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bioRxiv · 10.1101/811455

Poor concordance of floxed sequence recombination in single neural stem cells: Implications for cell autonomous studies

Dause, T. J.·Kirby, E. D.
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Abstract

To manipulate target gene function in specific adult cell populations, tamoxifen-dependent CreERT2 is widely used to drive inducible, site-specific recombination of LoxP flanked sequences. In studies of cell autonomous target gene function, it is common practice to combine these CreERT2-lox systems with a ubiquitously-expressed stop-floxed fluorescent reporter gene to identify single cells supposedly undergoing target gene recombination. Here, we studied the reliability of using Cre-induced recombination of one gene to predict recombination in another gene at the single cell level in adult hippocampal neural stem and progenitor cells. Using two separate stop-floxed reporters plus a Nestin promoter-driven CreERT2, we found that, in individual cells, expression of one reporter was a poor predictor of expression of the other. These findings imply that use of stop-floxed reporters to investigate cell autonomous gene function is likely to lead to false conclusions because recombination in separate genes shows poor concordance in individual cells.

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Dause, T. J., Kirby, E. D.. 2019-10-21. Poor concordance of floxed sequence recombination in single neural stem cells: Implications for cell autonomous studies. https://doi.org/10.1101/811455

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