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Measuring microtubule polarity in spindles with second-harmonic generation.

ABSTRACT: The spatial organization of microtubule polarity, and the interplay between microtubule polarity and protein localization, is thought to be crucial for spindle assembly, anaphase, and cytokinesis, but these phenomena remain poorly understood, in part due to the difficulty of measuring microtubule polarity in spindles. We develop and implement a method to nonperturbatively and quantitatively measure microtubule polarity throughout spindles using a combination of second-harmonic generation and two-photon fluorescence. We validate this method using computer simulations and by comparison to structural data on spindles obtained from electron tomography and laser ablation. This method should provide a powerful tool for studying spindle organization and function, and may be applicable for investigating microtubule polarity in other systems.

SUBMITTER: Yu CH

PROVIDER: S-EPMC4008835 | biostudies-other | 2014 Apr

REPOSITORIES: biostudies-other

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Measuring microtubule polarity in spindles with second-harmonic generation.

Yu Che-Hang CH Langowitz Noah N Wu Hai-Yin HY Farhadifar Reza R Brugues Jan J Yoo Tae Yeon TY Needleman Daniel D

Biophysical journal 20140401 8

The spatial organization of microtubule polarity, and the interplay between microtubule polarity and protein localization, is thought to be crucial for spindle assembly, anaphase, and cytokinesis, but these phenomena remain poorly understood, in part due to the difficulty of measuring microtubule polarity in spindles. We develop and implement a method to nonperturbatively and quantitatively measure microtubule polarity throughout spindles using a combination of second-harmonic generation and two ...[more]

PMID: 24739157

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