TIGR-Tas: A family of modular RNA-guided DNA-targeting systems in prokaryotes and their viruses

• 成果类型: Article
• 署名作者: Faure, Guilhem; Saito, Makoto; Wilkinson, Max E.; Quinones-Olvera, Natalia; Xu, Peiyu; Flam-Shepherd, Daniel; Kim, Stephanie; Reddy, Nishith; Zhu, Shiyou; Evgeniou, Lilia; Koonin, Eugene V.; Macrae, Rhiannon K.; Zhang, Feng
• 署名单位: Howard Hughes Medical Institute; Massachusetts Institute of Technology (MIT); Harvard University; Massachusetts Institute of Technology (MIT); Broad Institute; Massachusetts Institute of Technology (MIT); Massachusetts Institute of Technology (MIT); Harvard University; Harvard University; National Institutes of Health (NIH) - USA; NIH National Library of Medicine (NLM)
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-13777
• DOI: 10.1126/science.adv9789
• 发表日期: 2025-05-01
• 关键词: small nucleolar rnas; crispr-cas systems; protein-structure; ribose methylation; preribosomal rna; noncoding rnas; endonuclease; genes; expression; EVOLUTION

摘要

RNA-guided systems provide remarkable versatility, enabling diverse biological functions. Through iterative structural and sequence homology-based mining starting with a guide RNA-interaction domain of Cas9, we identified a family of RNA-guided DNA-targeting proteins in phage and parasitic bacteria. Each system consists of a tandem interspaced guide RNA (TIGR) array and a TIGR-associated (Tas) protein containing a nucleolar protein (Nop) domain, sometimes fused to HNH (TasH)- or RuvC (TasR)-nuclease domains. We show that TIGR arrays are processed into 36-nucleotide RNAs (tigRNAs) that direct sequence-specific DNA binding through a tandem-spacer targeting mechanism. TasR can be reprogrammed for precise DNA cleavage, including in human cells. The structure of TasR reveals striking similarities to box C/D small nucleolar ribonucleoproteins and IS110 RNA-guided transposases, providing insights into the evolution of diverse RNA-guided systems.