中文摘要：

目的：探讨IκB激酶（IκB kinase，IKK）催化亚基α（IKKα）在紫外线（ultraviolet radiation， UV）诱导的细胞反应中介导p53活化的信号转导机制。方法采用双荧光素酶报告基因分析系统检测在UVB诱导细胞反应中p53的转录激活活性。 Western印迹检测IKKα、p53、p38K蛋白表达水平和诱导活化状态。结果 UVB在野生型小鼠成纤维细胞中能显著诱导p53发生磷酸化修饰反应；同时转录激活活性显著提高，IKKα基因敲除后，以上活化反应受到显著抑制，而恢复IKKα表达水平后这种活化反应得以恢复。同样条件下IKKα也能调节p38K的诱导活化，抑制p38K活性显著下调p53的诱导活化水平。结论 IKKα能通过调控p38K活化进而介导UVB诱导p53磷酸化修饰反应。

英文摘要：

Objective To explore the signal transduction mechanism of inhibitor kappa B kinase α（ IKKα） , one of the catalytic subunits of IKK complex , for regulating p53 transactivation in the cellular ultraviolet radiation （ UVB） repsonse. Methods The transactivation of p53 was determined by dual-luciferase reporter gene analysis system while the expression and activation of IKKα, IKKβ, p53 and p38K was detected by Western blotting assay .Results UVB exposure induced activation and transactivation of p 53 in the wild type mouse fibroblasts ,but the effect was blocked by IKKa deficiency and recovered by reconstitution of IKKαexpression.Under the same conditions , IKKαregulated p38K activation, while inhibi-ting p38K activation down-regulated p53 transactivation under UVB exposure .Conclusion IKKαregulates UVB-induced phosphorylation and activation of p 53 in a p38K-dependent manner .