牛肾上腺髓质中儿茶酚胺生物合成酶的亚细胞生物合成位点。

Subcellular site of biosynthesis of the catecholamine biosynthetic enzymes in bovine adrenal medulla.

作者信息

Sabban E L, Goldstein M

出版信息

J Neurochem. 1984 Dec;43(6):1663-8. doi: 10.1111/j.1471-4159.1984.tb06093.x.

DOI:10.1111/j.1471-4159.1984.tb06093.x

Abstract

The subcellular site of biosynthesis of the catecholamine biosynthetic enzymes was examined. Free and membrane-bound polysomes were prepared from bovine adrenal medulla and mRNA was isolated from these polysomes. Both were active in directing cell-free translations. Immunoprecipitation of cell-free products with specific antisera localized the biosynthesis of the subunits of tyrosine hydroxylase (TH) (apparent Mr = 61,000) and of phenylethanolamine N-methyltransferase (PNMT) (apparent Mr = 32,000) on free polysomes, compared with biosynthesis of subunits of dopamine beta-hydroxylase (DBH) (apparent Mr = 67,000) on membrane-bound polysomes. Cross-reactivity between translation products was observed. Antibodies for DBH recognized a polypeptide with electrophoretic mobility identical to newly synthesized PNMT. However increasing concentrations of antibodies to DBH recognized at most 1/20 of the PNMT formed. The results of this study show the subcellular distribution of the catecholamine synthesizing enzymes is determined by their site of biosynthesis.

摘要

对儿茶酚胺生物合成酶的亚细胞生物合成位点进行了研究。从牛肾上腺髓质制备游离和膜结合多核糖体，并从这些多核糖体中分离出mRNA。二者在无细胞翻译指导方面均具有活性。用特异性抗血清对无细胞产物进行免疫沉淀，结果显示酪氨酸羟化酶（TH）（表观分子量 = 61,000）和苯乙醇胺N - 甲基转移酶（PNMT）（表观分子量 = 32,000）的亚基生物合成定位于游离多核糖体上，而多巴胺β - 羟化酶（DBH）（表观分子量 = 67,000）的亚基生物合成则定位于膜结合多核糖体上。观察到翻译产物之间存在交叉反应。DBH抗体识别出一种电泳迁移率与新合成的PNMT相同的多肽。然而，DBH抗体浓度增加时，最多只能识别所形成的PNMT的1/20。本研究结果表明，儿茶酚胺合成酶的亚细胞分布由其生物合成位点决定。