BioRender | Nobel Prize in Chemistry 2020
CRISPR Nobel Prize in Chemistry 2020
Biorender
Viral DNA is inserted into the bacterial genome in between the repeated CRISPR sequences
tracrRNAs recongnize CRISPR RNA sequences and target Cas9 enzymes to the CRISPR RNA
The CRISPR RNA:tracrRNA duplexe in cleaved off of the longer pre-crRNA
If the bacterium is infected by the same virus, the Cas9:crRNA generated during the first infection reconizes PAM motifs in the viral genome, enabling target-DNA recognition and Cas9-mediated cleaveage to prevent re-infection.