title: Dynamic localization of CLIP-170 to microtubule plus ends is coupled to microtubule assembly.
abstract: CLIP-170 is a cytoplasmic linker protein that localizes to plus ends of microtubules in vivo. In this study, we have characterized the microtubule-binding properties of CLIP-170, to understand the mechanism of its plus end targeting. We show that the NH2-terminal microtubule-interacting domain of CLIP-170 alone localizes to microtubule plus ends when transfected into cells. Association of CLIP-170 with newly-formed microtubules was observed in cells microinjected with biotinylated tubulin, used as a tracer for growing microtubules. Using in vitro assays, association of CLIP-170 with recently polymerized tubulin is also seen. Cross-linking and sedimentation velocity experiments suggest association of CLIP-170 with nonpolymerized tubulin. We conclude from these experiments that the microtubule end targeting of CLIP-170 is closely linked to tubulin polymerization.
authors.affiliation: Department of Cell Biology, Sciences III, University of Geneva, CH-1211 Geneva 4, Switzerland. diamantopoulos@cellbio.unige.ch
authors.forename: G S
authors.initials: GS
authors.lastname: Diamantopoulos
authors.forename: F
authors.initials: F
authors.lastname: Perez
authors.forename: H V
authors.initials: HV
authors.lastname: Goodson
authors.forename: G
authors.initials: G
authors.lastname: Batelier
authors.forename: R
authors.initials: R
authors.lastname: Melki
authors.forename: T E
authors.initials: TE
authors.lastname: Kreis
authors.forename: J E
authors.initials: JE
authors.lastname: Rickard
mesh_terms: D018385:Centrosome / Q000378:metabolism; D016244:Guanosine 5'-O-(3-Thiotriphosphate) / Q000378:metabolism; D006160:Guanosine Triphosphate / Q000031:analogs & derivatives / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D008869:Microtubule-Associated Proteins / Q000378:metabolism*; D008870:Microtubules / Q000378:metabolism* / Q000502:physiology; D009363:Neoplasm Proteins; D014404:Tubulin / Q000378:metabolism; D014407:Tumor Cells, Cultured
chemical_list: D008869:Microtubule-Associated Proteins; D009363:Neoplasm Proteins; D014404:Tubulin; C076744:cytoplasmic linker protein 170; D016244:Guanosine 5'-O-(3-Thiotriphosphate); C004805:5'-guanylylmethylenebisphosphonate; D006160:Guanosine Triphosphate