title: Proteinases participating in the processing and activation of prolegumain in primary cultured rat macrophages.
abstract: The mammalian legumain is a recently identified lysosomal cysteine proteinase belonging to the clan CD and homologous to plant legumain. This enzyme has the characteristic of specifically hydrolyzing peptide bonds after asparagine residues. As in the case of papain-type cysteine proteinases, legumain is synthesized as an inactive zymogen, and processed into a mature form localized in lysosomes. However, the mechanism of its activation remains unclear. In this study, we analyze which types of proteinases may participate in the processing of legumain in rat primary cultured macrophages using various proteinase inhibitors after 24 h treatment with Bafilomycin A1, a vacuolar ATPase inhibitor. The processing of legumain in macrophages was accomplished by papain-type cysteine proteinases other than cathepsin B.
authors.affiliation: Department of Biochemistry, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan.
authors.forename: Fabien
authors.initials: F
authors.lastname: Lecaille
authors.forename: Daisaku
authors.initials: D
authors.lastname: Muno
authors.forename: Eiki
authors.initials: E
authors.lastname: Kominami
authors.forename: Kazumi
authors.initials: K
authors.lastname: Ishidoh
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D003546:Cysteine Endopeptidases / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D004789:Enzyme Activation / Q000187:drug effects / Q000502:physiology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004792:Enzyme Precursors / Q000378:metabolism*; D018942:Macrolides / Q000494:pharmacology; D008264:Macrophages / Q000166:cytology / Q000201:enzymology*; D010206:Papain / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D025262:Vacuolar Proton-Translocating ATPases / Q000037:antagonists & inhibitors; D000099240:Asparaginyl Endopeptidase
chemical_list: D003546:Cysteine Endopeptidases; D015853:Cysteine Proteinase Inhibitors; D004791:Enzyme Inhibitors; D004792:Enzyme Precursors; D018942:Macrolides; D010206:Papain; D012333:RNA, Messenger; D025262:Vacuolar Proton-Translocating ATPases; D000099240:Asparaginyl Endopeptidase; C040929:bafilomycin A1