DOI: 10.5061/dryad.jh52n
title: Data from: Phenotypic plasticity through transcriptional regulation of the evolutionary hotspot gene tan in Drosophila melanogaster

description: Phenotypic plasticity is the ability of a given genotype to produce
 different phenotypes in response to distinct environmental conditions.
 Phenotypic plasticity can be adaptive. Furthermore, it is thought to
 facilitate evolution. Although phenotypic plasticity is a widespread
 phenomenon, its molecular mechanisms are only beginning to be unravelled.
 Environmental conditions can affect gene expression through modification
 of chromatin structure, mainly via histone modifications, nucleosome
 remodelling or DNA methylation, suggesting that phenotypic plasticity
 might partly be due to chromatin plasticity. As a model of phenotypic
 plasticity, we study abdominal pigmentation of Drosophila melanogaster
 females, which is temperature sensitive. Abdominal pigmentation is indeed
 darker in females grown at 18°C than at 29°C. This phenomenon is thought
 to be adaptive as the dark pigmentation produced at lower temperature
 increases body temperature. We show here that temperature modulates the
 expression of tan (t), a pigmentation gene involved in melanin production.
 t is expressed 7 times more at 18°C than at 29°C in female abdominal
 epidermis. Genetic experiments show that modulation of t expression by
 temperature is essential for female abdominal pigmentation plasticity.
 Temperature modulates the activity of an enhancer of t without modifying
 compaction of its chromatin or level of the active histone mark H3K27ac.
 By contrast, the active mark H3K4me3 on the t promoter is strongly
 modulated by temperature. The H3K4 methyl-transferase involved in this
 process is likely Trithorax, as we show that it regulates t expression and
 the H3K4me3 level on the t promoter and also participates in female
 pigmentation and its plasticity. Interestingly, t was previously shown to
 be involved in inter-individual variation of female abdominal pigmentation
 in Drosophila melanogaster, and in abdominal pigmentation divergence
 between Drosophila species. Sensitivity of t expression to environmental
 conditions might therefore give more substrate for selection, explaining
 why this gene has frequently been involved in evolution of pigmentation.
description: raw data
 Fig1Quantification of
 abdominal pigmentation in w1118 females grown at 18°C, 25°C and
 29°C.raw data
 Fig2Expression of
 pigmentation genes in abdominal epidermis of female pharates and adults
 grown at 18°C and 29°Craw data Fig4 and
 S2FigQuantification of
 abdominal pigmentation of tan mutant and control females grown at 18°C,
 25°C and 29°C.raw data
 Fig5Quantification of GFP in
 abdominal segments of t_MSE-nEGFP females grown at 18°C and
 29°Craw data
 Fig6FAIRE-qPCR, ChIP for
 H3K27ac, ChIP for H3K4me3 and IP mockraw data Fig8 and
 S6Figtan relative expression
 in control females and trx RNAi females, ChIP for H3K4me3 in control
 females and trx RNAi females, abdominal pigmentation quantification in
 control females (w1118) and females mutant for trx.raw data
 S3FigGFP quantification in
 abdominal segments of ebony-nEGFP females grown at 18°C and
 29°Craw data
 S4FigRelative expression of
 vg and CG12119 in abdominal epidermis of w1118 females grown at 18°C and
 29°Craw data
 S5FigIP H3/input, IP
 H3K27ac/Input and IP H3K4me3/IP H3 in abdominal epidermis of females grown
 at 18°C and 29°Craw data
 S6FigRelative expression of
 pigmentation genes in control females (RNAi GFP) and RNAi trx
 females