Bräutigam Katharina, Cronk Quentin
Department of Biology, University of Toronto Mississauga, Mississauga, ON, Canada.
Department of Botany, The University of British Columbia, Vancouver, BC, Canada.
Front Plant Sci. 2018 Oct 4;9:1447. doi: 10.3389/fpls.2018.01447. eCollection 2018.
All land plants so far examined use DNA methylation to silence transposons (TEs). DNA methylation therefore appears to have been co-opted in evolution from an original function in TE management to a developmental function (gene regulation) in both phenotypic plasticity and in normal development. The significance of DNA methylation to the evolution of developmental complexity in plants lies in its role in the management of developmental pathways. As such it is more important in fine tuning the presence, absence, and placement of organs rather than having a central role in the evolution of new organs. Nevertheless, its importance should not be underestimated as it contributes considerably to the range of phenotypic expression and complexity available to plants: the subject of the emerging field of epi-evodevo. Furthermore, changes in DNA methylation can function as a "soft" mutation that may be important in the early stages of major evolutionary novelty.
迄今为止，所有已检测的陆地植物都利用DNA甲基化来沉默转座子（TEs）。因此，DNA甲基化在进化过程中似乎已从TE管理的原始功能被征用到表型可塑性和正常发育中的发育功能（基因调控）。DNA甲基化对植物发育复杂性进化的重要性在于其在发育途径管理中的作用。因此，它在微调器官的存在、缺失和位置方面更为重要，而不是在新器官的进化中起核心作用。然而，其重要性不应被低估，因为它对植物可用的表型表达范围和复杂性有很大贡献：这是新兴的表观进化发育生物学领域的主题。此外，DNA甲基化的变化可以作为一种“软”突变，在重大进化新奇性的早期阶段可能很重要。
