(b) Caged phosphopeptides before or after UV-A-irradiation were incubated with U2OS cell lysates for 30 min. GST-14-3-3β and ζ beads were added and bound proteins detected as in panel a.

Introduction One of the most important post-translational modifications is phosphorylation of serine, threonine or tyrosine residues. Detection of phosphorylation sites by mass spectrometry in ...