Required for the maturation but not the establishment of septate junctions in developing epithelial cells and is involved in epithelial cell adhesion during septate junction maturation (PubMed:25704509). Plays a role in the proper localization of the septate junction core components pck/mega, kune, Nrx-IV and Nrg during late embryogenesis (PubMed:25704509). Involved in the formation of tricellular junctions which mediate cell contact where three epithelial cells meet but not of bicellular junctions (PubMed:25982676). Required for the accumulation of Gli at tricellular junctions. Found at tricellular contacts. Expression detected in embryonic epithelia and central nervous system (at protein level) (PubMed:25982676). First detected during stage 13 in the tracheal system, the foregut, the hindgut, the salivary glands and the epidermis (PubMed:25704509, PubMed:25982676). Expression persists in these tissues until the end of embryogenesis (PubMed:25704509). Expression in epithelia declines from late stage 15 and expression appears in the central nervous system during stage 16 (PubMed:25982676). N-glycosylated. May be proteolytically cleaved in the extracellular domain. Embryonic lethality. Mutant embryos establish functional septate junctions but, due to rudimentary septae formation during subsequent embryonic development, these become non-functional (PubMed:25704509). Abnormal liquid clearance of tracheal tubes (PubMed:25704509). Convoluted and elongated tracheal branches (PubMed:25704509, PubMed:25982676). During late embryogenesis, mislocalization of septate junction core components pck/mega, kune, Nrx-IV and Nrg and impaired cell adhesion at the lateral cell membrane (PubMed:25704509). Mislocalization of Fas3 in the epithelia of mutant embryos and loss of accumulation of Gli at tricellular junctions (PubMed:25982676). The name 'bark beetle' derives from the convoluted tracheal branches seen in mutant embryos which resemble the tracks of bark beetle larvae (PubMed:25704509). The name 'anakonda' is also based on the convoluted tracheal tube phenotype of mutant embryos (PubMed:25982676).