title: Mode of cleavage of porcine big endothelin-1 by aspartic proteinases.
abstract: Cleavage sites of porcine big endothelin-1 (big ET-1, 1-39) by cathepsin D were examined and compared with those by other aspartic proteinases including pepsin. Cathepsin D cleaved not only the Trp21-Val22 bond, but also the Asp18-Ile19 bond of big ET-1[1-39]. The mature ET-1[1-21], generated by the cleavage between Trp21 and Val22, was subsequently degraded by removal of the C-terminal tripeptide (Ile19-Ile20-Trp21). On the other hand, pepsin cleaved the Trp21-Val22 bond of big ET-1[1-39] to produce ET-1[1-21], but did not degrade the generated ET-1[1-21]. These results indicate that aspartic proteinases such as cathepsin D and pepsin are capable of converting big ET-1[1-39] to ET-1[1-21], whereas the former proteinase is by no means specific for the Trp21-Val22 bond of big ET-1[1-39].
authors.affiliation: Department of Pharmacology, Osaka University of Pharmaceutical Sciences, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Takaoka
authors.forename: Y
authors.initials: Y
authors.lastname: Hukumori
authors.forename: K
authors.initials: K
authors.lastname: Shiragami
authors.forename: R
authors.initials: R
authors.lastname: Ikegawa
authors.forename: Y
authors.initials: Y
authors.lastname: Matsumura
authors.forename: S
authors.initials: S
authors.lastname: Morimoto
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D016282:Aspartic Acid Endopeptidases / Q000378:metabolism*; D002402:Cathepsin D / Q000378:metabolism; D019332:Endothelin-1; D016232:Endothelins / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D010434:Pepsin A / Q000378:metabolism; D011498:Protein Precursors / Q000378:metabolism*; D013552:Swine
chemical_list: D019332:Endothelin-1; D016232:Endothelins; D011498:Protein Precursors; D016282:Aspartic Acid Endopeptidases; D010434:Pepsin A; D002402:Cathepsin D