先天性全白内障晶状体和透明晶状体蛋白双向电泳差异比较

Analysis of two-dimensional electrophoresis maps of congenital total cataractous and normal lens proteins

目的 应用双向电泳（2-DE）技术分析先天性全白内障晶状体和正常透明晶状体蛋白质组成的差异.方法 采用固相pH梯度（IPG）等电聚焦2-DE技术分离全白内障组和正常对照组的晶状体蛋白后,比较两组蛋白质的组成差异.结果 人眼晶状体蛋白的主要分布在等电点（pI）5～9,相对分子质量14 000～90 000的范围内,高丰度的蛋白主要集中在pI 6～8,相对分子质量14 000～30 000之间.在pI 5.0～7.25,相对分子质量50 000～80 000的高分子量区间全白内障组具有较多的蛋白表达,在pI 6.7～7.7,相对分子质量19 000～29 000间的区域,全白内障组的部分正常蛋白点消失,在pI 7.1～7.6,相对分子质量15 000～17 000区间存在一些新的小分子量的蛋白点.结论 应用2-DE技术能够较好地分离人眼晶状体蛋白,全白内障组高分子量的蛋白质成分明显多于正常对照组,全白内障组的部分正常晶状体蛋白发生缺失,出现新的小分子量的蛋白成分.

Objective The protein changes of crystallins occur in congenital total cataract due to hereditary gene variation. To analyze the proteome alteration using two-dimensional electrophoresis （2-DE） is of important significance for exploring the pathogenesis of cataract. We compared the proteome of congenital total cataractous and normal lens using 2-DE. Methods The proteins of the congenital total cataract obtained from cataract surgery in 3 patients and 3 normal lens from eye bank and lens operation were separated using immobilized pH gradients 2-DE. Image analysis was carried out using Image Master 2D Platinum 5.0 software package. Results The 2-DE maps showed that human lens proteins appeared in the section of pI 5 -9 and the molecular weight was 14 000 -90 000 ; while more abundant lens proteins were in the section of pI 6 -8 with the molecular weight of 14 000 -30 000. An average of 136 ± 12 protein spots were detected by Image Master analysis software in the normal group and 199 ± 23 protein spots in the cataract group. More spots in the cataract lens protein map were detected in the section of pI 5.0 - 7.25 with the molecular weight 50 000 - 80 000. Some spots found in normal lens in pI 6. 7 - 7.7 and molecular weight 19 000 - 29 000 were absent in the cataractous lens. That showed in spots in the section of pI 7.1 - 7. 6 and molecular weight 15 000 - 17 000. Conclusion The 2-DE can efficiently separate the human lens proteins. High molecular weight proteins are more numerous in congenital total cataractous lens than in normal lens ; some normal lens proteins are not found and some new spots are detected in the congenital total cataractous.