Symbol: | cas4 |
CRISPR-associated protein 4 | |
Pfam: | PF01930 |
Interpro: | IPR022765 |
Cas4 is an endonuclease found in some CRISPR systems that is used as part of the spacer acquisition stage.Cas4 is required for efficient prespacer processing by forming a Cas4-Cas1-Cas2 complex. [1] In this complex, Cas4 cuts double-stranded substrates with long 3'-overhangs through site-specific endonucleolytic cleavage. [2] Cas4 closely interacts with the integrase active sites of Cas1, recognizes PAM sequences within the substrate and cleaves precisely upstream of them, ensuring the acquisition of functional spacers. [1]