PNAS:福建农大王海峰研究组发表挪威云杉甲基化组研究成果论文
2016年12月6日,国际著名学术期刊《美国国家科学院院刊》杂志在线发表了福建农林大学海峡联合研究院林学中心王海峰研究组和美国加州大学史蒂夫·杰克布森教授研究组合作的题为“DNA methylome of the 20-gigabase Norway spruce genome”研究论文。该研究是我校在国际高水平期刊发表的有关林学领域研究的重要成果之一。以色列·奥辛老师为第一作者，史蒂夫·杰克布森教授和王海峰老师为论文共同通讯作者。
植物表观遗传学是当今研究的热点之一。DNA甲基化是表观遗传学领域研究的重点，在许多生物学过程中发挥重要作用，其功能如调控基因表达等在被子植物中被广泛报道。然而，在裸子植物中，DNA甲基化的作用和模式还不清楚。本研究以树木挪威云杉为模式，绘制了挪威云杉松针和体胚细胞的全基因组高覆盖度的单碱基甲基化图谱。揭示了挪威云杉CG和CHG的甲基化水平比大多数植物更高;但CHH的甲基化水平较低，并与siRNAs的水平呈共相关性。RNA介导的 DNA甲基化途径的大部分基因在挪威云杉中至少存在一个拷贝。此外，与松针相比，用于无性繁殖杉木的体胚细胞中CG 和CHG 的甲基化水平较低，而CHH的甲基化水平较高，这表明了体胚细胞中甲基化模式存在异常。
图挪威云杉松针和体胚细胞中DNA甲基化差异比较
原文链接：
DNA methylome of the 20-gigabase Norway spruce genome
原文摘要：
DNA methylation plays important roles in many biological processes, such as silencing of transposable elements, imprinting, and regulating gene expression. Many studies of DNA methylation have shown its essential roles in angiosperms (flowering plants). However, few studies have examined the roles and patterns of DNA methylation in gymnosperms. Here, we present genome-wide high coverage single-base resolution methylation maps of Norway spruce (Picea abies) from both needles and somatic embryogenesis culture cells via whole genome bisulfite sequencing. On average, DNA methylation levels of CG and CHG of Norway spruce were higher than most other plants studied. CHH methylation was found at a relatively low level; however, at least one copy of most of the RNA-directed DNA methylation pathway genes was found in Norway spruce, and CHH methylation was correlated with levels of siRNAs. In comparison with needles, somatic embryogenesis culture cells that are used for clonally propagating spruce trees showed lower levels of CG and CHG methylation but higher level of CHH methylation, suggesting that like in other species, these culture cells show abnormal methylation patterns.
作者：王海峰
