Fig 2: Activity of GAPDH Is Perturbed in SC-ß Cells(A) Quantification of cellular PEP in different GSIS conditions from SC-islets.(B) Western blot of lysates from differentiated SC-ß cells and cadaveric islets for GAPDH and PGK1. These human islet lysates were from samples used in GAPDH and PGK activity assays. Each band is a separate preparation of human islets or differentiation of SC-ß cells.(C) GAPDH enzyme activity in cadaveric islets, undifferentiated human embryonic stem cells (hES), and differentiated SC-ß cells.(D) PGK activity in cadaveric islets, undifferentiated hES cells, and differentiated SC-ß cells.(E) GAPDH western blot of lysates from DSS-cross-linking in primary islets, hES cells, and differentiated SC-ß cells.(F) GSIS on GAPDH and PGK1-overexpressing SC-ß cells.(G) Model of SC-ß cell inhibition of GSIS caused by decreased GAPDH activity underlying decreased PEP flux.The p values were calculated using two-way ANOVA with Dunnett’s multiple hypothesis correction. For all experiments shown, color denotes a unique biological replicate within an experiment. Replicates within a biological group are the same color. Each data point in (C) and (D) represents a unique biological replicate for human islets (separate donors), SC-ß cells (separate differentiations), and hES cells (different passages). Spaces in western blot panels indicate where images from the same experiment were edited together for ease of presentation. Data are represented as mean ± SD.