Enables several functions, including SH3 domain binding activity; protein C-terminus binding activity; and scaffold protein binding activity. A structural constituent of postsynaptic density. Involved in positive regulation of glutamate receptor signaling pathway and regulation of synapse organization. Located in ciliary membrane and synapse. Is active in glutamatergic synapse and postsynaptic density, intracellular component. Used to study Phelan-McDermid syndrome. Human ortholog(s) of this gene implicated in Phelan-McDermid syndrome and schizophrenia 15. Orthologous to human SHANK3 (SH3 and multiple ankyrin repeat domains 3). [provided by Alliance of Genome Resources, Apr 2022]