[关键词]
[摘要]
DNA甲基化是目前研究最为广泛的一种表观遗传学现象,甲基化后的DNA可在不改变碱基序列的情况下对植物的表型进行调控。在高等植物中有CG、CHG和CHH(H代表A、C或T)3种甲基化位点,多发生于对称序列CG和重复序列中,且不同物种中的甲基化程度和模式不同。药用植物功能基因启动子区域的DNA发生甲基化后,可抑制基因的表达,进而影响其次生代谢产物的积累,导致品质差异的形成。在众多的DNA甲基化检测方法中,重亚硫酸盐测序法可在单核苷酸水平上鉴别DNA甲基化的位点和程度,是DNA甲基化分析的金标准。对其进行引物优化、技术改良后,可有效地揭示药用植物的DNA甲基化情况,这为阐明经典遗传学不能完全解释的药用植物品质差异等问题提供了技术支持,并开辟了新的研究方向。
[Key word]
[Abstract]
DNA methylation is one of the most widely epigenetics phenomena, methylated DNA can regulate the phenotype of plants without changing the nucleotide sequence. In higher plants, there are three methylated sites, CG, CHG, and CHH (H stands for A, C, or T). They often occur in symmetrical sequences CG and repetitive sequence, and methylation degrees and patterns are different among different species. The methylation of functional gene promoters can suppress the gene expression in medicinal plants, and then affect the accumulation of secondary metabolites, resulting in quality variations. Among many methods for the DNA methylation detection, bisulfite sequencing can identify the site and extent of DNA methylation at single nucleotide level, which is the gold standard for DNA methylation analysis. Through optimizing primers and improving technology, it can effectively reveal the DNA methylation status for medicinal plants and provide technical support and a new research direction for clarifying some problems such as quality variations in medicinal plants, which are not completely explained by classical genetics.
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[基金项目]
国家自然科学基金资助项目(31570683);华北理工大学培育基金(SP201508)