Coupling the Developmental Programs of Teeth and Taste Buds in Malawi Cichlids

Abstract

Epithelial tissue of vertebrate organisms serves as the interface between them and the immediate environment with which they interact. Transformation of this outer tissue layer generates specialized structures that allow organisms to make enhanced or entirely new interactions with its ecological niche. This study examines two structures derived from the oropharyngeal cavity epithelium: teeth and taste buds. Using cichlids from Lake Malawi in eastern Africa as a model, this study seeks to show the co-evolutionary relationship that likely exists between teeth and taste buds. Based on the observations that both teeth and taste buds are derived from the epithelium, are colocalized sensory organs within the oropharyngeal cavity, have very similar structures in early development, and share certain patterns in gene expression, we hypothesize that the gene networks governing tooth and taste bud development are similar. Through comparative morphology and molecular developmental biology, this study shows that both teeth and taste buds share similarities of gene expression in both spatial and temporal patterns.