Satta L, Augusti-Tocco G, Ceccarelli R, Esposito A, Fiore M, Paggi P, Poggesi I, Ricordy R, Scarsella G, Cundari E
Dipartimento di Energetica, Università La Sapienza, Rome, Italy.
Mutat Res. 1995 Aug;347(3-4):129-33. doi: 10.1016/0165-7992(95)00031-3.
Background radiation is likely to constitute one of the factors involved in biological evolution since radiations are able to affect biological processes. Therefore, it is possible to hypothesize that organisms are adapted to environmental background radiation and that this adaptation could increase their ability to respond to the harmful effects of ionizing radiations. In fact, adaptive responses to alkylating agents and to low doses of ionizing radiation have been found in many organisms. In order to test for effects of adaptation, cell susceptibility to treatments with high doses of radiomimetic chemical agents has been studied by growing them in a reduced environmental radiation background. The experiment has been performed by culturing yeast cells (Saccharomyces cerevisiae D7) in parallel in a standard background environment and in the underground Gran Sasso National Laboratory, with reduced environmental background radiation. After a conditioning period, yeast cells were exposed to recombinogenic doses of methyl methanesulfonate. The yeast cells grown in the Gran Sasso Laboratory showed a higher frequency of radiomimetic induced recombination as compared to those grown in the standard environment. This suggests that environmental radiation may act as a conditioning agent.
背景辐射可能是参与生物进化的因素之一，因为辐射能够影响生物过程。因此，可以假设生物体适应环境背景辐射，并且这种适应可能会增强它们应对电离辐射有害影响的能力。事实上，在许多生物体中都发现了对烷基化剂和低剂量电离辐射的适应性反应。为了测试适应的效果，通过在降低的环境辐射背景下培养细胞，研究了细胞对高剂量拟辐射化学剂处理的敏感性。该实验是通过在标准背景环境和地下大萨索国家实验室中平行培养酵母细胞（酿酒酵母D7）进行的，地下实验室的环境背景辐射较低。经过一个预处理期后，将酵母细胞暴露于致重组剂量的甲磺酸甲酯中。与在标准环境中生长的酵母细胞相比，在大萨索实验室中生长的酵母细胞显示出更高频率的拟辐射诱导重组。这表明环境辐射可能起到预处理剂的作用。
