School of Life Sciences, Yunnan University.
Institute of Ecology and Geobotany, School of Ecology and Environmental Sciences, Yunnan University.
Genes Genet Syst. 2021 Feb 11;95(5):225-234. doi: 10.1266/ggs.20-00025. Epub 2020 Nov 11.
Thlaspi arvense (field pennycress) is widespread in temperate regions of the northern hemisphere. We estimated the genetic and epigenetic structure of eight T. arvense populations (131 individuals) in China using amplified fragment length polymorphism and methylation-sensitive amplified polymorphism molecular-marker techniques. We detected low diversity at both genetic (mean = 0.03; total = 0.07) and epigenetic (mean = 0.04; total = 0.07) levels, while significant genetic (F = 0.42, P < 0.001) and epigenetic (F = 0.32, P < 0.001) divergence was found across the distribution range. Using Mantel testing, we found spatial genetic and epigenetic differentiation, consistent with isolation-by-distance models. We also identified a strong correlation between genetic and epigenetic differentiation (r = 0.7438, P < 0.001), suggesting genetic control of the epigenetic variation. Our results indicate that mating system, natural selection and gene flow events jointly structure spatial patterns of genetic and epigenetic variation. Moreover, epigenetic variation may serve as a basis of natural selection and ecological evolution to enable species to adapt to heterogeneous habitats. Our study provides novel clues for the adaptation of T. arvense.
野菘蓝（田芥菜）广泛分布于北半球温带地区。我们使用扩增片段长度多态性和甲基化敏感扩增多态性分子标记技术，对中国 8 个野菘蓝种群（131 个个体）的遗传和表观遗传结构进行了估计。我们在遗传水平（平均值为 0.03；总平均值为 0.07）和表观遗传水平（平均值为 0.04；总平均值为 0.07）都检测到了低多样性，而在整个分布范围内发现了显著的遗传（F = 0.42，P < 0.001）和表观遗传（F = 0.32，P < 0.001）分化。通过 Mantel 检验，我们发现了空间遗传和表观遗传分化，与隔离距离模型一致。我们还发现遗传分化和表观遗传分化之间存在很强的相关性（r = 0.7438，P < 0.001），表明遗传对表观遗传变异的控制。我们的研究结果表明，交配系统、自然选择和基因流事件共同构成了遗传和表观遗传变异的空间格局。此外，表观遗传变异可能作为自然选择和生态进化的基础，使物种能够适应异质生境。我们的研究为野菘蓝的适应提供了新的线索。
