Please use this identifier to cite or link to this item: http://hdl.handle.net/2445/67156
Title: The olfactory transcriptome and progression of sexual maturation in homing chum salmon Oncorhynchus keta
Author: Palstra, Arjan P.
Chiba, Hiroaki
Dirks, Ron P.
Planas Vilarnau, Josep
Ueda, Hiroshi
Keywords: Expressió gènica
Orientació animal
Peixos marins
Gene expression
Animal orientation
Marine fishes
Issue Date: 23-Sep-2015
Publisher: Public Library of Science (PLoS)
Abstract: Reproductive homing migration of salmonids requires accurate interaction between the reception of external olfactory cues for navigation to the spawning grounds and the regulation of sexual maturation processes. This study aimed at providing insights into the hypothesized functional link between olfactory sensing of the spawning ground and final sexual maturation. We have therefore assessed the presence and expression levels of olfactory genes by RNA sequencing (RNAseq) of the olfactory rosettes in homing chum salmon Oncorhynchus keta Walbaum from the coastal sea to 75 km upstream the rivers at the prespawning ground. The progression of sexual maturation along the brain-pituitary-gonadal axis was assessed through determination of plasma steroid levels by time-resolved fluoroimmunoassays (TR-FIA), pituitary gonadotropin subunit expression and salmon gonadotropin-releasing hormone (sgnrh) expression in the brain by quantitative real-time PCR. RNAseq revealed the expression of 75 known and 27 unknown salmonid olfactory genes of which 13 genes were differentially expressed between fish from the pre-spawning area and from the coastal area, suggesting an important role of these genes in homing. A clear progression towards final maturation was characterised by higher plasma 17α,20β-dihydroxy-4-pregnen-3-one (DHP) levels, increased pituitary luteinizing hormone β subunit (lhβ)expression and sgnrh expression in the post brain, and lower plasma testosterone (T) and 17β-estradiol (E2) levels. Olfactomedins and ependymin are candidates among the differentially expressed genes that may connect olfactory reception to the expression of sgnrh to regulate final maturation.
Note: Reproducció del document publicat a: http://dx.doi.org/10.1371/journal. pone.0137404
It is part of: PLoS One, 2015, vol. 10, num. 9, p. e0137404-e0137404
Related resource: http://dx.doi.org/10.1371/journal. pone.0137404
URI: http://hdl.handle.net/2445/67156
ISSN: 1932-6203
Appears in Collections:Articles publicats en revistes (Biologia Cel·lular, Fisiologia i Immunologia)

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