Early exposure to chronic hypoxia induces short- and long-term regulation of hemoglobin gene expression in European sea bass (Dicentrarchus labrax)

Type Article
Date 2017-09
Language English
Author(s) Cadiz Laura1, Servili Arianna1, Quazuguel PatrickORCID1, Madec Lauriane1, Zambonino-Infante Jose-LuisORCID1, Mazurais DavidORCID1
Affiliation(s) 1 : IFREMER, Ctr Bretagne, Unite Physiol Fonct Organismes Marins, LEMAR,UMR 6539, F-29280 Plouzane, France.
Source Journal Of Experimental Biology (0022-0949) (Company Of Biologists Ltd), 2017-09 , Vol. 220 , N. 17 , P. 3119-3126
DOI 10.1242/jeb.160713
WOS© Times Cited 9
Keyword(s) Hypoxia, Hemoglobin, Early exposure, European sea bass
Abstract

European sea bass (Dicentrarchus labrax) inhabits coastal waters and may be exposed to hypoxia at different life stages, requiring physiological and behavioral adaptation. In the present study, we attempted to determine whether regulation of hemoglobin (Hb) gene expression plays a role in the physiological response to chronic moderate hypoxia in whole larvae and hematopoietic tissues (head kidney and spleen) of juveniles. We also tested the hypothesis that hypoxia exposure at the larval stage could induce a long-term effect on the regulation of Hb gene expression. For this purpose, D. labrax were exposed to a non-lethal hypoxic condition (40% air saturation) at the larval stage from 28 to 50 days post-hatching (dph) and/or at the juvenile stage from 196 to 296 dph. Data obtained from larvae indicate that hypoxia induced a subtype-specific regulation of Hb gene expression, with a significant decrease of MN-Hba3, MN-Hb beta 4 and MN-Hb beta 5 and increase of MN-Hb alpha 2, LA-Hb alpha 1 and LA-Hb beta 1 transcript levels. Hypoxia did not induce regulation of Hb gene expression in juveniles, except in the head kidney for those that experienced hypoxia at the larval stage. The latter exhibited a significant hypoxia-induced stimulation of MN-Hba2, LA-Hba1 and LA-Hb beta 1 gene expression, associated with stimulation of the PHD-3 gene involved in the hypoxia-inducible factor oxygen-sensing pathway. We conclude that subtype-and stage-specific regulation of Hb gene expression plays a role in the physiological response of D. labrax to cope with hypoxia and that early exposure to low oxygen concentration has a long-term effect on this response.

Full Text
File Pages Size Access
Publisher's official version + Supplementary information 11 816 KB Open access
Top of the page

How to cite 

Cadiz Laura, Servili Arianna, Quazuguel Patrick, Madec Lauriane, Zambonino-Infante Jose-Luis, Mazurais David (2017). Early exposure to chronic hypoxia induces short- and long-term regulation of hemoglobin gene expression in European sea bass (Dicentrarchus labrax). Journal Of Experimental Biology, 220(17), 3119-3126. Publisher's official version : https://doi.org/10.1242/jeb.160713 , Open Access version : https://archimer.ifremer.fr/doc/00399/51039/