title: Kinetics of GTP hydrolysis during the assembly of chick brain MAP2-tubulin microtubule protein.
abstract: The kinetics of GTP hydrolysis during microtubule assembly have been examined using chick brain MAP2-tubulin microtubule protein in a NaCl-supplemented buffer. The elongating microtubules terminate in a 'GTP cap', since the kinetics of GTP hydrolysis are slower than those of subunit addition. GTP hydrolysis is (a) stoichiometric, (b) occurs as a vectorial wave as the initial rate of hydrolysis is proportional to the molar concentration of microtubule ends and not to the initial rate of subunit addition, and (c) either does not occur, or occurs only at a much lower rate, in the terminal subunits.
authors.affiliation: Biophysics Section, Blackett Laboratory, Imperial College of Science, Technology and Medicine, London, U.K.
authors.forename: R G
authors.initials: RG
authors.lastname: Burns
mesh_terms: D000818:Animals; D001921:Brain / Q000378:metabolism*; D002645:Chickens; D006160:Guanosine Triphosphate / Q000378:metabolism*; D006868:Hydrolysis; D007700:Kinetics; D008868:Microtubule Proteins / Q000378:metabolism*; D008869:Microtubule-Associated Proteins / Q000378:metabolism*; D008870:Microtubules / Q000378:metabolism* / Q000648:ultrastructure
chemical_list: D008868:Microtubule Proteins; D008869:Microtubule-Associated Proteins; D006160:Guanosine Triphosphate