Christianson M L, Chiscon M O
Environ Health Perspect. 1978 Dec;27:77-83. doi: 10.1289/ehp.782777.
Results of a pilot program show that suspension cultured polyhaploid Nicotiana tabacum cells can be used to bioassay the effects of mutagens. Reproducible survival curves with significant regression coefficients are obtained. Putative mutation conferring resistance to amino acid analogs is significantly more frequent after exposure to mutagens; in contrast, habituants, cytokinin-independent clones, are significantly less frequent (although the variance of clone size increases!). The maximum spontaneous mutation rate is estimated at 3 X 10(-8); the equilibrium frequency of habituant cells in an otherwise nonhabituated culture is estimated at 5 X 10(-7). An evaluation of the system suggests changes in several and further characterization of other of the parameters involved. The use of haploid tobacco as an in vivo mutagen screen is briefly described, as is the importance of similar in vivo diploid systems for discriminating between various kinds of mutational processes.
一项试点项目的结果表明，悬浮培养的多单倍体烟草细胞可用于生物测定诱变剂的效果。获得了具有显著回归系数的可重复生存曲线。暴露于诱变剂后，赋予对氨基酸类似物抗性的推定突变明显更为频繁；相比之下，习惯型细胞（即不依赖细胞分裂素的克隆）则明显较少见（尽管克隆大小的方差增加了！）。最大自发突变率估计为3×10^(-8)；在原本非习惯型的培养物中，习惯型细胞的平衡频率估计为5×10^(-7)。对该系统的评估表明，涉及的几个参数发生了变化，其他参数需要进一步表征。简要描述了使用单倍体烟草作为体内诱变筛选的方法，以及类似的体内二倍体系统对于区分各种突变过程的重要性。
