Abstract:
Spontaneous gain or loss of DNA methylation occurs in plant and animal genomes, and DNA methylation changes can lead to meiotically stable epialleles that generate heritable phenotypic diversity. However, it is unclear whether transgenerational epigenetic stability may be regulated by any cellular factors. Here, we examined spontaneously occurring variations in DNA methylation in wild-type and ros1 mutant Arabidopsis plants that were propagated for ten generations from single-seed descent. We found that the ros1 mutant, which is defective in active DNA demethylation, showed an increased transgenerational epimutation rate. The ros1 mutation led to more spontaneously gained methylation than lost methylation at individual cytosines, compared to the wild type which had similar numbers of spontaneously gained and lost methylation cytosines. Consistently, transgenerational differentially methylated regions were also biased toward hypermethylation in the ros1 mutant. Our results reveal a genetic contribution of the ROS1 DNA demethylase to transgenerational epigenetic stability and suggest that ROS1 may have an unexpected surveillance function in preventing transgenerational DNA methylation increases.
摘要:
自发获得或丢失的DNA甲基化发生在植物和动物基因组,和DNA甲基化变化可以导致产生可遗传表型多样性的减数分裂稳定的表观等位基因。然而,目前尚不清楚跨代表观遗传稳定性是否受任何细胞因子的调节.这里,我们检查了野生型和ros1突变拟南芥植物中自发发生的DNA甲基化变异,这些植物从单种子血统繁殖了十代。我们发现Ros1突变体,在活跃的DNA去甲基化中存在缺陷,表现出增加的跨代生殖率。在单个胞嘧啶中,ros1突变导致自发获得的甲基化比丢失的甲基化更多。与具有相似数量的自发获得和丢失甲基化胞嘧啶的野生型相比。始终如一,在ros1突变体中,跨代差异甲基化区域也偏向超甲基化.我们的结果揭示了ROS1DNA去甲基酶对跨代表观遗传稳定性的遗传贡献,并表明ROS1在防止跨代DNA甲基化增加方面可能具有意想不到的监测功能。