Related Experiment Video
Updated: Aug 7, 2026
09:09
Cryosectioning and Immunostaining Mouse Inner Ear Tissue: From Embryonic to Adult Stages
Published on: April 11, 2025
Age-related changes in cochlear gene expression in normal and shaker 2 mice
Tzy-Wen L Gong1, I Jill Karolyi, James Macdonald
1Kresge Hearing Research Institute, Department of Otolaryngology/Head-Neck Surgery, University of Michigan Medical School, Ann Arbor, MI 48109-0648, USA.
Summary
Mutations in myosin XV (Myo15) disrupt stereocilia in shaker 2 mice, leading to deafness. Gene expression analysis revealed age-related changes and specific gene upregulations linked to cochlear development and auditory function.
Area of Science:
- Otolaryngology
- Genetics
- Molecular Biology
Background:
- The vertebrate cochlea is crucial for hearing, with auditory hair cells and their stereocilia bundles responsible for sound transduction.
- Mutations in unconventional myosin XV (Myo15) cause deafness (DFNB3) due to stereocilia defects, as observed in shaker 2 (sh2) mice.
Purpose of the Study:
- To investigate the molecular consequences of the Myo15 gene mutation in sh2 mice.
- To identify gene expression changes associated with myosin XV defects and aging in the cochlea.
Main Methods:
- Gene expression profiling using Affymetrix GeneChips in sh2/sh2 mice and heterozygotes (+/sh2) at different ages.
- Microarray data analysis with Robust Multiarray Average (RMA).
- Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) for validation.
Main Results:
- Few genotype-affected genes were identified; however, numerous age-associated expression changes occurred in both normal and mutant mice.
- Upregulation of Aim1, Dbi, and Tm4sf3 was observed in sh2/sh2 homozygotes.
- Age-related gene expression changes involved collagens, extracellular matrix proteins, and bone mineralization pathways.
Conclusions:
- Myosin XV defects impact specific gene expression pathways in the cochlea.
- Age-associated molecular events are crucial for cochlear maturation and auditory function, potentially influenced by myosin XV defects.
