不同浓度镉胁迫对孔雀草DNA甲基化的影响

随着人类活动、工业化发展进程的加快,重金属污染对环境造成了严重危害。本研究通过盆栽试验,利用甲基化敏感扩增多态性(MSAP)技术,对不同浓度镉(Cd)胁迫下孔雀草(Tagetes patula)基因组DNA甲基化变化情况进行了分析研究。结果表明,经0、50、250和500mg·kg-1浓度Cd~(2+)处理后,基因组MSAP比率分别为24%、30%、35%和41%,全甲基化率分别为20%、23%、25%和27%,这表明重金属胁迫处理后,DNA总甲基化水平随Cd~(2+)浓度升高而呈上升趋势;在DNA甲基化模式变化方面,50、250和500 mg·kg-1浓度胁迫下重新甲基化率分别为10%、10%和11%,重新甲基化为主要的甲基化变化模式。本研究可以为揭示重金属胁迫对植物DNA甲基化变化规律及植物对重金属胁迫耐受性机制提供理论参考。

Effects of different concentrations Cd stress on DNA methylation of Tagetes patula

With the speeding up of human’s activity and industrialization process,heavy metal pollution has caused serious harm to the environment.In the present study,the methylation-sensitive amplified polymor-phism (MSAP)technique was employed to analyze the DNA methylation in Tagetes patula under different concentrations of cadmium (Cd)in pots experiment.The results showed that the genomic MSAP rate of T.patula was 24%,30%,35% and 41%,and the total methylation rate of T.patula was 20%,23%,25%and 27%,respectively,when treated with the different concetrations of Cd2+(0,50,250,500 mg?kg-1 ).The results indicated that the total methylation level of DNA increased with the increase of Cd2+ concentration.Mo-reover,in regards of the change pattern of DNA methylation,the denove methylation rates were 10%,10%and 11%,respectively,under stress of 50,250 and 500 mg?kg-1 Cd2+,which indicated that the denove meth-ylation was the main methylation pattern.In summay,the current study provides a theoretical reference for re-vealing the variation trend of heavy metal stress on plant DNA methylation and the mechanism of plant toler-ance to heavy metal stress.