中文摘要：

DNA甲基化是指生物体在DNA甲基转移酶的催化下,以S-腺苷甲硫氨酸为甲基供体,将甲基转移到特定的碱基上的过程,是在不改变DNA分子一级结构的情况下对DNA序列进行的一种表观遗传修饰.在植物中,DNA甲基化在基因表达、细胞分化和生长发育过程中均发挥着重要的调节作用.概述了植物DNA甲基化的特征,并对DNA甲基化的机制、维持及其在植物中的生物学意义进行了讨论.

英文摘要：

DNA Methylation is a process that DNA methyltransferases catalyze the transfer of a methyl group to DNA using S-adenosyl methionine（SAM） as the methyl donor.It is an epigenetic modification with unchanged primary structure of DNA.DNA methylation plays an important role in the regulation of gene expression,cell differentiation,and growth and development in plants.This paper summarized the characteristics of DNA methylation,and discussed the mechanism,maintenance,and the biological significance of DNA methylation in plants.