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arXiv · 0911.1490

Visualizing individual microtubules using bright-field microscopy

Braulio Gutiérrez-Medina·Steven M. Block
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Abstract

Microtubules are filament-shaped, polymeric proteins (~25 nm in diameter) involved in cellular structure and organization. We demonstrate the imaging of individual microtubules using a conventional bright-field microscope, without any additional phase or polarization optics. Light scattered by microtubules is discriminated through extensive use of digital image-processing, thus removing background, reducing noise and enhancing contrast. The setup builds on a commercial microscope, with the inclusion of a minimal and inexpensive set of components, suitable for implementation in the student laboratory. We show how this technique can be applied to a demonstrative biophysical assay, by tracking the motions of microtubules driven by the motor protein kinesin.

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Braulio Gutiérrez-Medina, Steven M. Block. 2009-11-08. Visualizing individual microtubules using bright-field microscopy. https://doi.org/10.1119/1.3453264

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