Dipartimento di Biologia, Ecologia e Scienze della Terra, Università della Calabria, Arcavacata di Rende (CS), 87036 Arcavacata di Rende, CS, Italy; Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium; Center Plant Systems Biology, VIB, 9052 Ghent, Belgium.
Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium; Center Plant Systems Biology, VIB, 9052 Ghent, Belgium.
Plant Sci. 2019 Mar;280:383-396. doi: 10.1016/j.plantsci.2018.12.029. Epub 2019 Jan 3.
DNA methylation carried out by different methyltransferase classes is a relevant epigenetic modification of DNA which plays a relevant role in the development of eukaryotic organisms. Accordingly, in Arabidopsis thaliana loss of DNA methylation due to combined mutations in genes encoding for DNA methyltransferases causes several developmental abnormalities. The present study describes novel growth disorders in the drm1 drm2 cmt3 triple mutant of Arabidopsis thaliana, defective both in maintenance and de novo DNA methylation, and highlights the correlation between DNA methylation and the auxin hormone pathway. By using an auxin responsive reporter gene, we discovered that auxin accumulation and distribution were affected in the mutant compared to the wild type, from embryo to adult plant stage. In addition, we demonstrated that the defective methylation status also affected the expression of genes that regulate auxin hormone pathways from synthesis to transport and signalling and a direct relationship between differentially expressed auxin-related genes and altered auxin accumulation and distribution in embryo, leaf and root was observed. Finally, we provided evidence of the direct and organ-specific modulation of auxin-related genes through the DNA methylation process.
不同甲基转移酶家族所进行的 DNA 甲基化是 DNA 的一种重要表观遗传修饰，在真核生物的发育中起着重要作用。因此，在拟南芥中，由于编码 DNA 甲基转移酶的基因的联合突变导致 DNA 甲基化丧失，会引起几种发育异常。本研究描述了拟南芥中 drm1drm2cmt3 三重突变体的新型生长障碍，该突变体在维持和从头 DNA 甲基化方面均有缺陷，并强调了 DNA 甲基化与生长素激素途径之间的相关性。通过使用生长素反应报告基因，我们发现与野生型相比，在突变体中，从胚胎到成体植物阶段，生长素的积累和分布受到影响。此外，我们证明，有缺陷的甲基化状态也会影响调节生长素激素途径从合成到运输和信号转导的基因的表达，并且观察到差异表达的与生长素相关的基因与胚胎、叶片和根中生长素积累和分布的改变之间存在直接关系。最后，我们通过 DNA 甲基化过程提供了生长素相关基因的直接和器官特异性调节的证据。
