Vaĭserman A M, Litoshenko A Ia, Kvitnitskaia-Ryzhova T Iu, Koshel' N M, Mozzhukhina T G, Mikhal'skiĭ S A, Voĭtenko V P
Tsitol Genet. 2003 May-Jun;37(3):41-8.
The long-term effects of the R-irradiation of D. melanogaster at the 1-hour egg stage with the dosages of 0.25, 0.50, 0.75, 1.0, 2.0 and 4.0 Gy were investigated. DNA samples were isolated from whole 5-6-days adult males. The aliquots of DNA were digested by S1-nuclease. Preimaginal stage lethality increased with irradiation dose increasing. At the same time, decrease in imaginal LS (life span) was observed after irradiation with the greatest dose (4 Gy) only. Moreover, hormesis by LS has revealed: in males irradiation with 0.25, 0.75 and 1 Gy increased the mean LS, and with 0.25 and 0.5 Gy caused the maximum LS; in females exposures with 0.25, 0.75 and 2 Gy increased the maximum LS. The densitometric assay of DNA electrophoregrams showed decrease by 39.2% of the part of high-molecular-weight DNA in control as a result of S1-nuclease action. Samples of DNA from the irradiated flies were more stable to enzyme action. The higher stability of DNA originated from the irradiated flies could be the result of reparation system activation. Ultrastructural changes induced at the egg stage by irradiation at the dose of 0.75 Gy testify the increased transcriptional activity of the brain cells.
研究了用0.25、0.50、0.75、1.0、2.0和4.0戈瑞剂量对黑腹果蝇1小时卵期进行R射线照射的长期影响。从5至6日龄的成年雄蝇整体中分离DNA样本。DNA等分试样用S1核酸酶消化。幼虫前期致死率随照射剂量增加而升高。同时，仅在接受最大剂量（4戈瑞）照射后观察到成虫寿命缩短。此外，还发现了寿命的兴奋效应：在雄蝇中，0.25、0.75和1戈瑞的照射增加了平均寿命，0.25和0.5戈瑞的照射使寿命最长；在雌蝇中，0.25、0.75和2戈瑞的照射增加了最长寿命。DNA电泳图的光密度分析显示，由于S1核酸酶的作用，对照中高分子量DNA部分减少了39.2%。来自受照射果蝇的DNA样本对酶的作用更稳定。受照射果蝇的DNA具有更高的稳定性可能是修复系统激活的结果。0.75戈瑞剂量照射在卵期诱导的超微结构变化证明了脑细胞转录活性的增加。
