Induction of p21 mRNA synthesis after short-wavelength UV light visualized in individual cells by RNA FISH
Induction of p21 mRNA synthesis after short-wavelength UV light visualized in individual cells by RNA FISH
复制标题
DOI：
10.1177/002215540205000109
复制
发表时间：
2002-01-01
影响因子：
3.2
通讯作者：
Dirks, RW
中科院分区：
文献类型：
--
作者：
Hattinger, CM;Jochemsen, AG;Dirks, RW
细胞周期蛋白依赖性激酶抑制剂基因p21的表达在DNA损伤后被诱导，并在细胞存活中起作用。诱导的确切机制尚不清楚，但最近已发现mRNA稳定性的增强是一个重要因素。为了进一步了解p21基因表达在单个细胞水平的动态，正常成纤维细胞，GM1492成纤维细胞从布卢姆氏综合征患者，和U2OS骨肉瘤细胞的紫外线照射，固定在不同的时间点，并进行mRNA荧光原位杂交（FISH）和免疫细胞化学染色。在模拟照射的正常成纤维细胞，一个亚组的细胞显示低水平的p21 mRNA的合成。UVC治疗后，随着时间的推移，p21的转录积累在核位置以外的转录灶。照射后6小时，几乎50%的细胞显示p21 mRNA在核内的三种不同的分布模式。UVC处理后17小时，细胞内p21 mRNA积累的频率最高。我们的结论是，增加p21基因转录和可能的稳定新合成的p21 mRNA有助于p21蛋白水平升高UVC照射后。
Expression of the cyclin-dependent kinase inhibitor gene p21 is induced after DNA damage and plays a role in cell survival. The exact mechanism of induction is not known, but enhancement of mRNA stability has recently been implicated as an important factor. To obtain further insight into the dynamics of p21 gene expression at the individual cell level, normal fibroblasts, GM1492 fibroblasts from a Bloom's syndrome patient, and U2OS osteosarcoma cells were UVC irradiated, fixed at different time points, and subjected to mRNA fluorescence in situ hybridization (FISH) and immunocytochemical staining. In mock-irradiated normal fibroblasts, a subfraction of cells revealed low levels of p21 mRNA synthesis. After UVC treatment, p21 transcripts accumulated over time in nuclear locations other than transcription foci. At 6 hr after irradiation, almost 50% of the cells displayed p21 mRNA in three different distribution patterns within the nuclei. The highest frequency of cells with cytoplasmic accumulation of p21 mRNA was seen at 17 hr after UVC treatment. We conclude that increased p21 gene transcription and possibly stabilization of newly synthesized p21 mRNA contribute to elevated levels of p21 protein after UVC irradiation.