SUMO-1 Conjugation in Vivo Requires Both a Consensus Modification Motif and Nuclear Targeting

• Published in: The Journal of biological chemistry Vol. 276; no. 16; pp. 12654 - 12659
• Main Authors: Rodriguez, M S, Dargemont, C, Hay, R T
• Format: Journal Article
• Language: English
• Published: United States American Society for Biochemistry and Molecular Biology 20.04.2001
• Subjects: Amino Acid Sequence; Carrier Proteins - chemistry; Carrier Proteins - metabolism; Cell Nucleus - metabolism; Consensus Sequence; DNA-Binding Proteins - chemistry; DNA-Binding Proteins - metabolism; GTPase-Activating Proteins - chemistry; GTPase-Activating Proteins - metabolism; HeLa Cells; Humans; I-kappa B Proteins; NF-KappaB Inhibitor alpha; Recombinant Fusion Proteins - chemistry; Recombinant Fusion Proteins - metabolism; Sequence Alignment; Sequence Homology, Amino Acid; SUMO-1 Protein; Transfection; Tumor Suppressor Protein p53 - chemistry; Tumor Suppressor Protein p53 - metabolism; Ubiquitins - chemistry; Ubiquitins - genetics; Ubiquitins - metabolism
• DOI: 10.1074/jbc.M009476200
• ISSN: 0021-9258

SUMO-1 is a small ubiquitin-related modifier that is covalently linked to many cellular protein targets. Proteins modified by SUMO-1 and the SUMO-1-activating and -conjugating enzymes are located predominantly in the nucleus. Here we define a transferable sequence containing the ΨK X E motif, where Ψ represents a large hydrophobic amino acid, that confers the ability to be SUMO-1-modified on proteins to which it is linked. Whereas addition of short sequences from p53 and IκBα, containing the ΨK X E motif, to a carrier protein is sufficient for modification in vitro , modification in vivo requires the additional presence of a nuclear localization signal. Thus, protein substrates must be targeted to the nucleus to undergo SUMO-1 conjugation.