Genotype by environment interaction for gene expression in Drosophila melanogaster

Area of Science:

• Genomics
• Evolutionary Biology
• Molecular Biology

Background:

• Understanding how genetic factors influence phenotypic responses to environmental changes is crucial.
• Gene expression variation is a key component of phenotypic plasticity.
• The genetic architecture of gene expression can be influenced by environmental conditions.

Purpose of the Study:

• To investigate how the genetic architecture of gene expression regulation changes in response to different temperatures.
• To identify the genetic basis of environmentally plastic gene expression in Drosophila melanogaster.

Main Methods:

• Utilized whole-genome quantitative gene expression analysis in fully sequenced inbred Drosophila melanogaster strains.
• Compared gene expression patterns between flies reared at 25°C and 18°C.
• Analyzed genotype-by-environment interactions and expression quantitative trait loci (eQTLs).

Main Results:

• A significant portion of the transcriptome showed genotype-by-environment interaction, indicating plastic genetic architecture.
• Genetic variance in gene expression generally increased at 18°C compared to 25°C.
• Environment-specific eQTLs were enriched for transcription factor binding sites, and co-expression networks remained conserved across temperatures.

Conclusions:

• Gene expression exhibits environmentally plastic genetic architecture, with temperature influencing genetic variance.
• Despite plasticity, gene co-expression networks are robust, likely due to stabilizing selection on highly connected genes.