Extreme tolerance and developmental buffering of UV-C induced DNA damage in embryos of the annual killifish Austrofundulus limnaeus.
Extreme tolerance and developmental buffering of UV-C induced DNA damage in embryos of the annual killifish Austrofundulus limnaeus.
复制标题
一年生鳉鱼 Austrofundulus limnaeus 胚胎中对 UV-C 诱导的 DNA 损伤的极端耐受性和发育缓冲。
DOI：
10.1002/jez.1890
复制
发表时间：
2015
期刊：
影响因子：
--
通讯作者：
Podrabsky,JasonE
中科院分区：
文献类型：
--
作者：
Wagner,JosiahT;Podrabsky,JasonE
自由生活的水生胚胎经常面临暴露于紫外线辐射（UV - R）的风险。胚胎发育的成功完成取决于DNA损伤的有效去除，因此许多水生胚胎具有逆转UV - R诱导的DNA损伤的机制。然而，对于能够进入胚胎休眠的胚胎如何对UV - R暴露和随后的DNA损伤做出反应，我们知之甚少。一年生鳉的胚胎在脊椎动物中是独一无二的，因为它们的正常胚胎发育包括：(1)胚胎卵裂球在最终胚胎轴形成之前完全分散，以及(2)进入称为滞育的代谢抑制和发育停滞状态。在这里，我们展示了a的发育和滞育胚胎。limnah对UV - C辐射具有特殊的耐受性，在接受大剂量的UV - C照射后，能够成功完成胚胎发育，特别是在全光谱下恢复。全光谱光恢复允许有效去除由UV - R诱导的最常见类型的DNA损伤：环丁烷嘧啶二聚体。有趣的是，全胚TUNEL试验表明，细胞凋亡可能不是分散/再聚集或滞育期间UV - C照射下胚胎细胞死亡的主要原因。我们还观察到，在绝育胚胎辐照后，在黑暗中恢复，胚胎死亡率明显推迟了几周。这些对UV - R诱导的DNA损伤的非典型反应可能是由于鳉鱼独特的生活史，并提供了胚胎休眠期间DNA损伤修复和识别机制的见解。实验与实验，2015,32(1):10-30。©2014 Wiley期刊公司
Free‐living aquatic embryos are often at risk of exposure to ultraviolet radiation (UV‐R). Successful completion of embryonic development depends on efficient removal of DNA lesions, and thus many aquatic embryos have mechanisms to reverse DNA lesions induced by UV‐R. However, little is known of how embryos that are able to enter embryonic dormancy may respond to UV‐R exposure and subsequent DNA damage. Embryos of the annual killifishAustrofundulus limnaeusare unique among vertebrates because their normal embryonic development includes (1) a complete dispersion of embryonic blastomeres prior to formation of the definitive embryonic axis, and (2) entry into a state of metabolic depression and developmental arrest termed diapause. Here, we show that developing and diapausing embryos ofA. limnaeushave exceptional tolerance of UV‐C radiation and can successfully complete embryonic development after receiving substantial doses of UV‐C, especially if allowed to recover in full‐spectrum light. Recovery in full‐spectrum light permits efficient removal of the most common type of DNA lesion induced by UV‐R: cyclobutane pyrimidine dimers. Interestingly, whole‐mount embryo TUNEL assays suggest that apoptosis may not be a major contributor to cell death in embryos UV‐C irradiated during dispersion/reaggregation or diapause. We also observed embryo mortality to be significantly delayed by several weeks in diapausing embryos irradiated and allowed to recover in the dark. These atypical responses to UV‐R induced DNA damage may be due to the unique annual killifish life history and provide insight into DNA damage repair and recognition mechanisms during embryonic dormancy.J. Exp. Zool. 323A: 10–30, 2015. © 2014 Wiley Periodicals, Inc.