title: Regional variation of gene regulation associated with storage lipid metabolism in American glass eels (Anguilla rostrata).
abstract: Variation in gene regulation may be involved in the differences observed for life history traits within species. American eel (Anguilla rostrata) is well known to harbor distinct ecotypes within a single panmictic population. We examined the expression of genes involved in the regulation of appetite as well as lipid and glycogen among glass eels migrating to different locations on the Canadian east coast and captured at two different periods of upstream migration. Gene expression levels of three reference and five candidate genes were analyzed by real-time PCR with Taqman probes in recently captured wild glass eels. All gene transcripts were detected in glass eels. Of the five candidate genes, bile salt activated and triacylglycerol lipases were respectively 7.65 and 3.25 times more expressed in glass eels from the St. Lawrence estuary than in those from Nova Scotia, and there was no effect related to the two-week difference in capture date. These two genes explained 82.41% of the dissimilarity between the two rivers. In contrast, glycogen phosphorylase, ghrelin, and leptin receptor genes showed no significant differences in gene transcription. These results confirmed at the molecular level an observation that was recently made at the phenotypic level that glass eels from the St. Lawrence estuary have a greater capacity to use lipid reserves to sustain their metabolic needs. These observations add to the body of evidence supporting the hypothesis that regional phenotypic variation observed in American eel is determined early in life and that part of this variation is likely under genetic control.
authors.affiliation: Institut des sciences de la mer de Rimouski, Université du Québec à Rimouski, 310 Allée des Ursulines, Rimouski, Québec G5L 3A1, Canada. Electronic address: melanie.gaillard@uqar.ca.
authors.forename: Mélanie
authors.initials: M
authors.lastname: Gaillard
authors.affiliation: Institut de Biologie Intégrative et des Systèmes, Département de biologie, Université Laval, 1030 avenue de la Médecine, Québec, Québec G1V 0A6, Canada. Electronic address: scottapavey@gmail.com.
authors.forename: Scott A
authors.initials: SA
authors.lastname: Pavey
authors.affiliation: Institut de Biologie Intégrative et des Systèmes, Département de biologie, Université Laval, 1030 avenue de la Médecine, Québec, Québec G1V 0A6, Canada. Electronic address: caocote@hotmail.com.
authors.forename: Caroline L
authors.initials: CL
authors.lastname: Côté
authors.affiliation: Institut des sciences de la mer de Rimouski, Université du Québec à Rimouski, 310 Allée des Ursulines, Rimouski, Québec G5L 3A1, Canada. Electronic address: rejean_tremblay@uqar.ca.
authors.forename: Réjean
authors.initials: R
authors.lastname: Tremblay
authors.affiliation: Institut de Biologie Intégrative et des Systèmes, Département de biologie, Université Laval, 1030 avenue de la Médecine, Québec, Québec G1V 0A6, Canada. Electronic address: Louis.Bernatchez@bio.ulaval.ca.
authors.forename: Louis
authors.initials: L
authors.lastname: Bernatchez
authors.affiliation: Institut des sciences de la mer de Rimouski, Université du Québec à Rimouski, 310 Allée des Ursulines, Rimouski, Québec G5L 3A1, Canada. Electronic address: celine_audet@uqar.ca.
authors.forename: Céline
authors.initials: C
authors.lastname: Audet
mesh_terms: D000811:Anguilla / Q000235:genetics* / Q000378:metabolism*; D000818:Animals; D017753:Ecosystem; D063366:Estuaries; D029941:Fish Proteins / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation; D006003:Glycogen / Q000235:genetics / Q000378:metabolism; D008049:Lipase / Q000235:genetics; D050356:Lipid Metabolism / Q000235:genetics*; D009674:Nova Scotia; D045483:Rivers
chemical_list: D029941:Fish Proteins; D006003:Glycogen; D008049:Lipase
keywords: Ecotypes; Ghrelin; Glycogen phosphorylase; Leptin receptor; Lipase; Transcriptomics; mRNA expression