Gene expression profile in the cochlear tissue of Cmah-null mouse

CMP-Neu5Ac hydroxylase (Cmah) disruption caused several abnormalities and diseases including hearing loss in old age. However, underling molecular mechanisms that give rise to age-related hearing loss (AHL) in Cmah-null mouse are still obscure. To identify differential gene expression profiles associated with Cmah disruption, we performed microarray analysis using Illumina MouseRef-8 v2 Expression BeadChip, using the cochlear tissues from a control mouse and a Cmah-null mouse. Total RNA was extracted and purified from the cochlear tissues of WT and Cmah-null mice using RNeasy columns (Qiagen; Valencia, CA, USA) according to the manufacturer’s protocol. The RNA quality was verified using an Agilent Bioanalyzer 2100 (Agilent Technologies; Palo Alto, CA, USA) using the RNA 6000 Pico Assay. Generation of double-stranded cDNA, preparation and labeling of cRNA, hybridization to Mouse Ref-8 v2.0 Expression BeadChip (Illumina, Inc.; San Diego, CA, USA), washing, and scanning were all performed according to the standard Illumina protocol. Arrays were scanned using the Illumina Bead Array Reader Confocal Scanner.