Enables protein-macromolecule adaptor activity and signaling receptor binding activity. Involved in several processes, including egg-laying behavior; positive regulation of vulval development; and protein localization to basolateral plasma membrane. Located in cell-cell junction. Expressed in gonad; head; somatic gonad precursor; somatic nervous system; and vulval precursor cell. Is an ortholog of human LIN7A (
lin-7 homolog A, crumbs cell polarity complex component); LIN7B (
lin-7 homolog B, crumbs cell polarity complex component); and LIN7C (
lin-7 homolog C, crumbs cell polarity complex component).