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Nature Apr 2023Lactate is abundant in rapidly dividing cells owing to the requirement for elevated glucose catabolism to support proliferation. However, it is not known whether...
Lactate is abundant in rapidly dividing cells owing to the requirement for elevated glucose catabolism to support proliferation. However, it is not known whether accumulated lactate affects the proliferative state. Here we use a systematic approach to determine lactate-dependent regulation of proteins across the human proteome. From these data, we identify a mechanism of cell cycle regulation whereby accumulated lactate remodels the anaphase promoting complex (APC/C). Remodelling of APC/C in this way is caused by direct inhibition of the SUMO protease SENP1 by lactate. We find that accumulated lactate binds and inhibits SENP1 by forming a complex with zinc in the SENP1 active site. SENP1 inhibition by lactate stabilizes SUMOylation of two residues on APC4, which drives UBE2C binding to APC/C. This direct regulation of APC/C by lactate stimulates timed degradation of cell cycle proteins, and efficient mitotic exit in proliferative human cells. This mechanism is initiated upon mitotic entry when lactate abundance reaches its apex. In this way, accumulation of lactate communicates the consequences of a nutrient-replete growth phase to stimulate timed opening of APC/C, cell division and proliferation. Conversely, persistent accumulation of lactate drives aberrant APC/C remodelling and can overcome anti-mitotic pharmacology via mitotic slippage. In sum, we define a biochemical mechanism through which lactate directly regulates protein function to control the cell cycle and proliferation.
Topics: Humans; Anaphase; Anaphase-Promoting Complex-Cyclosome; Cell Cycle; Cell Cycle Proteins; Lactic Acid; Mitosis
PubMed: 36921622
DOI: 10.1038/s41586-023-05939-3 -
Genes, Chromosomes & Cancer Mar 2020The anaphase-promoting complex/cyclosome (APC/C) is an E3 ubiquitin ligase that helps control chromosome separation and exit from mitosis in many different kinds of... (Review)
Review
The anaphase-promoting complex/cyclosome (APC/C) is an E3 ubiquitin ligase that helps control chromosome separation and exit from mitosis in many different kinds of organisms, including yeast, flies, worms, and humans. This review represents a new perspective on the connection between APC/C subunit mutations and cancer. The complex nature of APC/C and limited mutation analysis of its subunits has made it difficult to determine the relationship of each subunit to cancer. In this work, cancer genomic data were examined to identify APC/C subunits with a greater than 5% alteration frequency in 11 representative cancers using the cBioPortal database. Using the Genetic Determinants of Cancer Patient Survival database, APC/C subunits were also studied and found to be significantly associated with poor patient prognosis in several cases. In comparing these two kinds of cancer genomics data to published large-scale genomic analyses looking for cancer driver genes, ANAPC1 and ANAPC3/CDC27 stood out as being represented in all three types of analyses. Seven other subunits were found to be associated both with >5% alteration frequency in certain cancers and being associated with an effect on cancer patient prognosis. The aim of this review is to provide new approaches for investigators conducting in vivo studies of APC/C subunits and cancer progression. In turn, a better understanding of these APC/C subunits and their role in different cancers will help scientists design drugs that are more precisely targeted to certain cancers, using APC/C mutation status as a biomarker.
Topics: Anaphase; Anaphase-Promoting Complex-Cyclosome; Animals; Antineoplastic Agents; Humans; Mitosis; Mutation; Neoplasms; Proteasome Inhibitors; Signal Transduction
PubMed: 31652364
DOI: 10.1002/gcc.22820 -
Biochemical Society Transactions Dec 2010Two closely connected mechanisms safeguard the fidelity of chromosome segregation in eukaryotic cells. The mitotic checkpoint monitors the attachment of kinetochores to... (Review)
Review
Two closely connected mechanisms safeguard the fidelity of chromosome segregation in eukaryotic cells. The mitotic checkpoint monitors the attachment of kinetochores to microtubules and delays anaphase onset until all sister kinetochores have become attached to opposite poles. In addition, an error correction mechanism destabilizes erroneous attachments that do not lead to tension at sister kinetochores. Aurora B kinase, the catalytic subunit of the CPC (chromosomal passenger complex), acts as a sensor and effector in both pathways. In this review we focus on a poorly understood but important aspect of mitotic control: what prevents the mitotic checkpoint from springing into action when sister centromeres are split and tension is suddenly lost at anaphase onset? Recent work has shown that disjunction of sister chromatids, in principle, engages the mitotic checkpoint, and probably also the error correction mechanism, with potentially catastrophic consequences for cell division. Eukaryotic cells have solved this 'anaphase problem' by disabling the mitotic checkpoint at the metaphase-to-anaphase transition. Checkpoint inactivation is in part due to the reversal of Cdk1 (cyclin-dependent kinase 1) phosphorylation of the CPC component INCENP (inner centromere protein; Sli15 in budding yeast), which causes the relocation of the CPC from centromeres to the spindle midzone. These findings highlight principles of mitotic checkpoint control: when bipolar chromosome attachment is reached in mitosis, the checkpoint is satisfied, but still active and responsive to loss of tension. Mitotic checkpoint inactivation at anaphase onset is required to prevent checkpoint re-engagement when sister chromatids split.
Topics: Anaphase; Animals; Aurora Kinase B; Aurora Kinases; CDC2 Protein Kinase; Cell Cycle Proteins; Chromatids; Chromosome Segregation; Genes, cdc; Humans; Phosphorylation; Protein Serine-Threonine Kinases; Spindle Apparatus; Stress, Mechanical; Yeasts
PubMed: 21118144
DOI: 10.1042/BST0381660 -
Biochemical Society Transactions Oct 2011Anaphase B spindle elongation plays an important role in chromosome segregation. In the present paper, we discuss our model for anaphase B in Drosophila syncytial... (Review)
Review
Anaphase B spindle elongation plays an important role in chromosome segregation. In the present paper, we discuss our model for anaphase B in Drosophila syncytial embryos, in which spindle elongation depends on an ip (interpolar) MT (microtubule) sliding filament mechanism generated by homotetrameric kinesin-5 motors acting in concert with poleward ipMT flux, which acts as an 'on/off' switch. Specifically, the pre-anaphase B spindle is maintained at a steady-state length by the balance between ipMT sliding and ipMT depolymerization at spindle poles, producing poleward flux. Cyclin B degradation at anaphase B onset triggers: (i) an MT catastrophe gradient causing ipMT plus ends to invade the overlap zone where ipMT sliding forces are generated; and (ii) the inhibition of ipMT minus-end depolymerization so flux is turned 'off', tipping the balance of forces to allow outward ipMT sliding to push apart the spindle poles. We briefly comment on the relationship of this model to anaphase B in other systems.
Topics: Anaphase; Animals; Chromosome Segregation; Embryo, Nonmammalian; Fungi; Kinesins; Kinetochores; Microtubules; Molecular Motor Proteins; Spindle Apparatus
PubMed: 21936780
DOI: 10.1042/BST0391149 -
Molecular Biology of the Cell May 2017The spindle assembly checkpoint ensures the faithful inheritance of chromosomes by arresting mitotic progression in the presence of kinetochores that are not attached to...
The spindle assembly checkpoint ensures the faithful inheritance of chromosomes by arresting mitotic progression in the presence of kinetochores that are not attached to spindle microtubules. This is achieved through inhibition of the anaphase-promoting complex/cyclosome by a kinetochore-derived "wait anaphase" signal known as the mitotic checkpoint complex. It remains unclear whether the localization and activity of these inhibitory complexes are restricted to the mitotic spindle compartment or are diffusible throughout the cytoplasm. Here we report that "wait anaphase" signals are indeed able to diffuse outside the confines of the mitotic spindle compartment. Using a cell fusion approach to generate multinucleate cells, we investigate the effects of checkpoint signals derived from one spindle compartment on a neighboring spindle compartment. We find that spindle compartments in close proximity wait for one another to align all chromosomes before entering anaphase synchronously. Synchrony is disrupted in cells with increased interspindle distances and cellular constrictions between spindle compartments. In addition, when mitotic cells are fused with interphase cells, "wait anaphase" signals are diluted, resulting in premature mitotic exit. Overall our studies reveal that anaphase inhibitors are diffusible and active outside the confines of the mitotic spindle from which they are derived.
Topics: Anaphase; Anaphase-Promoting Complex-Cyclosome; Cell Culture Techniques; Cell Cycle Checkpoints; Cell Cycle Proteins; Humans; Kinetochores; M Phase Cell Cycle Checkpoints; Microtubules; Mitosis; Protein Serine-Threonine Kinases; Spindle Apparatus
PubMed: 28298492
DOI: 10.1091/mbc.E17-01-0036 -
Seminars in Cell & Developmental Biology Sep 2021Mitotic cell divisions ensure stable transmission of genetic information from a mother to daughter cells in a series of generations. To ensure this crucial task is... (Review)
Review
Mitotic cell divisions ensure stable transmission of genetic information from a mother to daughter cells in a series of generations. To ensure this crucial task is accomplished, the cell forms a bipolar structure called the mitotic spindle that divides sister chromatids to the opposite sides of the dividing mother cell. After successful establishment of stable attachments of microtubules to chromosomes and inspection of connections between them, at the heart of mitosis, the cell starts the process of segregation. This spectacular moment in the life of a cell is termed anaphase, and it involves two distinct processes: depolymerization of microtubules bound to chromosomes, which is also known as anaphase A, and elongation of the spindle or anaphase B. Both processes ensure physical separation of disjointed sister chromatids. In this chapter, we review the mechanisms of anaphase B spindle elongation primarily in mammalian systems, combining different pioneering ideas and concepts with more recent findings that shed new light on the force generation and regulation of biochemical modules operating during spindle elongation. Finally, we present a comprehensive model of spindle elongation that includes structural, biophysical, and molecular aspects of anaphase B.
Topics: Anaphase; Chromosome Segregation; Humans; Microtubules
PubMed: 33849764
DOI: 10.1016/j.semcdb.2021.03.023 -
Biochemical Society Transactions Feb 2015The segregation of sister chromatids during mitosis is one of the most easily visualized, yet most remarkable, events during the life cycle of a cell. The accuracy of... (Review)
Review
The segregation of sister chromatids during mitosis is one of the most easily visualized, yet most remarkable, events during the life cycle of a cell. The accuracy of this process is essential to maintain ploidy during cell duplication. Over the past 20 years, substantial progress has been made in identifying components of both the kinetochore and the mitotic spindle that generate the force to move mitotic chromosomes. Additionally, we now have a reasonable, albeit incomplete, understanding of the molecular and biochemical events that are involved in establishing and dissolving sister-chromatid cohesion. However, it is less well-understood how this dissolution of cohesion occurs synchronously on all chromosomes at the onset of anaphase. At the centre of the action is the anaphase-promoting complex/cyclosome (APC/C), an E3 ubiquitin ligase that, in association with its activator cell-division cycle protein 20 homologue (Cdc20), is responsible for the destruction of securin. This leads to the activation of separase, a specialized protease that cleaves the kleisin-subunit of the cohesin complex, to relieve cohesion between sister chromatids. APC/C-Cdc20 is also responsible for the destruction of cyclin B and therefore inactivation of the cyclin B-cyclin-dependent kinase 1 (Cdk1). This latter event induces a change in the microtubule dynamics that results in the movement of sister chromatids to spindle poles (anaphase A), spindle elongation (anaphase B) and the onset of cytokinesis. In the present paper, we review the emerging evidence that multiple, spatially and temporally regulated feedback loops ensure anaphase onset is rapid, co-ordinated and irreversible.
Topics: Anaphase; Animals; CDC2 Protein Kinase; Chromosome Segregation; Cyclin-Dependent Kinases; Humans; Kinetochores; Metaphase; Signal Transduction; Spindle Pole Bodies
PubMed: 25619242
DOI: 10.1042/BST20140250 -
Molecular Cell May 2023Cell cycle and metabolism are intimately intertwined, but how metabolites directly regulate cell-cycle machinery remains elusive. Liu et al. reveal that glycolysis...
Cell cycle and metabolism are intimately intertwined, but how metabolites directly regulate cell-cycle machinery remains elusive. Liu et al. reveal that glycolysis end-product lactate directly binds and inhibits the SUMO protease SENP1 to govern the E3 ligase activity of the anaphase-promoting complex, leading to efficient mitotic exit in proliferative cells.
Topics: Anaphase; Lactic Acid; Mitosis; Anaphase-Promoting Complex-Cyclosome; Cell Cycle Proteins
PubMed: 37207623
DOI: 10.1016/j.molcel.2023.04.013 -
Cell Cycle (Georgetown, Tex.) Oct 2021To ensure genome stability, chromosomes need to undergo proper condensation into two linked sister chromatids from prophase to prometaphase, followed by equal...
To ensure genome stability, chromosomes need to undergo proper condensation into two linked sister chromatids from prophase to prometaphase, followed by equal segregation at anaphase. Emerging evidence has shown that persistent DNA entanglements connecting the sister chromatids lead to the formation of ultrafine anaphase bridges (UFBs). If UFBs are not resolved soon after anaphase, they can induce chromosome missegregation. PICH (PLK1-interacting checkpoint helicase) is a DNA translocase that localizes on chromosome arms, centromeres and UFBs. It plays multiple essential roles in mitotic chromosome organization and segregation. PICH also recruits other associated proteins to UFBs, and together they mediate UFB resolution. Here, the proposed mechanism behind PICH's functions in chromosome organization and UFB resolution will be discussed. We summarize the regulation of PICH action at chromosome arms and centromeres, how PICH recognizes UFBs and recruits other UFB-associated factors, and finally how PICH promotes UFB resolution together with other DNA processing enzymes.
Topics: Anaphase; Centromere; Chromatids; Chromosome Segregation; Genomic Instability; Humans; Mitosis
PubMed: 34530686
DOI: 10.1080/15384101.2021.1970877 -
Cell Cycle (Georgetown, Tex.) Feb 2011Spindly is a coiled-coil domain containing protein, also known as CCDC99, that is an important regulator of the mitotic checkpoint. It belongs to a functionally... (Review)
Review
Spindly is a coiled-coil domain containing protein, also known as CCDC99, that is an important regulator of the mitotic checkpoint. It belongs to a functionally conserved family of proteins that controls the localization and function of cytoplasmic dynein at kinetochores. At kinetochores Spindly interacts with the RZZ (Rod/ZW10/Zwilch) complex and is required for the recruitment of cytoplasmic dynein to kinetochores. Loss of Spindly results in loss of kinetochore dynein functions, which impairs poleward chromosome movements and mitotic checkpoint inactivation. In addition, Spindly regulates the establishment of stable microtubule attachments via regulation of the RZZ complex. Thus, Spindly couples dynein-mediated poleward chromosome movements to the establishment of stable microtubule attachments and subsequent mitotic checkpoint inactivation and provides an important switch for the control of mitosis.
Topics: Anaphase; Animals; Carrier Proteins; Cell Cycle Proteins; Chromosomes; Dyneins; HeLa Cells; Humans; Kinetochores; Microtubules; Signal Transduction
PubMed: 21252629
DOI: 10.4161/cc.10.3.14759