Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada.
Genome. 2020 May;63(5):253-262. doi: 10.1139/gen-2019-0190. Epub 2020 Feb 13.
Epigenetic changes influence gene expression and contribute to the modulation of biological processes in response to the environment. Transgenerational epigenetic changes in gene expression have been described in many eukaryotes. However, plants appear to have a stronger propensity for inheriting novel epialleles. This mini-review discusses how plant traits, such as meristematic growth, totipotency, and incomplete epigenetic erasure in gametes promote epiallele inheritance. Additionally, we highlight how plant biology may be inherently tailored to reap the benefits of epigenetic metastability. Importantly, environmentally triggered small RNA expression and subsequent epigenetic changes may allow immobile plants to adapt themselves, and possibly their progeny, to thrive in local environments. The change of epigenetic states through the passage of generations has ramifications for evolution in the natural and agricultural world. In populations containing little genetic diversity, such as elite crop germplasm or habitually self-reproducing species, epigenetics may provide an important source of heritable phenotypic variation. Basic understanding of the processes that direct epigenetic shifts in the genome may allow for breeding or bioengineering for improved plant traits that do not require changes to DNA sequence.
表观遗传变化影响基因表达，并有助于调节生物过程以响应环境。在许多真核生物中已经描述了基因表达的跨代表观遗传变化。然而，植物似乎更有可能遗传新的表观等位基因。这篇小型综述讨论了植物的特征，如分生组织生长、全能性和配子中不完全的表观遗传擦除，如何促进表观等位基因的遗传。此外，我们强调了植物生物学如何内在地适应利用表观遗传不稳定性的优势。重要的是，环境触发的小 RNA 表达和随后的表观遗传变化可能使不能移动的植物适应其自身及其后代在当地环境中茁壮成长。通过世代传递的表观遗传状态的变化对自然和农业世界的进化有影响。在遗传多样性较少的种群中，如精英作物种质或习惯性自繁殖物种，表观遗传学可能提供了遗传表型变异的重要来源。对指导基因组中表观遗传转变的过程的基本理解，可以用于培育或生物工程，以改善不需要改变 DNA 序列的植物特性。
