Post Synaptic Density 93 (PSD 93), also known as chapsyn-110, is one of a family of plasma membrane-associated proteins found in synaptic junctions. PSD 93 is unique among family members in its expression in Purkinje neuron cell bodies and dendrites. PSD 93 has three ~90 amino acid repeats called PDZ domains, a single interior SH3 domain, and a carboxyl-terminal guanylate kinase homology (GuK) domain that is enzymatically inactive. It is hypothesized that PDZ-domain interactions play a role in receptor and channel clustering which contributes to neuronal plasticity.
PSD 93 is believed to participate in the clustering of certain proteins, including N-methyl-D-aspartate (NMDA) receptors and shaker-type potassium channels at the synaptic membrane. There are two principal modes of interaction between PSD 93 and other proteins. NMDA receptors and shaker-type potassium channels both share C-terminal sequence homology consisting of a threonine/serine-X-valine-COOH (T/SXV) motif. Other neuronal proteins that share this motif (beta 1 adrenergic receptor, some serotonin receptors, some sodium channel subunits, and additional potassium channel subunits) may interact with PSD 93 by binding to its PDZ domains. Neuronal nitric oxide synthase (nNOS), which lacks the T/SXV motif but which has its own PDZ domain, has been shown to associate with PSD 93 in vitro through a pseudo-homotypic PDZ-PDZ interaction.
The application notes include recommended starting dilutions; optimal dilutions/concentrations should be determined by the end user.
Use a concentration of 5 µg/ml.
Use a concentration of 3 µg/ml. Detects a band of approximately 110 kDa.Can be blocked with PSD93 peptide (ab5840).
Use a concentration of 1 µg/ml.
Required for perception of chronic pain through NMDA receptor signaling. Regulates surface expression of NMDA receptors in dorsal horn neurons of the spinal cord. Interacts with the cytoplasmic tail of NMDA receptor subunits as well as inward rectifying potassium channels. Involved in regulation of synaptic stability at cholinergic synapses. Part of the postsynaptic protein scaffold of excitatory synapses.
Belongs to the MAGUK family. Contains 1 guanylate kinase-like domain. Contains 3 PDZ (DHR) domains. Contains 1 SH3 domain.
An N-terminally truncated L27 domain is predicted in isoform 2 at positions 1 through 27.
Palmitoylation of isoform 1 is not required for targeting to postsynaptic density.
Cell membrane. Cell junction, synapse, postsynaptic cell membrane, postsynaptic density. Cell junction, synapse. Membrane. Cell projection, axon. Concentrated in soma and postsynaptic density of a subset of neurons.
ICC/IF image of ab2930 stained PC12 cells. The cells were 4% formaldehyde fixed (10 min) and then incubated in 1%BSA / 10% normal goat serum / 0.3M glycine in 0.1% PBS-Tween for 1h to permeabilise the cells and block non-specific protein-protein interactions. The cells were then incubated with the antibody (ab2930, 1µg/ml) overnight at +4°C. The secondary antibody (green) was Alexa Fluor® 488 goat anti-rabbit IgG (H+L) used at a 1/1000 dilution for 1h. Alexa Fluor® 594 WGA was used to label plasma membranes (red) at a 1/200 dilution for 1h. DAPI was used to stain the cell nuclei (blue) at a concentration of 1.43µM.