Conference Paper
Epigenetic regulation of phenotype of Mexican tetras
Worsham, M., Fang, J. and Yoshizawa, M.
Record Number:
4304
Year:
2019
Journal:
AIM 2019
Pages:
56
Abstract:
Epigenetic mechanisms modify gene expressions in response to factors encountered in the
environment without immediately changing genomic nucleotide composition. These mechanisms
can contribute to genome-wide heritable modifications within a single generation; therefore,
epigenetics has been proposed as one of the drivers of organismal evolution. However, it is largely
unknown how these mechanisms actually play a role in evolution; for example, it is unknown
whether epigenetic modifications contribute to genetic assimilation of certain genotypes, or why
epigenetic regulation affects certain traits but not others. The present research strives to
determine the effects of epigenetics modification in trait evolution within Mexican tetras. This
teleost model has a strong advantage for the study of epigenetics as cave population shows
hypermethylation of cytosine across the genome in comparison with surface populations.
Furthermore, eye size is under control of maternal genetic effects while adaptive foraging
behavior is of paternal genetic effects—both patterns of inheritance could be regulated by
transgenerational epigenetic modifications. Here, we treated both surface fish and cavefish with
inhibitors of DNA methyltransferase (DNMT) and histone deacetylase—increasing transcription;
and methionine, a methyl donor, methionine—decreasing transcription. We targeted the de novo
methylation-active larval stage and raised them to juveniles (4 months old). We then measured
the effect on eye development, foraging behavior, and circadian activity. Our results showed that
treatments with the inhibitor cocktail increased eye-size in cavefish but had no effect in surface
fish, while treatment with the methyl donor reduced eye size in surface fish but had no effect in
cavefish. However, our result indicated that these drug treatments did not affect behavioral
phenotypes in cave or surface fish. We also report our current attempt at a quick methylation
assay system and CpG island profiling.
Times Cited:
1
Conference Name:
Astyanax Interrnational Meeting
Relevent Species: