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Separase Regulates INCENP-Aurora B Anaphase Spindle Function Through Cdc14

About: The article was published on 2003-01-01 and is currently open access. It has received 63 citations till now. The article focuses on the topics: Separase & Securin.
Citations
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Journal ArticleDOI
TL;DR: This work has shown that Aurora B is one of the most intensively studied kinases and in conjunction with inner centromere protein, borealin and survivin it forms the chromosomal passenger complex (CPC), which regulates key mitotic events.
Abstract: Successful cell division requires the precise and timely coordination of chromosomal, cytoskeletal and membrane trafficking events. These processes are regulated by the competing actions of protein kinases and phosphatases. Aurora B is one of the most intensively studied kinases. In conjunction with inner centromere protein (INCENP), borealin (also known as Dasra) and survivin it forms the chromosomal passenger complex (CPC). This complex targets to different locations at differing times during mitosis, where it regulates key mitotic events: correction of chromosome-microtubule attachment errors; activation of the spindle assembly checkpoint; and construction and regulation of the contractile apparatus that drives cytokinesis. Our growing understanding of the CPC has seen it develop from a mere passenger riding on the chromosomes to one of the main controllers of mitosis.

763 citations

Journal ArticleDOI
TL;DR: This mutant collection should facilitate a wide range of systematic studies aimed at understanding the functions of essential genes, including roles for cohesin and condensin genes in spindle disassembly.
Abstract: Conditional temperature-sensitive (ts) mutations are valuable reagents for studying essential genes in the yeast Saccharomyces cerevisiae. We constructed 787 ts strains, covering 497 (∼45%) of the 1,101 essential yeast genes, with ∼30% of the genes represented by multiple alleles. All of the alleles are integrated into their native genomic locus in the S288C common reference strain and are linked to a kanMX selectable marker, allowing further genetic manipulation by synthetic genetic array (SGA)-based, high-throughput methods. We show two such manipulations: barcoding of 440 strains, which enables chemical-genetic suppression analysis, and the construction of arrays of strains carrying different fluorescent markers of subcellular structure, which enables quantitative analysis of phenotypes using high-content screening. Quantitative analysis of a GFP-tubulin marker identified roles for cohesin and condensin genes in spindle disassembly. This mutant collection should facilitate a wide range of systematic studies aimed at understanding the functions of essential genes.

404 citations

Journal ArticleDOI
TL;DR: The chromosomal passenger complex provides an essential mechanism for mitotic regulation and involves proteins involved in coordinating the chromosomal and cytoskeletal events of mitosis.
Abstract: Chromosomal passengers are proteins that are involved in coordinating the chromosomal and cytoskeletal events of mitosis. The passengers are present in cells as a complex with at least four members: Aurora B, a protein kinase; inner centromeric protein, an activation and targeting subunit; Survivin (function unknown) and Borealin (function also unknown). The kinase is activated at the onset of mitosis, at least partly accomplished by regulation of the levels of its constituents. As mitosis progresses, the kinase complex moves to a highly choreographed series of locations in the mitotic cell, activating key substrates at precise locations and specific times. Functions that require chromosomal passenger activity include chromatin modification (phosphorylation of histone H3), correction of kinetochore attachment errors, aspects of the spindle assembly checkpoint, assembly of a stable bipolar spindle and the completion of cytokinesis. The chromosomal passenger complex provides an essential mechanism for mitotic regulation.

351 citations


Cites background from "Separase Regulates INCENP-Aurora B ..."

  • ...A nonphosphorylable mutant of INCENP transfers to the midzone prior to anaphase onset; however, it is not sufficient to compensate for the fragility of the anaphase spindle in a Cdc14 mutant background....

    [...]

  • ...The dephosphorylation is mediated by Cdc14 phosphatase, which, in turn, is activated by separase (Pereira and Schiebel 2003) The INCENP gene is essential in mouse (Cutts et al. 1999), yeasts (Kim et al. 1999), Caenorhabditis elegans Communicated by E.A. Nigg P. Vagnarelli (*) ....

    [...]

  • ...This localization—at least in budding yeast—depends upon the dephosphorylation of INCENP by Cdc14 (Pereira and Schiebel 2003)....

    [...]

  • ...The dephosphorylation is mediated by Cdc14 phosphatase, which, in turn, is activated by separase (Pereira and Schiebel 2003) The INCENP gene is essential in mouse (Cutts et al....

    [...]

Journal ArticleDOI
TL;DR: This work has shown that the key mitotic exit phosphatase in budding yeast, Cdc14, is now well understood, and in animal cells, it is now emerging that mitoticexit relies on distinct regulatory networks, including the protein phosphatases PP1 and PP2A.
Abstract: The mitosis-to-interphase transition involves dramatic cellular reorganization from a state that supports chromosome segregation to a state that complies with all functions of an interphase cell. This process, termed mitotic exit, depends on the removal of mitotic phosphorylations from a broad range of substrates. Mitotic exit regulation involves inactivation of mitotic kinases and activation of counteracting protein phosphatases. The key mitotic exit phosphatase in budding yeast, Cdc14, is now well understood. By contrast, in animal cells, it is now emerging that mitotic exit relies on distinct regulatory networks, including the protein phosphatases PP1 and PP2A.

294 citations

Journal ArticleDOI
17 Jul 2008-Nature
TL;DR: It is demonstrated that the cyclin-dependent kinase 1 (Cdk1)-dependent phosphorylation of securin near its destruction-box motif inhibits Securin ubiquitination by the APC, and that mutations that disruptSecurin phosphoregulation decrease the synchrony of chromosome segregation.
Abstract: The cell cycle couples growth and cell division to ensure the consistent size and shape of individual cells. This involves a vast array of genes and proteins, and requires sophisticated mechanisms to keep them acting in step. Two reports in this issue focus on different points in the cell cycle of the budding yeast Saccharomyces cerevisiae, and find that in each case, positive feedback keeps the process on the rails. Skotheim et al. studied the Start checkpoint in the G1 cell cycle phase, where cells irreversibly commit to cell division. Single-cell analysis reveals that Start is a positive feedback-dependent switch that coordinates the simultaneous transcription of a large group of cell cycle genes and the budding of a daughter cell. Holt et al. studied the onset of anaphase in mitosis, at which chromosome pairs separate abruptly and simultaneously. Cohesion between sister chromatids is dissolved by the enzyme separase, which is held in check by securin. A positive feedback loop regulating the ubiquitination and destruction of securin appears to make anaphase a switch-like event. Chromosomes separate abruptly during anaphase of mitosis, but how this switch-like behaviour is achieved is unclear. Cohesion between sister chromatids is dissolved by the protease separase, which is held in check by securin. In this paper, a positive feedback loop regulating the ubiquitination and destruction of securin is proposed to make anaphase more switch-like. At the onset of anaphase, sister-chromatid cohesion is dissolved abruptly and irreversibly, ensuring that all chromosome pairs disjoin almost simultaneously. The regulatory mechanisms that generate this switch-like behaviour are unclear. Anaphase is initiated when a ubiquitin ligase, the anaphase-promoting complex (APC), triggers the destruction of securin, thereby allowing separase, a protease, to disrupt sister-chromatid cohesion1,2,3,4. Here we demonstrate that the cyclin-dependent kinase 1 (Cdk1)-dependent phosphorylation of securin near its destruction-box motif inhibits securin ubiquitination by the APC. The phosphatase Cdc14 reverses securin phosphorylation, thereby increasing the rate of securin ubiquitination. Because separase is known to activate Cdc14 (refs 5 and 6), our results support the existence of a positive feedback loop that increases the abruptness of anaphase. Consistent with this model, we show that mutations that disrupt securin phosphoregulation decrease the synchrony of chromosome segregation. Our results also suggest that coupling securin degradation with changes in Cdk1 and Cdc14 activities helps coordinate the initiation of sister-chromatid separation with changes in spindle dynamics.

200 citations

References
More filters
Journal ArticleDOI
TL;DR: This work has shown that Aurora B is one of the most intensively studied kinases and in conjunction with inner centromere protein, borealin and survivin it forms the chromosomal passenger complex (CPC), which regulates key mitotic events.
Abstract: Successful cell division requires the precise and timely coordination of chromosomal, cytoskeletal and membrane trafficking events. These processes are regulated by the competing actions of protein kinases and phosphatases. Aurora B is one of the most intensively studied kinases. In conjunction with inner centromere protein (INCENP), borealin (also known as Dasra) and survivin it forms the chromosomal passenger complex (CPC). This complex targets to different locations at differing times during mitosis, where it regulates key mitotic events: correction of chromosome-microtubule attachment errors; activation of the spindle assembly checkpoint; and construction and regulation of the contractile apparatus that drives cytokinesis. Our growing understanding of the CPC has seen it develop from a mere passenger riding on the chromosomes to one of the main controllers of mitosis.

763 citations

Journal ArticleDOI
TL;DR: This mutant collection should facilitate a wide range of systematic studies aimed at understanding the functions of essential genes, including roles for cohesin and condensin genes in spindle disassembly.
Abstract: Conditional temperature-sensitive (ts) mutations are valuable reagents for studying essential genes in the yeast Saccharomyces cerevisiae. We constructed 787 ts strains, covering 497 (∼45%) of the 1,101 essential yeast genes, with ∼30% of the genes represented by multiple alleles. All of the alleles are integrated into their native genomic locus in the S288C common reference strain and are linked to a kanMX selectable marker, allowing further genetic manipulation by synthetic genetic array (SGA)-based, high-throughput methods. We show two such manipulations: barcoding of 440 strains, which enables chemical-genetic suppression analysis, and the construction of arrays of strains carrying different fluorescent markers of subcellular structure, which enables quantitative analysis of phenotypes using high-content screening. Quantitative analysis of a GFP-tubulin marker identified roles for cohesin and condensin genes in spindle disassembly. This mutant collection should facilitate a wide range of systematic studies aimed at understanding the functions of essential genes.

404 citations

Journal ArticleDOI
TL;DR: The chromosomal passenger complex provides an essential mechanism for mitotic regulation and involves proteins involved in coordinating the chromosomal and cytoskeletal events of mitosis.
Abstract: Chromosomal passengers are proteins that are involved in coordinating the chromosomal and cytoskeletal events of mitosis. The passengers are present in cells as a complex with at least four members: Aurora B, a protein kinase; inner centromeric protein, an activation and targeting subunit; Survivin (function unknown) and Borealin (function also unknown). The kinase is activated at the onset of mitosis, at least partly accomplished by regulation of the levels of its constituents. As mitosis progresses, the kinase complex moves to a highly choreographed series of locations in the mitotic cell, activating key substrates at precise locations and specific times. Functions that require chromosomal passenger activity include chromatin modification (phosphorylation of histone H3), correction of kinetochore attachment errors, aspects of the spindle assembly checkpoint, assembly of a stable bipolar spindle and the completion of cytokinesis. The chromosomal passenger complex provides an essential mechanism for mitotic regulation.

351 citations

Journal ArticleDOI
TL;DR: This work has shown that the key mitotic exit phosphatase in budding yeast, Cdc14, is now well understood, and in animal cells, it is now emerging that mitoticexit relies on distinct regulatory networks, including the protein phosphatases PP1 and PP2A.
Abstract: The mitosis-to-interphase transition involves dramatic cellular reorganization from a state that supports chromosome segregation to a state that complies with all functions of an interphase cell. This process, termed mitotic exit, depends on the removal of mitotic phosphorylations from a broad range of substrates. Mitotic exit regulation involves inactivation of mitotic kinases and activation of counteracting protein phosphatases. The key mitotic exit phosphatase in budding yeast, Cdc14, is now well understood. By contrast, in animal cells, it is now emerging that mitotic exit relies on distinct regulatory networks, including the protein phosphatases PP1 and PP2A.

294 citations

Journal ArticleDOI
19 Aug 2004-Nature
TL;DR: Phosphoregulation of the motor domain of MKLP1 kinesin ensures that central spindle assembly occurs at the appropriate time in the cell cycle and maintains genomic stability.
Abstract: The bipolar mitotic spindle is responsible for segregating sister chromatids at anaphase. Microtubule motor proteins generate spindle bipolarity and enable the spindle to perform mechanical work. A major change in spindle architecture occurs at anaphase onset when central spindle assembly begins. This structure regulates the initiation of cytokinesis and is essential for its completion. Central spindle assembly requires the centralspindlin complex composed of the Caenorhabditis elegans ZEN-4 (mammalian orthologue MKLP1) kinesin-like protein and the Rho family GAP CYK-4 (MgcRacGAP). Here we describe a regulatory mechanism that controls the timing of central spindle assembly. The mitotic kinase Cdk1/cyclin B phosphorylates the motor domain of ZEN-4 on a conserved site within a basic amino-terminal extension characteristic of the MKLP1 subfamily. Phosphorylation by Cdk1 diminishes the motor activity of ZEN-4 by reducing its affinity for microtubules. Preventing Cdk1 phosphorylation of ZEN-4/MKLP1 causes enhanced metaphase spindle localization and defects in chromosome segregation. Thus, phosphoregulation of the motor domain of MKLP1 kinesin ensures that central spindle assembly occurs at the appropriate time in the cell cycle and maintains genomic stability.

271 citations