连接介导PCR分析线粒体DNA的氧化损伤频率及损伤热点  

Analysis of the frequency and hot spot of mitochondrial DNA oxidative damage by ligation mediated PCR

作　　者：刘力[1] 庄志雄[2] 陈雯[1] 杨杏芬[1] 凌文华[1] 魏青[1] 邓丽霞[1] 

机构地区：[1]中山医科大学公共卫生学院卫生毒理学教研室,510089 [2]深圳市卫生防疫站

出　　处：《中华劳动卫生职业病杂志》2000年第3期151-154,共4页Chinese Journal of Industrial Hygiene and Occupational Diseases

摘　　要：目的　论证线粒体DNA(mitochondrial,mtDNA)“常见缺失”与DNA氧化损伤的关系。方法　采用连接介导PCR(ligationmediatedPCR ,LMPCR) ,在大鼠肝细胞株 (BRL 3A)暴露于 5 0mmol/L过氧化氢 (H2 O2 )形成氧化损伤后 ,分析该缺失的断裂区段 (80 71～ 8190 ,约 12 0bp)内 ,各核苷酸氧化损伤的频率及热点。结果　在 80 71～ 8190区段 ,存在 8181G、8182G两个明显的氧化损伤热点 ,810 8C及80 96～ 810 1(6bp)的损伤亦明显 ;而“常见缺失”的断裂位点 (8118T)并未被明显氧化损伤。其中 ,8181G/ 8182G位于一个DNA重复结构内 ,80 96～ 810 1(6bp)则位于一个DNA回文结构内。结论　线粒体DNA“常见缺失”的断裂位点不一定是氧化损伤的热点 ,但在断裂区段内存在Objective To study the relationship between the common deletion and oxidative damage of mitochondrial DNA(mtDNA). Methods The ligation mediated PCR(LMPCR) was used to map the frequency and hot spot of oxidative damage in the 5' end breakpoint region(8071～8190,about 120 bp) among the common deletion in the heavy strand of mtDNA from rat liver BRL 3A cell line exposed to 50 mmol/L of hydrogen peroxide(H 2O 2). Results Two oxidative damage hot spots were located in 8181G and 8182G.The regions in 8108C and 8096～8101(6 bp) were also severely damaged.The hot spots mapped in this study were surprisingly not the break point(8118T) of the common deletion. Conclusion The break point of common deletion in mtDNA is not necessarily the hot spot of oxidative damage.However,two hot spots were found in DNA break region.

关 键 词：线粒体DNA 常见缺失 连接介导PCR DNA氧化损伤 

分 类 号：R135.1[医药卫生—劳动卫生]