Distinct temporal patterns of Transaldolase 1 gene expression in future migratory and sedentary brown trout (Salmo trutta)

• Published in: Aquaculture
• Main Authors: Amstutz, Ursula, Giger, Thomas, Champigneulle, Alexis, Day, Philip J R, Largiadèr, Carlo R.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2006
• Subjects: Brown trout; Gene expression; Life-history; Real-time PCR; Salmo trutta; Transaldolase 1; Atlantic salmon
• Online Access: https://research.manchester.ac.uk/en/publications/33785d20-919b-4fcc-8717-854b6b6c75a6; https://doi.org/10.1016/j.aquaculture.2006.06.007

The occurrence of sedentary and migratory life-history forms is common in several salmonid fish species. A cDNA microarray study, investigating differences between these life-history forms at the level of the transcriptome, identified the transaldolase 1 gene (Taldo1) as being differently expressed in liver between sedentary and migratory brown trout populations just before the onset of migration. The aim of the study presented here was to gain further knowledge about the potential role of this gene during preparatory changes associated with the migratory life-history and the time of onset of this expression difference by investigating its expression levels in several juvenile age stages of sedentary and freshwater-migratory brown trout. A quantitative real-time PCR assay was established for the Taldo1 gene to measure its expression levels in liver samples of brown trout and Atlantic salmon. Taldo1 transcript levels were significantly lower in migratory brown trout and Atlantic salmon at the onset of migration compared to sedentary trout of the same age, confirming the results obtained by cDNA microarray technology. Comparison of Taldo1 expression patterns with changes in body condition factor led to the hypothesis that the observed lower levels of Taldo1 expression in migratory individuals are associated with the depletion of lipid stores during premigratory adaptations, potentially related to the smoltification process observed in anadromous salmonids, and a joint reduction in de novo lipid synthesis. Analysis of three juvenile stages of morphologically undifferentiated future migratory and sedentary brown trout revealed a significantly elevated expression level of the Taldo1 gene in future migratory trout compared to sedentary individuals three and a half month before the onset of migration, indicating an early signal potentially useful for predicting the future life-history of an individual. These results suggest that physiological differences between life-history forms might be measurable before ...