中华皮肤科杂志 ›› 2010, Vol. 43 ›› Issue (9): 629-632.

• 论著 • 上一篇    下一篇

UVB对Jurkat细胞Gadd45a表达和DNA甲基化水平的影响

李亚萍1,赵明2,陆前进2   

  1. 1. 中南大学湘雅二医院皮肤科
    2.
  • 收稿日期:2010-03-22 修回日期:2010-05-16 发布日期:2010-09-10
  • 通讯作者: 陆前进 E-mail:dermatology2007@yahoo.cn

Effects of ultraviolet B （UVB） on the expression of Gadd45a gene and DNA methylation level in Jurkat cells

  • Received:2010-03-22 Revised:2010-05-16 Published:2010-09-10

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摘要：

目的 探讨中波紫外线（UVB）对Jurkat细胞Gadd45a表达和DNA甲基化水平的影响。方法 分别以UVB 1.0 J/cm2和1.5 J/cm2照射Jurkat细胞后，于6、12、24、48 h收集细胞，采用实时定量 RT-PCR法检测Gadd45a mRNA水平和甲基化敏感基因 CD11a、CD70 mRNA水平，同时检测Jurkat细胞基因组DNA总体甲基化水平的变化。结果 ①和照射前Jurkat细胞比较，UVB 1.0 J/cm2照射后6、12、24、48 h Jurkat细胞Gadd45a mRNA水平升高，以照射后6、12 h差异有统计学意义（P < 0.01，P < 0.05）。UVB 1.0 J/cm2照射后，甲基化敏感基因CD11a、CD70 mRNA水平也升高，以照射后12 h差异有统计学意义（P值均 < 0.05）。②以UVB 1.5 J/cm2照射Jurkat细胞，和照射前Jurkat细胞比较，照射后6、12、24、48 h，Jurkat细胞Gadd45a、CD11a、CD70 mRNA水平均显著升高（P < 0.05或P < 0.01）。③和照射前Jurkat细胞比较，Jurkat细胞经UVB 1.0 J/cm2照射后6、12、24、48 h总体甲基化水平降低，照射后6、12 h甲基化水平差异有统计学意义（P < 0.05，P < 0.01）。Jurkat细胞经UVB 1.5 J/cm2照射后6、12、24、48 h的总体甲基化水平显著降低，差异均有统计学意义（P值分别 < 0.01、< 0.01、< 0.01、< 0.05）。④UVB照射后Jurkat细胞的Gadd45a mRNA和DNA总体甲基化水平呈显著负相关（r = -0.395，P < 0.05）。结论 UVB能诱导Jurkat细胞Gadd45a表达上调，同时Jurkat细胞基因组DNA发生低甲基化。

关键词: 【关键词】紫外线, Jurkat细胞, Gadd45a, 甲基化

Abstract:

Objective To explore the effects of UVB on the expression of Gadd45a gene and DNA methylation levels in Jurkat cells. Methods Jurkat cells were irradiated with UVB of 1.0 J/cm2 and 1.5 J/cm2 respectively, and collected at 6, 12, 24 and 48 hours after the irradiation. Real-time RT-PCR was used to detect the mRNA expression of Gadd45a gene and methylation-sensitive genes CD11a and CD70. Global methylation level was also measured by MethylAmp global DNA methylation quantification kit. Results After irradiation with UVB at 1.0 J/cm2, the mRNA level of Gadd45a increased but global methylation level decreased at 6, 12, 24 and 48 hours, and significant changes were observed at 6 and 12 hours for the level of both Gadd45a mRNA expression and global methylation （P < 0.01 or 0.05）. Elevated mRNA expressions of CD11a and CD70 were also noted in Jurkat cells after irradiation with UVB of 1.0 J/cm2, and significant elevation was observed at 12 hours （both P < 0.05）. After irradiation with UVB of 1.5 J/cm2, there was a statistical increase in the mRNA expressions of Gadd45a, CD11a, CD70, together with a statistical decrease in global methylation level in Jurkat cells, at 6, 12, 24 and 48 hours （P < 0.01 or 0.05）. The mRNA expression of Gadd45a negatively correlated with the global level of DNA methylation in Jurkat cells （r = -0.395, P < 0.05）. Conclusion UVB irradiation can upregulate the expression of Gadd45a, but downregulate the global DNA methylation level in Jurkat cells.

Key words: 【Key words】 ultraviolet, Jurkat cells, Gadd45a, methylation