Faculty of Natural Sciences, Institute of Biology, Biotechnology and Environmental Protection, University of Silesia in Katowice, Jagiellońska 28, 40-032 Katowice, Poland.
Int J Mol Sci. 2020 Sep 18;21(18):6849. doi: 10.3390/ijms21186849.
The auxin-induced embryogenic reprogramming of plant somatic cells is associated with extensive modulation of the gene expression in which epigenetic modifications, including DNA methylation, seem to play a crucial role. However, the function of DNA methylation, including the role of auxin in epigenetic regulation of the SE-controlling genes, remains poorly understood. Hence, in the present study, we analysed the expression and methylation of the genes that play a critical regulatory role during SE induction (, , , and ) in auxin-treated explants of Arabidopsis. The results showed that auxin treatment substantially affected both the expression and methylation patterns of the SE-involved genes in a concentration-dependent manner. The auxin treatment differentially modulated the methylation of the promoter (P) and gene body (GB) sequences of the SE-involved genes. Relevantly, the SE-effective auxin treatment (5.0 µM of 2,4-D) was associated with the stable hypermethylation of the P regions of the SE-involved genes and a significantly higher methylation of the P than the GB fragments was a characteristic feature of the embryogenic culture. The presence of auxin-responsive (AuxRE) motifs in the hypermethylated P regions suggests that auxin might substantially contribute to the DNA methylation-mediated control of the SE-involved genes.
植物体细胞的生长素诱导胚胎发生重编程与基因表达的广泛调节有关，其中表观遗传修饰（包括 DNA 甲基化）似乎起着关键作用。然而，DNA 甲基化的功能，包括生长素在 SE 控制基因的表观遗传调控中的作用，仍知之甚少。因此，在本研究中，我们分析了拟南芥生长素处理外植体中参与 SE 诱导的基因（、、、和）的表达和甲基化。结果表明，生长素处理以浓度依赖的方式显著影响参与 SE 的基因的表达和甲基化模式。生长素处理差异调节 SE 参与基因的启动子（P）和基因体（GB）序列的甲基化。相关地，有效的 SE 生长素处理（5.0 μM 2,4-D）与 SE 参与基因的 P 区域的稳定超甲基化相关联，并且 P 比 GB 片段的甲基化显著更高是胚胎发生培养的一个特征。在超甲基化的 P 区域存在生长素反应元件（AuxRE）基序表明，生长素可能对 SE 参与基因的 DNA 甲基化介导的控制有很大贡献。
