植物跨代效应的表观遗传机制研究

跨代效应，又称传代效应或代际效应，是亲代经历的环境影响后代性状和行为的现象，这一效应可以提高后代对环境的生态适应性，是生物适应快速变化环境的重要机制。近年来，表观遗传机制，如DNA甲基化等，被证实是跨代效应的重要分子基础。然而，研究生态适应的表观遗传分子机制极具挑战，因当前基因组水平的表征方法难以应用于多基因型的研究体系。针对这一挑战，申请人前期工作以拟南芥为材料，建立了包括多基因型、多环境和多世代的跨代效应实验体系，并初步建立了全基因组甲基化分析流程。本项目将开展方法学研究，建立适用于多基因型的研究方法，实现植物特有甲基化的精确测量；并以此方法系统表征跨代效应实验体系中甲基化变异的模式，揭示变异产生的驱动力；最后，结合性状和多组学研究，分析甲基化变异在性状和转录水平的效应，阐明跨代效应的分子机制。本项目将会推动表观基因组学在自然种群和生态研究中的应用，加深对生态适应机制的认识。

Transgenerational effects refer to the phenomena that parental experience change the behaviors and characters of offspring. Transgenerational effects can increase the resistance of offspring to stressful environments and have adaptive values, and thus are anticipated to be an important adaptive strategy under rapid climate changes. Recently years, studies show epigenetic mechanisms such as DNA methylation can underline the transgenerational effect. However, understanding the epigenetic mechanisms of transgenerational effects is challenging, owing to the methodological limitations. Previously, using the model plant species Arabidopsis thaliana, we have established a transgenerational experiment that includes multiple environments, genotypes, and generations. Furthermore, we have developed a genome-wide methylation analysis method that can be applied to studies on multiple genotypes. In this project, we will continue developing this method to achieve precise quantification genome-wide methylation on plant-specific methylation contexts. Then, we will apply this method to analyzing methylation patterns of the established transgenerational experiment systematically to understand factors driving methylation changes. Finally, we will evaluate to what extent methylation changes cause transcriptome and phenotypic changes and be regulated by DNA sequence variation, to reveal molecular mechanisms of transgenerational effects. This project will promote the application of epigenomics to plant ecological studies, and will further our understanding of the mechanisms of rapid adaptation under global changes.