His-Me finger (also called HNH or ββα-me) nucleases, are a large superfamily of nucleases that share limited sequence homology, but all members carry a highly similar catalytic motif exhibiting a ββα topology. This review represents a structural comparison of His-Me finger nucleases, summarizing their substrate-binding and recognition strategies, mechanisms of enzymatic hydrolysis, cellular functions, and the various means of activity regulation. His-Me finger nucleases usually function as monomers, making a single nick in nucleic acids to degrade foreign or host genomes, or as homodimers that introduce double-stranded DNA breaks for DNA restriction, integration, recombination, and repair. Various cellular neutralizing machineries have evolved to regulate the activity of His-Me finger nucleases, thereby maintaining genome integrity and cellular functionality.

His-Me手指（也称为HNH或ββ-me）核酸酶，是核酸酶的超家族，共享有限的序列同源性，但所有成员均具有表现出β-β拓扑结构的高度相似的催化基序。这篇综述代表了His-Me手指核酸酶的结构比较，总结了它们的底物结合和识别策略，酶水解机制，细胞功能以及各种活性调节手段。His-Me手指核酸酶通常起单体作用，在核酸中形成单个缺口以降解外来或宿主基因组，或起同二聚体作用，引入双链DNA断裂以限制DNA，整合，重组和修复。已经开发出各种细胞中和机制来调节His-Me手指核酸酶的活性，