title: Quantitative analysis of tau-microtubule interaction using FRET.
abstract: The interaction between the microtubule associated protein, tau and the microtubules is investigated. A fluorescence resonance energy transfer (FRET) assay was used to determine the distance separating tau to the microtubule wall, as well as the binding parameters of the interaction. By using microtubules stabilized with Flutax-2 as donor and tau labeled with rhodamine as acceptor, a donor-to-acceptor distance of 54 ± 1 Å was found. A molecular model is proposed in which Flutax-2 is directly accessible to tau-rhodamine molecules for energy transfer. By titration, we calculated the stoichiometric dissociation constant to be equal to 1.0 ± 0.5 µM. The influence of the C-terminal tails of αβ-tubulin on the tau-microtubule interaction is presented once a procedure to form homogeneous solution of cleaved tubulin has been determined. The results indicate that the C-terminal tails of α- and β-tubulin by electrostatic effects and of recruitment seem to be involved in the binding mechanism of tau.
authors.affiliation: Aix-Marseille Université, Inserm, CRO2 UMR_S 911, Faculté de Pharmacie, 27 Bd Jean Moulin, 13385 Marseille, France.
authors.forename: Isabelle L
authors.initials: IL
authors.lastname: Di Maïo
authors.affiliation: Aix-Marseille Université, Inserm, CRO2 UMR_S 911, Faculté de Pharmacie, 27 Bd Jean Moulin, 13385 Marseille, France. pascale.barbier@univ-amu.fr.
authors.forename: Pascale
authors.initials: P
authors.lastname: Barbier
authors.affiliation: Aix-Marseille Université, Inserm, CRO2 UMR_S 911, Faculté de Pharmacie, 27 Bd Jean Moulin, 13385 Marseille, France. diane.allegro@univ-amu.fr.
authors.forename: Diane
authors.initials: D
authors.lastname: Allegro
authors.affiliation: Aix-Marseille Université, Inserm, CRO2 UMR_S 911, Faculté de Pharmacie, 27 Bd Jean Moulin, 13385 Marseille, France. cedric.brault@free.fr.
authors.forename: Cédric
authors.initials: C
authors.lastname: Brault
authors.affiliation: Aix-Marseille Université, Inserm, CRO2 UMR_S 911, Faculté de Pharmacie, 27 Bd Jean Moulin, 13385 Marseille, France. vincent.peyrot@univ-amu.fr.
authors.forename: Vincent
authors.initials: V
authors.lastname: Peyrot
mesh_terms: D031541:Fluorescence Resonance Energy Transfer / Q000379:methods*; D008870:Microtubules / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D043823:Taxoids / Q000737:chemistry / Q000378:metabolism; D014404:Tubulin / Q000737:chemistry / Q000378:metabolism; D016875:tau Proteins / Q000737:chemistry / Q000378:metabolism*
chemical_list: C413450:Flutax 2; D043823:Taxoids; D014404:Tubulin; D016875:tau Proteins