Conference Paper
Tooth and jaw development in health and disease; Insight form Mexican tetra (Astyanax mexicanus)
Atukorallaya, D., Bhatia, V. and Ratnayake, R.
Record Number:
4322
Year:
2019
Journal:
AIM 2019
Pages:
72
Abstract:
The Mexican tetra (Astyanax mexicanus) is an emerging model in evolutionary developmental
biology. The existence of morphologically distinct surface and cave morphs of this species allows
simultaneous comparative analysis of phenotypic changes at different life stages. This fish has a
diverse distribution in the dentition amongst different morphs and some locations have late tooth
development. The removal of the lens of the one side of the eye alters the expression of key tooth
forming signalling pathway genes such as Sonic hedgehog (Shh), Bone morphogenetic protein 4
(Bmp 4) and Paired-like homeodomain transcription factor 2 (Pitx 2) expression in the developing
jaw area. The present study was designed to compare the development and regeneration
mechanisms of teeth and jaw skeleton among surface and cave morphs. Histological and whole
mount analysis was performed to compare the development of the jaw dentitions. The larval
cavefish has large jaw bones and delayed eruption of teeth. Teeth were found in the pterygoid
bone of the Pachon cavefish. The pterygoid bone teeth are not presented in Tinaja cavefish or
other A. mexicanus populations, suggesting the convergent evolutionary events for constructive
trait development. The base of the skull of A. mexicanus is homologous to the mammalian hard
palate and is made up of ethmoid, parasphenoid, and vomer bone. Micro-computed tomography
(Micro CT) analysis was performed to compare the anatomical arrangement of the palatal bones
among surface and Pachon cavefish. The effect of eye loss on the palatal bones’ development
would provide significant insight into the mammalian cleft palate development.
Times Cited:
1
Conference Name:
Astyanax Interrnational Meeting
Relevent Species: