Different genome stability proteins underpin primed and naïve adaptation in E. coli CRISPR-Cas immunity

CRISPR-Cas is a prokaryotic immune system built from capture and integration of invader DNA into CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) loci, termed ‘Adaptation’, which is dependent on Cas1 and Cas2 proteins. In Escherichia coli, Cascade-Cas3 degrades invader DNA to effec...

Full description

Bibliographic Details
Main Authors: Ivančić-Baće, Ivana, Cass, Simon, Wearne, Stephen J., Bolt, Edward L.
Format: Article
Published: Oxford University Press 2015
Online Access:https://eprints.nottingham.ac.uk/31310/
_version_ 1848794174207295488
author Ivančić-Baće, Ivana
Cass, Simon
Wearne, Stephen J.
Bolt, Edward L.
author_facet Ivančić-Baće, Ivana
Cass, Simon
Wearne, Stephen J.
Bolt, Edward L.
author_sort Ivančić-Baće, Ivana
building Nottingham Research Data Repository
collection Online Access
description CRISPR-Cas is a prokaryotic immune system built from capture and integration of invader DNA into CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) loci, termed ‘Adaptation’, which is dependent on Cas1 and Cas2 proteins. In Escherichia coli, Cascade-Cas3 degrades invader DNA to effect immunity, termed ‘Interference’. Adaptation can interact with interference (‘primed’), or is independent of it (‘naïve’). We demonstrate that primed adaptation requires the RecG helicase and PriA protein to be present. Genetic analysis of mutant phenotypes suggests that RecG is needed to dissipate R-loops at blocked replication forks. Additionally, we identify that DNA polymerase I is important for both primed and naive adaptation, and that RecB is needed for naïve adaptation. Purified Cas1-Cas2 protein shows specificity for binding to and nicking forked DNA within single strand gaps, and collapsing forks into DNA duplexes. The data suggest that different genome stability systems interact with primed or naïve adaptation when responding to blocked or collapsed invader DNA replication. In this model, RecG and Cas3 proteins respond to invader DNA replication forks that are blocked by Cascade interference, enabling DNA capture. RecBCD targets DNA ends at collapsed forks, enabling DNA capture without interference. DNA polymerase I is proposed to fill DNA gaps during spacer integration.
first_indexed 2025-11-14T19:12:00Z
format Article
id nottingham-31310
institution University of Nottingham Malaysia Campus
institution_category Local University
last_indexed 2025-11-14T19:12:00Z
publishDate 2015
publisher Oxford University Press
recordtype eprints
repository_type Digital Repository
spelling nottingham-313102020-05-04T17:22:40Z https://eprints.nottingham.ac.uk/31310/ Different genome stability proteins underpin primed and naïve adaptation in E. coli CRISPR-Cas immunity Ivančić-Baće, Ivana Cass, Simon Wearne, Stephen J. Bolt, Edward L. CRISPR-Cas is a prokaryotic immune system built from capture and integration of invader DNA into CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) loci, termed ‘Adaptation’, which is dependent on Cas1 and Cas2 proteins. In Escherichia coli, Cascade-Cas3 degrades invader DNA to effect immunity, termed ‘Interference’. Adaptation can interact with interference (‘primed’), or is independent of it (‘naïve’). We demonstrate that primed adaptation requires the RecG helicase and PriA protein to be present. Genetic analysis of mutant phenotypes suggests that RecG is needed to dissipate R-loops at blocked replication forks. Additionally, we identify that DNA polymerase I is important for both primed and naive adaptation, and that RecB is needed for naïve adaptation. Purified Cas1-Cas2 protein shows specificity for binding to and nicking forked DNA within single strand gaps, and collapsing forks into DNA duplexes. The data suggest that different genome stability systems interact with primed or naïve adaptation when responding to blocked or collapsed invader DNA replication. In this model, RecG and Cas3 proteins respond to invader DNA replication forks that are blocked by Cascade interference, enabling DNA capture. RecBCD targets DNA ends at collapsed forks, enabling DNA capture without interference. DNA polymerase I is proposed to fill DNA gaps during spacer integration. Oxford University Press 2015-11-17 Article PeerReviewed Ivančić-Baće, Ivana, Cass, Simon, Wearne, Stephen J. and Bolt, Edward L. (2015) Different genome stability proteins underpin primed and naïve adaptation in E. coli CRISPR-Cas immunity. Nucleic Acids Research . pp. 1-10. ISSN 1362-4962 http://nar.oxfordjournals.org/content/43/22/10821.short doi:10.1093/nar/gkv1213 doi:10.1093/nar/gkv1213
spellingShingle Ivančić-Baće, Ivana
Cass, Simon
Wearne, Stephen J.
Bolt, Edward L.
Different genome stability proteins underpin primed and naïve adaptation in E. coli CRISPR-Cas immunity
title Different genome stability proteins underpin primed and naïve adaptation in E. coli CRISPR-Cas immunity
title_full Different genome stability proteins underpin primed and naïve adaptation in E. coli CRISPR-Cas immunity
title_fullStr Different genome stability proteins underpin primed and naïve adaptation in E. coli CRISPR-Cas immunity
title_full_unstemmed Different genome stability proteins underpin primed and naïve adaptation in E. coli CRISPR-Cas immunity
title_short Different genome stability proteins underpin primed and naïve adaptation in E. coli CRISPR-Cas immunity
title_sort different genome stability proteins underpin primed and naïve adaptation in e. coli crispr-cas immunity
url https://eprints.nottingham.ac.uk/31310/
https://eprints.nottingham.ac.uk/31310/
https://eprints.nottingham.ac.uk/31310/