Among twenty-three diFgfsent Fgfs and four FGF receptors, several are known to function in early otic induction and sensory specification [8], [44], [45], [46], [47].
Using this procedure, we found that genes that exhibit a 2-fold or greater expression in SOPs versus epithelial cells were mainly associated with Gene Ontology (GO) terms related with cell fate determination and sensory organ specification.
Our analysis revealed that genes exhibiting a two-fold or greater expression in SOPs were mainly associated with gene ontology (GO) term related to sensory organ specification and neurogenesis.
Furthermore, neither genes already known to belong to SOP-enriched genor nor genes associated with GO terms related with cell fate determination and sensory organ specification were found in this SOP non-enriched set of genes.
The developmental complexity of sensory neuron specification has been extensively analyzed (Lallemend and Ernfors, 2012), but the links to function remain obscure.
During neural differentiation in early embryonic development, the pro-neural induction factor Neurogenin 2 (Neurog2) is required for primary sensory neuron specification [ 111].
The differentiation of nociceptor precursors into nonpeptidergic and peptidergic nociceptors is a well-studied example of postmitotic sensory neuron subtype specification.
However, it remains to be determined to what extent β-catenin transactivation signaling as opposed to other functions, such as β-catenin-mediated adhesion and TCF/β-catenin-mediated de-repression, controls sensory neuronal subtype specification and DRG formation.
Thus non-sensory development may require the prior specification of sensory tissue.
Finally, zebrafish prdm1 is required to enable Notch signalling pathway-mediated specification of sensory neurons [25], [28].
