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Updated: Aug 6, 2026
08:51
Microinjection for Transgenesis and Genome Editing in Threespine Sticklebacks
Published on: May 13, 2016
Genomic landscape underlying pituitary epigenome divergence between stickleback ecotypes
Liang Liu1,2, Jun Kitano3, Atsushi J Nagano4,5
1Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo , Kashiwa, Chiba 277-8562, Japan.
Summary
Epigenetic changes in the pituitary gland, specifically chromatin accessibility, are vital for adaptation. Studying stickleback fish revealed genetic factors influencing these epigenetic differences, aiding local adaptation.
Area of Science:
- Evolutionary biology
- Genetics
- Epigenetics
Background:
- Epigenetic regulation, including chromatin accessibility, drives adaptation to diverse environments.
- Pituitary gland chromatin regulation is essential for life-history traits like growth, metabolism, and reproduction.
Purpose of the Study:
- Investigate the genetic architecture of epigenomic divergence using a parapatric pair of marine and stream stickleback ecotypes.
- Characterize distinct chromatin accessibility profiles in the pituitary gland between ecotypes.
Main Methods:
- Chromatin accessibility profiling in the pituitary gland of Gasterosteus aculeatus ecotypes.
- Chromatin quantitative trait loci (cQTL) mapping to identify genetic factors influencing chromatin accessibility.
- Comparative analyses of cQTL effect size, direction, and functional enrichment.
Main Results:
- Distinct chromatin accessibility profiles were identified between marine and stream stickleback ecotypes.
- Genome-wide cis- and trans-cQTLs were detected, indicating genetic control over chromatin accessibility.
- cis- and trans-cQTLs appear to contribute differently to epigenomic divergence.
Conclusions:
- Epigenomic divergence, influenced by both cis- and trans-cQTLs, is a key mechanism for local adaptation in sticklebacks.
- These findings highlight the role of epigenetics in the evolution of complex traits and adaptation to different environments.
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