新基因LRP15参与紫外线诱导的DNA损伤的修复作用

目的探讨LRP15基因在K562细胞中对紫外线诱导的DNA损伤的修复作用，以进一步研究该基因的功能。方法利用真核表达质粒pcDNA3．1构建LRP15基因开放阅读框架（ORF）序列的正义及反义重组质粒；两种质粒经阳性脂质体介导法分别转染K562细胞，G418筛选阳性克隆；采用单细胞凝胶电泳（SCGE）技术观察两组细胞对紫外线诱导的DNA损伤的修复作用的差异。结果PCR鉴定证实，正义及反义重组质粒中LRP15基因ORF序列均按预定方向正确插入；SCGE实验表明，经紫外线照射后两组细胞的DNA基础损伤无明显差异（P=0.156）。但经45及90min修复后实验组细胞的DNA迁移长度明显小于对照细胞（P〈0．001）。结论成功构建LRP15基因的正义及反义真核表达质粒；LRP15基因对紫外线诱导的DNA损伤具有修复作用，可能是一个DNA修复基因。

Gene LRP15, a novel gene involved in repairing UV-induced DNA damage

Objective To explore the possible function of a novel gene LRP15 in repairing UV-induced DNA damage.Method Recombinant vectors containing the sense/antisense open reading frame (ORF) of LRP15 gene were constructed with a pcDNA3.1 eukaryotic expression vector. K562 cells were transfected with these two kinds of recombinant vectors by Superfect®. The transfected cells were chosen by geneticin (G418). The single cell gel electrophroesis (SCGE) assay was used to detect UV-induced DNA damage. Result The sense/antisense LRP15 recombinants were both successfully obtained with the molecular biological technique. The basal DNA damage of the experimental group was similar to that of the control group after UV exposure(P=0.156). But significant difference in DNA migration lengths was observed between the two groups at 45 min and 90 min after UV exposure(P<0.001). Conclusions The two kinds of eukaryotic expression vectors containing the sense/antisense LRP15 gene was successfully constructed. The study also suggests that the novel gene LRP15 may be a candidate for DNA repair gene playing an important role in repairing the UV-induced DNA damage.