A dopamine-induced gene expression signature regulates neuronal function and cocaine response.

Drugs of abuse elevate dopamine levels in the nucleus accumbens (NAc) and alter transcriptional programs believed to promote long-lasting synaptic and behavioral adaptations. Here, we leveraged single-nucleus RNA-sequencing to generate a comprehensive molecular atlas of cell subtypes in the NAc, defining both sex-specific and cell type-specific responses to acute cocaine experience in a rat model system. Using this transcriptional map, we identified an immediate early gene expression program that is up-regulated following cocaine experience in vivo and dopamine receptor activation in vitro. Multiplexed induction of this gene program with a large-scale CRISPR-dCas9 activation strategy initiated a secondary synapse-centric transcriptional profile, altered striatal physiology in vitro, and enhanced cocaine sensitization in vivo. Together, these results define the transcriptional response to cocaine with cellular precision and demonstrate that drug-responsive gene programs can potentiate both physiological and behavioral adaptations to drugs of abuse.

A Neuron-Optimized CRISPR/dCas9 Activation System for Robust and Specific Gene Regulation.

CRISPR-based technology has provided new avenues to interrogate gene function, but difficulties in transgene expression in post-mitotic neurons has delayed incorporation of these tools in the central nervous system (CNS). Here, we demonstrate a highly efficient, neuron-optimized dual lentiviral CRISPR-based transcriptional activation (CRISPRa) system capable of robust, modular, and tunable gene induction and multiplexed gene regulation across several primary rodent neuron culture systems. CRISPRa targeting unique promoters in the complex multi-transcript gene brain-derived neurotrophic factor (Bdnf) revealed both transcript- and genome-level selectivity of this approach, in addition to highlighting downstream transcriptional and physiological consequences of Bdnf regulation. Finally, we illustrate that CRISPRa is highly efficient in vivo, resulting in increased protein levels of a target gene in diverse brain structures. Taken together, these results demonstrate that CRISPRa is an efficient and selective method to study gene expression programs in brain health and disease.