Targeted transposition with Tn7 elements: safe sites, mobile plasmids, CRISPR/Cas and beyond

Area of Science:

• Molecular Biology
• Genetics
• Microbiology

Background:

• Transposon Tn7 exhibits remarkable control over its transposition, with established pathways targeting chromosomal attachment (att) sites and mobile plasmids.
• Understanding Tn7's integration mechanisms is crucial for comprehending mobile genetic element dynamics.

Purpose of the Study:

• To review newly discovered families of Tn7-like elements and their diverse targeting strategies.
• To highlight the innovative repurposing of CRISPR/Cas systems by Tn7-like elements.
• To explore novel att sites and protein fusions within these expanded Tn7 families.

Main Methods:

• Literature review of recent studies on Tn7-like elements.
• Analysis of genetic mechanisms, including CRISPR/Cas system adaptation.
• Comparative genomics to identify novel att sites and protein architectures.

Main Results:

• Discovery of multiple Tn7-like element families with distinct transposition pathways.
• Identification of Tn7-like elements that repurpose CRISPR/Cas systems to guide transposition into mobile elements.
• Characterization of novel chromosomal att sites facilitating genome island formation.
• Observation of fused or repurposed proteins in new Tn7-like element families.

Conclusions:

• The discovery of diverse Tn7-like elements broadens the understanding of genetic system repurposing.
• These elements present novel tools for genome modification and genomics applications.
• Further research is needed to fully elucidate the impact and potential of these new families.