Figure 2From: A novel whole-cell lysate kinase assay identifies substrates of the p38 MAPK in differentiating myoblastsMethodology used to identify in vitro kinase substrates using FSBA and quantitative mass spectrometry. The differential tagging of peptides with dimethyl labels allows for the relative quantification and identification of phosphopeptides simultaneously in a high-mass accuracy mass spectrometer. An example/theoretical substrate identification for the added kinase (green) is shown and is based on the higher intensity of the phosphopeptide in MS.Back to article page