title: Protein interactions in the sumoylation cascade: lessons from X-ray structures.
abstract: Sumoylation is a multi-step protein modification reaction in which SUMO (small ubiquitin-like modifier) proteins are covalently attached to lysine residues of substrate proteins. Here, we compare the sequences and structures of modifiers and enzymes involved in sumoylation with those of the related ubiquitination and neddylation cascades. By using available structural data on modifier/enzyme/substrate interactions, we discuss and model sumoylation complexes that include SUMO-1 and the E1 and E2 enzymes Aos1-uba2 and ubc9, or SUMO-1 and E2 together with the E3 ligase RanBP2 and its substrate RanGAP1. Their comparison provides insight into the protein interactions underlying sumoylation, and suggests how SUMO proteins may be translocated between enzymes during the various steps of the protein modification reaction.
authors.affiliation: Department of Neurochemistry, Max-Planck-Institute for Brain Research, Deutschordenstrasse 46, Frankfurt, Germany.
authors.forename: Zhongshu
authors.initials: Z
authors.lastname: Tang
authors.forename: Christina M
authors.initials: CM
authors.lastname: Hecker
authors.forename: Astrid
authors.initials: A
authors.lastname: Scheschonka
authors.forename: Heinrich
authors.initials: H
authors.lastname: Betz
mesh_terms: D000595:Amino Acid Sequence; D018360:Crystallography, X-Ray; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D050828:Protein Inhibitors of Activated STAT / Q000737:chemistry; D054730:Protein Interaction Domains and Motifs; D011499:Protein Processing, Post-Translational; D025841:Small Ubiquitin-Related Modifier Proteins / Q000737:chemistry* / Q000378:metabolism*; D044764:Ubiquitin-Activating Enzymes / Q000737:chemistry; D044763:Ubiquitin-Conjugating Enzymes / Q000737:chemistry; D043743:Ubiquitin-Protein Ligase Complexes / Q000737:chemistry*; D044767:Ubiquitin-Protein Ligases / Q000737:chemistry
chemical_list: D050828:Protein Inhibitors of Activated STAT; D025841:Small Ubiquitin-Related Modifier Proteins; D044763:Ubiquitin-Conjugating Enzymes; D043743:Ubiquitin-Protein Ligase Complexes; D044767:Ubiquitin-Protein Ligases; D044764:Ubiquitin-Activating Enzymes