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bioRxiv · 10.1101/2020.06.20.161430

Scalable recombinase-based gene expression cascades

Kim, T.·Weinberg, B.·Wong, W.·Lu, T. K.
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Abstract

Temporal modulation of multiple genes underlies sophisticated biological phenomena. However, there are few scalable and generalizable gene circuit architectures for the programming of sequential genetic perturbations. We describe a modular recombinase-based gene circuit architecture, comprising tandem gene perturbation cassettes (GPCs), that enables the sequential expression of multiple genes in a defined temporal order by alternating treatment with just two orthogonal ligands. We used tandem GPCs to sequentially express single-guide RNAs to encode transcriptional cascades and trigger the sequential accumulation of mutations. We built an all-in-one gene circuit that sequentially edits genomic loci, synchronizes cells at a specific stage within a gene expression cascade, and deletes itself for safety. Tandem GPCs offer a multi-tiered cellular programming tool for modeling multi-stage genetic changes, such as tumorigenesis and cellular differentiation.Competing Interest StatementThe authors have declared no competing interest.View Full Text

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Kim, T., Weinberg, B., Wong, W., Lu, T. K.. 2020-06-20. Scalable recombinase-based gene expression cascades. https://doi.org/10.1101/2020.06.20.161430

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