Structural component of the gap junctions in germline cells. Required for differentiation and survival of germline cysts in females and of spermatogonia in males; gap junctional communication between spermatogonia and somatic cyst cells may be required for normal differentiation and survival of spermatogonia. Concentrated at the interface between germline and somatic support cells in spermatogonia, early spermatocytes and germ cells in the ovary. Expressed in nurse cells and oocyte during oogenesis. Uniform expression in imaginal wing disk and low expression in developing imaginal CNS. Expressed in embryonic pole cells and primordial germ cells. Expressed both maternally and zygotically. First seen at the embryonic syncytial blastoderm stage. Belongs to the pannexin family.