Scgn is essential for peak GLP-1 secretion in mGLUTag L -cells. mGLUTag L-cells were treated with scRNA or Scgn siRNA, synchronized and then 8 or 20 h later treated with 10−7 M GIP or vehicle for 2 h. The cells were then analyzed for Bmal1 (A), Per2 (B), Scgn (C), SCGN (a representative blot is shown) (D), and GLP-1 secretion (E) (n = 8, conducted as 4 replicates from each of 2 independent splits). *p < 0.05, **p < 0.01, ***p < 0.001.