大鼠NB2淋巴瘤细胞中G蛋白与催乳素受体的交联

Cross-linking of G-proteins to the prolactin receptor in rat NB2 lymphoma cells.

作者信息

Too C K, Shiu R P, Friesen H G

机构信息

Dept. of Physiology, University of Manitoba, Winnipeg, Canada.

出版信息

Biochem Biophys Res Commun. 1990 Nov 30;173(1):48-52. doi: 10.1016/s0006-291x(05)81019-8.

DOI:10.1016/s0006-291x(05)81019-8

PMID:2124115

Abstract

In Nb2 cell membranes, two guanine nucleotide-binding protein (G-protein) species (Mr 43.5 and 46.5 kD) were [32P]-ADP-ribosylated by cholera toxin, while a single protein (Mr 41.5 kD) was [32P]-ADP-ribosylated by pertussis toxin. Immunostaining indicated two immunoreactive prolactin (PRL) receptor moieties of 56 and 64 kD. Cross-linking with ethylene glyco bis[succinimidyl-succinate] (mol. length of 16.1 A) generated a high mol. wt., [32P]-ADP-ribosylated band of 140-160 kD which also showed immunoreactivity with antiserum to the PRL receptor. Other cross-linkers with shorter molecular lengths (8.6 - 11.4 A) were ineffective. These findings indicate that the Nb2 lactogen receptor is complexed with G-proteins and provide evidence for the role of G-proteins in mediating PRL-stimulated mitognesis in Nb2 cells.

摘要

在Nb2细胞膜中，两种鸟嘌呤核苷酸结合蛋白（G蛋白）（分子量分别为43.5和46.5 kD）被霍乱毒素进行了[32P] - ADP核糖基化，而一种单一蛋白质（分子量41.5 kD）被百日咳毒素进行了[32P] - ADP核糖基化。免疫染色显示出56 kD和64 kD的两个免疫反应性催乳素（PRL）受体部分。用乙二醇双[琥珀酰亚胺基琥珀酸酯]（分子长度为16.1 Å）进行交联产生了一条高分子量的140 - 160 kD的[32P] - ADP核糖基化条带，其也与PRL受体抗血清呈现免疫反应性。其他分子长度较短（8.6 - 11.4 Å）的交联剂无效。这些发现表明Nb2催乳素受体与G蛋白形成复合物，并为G蛋白在介导Nb2细胞中PRL刺激的有丝分裂作用提供了证据。