Wnt Signaling is Dispensable to Formation of the First Tooth in \u3ci\u3eD. Rerio\u3c/i\u3e

The process of tooth formation is highly regulated in time and space by a number of diffusible molecular signals. Several studies have indicated the importance of Wnt signaling during D. rerio odontogenesis, but incomplete expression data has obscured the role Wnt plays in specifying tooth number and position. Using a combination of chemical inhibition and gene expression data gathered from GFP reporter transgenic lines, I have evaluated how requirements for Wnt signaling change throughout the process of tooth formation. My findings indicate that Wnt inhibition has no effect on the first tooth to develop, but prevents the formation of all subsequent teeth. This suggests that the first tooth is developmentally unique from subsequent teeth and that Wnt is required during multiple stages of tooth formation. Further work is needed to identify the mechanism by which the first tooth develops independently of Wnt