The DNA methyltransferase (DNMT) family comprises a conserved set of DNA-modifying enzymes that have a central role in epigenetic gene regulation. Recent studies have shown that the functions of the canonical DNMT enzymes — DNMT1, DNMT3A and DNMT3B — go beyond their traditional roles of establishing and maintaining DNA methylation patterns. This Review analyses how molecular interactions and changes in gene copy numbers modulate the activity of DNMTs in diverse gene regulatory functions, including transcriptional silencing, transcriptional activation and post-transcriptional regulation by DNMT2-dependent tRNA methylation. This mechanistic diversity enables the DNMT family to function as a versatile toolkit for epigenetic regulation.

DNA甲基转移酶（DNMT）家族包含一组保守的DNA修饰酶，这些酶在表观遗传基因调控中具有重要作用。最近的研究表明，规范DNMT酶DNMT1，DNMT3A和DNMT3B的功能超出了它们建立和维持DNA甲基化模式的传统作用。这篇综述分析了分子相互作用和基因拷贝数的变化如何调节DNMT在多种基因调控功能中的活性，这些功能包括转录沉默，转录激活和依赖DNMT2的tRNA甲基化的转录后调控。这种机制的多样性使DNMT系列可以用作表观遗传调控的多功能工具包。