Journal Article
Divergent tooth development mechanisms of Mexican tetra fish (Astyanax mexicanus) of Pachon cave origin
Atukorallaya, D., Bhatia, V. and Gonzales, J.
Record Number:
6133
Year:
2023
Journal:
Cells and Development
Pages:
1-8
Volume:
173 203823
Abstract:
The Mexican tetra (Astyanax mexicanus) is one of the fresh water teleost fish models in evolutionary developmental
biology. The existence of two morphs: eyed, pigmented surface fish and blind depigmented cavefish from
multiple cave populations, provides a unique system to study adaptive radiation. Compared to the adult surface
fish, cavefish have large oral jaws with an increased number of structurally-complex teeth. Early tooth development
has not been studied in detail in cavefish populations. In this study, bone-stained growth series and vital
dye staining was used to trace the development and replacement of dentitions in Pach´on cavefish. Our results
show that first tooth eruption was delayed in cavefish compared to the surface fish. In particular, the first tooth
eruption cycle persisted until 35 days post fertilization (dpf). Unlike surface fish, there are multicuspid teeth in
cavefish first generation dentition. In addition to the teeth in the marginal oral jaw bones, Pach´on cavefish have
teeth in the ectopterygoid bone of the palatine roof. Next, we characterised the expression of ectodysplasin
signalling pathway genes in tooth-forming regions of surface and cavefish. Interestingly, higher expression of Eda
and Edar was found in cavefish compared to the surface fish. The altered ectodysplasin expression needs further
investigation to confirm the different molecular mechanisms for tooth development in the oral and pharyngeal
regions of surface fish and cavefish.
Times Cited:
1
Relevent Species: