Figure 2

Experimental workflow for the comparative proteomic analysis of six different 3T3-L1 cells using 2D-nanoLC-ESI-MS/MS. Protein samples (100 µg) extracted from each cell were reduced, alkylated and digested with trypsin. Each tryptic digest was labelled with six-iTRAQ reagents after purification using SPE cartridges, and 2D-nanoLC-ESI-MS/MS analysis was performed to identify and quantify proteins.