PUBLICATION
Xenopus TRPN1 (NOMPC) localizes to microtubule-based cilia in epithelial cells, including inner-ear hair cells
- Authors
- Shin, J.B., Adams, D., Paukert, M., Siba, M., Sidi, S., Levin, M., Gillespie, P.G., and Grunder, S.
- ID
- ZDB-PUB-050825-8
- Date
- 2005
- Source
- Proceedings of the National Academy of Sciences of the United States of America 102(35): 12572-12577 (Journal)
- Registered Authors
- Sidi, Samuel
- Keywords
- ciliary, mechanosensory, transduction, transient receptor potential channel
- MeSH Terms
-
- Animals
- Base Sequence
- Cilia/metabolism*
- Cloning, Molecular
- DNA/genetics
- Epithelial Cells/metabolism
- Female
- Hair Cells, Auditory, Inner/metabolism
- Immunohistochemistry
- Ion Channels/genetics
- Ion Channels/metabolism*
- Mechanotransduction, Cellular
- Microtubules/metabolism
- Molecular Sequence Data
- Xenopus Proteins/genetics
- Xenopus Proteins/metabolism*
- Xenopus laevis/embryology
- Xenopus laevis/genetics
- Xenopus laevis/metabolism*
- PubMed
- 16116094 Full text @ Proc. Natl. Acad. Sci. USA
Citation
Shin, J.B., Adams, D., Paukert, M., Siba, M., Sidi, S., Levin, M., Gillespie, P.G., and Grunder, S. (2005) Xenopus TRPN1 (NOMPC) localizes to microtubule-based cilia in epithelial cells, including inner-ear hair cells. Proceedings of the National Academy of Sciences of the United States of America. 102(35):12572-12577.
Abstract
In vertebrates, the senses of hearing and balance depend on hair cells, which transduce sounds with their hair bundles, containing actin-based stereocilia and microtubule-based kinocilia. A longstanding question in auditory science is the identity of the mechanically sensitive transduction channel of hair cells, thought to be localized at the tips of their stereocilia. Experiments in zebrafish implicated the transient receptor potential (TRP) channel NOMPC (drTRPN1) in this role; TRPN1 is absent from the genomes of higher vertebrates, however, and has not been localized in hair cells. Another candidate for the transduction channel, TRPA1, apparently is required for transduction in mammalian and nonmammalian vertebrates. This discrepancy raises the question of the relative contribution of TRPN1 and TRPA1 to transduction in nonmammalian vertebrates. To address this question, we cloned the TRPN1 ortholog from the amphibian Xenopus Xenopus laevis, generated an antibody against the protein, and determined the protein's cellular and subcellular localization. We found that TRPN1 is prominently located in lateral-line hair cells, auditory hair cells, and ciliated epidermal cells of developing Xenopus embryos. In ciliated epidermal cells TRPN1 staining was enriched at the tips and bases of the cilia. In saccular hair cells, TRPN1 was located prominently in the kinocilial bulb, a component of the mechanosensory hair bundles. Moreover, we observed redistribution of TRPN1 upon treatment of hair cells with calcium chelators, which disrupts the transduction apparatus. This result suggests that although TRPN1 is unlikely to be the transduction channel of stereocilia, it plays an essential role, functionally related to transduction, in the kinocilium.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping