Enables protein C-terminus binding activity; protein-macromolecule adaptor activity; and signaling receptor binding activity. Involved in several processes, including oviposition; positive regulation of vulval development; and protein localization to basolateral plasma membrane. Located in cell-cell junction. Predicted to be part of MPP7-DLG1-LIN7 complex. 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).