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Updated: Jul 11, 2026
07:07
Evaluation of Planar-Cell-Polarity Phenotypes in Ciliopathy Mouse Mutant Cochlea
Published on: February 21, 2016
Cochlin isoforms and their interaction with CTL2 (SLC44A2) in the inner ear
P K Kommareddi1, T S Nair, Y Raphael
1Immunology and Cell Biology Laboratory, 6020 Kresge Hearing Research Institute, Department of Otolaryngology/Head and Neck Surgery, The University of Michigan, 1301 East Ann Street, Ann Arbor, MI 48109-0506, USA.
Journal of the Association for Research in Otolaryngology : JARO
|October 11, 2007
Summary
Choline transporter-like protein 2 (CTL2) and cochlin interact in the inner ear. This study reveals their co-localization and potential roles in hearing loss and basilar membrane structure.
Area of Science:
- Otorhinolaryngology
- Cell Biology
- Genetics
Background:
- Choline transporter-like protein 2 (CTL2) is implicated in antibody-induced hearing loss.
- Cochlin, mutated in DFNA9 hearing loss, is an abundant inner ear protein.
- The functions of CTL2 and cochlin remain largely unknown.
Purpose of the Study:
- To investigate the interaction between CTL2 and cochlin.
- To elucidate the structural heterogeneity of cochlin isoforms.
- To determine the localization and potential roles of CTL2 and cochlin in the inner ear.
Main Methods:
- Mass spectrometry to identify co-precipitating proteins.
- Antibody generation for cochlin-specific peptide.
- Western blotting and co-immunoprecipitation assays.
- Immunohistochemical analysis of cochlear cross-sections.
Main Results:
- Cochlin was identified as a 64 kDa protein co-precipitating with CTL2.
- Cochlin isoform heterogeneity is due to N-glycosylation and alternative splicing.
- CTL2 and cochlin were shown to co-immunoprecipitate.
- CTL2 expression is broader than previously known, particularly on cells facing the scala media.
- Cochlin exhibits a ribbon-like pattern in the basilar membrane.
Conclusions:
- CTL2 and cochlin interact physically within the inner ear.
- Cochlin's structure is complex, involving post-translational modifications and alternative splicing.
- CTL2 and cochlin are localized in close proximity in various inner ear structures, suggesting functional relevance.
- Cochlin may play a structural role in the basilar membrane.
- The precise functional significance of the CTL2-cochlin interaction requires further investigation.
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