The cranial sensory nervous system: specification of sensory progenitors and placodes

The cranial sensory nervous system: specification of sensory progenitors and placodes

Expression of three zebrafish Six4 genes in the cranial sensory placodes and the developing somites

The homeobox gene Six4/AREC3 is a member of the vertebrate Six family of transcription factor genes. In this study we describe the cloning and expression of three zebrafish homologues of Six4/AREC3, six4.1, six4.2 and six4.3. These zebrafish Six4 proteins show high homology to the mammalian Six4/AREC3 proteins in the most C-terminal region in addition to the Six domain and homeodomain. Whole-mo...

The transcriptional regulator Id3 is expressed in cranial sensory placodes during early avian embryonic development

The chick homologue of the helix-loop-helix gene Id3 was isolated, and its expression pattern was analyzed during early stages of chick development. Chick Id3 is dynamically expressed in the olfactory, lens, and otic placodes. It is also observed in the epiphysis, nephric primordium, stomodeum, dermomyotome, distal branchial arches, dorsolateral hindbrain, foregut endoderm, dorsal spinal cord, ...

Eya1 and Six1 are essential for early steps of sensory neurogenesis in mammalian cranial placodes.

Eya1 encodes a transcriptional co-activator and is expressed in cranial sensory placodes. It interacts with and functions upstream of the homeobox gene Six1 during otic placodal development. Here, we have examined their role in cranial sensory neurogenesis. Our data show that the initial cell fate determination for the vestibuloacoustic neurons and their delamination appeared to be unaffected i...

Lens specification is the ground state of all sensory placodes, from which FGF promotes olfactory identity.

The sense organs of the vertebrate head comprise structures as varied as the eye, inner ear, and olfactory epithelium. In the early embryo, these assorted structures share a common developmental origin within the preplacodal region and acquire specific characteristics only later. Here we demonstrate a fundamental similarity in placodal precursors: in the chick all are specified as lens prior to...