Population Genetic and Functional Analysis of a cis-Regulatory Polymorphism in the Drosophila melanogaster Metallothionein A gene

Autor: Timothy J S Ramnarine, Ana Catalán, Amanda Glaser-Schmitt, John Parsch
Jazyk: angličtina
Rok vydání: 2019
Předmět:
Zdroj: Genes
Volume 10
Issue 2
Genes, Vol 10, Iss 2, p 147 (2019)
Popis: Although gene expression can vary extensively within and among populations, the genetic basis of this variation and the evolutionary forces that maintain it are largely unknown. In Drosophila melanogaster, a 49-bp insertion/deletion (indel) polymorphism in the Metallothionein A (MtnA) gene is associated with variation in MtnA expression and oxidative stress tolerance. To better understand the functional and evolutionary significance of this polymorphism, we investigated it in several worldwide populations. In a German population, the deletion was present at a high and stable frequency over multiple seasons and years, and was associated with increased MtnA expression. There was, however, no evidence that the polymorphism was maintained by overdominant, seasonally fluctuating, or sexually antagonistic selection. The deletion was rare in a population from the species&rsquo
ancestral range in sub-Saharan Africa and is likely the result of non-African admixture, suggesting that it spread to high frequency following the species&rsquo
out-of-Africa expansion. Using data from a North American population, we found that the deletion was associated with MtnA expression and tolerance to oxidative stress induced by menadione sodium bisulfite. Our results are consistent with the deletion being selectively favored in temperate populations due to the increased MtnA expression and oxidative stress tolerance that it confers.
Databáze: OpenAIRE