湿地松×洪都拉斯加勒比松及亲本DNA胞嘧啶甲基化的初步研究

Study on genomic DNA cytosine methylation of Pinus elliottii var. elliottii × P. caribaea var. hondurensis and their parents

以湿地松×洪都拉斯加勒比松(Pinus elliottii×P.caribaea var.hondurensis)及亲本为实验材料,采用甲基化敏感扩增多态性技术对其基因组中CCGG位点的甲基化相对水平及遗传变异模式进行了初步分析。结果表明,杂种及亲本CCGG总甲基化相对水平介于77.74%~81.75%,CG甲基化相对水平略低于CNG甲基化水平,CG/CNG甲基化相对水平高于亲本。杂种遗传自亲本的CG与CNG甲基化位点数之比接近1∶1,遗传自母本的甲基化位点数与遗传自父本的CCGG甲基化位点数比例为1∶1;杂种产生的全新甲基化与完全去甲基化位点数之比接近7∶1,初步推测大量甲基化变异促进了杂合体的生长发育。

We investigated aspects of epigenetic regulation to reveal the genetic variation of Pinus elliottii x P. caribaea var. hondurensis. We analyzed the cytosine methylation patterns in P. elliottii x P. caribaea var. hondurensis hybrids and their parents using the MSAP method, and comparatively examined the methylation types and differences between the hybrids and their parents. Our results showed that the relative levels of methylation in the parent and hybrid CCGG were 77.74% - 81.75%. The relative level of CG methylation was lower than the relative level of CNG methylation. The relative level of CG/CNG methylation was higher than that in the parents. There was a 1：1 ratio between heredity in hybrid. CG and CNG methylation sites inherited from parents were equal, as were the methylation sites inherited from the female and male parents. The ratio of new methylation to complete demethylation sites was close to 7：1 in the hybrids. This study infers that methylation mutation promoted the growth and development of the heterozygotes.