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