红细胞分化相关基因敲除小鼠对低剂量辐射损伤敏感性的研究

发布时间：2018-05-18 23:36

本文选题：小鼠 + 基因敲除　；参考：《军事医学》2015年06期

【摘要】：目的构建红细胞分化相关基因(EDAG)敲除小鼠并研究其对低剂量辐射损伤的敏感性。方法利用锌指核酸酶技术(ZFNs)建立EDAG敲除小鼠模型;通过外周血细胞计数、骨髓细胞的DNA损伤和集落形成能力评价低剂量辐射损伤。对野生型及EDAG敲除小鼠进行剂量率为0.31 Gy/min的X线照射,1 min/d,连续照射7 d,小鼠累计照射剂量为2.17 Gy。在X线照射后第1、3、5、7天称重并进行血常规检测(n=7);照射后第3天分离小鼠骨髓细胞,利用免疫荧光实验检测DNA损伤标志物p-H2A.x的表达水平(n=3);照射后第5天分离小鼠骨髓细胞,接种集落并于7 d后进行集落计数(n=3)。结果成功建立了EDAG敲除小鼠模型并在蛋白水平进行了敲除效果的鉴定;X线照射后第3天,与野生型相比,EDAG敲除小鼠白细胞明显减少,敲除小鼠骨髓细胞DNA损伤标志物p-H2A.x表达水平增加;X线照射7 d后骨髓细胞的集落形成能力降低。结论研究发现EDAG敲除小鼠对低剂量辐射诱导的损伤更加敏感,表现为血细胞数量减少,骨髓细胞成集落能力下降,DNA损伤增加。表明EDAG敲除小鼠作为一种对辐射高度敏感的动物模型,可作为低剂量辐射损伤生物学效应评价的有力工具。
[Abstract]:Objective to construct erythrocyte differentiation related gene (EDAG) knockout mice and study its sensitivity to low dose radiation injury. Methods EDAG knockout mice model was established by zinc-finger nuclease technique, and low dose radiation damage was evaluated by peripheral blood cell count, DNA damage and colony forming ability of bone marrow cells. Wild type and EDAG knockout mice were irradiated at a dose rate of 0.31 Gy/min for 1 min / d for 7 days, and the cumulative dose was 2.17 Gy. The mice bone marrow cells were isolated on the third day after irradiation, and the expression level of the DNA damage marker p-H2A.x was detected by immunofluorescence assay. The bone marrow cells were isolated on the 5th day after irradiation. The colony was inoculated and counted 7 days later. Results the mouse model of EDAG knockout was successfully established and the effect of knockout was confirmed at the protein level. On the 3rd day after irradiation, the leukocyte of EDAG knockout mice was significantly decreased compared with that of wild type mice. The expression level of DNA damage marker p-H2A.x in knockout mice increased the colony forming ability of bone marrow cells decreased after X-ray irradiation for 7 days. Conclusion the EDAG knockout mice were more sensitive to the damage induced by low dose radiation, showing that the number of blood cells decreased, the colony forming ability of bone marrow cells decreased and the damage of bone marrow cells increased. As a highly sensitive animal model, EDAG knockout mice can be used as a powerful tool to evaluate the biological effects of low dose radiation damage.
【作者单位】：天津大学化工学院;军事医学科学院放射与辐射医学研究所;
【基金】：国家自然科学基金资助项目(30570781,81222005)
【分类号】：R811.5

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