Stu2p/XMAP215/Dis1 family proteins are evolutionarily conserved regulatory factors that use alphabeta-tubulin-interacting tumor overexpressed gene (TOG) domains to catalyze fast microtubule growth. Catalysis requires that these polymerases discriminate between unpolymerized and polymerized forms of alphabeta-tubulin, but the mechanism by which they do so has remained unclear. Here, we report the structure of the TOG1 domain from Stu2p bound to yeast alphabeta-tubulin. TOG1 binds alphabeta-tubulin in a way that excludes equivalent binding of a second TOG domain. Furthermore, TOG1 preferentially binds a curved conformation of alphabeta-tubulin that cannot be incorporated into microtubules, contacting alpha- and beta-tubulin surfaces that do not participate in microtubule assembly. Conformation-selective interactions with alphabeta-tubulin explain how TOG-containing polymerases discriminate between unpolymerized and polymerized forms of alphabeta-tubulin and how they selectively recognize the growing end of the microtubule.
|Evidence ID||Analyze ID||Interactor||Interactor Systematic Name||Interactor||Interactor Systematic Name||Type||Assay||Annotation||Action||Modification||Phenotype||Source||Reference||Note|
|Evidence ID||Analyze ID||Gene||Gene Systematic Name||Gene Ontology Term||Gene Ontology Term ID||Qualifier||Aspect||Method||Evidence||Source||Assigned On||Reference||Annotation Extension|
|Evidence ID||Analyze ID||Gene||Gene Systematic Name||Phenotype||Experiment Type||Experiment Type Category||Mutant Information||Strain Background||Chemical||Details||Reference|
|Evidence ID||Analyze ID||Regulator||Regulator Systematic Name||Target||Target Systematic Name||Experiment||Conditions||Strain||Source||Reference|