FOXO1A promotes neuropeptide FF transcription subsequently regulating the expression of feeding-related genes in spotted sea bass (Lateolabrax maculatus)

FOXOs belong to the forkhead transcription factor superfamily, several of which are suggested to be involved in the control of food intake. Previously, we proved that the neuropeptide FF (NPFF) peptide was involved in feeding regulation in spotted sea bass. In the present study, seven members of the foxo family were identified in the whole genome of spotted sea bass. The distributions of these genes in different tissues were analyzed by qRT-PCR. Variations in the foxola and npff expression profiles during short-term starvation showed similar expression patterns. The colocalization of foxola and npff in the telencephalon, hypothalamus, stomach and intestine further provided evidence that foxola may act directly to promote the transcription of npff Thirteen predicted FOXO1 binding sites were found in the 5' upstream region of npff Luciferase assay results showed that FOXO1A was able to activate npff transcriptional responses by directly binding DNA response elements, and the key regulatory areas and sites of FOXO1A on the npff promoter were confirmed by deletion and site-directed mutagenesis analyses. These findings may help to elucidate the role of FOXO1 in the regulation of feeding processes in teleosts.