Conditional deletion of N-Myc disrupts neurosensory and non-sensory development of the ear
Version of Record online: 29 MAR 2011
Copyright © 2011 Wiley-Liss, Inc.
Volume 240, Issue 6, pages 1373–1390, June 2011
How to Cite
Kopecky, B., Santi, P., Johnson, S., Schmitz, H. and Fritzsch, B. (2011), Conditional deletion of N-Myc disrupts neurosensory and non-sensory development of the ear. Dev. Dyn., 240: 1373–1390. doi: 10.1002/dvdy.22620
- Issue online: 9 MAY 2011
- Version of Record online: 29 MAR 2011
- Manuscript Accepted: 17 FEB 2011
- NIDCD. Grant Numbers: RO1-DC055095590, RO1-DC007588, DC007588-03S1
- inner ear;
- cell cycle
Ear development requires interactions of transcription factors for proliferation and differentiation. The proto-oncogene N-Myc is a member of the Myc family that regulates proliferation. To investigate the function of N-Myc, we conditionally knocked out N-Myc in the ear using Tg(Pax2-Cre) and Foxg1KiCre. N-Myc CKOs had reduced growth of the ear, abnormal morphology including fused sensory epithelia, disrupted histology, and disorganized neuronal innervation. Using Thin-Sheet Laser Imaging Microscopy (TSLIM), 3D reconstruction and quantification of the cochlea revealed a greater than 50% size reduction. Immunochemistry and in situ hybridization showed a gravistatic organ-cochlear fusion and a “circularized” apex with no clear inner and outer hair cells. Furthermore, the abnormally developed cochlea had cross innervation from the vestibular ganglion near the basal tip. These findings are put in the context of the possible functional relationship of N-Myc with a number of other cell proliferative and fate determining genes during ear development. Developmental Dynamics 240:1373–1390, 2011. © 2011 Wiley-Liss, Inc.