AUTHOR=Massey Jonathan H. , Akiyama Noriyoshi , Bien Tanja , Dreisewerd Klaus , Wittkopp Patricia J. , Yew Joanne Y. , Takahashi Aya 

TITLE=Pleiotropic Effects of ebony and tan on Pigmentation and Cuticular Hydrocarbon Composition in Drosophila melanogaster

JOURNAL=Frontiers in Physiology

VOLUME=10

YEAR=2019

URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2019.00518

DOI=10.3389/fphys.2019.00518

ISSN=1664-042X

ABSTRACT=<p>Pleiotropic genes are genes that affect more than one trait. For example, many genes required for pigmentation in the fruit fly <italic>Drosophila melanogaster</italic> also affect traits such as circadian rhythms, vision, and mating behavior. Here, we present evidence that two pigmentation genes, <italic>ebony</italic> and <italic>tan</italic>, which encode enzymes catalyzing reciprocal reactions in the melanin biosynthesis pathway, also affect cuticular hydrocarbon (CHC) composition in <italic>D. melanogaster</italic> females. More specifically, we report that <italic>ebony</italic> loss-of-function mutants have a CHC profile that is biased toward long (&gt;25C) chain CHCs, whereas <italic>tan</italic> loss-of-function mutants have a CHC profile that is biased toward short (&lt;25C) chain CHCs. Moreover, pharmacological inhibition of dopamine synthesis, a key step in the melanin synthesis pathway, reversed the changes in CHC composition seen in <italic>ebony</italic> mutants, making the CHC profiles similar to those seen in <italic>tan</italic> mutants. These observations suggest that genetic variation affecting <italic>ebony</italic> and/or <italic>tan</italic> activity might cause correlated changes in pigmentation and CHC composition in natural populations. We tested this possibility using the <italic>Drosophila</italic> Genetic Reference Panel (DGRP) and found that CHC composition covaried with pigmentation as well as levels of <italic>ebony</italic> and <italic>tan</italic> expression in newly eclosed adults in a manner consistent with the <italic>ebony</italic> and <italic>tan</italic> mutant phenotypes. These data suggest that the pleiotropic effects of <italic>ebony</italic> and <italic>tan</italic> might contribute to covariation of pigmentation and CHC profiles in <italic>Drosophila</italic>.</p>