质谱法分析大肠癌组织中亲核蛋白A的蛋白质变体  

Mass Spectrometric Analysis of Proteoforms of Cyclophilin A from Human Colorectal Carcinoma Tissues

作　　者：洪欣[1] 乔璐 杨静波[3] 孙晓盈[2] 王海[2] 何成彦[2] 

机构地区：[1]吉林大学中日联谊医院血管外科,长春130033 [2]吉林大学中日联谊医院检验科,长春130033 [3]吉林大学第二医院医学研究中心,长春130014

出　　处：《分析化学》2018年第2期195-202,共8页Chinese Journal of Analytical Chemistry

基　　金：国家自然科学基金项目(No.81572082);吉林省科技厅项目(Nos.20150414015GH;2011713)资助~~

摘　　要：采用超滤、亲和层析和双向电泳分离并纯化了人大肠癌组织中的亲核蛋白,结合蛋白印迹分析,发现亲核蛋白存在几个蛋白质变体的现象。采用基质辅助激光解吸电离-飞行时间质谱以及电喷雾串联质谱技术,对亲核蛋白的主要蛋白质变体的胰酶水解肽段进行了一级结构的解析,发现大肠癌组织中的亲核蛋白主要存在N端乙酰化(Ac-1Met及脱去N端甲硫氨酸后的Ac-2Val)、5Thr的磷酸化等修饰状态,这些修饰形式单独或者相互组合构成了亲核蛋白的主要蛋白质变体。此外,在亲核蛋白中还发现一些氧化修饰和脱氨基修饰的情况。研究表明,利用质谱及串联质谱技术,能够快速、准确地鉴定人大肠癌组织中分离得到的亲核蛋白的几种蛋白质变体。Cyclophilin A was isolated from human colorectal carcinoma tissues by ultrafiltration,affinity chromatography,and two dimensional electrophoresis. By the aid of Western blot analysis,several isoforms of cyclophilin A were detected.,The tryptic digests from cyclophilin A were analyzed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry as well as electrospray tandem mass spectrometry techniques. Several different modifications such as N-terminal acetylation( Ac-1Met and Ac-2Val) and phosphorylation of5 Thr were identified from these isoforms of cyclophilin A,which represented the majority of the proteoforms of cyclophilin A in this study. In addition,other kinds of modifications such as oxidation and deamidation were also found in these proteoforms. The results indicated that the developed method could be used to rapidly and correctly identify the several proteoforms of cyclophilin A isolated from human colorectal carcinoma tissues.

关 键 词：质谱 亲核蛋白 大肠癌 乙酰化 磷酸化 

分 类 号：O657.63[理学—分析化学] R735.34[理学—化学]