Yang H P, Tanikawa A Y, Van Voorhies W A, Silva J C, Kondrashov A S
Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, New York 14853, USA.
Genetics. 2001 Mar;157(3):1257-65. doi: 10.1093/genetics/157.3.1257.
We induced mutations in Drosophila melanogaster males by treating them with 21.2 mm ethyl methanesulfonate (EMS). Nine quantitative traits (developmental time, viability, fecundity, longevity, metabolic rate, motility, body weight, and abdominal and sternopleural bristle numbers) were measured in outbred heterozygous F3 (viability) or F2 (all other traits) offspring from the treated males. The mean values of the first four traits, which are all directly related to the life history, were substantially affected by EMS mutagenesis: the developmental time increased while viability, fecundity, and longevity declined. In contrast, the mean values of the other five traits were not significantly affected. Rates of recessive X-linked lethals and of recessive mutations at several loci affecting eye color imply that our EMS treatment was equivalent to approximately 100 generations of spontaneous mutation. If so, our data imply that one generation of spontaneous mutation increases the developmental time by 0.09% at 20 degrees and by 0.04% at 25 degrees, and reduces viability under harsh conditions, fecundity, and longevity by 1.35, 0.21, and 0.08%, respectively. Comparison of flies with none, one, and two grandfathers (or greatgrandfathers, in the case of viability) treated with EMS did not reveal any significant epistasis among the induced mutations.
我们通过用21.2毫米甲磺酸乙酯（EMS）处理黑腹果蝇雄性来诱导突变。在经处理雄性的远交杂合F3（活力）或F2（所有其他性状）后代中测量了九个数量性状（发育时间、活力、繁殖力、寿命、代谢率、运动能力、体重以及腹部和胸骨侧刚毛数量）。前四个与生活史直接相关的性状的平均值受到EMS诱变的显著影响：发育时间增加，而活力、繁殖力和寿命下降。相比之下，其他五个性状的平均值没有受到显著影响。隐性X连锁致死率以及几个影响眼色的位点的隐性突变率表明，我们的EMS处理相当于大约100代的自发突变。如果是这样，我们的数据表明，一代自发突变在20摄氏度时使发育时间增加0.09%，在25摄氏度时增加0.04%，并分别使恶劣条件下的活力、繁殖力和寿命降低1.35%、0.21%和0.08%。对未经处理、有一个和有两个用EMS处理的祖父（或在活力方面为曾祖父）的果蝇进行比较，未发现诱导突变之间存在任何显著的上位性。
