Figure 1.

Time- and concentration-dependent effects of glucose and GLP-1 on NFAT association with the insulin gene. ChIP-qPCR assays measuring relative fold enrichment of NFATc2 protein on insulin gene promoter DNA in MIN6 cells and human islets in response to increasing concentrations of glucose (A) or GLP-1 in the presence of (B) low (G 2.8mM) and (C) high (G 16.7mM) glucose. Graphed results are expressed as mean ± SD determined from at least 3 independent experiments. Asterisks above bars or next to plots indicate statistically significant differences (*, †, ‡, and §, P < .05; **, ††, ‡‡, and §§, P < .01; ***^, †††, ‡‡‡, and §§§, P < .001) in mean values for treatments compared with 2.8mM glucose controls at corresponding time points based on a one-way ANOVA and Dunnett's multiple comparison post hoc test.