Subterranean Fishes of the World

4325

2019

AIM 2019

75

Astyanax mexicanus is an excellent species to study metabolic adaptation. The cave populations have evolved a variety of different strategies to survive in the extreme cave environment. They are able to withstand long fasting periods in part due to increased appetite and fat deposition, insulin resistance and fatty liver, all without obvious negative health consequences. While some coding mutations responsible for these impressive features have been identified recently, little is known about the regulatory basis of this adaptation. While coding mutations alter the structure and/or function of the protein, non-coding mutations can result in spatial and/or temporal changes in expression level leading to phenotypes with limited pleiotropic effects. In this study, we have focused on non-coding mutations that may be helping cavefish to survive their adverse living conditions and the ability to remain healthy under these metabolic adaptations. We have performed RNA-seq, ATAC-seq and ChIP-seq for various histone modifications and the transcription factor p300 on livers of surface fish and Pachón and Tinaja cavefish. We have identified differentially regulated regions near important candidate genes and find signs of repeated evolution at the epigenetic level. We have identified potential upstream regulatory factors and differentially regulated pathways underlying the differential regulation of metabolic circuits. This study sets the stage in understanding the regulatory network of the metabolic adaptation of cavefish and their ability to stay healthy under adverse metabolic conditions.

1

Astyanax Interrnational Meeting