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bioRxiv · 10.1101/176875

Chemical control of a CRISPR-Cas9 acetyltransferase

Shrimp, J. H.·Grose, C.·Widmeyer, S. R. T.·Jadhav, A.·Meier, J. L.
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Abstract

Lysine acetyltransferases (KATs) play a critical role in the regulation of transcription and other genomic functions. However, a persistent challenge is the development of assays capable of defining KAT activity directly in living cells. Towards this goal, here we report the application of a previously reported dCas9-p300 fusion as a transcriptional reporter of KAT activity. First we benchmark the activity of dCas9-p300 relative to other dCas9-based transcriptional activators, and demonstrate its compatibility with second generation short guide RNA architectures. Next, we repurpose this technology to rapidly identify small molecule inhibitors of acetylation-dependent gene expression. These studies validate a recently reported p300 inhibitor chemotype, and reveal a role for p300s bromodomain in dCas9-p300-mediated transcriptional activation. Comparison with other CRISPR-Cas9 transcriptional activators highlights the inherent ligand tuneable nature of dCas9-p300 fusions, suggesting new opportunities for orthogonal gene expression control. Overall, our studies highlight dCas9-p300 as a powerful tool for studying gene expression mechanisms in which acetylation plays a causal role, and provide a foundation for future applications requiring spatiotemporal control over acetylation at specific genomic loci.

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Shrimp, J. H., Grose, C., Widmeyer, S. R. T., Jadhav, A., Meier, J. L.. 2017-08-16. Chemical control of a CRISPR-Cas9 acetyltransferase. https://doi.org/10.1101/176875

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