@article {572426,
	title = {Self-organization of stabilized microtubules by both spindle and midzone mechanisms in Xenopus egg cytosol.},
	journal = {Mol Biol Cell},
	volume = {24},
	number = {10},
	year = {2013},
	month = {2013 May},
	pages = {1559-73},
	abstract = {Previous study of self-organization of Taxol-stabilized microtubules into asters in Xenopus meiotic extracts revealed motor-dependent organizational mechanisms in the spindle. We revisit this approach using clarified cytosol with glycogen added back to supply energy and reducing equivalents. We added probes for NUMA and Aurora B to reveal microtubule polarity. Taxol and dimethyl sulfoxide promote rapid polymerization of microtubules that slowly self-organize into assemblies with a characteristic morphology consisting of paired lines or open circles of parallel bundles. Minus ends align in NUMA-containing foci on the outside, and plus ends in Aurora B-containing foci on the inside. Assemblies have a well-defined width that depends on initial assembly conditions, but microtubules within them have a broad length distribution. Electron microscopy shows that plus-end foci are coated with electron-dense material and resemble similar foci in monopolar midzones in cells. Functional tests show that two key spindle assembly factors, dynein and kinesin-5, act during assembly as they do in spindles, whereas two key midzone assembly factors, Aurora B and Kif4, act as they do in midzones. These data reveal the richness of self-organizing mechanisms that operate on microtubules after they polymerize in meiotic cytoplasm and provide a biochemically tractable system for investigating plus-end organization in midzones.},
	keywords = {Animals, Aurora Kinase B, Cell-Free System, Cytokinesis, Cytosol, Dyneins, Kinesin, Meiosis, Microtubules, Oocytes, Protein Stability, Spindle Apparatus, Time-Lapse Imaging, Xenopus laevis, Xenopus Proteins},
	issn = {1939-4586},
	doi = {10.1091/mbc.E12-12-0850},
	author = {Mitchison, Timothy J. and Nguyen, Phuong and Coughlin, Margaret and Groen, Aaron C}
}
