Gene-expression signatures of Atlantic salmon's plastic life cycle

N. Aubin-Horth; B. H. Letcher; H.A. Hofmann

doi:10.1016/j.ygcen.2009.04.021

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Gene-expression signatures of Atlantic salmon's plastic life cycle

N. Aubin-Horth·B. H. Letcher·H.A. Hofmann

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Abstract

How genomic expression differs as a function of life history variation is largely unknown. Atlantic salmon exhibits extreme alternative life histories. We defined the gene-expression signatures of wild-caught salmon at two different life stages by comparing the brain expression profiles of mature sneaker males and immature males, and early migrants and late migrants. In addition to life-stage-specific signatures, we discovered a surprisingly large gene set that was differentially regulated-at similar magnitudes, yet in opposite direction-in both life history transitions. We suggest that this co-variation is not a consequence of many independent cellular and molecular switches in the same direction but rather represents the molecular equivalent of a physiological shift orchestrated by one or very few master regulators. ?? 2009 Elsevier Inc. All rights reserved.

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N. Aubin-Horth, B. H. Letcher, H.A. Hofmann. 2009. Gene-expression signatures of Atlantic salmon's plastic life cycle. https://doi.org/10.1016/j.ygcen.2009.04.021

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