Damage to grass shrimp (Palaemonetes pugio) embryo DNA by summer sunlight followed by DNA repair in the dark
Damage to grass shrimp (Palaemonetes pugio) embryo DNA by summer sunlight followed by DNA repair in the dark
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夏季阳光对草虾 (Palaemonetes pugio) 胚胎 DNA 的损伤，随后在黑暗中进行 DNA 修复
DOI：
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发表时间：
2000
期刊：
影响因子：
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通讯作者：
D. Mitchell
中科院分区：
文献类型：
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作者：
G. B. Kim;R. Lee;D. Mitchell
用单细胞凝胶电泳法测定了采自美国佐治亚州萨凡纳附近河口的草虾不同发育阶段胚胎的 DNA链损伤。夏季中午从河口采集的晚期胚胎或放置在太阳模拟器中的胚胎显示出广泛的DNA链损伤。太阳模拟器产生的总辐射相当于夏季中午34°N的总辐射，对胚胎的DNA链损伤与阳光照射下的胚胎相似。在日照照度为12 6 μW cm−2的条件下，晚期胚胎DNA中的环丁烷嘧啶二聚体大量增加(每1000个碱基18个环丁烷嘧啶二聚体)。当中午从河里采集的晚期胚胎被转移到黑暗中时，DNA修复在几个小时内进行了。无论是放置在太阳模拟器中还是在夏季中午收集，早期草虾胚胎阶段都没有显示出DNA链损伤。早期胚胎中缺乏受到太阳损伤的DNA，可能是因为存在高浓度的类胡萝卜素，类胡萝卜素可以作为抗氧化剂，防止暴露在紫外线下的细胞产生的活性氧物种造成的损害。这些类胡萝卜素被发育中的胚胎利用，在胚胎后期只有低浓度的类胡萝卜素存在。
Abstract DNA strand damage, using the single-cell gel electrophoresis (comet) method, was determined in different-stage embryos of grass shrimp (Palaemonetes pugio) collected from surface waters of a local estuary near Savannah, Georgia, USA. Late-stage embryos collected from the estuarine river at midday in the summer or placed in a solar simulator showed extensive DNA strand damage. The solar simulator, which produced the total irradiance found at midday in the summer at 34°N caused DNA strand damage in embryos similar to that found in sunlight-exposed embryos. A large increase in cyclobutane pyrimidine dimers (18 cyclobutane pyrimidine dimers per 1000 kilobases) were detected in DNA from the late-stage embryos exposed to the solar simulator for 1 h (solar irradiance of 126 μW cm−2). DNA repair took place within a few hours when late-stage embryos collected at midday from the river were transferred to the dark. Early grass-shrimp embryo stages showed no DNA strand damage either after placement in the solar simulator or when collected at midday in the summer. This lack of solar-damaged DNA in early-stage embryos was probably due to the presence of high concentrations of carotenoids, which can act as anti-oxidants to prevent damage from activated oxygen species produced by cells exposed to ultraviolet light. These carotenoids are utilized by the developing embryos, and only low concentrations of carotenoids were present in late embryo stages.