Abstract
Virus-mediated expression of CRISPR/Cas9 is commonly used for genome editing in animal brains to model or treat neurological diseases, but the potential neurotoxicity of overexpressing bacterial Cas9 in the mammalian brain remains unknown. Through RNA sequencing (RNA-seq) analysis, we find that virus-mediated expression of Cas9 influences the expression of genes involved in neuronal functions. Reducing the half-life of Cas9 by tagging with geminin, whose expression is regulated by the cell cycle, maintains the genome editing capacity of Cas9 but significantly alleviates neurotoxicity. Thus, modification of Cas9 by shortening its half-life can help develop CRISPR/Cas9-based therapeutic approaches for treating neurological disorders.