Connexins 26 and 30 are co-assembled to form gap junctions in the cochlea of mice.
The importance of connexins (Cxs) in the cochlear functions has been indicated by the finding that mutations in connexin genes cause a large proportion of sensorineural deafness cases. However, functional roles of connexins in the cochlea are still unclear. In this study, we compared the relative expression levels of 16 different subtypes of mouse connexins in the cochlea. cDNA macroarray hybridizations identified four most prominently expressed connexins (listed in descending order): Cxs 26, 29, 30, and 43. Two of these connexins (Cx26 and Cx30), both belonging to the beta-group, were investigated for their molecular assemblies in the cochlea. Co-immunostaining showed expressions of Cxs 26 and 30 in the same gap junction plaques and their co-assembly was confirmed by co-immunoprecipitation of proteins extracted from the cochlear tissues. The heterologous molecular assembly of connexins is expected to produce gap junctions with biophysical characteristics appropriate for maintaining ionic homeostasis in the cochlea.
Ahmad
Shoab
S
Section on Neurobiology, Leslie and Susan Gonda Department of Cell and Molecular Biology, House Ear Institute, Los Angeles, CA 90057-1922, USA.
Chen
Shanping
S
Sun
Jianjun
J
Lin
Xi
X
D000818:Animals; D003051:Cochlea / Q000166:cytology / Q000378:metabolism*; D000072259:Connexin 26; D000075302:Connexin 30; D017630:Connexins / Q000235:genetics / Q000378:metabolism*; D017629:Gap Junctions / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D051379:Mice; D020411:Oligonucleotide Array Sequence Analysis
D000075302:Connexin 30; D017630:Connexins; C000607042:GJB2 protein, human; C491020:GJB6 protein, human; C100629:Gjb6 protein, mouse; D000072259:Connexin 26