"UC Berkeley researchers have discovered how Cas1-Cas2, the proteins responsible for the ability of the CRISPR immune system in bacteria to adapt to new viral infections, identify the site in the genome where they insert viral DNA so they can recognize it later and mount an attack."
A protein called IHF (blue) creates a sharp turn in the DNA (red helix) upstream of the CRISPR repeat (brown helix), allowing Cas1-Cas2 (green and yellow) to recognize and bind the insertion site. (Addison Wright image)