Molecular constituents and phosphorylation‐dependent regulation of the post‐synaptic density

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.