title: Neutral endopeptidase neprilysin is copurified with Na,K-ATPase from rabbit outer medulla and hydrolyzes its α-subunit.
abstract: Preparations of Na,K-ATPase from outer medulla of rabbit kidney purified in accordance with the method of P. L. Jorgensen were shown to contain as admixture a protease that moves with α-subunit (~100 kDa) as a single protein band during one-dimensional SDS-PAGE. The electro-elution of proteins of this band from polyacrylamide gel results in the appearance of two protein fragments (~67 and 55 kDa) that are stained with polyclonal antibodies against Na,K-ATPase α-subunit. Liquid chromatography/tandem mass spectrometry (LC/MS/MS) analysis showed that the neutral membrane-bound endopeptidase neprilysin is located in one protein band together with the Na,K-ATPase α-subunit. Addition of thiorphan, a specific inhibitor of neutral endopeptidase, eliminates proteolysis of the α-subunit. The data demonstrate that Na,K-ATPase α-subunit may be a natural target for neprilysin.
authors.affiliation: Department of Biochemistry, Lomonosov Moscow State University, Russia.
authors.forename: M A
authors.initials: MA
authors.lastname: Groubman
authors.forename: Y V
authors.initials: YV
authors.lastname: Kamanina
authors.forename: I Iu
authors.initials: IIu
authors.lastname: Petrushanko
authors.forename: A M
authors.initials: AM
authors.lastname: Rubtsov
authors.forename: O D
authors.initials: OD
authors.lastname: Lopina
mesh_terms: D000818:Animals; D006868:Hydrolysis; D007679:Kidney Medulla / Q000201:enzymology*; D015260:Neprilysin / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D021122:Protein Subunits / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D011817:Rabbits; D000254:Sodium-Potassium-Exchanging ATPase / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism
chemical_list: D021122:Protein Subunits; D015260:Neprilysin; D000254:Sodium-Potassium-Exchanging ATPase