通过免疫筛选对小鼠衰变加速因子进行分子克隆。

Molecular cloning of murine decay accelerating factor by immunoscreening.

作者信息

Fukuoka Y, Yasui A, Okada N, Okada H

机构信息

Department of Molecular Immunology, Tohoku University, Sendai, Japan.

出版信息

Int Immunol. 1996 Mar;8(3):379-85. doi: 10.1093/intimm/8.3.379.

DOI:10.1093/intimm/8.3.379

PMID:8671624

Abstract

Although the cDNA of human decay accelerating factor (DAF) which restricts complement activation on homologous cell membranes was cloned in 1987, all trials to detect the cDNA of mouse DAF by cross-hybridization were unsuccessful. However, by immunoscreening with a rabbit antiserum against purified mouse DAF, we successfully cloned the cDNA. It contains four typical short consensus repeats (SCR) similar to that in human and guinea pig DAF. The base sequence showed 63.7 and 63.8% identity to that of human and guinea pig DAF respectively. The deduced amino acid sequence identity to human and guinea pig DAF was 47.2 and 46.5% respectively. Mouse complement receptor related gene Y (Crry)/p65 function is comparable to DAF. SCR3 and SCR4 of mouse DAF showed 50% identity to SCR2 and SCR3 of Crry/p65 respectively. Identification of the mouse DAF gene should open a new approach for determining the actual in vivo role of DAF by analyzing autoimmune mice as well as generating DAF gene knockout mice using embryonic stem cells.

摘要

尽管1987年已克隆出限制同源细胞膜上补体激活的人衰变加速因子（DAF）的cDNA，但通过交叉杂交检测小鼠DAF的cDNA的所有尝试均未成功。然而，我们用抗纯化小鼠DAF的兔抗血清进行免疫筛选，成功克隆了该cDNA。它含有四个典型的短共有重复序列（SCR），类似于人和豚鼠DAF中的序列。碱基序列与人及豚鼠DAF的碱基序列分别显示出63.7%和63.8%的同一性。推导的氨基酸序列与人及豚鼠DAF的同一性分别为47.2%和46.5%。小鼠补体受体相关基因Y（Crry）/p65的功能与DAF相当。小鼠DAF的SCR3和SCR4与Crry/p65的SCR2和SCR3分别显示出50%的同一性。小鼠DAF基因的鉴定应为通过分析自身免疫小鼠以及利用胚胎干细胞产生DAF基因敲除小鼠来确定DAF在体内的实际作用开辟一条新途径。