Enables SH3 domain binding activity and protein C-terminus binding activity. A structural constituent of postsynaptic density. Involved in several processes, including adult locomotory behavior; associative learning; and social behavior. Located in several cellular components, including apical plasma membrane; cell projection membrane; and growth cone. Is active in glutamatergic synapse; hippocampal mossy fiber to CA3 synapse; and postsynaptic density. Used to study autism spectrum disorder. Human ortholog(s) of this gene implicated in autistic disorder. Orthologous to human SHANK2 (SH3 and multiple ankyrin repeat domains 2). [provided by Alliance of Genome Resources, Apr 2022]