Post-synaptic density

Post synaptic density protein/Drosophila disc large tumor suppressor/zonula occuldens-1 protein... 

NMDA and AMPA receptors are spread across the post-synaptic density (PSD), whereas metabotropic glutamate receptors (except mGluR7) are located along the periphery of the PSD (Fig. 15-2). NMDA receptors appear to be present at most or all glutamatergic synapses whereas the content of AMPA receptors is variable - from zero to about 50 receptors per PSD [33]. Some synapses are silent , meaning that activation of them does not elicit AMPA receptor currents when the plasma membrane is hyperpolarized and Mg2+ blocks NMDA receptors. Such silent synapses contain only NMDA receptors. However, AMPA receptors are recruited from the cytosol to the PSD to activate such silent synapses in LTP. 

Akama, K. T. and McEwen, B. S. Estrogen stimulates post-synaptic density-95 rapid protein synthesis via the Akt/ protein kinase B pathway. /. Neurosci. 23 2333-2339,2003. 

K., Miyazawa, S., Endo, S., and Suzuki, T. A novel ubiquitin-specific protease, synUSP, is localized at the post-synaptic density and post-synaptic lipid raft, J Neurochem, 2003, 87, 665-75. 

Sun Y, Savanenin A, Reddy PH, Liu YF (2001) Polyglutamine-expanded huntingtin promotes sensitization of N-methyl-D- aspartate receptors via post-synaptic density 95. J Biol Chem 276 24713-24718. 

The idenhfication of 374 different proteins in the purified post-synaptic density of central excitatory synapses by LC-MS-MS was reported [61]. 13 phosphorylated sites were detected at 8 proteins. They also determined the molar concentrahon and relative stoichiometries of various scaffold proteins in the post-synaptic density. 

Okamoto PM, Gamby C, Wells D, Fallon J, Vallee RB. 2001. Dynamin iso-form-specific interaction with the shank/ proSAP scaffolding proteins of the post-synaptic density and actin cytoskeleton. J. Biol. Chem. 276 48458-65... 

Another approach which has proved to be very successful in the systematic identification of proteins, has been used to identify the molecular constituents of the post-synaptic proteome (PSP) (Husi 2003). The post-synaptic density is an amorphous structure usually 400 nm long and 40 nm wide and is located beneath the synaptic membrane, and is visible under the electron microscope as tight complexes of post-synaptic junctional proteins (Figure 3). It is well established that the regulation of synaptic proteins that occur in the PSP plays an important role in synaptic plasticity, a mechanism which is believed to underlie the synaptic mechanism of learning and memory (Kennedy 1993). 

Protein phosphorylation has been shown to be intimately involved in the assembly and function of the post-synaptic density (Yamauchi 2002), synaptic vesicle turnover (Turner, Burgoyne et al. 1999), LTP (Hedou and Mansuy 2003) and synaptic plasticity/memory (Schulman 1995). It is therefore obvious that study of protein phosphorylation on a proteomic platform will yield a wealth of data relevant to the molecular basis of brain function. 

Yamauchi, T., 2002, Molecular constituents and phosphorylation-dependent regulation of the post-synaptic density. Mass Spectrom. Rev. 21 266-86. 

Alie A, Manuel M. The backbone of the post-synaptic density originated in a unicellular ancestor of choanoflagellates and metazoans. BMC Evol Biol. 2010 10 34. 

Monastyrskaya K, Hostettler A, Buergi S, Draeger A. The NKl receptor localizes to the plasma membrane microdomains, and its activation is dependent on lipid raft integrity. / Biol Chem. 2005 280(8) 7135-7146. Besshoh S, Bawa D, Teves L, Wallace MC, Gurd JW. Increased phosphorylation and redistribution of NMDA receptors between synaptic lipid rafts and post-synaptic densities following transient global ischemia in the rat brain. / Neurochem. 2005 93(1) 186-194. 

GFP [103]. PDZ is a structural domain found in signalling proteins of living organisms and plants (PDZ stands for Post synaptic density protein, Drosophilia disc large mmour suppressor, and Zonula occludens-1) which is a multidomain protein localised at intercellular junctions. Claudin-1 is a human protein which regulates cellular transformation and plays a role in metastatic colon cancer [104]. 

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