Developmental Plasticity of Patterned and Regenerating Oral Organs

Area of Science:

• Developmental Biology
• Evolutionary Biology
• Comparative Anatomy

Background:

• Teeth and taste buds often coexist in aquatic vertebrates, with taste buds continuously renewed and teeth cyclically replaced.
• Cichlid fish studies offer novel insights into the development and regeneration of these oral organs.

Purpose of the Study:

• To review recent findings on the shared developmental pathways and plasticity between teeth and taste buds.
• To discuss the implications of this plasticity for craniofacial organ patterning and regeneration.

Main Methods:

• Comparative analysis of tooth and taste bud densities across cichlid species with varied feeding strategies.
• Investigation of shared genetic control and molecular signaling pathways.
• Examination of developmental stages, including early patterning and later regeneration phases.
• Experimental manipulation of BMP signaling to assess organ fate conversion.

Main Results:

• Tooth and taste bud densities show positive covariation across species, linked to common genetic regions and molecular signals.
• Developing teeth and taste buds originate from a shared bipotent epithelium and utilize a common epithelial ribbon for regeneration.
• BMP signaling manipulation can convert dental organs to taste bud fate during both patterning and regeneration.

Conclusions:

• A remarkable plasticity exists between dental and sensory organ types in vertebrates.
• Shared developmental programs and signaling pathways underlie the formation and regeneration of teeth and taste buds.
• These findings expand our understanding of craniofacial organ development and evolutionary potential.