title: Specification of SUMO1- and SUMO2-interacting motifs.
abstract: SUMO proteins are ubiquitin-related modifiers implicated in the regulation of gene transcription, cell cycle, DNA repair, and protein localization. The molecular mechanisms by which the sumoylation of target proteins regulates diverse cellular functions remain poorly understood. Here we report isolation and characterization of SUMO1- and SUMO2-binding motifs. Using yeast two-hybrid system, bioinformatics, and NMR spectroscopy we define a common SUMO-interacting motif (SIM) and map its binding surfaces on SUMO1 and SUMO2. This motif forms a beta-strand that could bind in parallel or antiparallel orientation to the beta2-strand of SUMO due to the environment of the hydrophobic core. A negative charge imposed by a stretch of neighboring acidic amino acids and/or phosphorylated serine residues determines its specificity in binding to distinct SUMO paralogues and can modulate the spatial orientation of SUMO-SIM interactions.
authors.affiliation: Institute for Biochemistry II, Goethe University Medical School, Theodor-Stern-Kai 7, 60590 Frankfurt, Germany.
authors.forename: Christina-Maria
authors.initials: CM
authors.lastname: Hecker
authors.forename: Matthias
authors.initials: M
authors.lastname: Rabiller
authors.forename: Kaisa
authors.initials: K
authors.lastname: Haglund
authors.forename: Peter
authors.initials: P
authors.lastname: Bayer
authors.forename: Ivan
authors.initials: I
authors.lastname: Dikic
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D001483:Base Sequence; D001665:Binding Sites; D002460:Cell Line; D017931:DNA Primers; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D019906:Nuclear Magnetic Resonance, Biomolecular; D010766:Phosphorylation; D010957:Plasmids; D025842:SUMO-1 Protein; D017386:Sequence Homology, Amino Acid; D025841:Small Ubiquitin-Related Modifier Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D020798:Two-Hybrid System Techniques
chemical_list: D017931:DNA Primers; D025842:SUMO-1 Protein; C495501:SUMO1 protein, human; C117909:SUMO2 protein, human; D025841:Small Ubiquitin-Related Modifier Proteins