» Articles » PMID: 37398409

Programmable RNA-guided Endonucleases Are Widespread in Eukaryotes and Their Viruses

Overview
Journal bioRxiv
Date 2023 Jul 3
PMID 37398409
Authors
Affiliations
Soon will be listed here.
Abstract

TnpB proteins are RNA-guided nucleases that are broadly associated with IS200/605 family transposons in prokaryotes. TnpB homologs, named Fanzors, have been detected in genomes of some eukaryotes and large viruses, but their activity and functions in eukaryotes remain unknown. We searched genomes of diverse eukaryotes and their viruses for TnpB homologs and identified numerous putative RNA-guided nucleases that are often associated with various transposases, suggesting they are encoded in mobile genetic elements. Reconstruction of the evolution of these nucleases, which we rename Horizontally-transferred Eukaryotic RNA-guided Mobile Element Systems (HERMES), revealed multiple acquisitions of TnpBs by eukaryotes and subsequent diversification. In their adaptation and spread in eukaryotes, HERMES proteins acquired nuclear localization signals, and genes captured introns, indicating extensive, long term adaptation to functioning in eukaryotic cells. Biochemical and cellular evidence show that HERMES employ non-coding RNAs encoded adjacent to the nuclease for RNA-guided cleavage of double-stranded DNA. HERMES nucleases contain a re-arranged catalytic site of the RuvC domain, similar to a distinct subset of TnpBs, and lack collateral cleavage activity. We demonstrate that HERMES can be harnessed for genome editing in human cells, highlighting the potential of these widespread eukaryotic RNA-guided nucleases for biotechnology applications.

References
1.
Karvelis T, Druteika G, Bigelyte G, Budre K, Zedaveinyte R, Silanskas A . Transposon-associated TnpB is a programmable RNA-guided DNA endonuclease. Nature. 2021; 599(7886):692-696. PMC: 8612924. DOI: 10.1038/s41586-021-04058-1. View

2.
Takeda S, Nakagawa R, Okazaki S, Hirano H, Kobayashi K, Kusakizako T . Structure of the miniature type V-F CRISPR-Cas effector enzyme. Mol Cell. 2020; 81(3):558-570.e3. DOI: 10.1016/j.molcel.2020.11.035. View

3.
Kapitonov V, Makarova K, Koonin E . ISC, a Novel Group of Bacterial and Archaeal DNA Transposons That Encode Cas9 Homologs. J Bacteriol. 2015; 198(5):797-807. PMC: 4810608. DOI: 10.1128/JB.00783-15. View

4.
Nakagawa R, Hirano H, Omura S, Nety S, Kannan S, Altae-Tran H . Cryo-EM structure of the transposon-associated TnpB enzyme. Nature. 2023; 616(7956):390-397. PMC: 10097598. DOI: 10.1038/s41586-023-05933-9. View

5.
Strecker J, Ladha A, Gardner Z, Schmid-Burgk J, Makarova K, Koonin E . RNA-guided DNA insertion with CRISPR-associated transposases. Science. 2019; 365(6448):48-53. PMC: 6659118. DOI: 10.1126/science.aax9181. View