Previously we detected more than 28 PSD proteins to be phosphorylated by CaM kinase II, and identified 14 protein substrates (Yoshimura, Y., Aoi, T., Yamauchi, T., Mol. Brain Res. 81, 118-128, 2000). In the present study, the remaining substrates were analyzed by protein sequencing and mass spectrometry. We found 6 proteins not previously known to be substrates of CaM kinase II, namely PSD95-associated protein, SAP97, TOAD-64, TNF receptor-associated protein, insulin-receptor tyrosine kinase 58153 kDa substrate, and homer 1b. (C) 2002 Elsevier Science (USA).