Department of Biological Sciences, University of Lethbridge Lethbridge, AB, Canada.
Front Genet. 2013 Apr 4;4:40. doi: 10.3389/fgene.2013.00040. eCollection 2013.
The number of people that receive exposure to ionizing radiation (IR) via occupational, diagnostic, or treatment-related modalities is progressively rising. It is now accepted that the negative consequences of radiation exposure are not isolated to exposed cells or individuals. Exposure to IR can induce genome instability in the germline, and is further associated with transgenerational genomic instability in the offspring of exposed males. The exact molecular mechanisms of transgenerational genome instability have yet to be elucidated, although there is support for it being an epigenetically induced phenomenon. This review is centered on the long-term biological effects associated with IR exposure, mainly focusing on the epigenetic mechanisms (DNA methylation and small RNAs) involved in the molecular etiology of IR-induced genome instability, bystander and transgenerational effects. Here, we present evidence that IR-mediated effects are maintained by epigenetic mechanisms, and demonstrate how a novel, male germline-specific, small RNA pathway is posited to play a major role in the epigenetic inheritance of genome instability.
接触电离辐射（IR）的人数通过职业、诊断或治疗相关的方式逐渐增加。现在人们已经接受了这样一种观点，即辐射暴露的负面影响并不仅限于暴露的细胞或个体。IR 暴露可导致生殖细胞中的基因组不稳定性，并且进一步与暴露雄性的后代中的跨代基因组不稳定性相关联。尽管有证据支持它是一种表观遗传诱导现象，但跨代基因组不稳定性的确切分子机制仍有待阐明。本篇综述主要集中于与 IR 暴露相关的长期生物学效应，重点讨论了参与 IR 诱导的基因组不稳定性、旁观者和跨代效应的分子病因学的表观遗传机制（DNA 甲基化和小 RNA）。在这里，我们提出了 IR 介导的效应是由表观遗传机制维持的证据，并展示了一种新的、雄性生殖细胞特异性的小 RNA 途径如何在基因组不稳定性的表观遗传遗传中发挥主要作用。
