不同物种DNA甲基转移酶的多肽组成及免疫分析

Polypeptide composition and an immunological analysis of DNA methyltransferases from different species.

作者信息

Pfeifer G P, Kohlmaier L, Tomassetti A, Schleicher R, Follmann H, Pfohl-Leszkowicz A, Dirheimer G, Drahovsky D

机构信息

Zentrum der Biologischen Chemie, Universität Frankfurt, Federal Republic of Germany.

出版信息

Arch Biochem Biophys. 1989 Jan;268(1):388-92. doi: 10.1016/0003-9861(89)90599-7.

DOI:10.1016/0003-9861(89)90599-7

PMID:2463790

Abstract

The cross-reactivity of the monoclonal anti-human placental DNA methyltransferase antibody M2B10 with DNA methyltransferases isolated from other species was investigated. This antibody immunoprecipitates DNA methyltransferases from mammalian cells, i.e., human placenta, mouse P815 cells, and rat liver cells. No cross-reactivity is observed with DNA methyltransferases from wheat germ and with bacterial DNA methyltransferases HpaII and EcoRI. The mammalian enzymes are characterized by polypeptides of molecular mass 150-190 kDa. Polypeptides smaller than 190 kDa are presumably generated by proteolysis of the native 190-kDa DNA methyltransferase. Trypsin digestion of the 190-kDa polypeptide isolated from mouse cells results in progressive appearance of DNA methyltransferase polypeptides of 150-190, 110, 100, and 52-60 kDa.

摘要

研究了单克隆抗人胎盘DNA甲基转移酶抗体M2B10与从其他物种分离的DNA甲基转移酶的交叉反应性。该抗体可从哺乳动物细胞中免疫沉淀DNA甲基转移酶，即人胎盘、小鼠P815细胞和大鼠肝细胞。未观察到与来自小麦胚芽的DNA甲基转移酶以及细菌DNA甲基转移酶HpaII和EcoRI的交叉反应性。哺乳动物的这些酶的特征是分子量为150 - 190 kDa的多肽。小于190 kDa的多肽可能是由天然190 kDa的DNA甲基转移酶经蛋白水解产生的。从小鼠细胞中分离出的190 kDa多肽经胰蛋白酶消化后，会逐渐出现分子量为150 - 190 kDa、110 kDa、100 kDa和52 - 60 kDa的DNA甲基转移酶多肽。