Parental DNA Methylation States Are Associated with Heterosis in Epigenetic Hybrids

作者：Kathrin Lauss, René Wardenaar, Rurika Oka, M.H.A. van Hulten, Victor Guryev, Joost J. B. Keurentjes, Maike Stam, Frank Johannes · 发表于：PLANT PHYSIOLOGY · 年份：2017 · DOI：10.1104/pp.17.01054 · 被引用次数：136 · 研究领域：Genetic Mapping and Diversity in Plants and Animals、Plant Molecular Biology Research、Soybean genetics and cultivation

Despite the importance and wide exploitation of heterosis in commercial crop breeding, the molecular mechanisms behind this phenomenon are not completely understood. Recent studies have implicated changes in DNA methylation and small RNAs in hybrid performance; however, it remains unclear whether epigenetic changes are a cause or a consequence of heterosis. Here, we analyze a large panel of over 500 Arabidopsis (Arabidopsis thaliana) epigenetic hybrid plants (epiHybrids), which we derived from near-isogenic but epigenetically divergent parents. This proof-of-principle experimental system allowed us to quantify the contribution of parental methylation differences to heterosis. We measured traits such as leaf area, growth rate, flowering time, main stem branching, rosette branching, and final plant height and observed several strong positive and negative heterotic phenotypes among the epiHybrids. Using an epigenetic quantitative trait locus mapping approach, we were able to identify specific differentially methylated regions in the parental genomes that are associated with hybrid performance. Sequencing of methylomes, transcriptomes, and genomes of selected parent-epiHybrid combinations further showed that these parental differentially methylated regions most likely mediate the remodeling of methylation and transcriptional states at specific loci in the hybrids. Taken together, our data suggest that locus-specific epigenetic divergence between the parental lines can directly or...