NMDA receptors are anchored by PSD-95 proteins and PSD-95 is anchored by
guanylate-kinase-associated proteins (GKAPs).  Shank proteins (consist of
ankyrin repeats, SH3 domain, a PDZ domain and long proline-rich domain)
provide a scaffold for several neurotransmitter complexes.  The proline rich
part, consists of a homer ligand motif, enabling the binding a homer-mGluR
complex.  Shank may recruit IP3R into the synapse as well.