重金属铬对小麦根系DNA甲基化水平的影响

Effects of Heavy Metal Chromium on the DNA Methylation in Roots of Wheat Seedlings

采用紫外分光光度法和高效液相色谱法对不同浓度Cr6+对小麦幼苗根系的DNA含量和DNA胞嘧啶甲基化进行了研究。结果表明:(1)Cr6+导致小麦幼苗根系DNA含量显著降低,3 d龄幼苗根系DNA含量下降的幅度大于10 d龄幼苗。(2)5～80mg.L-1和5～100mg.L-1Cr6+依次引发了3 d和10 d龄小麦幼苗根系DNA胞嘧啶甲基化水平的提高,而100mg.L-1Cr6+则导致了3d龄幼苗根系DNA胞嘧啶甲基化水平的降低。说明Cr6+可通过影响小麦幼苗根系DNA甲基化的水平,进而影响小麦的正常生长发育。

The effects of Cr6＋ on the DNA contents and DNA methylation in roots of wheat seedlings were studied.The results indicated that：（1） DNA contents in roots of seedlings were all markedly reduced by Cr6＋,and the declining extent of DNA content in roots of 3-day-old seedlings was bigger than that of 10-day-old seedlings.（2） The 5-MeC content in the roots DNA of 3-day-old seedlings with 5-100 mg·L-1Cr6＋ treatment were higher than that of control seedlings.But in the roots DNA of 3-day-old seedlings,exception that the 5-MeC content with 100 mg·L-1Cr6＋ treatment was lower than that of control seedlings,5-MeC contents with the 5-80 mg·L-1Cr6＋ tested concentrations were still higher than that of control seedlings.Cr6＋ can affect DNA methylation level in wheat seedling roots,thereby affecting the normal growth and development of wheat.