Expression of connexin 31 in the developing mouse cochlea

Connexin 31 (Cx31) mutations cause an autosomal dominant form of high-frequ ency hearing loss. The immunohistochemical localization of Cx31 in mouse co chlea was studied at different ages between 0 and 60 days after birth (DAB) . Cx31-like immunoreactivity was detected in fibrocytes of spiral ligament and spiral limbus at 12 DAB, gradually enhanced with the increase of age an d reached the adult pattern on 60 DAB. Immunoreactivity decreased gradually from the basal to apical turn in all developmental stages. The mRNA of Cx3 1 was also identified by RT-PCR. The distribution of Cx31 and connexin 26 w ere obviously different in the developing mouse cochlea. The expression and distribution of Cx31 in the development may explain the progressive hearin g loss in human Cx31 mutations. NeuroReport 11:2449-2453 (C) 2000 Lippincot t Williams & Wilkins.