Dataset Information

Differential expression of olfactory genes in Atlantic salmon (Salmo salar) during the parr-smolt transformation.

ABSTRACT: The anadromous salmon life cycle includes two migratory events, downstream smolt migration and adult homing migration, during which they must navigate with high precision. During homing migration, olfactory cues are used for navigation in coastal and freshwater areas, and studies have suggested that the parr-smolt transformation has a sensitive period for imprinting. Accordingly, we hypothesized that there would be significant changes in gene expression in the olfactory epithelium specifically related to smoltification and sampled olfactory rosettes from hatchery-reared upper growth modal juvenile Atlantic salmon at 3-week intervals from January to June, using lower growth modal nonsmolting siblings as controls. A suite of olfactory receptors and receptor-specific proteins involved in functional aspects of olfaction and peripheral odor memorization was analyzed by qPCR. Gene expression in juveniles was compared with mature adult salmon of the same genetic strain caught in the river Gudenaa. All mRNAs displayed significant variation over time in both modal groups. Furthermore, five receptor genes (olfc13.1, olfc15.1, sorb, ora2, and asor1) and four olfactory-specific genes (soig, ependymin, gst, and omp2) were differentially regulated between modal groups, suggesting altered olfactory function during smoltification. Several genes were differentially regulated in mature salmon compared with juveniles, suggesting that homing and odor recollection involve a different set of genes than during imprinting. Thyroid hormone receptors thr? and thr? mRNAs were elevated during smolting, suggesting increased sensitivity to thyroid hormones. Treatment of presmolts with triiodothyronine in vivo and ex vivo had, however, only subtle effects on the investigated olfactory targets, questioning the hypothesis that thyroid hormones directly regulate gene expression in the olfactory epithelium.

SUBMITTER: Madsen SS

PROVIDER: S-EPMC6953650 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Differential expression of olfactory genes in Atlantic salmon (<i>Salmo salar</i>) during the parr-smolt transformation.

Madsen Steffen S SS Winther Sara S T SST Bollinger Rebecca J RJ Steiner Ulrich U Larsen Martin H MH

Ecology and evolution 20191128 24

The anadromous salmon life cycle includes two migratory events, downstream smolt migration and adult homing migration, during which they must navigate with high precision. During homing migration, olfactory cues are used for navigation in coastal and freshwater areas, and studies have suggested that the parr<b>-</b>smolt transformation has a sensitive period for imprinting. Accordingly, we hypothesized that there would be significant changes in gene expression in the olfactory epithelium specifi ...[more]

PMID: 31938505

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Dataset Information

Differential expression of olfactory genes in Atlantic salmon (Salmo salar) during the parr-smolt transformation.

Publications

Differential expression of olfactory genes in Atlantic salmon (<i>Salmo salar</i>) during the parr-smolt transformation.

Similar Datasets

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