Transcriptomic analysis and EdnrB expression in cochlear intermediate cells reveal developmental differences between inner ear and skin melanocytes.

In the inner ear the neural crest gives rise to the glia of the VIIIth ganglion and two types of melanocytic cells: the pigmented cells of the vestibular system, and intermediate cells of the stria vascularis. We analyzed the transcriptome of neonatal intermediate cells in an effort to better understand the development of the stria vascularis. We found that expression of endothelin receptor B, which is essential for melanocyte development persists in intermediate cells long after birth. In contrast, skin melanocytes rapidly downregulate expression of EdnrB. Our findings suggest that endothelins might have coopted new functions in the inner ear during evolution of the auditory organ.