MicroRNA and mRNA integrated transcriptional analysis in a Cx30-/- mouse model of non-syndromic hearing loss and deafness [miRNA]

The GJB6 gene is located just 35 kb telomeric to GJB2 in the so-called nonsyndromic hearing loss and deafness locus 1 (DFNB1). Knock out mouse models confirmed that inner ear expression of their protein products, connexin 30 (Cx30) and connexin 26 (Cx26), is crucial for hearing acquisition and normal development of the organ of Corti, however the coordinated regulation mechanism of Cx26 and Cx30 expression in the cochlea remains unclear. To investigate the mechanism underlying the etiopathogenesis of DFNB1, we used a microRNA (miRNA) and mRNA integrated expression profiling analysis on Cx30 -/- mice, which represent a model for humans in which large deletions in the DFNB1 locus lead to the down-regulation of both connexins and profound deafness. MiRNA profiling of cochlear tissue from Cx30 wild-type mice at P5, and their age-matched homozygous knock-out siblings (Cx30-/-) were analysed by using G3 Mouse miRNA Microarray, Release 21, 8×60K (Agilent Technologies). Four biological replicates for each of the two genotypes were used. After the evaluation of quality control parameters for each scanned microarray images, the raw data of three replicates for wild-type and four replicates for knock-out experimental conditions were further analyzed.