Minus-End Growth, Reconstituted Spindle Midzones, and Contorted Microtubules

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Patronin-Mediated Minus End Growth Is Required For Dendritic Microtubule Polarity

Feng et al. | Journal of Cell Biology Microtubule minus-ends are often stably capped in cells, yielding the spotlight to their more dynamic plus-end counterparts. However, dendritic neurons present a compelling case for significant minus-end growth in vivo as >90% of microtubules are arranged with their minus-ends directed outward. In this study, the Rolls Lab monitors microtubule polymerization in Drosophila and zebrafish neurons with EB1 tracking and discovers an unexpected population of slow-moving puncta (~1 μm/min) with speed and direction suggestive of growing minus-ends. Using genetic perturbations, the authors further identify Patronin as a critical proponent of minus-end growth and “minus-end-out” microtubule architecture. Overall, this study provides the first evidence of slow growing minus-ends in neurons and demonstrates a novel role for Patronin in microtubule organization.
 

“The finding that Drosophila Patronin facilitates, rather than reduces, minus end growth in neurons is surprising in light of its previous characterization.”

Spotlight by Heather T. Broihier

Methods

Live Cell Imaging of Meiosis in Arabidopsis thaliana

Researchers develop a novel reporter cell line combined with morphological analysis to study plant cell meiosis in real time.
Prusicki et al.  |  eLife
 

The Kinetics of Nucleotide Binding to Isolated Chlamydomonas Axonemes using UV-TIRF Microscopy

By studying the recovery of mantATP fluorescence, researchers observe the travelling wave of dynein activity in the axoneme.
Feofilova, Mahamdeh, and Howard  |  Biophysical Journal

Reviews and Perspectives

Tools and Resources

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