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Full-Text Articles in Life Sciences
Poleward Transport Of Tpx2 In The Mammalian Mitotic Spindle Requires Dynein, Eg5, And Microtubule Flux, Patricia Wadsworth, N. Ma, S. Tulu, N. Ferenz, C. Fagerstrom, A. Mogilner
Poleward Transport Of Tpx2 In The Mammalian Mitotic Spindle Requires Dynein, Eg5, And Microtubule Flux, Patricia Wadsworth, N. Ma, S. Tulu, N. Ferenz, C. Fagerstrom, A. Mogilner
Patricia Wadsworth
TPX2 is a Ran-regulated spindle assembly factor that is required for kinetochore fiber formation and activation of the mitotic kinase Aurora A. TPX2 is enriched near spindle poles and is required near kinetochores, suggesting that it undergoes dynamic relocalization throughout mitosis. Using photoactivation, we measured the movement of PA-GFP-TPX2 in the mitotic spindle. TPX2 moves poleward in the half-spindle and is static in the interzone and near spindle poles. Poleward transport of TPX2 is sensitive to inhibition of dynein or Eg5 and to suppression of microtubule flux with nocodazole or antibodies to Kif2a. Poleward transport requires the C terminus of …
Dual Role For Microtubules In Regulating Cortical Contractility During Cytokinesis, Patricia Wadsworth, K. Murphy
Dual Role For Microtubules In Regulating Cortical Contractility During Cytokinesis, Patricia Wadsworth, K. Murphy
Patricia Wadsworth
Microtubules stimulate contractile-ring formation in the equatorial cortex and simultaneously suppress contractility in the polar cortex; how they accomplish these differing activities is incompletely understood. We measured the behavior of GFP-actin in mammalian cells treated with nocodazole under conditions that either completely eliminate microtubules or selectively disassemble astral microtubules. Selective disassembly of astral microtubules resulted in functional contractile rings that were wider than controls and had altered dynamic activity, as measured by FRAP. Complete microtubule disassembly or selective loss of astral microtubules resulted in wave-like contractile behavior of actin in the non-equatorial cortex, and mislocalization of myosin II and Rho. …
Centrosome Reorientation In Wound-Edge Cells Is Cell Type Specific, Patricia Wadsworth, A. C. Yvon, J. W. Walker, B. A. Danowski, C. Fagerstrom, A. Khojakov
Centrosome Reorientation In Wound-Edge Cells Is Cell Type Specific, Patricia Wadsworth, A. C. Yvon, J. W. Walker, B. A. Danowski, C. Fagerstrom, A. Khojakov
Patricia Wadsworth
The reorientation of the microtubule organizing center during cell migration into a wound in the monolayer was directly observed in living wound-edge cells expressing γ-tubulin tagged with green fluorescent protein. Our results demonstrate that in CHO cells, the centrosome reorients to a position in front of the nucleus, toward the wound edge, whereas in PtK cells, the centrosome lags behind the nucleus during migration into the wound. In CHO cells, the average rate of centrosome motion was faster than that of the nucleus; the converse was true in PtK cells. In both cell lines, centrosome motion was stochastic, with periods …