scholarly journals The chromosomal passenger complex and centralspindlin independently contribute to contractile ring assembly

2011 ◽  
Vol 193 (1) ◽  
pp. 155-169 ◽  
Author(s):  
Lindsay Lewellyn ◽  
Ana Carvalho ◽  
Arshad Desai ◽  
Amy S. Maddox ◽  
Karen Oegema
Keyword(s):  
Contractile Ring ◽  
Chromosomal Passenger Complex ◽  
Ring Assembly ◽  
Assembly Pathway ◽  
Chromosomal Passenger ◽  
Spindle Midzone ◽  
Ring Constriction ◽  
Simultaneous Inhibition ◽  
Control Transformation ◽  
Equatorial Band

The chromosomal passenger complex (CPC) and centralspindlin are conserved cytokinesis regulators that localize to the spindle midzone, which forms between the separating chromosomes. Previous work placed the CPC and centralspindlin in a linear pathway that governs midzone formation. Using Caenorhabditis elegans embryos, we test whether there is a similar linear relationship between centralspindlin and the CPC in contractile ring constriction during cytokinesis. We show that simultaneous inhibition of the CPC kinase Aurora BAIR-2 and the centralspindlin component MKLP1ZEN-4 causes an additive constriction defect. Consistent with distinct roles for the proteins, inhibition of filamentous septin guanosine triphosphatases alleviates constriction defects in Aurora BAIR-2–inhibited embryos, whereas inhibition of Rac does so in MKLP1ZEN-4-inhibited embryos. Centralspindlin and the CPC are not required to enrich ring proteins at the cell equator but instead regulate formation of a compact mature ring. Therefore, in contrast to the linear midzone assembly pathway, centralspindlin and the CPC make independent contributions to control transformation of the sheet-like equatorial band into a ribbon-like contractile ring at the furrow tip.

scholarly journals Liquid-liquid phase separation of the chromosomal passenger complex drives parallel bundling of midzone microtubules

2022 ◽  
Author(s):  
Ewa Niedzialkowska ◽  
Tan M Truong ◽  
Luke A Eldredge ◽  
Stefanie Redemann ◽  
Denis Chretien ◽  
...  
Keyword(s):  
Phase Separation ◽  
Liquid Phase ◽  
Chromosome Segregation ◽  
Dynamic Structure ◽  
Liquid Phase Separation ◽  
Chromosomal Passenger Complex ◽  
Chromosomal Passenger ◽  
Spindle Midzone ◽  
Liquid Liquid Phase Separation

The spindle midzone is a dynamic structure that forms during anaphase, mediates chromosome segregation, and provides a signaling platform to position the cleavage furrow. The spindle midzone comprises two antiparallel bundles of microtubules (MTs) but the process of their formation is poorly understood. Here, we show that the Chromosomal Passenger Complex (CPC) undergoes liquid-liquid phase separation (LLPS) to generate parallel MT bundles in vitro when incubated with free tubulin and GTP. MT bundles emerge from CPC droplets with protruding minus-ends that then grow into long, tapered MT structures. During this growth, the CPC in condensates apparently reorganize to coat and bundle the resulting MT structures. CPC mutants attenuated for LLPS or MT binding prevented the generation of parallel MT bundles in vitro and reduced the number of MTs present at spindle midzones in HeLa cells. Our data uncovers a kinase-independent function of the CPC and provides models for how cells generate parallel-bundled MT structures that are important for the assembly of the mitotic spindle.

scholarly journals Kinesins relocalize the chromosomal passenger complex to the midzone for spindle disassembly

2018 ◽  
Vol 217 (5) ◽  
pp. 1687-1700 ◽  
Author(s):  
Itziar Ibarlucea-Benitez ◽  
Luke S. Ferro ◽  
David G. Drubin ◽  
Georjana Barnes
Keyword(s):  
Single Molecule ◽  
Molecular Mechanisms ◽  
Chromosomal Passenger Complex ◽  
Late Anaphase ◽  
Chromosomal Passenger ◽  
Spindle Disassembly ◽  
Spindle Midzone ◽  
Chromosome Separation

Mitotic spindle disassembly after chromosome separation is as important as spindle assembly, yet the molecular mechanisms for spindle disassembly are unclear. In this study, we investigated how the chromosomal passenger complex (CPC), which contains the Aurora B kinase Ipl1, swiftly concentrates at the spindle midzone in late anaphase, and we researched the role of this dramatic relocalization during spindle disassembly. We showed that the kinesins Kip1 and Kip3 are essential for CPC relocalization. In cells lacking Kip1 and Kip3, spindle disassembly is severely delayed until after contraction of the cytokinetic ring. Purified Kip1 and Kip3 interact directly with the CPC and recruit it to microtubules in vitro, and single-molecule experiments showed that the CPC diffuses dynamically on microtubules but that diffusion stops when the CPC encounters a Kip1 molecule. We propose that Kip1 and Kip3 trap the CPC at the spindle midzone in late anaphase to ensure timely spindle disassembly.

scholarly journals Xenopus Shugoshin 2 regulates the spindle assembly pathway mediated by the chromosomal passenger complex

2012 ◽  
Vol 31 (6) ◽  
pp. 1467-1479 ◽  
Author(s):  
Teresa Rivera ◽  
Cristina Ghenoiu ◽  
Miriam Rodríguez-Corsino ◽  
Satoru Mochida ◽  
Hironori Funabiki ◽  
...  
Keyword(s):  
Spindle Assembly ◽  
Chromosomal Passenger Complex ◽  
Assembly Pathway ◽  
Chromosomal Passenger

scholarly journals Contractile Ring-independent Localization of DdINCENP, a Protein Important for Spindle Stability and Cytokinesis

2006 ◽  
Vol 17 (2) ◽  
pp. 779-788 ◽  
Author(s):  
Qian Chen ◽  
Hui Li ◽  
Arturo De Lozanne
Keyword(s):  
Myosin Ii ◽  
Cleavage Furrow ◽  
Contractile Ring ◽  
Subsequent Formation ◽  
Daughter Cells ◽  
Chromosomal Passenger ◽  
Spindle Midzone ◽  
Spindle Stability ◽  
Passenger Protein

Dictyostelium DdINCENP is a chromosomal passenger protein associated with centromeres, the spindle midzone, and poles during mitosis and the cleavage furrow during cytokinesis. Disruption of the single DdINCENP gene revealed important roles for this protein in mitosis and cytokinesis. DdINCENP null cells lack a robust spindle midzone and are hypersensitive to microtubule-depolymerizing drugs, suggesting that their spindles may not be stable. Furthermore DdCP224, a protein homologous to the microtubule-stabilizing protein TOGp/XMAP215, was absent from the spindle midzone of DdINCENP null cells. Overexpression of DdCP224 rescued the weak spindle midzone defect of DdINCENP null cells. Although not required for the localization of the myosin II contractile ring and subsequent formation of a cleavage furrow, DdINCENP is important for the abscission of daughter cells at the end of cytokinesis. Finally, we show that the localization of DdINCENP at the cleavage furrow is modulated by myosin II but it occurs by a mechanism different from that controlling the formation of the contractile ring.

scholarly journals The Localization of the Integral Membrane Protein Cps1p to the Cell Division Site is Dependent on the Actomyosin Ring and the Septation-Inducing Network inSchizosaccharomyces pombe

2002 ◽  
Vol 13 (3) ◽  
pp. 989-1000 ◽  
Author(s):  
Jianhua Liu ◽  
Xie Tang ◽  
Hongyan Wang ◽  
Snezhana Oliferenko ◽  
Mohan K. Balasubramanian
Keyword(s):  
Cell Division ◽  
Membrane Protein ◽  
Integral Membrane Protein ◽  
Wall Material ◽  
Contractile Ring ◽  
Division Site ◽  
Ring Assembly ◽  
Independent Mechanism ◽  
Ring Constriction ◽  
Initial Assembly

Schizosaccharomyces pombe cells divide by medial fission through the use of an actomyosin-based contractile ring. Constriction of the actomyosin ring is accompanied by the centripetal addition of new membranes and cell wall material. In this article, we characterize the mechanism responsible for the localization of Cps1p, a septum-synthesizing 1,3-β-glucan synthase, to the division site during cytokinesis. We show that Cps1p is an integral membrane protein that localizes to the cell division site late in anaphase. Neither F-actin nor microtubules are essential for the initial assembly of Cps1p to the medial division site. F-actin, but not microtubules, is however important for the eventual incorporation of Cps1p into the actomyosin ring. Assembly of Cps1p into the cell division ring is also dependent on the septation-inducing network (SIN) proteins that regulate division septum formation after assembly of the actomyosin ring. Fluorescence-recovery after-photobleaching experiments reveal that Cps1p does not diffuse appreciably within the plasma membrane and is retained at the division site by a mechanism that does not depend on an intact F-actin cytoskeleton. We conclude that the actomyosin ring serves as a spatial cue for Cps1p localization, whereas the maintenance of Cps1p at the division site occurs by a novel F-actin– and microtubule-independent mechanism. Furthermore, we propose that the SIN proteins ensure localization of Cps1p at the appropriate point in the cell cycle.

scholarly journals The Cul3–KLHL21 E3 ubiquitin ligase targets Aurora B to midzone microtubules in anaphase and is required for cytokinesis

2009 ◽  
Vol 187 (6) ◽  
pp. 791-800 ◽  
Author(s):  
Sarah Maerki ◽  
Michael H. Olma ◽  
Titu Staubli ◽  
Patrick Steigemann ◽  
Daniel W. Gerlich ◽  
...  
Keyword(s):  
Ubiquitin Ligase ◽  
E3 Ubiquitin Ligase ◽  
Ubiquitin Ligases ◽  
Aurora B ◽  
Chromosomal Passenger Complex ◽  
Chromosome Alignment ◽  
Chromosomal Passenger ◽  
Spindle Midzone ◽  
Broad Complex

Cul3 (Cullin3)-based E3 ubiquitin ligases recently emerged as critical regulators of mitosis. In this study, we identify two mammalian BTB (Bric-a-brac–Tramtrack–Broad complex)-Kelch proteins, KLHL21 and KLHL22, that interact with Cul3 and are required for efficient chromosome alignment. Interestingly, KLHL21 but not KLHL22 is necessary for cytokinesis and regulates translocation of the chromosomal passenger complex (CPC) from chromosomes to the spindle midzone in anaphase, similar to the previously described BTB-Kelch proteins KLHL9 and KLHL13. KLHL21 directly binds to Aurora B and mediates ubiquitination of Aurora B in vitro. In contrast to KLHL9 and KLHL13, KLHL21 localizes to midzone microtubules in anaphase and recruits Aurora B and Cul3 to this region. Together, our results suggest that different Cul3 adaptors nonredundantly regulate Aurora B during mitosis, possibly by ubiquitinating different pools of Aurora B at distinct subcellular localizations.

scholarly journals Mutual Dependence of Mob1 and the Chromosomal Passenger Complex for Localization during Mitosis

2010 ◽  
Vol 21 (3) ◽  
pp. 380-392 ◽  
Author(s):  
Lori Jo Wilmeth ◽  
Sanjay Shrestha ◽  
Gilbert Montaño ◽  
Jennifer Rashe ◽  
Charles Bradley Shuster
Keyword(s):  
Mitotic Exit ◽  
Signaling Cascades ◽  
Mitotic Progression ◽  
Chromosomal Passenger Complex ◽  
Related Family ◽  
Cytoplasmic Material ◽  
Spindle Poles ◽  
Chromosomal Passenger ◽  
Early Anaphase ◽  
Spindle Midzone

The spatial and temporal coordination of chromosome segregation with cytokinesis is essential to ensure that each daughter cell receives the correct complement of chromosomal and cytoplasmic material. In yeast, mitotic exit and cytokinesis are coordinated by signaling cascades whose terminal components include a nuclear Dbf2-related family kinase and a noncatalytic subunit, Mps one binding (Mob) 1. There are five human Mob1 isoforms, all of which display redundant localization patterns at the spindle poles and kinetochores in early mitosis, and the spindle midzone during cytokinesis. Mob1 shares similar localization patterns to Polo-like kinase (Plk1) and the chromosomal passenger complex (CPC), and although depletion of Plk1 resulted in a loss of Mob1 from the spindle poles, Mob1 recruitment to kinetochores was unaffected. Conversely, disruption of CPC signaling resulted in a loss of Mob1 from kinetochores without disrupting recruitment to the spindle poles. In Mob1-depleted cells, the relocalization of the CPC and mitotic kinesin-like protein (MKLP) 2 to the spindle midzone was delayed during early anaphase, and as a consequence, the midzone recruitment of MKLP1 also was affected. Together, these results suggest that Mob1 and the other mammalian orthologues of the mitotic exit network regulate mitotic progression by facilitating the timely mobilization of the CPC to the spindle midzone.

Functional midbody assembly in the absence of a central spindle

2022 ◽  
Vol 221 (3) ◽  
Author(s):  
Sophia M. Hirsch ◽  
Frances Edwards ◽  
Mimi Shirasu-Hiza ◽  
Julien Dumont ◽  
Julie C. Canman
Keyword(s):  
Microtubule Assembly ◽  
Primary Role ◽  
Intercellular Bridge ◽  
Contractile Ring ◽  
Spindle Microtubule ◽  
Central Spindle ◽  
Family Protein ◽  
Spindle Midzone ◽  
Ring Constriction ◽  
Spindle Microtubules

Contractile ring constriction during cytokinesis is thought to compact central spindle microtubules to form the midbody, an antiparallel microtubule bundle at the intercellular bridge. In Caenorhabditis elegans, central spindle microtubule assembly requires targeting of the CLASP family protein CLS-2 to the kinetochores in metaphase and spindle midzone in anaphase. CLS-2 targeting is mediated by the CENP-F–like HCP-1/2, but their roles in cytokinesis and midbody assembly are not known. We found that although HCP-1 and HCP-2 mostly function cooperatively, HCP-1 plays a more primary role in promoting CLS-2–dependent central spindle microtubule assembly. HCP-1/2 codisrupted embryos did not form central spindles but completed cytokinesis and formed functional midbodies capable of supporting abscission. These central spindle–independent midbodies appeared to form via contractile ring constriction–driven bundling of astral microtubules at the furrow tip. This work suggests that, in the absence of a central spindle, astral microtubules can support midbody assembly and that midbody assembly is more predictive of successful cytokinesis than central spindle assembly.

scholarly journals The multifunctional spindle midzone in vertebrate cells at a glance

2021 ◽  
Vol 134 (10) ◽  
Author(s):  
Patricia Wadsworth
Keyword(s):  
Chromosome Segregation ◽  
Future Research ◽  
Contractile Ring ◽  
Microtubule Associated Proteins ◽  
Ring Assembly ◽  
Open Questions ◽  
Associated Proteins ◽  
Spindle Midzone ◽  
Spindle Elongation ◽  
And Function

ABSTRACT During anaphase, a microtubule-containing structure called the midzone forms between the segregating chromosomes. The midzone is composed of an antiparallel array of microtubules and numerous microtubule-associated proteins that contribute to midzone formation and function. In many cells, the midzone is an important source of signals that specify the location of contractile ring assembly and constriction. The midzone also contributes to the events of anaphase by generating forces that impact chromosome segregation and spindle elongation; some midzone components contribute to both processes. The results of recent experiments have increased our understanding of the importance of the midzone, a microtubule array that has often been overlooked. This Journal of Cell Science at a Glance article will review, and illustrate on the accompanying poster, the organization, formation and dynamics of the midzone, and discuss open questions for future research.

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