Somatotropic axis genes are expressed before pituitary onset during zebrafish and sea bass development
|Author(s)||Besseau Laurence1, 2, Fuentes Michael1, 2, Sauzet Sandrine1, 2, Beauchaud Marilyn3, Chatain Beatrice4, Coves Denis4, Boeuf Gilles1, 2, 5, Falcon Jack1, 2|
|Affiliation(s)||1 : Univ Paris 06, Lab Arago, F-66650 Banyuls Sur Mer, France.
2 : CNRS UMR 7232, F-66650 Banyuls Sur Mer, France.
3 : Univ Lyon St Etienne, Equipe Neuroethol Sensorielle, ENES CNPS, CNRS UMR 8195, F-42023 St Etienne 2, France.
4 : Stn Ifremer Palavas, UMR Intrepid 110, F-34250 Palavas Les Flots, France.
5 : MNHN, F-75005 Paris, France.
|Source||General And Comparative Endocrinology (0016-6480) (Academic Press Inc Elsevier Science), 2013-12 , Vol. 194 , P. 133-141|
|WOS© Times Cited||13|
|Keyword(s)||Growth hormone GH, Insulin-like growth factor-1 IGF-1, Pituitary, Development, Zebrafish, Sea bass|
|Abstract||The somatotropic axis, or growth hormone-insulin-like growth factor-1 (GH-IGF-1) axis, of fish is involved in numerous physiological process including regulation of ionic and osmotic balance, lipid, carbohydrate and protein metabolism, growth, reproduction, immune function and behavior. It is thought that GH plays a role in fish development but conflicting results have been obtained concerning the ontogeny of the somatotropic axis. Here we investigated the developmental expression of GH, GH-receptor (GHR) and IGF-1 genes and of a GH-like protein from fertilization until early stages of larval development in two Teleosts species, Danio rerio and Dicentrarchus labrax, by PCR, in situ hybridization and Western blotting. GH, GHR and IGF-1 mRNA were present in unfertilized eggs and at all stages of embryonic development, all three displaying a similar distribution in the two species. First located in the whole embryo (until 12 hpf in zebrafish and 76 hpf in sea bass), the mRNAs appeared then distributed in the head and tail, from where they disappeared progressively to concentrate in the forming pituitary gland. Proteins immunoreactive with a specific sea bass anti-GH antibody were also detected at all stages in this species. Differences in intensity and number of bands suggest that protein processing varies from early to later stages of development. The data show that all actors of the somatotropic axis are present from fertilization in these two species, suggesting they plays a role in early development, perhaps in an autocrine/paracrine mode as all three elements displayed a similar distribution at each stage investigated.|