Chronological analysis with Fluorescent Timer reveals unique features of newly generated β cells
- Takeshi Miyatsuka1,2,3,6,
- Taka-aki Matsuoka3,
- Shugo Sasaki3,
- Fumiyo Kubo3,
- Iichiro Shimomura3,
- Hirotaka Watada1,2,
- Michael S. German4 and
- Manami Hara5
- 1Department of Metabolism and Endocrinology,
- 2Center for Molecular Diabetology, Juntendo University Graduate School of Medicine, Tokyo, Japan,
- 3Department of Metabolic Medicine, Osaka University Graduate School of Medicine, Osaka, Japan,
- 4Diabetes Center, University of California San Francisco, San Francisco, California, USA,
- 5Department of Medicine, University of Chicago, Chicago, Illinois, USA
- 6Corresponding Author: Takeshi Miyatsuka, E-mail:
While numerous studies have uncovered the molecular mechanisms regulating pancreas development, it remains to be clarified how β cells arise from progenitors, and how recently specified β cells are different from pre-existing β cells. To address these questions, we developed a mouse model in which the insulin 1 promoter drives DsRed-E5 “Timer” fluorescence that shifts its spectrum over time. In the transgenic embryos, green-fluorescent β-cells were readily detected by FACS and could be distinguished from mature β cells only until postnatal day 0, suggesting that β cell neogenesis occurs exclusively during embryogenesis. Transcriptome analysis with green-fluorescent cells sorted by FACS demonstrated that newly differentiated β cells highly expressed progenitor markers, such as Sox9, Neurog3, and Pax4, showing the progenitor-like features of newborn β cells. Flow cytometric analysis of cell cycle dynamics showed that green-fluorescent cells were mostly quiescent, and differentiated β cells were mitotically active. Thus, the precise temporal resolution of this model enables us to dissect the unique features of newly specified insulin-producing cells, which could enhance our understanding of β cell neogenesis for future cell therapy.
- Received August 25, 2013.
- Accepted May 6, 2014.
- © 2014 by the American Diabetes Association.
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