组蛋白H3K79同型半胱氨酸修饰位点在神经管畸形中的作用

Role of Histone H3K79 Homocysteinylation in the Neural Tube Defects

目的:探讨人类胚胎脑组织中是否存在H3K79同型半胱氨酸修饰(H3K79Hcy)及其在神经管畸形(NTDs)中的作用。方法:通过质谱检测组蛋白H3K79是否存在同型半胱氨酸修饰位点。进一步合成包含组蛋白H3K79位点的同型半胱氨酸(Hcy)修饰的肽段,并与牛血清白蛋白(BSA)偶联后免疫兔子得到抗组蛋白H3K79Hcy多克隆抗体,并对抗体进行特异性检测;采用此抗H3K79Hcy抗体比较人类高Hcy NTDs样本和正常对照样本的H3K79Hcy水平。结果:(1)人胚胎组织组蛋白H3K79位点存在同型半胱氨酸修饰;(2)高Hcy水平NTDs脑组织中H3K79Hcy修饰水平高于正常对照(P<0.05)。结论:人胚胎组织存在H3K79Hcy修饰,此修饰异常可能促进神经管畸形的发生。

Objective：To verify whether there is H3 K79 homocysteinylation（H3 K79 Hcy） in human embryonic brain tissue and its role in human neural tube defects（NTDs）.Methods：Mass spectrometry was used to detect the H3 K79 Hcy sites in human brain tissue.Further,the peptide containing H3 K79 Hcy was coupled with bovine serum albumin（BSA）.Then the H3 K79 Hcy peptide-BSA was immunized rabbits to obtain anti H3 K79 Hcy polyclonal antibody.Then the anti H3 k79 Hcy antibody specificity was detected.Finally,specific antibody was used to compare the level of H3 K79 Hcy between high Hcy level human NTDs and normal control samples.Results：（1）The lysine of H3 K79 was homocysteinylated in human embryonic brain tissue;（2）The level of H3 K79 Hcy in the NTDs brain with high Hcy level was found to be higher than that of the normal control（P0.05）.Conclusion：The lysine of H3 K79 in human fetal brain was homocysteinylated and the abnormal H3 K79 Hcy may promote the occurrence of neural tube defects.