Figure 2. Linearity of phospho-MYPT1-T697 (A–C) and phospho-MYPT1-T855 (D–F) Western blotting of tissue extracts.

A and D, dilution series of 10 μmol l⁻¹ UTP-stimulated cerebral artery extract was subjected to SDS-PAGE and phosphorylation of MYPT1-T697 and -T855 detected by 3-step Western blotting. B and E, signal intensity plotted against amount of extract loaded for phospho-T697- and phospho-T855-MYPT1 Western blots, and Coomassie Blue-stained actin, showing the linear relationship between the amount of sample loaded and the detected signal intensity (n= 3). C and F, normalization of the signal intensity of phospho-MYPT1 to Coomassie Blue-stained actin produced a linear relationship that did not deviate from the expected value (n= 3).