RT Journal Article
SR Electronic
T1 SspA is a transcriptional regulator of CRISPR adaptation in <em>E. coli</em>
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2024.05.24.595836
DO 10.1101/2024.05.24.595836
A1 Lopez, Santiago C.
A1 Lee, Yumie
A1 Zhang, Karen
A1 Shipman, Seth L.
YR 2024
UL http://biorxiv.org/content/early/2024/05/25/2024.05.24.595836.abstract
AB 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 E. coli Type I-E system. Our screen uncovers a novel host factor, SspA, which transcriptionally regulates 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.Competing Interest StatementThe authors have declared no competing interest.