Proteolytic cleavage of protein kinase Cμ upon induction of apoptosis in U937 cells

• Verfasst von: Häussermann, Sabine [VerfasserIn]
• Verfasst von: Kittstein, Walter [VerfasserIn]
• Verfasst von: Rincke, Gabriele [VerfasserIn]
• Verfasst von: Johannes, Franz-Josef [VerfasserIn]
• Verfasst von: Marks, Friedrich [VerfasserIn]
• Verfasst von: Gschwendt, Michael [VerfasserIn]
• Titel: Proteolytic cleavage of protein kinase Cμ upon induction of apoptosis in U937 cells
• Titelzusatz: Identification of the cleavage site and characterization of the fragment
• Verf.angabe: Sabine Häussermann, Walter Kittstein, Gabriele Rincke, Franz-Josef Johannes, Friedrich Marks, Michael Gschwendt
• E-Jahr: 1999
• Jahr: 30 November 1999
• Umfang: 5 S.
• Fussnoten: Gesehen am 22.04.2021
• Titel Quelle: Enthalten in: Vereinigung der Europäischen Biochemischen GesellschaftenFEBS letters
• Ort Quelle: Chichester : Wiley, 1968
• Jahr Quelle: 1999
• Band/Heft Quelle: 462(1999), 3, Seite 442-446
• ISSN Quelle: 1873-3468
• DOI: doi:10.1016/S0014-5793(99)01577-X
• Datenträger: Online-Ressource
• Sprache: eng
• Sach-SW: Apoptosis
• Sach-SW: Caspase-3
• Sach-SW: Caspase-3 inhibitor
• Sach-SW: Cleavage site
• Sach-SW: Protein kinase Cμ
• Sach-SW: Proteolytic fragment
• K10plus-PPN: 1755734301

Abstract

Treatment of U937 cells with various apoptosis-inducing agents, such as TNFα and β-D-arabinofuranosylcytosine (ara-C) alone or in combination with the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA), bryostatin 1 or cycloheximide, causes proteolytic cleavage of protein kinase Cμ (PKCμ) between the regulatory and catalytic domain, generating a 62 kDa catalytic fragment of the kinase. The formation of this fragment is effectively suppressed by the caspase-3 inhibitor Z-DEVD-FMK. In accordance with these in vivo data, treatment of recombinant PKCμ with caspase-3 in vitro results also in the generation of a 62 kDa fragment (p62). Treatment of several aspartic acid to alanine mutants of PKCμ with caspase-3 resulted in an unexpected finding. PKCμ is not cleaved at one of the typical cleavage sites containing the motif DXXD but at the atypical site CQND378/S379. The respective fragment (amino acids 379-912) was expressed in bacteria as a GST fusion protein (GST-p62) and partially purified. In contrast to the intact kinase, the fragment does not respond to the activating cofactors TPA and phosphatidylserine and is thus unable to phosphorylate substrates effectively.