Original Research ARTICLE
Egr-1 induction provides a genetic response to food aversion in zebrafish
- INSERM U 1024, CNRS UMR 8197, Ecole Normale Supérieure, IBENS, Developmental Biology, Paris, France
As soon as zebrafish larvae start eating, they exhibit a marked aversion for bitter and acidic substances, as revealed by a consumption assay, in which fluorescent Tetrahymena serve as a feeding basis, to which various stimuli can be added. Bitter and acidic substances elicited an increase in mRNA accumulation of the immediate-early response gene egr-1, as revealed by in situ hybridization. Conversely, chemostimulants that did not induce aversion did not induce egr-1 response. Maximum labeling was observed in cells located in the oropharyngeal cavity and on the gill rakers. Gustatory areas of the brain were also labeled. Interestingly, when bitter tastants were repeatedly associated with food reward, zebrafish juveniles learned to ingest food in the presence of the bitter compound. After habituation, the acquisition of acceptance for bitterness was accompanied by a loss of egr-1 labeling. Altogether, our data indicate that egr-1 participates specifically in food aversion. The existence of reward-coupled changes in taste sensitivity in humans suggests that our results are relevant to situations in humans.
Keywords: zebrafish, egr-1, bitterness, taste aversion, consumption assay
Citation: Boyer B, Ernest S and Rosa F (2013) Egr-1 induction provides a genetic response to food aversion in zebrafish. Front. Behav. Neurosci. 7:51. doi: 10.3389/fnbeh.2013.00051
Received: 25 March 2013; Paper pending published: 11 April 2013;
Accepted: 06 May 2013; Published online: 22 May 2013.
Edited by:Julietta U. Frey, Georgia Regents University, USA
Reviewed by:Osborne F. Almeida, Max Planck Institute of Psychiatry, Germany
Allan V. Kalueff, Tulane University, USA
Copyright © 2013 Boyer, Ernest and Rosa. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in other forums, provided the original authors and source are credited and subject to any copyright notices concerning any third-party graphics etc.
*Correspondence: Brigitte Boyer, INSERM U 1024, CNRS UMR 8197, Ecole Normale Supérieure, IBENS, 46 rue d'Ulm 75005, Paris, France. e-mail: firstname.lastname@example.org