电离辐射对人外周血线粒体编码基因mRNA表达的影响

目的： 观察γ射线对人外周血线粒体编码基因mRNA表达水平的影响，探讨线粒体编码基因用于辐射生物剂量估算的可行性。方法：用不同剂量水平 (0~5 Gy)的60Co γ射线照射3名正常人离体外周血样本，照射6 h后，提取总RNA，应用实时荧光定量PCR技术检测ND1，ND6，细胞色素C氧化酶亚基 (cytochrome C oxidase subunit，COX)I、II、III，三磷酸腺苷酶6 (adenosine triphosphatase，ATPase6)，三磷酸腺苷酶8(adenosine triphosphatase，ATPase8) mRNA表达水平的变化，采用Origin 7.5拟合照射剂量与基因表达水平的剂量-效应关系曲线。结果：γ射线照射人外周血后，线粒体编码基因COXI及 ATPase6的相对表达水平在0~5 Gy剂量范围内表达先增加，3 Gy剂量点之后显现下降趋势，对这两个基因在0~3 Gy剂量范围内分别进行拟合，得到COXI 剂量-效应关系方程为Y=0.625 9+0.256 1D (r2=0.916 3，P<0.01)； ATPase6基因表达剂量-效应关系方程为Y=0.218 9+ 0.806 0 D (r2=0.912 6，P<0.01)，其他5个基因的相对表达水平与照射剂量间不存在明显的剂量-效应关系 (P>0.05)。结论：γ射线对人外周血线粒体编码基因COXI 及 ATPase6的mRNA表达水平具有明显的影响，这两个基因的表达水平与γ射线的照射剂量存在线性关系，有望用于辐射生物剂量的估算。

Effects of radiation on mitochondrial gene expression in human peripheral blood cells

OBJECTIVE:To explore the effect of ionizing radiation on mitochondrial gene expression in human peripheral blood cells. METHODS：Human peripheral blood samples were exposed to 60Co γ-ray at different doses，and its RNA was isolated from the white cells. The relative real-time quantitative PCR by standard curve method was set up using β-actin as internal standards. With this method，ND1，ND6，COXI，COXII，COXIII，ATPase6， ATPase8 gene expression changes after ionizing radiation wererecorded，the relationship between mitochondrial gene expression and dose was analyzed by software of origin 7.5.RESULTS：The gene expression of COXI and ATPase6 after radiation of peripheral blood cells increased with the irradiation doses. From 0-3 Gy range，the relationship between the ratio of COXI mRNA/β-actin could be represented as：Y=0.625 9+0.256 1 D (r2=0.916 3，P<0.01)，the ATPase6 mRNA/ β-actin was：Y=0.218 9+ 0.806 0 D (r2=0.912 6，P<0.01).The relationship between the ratio of other mRNA/β-actin was not statistically different (P>0.05). CONCLUSION：Differential expression of COXI，ATPase6 mRNA was induced by ionizing radiation，so COXI and ATPase6 could be promising radiation biological dosimeters.