title: Inhibition of microtubule nucleation at the neuronal centrosome compromises axon growth.
abstract: We tested the dependence of axon growth on microtubule (MT) nucleation from the neuronal centrosome. Nocodazole diminished MTs in freshly plated neurons by > 99%. Within 5 min of drug removal, MTs reassembled at the centrosome. This response was inhibited in cells microinjected with gamma-tubulin antibody. Within 2 hr of drug removal, uninjected neurons grew > 500 microns of axon. In roughly half of the antibody-injected cells, axon growth was abolished and MT levels were reduced by approximately 87% compared with uninjected cells. In the other antibody-injected cells, axon growth was compromised but not abolished, and MT levels were reduced by approximately 38%. Thus inhibition of MT nucleation at the centrosome hindered MT reassembly, and depending on the severity of this response, axon growth was either compromised or abolished.
authors.affiliation: Department of Anatomy, University of Wisconsin Medical School, Madison 53706.
authors.forename: F J
authors.initials: FJ
authors.lastname: Ahmad
authors.forename: H C
authors.initials: HC
authors.lastname: Joshi
authors.forename: V E
authors.initials: VE
authors.lastname: Centonze
authors.forename: P W
authors.initials: PW
authors.lastname: Baas
mesh_terms: D000818:Animals; D000906:Antibodies / Q000494:pharmacology; D001369:Axons / Q000187:drug effects / Q000502:physiology*; D008845:Microinjections; D008870:Microtubules / Q000187:drug effects / Q000502:physiology*; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D014404:Tubulin / Q000276:immunology
chemical_list: D000906:Antibodies; D014404:Tubulin