Skip to main content

Research Repository

Advanced Search

DNA replication roadblocks caused by Cascade interference complexes are alleviated by RecG DNA repair helicase

Howard, Jamieson L.; Killelea, Tom; Hawkins, Michelle; Howard, Jamieson; McGlynn, Peter; Bolt, Edward L.


Jamieson L. Howard

Michelle Hawkins

Jamieson Howard

Peter McGlynn

Associate Professor


Cascade complexes underpin E. coli CRISPR-Cas immunity systems by stimulating "adaptation" reactions that update immunity and by initiating "interference" reactions that destroy invader DNA. Recognition of invader DNA in Cascade catalysed R-loops provokes DNA capture and its subsequent integration into CRISPR loci by Cas1 and Cas2. DNA capture processes are unclear but may involve RecG helicase, which stimulates adaptation during its role responding to genome instability. We show that Cascade is a potential source of genome instability because it blocks DNA replication and that RecG helicase alleviates this by dissociating Cascade. This highlights how integrating in vitro CRISPR-Cas interference and adaptation reactions with DNA replication and repair reactions will help to determine precise mechanisms underpinning prokaryotic adaptive immunity.


Howard, J. L., Killelea, T., Hawkins, M., Howard, J., McGlynn, P., & Bolt, E. L. (2019). DNA replication roadblocks caused by Cascade interference complexes are alleviated by RecG DNA repair helicase. RNA Biology, 16(4), 543-548.

Journal Article Type Article
Acceptance Date Jun 29, 2018
Online Publication Date Aug 10, 2018
Publication Date Apr 3, 2019
Deposit Date Jul 4, 2018
Publicly Available Date Aug 11, 2019
Journal RNA Biology
Print ISSN 1547-6286
Electronic ISSN 1555-8584
Publisher Taylor & Francis Open
Peer Reviewed Peer Reviewed
Volume 16
Issue 4
Pages 543-548
Keywords Cell Biology; Molecular Biology
Public URL
Publisher URL
Additional Information This is an Accepted Manuscript of an article published by Taylor & Francis in RNA Biology on 10 August 2018, available online:


You might also like

Downloadable Citations