Expression of the C-terminal domain of mammalian TET3 DNA dioxygenase in Arabidopsis thaliana induces heritable methylation changes at rDNA loci.
Expression of the C-terminal domain of mammalian TET3 DNA dioxygenase in Arabidopsis thaliana induces heritable methylation changes at rDNA loci.
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DOI：
10.4236/abb.2016.75023
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发表时间：
2016-01-01
期刊：
影响因子：
--
通讯作者：
Meyer, P.
中科院分区：
文献类型：
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作者：
Hollwey, E.;Watson, M.;Meyer, P.
在植物中，5-甲基胞嘧啶（5 mC）残基的去甲基化由DNA糖基化酶控制，而在哺乳动物中，它需要由泰特蛋白（一组Fe（II）/2-酮戊二酸依赖性双加氧酶）氧化5 mC。我们分析了在拟南芥中表达人类TET 3基因（TET 3c）的C-末端催化结构域的影响，使用rDNA区域作为甲基化报告基因。在TET 3c转化体中，可以诱导具有低甲基化或高甲基化模式的表观等位基因，即使在去除TET 3c转基因后，其各自也稳定地保留在后代系中。在TET 3c转化体中，检测到5-羟甲基胞嘧啶（5 hmC）标记，指示转基因酶的氧化活性。5-甲酰基胞嘧啶（5 fC）仅在具有DNA糖基化酶突变体背景的TET 3c转化体中可检测到，这表明TET 3c将5 hmC残基进一步氧化为5 fC，并通过植物糖基化酶有效识别和去除5 fC。结果表明，TET 3c可用于诱导DNA甲基化的遗传位点特异性变化，并且5 hmC的积累可用作TET 3c靶区域的标记。
In plants, demethylation of 5-methylcytosine (5 mC) residues is controlled by DNA glycosylases, while in mammals it requires oxidation of 5 mC by TET proteins, a group of Fe(II)/2-oxoglutarate-dependent dioxygenases. We analysed the effects of expressing the C-terminal catalytic domain of the human TET3 gene (TET3c) in Arabidopsis thaliana, using an rDNA region as a methylation reporter. In TET3c transformants, epialleles with hypomethylation or hypermethylation patterns can be induced, which is each stably retained in progeny lines even after removal of the TET3c transgene. In TET3c transformants, 5-hydroxymethylcytosine (5 hmC) marks are detected, indicative of the oxidative activity of the transgenic enzyme. 5-formylcytosine (5 fC) is only detectable in TET3c transformants with a DNA glycosylase mutant background suggesting further oxidation of 5 hmC residues to 5 fC by TET3c, and efficient recognition and removal of 5 fC by plant glycosylases. The results suggest that TET3c can be employed to induce heritable locus-specific changes in DNA methylation, and that accumulation of 5 hmC can be used as a marker for TET3c target regions.