Consistent specificity and efficiency of tamoxifen-mediated cre induction across ages

Kellogg, C. M.; Pham, K.; Ko, S.; Cox, J. E. J.; Machalinski, A. H.; Stout, M. B.; Sharpe, A. L.; Beckstead, M. J.; Chucair-Elliott, A. J.; Ocanas, S. R.; Freeman, W. M.

doi:10.1101/2023.09.19.558482

bioRxiv · 10.1101/2023.09.19.558482

Consistent specificity and efficiency of tamoxifen-mediated cre induction across ages

Kellogg, C. M.·Pham, K.·Ko, S.·Cox, J. E. J.·Machalinski, A. H.·Stout, M. B.·Sharpe, A. L.·Beckstead, M. J.·Chucair-Elliott, A. J.·Ocanas, S. R.·Freeman, W. M.

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Abstract

Temporally controlling cre recombination through tamoxifen (Tam) induction has many advantages for biomedical research. Most studies report Tam induction at early post-natal/juvenile (<2 m.o.) mouse ages, but age-related neurodegeneration and aging studies can require cre induction in older mice (>12 m.o.). While anecdotally reported as problematic, there are no published comparisons of Tam mediated cre induction at early and late ages. Here, microglial-specific Cx3cr1creERT2 mice were crossed to a floxed NuTRAP reporter to compare cre induction at early (3-6 m.o.) and late (20 m.o.) ages. Specificity and efficiency of microglial labeling at 21-22 m.o. were identical in mice induced with Tam at 3-6 m.o. or 20 m.o. of age. Age-related microglial translatomic changes were also similar regardless of Tam induction age. Each cre and flox mouse line should be validated independently, however, these findings demonstrate that Tam-mediated cre induction can be performed even into older mouse ages.

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Kellogg, C. M., Pham, K., Ko, S., Cox, J. E. J., Machalinski, A. H., Stout, M. B., Sharpe, A. L., Beckstead, M. J., Chucair-Elliott, A. J., Ocanas, S. R., Freeman, W. M.. 2023-09-22. Consistent specificity and efficiency of tamoxifen-mediated cre induction across ages. https://doi.org/10.1101/2023.09.19.558482

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