Definition
ChEBI: A member of the class of mastopyrans that is a 14-amino acid polypeptide comprising isoleucyl, asparaginyl, leucyl, lysyl, alanyl, leucyl, alanyl, alanyl, leucyl, alanyl, lysyl, lysyl, isoleucyl, and leucinamide residues coupled in sequence. It is the majo
active component of the venom of the vespid wasp, Vespula lewisii and causes degranulation of mast cells.
General Description
Mastoparan is a cationic, amphiphilic, tetradecapeptide amide. It is composed of the restricted amino acid and the repeated sequence. This protein is a nonspecific secretagogue isolated from venom of wasp.
Biochem/physiol Actions
Mastoparan effectively stimulates exocytosis from diverse mammalian cells. The encoded protein facilitates the secretion of histamine from mast cells, serotonin from platelets, catecholamines from chromaffin cells and prolactin from the anterior pituitary. In addition, it is also involved in activation of Phospholipase A2 and phosphoinositides (Pl) break down. Mastoparan functions as an inhibitor for calmodulin-stimulated phosphodiesterase. Mastoparan helps in mitochondrial permeability transition by enhancing an apparent bimodal mechanism of action.
