Instituto de Fisiología, Biología Molecular y Neurociencias (IFIByNE), CONICET, Buenos Aires C1428EGA, Argentina.
Departamento de Fisiología, Biología Molecular y Celular (FBMC), Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires C1428EGA, Argentina.
Int J Mol Sci. 2019 Sep 10;20(18):4446. doi: 10.3390/ijms20184446.
Methylation/demethylation of cytosines is an epigenetic strategy for transcriptional regulation, allowing organisms to rapidly respond and adapt to different stimuli. In this context, and using as a plant model, we explored whether an environmental stress is sufficient to trigger a change in the methylation status of Glabra-2, a master gene associated with root epidermal cell differentiation. As this gene acts mainly in the epidermis in the root, we examined the stress-driven methylation levels specifically in that tissue. We focused on the stress caused by different salt concentrations in the growth medium. When testing the effect of 20 and 75 mM NaCl, we found that there is a significant decrease in the CG methylation level of the analyzed genomic region within the epidermis. Whereas this reduction was 23% in mildly stressed plants, it turned out to be more robust (33%) in severely stressed ones. Notably, this latter epigenetic change was accompanied by an increase in the number of trichoblasts, the epidermal cell type responsible for root hair development. Analysis of an eventual inheritance of epigenetic marks showed that the non-stressed progeny (F1) of stressed plants did not inherit-in a Lamarckian fashion-the methylation changes that had been acquired by the parental individuals.
胞嘧啶的甲基化/去甲基化是一种表观遗传调控策略，使生物体能够快速响应和适应不同的刺激。在这种情况下，我们以 作为植物模型，探讨了环境应激是否足以引发与根表皮细胞分化相关的主基因 Glabra-2 的甲基化状态的变化。由于该基因主要在根的表皮中起作用，我们专门在该组织中检查了应激驱动的甲基化水平。我们专注于由生长介质中不同盐浓度引起的应激。当测试 20 和 75 mM NaCl 的影响时，我们发现表皮中分析的基因组区域的 CG 甲基化水平显著降低。在轻度应激的植物中，这种减少了 23%，而在严重应激的植物中则更为显著（33%）。值得注意的是，这种后成的表观遗传变化伴随着 Trichoblasts（负责根毛发育的表皮细胞类型）数量的增加。对潜在的表观遗传标记的遗传分析表明，应激植物的非应激后代（F1）没有以拉马克式的方式继承亲本个体获得的甲基化变化。
