A light-inducible CRISPR-Cas9 system for control of endogenous gene activation

Modification of the CRISPR/Cas9 genome editing system by the addition of the light inducible proteins CRY2 and CIBI1 enables blue light–mediated transcription of endogenous genes in mammalian cells. Optogenetic systems enable precise spatial and temporal control of cell behavior. We engineered a light-activated CRISPR-Cas9 effector (LACE) system that induces transcription of endogenous genes in the presence of blue light. This was accomplished by fusing the light-inducible heterodimerizing proteins CRY2 and CIB1 to a transactivation domain and the catalytically inactive dCas9, respectively. The versatile LACE system can be easily directed to new DNA sequences for the dynamic regulation of endogenous genes.