。当将该二肽以离子电泳方式应用于大鼠脑干神经元时，该二肽对细胞放电表现出抑制作用。
The primary mechanism of activation of intracellular prohormones seems to involve proteolytic cleavage at sequences of consecutive basic residues1. Thus, all the known biologically active peptides derived from the prohormone of corticotropin andβ-endorphin appear to be excised initially by enzymes with this specificity. The C-terminal peptide,β-endorphin (1–31), is generated by cleavage at a lysyl arginine sequence and an additional cleavage can give rise to the related peptides,β-endorphin (1–27) andβ-endorphin (1–26). These derivatives ofβ-endorphin are released by an endopeptidase that appears to catalyse cleavage on the carboxyl side of paired lysine residues, followed by the action of a carboxypeptidase B-like enzyme (Fig. 1). Theβ-endorphin fragments,β-endorphin (1–27) andβ-endorphin (1–26), have been isolated from porcine2–4and bovine pituitary5but the C-terminal dipeptide, glycyl glutamine, has not been reported previously. Here we describe the isolation of glycyl glutamine from porcine pituitary and present evidence for its presence in sheep brain stem. When applied ionophoretically to brain stem neurones in the rat, the dipeptide exhibited an inhibitory action on cell firing.