Departamento de Biología Vegetal y Ecología, Universidad de Sevilla, Sevilla, Spain.
Department of Botany and Biodiversity Research, University of Vienna, Vienna, Austria.
Plant Biol (Stuttg). 2018 Jan;20 Suppl 1:38-49. doi: 10.1111/plb.12594. Epub 2017 Jul 12.
Epigenetic signals can affect plant phenotype and fitness and be stably inherited across multiple generations. Epigenetic regulation plays a key role in the mechanisms of plant response to the environment, without altering DNA sequence. As plants cannot adapt behaviourally or migrate instantly, such dynamic epigenetic responses may be particularly crucial for survival of plants within changing and challenging environments, such as the Mediterranean-Type Ecosystems (MTEs). These ecosystems suffer recurrent stressful events (warm and dry summers with associated fire regimes) that have selected for plants with similar phenotypic complex traits, resulting in similar vegetation growth forms. However, the potential role of epigenetics in plant adaptation to recurrent stressful environments such as the MTEs has generally been ignored. To understand the full spectrum of adaptive processes in such contexts, it is imperative to prompt study of the causes and consequences of epigenetic variation in natural populations. With this purpose, we review here current knowledge on epigenetic variation in natural populations and the genetic and epigenetic basis of some key traits for plants in the MTEs, namely those traits involved in adaptation to drought, fire and oligotrophic soils. We conclude there is still much to be learned about 'plant epigenetics in the wild' and, thus, we propose future research steps in the study of natural epigenetic variation of key traits in the MTEs at different scales.
表观遗传信号可以影响植物表型和适应性，并在多代中稳定遗传。表观遗传调控在植物对环境的反应机制中起着关键作用，而不会改变 DNA 序列。由于植物不能即时地改变行为或迁移，因此这种动态的表观遗传反应对于在不断变化和具有挑战性的环境中（如地中海型生态系统（MTEs））生存的植物可能特别重要。这些生态系统经常遭受反复的压力事件（温暖和干燥的夏季以及相关的火灾制度），这些压力事件选择了具有类似表型复杂特征的植物，导致类似的植被生长形式。然而，表观遗传学在植物适应反复出现的压力环境（如 MTEs）方面的潜在作用通常被忽视了。为了全面了解此类环境中的适应过程，必须及时研究自然种群中表观遗传变异的原因和后果。为此，我们在这里回顾了自然种群中表观遗传变异的现有知识，以及 MTEs 中一些关键植物性状的遗传和表观遗传基础，即那些与干旱、火灾和贫营养土壤适应有关的性状。我们得出的结论是，关于“野生植物表观遗传学”还有很多需要了解的地方，因此，我们提出了在不同尺度上研究 MTEs 中关键性状的自然表观遗传变异的未来研究步骤。
