Department of Biochemistry, Genetics and Microbiology, Institute of Microbiology, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany.
National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA.
FEMS Microbiol Rev. 2018 May 1;42(3):376-387. doi: 10.1093/femsre/fuy010.
Argonaute (Ago) proteins are encoded in all three domains of life and are responsible for the regulation of intracellular nucleic acid levels. Whereas some Ago variants are able to cleave target nucleic acids by their endonucleolytic activity, others only bind to their target nucleic acids while target cleavage is mediated by other effector proteins. Although all Ago proteins show a high degree of overall structural homology, the nature of the nucleic acid binding partners differs significantly. Recent structural and functional data have provided intriguing new insights into the mechanisms of archaeal and bacterial Ago variants demonstrating the mechanistic diversity within the prokaryotic Ago family with astonishing differences in nucleic acid selection and nuclease specificity. In this review, we provide an overview of the structural organisation of archaeal Ago variants and discuss the current understanding of their biological functions that differ significantly from their eukaryotic counterparts.
Argonaute（AGO）蛋白存在于所有三个生命领域，负责调节细胞内核酸水平。虽然一些 AGO 变体可以通过其内切核酸酶活性切割靶核酸，但其他变体仅与靶核酸结合，而靶核酸的切割则由其他效应蛋白介导。尽管所有 AGO 蛋白显示出高度的整体结构同源性，但核酸结合伙伴的性质却有很大的不同。最近的结构和功能数据为古菌和细菌 AGO 变体的机制提供了有趣的新见解，展示了原核 AGO 家族在核酸选择和核酸酶特异性方面的惊人差异。在这篇综述中，我们概述了古菌 AGO 变体的结构组织，并讨论了目前对其生物学功能的理解，这些功能与真核生物的 AGO 变体有很大的不同。
