Fig. 4: Gene expression and functional studies with barr1-deficient mouse and human beta-cells.
From: β-Arrestin-1 is required for adaptive β-cell mass expansion during obesity
a siRNA-mediated knockdown of barr1 expression in mouse MIN6-K8 cells. Pdx1 gene expression was significantly decreased after barr1 knockdown, while barr2 expression remained unchanged. Gene expression data were normalized relative to the expression of β-actin. b siRNA-mediated knockdown of BARR1 expression in human EndoC-βH1 cells. While BARR2 expression remained unchanged, PDX1, MAFA, and INS transcript levels were decreased after BARR1 knockdown. Gene expression data were normalized relative to the expression of HPRT. c Knockdown of BARR1 expression in EndoC-βH1 cells strongly impairs GSIS. Insulin release assays were carried out with EndoC-βH1 cells that had been treated with BARR1 or control (scrambled) siRNA. Cells were incubated with 1 mM glucose, 20 mM glucose, or 30 mM KCl. Insulin secretion was normalized to basal values obtained at 1 mM glucose (=1). Data were given as means ± s.e.m. from four independent experiments. P values are indicated in the different panels (unpaired two-tailed t-test). Source data are provided as a Source data file.
