Abstract
| I. | Introduction | 267 |
| II. | Isolation of the PSD | 267 |
| III. | Molecular Properties of PSD Constituents | 269 |
| | A. Glutamate Receptors | 269 |
| | B. CaM Kinase II and Protein Kinases | 269 |
| | C. Scaffold and Receptor‐Clustering Molecules | 272 |
| | D. Association Proteins and Adaptor Proteins | 272 |
| | E. Cytoskeletal Proteins | 273 |
| | F. Enzymes | 273 |
| | G. Proteins of Other Classes | 273 |
| | H. Proteins of Other Fractions | 274 |
| IV. | Identification of PSD Proteins Based on Mass Spectrometry | 274 |
| V. | Substrates of Protein Kinases | 274 |
| | A. CaM Kinase II Substrates | 274 |
| | B. PKA and PKC Substrates | 275 |
| | C. Substrates of MAP Kinase Cascade Kinases | 275 |
| | D. Src Family Kinase Substrates | 276 |
| VI. | Regulation of PSD Proteins by Phosphorylation‐Dephosphorylation | 276 |
| | A. NMDA Receptor | 277 |
| | B. AMPA and Kainate Receptors | 278 |
| | C. Metabotropic Glutamate Receptors (mGluRs) | 279 |
| | D. CaM Kinase II | 279 |
| | E. K^+^‐Channel Proteins | 280 |
| | F. Scaffold‐ and Adaptor‐Proteins | 280 |
| | G. nNOS | 280 |
| | H. Dynamin | 281 |
| | I. Membrane Proteins | 281 |
| VII. | Perspectives | 281 |
| VIII. | Conclusions | 282 |
| Abbreviations | 282 |
| References | 282 |
The post‐synaptic density (PSD) contains receptors with associated signaling‐ and scaffolding‐proteins that organize signal‐transduction pathways near the post‐synaptic membrane. The PSD plays an important role in synaptic plasticity, and protein phosphorylation is critical to the regulation of PSD function, including learning and memory. Recently, studies have investigated the protein constituents of the PSD and substrate proteins for various protein kinases by proteomic analysis. The present review focuses on the molecular properties of PSD proteins, and substrates of protein kinases and their regulation by phosphorylation in order to understand the role of PSD in synaptic plasticity. © 2003 Wiley Periodicals, Inc., Mass Spec Rev 21:266–286, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mas.10033