Hermann A, Gowher H, Jeltsch A
Institut für Biochemie, FB 8, Justus-Liebig-Universität, Heinrich-Buff-Ring 58, 35392, Giessen, Germany.
Cell Mol Life Sci. 2004 Oct;61(19-20):2571-87. doi: 10.1007/s00018-004-4201-1.
DNA methylation is a stable but not irreversible epigenetic signal that silences gene expression. It has a variety of important functions in mammals, including control of gene expression, cellular differentiation and development, preservation of chromosomal integrity, parental imprinting and X-chromosome inactivation. In addition, it has been implicated in brain function and the development of the immune system. Somatic alterations in genomic methylation patterns contribute to the etiology of human cancers and ageing. It is tightly interwoven with the modification of histone tails and other epigenetic signals. Here we review our current understanding of the molecular enzymology of the mammalian DNA methyltransferases Dnmt1, Dnmt3a, Dnmt3b and Dnmt2 and the roles of the enzymes in the above-mentioned biological processes.
DNA甲基化是一种稳定但并非不可逆转的表观遗传信号，可使基因表达沉默。它在哺乳动物中具有多种重要功能，包括基因表达调控、细胞分化与发育、染色体完整性的维持、亲本印记以及X染色体失活。此外，它还与脑功能和免疫系统的发育有关。基因组甲基化模式的体细胞改变与人类癌症的病因和衰老有关。它与组蛋白尾部修饰和其他表观遗传信号紧密交织。在这里，我们综述了目前对哺乳动物DNA甲基转移酶Dnmt1、Dnmt3a、Dnmt3b和Dnmt2的分子酶学以及这些酶在上述生物学过程中的作用的理解。
