title: The many faces of Ras: recognition of small GTP-binding proteins.
abstract: The structures of over 30 complexes of Ras superfamily small GTP-binding proteins bound to diverse protein partners have been reported. Comparison of these complexes using the sequences of the small GTP-binding proteins to align the contact sites shows that virtually all surface positions make contacts with at least one partner protein. Rather than highlighting a single consensus binding site, these comparisons illustrate the remarkable diversity of contacts of Ras superfamily members. Here, a new analysis technique, the interface array, is introduced to quantify patterns of surface contacts. The interface array shows that small GTP-binding proteins are recognized in at least nine distinct ways. Remarkably, binding partners with similar functions, including those with distinct folds, recognize small GTP-binding proteins in similar ways. These classes of shared surface contacts support the occurrence of both divergent and convergent evolutionary processes and suggest that specific effector functions require particular protein-protein contacts.
authors.affiliation: Dept of Molecular and Cellular Biology, 229 Stanley Hall #3206, University of California, Berkeley, CA 94720-3206, USA. korbett@uclink4.berkeley.edu
authors.forename: K D
authors.initials: KD
authors.lastname: Corbett
authors.forename: T
authors.initials: T
authors.lastname: Alber
mesh_terms: D000818:Animals; D001665:Binding Sites; D016000:Cluster Analysis; D016384:Consensus Sequence; D006801:Humans; D046911:Macromolecular Substances; D008958:Models, Molecular; D020559:Monomeric GTP-Binding Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D011487:Protein Conformation; D025941:Protein Interaction Mapping; D016283:Proto-Oncogene Proteins p21(ras) / Q000737:chemistry / Q000378:metabolism; D016415:Sequence Alignment
chemical_list: D046911:Macromolecular Substances; C501009:HRAS protein, human; D020559:Monomeric GTP-Binding Proteins; D016283:Proto-Oncogene Proteins p21(ras)