Gastrin-releasing peptide , also known as GRP, is an important regulatory molecule that has been implicated in a number of physiological and pathophysiological processes in humans.
The corresponding human gene has been identified. This gene encodes a member of the bombesin-like family of gastrin-releasing peptides. Its 148 amino acid (AA) preproprotein, following cleavage of a signal peptide, is further processed to produce either the 27 AA gastrin-releasing peptide or the 10 AA neuromedin C. These smaller peptides regulate numerous functions of the gastrointestinal and central nervous systems, including release of gastrointestinal hormones, smooth muscle cell contraction, and epithelial cell proliferation.
1. FUNCTION: GRP stimulates gastrin release as well as other gastrointestinal hormones. Operates as a negative feedback regulating fear and established a causal relationship between GRP- receptor gene expression, long-term potentiation, and amygdala- dependent memory for fear (By similarity).The gene identified by researchers at the Howard Hughes Medical Institute at Columbia University encodes a protein that inhibits the action of the fear-learning circuitry in the brain.
2. SUBCELLULAR LOCATION: Secreted.
3. ALTERNATIVE PRODUCTS: Event=Alternative splicing; Named isoforms=3; Name=1; IsoId=P07492-1; Sequence=Displayed; Name=2; IsoId=P07492-2; Sequence=VSP_000549; Name=3; IsoId=P07492-3; Sequence=VSP_000550;
4. SIMILARITY: Belongs to the bombesin/neuromedin-B/ranatensin family.