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bioRxiv · 10.1101/659904

Three-dimensional analysis of β-cell proliferation by a novel mouse model

Tokumoto, S.·Yabe, D.·Tatsuoka, H.·Usui, R.·Fauzi, M.·Botagarova, A.·Goto, H.·Herrera, P. L.·Ogura, M.·Inagaki, N.
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Abstract

Inducing {beta}-cell proliferation could inhibit diabetes progression. Many factors have been suggested as potential {beta}-cell mitogens, but their impact on {beta}-cell replication has not been confirmed due to the lack of a standardized {beta}-cell proliferation assay. In this study, we developed a novel method that specifically labels replicating {beta} cells and yields more reproducible results than current immunohistochemical assays. We established a mouse line expressing the fluorescent ubiquitination-based cell cycle indicator (Fucci2a) reporter only in {beta} cells through Cre-mediated recombination under the control of the rat insulin promoter (RIP-Cre;Fucci2aR). Three-dimensional imaging of optically cleared pancreas tissue from these mice enabled the quantification of replicating {beta} cells in islets and morphometric analysis of islets following mitogen treatment. Intravital imaging of RIP-Cre;Fucci2aR mice revealed cell cycle progression of {beta} cells. Thus, this novel mouse line is a powerful tool for spatiotemporal analysis of {beta}-cell proliferation in response to mitogen stimulation.

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Tokumoto, S., Yabe, D., Tatsuoka, H., Usui, R., Fauzi, M., Botagarova, A., Goto, H., Herrera, P. L., Ogura, M., Inagaki, N.. 2019-06-04. Three-dimensional analysis of β-cell proliferation by a novel mouse model. https://doi.org/10.1101/659904

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