Bender K, Blattner C, Knebel A, Iordanov M, Herrlich P, Rahmsdorf H J
Forschungzentrum Karlsruhe, Institut für Genetik, Germany.
J Photochem Photobiol B. 1997 Jan;37(1-2):1-17. doi: 10.1016/s1011-1344(96)07459-3.
Irradiation of cells with wavelength ultraviolet (UVA, B and C) induces the transcription of many genes. The program overlaps with that induced by oxidants and alkylating agents and has both protective and other functions. Genes transcribed in response to UV irradiation include genes encoding transcription factors, proteases and viral proteins. While the transcription factor encoding genes is initiated in minutes after UV irradiation (immediate response genes) and depends exclusively on performed proteins, the transcription of protease encoding occurs only many hours after UV irradiation. Transcription factors controlling the activity of immediate response genes are activated by protein kinases belonging to the group of proline directed protein kinases immediately after UV irradiation. Experimental evidence suggests that these kinases are activated in UV irradiated cells through pathways which are used by growth factors. In fact, the first cellular reaction detectable in UV irradiated cells is the phosphorylation of several growth factor receptors at tyrosine residues. This phosphorylation does not depend on UV induced DNA damage, but is due to an inhibition of the activity of tyrosine phosphatases. In contrast, for late cellular reactions to UV, an obligatory role of DNA damage in transcribed regions of the genome can be demonstrated. Thus, UV is absorbed by several target molecules relevant for cellular signaling, and it appears that numerous signal transduction pathways are stimulated. The combined action of these pathways establishes the genetic program that determines the fate of UV irradiated cells.
用紫外线（UVA、B和C）波长照射细胞会诱导许多基因的转录。该程序与由氧化剂和烷基化剂诱导的程序重叠，并且具有保护和其他功能。响应紫外线照射而转录的基因包括编码转录因子、蛋白酶和病毒蛋白的基因。虽然编码转录因子的基因在紫外线照射后几分钟内启动（即时反应基因），并且完全依赖于已有的蛋白质，但编码蛋白酶的转录仅在紫外线照射数小时后发生。控制即时反应基因活性的转录因子在紫外线照射后立即被属于脯氨酸定向蛋白激酶组的蛋白激酶激活。实验证据表明，这些激酶在紫外线照射的细胞中通过生长因子所使用的途径被激活。事实上，在紫外线照射的细胞中可检测到的第一个细胞反应是几种生长因子受体在酪氨酸残基处的磷酸化。这种磷酸化不依赖于紫外线诱导的DNA损伤，而是由于酪氨酸磷酸酶活性的抑制。相反，对于细胞对紫外线的晚期反应，可以证明基因组转录区域中DNA损伤的必不可少的作用。因此，紫外线被几种与细胞信号传导相关的靶分子吸收，并且似乎许多信号转导途径被刺激。这些途径的联合作用建立了决定紫外线照射细胞命运的遗传程序。
