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Updated: Aug 11, 2026

Preparation of Segmented Microtubules to Study Motions Driven by the Disassembling Microtubule Ends
Published on: March 15, 2014
Localization of an exchangeable GTP binding site at the plus end of microtubules
1Department of Pharmacology, University of California, San Francisco 94143-0450.
Abstract:
Microtubule polarity arises from the head-to-tail orientation of alpha-beta tubulin heterodimers in the microtubule lattice. The identity of the polypeptide at each end of the microtubule is unknown, but structural models predict that the beta-tubulin end contains an exchangeable guanosine triphosphate (GTP) binding site. When GTP-coated fluorescent beads were incubated with microtubules, they bound specifically to plus ends, suggesting that tubulin is oriented in microtubules with beta-tubulin toward the plus end.
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