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Drosophila katanin-60 depolymerizes and severs at microtubule defects.

ABSTRACT: Microtubule (MT) length and location is tightly controlled in cells. One novel family of MT-associated proteins that regulates MT dynamics is the MT-severing enzymes. In this work, we investigate how katanin (p60), believed to be the first discovered severing enzyme, binds and severs MTs via single molecule total internal reflection fluorescence microscopy. We find that severing activity depends on katanin concentration. We also find that katanin can remove tubulin dimers from the ends of MTs, appearing to depolymerize MTs. Strikingly, katanin localizes and severs at the interface of GMPCPP-tubulin and GDP-tubulin suggesting that it targets to protofilament-shift defects. Finally, we observe that binding duration, mobility, and oligomerization are ATP dependent.

SUBMITTER: Diaz-Valencia JD

PROVIDER: S-EPMC3093562 | biostudies-literature | 2011 May

REPOSITORIES: biostudies-literature

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Drosophila katanin-60 depolymerizes and severs at microtubule defects.

Díaz-Valencia Juan Daniel JD Morelli Margaret M MM Bailey Megan M Zhang Dong D Sharp David J DJ Ross Jennifer L JL

Biophysical journal 20110501 10

Microtubule (MT) length and location is tightly controlled in cells. One novel family of MT-associated proteins that regulates MT dynamics is the MT-severing enzymes. In this work, we investigate how katanin (p60), believed to be the first discovered severing enzyme, binds and severs MTs via single molecule total internal reflection fluorescence microscopy. We find that severing activity depends on katanin concentration. We also find that katanin can remove tubulin dimers from the ends of MTs, a ...[more]

PMID: 21575578

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