Abstract：
The roots of plants play multiples functions that are essential for growth and development, including anchoring to the soil and water and nutrient acquisition. These underground organs exhibit the plasticity to modify their root system architecture in response to environmental cues allowing adaptation to change in water and nutrient availability. In addition, roots enter in mutualistic interactions with soil microorganisms, e.g. the root nodule symbiosis established between a limited group of plants and nitrogen fixing soil bacteria and the arbuscular mycorrhiza symbiosis involving most land plants and fungi of the Glomeromycetes phylum. In the past 20 years, genetic approaches allowed the identification and functional characterization of genes required for the specific programs of root development, root nodule and arbuscular mycorrhiza symbioses. These genetic studies provided evidence that the program of root nodule symbiosis recruited components of the arbuscular mycorrhiza symbiosis and the root developmental programs. The execution of these programs is strongly influenced by epigenetic changes -DNA methylation and histone post-translational modifications- that alter chromatin conformation modifying the expression of key genes. In this review, we summarize recent advances that highlighted how DNA methylation and histone post-translational modifications, as well as chromatin remodeling factors and long non-coding RNAs, shape the root system architecture and allow the successful establishment of both root nodule and arbuscular mycorrhiza symbioses. We anticipate that the analysis of dynamic epigenetic changes and chromatin 3D structure in specific single-cells or tissue types of root organs will illuminate our understanding of how root developmental and symbiotic programs are orchestrated, opening exciting questions and new perspectives to modulate agronomical and ecological traits linked to nutrient acquisition.
摘要：
植物的根发挥着对生长发育至关重要的多种功能，包括锚定到土壤和水和养分的获取。这些地下器官表现出可塑性，可以根据环境线索改变其根系结构，从而适应水和养分利用率的变化。此外,根系进入与土壤微生物的相互作用，例如，在有限的植物和固氮土壤细菌之间建立的根瘤共生关系，以及涉及大多数陆地植物和肾小球菌门真菌的丛枝菌根共生关系。在过去的20年里,遗传方法允许识别和功能表征的基因所需的具体程序的根发育，根瘤和丛枝菌根共生。这些遗传研究提供了证据，表明根瘤共生程序招募了丛枝菌根共生和根发育程序的组成部分。这些程序的执行受到表观遗传变化的强烈影响-DNA甲基化和组蛋白翻译后修饰-改变染色质构象修饰关键基因的表达。在这次审查中,我们总结了最近的进展，强调了DNA甲基化和组蛋白翻译后修饰，以及染色质重塑因子和长链非编码RNA，塑造根系结构，并成功建立根瘤和丛枝菌根共生。我们预计，对特定单细胞或组织类型的根器官的动态表观遗传变化和染色质3D结构的分析将阐明我们对根发育和共生程序如何编排的理解，打开令人兴奋的问题和新的观点，以调节与养分获取相关的农艺和生态特征。
