Plays a role in the regulation of food intake and body weight and in reproduction. May also play a role as a central modulator of cardiovascular and renal function and nociception (By similarity). Brain administration of the peptide inhibits food consumption. May function as a satiety factor for feeding control. Involved in the negative regulation of the reproductive axis by inhibiting luteinizing hormone secretion from pituitary cells (PubMed:23715729, PubMed:23623870). Expressed in the anterior hypothalamus, ventromedial thalamic nucleus and medial longitudinal fasciculus of the brain (at protein level). Widely expressed. Expressed predominantly in the spleen, kidney, liver and testis. Expressed in olfactory bulb, pituitary, telencephalon, diencephalons, spinal cord, optic tectum, cerebellum and hypothalamus of the brain. Up-regulated during female seasonal sexual maturation and after ovariectomy. Up-regulated by food intake in brain areas involved in appetit control. Amidated and nonamidated form of Spexin-1 had similar effects on food intake/feeding behaviors. Belongs to the spexin family.