Fig. 4

Overexpression of miR-690 impaired the functions of terminal iPSCs-derived IPCs. This group of experiments tested the functions of iPSCs-derived IPCs on day 21 of the second step. a Flow cytometry plots illustrating the protein expression of insulin in populations of iPSCs-derived IPCs. Black text indicates the percentage of insulin. b Glucose-stimulated insulin secretion in vitro. iPSCs-derived IPCs on day 21 of the third step were exposed to different glucose concentrations (0, 5, 15, and 45 mM). The insulin concentration levels were determined. c Quantitative RT-PCR analysis of the mRNA expression levels of key endocrine markers (insulin1, insulin2, GCG, SST, GCK, Mafa, ISL, Glut2). GAPDH was used as the internal control. Error bars show mean ± standard deviation (SD) (n = 3). *P < 0.05, **P < 0.01, ***P < 0.001. d Immunofluorescence assays of protein expression levels of some key markers. Co-immunostaining of insulin (red) with C-peptide (green), insulin (red) with Pdx1 (green), insulin with Nkx6.1 (green); nuclear DAPI staining is shown in blue. Scale bar 75 μm