Down regulated connexin26 at different postnatal stage displayed different types of cellular degeneration and formation of organ of Corti.
Connexin26 (Cx26) mutation is the most common cause for non-syndromic hereditary deafness. Different congenital Cx26 null mouse models revealed a profound hearing loss pattern and developmental defect in the cochlea. Our study aimed at establishing a Cx26 knocking down mouse model at different postnatal time points and to investigate the time course and pattern of the hearing loss and cell degeneration in these models. Morphologic changes were observed for 5 months to detect long-term diversities among these models. Depending on the time point when Cx26 expression was reduced, mild to profound hearing loss patterns were found in different groups. Malformed organ of Corti with distinct cell loss in middle turn was observed only in early Cx26 reduction group while mice in late Cx26 reduction group developed normal organ of Corti and only suffered a few hair loss in the basal turn. These results indicated that Cx26 may play essential roles in the postnatal maturation of the cochlea, and its role in normal hearing at more mature stage may be replaceable.
Department of Otolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, PR China.
Sen
S
Chen
Department of Otolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, PR China. Electronic address: sunyu@hust.edu.cn.
Yu
Y
Sun
Department of Otolaryngology, Emory University School of Medicine, 615 Michael Street, Atlanta, GA 30322-3030, USA.
Xi
X
Lin
Department of Otolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, PR China; Institute of Otorhinolaryngology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, PR China. Electronic address: entwjkong@hust.edu.cn.
Weijia
W
Kong
D000818:Animals; D015153:Blotting, Western; D003051:Cochlea / Q000378:metabolism / Q000473:pathology; D000072259:Connexin 26; D017630:Connexins / Q000235:genetics / Q000378:metabolism*; D015536:Down-Regulation; D015870:Gene Expression; D006198:Hair Cells, Auditory / Q000378:metabolism / Q000473:pathology; D034381:Hearing Loss / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D018345:Mice, Knockout; D008822:Mice, Transgenic; D018613:Microscopy, Confocal; D009925:Organ of Corti / Q000378:metabolism* / Q000473:pathology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors
D017630:Connexins; D000072259:Connexin 26
Cell degeneration; Connexin26; Genetic deafness; Hair cells; Mouse models