Figure 8From: A study protocol for quantitative targeted absolute proteomics (QTAP) by LC-MS/MS: application for inter-strain differences in protein expression levels of transporters, receptors, claudin-5, and marker proteins at the blood–brain barrier in ddY, FVB, and C57BL/6J miceEfficiency of enzymatic digestion of plasma membrane proteins: Na+/K+-ATPase (a), Organic anion transporting polypeptide 1a1 (b), Monocarboxylate transporter 1 (c), and Na+/taurocholate co-transporting polypeptide (d) in mouse liver. Plasma membrane proteins of mouse liver were digested with only trypsin for the indicated time at 37°C (dotted line) and with lysyl endopeptidase C for 3 h at 25°C, followed by trypsin for the indicated time at 37°C (solid line). The digestion efficiency (%) was calculated by the following equation: [the absolute amounts of digested peptides at the indicated time] × 100/[the absolute amounts of digested peptides by the 16h digestion].Back to article page