Sox8 is sufficient to reprogram ectoderm into ear vesicles and associated neurons

The vertebrate inner ear arises from a pool of progenitors with the potential to give rise to all the sense organs and cranial ganglia of the head1-6. Here we explore the molecular mechanisms that control ear specification from these precursors. Using a multi-omics approach combined with loss-of-function experiments we identify a core transcriptional circuit that imparts ear identity, along with non-coding elements that integrate this information. This analysis places the transcription factor Sox8 at the top of the ear determination network. Introducing Sox8 into cranial ectoderm not only converts non-ear cells into ear progenitors, but also activates the cellular programmes for ear morphogenesis and neurogenesis. Thus, Sox8 emerges as a master regulator of ear identity and may be a key factor for sense organ cell reprogramming.