Enables PDZ domain binding activity. Predicted to be involved in maintenance of epithelial cell apical/basal polarity; neurotransmitter secretion; and protein localization to basolateral plasma membrane. Located in cell-cell junction and synapse. Orthologous to human LIN7B (lin-7 homolog B, crumbs cell polarity complex component). [provided by Alliance of Genome Resources, Apr 2022]