Format

Send to

Choose Destination
J Assoc Res Otolaryngol. 2010 Sep;11(3):395-406. doi: 10.1007/s10162-010-0209-4. Epub 2010 Feb 23.

Maintained expression of the planar cell polarity molecule Vangl2 and reformation of hair cell orientation in the regenerating inner ear.

Author information

1
Fay and Carl Simons Center for the Biology of Hearing and Deafness, Department of Otolaryngology, Washington University School of Medicine, 660 South Euclid Ave., St. Louis, MO 63110, USA. warcholm@ent.wustl.edu

Abstract

The avian inner ear possesses a remarkable ability to regenerate sensory hair cells after ototoxic injury. Regenerated hair cells possess phenotypes and innervation that are similar to those found in the undamaged ear, but little is known about the signaling pathways that guide hair cell differentiation during the regenerative process. The aim of the present study was to examine the factors that specify the orientation of hair cell stereocilia bundles during regeneration. Using organ cultures of the chick utricle, we show that hair cells are properly oriented after having regenerated entirely in vitro and that orientation is not affected by surgical removal of the striolar reversal zone. These results suggest that the orientation of regenerating stereocilia is not guided by the release of a diffusible morphogen from the striolar reversal zone but is specified locally within the regenerating sensory organ. In order to determine the nature of the reorientation cues, we examined the expression patterns of the core planar cell polarity molecule Vangl2 in the normal and regenerating utricle. We found that Vangl2 is asymmetrically expressed on cells within the sensory epithelium and that this expression pattern is maintained after ototoxic injury and throughout regeneration. Notably, treatment with a small molecule inhibitor of c-Jun-N-terminal kinase disrupted the orientation of regenerated hair cells. Both of these results are consistent with the hypothesis that noncanonical Wnt signaling guides hair cell orientation during regeneration.

PMID:
20177731
PMCID:
PMC2914242
DOI:
10.1007/s10162-010-0209-4
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Springer Icon for PubMed Central
Loading ...
Support Center