Poster abstracts

Poster number 38 submitted by Kevin Bosse

A Framework Gene Regulatory Network Controlling Neural Crest Cell Diversification

Kevin M. Bosse (MCDB, The Ohio State University), Arife Unal (MCDB, The Ohio State University), Brigitte L. Arduini (Center for Molecular Neurobiology, The Ohio State University), Paul D. Henion (Center for Molecular Neurobiology, The Ohio State University)

Abstract:
The neural crest is a transient population of embryonic cells that diversifies into a wide variety of cell types including peripheral neurons, pigment cells and elements of the craniofacial skeleton. The mechanisms regulating neural crest cell diversification, however, remain incompletely understood. Previous studies using mutant zebrafish have indicated that the transcription factors foxd3 and tfap2a function early and differentially in the development of neural crest sublineages. We show that zebrafish foxd3^zdf10;tfap2a^low double mutant embryos completely lack all neural crest derivatives. While the initial induction of the neural crest is normal in these embryos, distinct neural crest sublineages fail to be specified. The failure of neural crest cell diversification is accompanied by a loss of neural crest SoxE family gene expression. Restoration of sox9a/b or sox10 function via misexpression differentially rescues sublineage specification and derivative differentiation. These results indicate the functional necessity of foxd3 and tfap2a for neural crest cell diversification and that this requirement is mediated in large part through the regulation of the expression of SoxE family genes.

Keywords: cell fate specification, neural crest, zebrafish