Senior Team Leader
Microtubule, Kinesin motility, Tubulin mutants
In neuronal axons, transport of vesicles is mediated by motor proteins such as kinesin and dynein. Our recent results have revealed that microtubules, which have been previously considered as merely a passive track for kinesin, are not actually passive: during the movement of kinesin, microtubules dynamically change their structure over a long range of microns in length. The result implicates a possibility that the state transition of microtubules may play an important role in the mechanism of motility. Our research goal is to understand the molecular mechanism underlying the state transition of microtubules, and elucidate how it is involved in the motility of motor proteins.
Cooperative binding of kinesin molecules to a microtubule in the presence of ATP
The electric properties of a single microtubule filament were studied by observing the orientation process of microtubules in an alternating electric field under dark-field microscopy. The movie shows the movement of a single microtubule filament during application (indicated by <-- -->) of an alternating electric field of 105V/m at a frequency of 1 MHz.
Minoura I, Takazaki H, Ayukawa R, Saruta C, Hachikubo Y, Uchimura S, Hida T, Kamiguchi H, Shimogori T, and Muto E: "Reversal of axonal growth defects in an extraocular fibrosis model by engineering the kinesin-microtubule interface.", Nat Commun, 7, 10058 (2016)
Uchimura S, Fujii T, Takazaki H, Ayukawa R, Nishikawa Y, Minoura I, Hachikubo Y, Kurisu G, Sutoh K, Kon T, Namba K, and Muto E: "A flipped ion pair at the dynein-microtubule interface is critical for dynein motility and ATPase activation.", J Cell Biol, 208(2), 211-222 (2015)
Minoura I, Hachikubo Y, Yamakita Y, Takazaki H, Ayukawa R, Uchimura S, and Muto E: "Overexpression, purification, and functional analysis of recombinant human tubulin dimer.", FEBS Lett, 587(21), 3450-55 (2013)
Uchimura S, Oguchi Y, Hachikubo Y, Ishiwata S, and Muto E: "Key residues on microtubule responsible for activation of kinesin ATPase.", EMBO J, 29(7), 1167-75 (2010)
Minoura I, Katayama E, Sekimoto K, and Muto E: "One-dimensional Brownian motion of charged nanoparticles along microtubules: a model system for weak binding interactions.", Biophys J, 98(8), 1589-97 (2010)
Uchimura S, Oguchi Y, Katsuki M, Usui T, Osada H, Nikawa J, Ishiwata S, and Muto E: "Identification of a strong binding site for kinesin on the microtubule using mutant analysis of tubulin.", EMBO J, 25(24), 5932-41 (2006)
Minoura I, and Muto E: "Dielectric measurement of individual microtubules using the electroorientation method.", Biophys J, 90(10), 3739-48 (2006)
Muto E, Sakai H, and Kaseda K: "Long-range cooperative binding of kinesin to a microtubule in the presence of ATP.", J Cell Biol, 168(5), 691-6 (2005)