Calcium-binding protein which may have a role in calcium homeostasis (By similarity). Acts as a non-receptor guanine nucleotide exchange factor which binds to and activates guanine nucleotide-binding protein (G protein) alpha subunit GNAI3 (By similarity). . [Nesfatin-1]: Anorexigenic peptide, seems to play an important role in hypothalamic pathways regulating food intake and energy homeostasis, acting in a leptin-independent manner. May also exert hypertensive roles and modulate blood pressure through directly acting on peripheral arterial resistance. In intestinal epithelial cells, plays a role in the inhibition of hepatic glucose production via MC4R receptor leading to increased cyclic adenosine monophosphate (cAMP) levels and glucagon-like peptide 1 (GLP-1) secretion (PubMed:39562740). {ECO:0000250|UniProtKB:Q9JI85, ECO:0000269|PubMed:39562740}. This is the function of NUCB2 (nucleobindin 2, ENSG00000070081).