title: Photoclickable dendritic molecular glue: noncovalent-to-covalent photochemical transformation of protein hybrids.
abstract: A water-soluble dendron with a fluorescein isothiocyanate (FITC) fluorescent label and bearing nine pendant guanidinium ion (Gu(+))/benzophenone (BP) pairs at its periphery (Glue(BP)-FITC) serves as a "photoclickable molecular glue". By multivalent salt-bridge formation between Gu(+) ions and oxyanions, Glue(BP)-FITC temporarily adheres to a kinesin/microtubule hybrid. Upon subsequent exposure to UV light, this noncovalent binding is made permanent via a cross-linking reaction mediated by carbon radicals derived from the photoexcited BP units. This temporal-to-permanent transformation by light occurs quickly and efficiently in this preorganized state, allowing the movements of microtubules on a kinesin-coated glass plate to be photochemically controlled. A fundamental difference between such temporal and permanent bindings was visualized by the use of "optical tweezers".
authors.affiliation: Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Tokyo 113-8656, Japan.
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Uchida
authors.forename: Kou
authors.initials: K
authors.lastname: Okuro
authors.forename: Yamato
authors.initials: Y
authors.lastname: Niitani
authors.forename: Xiao
authors.initials: X
authors.lastname: Ling
authors.forename: Takayuki
authors.initials: T
authors.lastname: Ariga
authors.forename: Michio
authors.initials: M
authors.lastname: Tomishige
authors.forename: Takuzo
authors.initials: T
authors.lastname: Aida
mesh_terms: D000818:Animals; D001577:Benzophenones / Q000737:chemistry*; D002414:Cations, Monovalent / Q000737:chemistry; D002417:Cattle; D016650:Fluorescein-5-isothiocyanate / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000737:chemistry*; D019791:Guanidine / Q000737:chemistry*; D016547:Kinesins / Q000737:chemistry* / Q000648:ultrastructure; D008870:Microtubules / Q000737:chemistry* / Q000648:ultrastructure; D008958:Models, Molecular; D055668:Photochemical Processes; D012710:Serum Albumin, Bovine / Q000737:chemistry; D014466:Ultraviolet Rays
chemical_list: D001577:Benzophenones; D002414:Cations, Monovalent; D005456:Fluorescent Dyes; D012710:Serum Albumin, Bovine; C047723:benzophenone; D016547:Kinesins; D016650:Fluorescein-5-isothiocyanate; D019791:Guanidine