Otic vesicle the lateral side will be paraxial mesoderm. Neural crest cells will migrate rostral and caudal to the placode. The general sequence in formation of the otic vesicle is relatively conserved across vertebrates, although there is much variation in timing and stages. Patterning during morphogenesis into the distinctive inner ear structures is determined by homeobox transcription factors including PAX2, DLX5 and DLX6, with the former specifying for ventral otic vesicle derived auditory structures and the latter two specifying for dorsal vestibular structures. The otic vesicle is derived from the cranial placode. The early otic vesicle is characterized as having broad competence
Otic vesicle suggested to play a role in otic induction in mice, as were Msx genes suggested to play a role in otic vesicle formation in chicks. Pax8 is expressed during the entirety of otic vesicle formation. Other genes found in the otic vesicle across species that may play a role in patterning include Hmx, Fox, Dlx, and Gbx genes. Formation of the otic vesicle has been studied extensively in developmental model organisms including chick, Xenopus, zebrafish, axolotyl, & mouse. The transition from the otic placode to the otic vesicle occurs during the 19th somite stage in Zebrafish, Xenopus, and chick. In