Fig.7

a) Structure of Mass-tagged probe for Protein kinase A.

b) Mass spectrum of cell lysate containing mass-tagged probes. In this case, H-type probe and D-type-probe were added to two lysates from different cell sample, respectively. After 2h, two lysate were combined, and analyzed with MALDI-TOF MS.

c) Development of mass signal for phosphorylated probe in cell lysate in the presence of or absent from forskolin.