The regulatory architecture of gene expression variation in C. elegans revealed by multi-strain allele-specific...

Area of Science:

• Evolutionary biology
• Genomics
• Molecular biology

Background:

• Gene expression evolution is shaped by neutral processes and natural selection.
• Understanding regulatory mechanisms (cis and trans) is key to gene expression variation.

Purpose of the Study:

• To evaluate gene expression evolution in wild C. elegans strains.
• To characterize regulatory architecture and inheritance of expression variation.
• To assess relationships between expression variation and genomic factors.

Main Methods:

• Analysis of allele-specific and between-strain expression in seven wild C. elegans strains.
• Assessment of gene expression variation relative to nucleotide diversity and evolutionary history.
• Replication of findings using human expression data.

Main Results:

• Stabilizing selection is a dominant force maintaining expression phenotypes.
• Genes with higher overall expression exhibit fewer expression differences.
• Evidence for directional selection driving expression divergence, accelerating with genomic divergence.
• Widespread cis differences compensated in trans were observed.

Conclusions:

• Stabilizing selection plays a major role in C. elegans gene expression.
• Expression divergence accelerates with increasing genomic divergence.
• An interactive web application is provided for community access to data.