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Electron tomography reveals a flared morphology on growing microtubule ends.

ABSTRACT: Microtubules (MTs) exhibit dynamic instability, alternating between phases of growth and shortening, mostly at their uncapped plus ends. Based on results from cryo-electron microscopy it was proposed that growing MTs display mainly curved sheets and blunt ends; during depolymerisation curled 'ramshorns' predominate. Observations of MTs in mitotic cells have suggested that the situation in vivo differs from that in vitro, but so far, a clear comparison between in vivo and in vitro results has not been possible because MT end structures could not be correlated directly with the dynamic state of that particular MT. Here we combine light microscopy and electron tomography (ET) to show that growing MT plus ends in the fission yeast Schizosaccharomyces pombe display predominantly a flared morphology. This indicates that MT polymerisation in vivo and in vitro can follow different paths.

SUBMITTER: Hoog JL

PROVIDER: S-EPMC3039015 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature

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Electron tomography reveals a flared morphology on growing microtubule ends.

Höög Johanna L JL Huisman Stephen M SM Sebö-Lemke Zsofia Z Sandblad Linda L McIntosh J Richard JR Antony Claude C Brunner Damian D

Journal of cell science 20110208 Pt 5

Microtubules (MTs) exhibit dynamic instability, alternating between phases of growth and shortening, mostly at their uncapped plus ends. Based on results from cryo-electron microscopy it was proposed that growing MTs display mainly curved sheets and blunt ends; during depolymerisation curled 'ramshorns' predominate. Observations of MTs in mitotic cells have suggested that the situation in vivo differs from that in vitro, but so far, a clear comparison between in vivo and in vitro results has not ...[more]

PMID: 21303925

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