Elevated UV-B radiation reduces genome stability in plants
Elevated UV-B radiation reduces genome stability in plants
复制标题
DOI：
10.1038/35017595
复制
发表时间：
2000-07-06
期刊：
影响因子：
64.8
通讯作者：
Hohn, B
中科院分区：
文献类型：
--
作者：
Ries, G;Heller, W;Hohn, B
平流层臭氧层的长期消耗导致地球太阳紫外线-B辐射的增加（1-3）。这对生物体有有害影响，如DNA损伤（4，5）。当暴露于紫外线B辐射（UV-B; 280-315 nm）时，植物表现出各种各样的生理和形态反应，其特征在于驯化和适应（6）。在这里，我们表明，使用特殊的太阳模拟器，太阳UV-B剂量升高增加拟南芥和烟草植物体细胞同源DNA重排的频率。重组的增加伴随着光裂合酶和Rad 51基因表达的强烈诱导。这些基因参与主要的DNA修复途径、光复活和重组修复（7，8）。在突变的拟南芥植物是缺乏光活化紫外线诱导的环丁烷嘧啶二聚体，在升高的UV-B制度下的重组大大超过野生型水平。我们的研究结果表明，同源重组修复途径可能参与消除UV-B诱导的植物DNA损伤。因此，地球太阳紫外线B辐射的增加，如预测的21世纪初世纪可能影响植物基因组的稳定性。
Long-term depletion of the stratospheric ozone layer contributes to an increase in terrestrial solar ultraviolet-B radiation(1-3). This has deleterious effects on living organisms, such as DNA damage(4,5). When exposed to elevated ultraviolet-B radiation (UV-B; 280-315 nm), plants display a wide variety of physiological and morphological responses characterized as acclimation and adaptation(6). Here we show, using special sun simulators, that elevated solar UV-B doses increase the frequency of somatic homologous DNA rearrangements in Arabidopsis and tobacco plants. Increases in recombination are accompanied by a strong induction of photolyase and Rad51 gene expression. These genes are putatively involved in major DNA repair pathways, photoreactivation and recombination repair(7,8). In mutant Arabidopsis plants that are deficient in photoreactivating ultraviolet-induced cyclobutane pyrimidine dimers, recombination under elevated UV-B regimes greatly exceeds wild-type levels. Our results show that homologous recombination repair pathways might be involved in eliminating UV-B-induced DNA lesions in plants. Thus, increases in terrestrial solar UV-B radiation as forecasted for the early 21st century may affect genome stability in plants.