No consistent daily variation in DNA methylation detected in Populus nigra leaves by methylation-sensitive amplification polymorphism analysis

作     者：Shu Diao Yanbo Wang Changjun Ding Yingying Chang Lixiong Liang Yanan Gao Bingyu Zhang Xiaohua Su 

作者机构：State Key Laboratory of Tree Genetics and BreedingResearch Institute of ForestryChinese Academy of ForestryBeijing 100091People’s Republic of China Key Laboratory of Tree Breeding and Cultivation of State Forestry AdministrationResearch Institute of ForestryChinese Academy of ForestryBeijing 100091People’s Republic of China 

出 版 物：《Journal of Forestry Research》 (林业研究（英文版）)

年 卷 期：2017年第28卷第4期

页      面：653-660页

核心收录：

学科分类：0907[农学-林学] 08[工学] 0829[工学-林业工程] 09[农学] 

基　　金：supported by National Nonprofit Institute Research Grant of Chinese Academy of Forestry(TGB2013010) 

主　　题：Cytosine methylation Epigenetic Populus nigra Methylation-sensitive amplification polymorphism (MSAP) Variation 

摘      要：DNA methylation, an epigenetic mechanism used by cells to control gene expression, has an important biological role in plant development and environmental fitness. Since plant DNA methylation is closely related to environmental conditions, variation during the day is expected. Here, in genetically identical plants of Populus nigra clone N46, DNA methylation changes in leaves over a 24 h period were detected using the methylation-sensitive amplification polymorphism method. The results showed different DNA methylation patterns in mature poplar leaves: not only in individuals at the same time, but also in samples at each of the six time during the day. In addition, night samples had a higher percentage of methylation than in morning samples. However, no statistically significant differences were found among the samples gathered at different times. Similar results were obtained for three other P. nigra clones with different genetic backgrounds. Real time qPCR showed that the DNA methyltransferase genes Pt-MET1 and Pt-SOM1 involved in CG DNA methylation in poplar were stable over a 24 h period in leaves of P. nigra N46 compared with circadian-controlled genes. That could be part of the reason that methylation of CCGG sites is stable in those leaves. That DNA methylation differed even in genetically identical plants indicates the specificity of DNA methylation changes in their genomes. No statistically significant differences in methylation changes were found between day and night, suggesting that DNA methylation is more stable than expected and is unlikely to be involved in circadian regulation in plants.