SWITCHER, a CRISPR-inducible floxed wild-type Cre regulating CRISPR activity.

Although several Cre-regulated CRISPR/Cas platforms exist, a CRISPR/Cas-controlled Cre-system remains a challenge. Here, we present a genetic switch we term SWITCHER based on a floxed wild-type Cre-construct representing a CRISPR-inducible and self-limiting kill switch. By leveraging CRISPR/Cas12a-mediated crRNA-array maturation, we showcase SWITCHER's dual role-not just as a recombinase but as a CRISPR switch, capable of orchestrating distinct Cas12a/crRNA-encoded programs.