Differential Regulation of c-Jun and JunD by Ubiquitin-Dependent Protein Degradation

• Published in: Biological Chemistry Vol. 377; no. 10; pp. 619 - 624
• Main Authors: Musti, Anna Maria, Treier, Mathias, Peverali, Fiorenzo A., Bohmann, Dirk
• Format: Journal Article
• Language: English
• Published: Berlin, New York Walter de Gruyter, Berlin / New York 01.10.1996; De Gruyter
• Subjects: 3T3 Cells; Amino Acid Sequence; Animals; Gene Expression Regulation; HeLa Cells; Humans; Hydrolysis; Mice; Molecular Sequence Data; Proto-Oncogene Proteins c-jun - genetics; Proto-Oncogene Proteins c-jun - metabolism; Recombinant Fusion Proteins - genetics; Recombinant Fusion Proteins - metabolism; Ubiquitins - metabolism
• ISSN: 0177-3593; 1431-6730; 1437-4315
• DOI: 10.1515/bchm3.1996.377.10.619

c-Jun and JunD are two closely related members of the Jun family of transcription factors which markedly differ in their biological functions. Whereas c-Jun behaves as a positive regulator of cell growth and may cause cell transformation when overexpressed, JunD antagonizes both of these effects. To better understand how the activities of c-Jun and JunD are controlled, we investigated how their stabilities within the cell are determined. We show that, in contrast to c-Jun which is degraded following multi ubiquitination, JunD is not efficiently ubiquitinated and exhibits a correspondingly longer half-life. Mutational analysis reveals that the determinant for the difference in ubiquitination resides in the NH2-terminal regions of the proteins which in c-Jun contains the delta-domain.