线粒体表观遗传学研究进展

Research Progress on Mitochondrial Epigenetics

作为细胞内的"动力工厂",线粒体是细胞内进行氧化磷酸化反应和形成ATP的主要场所。传统观点曾认为线粒体缺乏表观遗传机制,但线粒体DNA甲基化酶以及线粒体DNA中5-甲基胞嘧啶与5-羟甲基胞嘧啶的发现推翻了这一论断。在线粒体中,DNA甲基化酶、DNA甲基化模式及DNA羟甲基化模式与核基因组DNA相比均存在较大差异,而外界环境中不同因子的变化也会对线粒体DNA的甲基化状态造成影响。除此之外,线粒体DNA的表观遗传因素还包括线粒体长链非编码RNA、线粒体mi RNA和线粒体DNA结合蛋白。随着研究技术手段的不断完善,将线粒体DNA的甲基化状态作为生物标记的应用将日益广泛,其与基因组表观遗传调控的关联也将得到进一步的揭示。

As the ＂power house＂ in the cell, mitochondrion is the main organelle to carry out the reaction of oxidative phosphorylation and to generate most of the ATP. Traditionally, it is suggested that mitochondria was lack of any epigenetic mechanism, but the discovery of DNA methyhransferase, 5-methylcytosinc, and 5-hydroxymethylcytosine in mammalian mitochondria in 2011 contradicted with this statement. In mitoehondria, the DNA methyhransferase and the patterns of both DNA methylation and DNA hydroxymethylation are quite different compared with the nuclear genome DNA, and the changes of environmental factors would cause the impacts on the mitochondrial DNA methylation. In addition, epigenetic factors of mitochondrial DNA also include mitochondrial long noncoding RNA, mitochondrial miRNA and mitochondrial DNA binding protein. With the continuous improvement of research techniques, the use of mitochondrial DNA methylation as biomarker will become more extensive and its association with nuclear epigenetics will be further revealed.