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CRISPR Immunological Memory Requires a Host Factor for Specificity
- Source :
- Molecular Cell. 62:824-833
- Publication Year :
- 2016
- Publisher :
- Elsevier BV, 2016.
-
Abstract
- Summary Bacteria and archaea employ adaptive immunity against foreign genetic elements using CRISPR-Cas systems. To generate immunological memory, the Cas1-Cas2 protein complex captures 30–40 base pair segments of foreign DNA and catalyzes their integration into the host genome as unique spacer sequences. Although spacers are inserted strictly at the A-T-rich leader end of CRISPR loci in vivo, the molecular mechanism of leader-specific spacer integration remains poorly understood. Here we show that the E. coli integration host factor (IHF) protein is required for spacer acquisition in vivo and for integration into linear DNA in vitro. IHF binds to the leader sequence and induces a sharp DNA bend, allowing the Cas1-Cas2 integrase to catalyze the first integration reaction at the leader-repeat border. Together, these results reveal that Cas1-Cas2-mediated spacer integration requires IHF-induced target DNA bending and explain the elusive role of CRISPR leader sequences during spacer acquisition.
- Subjects :
- DNA, Bacterial
Integration Host Factors
0301 basic medicine
Time Factors
Base pair
CRISPR-Associated Proteins
Computational biology
Adaptive Immunity
Article
Structure-Activity Relationship
03 medical and health sciences
chemistry.chemical_compound
0302 clinical medicine
Escherichia coli
CRISPR
Clustered Regularly Interspaced Short Palindromic Repeats
Molecular Biology
Host factor
Genetics
Binding Sites
Endodeoxyribonucleases
biology
Escherichia coli Proteins
Cell Biology
Endonucleases
biology.organism_classification
Acquired immune system
Integrase
030104 developmental biology
chemistry
CRISPR Loci
biology.protein
Nucleic Acid Conformation
CRISPR-Cas Systems
Immunologic Memory
030217 neurology & neurosurgery
DNA
Protein Binding
Archaea
Subjects
Details
- ISSN :
- 10972765
- Volume :
- 62
- Database :
- OpenAIRE
- Journal :
- Molecular Cell
- Accession number :
- edsair.doi.dedup.....c0113c684a5a14c0bc7511d6a5bfa016