Resolving the molecular structure of microtubules under physiological conditions with scanning force microscopy

Iwan A. T. Schaap1, Pedro J. de Pablo2,1, Christoph F. Schmidt1
1Section Physics of Complex Systems, Department of Physics and Astronomy, Faculty of Sciences, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
2Departamento de Física de la Materia Condensada C-III, Universidad Autónoma de Madrid, Madrid, Spain

Tóm tắt

We have imaged microtubules, essential structural elements of the cytoskeleton in eukaryotic cells, in physiological conditions by scanning force microscopy. We have achieved molecular resolution without the use of cross-linking and chemical fixation methods. With tip forces below 0.3 nN, protofilaments with ~6 nm separation could be clearly distinguished. Lattice defects in the microtubule wall were directly visible, including point defects and protofilament separations. Higher tip forces destroyed the top half of the microtubules, revealing the inner surface of the substrate-attached protofilaments. Monomers could be resolved on these inner surfaces.

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Tài liệu tham khảo

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