Putative adapter protein involved in asymmetrical cell division and cell polarization processes. May play a role in the formation of epithelial tight junctions (By similarity). Interacts with PARD6B. Interacts with INSC/inscuteable (By similarity). Partially localized along the cell-cell contact region. Colocalizes with TJP1 to epithelial tight junctions (By similarity). Sequence incomplete. Belongs to the PAR3 family.