Chronological analysis with fluorescent timer reveals unique features of newly generated β-cells.
Although 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 preexisting 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 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.
Department of Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan Center for Molecular Diabetology, Juntendo University Graduate School of Medicine, Tokyo, Japan Department of Metabolic Medicine, Osaka University Graduate School of Medicine, Osaka, Japan miyatsuka-takeshi@umin.net.
Takeshi
T
Miyatsuka
Department of Metabolic Medicine, Osaka University Graduate School of Medicine, Osaka, Japan.
Taka-aki
TA
Matsuoka
Department of Metabolic Medicine, Osaka University Graduate School of Medicine, Osaka, Japan.
Shugo
S
Sasaki
Department of Metabolic Medicine, Osaka University Graduate School of Medicine, Osaka, Japan.
Fumiyo
F
Kubo
Department of Metabolic Medicine, Osaka University Graduate School of Medicine, Osaka, Japan.
Iichiro
I
Shimomura
Department of Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan Center for Molecular Diabetology, Juntendo University Graduate School of Medicine, Tokyo, Japan.
Hirotaka
H
Watada
Diabetes Center, University of California San Francisco, San Francisco, CA.
Michael S
MS
German
Department of Medicine, The University of Chicago, Chicago, IL.
Manami
M
Hara
D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000378:metabolism; D002454:Cell Differentiation; D005434:Flow Cytometry; D018398:Homeodomain Proteins / Q000378:metabolism; D007328:Insulin / Q000378:metabolism*; D050417:Insulin-Secreting Cells / Q000166:cytology / Q000378:metabolism*; D051379:Mice; D008822:Mice, Transgenic; D009419:Nerve Tissue Proteins / Q000378:metabolism; D051761:Paired Box Transcription Factors / Q000378:metabolism; D011401:Promoter Regions, Genetic; D055758:SOX9 Transcription Factor / Q000378:metabolism
D051792:Basic Helix-Loop-Helix Proteins; D018398:Homeodomain Proteins; D007328:Insulin; D009419:Nerve Tissue Proteins; D051761:Paired Box Transcription Factors; D055758:SOX9 Transcription Factor; C407737:Neurog3 protein, mouse; C110218:Pax4 protein, mouse; C527933:Sox9 protein, mouse