3ryf
From Proteopedia
GTP-Tubulin: RB3 Stathmin-like domain complex
Structural highlights
FunctionD0VWZ0_SHEEP Tubulin is the major constituent of microtubules. It binds two moles of GTP, one at an exchangeable site on the beta chain and one at a non-exchangeable site on the alpha chain (By similarity).[RuleBase:RU003505][SAAS:SAAS023123_004_019801] Publication Abstract from PubMedTubulin alternates between a soluble curved structure and a microtubule straight conformation. GTP binding to alphabeta-tubulin is required for microtubule assembly, but whether this triggers conversion into a straighter structure is still debated. This is due, at least in part, to the lack of structural data for GTP-tubulin before assembly. Here, we report atomic-resolution crystal structures of soluble tubulin in the GDP and GTP nucleotide states in a complex with a stathmin-like domain. The structures differ locally in the neighborhood of the nucleotide. A loop movement in GTP-bound tubulin favors its recruitment to the ends of growing microtubules and facilitates its curved-to-straight transition, but this conversion has not proceeded yet. The data therefore argue for the conformational change toward the straight structure occurring as microtubule-specific contacts are established. They also suggest a model for the way the tubulin structure is modified in relation to microtubule assembly. The determinants that govern microtubule assembly from the atomic structure of GTP-tubulin.,Nawrotek A, Knossow M, Gigant B J Mol Biol. 2011 Sep 9;412(1):35-42. Epub 2011 Jul 23. PMID:21787788[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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