Western blot of 20’ UV treated HeLa lysate showing specific immunolabeling of the ~65 kDa NF-κB p65 phosphorylated at Ser316 in the first lane (-). Phosphospecificity is shown in the second lane (+) where immunolabeling is eliminated by blot treatment with lambda phosphatase (lambda-Ptase, 1200 units for 30 min).