The Cockayne syndrome group A and B proteins are part of a ubiquitin–proteasome degradation complex regulating cell division

Cytokinesis is monitored by a molecular machinery that promotes the degradation of the intercellular bridge, a transient protein structure connecting the two daughter cells. Here, we found that CSA and CSB, primarily defined as DNA repair factors, are located at the midbody, a transient structure in the middle of the intercellular bridge, where they recruit CUL4 and MDM2 ubiquitin ligases and the proteasome. As a part of this molecular machinery, CSA and CSB contribute to the ubiquitination and the degradation of proteins such as PRC1, the Protein Regulator of Cytokinesis, to ensure the correct separation of the two daughter cells. Defects in CSA or CSB result in perturbation of the abscission leading to the formation of long intercellular bridges and multinucleated cells, which might explain part of the Cockayne syndrome phenotypes. Our results enlighten the role played by CSA and CSB as part of a ubiquitin/proteasome degradation process involved in transcription, DNA repair, and cell division.

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Midbody: From the Regulator of Cytokinesis to Postmitotic Signaling Organelle

Medicina ◽

10.3390/medicina54040053 ◽

2018 ◽

Vol 54 (4) ◽

pp. 53 ◽

Cited By ~ 1

Author(s):

Ieva Antanavičiūtė ◽

Paulius Gibieža ◽

Rytis Prekeris ◽

Vytenis Skeberdis

Keyword(s):

Stem Cells ◽

Cell Division ◽

Intercellular Bridge ◽

Large Protein ◽

Daughter Cells ◽

First Case ◽

Tumorigenic Potential ◽

The One ◽

And Function ◽

Protein Rich

Faithful cell division is crucial for successful proliferation, differentiation, and development of cells, tissue homeostasis, and preservation of genomic integrity. Cytokinesis is a terminal stage of cell division, leaving two genetically identical daughter cells connected by an intercellular bridge (ICB) containing the midbody (MB), a large protein-rich organelle, in the middle. Cell division may result in asymmetric or symmetric abscission of the ICB. In the first case, the ICB is severed on the one side of the MB, and the MB is inherited by the opposite daughter cell. In the second case, the MB is cut from both sides, expelled into the extracellular space, and later it can be engulfed by surrounding cells. Cells with lower autophagic activity, such as stem cells and cancer stem cells, are inclined to accumulate MBs. Inherited MBs affect cell polarity, modulate intra- and intercellular communication, enhance pluripotency of stem cells, and increase tumorigenic potential of cancer cells. In this review, we briefly summarize the latest knowledge on MB formation, inheritance, degradation, and function, and in addition, present and discuss our recent findings on the electrical and chemical communication of cells connected through the MB-containing ICB.

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Fascetto interacting protein ensures proper cytokinesis and ploidy

Molecular Biology of the Cell ◽

10.1091/mbc.e18-09-0573 ◽

2019 ◽

Vol 30 (8) ◽

pp. 992-1007 ◽

Cited By ~ 1

Author(s):

Zachary T. Swider ◽

Rachel K. Ng ◽

Ramya Varadarajan ◽

Carey J. Fagerstrom ◽

Nasser M. Rusan

Keyword(s):

Cell Division ◽

Tissue Repair ◽

Complete Separation ◽

Contractile Ring ◽

Interacting Protein ◽

Simultaneous Reduction ◽

Central Spindle ◽

Daughter Cells ◽

Molecular Machinery ◽

The Brain

Cell division is critical for development, organ growth, and tissue repair. The later stages of cell division include the formation of the microtubule (MT)-rich central spindle in anaphase, which is required to properly define the cell equator, guide the assembly of the acto-myosin contractile ring and ultimately ensure complete separation and isolation of the two daughter cells via abscission. Much is known about the molecular machinery that forms the central spindle, including proteins needed to generate the antiparallel overlapping interzonal MTs. One critical protein that has garnered great attention is the protein regulator of cytokinesis 1, or Fascetto (Feo) in Drosophila, which forms a homodimer to cross-link interzonal MTs, ensuring proper central spindle formation and cytokinesis. Here, we report on a new direct protein interactor and regulator of Feo we named Feo interacting protein (FIP). Loss of FIP results in a reduction in Feo localization, rapid disassembly of interzonal MTs, and several defects related to cytokinesis failure, including polyploidization of neural stem cells. Simultaneous reduction in Feo and FIP results in very large, tumorlike DNA-filled masses in the brain that contain hundreds of centrosomes. In aggregate, our data show that FIP acts directly on Feo to ensure fully accurate cell division.

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Extrachromosomal Histone H2B Contributes to the Formation of the Abscission Site for Cell Division

Cells ◽

10.3390/cells8111391 ◽

2019 ◽

Vol 8 (11) ◽

pp. 1391 ◽

Cited By ~ 1

Author(s):

Laura Monteonofrio ◽

Davide Valente ◽

Cinzia Rinaldo ◽

Silvia Soddu

Keyword(s):

Cell Division ◽

Chromatin Structure ◽

Late Stage ◽

Intercellular Bridge ◽

Histone H2b ◽

Physical Separation ◽

Daughter Cells ◽

Dna And Rna ◽

Constitutive Components

Histones are constitutive components of nucleosomes and key regulators of chromatin structure. We previously observed that an extrachromosomal histone H2B (ecH2B) localizes at the intercellular bridge (ICB) connecting the two daughter cells during cytokinesis independently of DNA and RNA. Here, we show that ecH2B binds and colocalizes with CHMP4B, a key component of the ESCRT-III machinery responsible for abscission, the final step of cell division. Abscission requires the formation of an abscission site at the ICB where the ESCRT-III complex organizes into narrowing cortical helices that drive the physical separation of sibling cells. ecH2B depletion does not prevent membrane cleavage rather results in abscission delay and accumulation of abnormally long and thin ICBs. In the absence of ecH2B, CHMP4B and other components of the fission machinery, such as IST1 and Spastin, are recruited to the ICB and localize at the midbody. However, in the late stage of abscission, these fission factors fail to re-localize at the periphery of the midbody and the abscission site fails to form. These results show that extrachromosomal activity of histone H2B is required in the formation of the abscission site and the proper localization of the fission machinery.

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Partitioning and Exocytosis of Secretory Granules during Division of PC12 Cells

International Journal of Cell Biology ◽

10.1155/2012/805295 ◽

2012 ◽

Vol 2012 ◽

pp. 1-14 ◽

Cited By ~ 4

Author(s):

Nickolay Vassilev Bukoreshtliev ◽

Erlend Hodneland ◽

Tilo Wolf Eichler ◽

Patricia Eifart ◽

Amin Rustom ◽

...

Keyword(s):

Cell Division ◽

Pc12 Cells ◽

Secretory Granules ◽

Time Lapse ◽

Intercellular Bridge ◽

Time Lapse Microscopy ◽

Interphase Cells ◽

Molecular Machinery ◽

Spindle Microtubules ◽

Single Granule

The biogenesis, maturation, and exocytosis of secretory granules in interphase cells have been well documented, whereas the distribution and exocytosis of these hormone-storing organelles during cell division have received little attention. By combining ultrastructural analyses and time-lapse microscopy, we here show that, in dividing PC12 cells, the prominent peripheral localization of secretory granules is retained during prophase but clearly reduced during prometaphase, ending up with only few peripherally localized secretory granules in metaphase cells. During anaphase and telophase, secretory granules exhibited a pronounced movement towards the cell midzone and, evidently, their tracks colocalized with spindle microtubules. During cytokinesis, secretory granules were excluded from the midbody and accumulated at the bases of the intercellular bridge. Furthermore, by measuring exocytosis at the single granule level, we showed, that during all stages of cell division, secretory granules were competent for regulated exocytosis. In conclusion, our data shed new light on the complex molecular machinery of secretory granule redistribution during cell division, which facilitates their release from the F-actin-rich cortex and active transport along spindle microtubules.

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Secreted midbody remnants are a class of extracellular vesicles molecularly distinct from exosomes and microparticles

Communications Biology ◽

10.1038/s42003-021-01882-z ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Alin Rai ◽

David W. Greening ◽

Rong Xu ◽

Maoshan Chen ◽

Wittaya Suwakulsiri ◽

...

Keyword(s):

Cell Division ◽

Large Scale ◽

Cellular Transformation ◽

Extracellular Vesicle ◽

Colon Cancer Cells ◽

Intercellular Bridge ◽

Extracellular Medium ◽

Daughter Cells ◽

Biochemical Characterisation ◽

Sister Cells

AbstractDuring the final stages of cell division, newly-formed daughter cells remain connected by a thin intercellular bridge containing the midbody (MB), a microtubule-rich organelle responsible for cytokinetic abscission. Following cell division the MB is asymmetrically inherited by one daughter cell where it persists as a midbody remnant (MB-R). Accumulating evidence shows MB-Rs are secreted (sMB-Rs) into the extracellular medium and engulfed by neighbouring non-sister cells. While much is known about intracellular MB-Rs, sMB-Rs are poorly understood. Here, we report the large-scale purification and biochemical characterisation of sMB-Rs released from colon cancer cells, including profiling of their proteome using mass spectrometry. We show sMB-Rs are an abundant class of membrane-encapsulated extracellular vesicle (200-600 nm) enriched in core cytokinetic proteins and molecularly distinct from exosomes and microparticles. Functional dissection of sMB-Rs demonstrated that they are engulfed by, and accumulate in, quiescent fibroblasts where they promote cellular transformation and an invasive phenotype.

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Fascetto Interacting Protein (FIP) Regulates Fascetto (PRC1) to Ensure Proper Cytokinesis and Ploidy

10.1101/413997 ◽

2018 ◽

Author(s):

Zachary T. Swider ◽

Rachel K. Ng ◽

Ramya Varadarajan ◽

Carey J. Fagerstrom ◽

Nasser M Rusan

Keyword(s):

Cell Division ◽

Tissue Repair ◽

Complete Separation ◽

Contractile Ring ◽

Interacting Protein ◽

Simultaneous Reduction ◽

Central Spindle ◽

Daughter Cells ◽

Molecular Machinery ◽

The Brain

AbstractCell division is critical for development, organ growth, and tissue repair. The later stages of cell division include the formation of the microtubule (MT)-rich central spindle in anaphase, which is required to properly define the cell equator, guide the assembly of the acto-myosin contractile ring, and ultimately ensure complete separation and isolation of the two daughter cells via abscission. Much is known about the molecular machinery that forms the central spindle, including proteins needed to generate the antiparallel overlapping interzonal MTs. One critical protein that has garnered great attention is Protein Regulator of Cytokinesis 1 (PRC1), or Fascetto (Feo) in Drosophila, which forms a homodimer to crosslink interzonal MTs, ensuring proper central spindle formation and cytokinesis. Here, we report on a new direct protein interactor and regulator of Feo we named Fascetto Interacting Protein (FIP). Loss of FIP results in a significant reduction in Feo localization, rapid disassembly of interzonal MTs, and several cytokinesis defects. Simultaneous reduction in Feo and FIP results in tumor-like, DNA-filled masses in the brain. In aggregate our data show that FIP functions upstream of, and acts directly on, Feo to ensure fully accurate cell division.

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Chromokinesin KIF4A teams up with stathmin 1 to regulate abscission in a SUMO-dependent manner

Journal of Cell Science ◽

10.1242/jcs.248591 ◽

2020 ◽

Vol 133 (14) ◽

pp. jcs248591

Author(s):

Sabine A. G. Cuijpers ◽

Edwin Willemstein ◽

Jan G. Ruppert ◽

Daphne M. van Elsland ◽

William C. Earnshaw ◽

...

Keyword(s):

Cell Division ◽

Acceptor Site ◽

Dependent Manner ◽

Intercellular Bridge ◽

Dynamic Interactions ◽

Post Translational Modifications ◽

Sumo Modification ◽

Daughter Cells ◽

Sumo Conjugation ◽

Stathmin 1

ABSTRACTCell division ends when two daughter cells physically separate via abscission, the cleavage of the intercellular bridge. It is not clear how the anti-parallel microtubule bundles bridging daughter cells are severed. Here, we present a novel abscission mechanism. We identified chromokinesin KIF4A, which is adjacent to the midbody during cytokinesis, as being required for efficient abscission. KIF4A is regulated by post-translational modifications. We evaluated modification of KIF4A by the ubiquitin-like protein SUMO. We mapped lysine 460 in KIF4A as the SUMO acceptor site and employed CRISPR-Cas9-mediated genome editing to block SUMO conjugation of endogenous KIF4A. Failure to SUMOylate this site in KIF4A delayed cytokinesis. SUMOylation of KIF4A enhanced the affinity for the microtubule destabilizer stathmin 1 (STMN1). We here present a new level of abscission regulation through the dynamic interactions between KIF4A and STMN1 as controlled by SUMO modification of KIF4A.

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Alpha 6 integrins promote cytokinesis by regulating the expression of RSK2 and MKLP1

10.1101/830562 ◽

2019 ◽

Author(s):

Neetu Singh ◽

Hao Xu ◽

Renee Thiemann ◽

Kara A. DeSantis ◽

Melinda Larsen ◽

...

Keyword(s):

Cell Division ◽

Normal Development ◽

Intercellular Bridge ◽

S6 Kinase ◽

Cellular Processes ◽

Daughter Cells ◽

Cytoplasmic Material ◽

Ribosomal S6 Kinase 2 ◽

Ribosomal S6 Kinase ◽

Salivary Gland Epithelial Cells

ABSTRACTThe integrin-mediated interaction of cells with components of the extracellular matrix (ECM) regulates many cellular processes including cell division. Cytokinesis is the last step of cell division and is critical for normal development and tissue homeostasis as it ensures the proper segregation of genetic and cytoplasmic material between daughter cells. Cytokinesis failure leads to defects in development and tissue differentiation, as well as tumorigenesis. Abscission of intercellular bridge that connects presumptive daughter cells is the last step of cell division. The mitotic kinesin-like protein 1 (MKLP1) plays a central role in positioning the abscission machinery. Here, we show that α6 integrins promote successful cytokinesis in salivary gland epithelial cells by regulating the expression of MKLP1. RNAi-mediated depletion of α6 integrins inhibits cytokinesis and the expression of MKLP1 and p90 ribosomal-S6-kinase 2 (RSK2). Depletion of RSK2 results in similar defects in cytokinesis and also inhibits the expression of MKLP1, suggesting that the expression of RSK2 is required downstream of integrins to promote MKLP1 expression and successful cytokinesis. RNAi-mediated depletion of RSK2 in embryonic salivary glands in organ culture also results in the inhibition of cytokinesis and MKLP1 expression, indicating the physiological significance of this pathway.

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ALIX and ESCRT-I/II function as parallel ESCRT-III recruiters in cytokinetic abscission

The Journal of Cell Biology ◽

10.1083/jcb.201507009 ◽

2016 ◽

Vol 212 (5) ◽

pp. 499-513 ◽

Cited By ~ 75

Author(s):

Liliane Christ ◽

Eva M. Wenzel ◽

Knut Liestøl ◽

Camilla Raiborg ◽

Coen Campsteijn ◽

...

Keyword(s):

Cell Division ◽

Final Stage ◽

Binding Protein ◽

Intercellular Bridge ◽

Checkpoint Signaling ◽

Endosomal Sorting ◽

Daughter Cells ◽

Escrt Machinery ◽

Chromosome Bridges ◽

In Cells

Cytokinetic abscission, the final stage of cell division where the two daughter cells are separated, is mediated by the endosomal sorting complex required for transport (ESCRT) machinery. The ESCRT-III subunit CHMP4B is a key effector in abscission, whereas its paralogue, CHMP4C, is a component in the abscission checkpoint that delays abscission until chromatin is cleared from the intercellular bridge. How recruitment of these components is mediated during cytokinesis remains poorly understood, although the ESCRT-binding protein ALIX has been implicated. Here, we show that ESCRT-II and the ESCRT-II–binding ESCRT-III subunit CHMP6 cooperate with ESCRT-I to recruit CHMP4B, with ALIX providing a parallel recruitment arm. In contrast to CHMP4B, we find that recruitment of CHMP4C relies predominantly on ALIX. Accordingly, ALIX depletion leads to furrow regression in cells with chromosome bridges, a phenotype associated with abscission checkpoint signaling failure. Collectively, our work reveals a two-pronged recruitment of ESCRT-III to the cytokinetic bridge and implicates ALIX in abscission checkpoint signaling.

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Use of cell doublets for studying cytokinesis regulation reveals a new form of cytokinesis regression

10.21203/rs.3.rs-730080/v1 ◽

2021 ◽

Author(s):

◽

Einat Panet ◽

Shira Huri Ohev Shalom ◽

Ohad Kraus ◽

Irit Shoval ◽

...

Keyword(s):

Cell Division ◽

Mitotic Spindle ◽

Protein Phosphatase ◽

Protein Phosphatase 1 ◽

Intercellular Bridge ◽

Microtubule Network ◽

Aurora Kinases ◽

Daughter Cells ◽

Chemical Inhibition ◽

Chromatin Bridges

Abstract Cytokinesis mediates separation of daughter cells at the end of cell division. We have developed a high-throughput approach for monitoring cell-autonomous cytokinesis in non-adherent cells. Focusing on cytokinesis termination, we show that chemical inhibition of protein phosphatase 1 (PP1) and PP2A specifically in late cytokinesis activates cytokinesis regression, which is distinct from any known cytokinesis failure, and is not a by-product of abnormal furrow ingression or chromatin bridges. This process is characterized by the formation of cortical blebs primarily at the intercellular bridge, reopening of the cleavage furrow and reassembly of an interphase-like microtubule network, but not by chromatin recondensation and mitotic spindle formation. Finally, cytokinesis regression is suppressed by chemical inhibition of aurora kinases but not Cdk1 or PLK1. Altogether, our results highlight a hitherto uncharacterized facet of the counter-activity of PP1/PP2A and aurora kinases in the final step of cell division, which ultimately secure the conclusion of cytokinesis, thereby preventing polyploidy and genomic instability.

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