遗传 ›› 2000, Vol. 22 ›› Issue (5): 305-308.
刘胜学;曹佳;安辉;周紫垣 LIU Sheng-xue;CAO Jia;AN Hui;ZHOU Zi-yuan
摘要: 为研究昆明山海棠(THH)的遗传毒性和药理作用,采用单细胞克隆培养,双向筛选计数,多重PCR扩增与电泳分析,研究了THH诱导HL-60细胞HPRT基因突变率及分子突变谱。发现随着染毒剂量的增加,细胞接种存活率逐渐下降,突变频率明显升高;THH诱发突变主要由缺失和点突变两部分组成(46.6%和53.4%),而自发突变几乎全是点突变(92.3%);HPRT基因突变位点在各个外显子的分布较集中于基因的3′末端,且外显子1缺失只出现于全基因缺失中,外显子7/8与9多表现为连锁缺失(71.4%)。结果提示,THH具有明确的诱导HPRT基因突变的作用,且诱发突变与自发突变的分子图谱不一样,这可能与其作用机制有关。上述发现有助于阐明THH遗传毒性作用机理。
Abstract:The genotoxicity and pharmacologic activity of a Chinese medicinal herb,Tripterygium hypoglaucum(Lévl) Hutch (THH),was investigated by methods of single cell clone culture,two-way screening count,multiplex PCR amplification and electrophoresis technique.THH showed clear cytotoxicity and mutagenesis in human promyelocytic leukemia (HL-60) cells.When doses were increased,cell plating efficiency reduced and mutation frequency increased.The analysis showed that the spectra of spontaneous and THH?induced mutants were different.46.6% of THH?induced genetic changes were deletions,whereas the majority of spontaneous mutants(92.3%)exhibited point mutations.Mapping of all intragenic deletion breakpoints showed a random distribution of breakpoints in 9 exons,but toward the 3′ end of the HPRT gene.Exon 1 deletion only appeared in total gene deletion,and exon 7/8 and 9 deletion often showed chain deletion(71.4%).