Transposon-encoded nucleases use guide RNAs to promote their selfish spread.

ABSTRACT: Insertion sequences are compact and pervasive transposable elements found in bacteria, which encode only the genes necessary for their mobilization and maintenance¹. IS200- and IS605-family transposons undergo 'peel-and-paste' transposition catalysed by a TnpA transposase², but they also encode diverse, TnpB- and IscB-family proteins that are evolutionarily related to the CRISPR-associated effectors Cas12 and Cas9, respectively^3,4. Recent studies have demonstrated that TnpB and IscB function as RNA-guided DNA endonucleases^5,6, but the broader biological role of this activity has remained enigmatic. Here we show that TnpB and IscB are essential to prevent permanent transposon loss as a consequence of the TnpA transposition mechanism. We selected a

SUBMITTER: Meers C 

PROVIDER: S-EPMC11758364 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature