Kim Hyerim, Jang Woo Young, Kang Min-Cheol, Jeong Jain, Choi Minjee, Sung Yonghun, Park Song, Kwon Wookbong, Jang Soyoung, Kim Myoung Ok, Kim Sung Hyun, Ryoo Zae Young
School of Life Science and Biotechnology, KNU Creative BioResearch Group (BK21 plus project), Kyungpook National University, 1370 Sankyuk-dong, Buk-ku, Daegu 702-701, Republic of Korea.
School of Life Science and Biotechnology, KNU Creative BioResearch Group (BK21 plus project), Kyungpook National University, 1370 Sankyuk-dong, Buk-ku, Daegu 702-701, Republic of Korea.
Biochem Biophys Res Commun. 2016 Mar 18;471(4):437-43. doi: 10.1016/j.bbrc.2016.02.060. Epub 2016 Feb 18.
Epigenetic mechanisms are relevant to development and contribute to fetal neurogenesis. DNA methylation and demethylation contribute to neural gene expression during mouse brain development. Ten-eleven translocation 1 (TET1) regulates DNA demethylation by converting 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC). TET1 specifically regulates 5hmC in the central nervous system (CNS), including during neurogenesis in the adult brain. However little is known about its function in fetal neurogenesis. In order to evaluate the role of TET1 in fetal brain development, we generated TET1-overexpressing transgenic (TG) mice. TET1 overexpression was confirmed in the brains of fetal mice, and we detected 5hmC overexpression in the TG brains compared to that in the wild type (WT) brains, using a dot-blot assay. In order to observe the role of TET1 in fetal brain development, we examined fetal brain samples at varied time points by using real-time PCR, Western blotting, and Immunofluorescence (IF). We confirmed that TET1 contributes to neurogenesis by upregulating the protein expressions of neuronal markers in the TG mouse brains, as determined by Western blotting. However the cortex structure or brain mass between WT and TG mice showed no significant difference by IF. In conclusion, TET1 makes the start time of neurogenesis earlier in the TG brains compared to that in the WT brains during fetal brain development.
表观遗传机制与发育相关，并有助于胎儿神经发生。DNA甲基化和去甲基化在小鼠大脑发育过程中对神经基因表达有贡献。10-11易位蛋白1（TET1）通过将5-甲基胞嘧啶（5mC）转化为5-羟甲基胞嘧啶（5hmC）来调节DNA去甲基化。TET1在中枢神经系统（CNS）中特异性调节5hmC，包括在成人大脑的神经发生过程中。然而，其在胎儿神经发生中的功能尚不清楚。为了评估TET1在胎儿大脑发育中的作用，我们构建了过表达TET1的转基因（TG）小鼠。在胎儿小鼠的大脑中证实了TET1的过表达，并且我们使用斑点印迹法检测到与野生型（WT）大脑相比，TG大脑中5hmC过表达。为了观察TET1在胎儿大脑发育中的作用，我们通过实时PCR、蛋白质印迹和免疫荧光（IF）在不同时间点检查胎儿脑样本。通过蛋白质印迹确定，我们证实TET1通过上调TG小鼠大脑中神经元标志物的蛋白表达来促进神经发生。然而，通过IF检测，WT和TG小鼠之间的皮质结构或脑质量没有显著差异。总之，在胎儿大脑发育过程中，与WT大脑相比，TET1使TG大脑中神经发生的起始时间更早。
