RNAseq of organ of Corti RNA from mice carrying human mutations in Mir96
Mutations affecting the microRNA miR-96 have been found to cause progressive hearing loss in humans and in mice. These initial mutations were all semidominant, so phenotypes were present in heterozygous carriers. The similarity of the phenotype between the different mutations suggested that it was the loss of normal function of Mir96 that underlay the hearing impairment. However, more recent studies of null alleles of Mir96 and the nearby Mir183, and of Mir96, Mir182 and Mir183 all together, showed that heterozygous carriers of the null alleles have no hearing phenotype, suggesting that the gain of novel targets due to the changed seed sequence resulting from point mutations is important in the Mir96 mutant phenotype, not just the loss of normal targeting. Previous transcriptome analyses of the Mir96 mutant organ of Corti showed that miR-96 controls a broad regulatory network, suggesting that a better understanding of the core genes – particularly the direct targets of miR-96 – may suggest candidate therapeutic targets.  We carried out RNA-seq on mice carrying the two seed region point mutations reported in human families. RNA was extracted from the organ of Corti from four day-old homozygotes and sex-matched wildtype littermates. Strand-specific libraries were prepared following the “TruSeq Stranded mRNA Sample Preparation Guide” with the corresponding kit [Illumina Inc. Cat.# RS-122-2101 or RS-122-2102], and sequenced on an Illumina HiSeq 4000 machine as paired-end 101bp reads.