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bioRxiv · 10.1101/412932

Predominance of cis-regulatory changes in parallel expression divergence of sticklebacks.

Verta, J.-P.·Jones, F.
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Abstract

Regulation of gene expression is thought to play a major role in adaptation but the relative importance of cis- and trans-regulatory mechanisms in the early stages of adaptive divergence is unclear. Using RNAseq of threespine stickleback fish gill tissue from four independent marine-freshwater ecotype pairs and their F1 hybrids, we show that cis-acting (allele-specific) regulation consistently predominates gene expression divergence. Genes showing parallel marine-freshwater expression divergence are found near to adaptive genomic regions, show signatures of natural selection around their transcription start sites and are enriched for cis-regulatory control. For genes with parallel increased expression among freshwater fish, the quantitative degree of cis- and trans-regulation is also highly correlated across populations, suggesting a shared genetic basis. Compared to other forms of regulation, cis-regulation tends to show greater additivity and stability across different genetic and environmental contexts, making it a fertile substrate for the early stages of adaptive evolution.

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Verta, J.-P., Jones, F.. 2018-09-10. Predominance of cis-regulatory changes in parallel expression divergence of sticklebacks.. https://doi.org/10.1101/412932

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