scholarly journals Kinetochore-bound Mps1 regulates kinetochore–microtubule attachments via Ndc80 phosphorylation

2021 ◽  
Vol 220 (12) ◽  
Author(s):  
Krishna K. Sarangapani ◽  
Lori B. Koch ◽  
Christian R. Nelson ◽  
Charles L. Asbury ◽  
Sue Biggins
Keyword(s):  
Error Correction ◽  
Binding Protein ◽  
Genetic Interactions ◽  
Aurora B ◽  
Aurora B Kinase ◽  
Additional Mechanism ◽  
Microtubule Binding ◽  
Chromosome Missegregation ◽  
Dividing Cells

Dividing cells detect and correct erroneous kinetochore–microtubule attachments during mitosis, thereby avoiding chromosome missegregation. The Aurora B kinase phosphorylates microtubule-binding elements specifically at incorrectly attached kinetochores, promoting their release and providing another chance for proper attachments to form. However, growing evidence suggests that the Mps1 kinase is also required for error correction. Here we directly examine how Mps1 activity affects kinetochore–microtubule attachments using a reconstitution-based approach that allows us to separate its effects from Aurora B activity. When endogenous Mps1 that copurifies with kinetochores is activated in vitro, it weakens their attachments to microtubules via phosphorylation of Ndc80, a major microtubule-binding protein. This phosphorylation contributes to error correction because phospho-deficient Ndc80 mutants exhibit genetic interactions and segregation defects when combined with mutants in other error correction pathways. In addition, Mps1 phosphorylation of Ndc80 is stimulated on kinetochores lacking tension. These data suggest that Mps1 provides an additional mechanism for correcting erroneous kinetochore–microtubule attachments, complementing the well-known activity of Aurora B.

scholarly journals Kinetochore-associated Mps1 regulates the strength of kinetochore-microtubule attachments via Ndc80 phosphorylation

2021 ◽  
Author(s):  
Krishna K. Sarangapani ◽  
Lori B. Koch ◽  
Christian R. Nelson ◽  
Charles L. Asbury ◽  
Sue Biggins
Keyword(s):  
Error Correction ◽  
Genetic Interactions ◽  
Aurora B ◽  
Aurora B Kinase ◽  
Additional Mechanism ◽  
Microtubule Binding ◽  
Dividing Cells ◽  
Intrinsic Error

AbstractDividing cells detect and correct erroneous kinetochore-microtubule attachments during mitosis, thereby avoiding chromosome mis-segregation. Most studies of this process have focused on the Aurora B kinase, which phosphorylates microtubule-binding elements specifically at incorrectly attached kinetochores, promoting their release and providing another chance for proper attachments to form. However, growing evidence suggests additional mechanisms, potentially involving Mps1 kinase, that also underlie error correction. Because these mechanisms overlap in vivo, and because both Mps1 and Aurora B function in numerous other vital processes, their contributions to the correction of erroneous kinetochore attachments have been difficult to disentangle. Here we directly examine how Mps1 activity affects kinetochore-microtubule attachments using a reconstitution-based approach that allowed us to separate its effects from Aurora B activity. When endogenous Mps1 that co-purifies with isolated kinetochores is activated in vitro, it weakens their attachments to microtubules via phosphorylation of Ndc80, a major microtubule-binding element of the outer kinetochore. Mps1 phosphorylation of Ndc80 appears to contribute to error correction because phospho-deficient Ndc80 mutants exhibit genetic interactions and segregation defects when combined with mutants in an intrinsic error correction pathway. In addition, Mps1 phosphorylation of Ndc80 is stimulated on kinetochores lacking tension. These data suggest that Mps1 provides an additional mechanism for correcting erroneous kinetochore-microtubule attachments, complementing the well-known activity of Aurora B.

scholarly journals MDM1 is a microtubule-binding protein that negatively regulates centriole duplication

2015 ◽  
Vol 26 (21) ◽  
pp. 3788-3802 ◽  
Author(s):  
Daniel Van de Mark ◽  
Dong Kong ◽  
Jadranka Loncarek ◽  
Tim Stearns
Keyword(s):  
Binding Protein ◽  
Negative Regulator ◽  
Microtubule Binding ◽  
Centriole Duplication ◽  
Mouse Double Minute ◽  
Multiciliated Cells ◽  
Dividing Cells ◽  
Mouse Cells

Mouse double-minute 1 ( Mdm1) was originally identified as a gene amplified in transformed mouse cells and more recently as being highly up-regulated during differentiation of multiciliated epithelial cells, a specialized cell type having hundreds of centrioles and motile cilia. Here we show that the MDM1 protein localizes to centrioles of dividing cells and differentiating multiciliated cells. 3D-SIM microscopy showed that MDM1 is closely associated with the centriole barrel, likely residing in the centriole lumen. Overexpression of MDM1 suppressed centriole duplication, whereas depletion of MDM1 resulted in an increase in granular material that likely represents early intermediates in centriole formation. We show that MDM1 binds microtubules in vivo and in vitro. We identified a repeat motif in MDM1 that is required for efficient microtubule binding and found that these repeats are also present in CCSAP, another microtubule-binding protein. We propose that MDM1 is a negative regulator of centriole duplication and that its function is mediated through microtubule binding.

AZD1152, a novel and selective aurora B kinase inhibitor, induces growth arrest, apoptosis, and sensitization for tubulin depolymerizing agent or topoisomerase II inhibitor in human acute leukemia cells in vitro and in vivo

Blood ◽  
2007 ◽  
Vol 110 (6) ◽  
pp. 2034-2040 ◽  
Author(s):  
Jing Yang ◽  
Takayuki Ikezoe ◽  
Chie Nishioka ◽  
Taizo Tasaka ◽  
Ayuko Taniguchi ◽  
...  
Keyword(s):  
Myeloid Leukemia ◽  
Topoisomerase Ii ◽  
Growth Arrest ◽  
Leukemia Cells ◽  
Aurora B ◽  
Thymidine Uptake ◽  
Aurora B Kinase ◽  
Aurora Kinases ◽  
Topoisomerase Ii Inhibitor

Abstract Aurora kinases play an important role in chromosome alignment, segregation, and cytokinesis during mitosis. We have recently shown that hematopoietic malignant cells including those from acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) aberrantly expressed Aurora A and B kinases, and ZM447439, a potent inhibitor of Aurora kinases, effectively induced growth arrest and apoptosis of a variety of leukemia cells. The present study explored the effect of AZD1152, a highly selective inhibitor of Aurora B kinase, on various types of human leukemia cells. AZD1152 inhibited the proliferation of AML lines (HL-60, NB4, MOLM13), ALL line (PALL-2), biphenotypic leukemia (MV4-11), acute eosinophilic leukemia (EOL-1), and the blast crisis of chronic myeloid leukemia K562 cells with an IC50 ranging from 3 nM to 40 nM, as measured by thymidine uptake on day 2 of culture. These cells had 4N/8N DNA content followed by apoptosis, as measured by cell-cycle analysis and annexin V staining, respectively. Of note, AZD1152 synergistically enhanced the antiproliferative activity of vincristine, a tubulin depolymerizing agent, and daunorubicin, a topoisomerase II inhibitor, against the MOLM13 and PALL-2 cells in vitro. Furthermore, AZD1152 potentiated the action of vincristine and daunorubicin in a MOLM13 murine xenograft model. Taken together, AZD1152 is a promising new agent for treatment of individuals with leukemia. The combined administration of AZD1152 and conventional chemotherapeutic agent to patients with leukemia warrants further investigation.

scholarly journals Centromere-localized Aurora B kinase is required for the fidelity of chromosome segregation

2019 ◽  
Vol 219 (2) ◽  
Author(s):  
Cai Liang ◽  
Zhenlei Zhang ◽  
Qinfu Chen ◽  
Haiyan Yan ◽  
Miao Zhang ◽  
...  
Keyword(s):  
Chromosome Segregation ◽  
Essential Role ◽  
Spindle Assembly Checkpoint ◽  
Histone H3 ◽  
Spindle Assembly ◽  
Aurora B ◽  
Aurora B Kinase ◽  
Chromosome Missegregation ◽  
Proper Timing ◽  
Segregation Of Chromosomes

Aurora B kinase plays an essential role in chromosome bi-orientation, which is a prerequisite for equal segregation of chromosomes during mitosis. However, it remains largely unclear whether centromere-localized Aurora B is required for faithful chromosome segregation. Here we show that histone H3 Thr-3 phosphorylation (H3pT3) and H2A Thr-120 phosphorylation (H2ApT120) can independently recruit Aurora B. Disrupting H3pT3-mediated localization of Aurora B at the inner centromere impedes the decline in H2ApT120 during metaphase and causes H2ApT120-dependent accumulation of Aurora B at the kinetochore-proximal centromere. Consequently, silencing of the spindle assembly checkpoint (SAC) is delayed, whereas the fidelity of chromosome segregation is negligibly affected. Further eliminating an H2ApT120-dependent pool of Aurora B restores proper timing for SAC silencing but increases chromosome missegregation. Our data indicate that H2ApT120-mediated localization of Aurora B compensates for the loss of an H3pT3-dependent pool of Aurora B to correct improper kinetochore–microtubule attachments. This study provides important insights into how centromeric Aurora B regulates SAC and kinetochore attachment to microtubules to ensure error-free chromosome segregation.

scholarly journals The Ndc80 complex bridges two Dam1 complex rings

eLife ◽  
2017 ◽  
Vol 6 ◽  
Author(s):  
Jae ook Kim ◽  
Alex Zelter ◽  
Neil T Umbreit ◽  
Athena Bollozos ◽  
Michael Riffle ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Aurora B ◽  
Aurora B Kinase ◽  
Microtubule Attachment ◽  
Sister Chromatids ◽  
Ndc80 Complex ◽  
Interaction Regions ◽  
Dam1 Complex

Strong kinetochore-microtubule attachments are essential for faithful segregation of sister chromatids during mitosis. The Dam1 and Ndc80 complexes are the main microtubule binding components of the Saccharomyces cerevisiae kinetochore. Cooperation between these two complexes enhances kinetochore-microtubule coupling and is regulated by Aurora B kinase. We show that the Ndc80 complex can simultaneously bind and bridge across two Dam1 complex rings through a tripartite interaction, each component of which is regulated by Aurora B kinase. Mutations in any one of the Ndc80p interaction regions abrogates the Ndc80 complex’s ability to bind two Dam1 rings in vitro, and results in kinetochore biorientation and microtubule attachment defects in vivo. We also show that an extra-long Ndc80 complex, engineered to space the two Dam1 rings further apart, does not support growth. Taken together, our work suggests that each kinetochore in vivo contains two Dam1 rings and that proper spacing between the rings is vital.

scholarly journals CSC-1

2003 ◽  
Vol 161 (2) ◽  
pp. 229-236 ◽  
Author(s):  
Alper Romano ◽  
Annika Guse ◽  
Ivica Krascenicova ◽  
Heinke Schnabel ◽  
Ralf Schnabel ◽  
...  
Keyword(s):  
Caenorhabditis Elegans ◽  
Genetic Analysis ◽  
Chromosome Segregation ◽  
Kinase Activity ◽  
Aurora B ◽  
Aurora B Kinase ◽  
C Elegans ◽  
The Individual

The Aurora B kinase complex is a critical regulator of chromosome segregation and cytokinesis. In Caenorhabditis elegans, AIR-2 (Aurora B) function requires ICP-1 (Incenp) and BIR-1 (Survivin). In various systems, Aurora B binds to orthologues of these proteins. Through genetic analysis, we have identified a new subunit of the Aurora B kinase complex, CSC-1. C. elegans embryos depleted of CSC-1, AIR-2, ICP-1, or BIR-1 have identical phenotypes. CSC-1, BIR-1, and ICP-1 are interdependent for their localization, and all are required for AIR-2 localization. In vitro, CSC-1 binds directly to BIR-1. The CSC-1/BIR-1 complex, but not the individual subunits, associates with ICP-1. CSC-1 associates with ICP-1, BIR-1, and AIR-2 in vivo. ICP-1 dramatically stimulates AIR-2 kinase activity. This activity is not stimulated by CSC-1/BIR-1, suggesting that these two subunits function as targeting subunits for AIR-2 kinase.

scholarly journals Phosphorylation at serine 331 is required for Aurora B activation

2011 ◽  
Vol 195 (3) ◽  
pp. 449-466 ◽  
Author(s):  
Eleni Petsalaki ◽  
Tonia Akoumianaki ◽  
Elizabeth J. Black ◽  
David A.F. Gillespie ◽  
George Zachos
Keyword(s):  
Cell Division ◽  
Kinase Activity ◽  
Aurora B ◽  
Aurora B Kinase ◽  
Chromosomal Passenger Complex ◽  
Chromosome Missegregation ◽  
Mitotic Delay ◽  
Chromosomal Passenger ◽  
Spontaneous Chromosome ◽  
Chk1 Kinase

Aurora B kinase activity is required for successful cell division. In this paper, we show that Aurora B is phosphorylated at serine 331 (Ser331) during mitosis and that phosphorylated Aurora B localizes to kinetochores in prometaphase cells. Chk1 kinase is essential for Ser331 phosphorylation during unperturbed prometaphase or during spindle disruption by taxol but not nocodazole. Phosphorylation at Ser331 is required for optimal phosphorylation of INCENP at TSS residues, for Survivin association with the chromosomal passenger complex, and for complete Aurora B activation, but it is dispensable for Aurora B localization to centromeres, for autophosphorylation at threonine 232, and for association with INCENP. Overexpression of Aurora BS331A, in which Ser331 is mutated to alanine, results in spontaneous chromosome missegregation, cell multinucleation, unstable binding of BubR1 to kinetochores, and impaired mitotic delay in the presence of taxol. We propose that Chk1 phosphorylates Aurora B at Ser331 to fully induce Aurora B kinase activity. These results indicate that phosphorylation at Ser331 is an essential mechanism for Aurora B activation.

scholarly journals Coordinated regulation of the ESCRT-III component CHMP4C by the chromosomal passenger complex and centralspindlin during cytokinesis

Open Biology ◽  
2016 ◽  
Vol 6 (10) ◽  
pp. 160248 ◽  
Author(s):  
Luisa Capalbo ◽  
Ioanna Mela ◽  
Maria Alba Abad ◽  
A. Arockia Jeyaprakash ◽  
J. Michael Edwardson ◽  
...  
Keyword(s):  
Atomic Force Microscopy ◽  
Cell Division ◽  
Aurora B ◽  
Aurora B Kinase ◽  
Chromosomal Passenger Complex ◽  
Force Microscopy ◽  
Daughter Cells ◽  
Atomic Force ◽  
Chromosomal Passenger

The chromosomal passenger complex (CPC)—composed of Aurora B kinase, Borealin, Survivin and INCENP—surveys the fidelity of genome segregation throughout cell division. The CPC has been proposed to prevent polyploidy by controlling the final separation (known as abscission) of the two daughter cells via regulation of the ESCRT-III CHMP4C component. The molecular details are, however, still unclear. Using atomic force microscopy, we show that CHMP4C binds to and remodels membranes in vitro . Borealin prevents the association of CHMP4C with membranes, whereas Aurora B interferes with CHMP4C's membrane remodelling activity. Moreover, we show that CHMP4C phosphorylation is not required for its assembly into spiral filaments at the abscission site and that two distinctly localized pools of phosphorylated CHMP4C exist during cytokinesis. We also characterized the CHMP4C interactome in telophase cells and show that the centralspindlin complex associates preferentially with unphosphorylated CHMP4C in cytokinesis. Our findings indicate that gradual dephosphorylation of CHMP4C triggers a ‘relay’ mechanism between the CPC and centralspindlin that regulates the timely distribution and activation of CHMP4C for the execution of abscission.

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