Fig. 1.

A, The temporal quantitative proteomic analysis of INS-1 cells treated by high palmitate without or with high glucose at five different time points (4, 8, 16, 24, and 48 h). INS-1 cells cultured with BSA were used as control. The experimental workflow included protein extraction, tryptic digestion, 6-plex TMT peptide labeling, offline peptide separation via high-pH reversed-phase chromatography, and 1D-LC-MS/MS analysis of each fraction. B, PCA analysis of all quantifiable proteins (n = 5331) showed the effect of different treatments (PC1 axis) and times (PC2 axis) on the proteome of INS-1 cells. The quantitative result of protein was calculated as a relative TMT ratio normalized by reference samples. C, Unsupervised hierarchical clustering of quantitative changes of DE proteins (n = 783) in PA-/PAG-treated versus BSA-treated INS-1 cells at five time points. The Z-score was transformed from log2 fold change of DE protein by mean normalization.