Pannexins are new molecular candidates for assembling gap junctions in the cochlea.

Genetic studies have linked many nonsyndromic deafness patients to mutations in genes coding for gap junction proteins. To better understand molecular identities of gap junctions in the cochlea, we investigated the expression of pannexins (Panxs). Western blot and reverse transcription-PCR detected the expression of Panx1 and Panx2. Immunolabeling localized Panx1 to the inner and outer sulcus, as well as the Claudius cells. Both Panx1 and Panx2 were expressed in the spiral and Scarpa's ganglion neurons. These data for the first time showed expressions of Panxs in the cochlea, therefore adding a new family of gap junction proteins to those used to form intercellular transport pathways in the cochlea.