Targeted Transcriptional Activation using a CRISPR-Associated Transposon System

Garza Elizondo, A. M.; Chappell, J.

doi:10.1101/2023.09.12.557412

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bioRxiv · 10.1101/2023.09.12.557412

Targeted Transcriptional Activation using a CRISPR-Associated Transposon System

Garza Elizondo, A. M.·Chappell, J.

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Abstract

Synthetic perturbation of gene expression is central to our ability to reliably uncover genotype-phenotype relationships in microbes. Here, we present a novel gene transcription activation strategy that uses the Vibrio cholerae CRISPR-Associated Transposon (CAST) system to selectively insert promoter elements upstream of genes of interest. Through this strategy, we show robust activation of both recombinant and endogenous genes across the E. coli chromosome. We then demonstrate precise tuning of expression levels by exchanging the promoter elements being inserted. Finally, we demonstrate that CAST activation can be used to synthetically induce ampicillin-resistant phenotypes in E. coli.

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Garza Elizondo, A. M., Chappell, J.. 2023-09-12. Targeted Transcriptional Activation using a CRISPR-Associated Transposon System. https://doi.org/10.1101/2023.09.12.557412

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