Fig. 7.

Quantitation of BRAF protein forms in RKO cell lines. The BRAF wild type V600 tryptic peptide IGDFGLATVK and the V600E tryptic peptide IGDFGLATEK tryptic peptide were measured by PRM with quantitation by SID. Integrated peptide peak areas for the single best transition for each peptide were normalized to the corresponding transition for the isotopically labeled peptide standard, and an external calibration curve was used to determine the concentration of wild type and mutant BRAF in RKO cells. The solid blue line indicates the LLOQ for the wild type BRAF peptide (40 amol), and the solid red line indicates the LLOQ for the mutant BRAF peptide (8 amol). Total BRAF is the sum of the amount of wild type BRAF and mutant BRAF in each biological replicate. Error bars represent standard deviation.