Developing a sense of taste

Taste buds are found in a distributed array on the tongue surface, and are innervated by cranial nerves that convey taste information to the brain. For nearly a century, taste buds were thought to be induced by nerves late in embryonic development. However, this view has shifted dramatically. A host of studies now indicate that taste bud development is initiated and proceeds via processes that are nerve-independent, occur long before birth, and governed by cellular and molecular mechanisms intrinsic to the developing tongue. Here we review the state of our understanding of the molecular and cellular regulation of taste bud development, incorporating important new data obtained through the use of two powerful genetic systems, mouse and zebrafish.

► Early induction and patterning of taste buds occur via processes inherent to the developing tongue.
► Interactions of the Wnt, BMP, Shh and FGF pathways regulate early taste bud formation.
► Signals from the mesenchyme to the overlying epithelium are important regulators of taste bud pattern.
► FGF, Notch and miR-200 signaling control cell fate decisions within multicellular taste buds.
► Molecular genetic approaches in both mouse and zebrafish underlie recent advances in our understanding of taste development.