Skip to Main content Skip to Navigation
Journal articles

Casposon integration shows strong target site preference and recapitulates protospacer integration by CRISPR-Cas systems

Abstract : Casposons are a recently discovered group of large DNA transposons present in diverse bacterial and ar-chaeal genomes. For integration into the host chromosome , casposons employ an endonuclease that is homologous to the Cas1 protein involved in proto-spacer integration by the CRISPR-Cas adaptive immune system. Here we describe the site-preference of integration by the Cas1 integrase (casposase) encoded by the casposon of the archaeon Acidulipro-fundum boonei. Oligonucleotide duplexes derived from the terminal inverted repeats (TIR) of the A. boonei casposon as well as mini-casposons flanked by the TIR inserted preferentially at a site reconstituting the original A. boonei target site. As in the A. boonei genome, the insertion was accompanied by a 15-bp direct target site duplication (TSD). The minimal functional target consisted of the 15-bp TSD segment and the adjacent 18-bp sequence which comprises the 3 end of the tRNA-Pro gene corresponding to the TC loop. The functional casposase target site bears clear resemblance to the leader sequence-repeat junction which is the target for protospacer integration catalyzed by the Cas1–Cas2 adaptation module of CRISPR-Cas. These findings reinforce the mechanistic similarities and evolutionary connection between the casposons and the adaptation module of the prokaryotic adaptive immunity systems.
Document type :
Journal articles
Complete list of metadatas

Cited literature [44 references]  Display  Hide  Download

https://hal-pasteur.archives-ouvertes.fr/pasteur-01384627
Contributor : Ana Cova Rodrigues <>
Submitted on : Thursday, October 20, 2016 - 11:44:40 AM
Last modification on : Wednesday, April 29, 2020 - 2:14:15 PM

File

Nucl. Acids Res.-2016-Béguin...
Publication funded by an institution

Licence


Distributed under a Creative Commons Attribution - NonCommercial 4.0 International License

Identifiers

Collections

Citation

Pierre Béguin, Nicole Charpin, Eugene V. Koonin, Patrick Forterre, Mart Krupovic. Casposon integration shows strong target site preference and recapitulates protospacer integration by CRISPR-Cas systems. Nucleic Acids Research, Oxford University Press, 2016, ⟨10.1093/nar/gkw821⟩. ⟨pasteur-01384627⟩

Share

Metrics

Record views

452

Files downloads

475