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Title: SspA is a transcriptional regulator of CRISPR adaptation in E. coli
Abstract The CRISPR integrases Cas1-Cas2 create immunological memories of viral infection by storing phage-derived DNA in CRISPR arrays, a process known as CRISPR adaptation. A number of host factors have been shown to influence adaptation, but the full pathway from infection to a fully integrated, phage-derived sequences in the array remains incomplete. Here, we deploy a new CRISPRi-based screen to identify putative host factors that participate in CRISPR adaptation in the Escherichia coli Type I-E system. Our screen and subsequent mechanistic characterization reveal that SspA, through its role as a global transcriptional regulator of cellular stress, is required for functional CRISPR adaptation. One target of SspA is H-NS, a known repressor of CRISPR interference proteins, but we find that the role of SspA on adaptation is not H-NS-dependent. We propose a new model of CRISPR-Cas defense that includes independent cellular control of adaptation and interference by SspA.  more » « less
Award ID(s):
2137692
PAR ID:
10562365
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Oxford University Press
Date Published:
Journal Name:
Nucleic Acids Research
Volume:
53
Issue:
4
ISSN:
0305-1048
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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