Site-specific nucleases (SSNs) have drawn much attention in plant biotechnology due to their ability to drive precision mutagenesis, gene targeting or allele replacement. However, when devoid of its nuclease activity, the underlying DNA-binding activity of SSNs can be used to bring other protein functional domains close to specific genomic sites, thus expanding further the range of applications of the technology. In particular, the addition of functional domains encoding epigenetic effectors and chromatin modifiers to the CRISPR/Cas ribonucleoprotein complex opens the possibility to introduce targeted epigenomic modifications in plants in an easily programmable manner. Here we examine some of the most important agronomic traits known to be controlled epigenetically and review the best studied epigenetic catalytic effectors in plants, such as DNA methylases/demethylases or histone acetylases/deacetylases and their associated marks. We also review the most efficient strategies developed to date to functionalize Cas proteins with both catalytic and non-catalytic epigenetic effectors, and the ability of these domains to influence the expression of endogenous genes in a regulatable manner. Based on these new technical developments, we discuss the possibilities offered by epigenetic editing tools in plant biotechnology and their implications in crop breeding.

位点特异性核酸酶 (SSN) 因其能够驱动精确诱变、基因打靶或等位基因替换而在植物生物技术中备受关注。然而，当缺乏其核酸酶活性时，SSN 的潜在 DNA 结合活性可用于将其他蛋白质功能域靠近特定基因组位点，从而进一步扩大该技术的应用范围。特别是，在 CRISPR/Cas 核糖核蛋白复合物中添加编码表观遗传效应子和染色质修饰符的功能域，为以易于编程的方式在植物中引入靶向表观基因组修饰开辟了可能性。在这里，我们研究了一些已知受表观遗传控制的最重要的农艺性状，并回顾了植物中研究得最好的表观遗传催化效应器，例如 DNA 甲基化酶/去甲基化酶或组蛋白乙酰化酶/去乙酰化酶及其相关标记。我们还回顾了迄今为止开发的使用催化和非催化表观遗传效应器功能化 Cas 蛋白的最有效策略，以及这些域以可调节方式影响内源基因表达的能力。基于这些新技术发展，我们讨论了表观遗传编辑工具在植物生物技术中提供的可能性及其对作物育种的影响。以及这些结构域以可调节方式影响内源基因表达的能力。基于这些新技术发展，我们讨论了表观遗传编辑工具在植物生物技术中提供的可能性及其对作物育种的影响。以及这些结构域以可调节方式影响内源基因表达的能力。基于这些新技术发展，我们讨论了表观遗传编辑工具在植物生物技术中提供的可能性及其对作物育种的影响。