Aquaculture Reports (Apr 2024)
Identification and functional characterization of Nicol1: A novel peptide regulating feeding in pompano (Trachinotus ovatus)
Abstract
NELL2 interacting cell ontogeny regulator 1 (Nicol1) is a novel peptide that has not been identified in fish. To ascertain the neuroendocrine function of Nicol1 in pompano (Trachinotus ovatus), its cDNA sequence was cloned and analyzed. The result showed that Nicol1 has a putative maturation peptide named Nicol1–17, and its amino acid sequence is highly conserved in teleost fishes. Tissue distribution analysis showed that nicol1 was highly expressed in the brain, pituitary, and heart of males, while highly expressed in the brain, pituitary, and ovary of females. Quantitative real-time PCR (qPCR) analysis showed that nicol1 was significantly upregulated in the hypothalamus after 2 d and 7 d fasting, but its expression returned to the level of the control group level after refeeding. In addition, in vivo or in vitro experiments showed that Nicol1–17 peptide treatment significantly increased the mRNA expression of agouti gene-related protein (agrp), neuropeptide y (npy), growth hormone-releasing hormone receptor (ghrhr) mRNA in the hypothalamus, and growth hormone (gh) and thyroid stimulating hormone beta (tshβ) mRNA in the pituitary. These genes are closely related to feeding and growth in teleost fishes. Our results suggest that Nicol1 plays a crucial role in regulating feeding and may also be involved in growth regulation in pompano.