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Zhang Y, Wang ZZ, Han AQ, Yang MY, Zhu LX, Pan FM, Wang Y. TuBG1 promotes hepatocellular carcinoma via ATR/P53-apoptosis and cycling pathways. Hepatobiliary Pancreat Dis Int 2024; 23:195-209. [PMID: 37806848 DOI: 10.1016/j.hbpd.2023.09.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Accepted: 09/19/2023] [Indexed: 10/10/2023]
Abstract
BACKGROUND As reported, γ-tubulin (TuBG1) is related to the occurrence and development of various types of malignant tumors. However, its role in hepatocellular cancer (HCC) is not clear. The present study was to investigate the relationship between TuBG1 and clinical parameters and survival in HCC patients. METHODS The correlation between TuBG1 and clinical parameters and survival in HCC patients was explored by bioinformatics analysis. Immunohistochemistry was used for the verification. The molecular function of TuBG1 was measured using colony formation, scratch assay, trans-well assay and flow cytometry. Gene set enrichment analysis (GSEA) was used to pick up the enriched pathways, followed by investigating the target pathways using Western blotting. The tumor-immune system interactions and drug bank database (TISIDB) was used to evaluate TuBG1 and immunity. Based on the TuBG1-related immune genes, a prognostic model was constructed and was further validated internally and externally. RESULTS The bioinformatic analysis found high expressed TuBG1 in HCC tissue, which was confirmed using immunohistochemistry and Western blotting. After silencing the TuBG1 in HCC cell lines, more G1 arrested cells were found, cell proliferation and invasion were inhibited, and apoptosis was promoted. Furthermore, the silence of TuBG1 increased the expressions of Ataxia-Telangiectasia and Rad-3 (ATR), phospho-P38 mitogen-activated protein kinase (P-P38MAPK), phospho-P53 (P-P53), B-cell lymphoma-2 associated X protein (Bax), cleaved caspase 3 and P21; decreased the expressions of B-cell lymphoma-2 (Bcl-2), cyclin D1, cyclin E2, cyclin-dependent kinase 2 (CDK2) and CDK4. The correlation analysis of immunohistochemistry and clinical parameters and survival data revealed that TuBG1 was negatively correlated with the overall survival. The constructed immune prognosis model could effectively evaluate the prognosis. CONCLUSIONS The increased expression of TuBG1 in HCC is associated with poor prognosis, which might be involved in the occurrence and development of HCC.
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Affiliation(s)
- Yan Zhang
- Department of General Surgery, The Second Hospital of Anhui Medical University, Hefei 230601, China
| | - Zhen-Zhen Wang
- Department of General Surgery, The First Affiliated Hospital of Anhui Medical University, Hefei 230022, China
| | - An-Qi Han
- Department of General Surgery, The First Affiliated Hospital of Anhui Medical University, Hefei 230022, China
| | - Ming-Ya Yang
- Department of General Surgery, The First Affiliated Hospital of Anhui Medical University, Hefei 230022, China
| | - Li-Xin Zhu
- Department of General Surgery, The First Affiliated Hospital of Anhui Medical University, Hefei 230022, China
| | - Fa-Ming Pan
- Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, Hefei 230032, China; The Key Laboratory of Major Autoimmune Diseases, Anhui Medical University, Hefei 230032, China
| | - Yong Wang
- Department of General Surgery, The Second Hospital of Anhui Medical University, Hefei 230601, China.
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2
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Bloomfield M, Cimini D. The fate of extra centrosomes in newly formed tetraploid cells: should I stay, or should I go? Front Cell Dev Biol 2023; 11:1210983. [PMID: 37576603 PMCID: PMC10413984 DOI: 10.3389/fcell.2023.1210983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Accepted: 07/17/2023] [Indexed: 08/15/2023] Open
Abstract
An increase in centrosome number is commonly observed in cancer cells, but the role centrosome amplification plays along with how and when it occurs during cancer development is unclear. One mechanism for generating cancer cells with extra centrosomes is whole genome doubling (WGD), an event that occurs in over 30% of human cancers and is associated with poor survival. Newly formed tetraploid cells can acquire extra centrosomes during WGD, and a generally accepted model proposes that centrosome amplification in tetraploid cells promotes cancer progression by generating aneuploidy and chromosomal instability. Recent findings, however, indicate that newly formed tetraploid cells in vitro lose their extra centrosomes to prevent multipolar cell divisions. Rather than persistent centrosome amplification, this evidence raises the possibility that it may be advantageous for tetraploid cells to initially restore centrosome number homeostasis and for a fraction of the population to reacquire additional centrosomes in the later stages of cancer evolution. In this review, we explore the different evolutionary paths available to newly formed tetraploid cells, their effects on centrosome and chromosome number distribution in daughter cells, and their probabilities of long-term survival. We then discuss the mechanisms that may alter centrosome and chromosome numbers in tetraploid cells and their relevance to cancer progression following WGD.
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Affiliation(s)
- Mathew Bloomfield
- Department of Biological Sciences and Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA, United States
| | - Daniela Cimini
- Department of Biological Sciences and Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA, United States
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3
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Sulimenko V, Dráberová E, Dráber P. γ-Tubulin in microtubule nucleation and beyond. Front Cell Dev Biol 2022; 10:880761. [PMID: 36158181 PMCID: PMC9503634 DOI: 10.3389/fcell.2022.880761] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Accepted: 08/03/2022] [Indexed: 11/13/2022] Open
Abstract
Microtubules composed of αβ-tubulin dimers are dynamic cytoskeletal polymers that play key roles in essential cellular processes such as cell division, organelle positioning, intracellular transport, and cell migration. γ-Tubulin is a highly conserved member of the tubulin family that is required for microtubule nucleation. γ-Tubulin, together with its associated proteins, forms the γ-tubulin ring complex (γ-TuRC), that templates microtubules. Here we review recent advances in the structure of γ-TuRC, its activation, and centrosomal recruitment. This provides new mechanistic insights into the molecular mechanism of microtubule nucleation. Accumulating data suggest that γ-tubulin also has other, less well understood functions. We discuss emerging evidence that γ-tubulin can form oligomers and filaments, has specific nuclear functions, and might be involved in centrosomal cross-talk between microtubules and microfilaments.
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Affiliation(s)
| | | | - Pavel Dráber
- *Correspondence: Vadym Sulimenko, ; Pavel Dráber,
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4
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Kim JM. Molecular Link between DNA Damage Response and Microtubule Dynamics. Int J Mol Sci 2022; 23:ijms23136986. [PMID: 35805981 PMCID: PMC9266319 DOI: 10.3390/ijms23136986] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 06/20/2022] [Accepted: 06/21/2022] [Indexed: 11/16/2022] Open
Abstract
Microtubules are major components of the cytoskeleton that play important roles in cellular processes such as intracellular transport and cell division. In recent years, it has become evident that microtubule networks play a role in genome maintenance during interphase. In this review, we highlight recent advances in understanding the role of microtubule dynamics in DNA damage response and repair. We first describe how DNA damage checkpoints regulate microtubule organization and stability. We then highlight how microtubule networks are involved in the nuclear remodeling following DNA damage, which leads to changes in chromosome organization. Lastly, we discuss how microtubule dynamics participate in the mobility of damaged DNA and promote consequent DNA repair. Together, the literature indicates the importance of microtubule dynamics in genome organization and stability during interphase.
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Affiliation(s)
- Jung Min Kim
- Department of Pharmacology, Chonnam National University Medical School, Gwangju 58128, Korea
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5
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Tingler M, Philipp M, Burkhalter MD. DNA Replication proteins in primary microcephaly syndromes. Biol Cell 2022; 114:143-159. [PMID: 35182397 DOI: 10.1111/boc.202100061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 01/28/2022] [Accepted: 01/31/2022] [Indexed: 11/30/2022]
Abstract
SCOPE Improper expansion of neural stem and progenitor cells during brain development manifests in primary microcephaly. It is characterized by a reduced head circumference, which correlates with a reduction in brain size. This often corresponds to a general underdevelopment of the brain and entails cognitive, behavioral and motoric retardation. In the past decade significant research efforts have been undertaken to identify genes and the molecular mechanisms underlying microcephaly. One such gene set encompasses factors required for DNA replication. Intriguingly, a growing body of evidence indicates that a substantial number of these genes mediate faithful centrosome and cilium function in addition to their canonical function in genome duplication. Here, we summarize, which DNA replication factors are associated with microcephaly syndromes and to which extent they impact on centrosomes and cilia. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Melanie Tingler
- Department of Experimental and Clinical Pharmacology and Pharmacogenomics, Section of Pharmacogenomics, Eberhard-Karls-University Tübingen, Tübingen, 72074, Germany
| | - Melanie Philipp
- Department of Experimental and Clinical Pharmacology and Pharmacogenomics, Section of Pharmacogenomics, Eberhard-Karls-University Tübingen, Tübingen, 72074, Germany
| | - Martin D Burkhalter
- Department of Experimental and Clinical Pharmacology and Pharmacogenomics, Section of Pharmacogenomics, Eberhard-Karls-University Tübingen, Tübingen, 72074, Germany
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6
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Floriot S, Bellutti L, Castille J, Moison P, Messiaen S, Passet B, Boulanger L, Boukadiri A, Tourpin S, Beauvallet C, Vilotte M, Riviere J, Péchoux C, Bertaud M, Vilotte JL, Livera G. CEP250 is Required for Maintaining Centrosome Cohesion in the Germline and Fertility in Male Mice. Front Cell Dev Biol 2022; 9:754054. [PMID: 35127699 PMCID: PMC8809461 DOI: 10.3389/fcell.2021.754054] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 12/24/2021] [Indexed: 12/02/2022] Open
Abstract
Male gametogenesis involves both mitotic divisions to amplify germ cell progenitors that gradually differentiate and meiotic divisions. Centrosomal regulation is essential for both types of divisions, with centrioles remaining tightly paired during the interphase. Here, we generated and characterized the phenotype of mutant mice devoid of Cep250/C-Nap1, a gene encoding for a docking protein for fibers linking centrioles, and characterized their phenotype. The Cep250-/- mice presented with no major defects, apart from male infertility due to a reduction in the spermatogonial pool and the meiotic blockade. Spermatogonial stem cells expressing Zbtb16 were not affected, whereas the differentiating spermatogonia were vastly lost. These cells displayed abnormal γH2AX-staining, accompanied by an increase in the apoptotic rate. The few germ cells that survived at this stage, entered the meiotic prophase I and were arrested at a pachytene-like stage, likely due to synapsis defects and the unrepaired DNA double-strand breaks. In these cells, centrosomes split up precociously, with γ-tubulin foci being separated whereas these were closely associated in wild-type cells. Interestingly, this lack of cohesion was also observed in wild-type female meiocytes, likely explaining the normal fertility of Cep250-/- female mice. Taken together, this study proposes a specific requirement of centrosome cohesion in the male germline, with a crucial role of CEP250 in both differentiating spermatogonia and meiotic spermatocytes.
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Affiliation(s)
- Sandrine Floriot
- INRAe, AgroParisTech, Université Paris-Saclay, GABI, Jouy-en-Josas, France
| | - Laura Bellutti
- Laboratory of Development of the Gonads, UMRE008 Genetic Stability Stem Cells and Radiations, IRCM/IBFJ CEA, Université de Paris, Université Paris-Saclay, Paris, France
- *Correspondence: Laura Bellutti, ; Gabriel Livera,
| | - Johan Castille
- INRAe, AgroParisTech, Université Paris-Saclay, GABI, Jouy-en-Josas, France
| | - Pauline Moison
- Laboratory of Development of the Gonads, UMRE008 Genetic Stability Stem Cells and Radiations, IRCM/IBFJ CEA, Université de Paris, Université Paris-Saclay, Paris, France
| | - Sébastien Messiaen
- Laboratory of Development of the Gonads, UMRE008 Genetic Stability Stem Cells and Radiations, IRCM/IBFJ CEA, Université de Paris, Université Paris-Saclay, Paris, France
| | - Bruno Passet
- INRAe, AgroParisTech, Université Paris-Saclay, GABI, Jouy-en-Josas, France
| | - Laurent Boulanger
- INRAe, AgroParisTech, Université Paris-Saclay, GABI, Jouy-en-Josas, France
| | - Abdelhak Boukadiri
- INRAe, AgroParisTech, Université Paris-Saclay, GABI, Jouy-en-Josas, France
| | - Sophie Tourpin
- Laboratory of Development of the Gonads, UMRE008 Genetic Stability Stem Cells and Radiations, IRCM/IBFJ CEA, Université de Paris, Université Paris-Saclay, Paris, France
| | | | - Marthe Vilotte
- INRAe, AgroParisTech, Université Paris-Saclay, GABI, Jouy-en-Josas, France
| | - Julie Riviere
- INRAe, AgroParisTech, Université Paris-Saclay, GABI, Jouy-en-Josas, France
| | - Christine Péchoux
- INRAe, AgroParisTech, Université Paris-Saclay, GABI, Jouy-en-Josas, France
| | - Maud Bertaud
- INRAe, AgroParisTech, Université Paris-Saclay, GABI, Jouy-en-Josas, France
| | - Jean-Luc Vilotte
- INRAe, AgroParisTech, Université Paris-Saclay, GABI, Jouy-en-Josas, France
| | - Gabriel Livera
- Laboratory of Development of the Gonads, UMRE008 Genetic Stability Stem Cells and Radiations, IRCM/IBFJ CEA, Université de Paris, Université Paris-Saclay, Paris, France
- *Correspondence: Laura Bellutti, ; Gabriel Livera,
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7
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Dráber P, Dráberová E. Dysregulation of Microtubule Nucleating Proteins in Cancer Cells. Cancers (Basel) 2021; 13:cancers13225638. [PMID: 34830792 PMCID: PMC8616210 DOI: 10.3390/cancers13225638] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 11/06/2021] [Accepted: 11/08/2021] [Indexed: 12/12/2022] Open
Abstract
Simple Summary The dysfunction of microtubule nucleation in cancer cells changes the overall cytoskeleton organization and cellular physiology. This review focuses on the dysregulation of the γ-tubulin ring complex (γ-TuRC) proteins that are essential for microtubule nucleation. Recent research on the high-resolution structure of γ-TuRC has brought new insight into the microtubule nucleation mechanism. We discuss the effect of γ-TuRC protein overexpression on cancer cell behavior and new drugs directed to γ-tubulin that may offer a viable alternative to microtubule-targeting agents currently used in cancer chemotherapy. Abstract In cells, microtubules typically nucleate from microtubule organizing centers, such as centrosomes. γ-Tubulin, which forms multiprotein complexes, is essential for nucleation. The γ-tubulin ring complex (γ-TuRC) is an efficient microtubule nucleator that requires additional centrosomal proteins for its activation and targeting. Evidence suggests that there is a dysfunction of centrosomal microtubule nucleation in cancer cells. Despite decades of molecular analysis of γ-TuRC and its interacting factors, the mechanisms of microtubule nucleation in normal and cancer cells remains obscure. Here, we review recent work on the high-resolution structure of γ-TuRC, which brings new insight into the mechanism of microtubule nucleation. We discuss the effects of γ-TuRC protein dysregulation on cancer cell behavior and new compounds targeting γ-tubulin. Drugs inhibiting γ-TuRC functions could represent an alternative to microtubule targeting agents in cancer chemotherapy.
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8
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Primary cilia and the DNA damage response: linking a cellular antenna and nuclear signals. Biochem Soc Trans 2021; 49:829-841. [PMID: 33843966 DOI: 10.1042/bst20200751] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 03/09/2021] [Accepted: 03/10/2021] [Indexed: 11/17/2022]
Abstract
The maintenance of genome stability involves integrated biochemical activities that detect DNA damage or incomplete replication, delay the cell cycle, and direct DNA repair activities on the affected chromatin. These processes, collectively termed the DNA damage response (DDR), are crucial for cell survival and to avoid disease, particularly cancer. Recent work has highlighted links between the DDR and the primary cilium, an antenna-like, microtubule-based signalling structure that extends from a centriole docked at the cell surface. Ciliary dysfunction gives rise to a range of complex human developmental disorders termed the ciliopathies. Mutations in ciliopathy genes have been shown to impact on several functions that relate to centrosome integrity, DNA damage signalling, responses to problems in DNA replication and the control of gene expression. This review covers recent findings that link cilia and the DDR and explores the various roles played by key genes in these two contexts. It outlines how proteins encoded by ciliary genes impact checkpoint signalling, DNA replication and repair, gene expression and chromatin remodelling. It discusses how these diverse activities may integrate nuclear responses with those that affect a structure of the cell periphery. Additional directions for exploration of the interplay between these pathways are highlighted, with a focus on new ciliary gene candidates that alter genome stability.
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9
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Drosophila female germline stem cells undergo mitosis without nuclear breakdown. Curr Biol 2021; 31:1450-1462.e3. [PMID: 33548191 DOI: 10.1016/j.cub.2021.01.033] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 11/18/2020] [Accepted: 01/11/2021] [Indexed: 02/02/2023]
Abstract
Stem cell homeostasis requires nuclear lamina (NL) integrity. In Drosophila germ cells, compromised NL integrity activates the ataxia telangiectasia and Rad3-related (ATR) and checkpoint kinase 2 (Chk2) checkpoint kinases, blocking germ cell differentiation and causing germline stem cell (GSC) loss. Checkpoint activation occurs upon loss of either the NL protein emerin or its partner barrier-to-autointegration factor, two proteins required for nuclear reassembly at the end of mitosis. Here, we examined how mitosis contributes to NL structural defects linked to checkpoint activation. These analyses led to the unexpected discovery that wild-type female GSCs utilize a non-canonical mode of mitosis, one that retains a permeable but intact nuclear envelope and NL. We show that the interphase NL is remodeled during mitosis for insertion of centrosomes that nucleate the mitotic spindle within the confines of the nucleus. We show that depletion or loss of NL components causes mitotic defects, including compromised chromosome segregation associated with altered centrosome positioning and structure. Further, in emerin mutant GSCs, centrosomes remain embedded in the interphase NL. Notably, these embedded centrosomes carry large amounts of pericentriolar material and nucleate astral microtubules, revealing a role for emerin in the regulation of centrosome structure. Epistasis studies demonstrate that defects in centrosome structure are upstream of checkpoint activation, suggesting that these centrosome defects might trigger checkpoint activation and GSC loss. Connections between NL proteins and centrosome function have implications for mechanisms associated with NL dysfunction in other stem cell populations, including NL-associated diseases, such as laminopathies.
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10
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Molinuevo R, Freije A, Contreras L, Sanz JR, Gandarillas A. The DNA damage response links human squamous proliferation with differentiation. J Cell Biol 2020; 219:152154. [PMID: 33007086 PMCID: PMC7534927 DOI: 10.1083/jcb.202001063] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 05/08/2020] [Accepted: 08/14/2020] [Indexed: 12/26/2022] Open
Abstract
How rapid cell multiplication leads to cell differentiation in developing tissues is still enigmatic. This question is central to morphogenesis, cell number control, and homeostasis. Self-renewal epidermoid epithelia are continuously exposed to mutagens and are the most common target of cancer. Unknown mechanisms commit rapidly proliferating cells to post-mitotic terminal differentiation. We have over-activated or inhibited the endogenous DNA damage response (DDR) pathways by combinations of activating TopBP1 protein, specific shRNAs, or chemical inhibitors for ATR, ATM, and/or DNA-PK. The results dissect and demonstrate that these signals control keratinocyte differentiation in proliferating cells independently of actual DNA damage. The DDR limits keratinocyte multiplication upon hyperproliferative stimuli. Moreover, knocking down H2AX, a common target of the DDR pathways, inhibits the epidermoid phenotype. The results altogether show that the DDR is required to maintain the balance proliferation differentiation and suggest that is part of the squamous program. We propose a homeostatic model where genetic damage is automatically and continuously cleansed by cell-autonomous mechanisms.
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Affiliation(s)
- Rut Molinuevo
- Cell Cycle, Stem Cell Fate and Cancer Laboratory, Institute for Research Marqués de Valdecilla, Santander, Spain
| | - Ana Freije
- Cell Cycle, Stem Cell Fate and Cancer Laboratory, Institute for Research Marqués de Valdecilla, Santander, Spain
| | - Lizbeth Contreras
- Cell Cycle, Stem Cell Fate and Cancer Laboratory, Institute for Research Marqués de Valdecilla, Santander, Spain
| | - Juan R Sanz
- Cell Cycle, Stem Cell Fate and Cancer Laboratory, Institute for Research Marqués de Valdecilla, Santander, Spain.,Plastic Surgery Service, Hospital Universitario Marqués de Valdecilla, Santander, Spain.,Plastic Surgery Department, Universidad de Cantabria, Santander, Spain
| | - Alberto Gandarillas
- Cell Cycle, Stem Cell Fate and Cancer Laboratory, Institute for Research Marqués de Valdecilla, Santander, Spain.,Institut National de la Santé et de la Recherche Médicale, Languedoc-Roussillon, Montpellier, France
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Corvaisier M, Alvarado-Kristensson M. Non-Canonical Functions of the Gamma-Tubulin Meshwork in the Regulation of the Nuclear Architecture. Cancers (Basel) 2020; 12:cancers12113102. [PMID: 33114224 PMCID: PMC7690915 DOI: 10.3390/cancers12113102] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 10/17/2020] [Accepted: 10/21/2020] [Indexed: 12/15/2022] Open
Abstract
Simple Summary The appearance of a cell is connected to its function. For example, the fusiform of smooth muscle cells is adapted to facilitate muscle contraction, the lobed nucleus in white blood cells assists with the migratory behavior of these immune cells, and the condensed nucleus in sperm aids in their swimming efficiency. Thus, changes in appearance have been used for decades by doctors as a diagnostic method for human cancers. Here, we summarize our knowledge of how a cell maintains the shape of the nuclear compartment. Specifically, we discuss the role of a novel protein meshwork, the gamma-tubulin meshwork, in the regulation of nuclear morphology and as a therapeutic target against cancer. Abstract The nuclear architecture describes the organization of the various compartments in the nucleus of eukaryotic cells, where a plethora of processes such as nucleocytoplasmic transport, gene expression, and assembly of ribosomal subunits occur in a dynamic manner. During the different phases of the cell cycle, in post-mitotic cells and after oncogenic transformation, rearrangements of the nuclear architecture take place, and, among other things, these alterations result in reorganization of the chromatin and changes in gene expression. A member of the tubulin family, γtubulin, was first identified as part of a multiprotein complex that allows nucleation of microtubules. However, more than a decade ago, γtubulin was also characterized as a nuclear protein that modulates several crucial processes that affect the architecture of the nucleus. This review presents the latest knowledge regarding changes that arise in the nuclear architecture of healthy cells and under pathological conditions and, more specifically, considers the particular involvement of γtubulin in the modulation of the biology of the nuclear compartment.
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12
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Movsisyan N, Pardo LA. Kv10.1 Regulates Microtubule Dynamics during Mitosis. Cancers (Basel) 2020; 12:cancers12092409. [PMID: 32854244 PMCID: PMC7564071 DOI: 10.3390/cancers12092409] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 08/13/2020] [Accepted: 08/18/2020] [Indexed: 12/16/2022] Open
Abstract
Kv10.1 (potassium voltage-gated channel subfamily H member 1, known as EAG1 or Ether-à-go-go 1), is a voltage-gated potassium channel, prevailingly expressed in the central nervous system. The aberrant expression of Kv10.1 is detected in over 70% of all human tumor tissues and correlates with poorer prognosis. In peripheral tissues, Kv10.1 is expressed almost exclusively during the G2/M phase of the cell cycle and regulates its progression-downregulation of Kv10.1 extends the duration of the G2/M phase both in cancer and healthy cells. Here, using biochemical and imaging techniques, such as live-cell measurements of microtubule growth and of cytosolic calcium, we elucidate the mechanisms of Kv10.1-mediated regulation at the G2/M phase. We show that Kv10.1 has a dual effect on mitotic microtubule dynamics. Through the functional interaction with ORAI1 (calcium release-activated calcium channel protein 1), it modulates cytosolic calcium oscillations, thereby changing microtubule behavior. The inhibition of either Kv10.1 or ORAI1 stabilizes the microtubules. In contrast, the knockdown of Kv10.1 increases the dynamicity of mitotic microtubules, resulting in a stronger spindle assembly checkpoint, greater mitotic spindle angle, and a decrease in lagging chromosomes. Understanding of Kv10.1-mediated modulation of the microtubule architecture will help to comprehend how cancer tissue benefits from the presence of Kv10.1, and thereby increase the efficacy and safety of Kv10.1-directed therapeutic strategies.
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13
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Hiregange D, Naick H, Rao BJ. ATR signalling mediates the prosurvival function of phospho-NPM against PIDDosome mediated cell death. Cell Signal 2020; 71:109602. [DOI: 10.1016/j.cellsig.2020.109602] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Accepted: 03/14/2020] [Indexed: 12/14/2022]
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14
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Wilhelm T, Said M, Naim V. DNA Replication Stress and Chromosomal Instability: Dangerous Liaisons. Genes (Basel) 2020; 11:E642. [PMID: 32532049 PMCID: PMC7348713 DOI: 10.3390/genes11060642] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 06/04/2020] [Accepted: 06/08/2020] [Indexed: 12/16/2022] Open
Abstract
Chromosomal instability (CIN) is associated with many human diseases, including neurodevelopmental or neurodegenerative conditions, age-related disorders and cancer, and is a key driver for disease initiation and progression. A major source of structural chromosome instability (s-CIN) leading to structural chromosome aberrations is "replication stress", a condition in which stalled or slowly progressing replication forks interfere with timely and error-free completion of the S phase. On the other hand, mitotic errors that result in chromosome mis-segregation are the cause of numerical chromosome instability (n-CIN) and aneuploidy. In this review, we will discuss recent evidence showing that these two forms of chromosomal instability can be mechanistically interlinked. We first summarize how replication stress causes structural and numerical CIN, focusing on mechanisms such as mitotic rescue of replication stress (MRRS) and centriole disengagement, which prevent or contribute to specific types of structural chromosome aberrations and segregation errors. We describe the main outcomes of segregation errors and how micronucleation and aneuploidy can be the key stimuli promoting inflammation, senescence, or chromothripsis. At the end, we discuss how CIN can reduce cellular fitness and may behave as an anticancer barrier in noncancerous cells or precancerous lesions, whereas it fuels genomic instability in the context of cancer, and how our current knowledge may be exploited for developing cancer therapies.
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Affiliation(s)
- Therese Wilhelm
- CNRS UMR9019 Genome Integrity and Cancers, Université Paris Saclay, Gustave Roussy, 94805 Villejuif, France; (T.W.); (M.S.)
- UMR144 Cell Biology and Cancer, Institut Curie, 75005 Paris, France
| | - Maha Said
- CNRS UMR9019 Genome Integrity and Cancers, Université Paris Saclay, Gustave Roussy, 94805 Villejuif, France; (T.W.); (M.S.)
| | - Valeria Naim
- CNRS UMR9019 Genome Integrity and Cancers, Université Paris Saclay, Gustave Roussy, 94805 Villejuif, France; (T.W.); (M.S.)
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15
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Alvarado-Kristensson M. Choreography of the centrosome. Heliyon 2020; 6:e03238. [PMID: 31989056 PMCID: PMC6970175 DOI: 10.1016/j.heliyon.2020.e03238] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2019] [Revised: 01/10/2020] [Accepted: 01/13/2020] [Indexed: 12/31/2022] Open
Abstract
More than a century ago, the centrosome was discovered and described as “the true division organ of the cell”. Electron microscopy revealed that a centrosome is an amorphous structure or pericentriolar protein matrix that surrounds a pair of well-organized centrioles. Today, the importance of the centrosome as a microtubule-organizing center and coordinator of the mitotic spindle is questioned, because centrioles are absent in up to half of all known eukaryotic species, and various mechanisms for acentrosomal microtubule nucleation have been described. This review recapitulates the known functions of centrosome movements in cellular homeostasis and discusses knowledge gaps in this field.
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Affiliation(s)
- Maria Alvarado-Kristensson
- Molecular Pathology, Department of Translational Medicine, Lund University, Skåne University Hospital, Malmö, SE-20502, Sweden
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16
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Jin H, Zhang Y, Liu D, Wang SS, Ding Q, Rastogi P, Purvis M, Wang A, Elhadi S, Ren C, Cao C, Chai Y, Igarashi P, Jetten AM, Lu D, Attanasio M. Innate Immune Signaling Contributes to Tubular Cell Senescence in the Glis2 Knockout Mouse Model of Nephronophthisis. THE AMERICAN JOURNAL OF PATHOLOGY 2020; 190:176-189. [PMID: 31676329 PMCID: PMC6943802 DOI: 10.1016/j.ajpath.2019.09.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 08/27/2019] [Accepted: 09/04/2019] [Indexed: 01/20/2023]
Abstract
Nephronophthisis (NPHP), the leading genetic cause of end-stage renal failure in children and young adults, is a group of autosomal recessive diseases characterized by kidney-cyst degeneration and fibrosis for which no therapy is currently available. To date, mutations in >25 genes have been identified as causes of this disease that, in several cases, result in chronic DNA damage in kidney tubular cells. Among such mutations, those in the transcription factor-encoding GLIS2 cause NPHP type 7. Loss of function of mouse Glis2 causes senescence of kidney tubular cells. Senescent cells secrete proinflammatory molecules that induce progressive organ damage through several pathways, among which NF-κB signaling is prevalent. Herein, we show that the NF-κB signaling is active in Glis2 knockout kidney epithelial cells and that genetic inactivation of the toll-like receptor (TLR)/IL-1 receptor or pharmacologic elimination of senescent cells (senolytic therapy) reduces tubule damage, fibrosis, and apoptosis in the Glis2 mouse model of NPHP. Notably, in Glis2, Tlr2 double knockouts, senescence was also reduced and proliferation was increased, suggesting that loss of TLR2 activity improves the regenerative potential of tubular cells in Glis2 knockout kidneys. Our results further suggest that a combination of TLR/IL-1 receptor inhibition and senolytic therapy may delay the progression of kidney disease in NPHP type 7 and other forms of this disease.
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Affiliation(s)
- Heng Jin
- Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa; Department of Emergency Medicine, Tianjin Medical University General Hospital, Tianjin, China
| | - Yan Zhang
- Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa; Department of Emergency Medicine, Tianjin Medical University General Hospital, Tianjin, China
| | - Dingxiao Liu
- Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa; Department of Vascular Surgery, Second Xiangya Hospital, Central South University, Changsha, China
| | - Shan Shanshan Wang
- Department of Hepatic Oncology, Liver Cancer Institute, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Qiong Ding
- Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Prerna Rastogi
- Department of Pathology, University of Iowa, Iowa City, Iowa
| | - Madison Purvis
- Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Angela Wang
- Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Sarah Elhadi
- Division of Neprhology, Children's Hospital of Illinois, Peoria, Illinois
| | - Chongyu Ren
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Chao Cao
- Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa; Department of Emergency Medicine, Tianjin Medical University General Hospital, Tianjin, China
| | - Yanfen Chai
- Department of Emergency Medicine, Tianjin Medical University General Hospital, Tianjin, China
| | - Peter Igarashi
- Department of Internal Medicine, University of Minnesota, Minneapolis, Minnesota
| | - Anton M Jetten
- Cell Biology Section, Division of Intramural Research, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, North Carolina
| | - Dongmei Lu
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Massimo Attanasio
- Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa.
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17
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Potter H, Chial HJ, Caneus J, Elos M, Elder N, Borysov S, Granic A. Chromosome Instability and Mosaic Aneuploidy in Neurodegenerative and Neurodevelopmental Disorders. Front Genet 2019; 10:1092. [PMID: 31788001 PMCID: PMC6855267 DOI: 10.3389/fgene.2019.01092] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 10/09/2019] [Indexed: 12/15/2022] Open
Abstract
Evidence from multiple laboratories has accumulated to show that mosaic neuronal aneuploidy and consequent apoptosis characterizes and may underlie neuronal loss in many neurodegenerative diseases, particularly Alzheimer’s disease and frontotemporal dementia. Furthermore, several neurodevelopmental disorders, including Seckel syndrome, ataxia telangiectasia, Nijmegen breakage syndrome, Niemann–Pick type C, and Down syndrome, have been shown to also exhibit mosaic aneuploidy in neurons in the brain and in other cells throughout the body. Together, these results indicate that both neurodegenerative and neurodevelopmental disorders with apparently different pathogenic causes share a cell cycle defect that leads to mosaic aneuploidy in many cell types. When such mosaic aneuploidy arises in neurons in the brain, it promotes apoptosis and may at least partly underlie the cognitive deficits that characterize the neurological symptoms of these disorders. These findings have implications for both diagnosis and treatment/prevention.
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Affiliation(s)
- Huntington Potter
- Department of Neurology, Rocky Mountain Alzheimer's Disease Center, University of Colorado, Aurora, CO, United States.,Linda Crnic Institute for Down Syndrome, University of Colorado, Aurora, CO, United States
| | - Heidi J Chial
- Department of Neurology, Rocky Mountain Alzheimer's Disease Center, University of Colorado, Aurora, CO, United States.,Linda Crnic Institute for Down Syndrome, University of Colorado, Aurora, CO, United States
| | - Julbert Caneus
- NanoScience Technology Center, University of Central Florida, Orlando, FL, United States
| | - Mihret Elos
- Department of Neurology, Rocky Mountain Alzheimer's Disease Center, University of Colorado, Aurora, CO, United States.,Linda Crnic Institute for Down Syndrome, University of Colorado, Aurora, CO, United States
| | - Nina Elder
- Department of Neurology, Rocky Mountain Alzheimer's Disease Center, University of Colorado, Aurora, CO, United States.,Linda Crnic Institute for Down Syndrome, University of Colorado, Aurora, CO, United States
| | - Sergiy Borysov
- Department of Math and Science, Saint Leo University, Saint Leo, FL, United States
| | - Antoneta Granic
- AGE Research Group, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom.,Newcastle University Institute for Ageing, NIHR Newcastle Biomedical Research Centre, Newcastle upon Tyne, United Kingdom.,Newcastle upon Tyne Hospitals, NHS Foundation Trust, Newcastle upon Tyne, United Kingdom
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18
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Nai S, Shi Y, Ru H, Ding Y, Geng Q, Li Z, Dong MQ, Xu X, Li J. Chk2-dependent phosphorylation of myosin phosphatase targeting subunit 1 (MYPT1) regulates centrosome maturation. Cell Cycle 2019; 18:2651-2659. [PMID: 31416392 PMCID: PMC6773232 DOI: 10.1080/15384101.2019.1654795] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 07/17/2019] [Accepted: 08/07/2019] [Indexed: 12/16/2022] Open
Abstract
Checkpoint kinase 2 (Chk2) is a pivotal effector kinase in the DNA damage response, with an emerging role in mitotic chromosome segregation. In this study, we show that Chk2 interacts with myosin phosphatase targeting subunit 1 (MYPT1), the targeting subunit of protein phosphatase 1cβ (PP1cβ). Previous studies have shown that MYPT1 is phosphorylated by CDK1 at S473 during mitosis, and subsequently docks to the polo-binding domain of PLK1 and dephosphorylates PLK1. Herein we present data that Chk2 phosphorylates MYPT1 at S507 in vitro and in vivo, which antagonizes pS473. Chk2 inhibition results in failure of γ-tubulin recruitment to the centrosomes, phenocopying Plk1 inhibition defects. These aberrancies were also observed in the MYPT1-S507A stable transfectants, suggesting that Chk2 exerts its effect on centrosomes via MYPT1. Collectively, we have identified a Chk2-MYPT1-PLK1 axis in regulating centrosome maturation. Abbreviations: Chk2: checkpoint kinase 2; MYPT1: myosin phosphatase targeting subunit 1; PP1cβ: protein phosphatase 1c β; Noc: nocodazole; IP: immunoprecipitation; IB: immunoblotting; LC-MS/MS: liquid chromatography-tandem mass spectrometry; Chk2: checkpoint kinase 2; KD: kinase domain; WT: wild type; Ub: ubiquitin; DAPI: 4',6-diamidino-2-phenylindole; IF: Immunofluorescence; IR: ionizing radiation; siCHK2: siRNA targeting CHK2.
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Affiliation(s)
- Shanshan Nai
- Beijing Key Laboratory of DNA damage Response, College of Life Sciences, Capital Normal University, Beijing, China
| | - Yingxin Shi
- Beijing Key Laboratory of DNA damage Response, College of Life Sciences, Capital Normal University, Beijing, China
| | - Huanwei Ru
- Beijing Key Laboratory of DNA damage Response, College of Life Sciences, Capital Normal University, Beijing, China
| | - Yuehe Ding
- National Institute of Biological Sciences, Beijing, China
| | - Qizhi Geng
- Beijing Key Laboratory of DNA damage Response, College of Life Sciences, Capital Normal University, Beijing, China
| | - Zhe Li
- Beijing Key Laboratory of DNA damage Response, College of Life Sciences, Capital Normal University, Beijing, China
| | - Meng-Qiu Dong
- National Institute of Biological Sciences, Beijing, China
| | - Xingzhi Xu
- Beijing Key Laboratory of DNA damage Response, College of Life Sciences, Capital Normal University, Beijing, China
- Guangdong Key Laboratory of Genome Stability & Disease Prevention, Shenzhen University School of Medicine, Shenzhen, China
| | - Jing Li
- Beijing Key Laboratory of DNA damage Response, College of Life Sciences, Capital Normal University, Beijing, China
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19
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Abstract
DNA repair proteins have been found to localize to the centrosomes and defects in these proteins cause centrosome abnormality. Centrobin is a centriole-associated protein that is required for centriole duplication and microtubule stability. A recent study revealed that centrobin is a candidate substrate for ATM/ATR kinases. However, whether centrobin is involved in DNA damage response (DDR) remains unexplored. Here we show that centrobin is phosphorylated after UV exposure and that the phosphorylation is detected exclusively in the detergent/DNase I-resistant nuclear matrix. UV-induced phosphorylation of centrobin is largely dependent on ATR activity. Centrobin-depleted cells show impaired DNA damage-induced microtubule stabilization and increased sensitivity to UV radiation. Interestingly, depletion of centrobin leads to defective homologous recombination (HR) repair, which is reversed by expression of wild-type centrobin. Taken together, these results strongly suggest that centrobin plays an important role in DDR.
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Affiliation(s)
- Na Mi Ryu
- Department of Pharmacology, Chonnam National University Medical School , Jellanamdo , Republic of Korea
| | - Jung Min Kim
- Department of Pharmacology, Chonnam National University Medical School , Jellanamdo , Republic of Korea
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20
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Chumová J, Kourová H, Trögelová L, Halada P, Binarová P. Microtubular and Nuclear Functions of γ-Tubulin: Are They LINCed? Cells 2019; 8:cells8030259. [PMID: 30893853 PMCID: PMC6468392 DOI: 10.3390/cells8030259] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 03/07/2019] [Accepted: 03/14/2019] [Indexed: 01/02/2023] Open
Abstract
γ-Tubulin is a conserved member of the tubulin superfamily with a function in microtubule nucleation. Proteins of γ-tubulin complexes serve as nucleation templates as well as a majority of other proteins contributing to centrosomal and non-centrosomal nucleation, conserved across eukaryotes. There is a growing amount of evidence of γ-tubulin functions besides microtubule nucleation in transcription, DNA damage response, chromatin remodeling, and on its interactions with tumor suppressors. However, the molecular mechanisms are not well understood. Furthermore, interactions with lamin and SUN proteins of the LINC complex suggest the role of γ-tubulin in the coupling of nuclear organization with cytoskeletons. γ-Tubulin that belongs to the clade of eukaryotic tubulins shows characteristics of both prokaryotic and eukaryotic tubulins. Both human and plant γ-tubulins preserve the ability of prokaryotic tubulins to assemble filaments and higher-order fibrillar networks. γ-Tubulin filaments, with bundling and aggregating capacity, are suggested to perform complex scaffolding and sequestration functions. In this review, we discuss a plethora of γ-tubulin molecular interactions and cellular functions, as well as recent advances in understanding the molecular mechanisms behind them.
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Affiliation(s)
- Jana Chumová
- Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic.
| | - Hana Kourová
- Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic.
| | - Lucie Trögelová
- Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic.
| | - Petr Halada
- Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic.
| | - Pavla Binarová
- Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic.
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21
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Verification and rectification of cell type-specific splicing of a Seckel syndrome-associated ATR mutation using iPS cell model. J Hum Genet 2019; 64:445-458. [PMID: 30846821 PMCID: PMC8075875 DOI: 10.1038/s10038-019-0574-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 12/25/2018] [Accepted: 01/18/2019] [Indexed: 11/08/2022]
Abstract
Seckel syndrome (SS) is a rare spectrum of congenital severe microcephaly and dwarfism. One SS-causative gene is Ataxia Telangiectasia and Rad3-Related Protein (ATR), and ATR (c.2101 A>G) mutation causes skipping of exon 9, resulting in a hypomorphic ATR defect. This mutation is considered the cause of an impaired response to DNA replication stress, the main function of ATR, contributing to the pathogenesis of microcephaly. However, the precise behavior and impact of this splicing defect in human neural progenitor cells (NPCs) is unclear. To address this, we established induced pluripotent stem cells (iPSCs) from fibroblasts carrying the ATR mutation and an isogenic ATR-corrected counterpart iPSC clone. SS-patient-derived iPSCs (SS-iPSCs) exhibited cell type-specific splicing; exon 9 was dominantly skipped in fibroblasts and iPSC-derived NPCs, but it was included in undifferentiated iPSCs and definitive endodermal cells. SS-iPSC-derived NPCs (SS-NPCs) showed distinct expression profiles from ATR non-mutated NPCs with negative enrichment of neuronal genesis-related gene sets. In SS-NPCs, abnormal mitotic spindles occurred more frequently than in gene-corrected counterparts, and the alignment of NPCs in the surface of the neurospheres was perturbed. Finally, we tested several splicing-modifying compounds and found that TG003, a CLK1 inhibitor, could pharmacologically rescue the exon 9 skipping in SS-NPCs. Treatment with TG003 restored the ATR kinase activity in SS-NPCs and decreased the frequency of abnormal mitotic events. In conclusion, our iPSC model revealed a novel effect of the ATR mutation in mitotic processes of NPCs and NPC-specific missplicing, accompanied by the recovery of neuronal defects using a splicing rectifier.
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22
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Sethy R, Rakesh R, Patne K, Arya V, Sharma T, Haokip DT, Kumari R, Muthuswami R. Regulation of ATM and ATR by SMARCAL1 and BRG1. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2018; 1861:1076-1092. [PMID: 30317028 DOI: 10.1016/j.bbagrm.2018.10.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 10/03/2018] [Accepted: 10/06/2018] [Indexed: 11/25/2022]
Abstract
The G2/M checkpoint is activated on DNA damage by the ATM and ATR kinases that are regulated by post-translational modifications. In this paper, the transcriptional co-regulation of ATM and ATR by SMARCAL1 and BRG1, both members of the ATP-dependent chromatin remodeling protein family, is described. SMARCAL1 and BRG1 co-localize on the promoters of ATM and ATR; downregulation of SMARCAL1 and BRG1 results in transcriptional repression of ATM/ATR and overriding of the G2/M checkpoint leading to mitotic abnormalities. On doxorubicin-induced DNA damage, SMARCAL1 and BRG1 are upregulated and these two proteins in turn, upregulate the expression of ATM/ATR. The transcriptional response to DNA damage is feedback regulated by phospho-ATM as it binds to the promoters of SMARCAL1, BRG1, ATM and ATR on DNA damage. The regulation of ATM/ATR is rendered non-functional in Schimke Immuno-Osseous Dysplasia where SMARCAL1 is mutated and in Coffin-Siris Syndrome where BRG1 is mutated. Thus, an intricate transcriptional regulation of DNA damage response genes mediated by SMARCAL1 and BRG1 is present in mammalian cells.
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Affiliation(s)
| | | | - Ketki Patne
- School of Life Sciences, JNU, New Delhi, India
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23
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Alvarado-Kristensson M. γ-tubulin as a signal-transducing molecule and meshwork with therapeutic potential. Signal Transduct Target Ther 2018; 3:24. [PMID: 30221013 PMCID: PMC6137058 DOI: 10.1038/s41392-018-0021-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Revised: 04/23/2018] [Accepted: 05/06/2018] [Indexed: 01/05/2023] Open
Abstract
Knowledge of γ-tubulin is increasing with regard to the cellular functions of this protein beyond its participation in microtubule nucleation. γ-Tubulin expression is altered in various malignancies, and changes in the TUBG1 gene have been found in patients suffering from brain malformations. This review recapitulates the known functions of γ-tubulin in cellular homeostasis and discusses the possible influence of the protein on disease development and cancer.
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Affiliation(s)
- Maria Alvarado-Kristensson
- Molecular Pathology, Department of Translational Medicine, Lund University, Skåne University Hospital, Malmö, 20502 Sweden
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24
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Bond MJ, Bleiler M, Harrison LE, Scocchera EW, Nakanishi M, G-Dayanan N, Keshipeddy S, Rosenberg DW, Wright DL, Giardina C. Spindle Assembly Disruption and Cancer Cell Apoptosis with a CLTC-Binding Compound. Mol Cancer Res 2018; 16:1361-1372. [PMID: 29769406 DOI: 10.1158/1541-7786.mcr-18-0178] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 04/05/2018] [Accepted: 04/25/2018] [Indexed: 11/16/2022]
Abstract
AK3 compounds are mitotic arrest agents that induce high levels of γH2AX during mitosis and apoptosis following release from arrest. We synthesized a potent AK3 derivative, AK306, that induced arrest and apoptosis of the HCT116 colon cancer cell line with an EC50 of approximately 50 nmol/L. AK306 was active on a broad spectrum of cancer cell lines with total growth inhibition values ranging from approximately 25 nmol/L to 25 μmol/L. Using biotin and BODIPY-linked derivatives of AK306, binding to clathrin heavy chain (CLTC/CHC) was observed, a protein with roles in endocytosis and mitosis. AK306 inhibited mitosis and endocytosis, while disrupting CHC cellular localization. Cells arrested in mitosis by AK306 showed the formation of multiple microtubule-organizing centers consisting of pericentrin, γ-tubulin, and Aurora A foci, without apparent centrosome amplification. Cells released from AK306 arrest were unable to form bipolar spindles, unlike nocodazole-released cells that reformed spindles and completed division. Like AK306, CHC siRNA knockdown disrupted spindle formation and activated p53. A short-term (3-day) treatment of tumor-bearing APC-mutant mice with AK306 increased apoptosis in tumors, but not normal mucosa. These findings indicate that targeting the mitotic CHC complex can selectively induce apoptosis and may have therapeutic value.Implication: Disruption of clathrin with a small-molecule inhibitor, AK306, selectively induces apoptosis in cancer cells by disrupting bipolar spindle formation. Mol Cancer Res; 16(9); 1361-72. ©2018 AACR.
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Affiliation(s)
- Michael J Bond
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, Connecticut.,Department of Pharmacology, Yale University, New Haven, Connecticut
| | - Marina Bleiler
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, Connecticut
| | - Lauren E Harrison
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, Connecticut
| | - Eric W Scocchera
- Department of Medicinal Chemistry, University of Connecticut, Storrs, Connecticut
| | - Masako Nakanishi
- Center for Molecular Oncology, UConn Health, Farmington, Connecticut
| | - Narendran G-Dayanan
- Department of Medicinal Chemistry, University of Connecticut, Storrs, Connecticut
| | - Santosh Keshipeddy
- Department of Medicinal Chemistry, University of Connecticut, Storrs, Connecticut
| | | | - Dennis L Wright
- Department of Medicinal Chemistry, University of Connecticut, Storrs, Connecticut
| | - Charles Giardina
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, Connecticut.
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25
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Romano FJ, Guadagno E, Solari D, Borrelli G, Pignatiello S, Cappabianca P, Del Basso De Caro M. ATM and p53 combined analysis predicts survival in glioblastoma multiforme patients: A clinicopathologic study. J Cell Biochem 2018; 119:4867-4877. [PMID: 29369420 DOI: 10.1002/jcb.26699] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Accepted: 01/23/2018] [Indexed: 12/19/2022]
Abstract
Glioblastoma is one of the most malignant cancers, with a distinguishing dismal prognosis: surgery followed by chemo- and radiotherapy represents the current standard of care, and chemo- and radioresistance underlie disease recurrence and short overall survival of patients suffering from this malignancy. ATM is a kinase activated by autophosphorylation upon DNA doublestrand breaks arising from errors during replication, byproducts of metabolism, chemotherapy or ionizing radiations; TP53 is one of the most popular tumor suppressor, with a preeminent role in DNA damage response and repair. To study the effects of the immunohistochemical expression of p-ATM and p53 in glioblastoma patients, 21 cases were retrospectively examined. In normal brain tissue, p-ATM was expressed only in neurons; conversely, in tumors cells, the protein showed a variable cytoplasmic expression (score: +,++,+++), with being completely undetectable in three cases. Statistical analysis revealed that high p-ATM score (++/+++) strongly correlated to shorter survival (P = 0.022). No difference in overall survival was registered between p53 normally expressed (NE) and overexpressed (OE) glioblastoma patients (P = 0.669). Survival analysis performed on the results from combined assessment of the two proteins showed that patients with NE p53 /low pATM score had longer overall survival than the NE p53/ high pATM score counterpart. Cox-regression analysis confirmed this finding (HR = 0.025; CI 95% = 0.002-0.284; P = 0.003). Our study outlined the immunohistochemical expression of p-ATM/p53 in glioblastomas and provided data on their possible prognostic/predictive of response role. A "non-oncogene addiction" to ATM for NEp53 glioblastoma could be postulated, strengthening the rationale for development of ATM inhibiting drugs.
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Affiliation(s)
| | - Elia Guadagno
- Department of Advanced Biomedical Sciences, Pathology Section, Division of Neurosurgery - University of Naples Federico II, Naples, Italy
| | - Domenico Solari
- Department of Neurosciences, Reproductive and Odontostomatological Sciences, Division of Neurosurgery - University of Naples Federico II, Naples, Italy
| | - Giorgio Borrelli
- Department of Advanced Biomedical Sciences, Pathology Section, Division of Neurosurgery - University of Naples Federico II, Naples, Italy
| | - Sara Pignatiello
- Department of Advanced Biomedical Sciences, Pathology Section, Division of Neurosurgery - University of Naples Federico II, Naples, Italy
| | - Paolo Cappabianca
- Department of Neurosciences, Reproductive and Odontostomatological Sciences, Division of Neurosurgery - University of Naples Federico II, Naples, Italy
| | - Marialaura Del Basso De Caro
- Department of Advanced Biomedical Sciences, Pathology Section, Division of Neurosurgery - University of Naples Federico II, Naples, Italy
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26
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Lu D, Rauhauser A, Li B, Ren C, McEnery K, Zhu J, Chaki M, Vadnagara K, Elhadi S, Jetten AM, Igarashi P, Attanasio M. Loss of Glis2/NPHP7 causes kidney epithelial cell senescence and suppresses cyst growth in the Kif3a mouse model of cystic kidney disease. Kidney Int 2017; 89:1307-23. [PMID: 27181777 DOI: 10.1016/j.kint.2016.03.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Revised: 02/12/2016] [Accepted: 03/03/2016] [Indexed: 01/27/2023]
Abstract
Enlargement of kidney tubules is a common feature of multiple cystic kidney diseases in humans and mice. However, while some of these pathologies are characterized by cyst expansion and organ enlargement, in others, progressive interstitial fibrosis and kidney atrophy prevail. The Kif3a knockout mouse is an established non-orthologous mouse model of cystic kidney disease. Conditional inactivation of Kif3a in kidney tubular cells results in loss of primary cilia and rapid cyst growth. Conversely, loss of function of the gene GLIS2/NPHP7 causes progressive kidney atrophy, interstitial inflammatory infiltration, and fibrosis. Kif3a null tubular cells have unrestrained proliferation and reduced stabilization of p53 resulting in a loss of cell cycle arrest in the presence of DNA damage. In contrast, loss of Glis2 is associated with activation of checkpoint kinase 1, stabilization of p53, and induction of cell senescence. Interestingly, the cystic phenotype of Kif3a knockout mice is partially rescued by genetic ablation of Glis2 and pharmacological stabilization of p53. Thus, Kif3a is required for cell cycle regulation and the DNA damage response, whereas cell senescence is significantly enhanced in Glis2 null cells. Hence, cell senescence is a central feature in nephronophthisis type 7 and Kif3a is unexpectedly required for efficient DNA damage response and cell cycle arrest.
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Affiliation(s)
- Dongmei Lu
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Alysha Rauhauser
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Binghua Li
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Chongyu Ren
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Kayla McEnery
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Jili Zhu
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA; Department of Nephrology, Renmin Hospital, Wuhan University, Wuhan, Hubei, China
| | - Moumita Chaki
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Komal Vadnagara
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Sarah Elhadi
- Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Anton M Jetten
- Cell Biology Section, Division of Intramural Research, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, USA
| | - Peter Igarashi
- Department of Internal Medicine, University of Minnesota, Minneapolis, MN, USA
| | - Massimo Attanasio
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA; Eugene McDermott Center for Growth and Development, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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Walz G. Role of primary cilia in non-dividing and post-mitotic cells. Cell Tissue Res 2017; 369:11-25. [PMID: 28361305 PMCID: PMC5487853 DOI: 10.1007/s00441-017-2599-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 02/20/2017] [Accepted: 02/27/2017] [Indexed: 12/12/2022]
Abstract
The essential role of primary (non-motile) cilia during the development of multi-cellular tissues and organs is well established and is underlined by severe disease manifestations caused by mutations in cilia-associated molecules that are collectively termed ciliopathies. However, the role of primary cilia in non-dividing and terminally differentiated, post-mitotic cells is less well understood. Although the prevention of cells from re-entering the cell cycle may represent a major chore, primary cilia have recently been linked to DNA damage responses, autophagy and mitochondria. Given this connectivity, primary cilia in non-dividing cells are well positioned to form a signaling hub outside of the nucleus. Such a center could integrate information to initiate responses and to maintain cellular homeostasis if cell survival is jeopardized. These more discrete functions may remain undetected until differentiated cells are confronted with emergencies.
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Affiliation(s)
- Gerd Walz
- Renal Division, Department of Medicine, University Freiburg Medical Center, Hugstetter Strasse 55, 79106, Freiburg, Germany.
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28
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Abstract
Here, we review how DNA damage affects the centrosome and how centrosomes communicate with the DNA damage response (DDR) apparatus. We discuss how several proteins of the DDR are found at centrosomes, including the ATM, ATR, CHK1 and CHK2 kinases, the BRCA1 ubiquitin ligase complex and several members of the poly(ADP-ribose) polymerase family. Stereotypical centrosome organisation, in which two centriole barrels are orthogonally arranged in a roughly toroidal pericentriolar material (PCM), is strongly affected by exposure to DNA-damaging agents. We describe the genetic dependencies and mechanisms for how the centrioles lose their close association, and the PCM both expands and distorts after DNA damage. Another consequence of genotoxic stress is that centrosomes undergo duplication outside the normal cell cycle stage, meaning that centrosome amplification is commonly seen after DNA damage. We discuss several potential mechanisms for how centrosome numbers become dysregulated after DNA damage and explore the links between the DDR and the PLK1- and separase-dependent mechanisms that drive centriole separation and reduplication. We also describe how centrosome components, such as centrin2, are directly involved in responding to DNA damage. This review outlines current questions on the involvement of centrosomes in the DDR.
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Affiliation(s)
- Lisa I Mullee
- Centre for Chromosome Biology, School of Natural Sciences, National University of Ireland Galway, Biosciences Building, Dangan, Galway, Ireland
| | - Ciaran G Morrison
- Centre for Chromosome Biology, School of Natural Sciences, National University of Ireland Galway, Biosciences Building, Dangan, Galway, Ireland.
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29
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Hoang-Minh LB, Deleyrolle LP, Nakamura NS, Parker AK, Martuscello RT, Reynolds BA, Sarkisian MR. PCM1 Depletion Inhibits Glioblastoma Cell Ciliogenesis and Increases Cell Death and Sensitivity to Temozolomide. Transl Oncol 2016; 9:392-402. [PMID: 27661404 PMCID: PMC5035360 DOI: 10.1016/j.tranon.2016.08.006] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 08/08/2016] [Accepted: 08/12/2016] [Indexed: 01/09/2023] Open
Abstract
A better understanding of the molecules implicated in the growth and survival of glioblastoma (GBM) cells and their response to temozolomide (TMZ), the standard-of-care chemotherapeutic agent, is necessary for the development of new therapies that would improve the outcome of current GBM treatments. In this study, we characterize the role of pericentriolar material 1 (PCM1), a component of centriolar satellites surrounding centrosomes, in GBM cell proliferation and sensitivity to genotoxic agents such as TMZ. We show that PCM1 is expressed around centrioles and ciliary basal bodies in patient GBM biopsies and derived cell lines and that its localization is dynamic throughout the cell cycle. To test whether PCM1 mediates GBM cell proliferation and/or response to TMZ, we used CRISPR/Cas9 genome editing to generate primary GBM cell lines depleted of PCM1. These PCM1-depleted cells displayed reduced AZI1 satellite protein localization and significantly decreased proliferation, which was attributable to increased apoptotic cell death. Furthermore, PCM1-depleted lines were more sensitive to TMZ toxicity than control lines. The increase in TMZ sensitivity may be partly due to the reduced ability of PCM1-depleted cells to form primary cilia, as depletion of KIF3A also ablated GBM cells' ciliogenesis and increased their sensitivity to TMZ while preserving PCM1 localization. In addition, the co-depletion of KIF3A and PCM1 did not have any additive effect on TMZ sensitivity. Together, our data suggest that PCM1 plays multiple roles in GBM pathogenesis and that associated pathways could be targeted to augment current or future anti-GBM therapies.
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Affiliation(s)
- Lan B Hoang-Minh
- Department of Neuroscience, University of Florida College of Medicine, McKnight Brain Institute, Gainesville, FL 32610, USA; Preston A. Wells, Jr. Center for Brain Tumor Therapy, University of Florida College of Medicine, McKnight Brain Institute, Gainesville, FL 32610, USA
| | - Loic P Deleyrolle
- Preston A. Wells, Jr. Center for Brain Tumor Therapy, University of Florida College of Medicine, McKnight Brain Institute, Gainesville, FL 32610, USA; Department of Neurosurgery, University of Florida College of Medicine, McKnight Brain Institute, Gainesville, FL 32610, USA
| | - Nariaki S Nakamura
- Department of Neuroscience, University of Florida College of Medicine, McKnight Brain Institute, Gainesville, FL 32610, USA
| | - Alexander K Parker
- Department of Neuroscience, University of Florida College of Medicine, McKnight Brain Institute, Gainesville, FL 32610, USA
| | - Regina T Martuscello
- Preston A. Wells, Jr. Center for Brain Tumor Therapy, University of Florida College of Medicine, McKnight Brain Institute, Gainesville, FL 32610, USA; Department of Neurosurgery, University of Florida College of Medicine, McKnight Brain Institute, Gainesville, FL 32610, USA
| | - Brent A Reynolds
- Preston A. Wells, Jr. Center for Brain Tumor Therapy, University of Florida College of Medicine, McKnight Brain Institute, Gainesville, FL 32610, USA; Department of Neurosurgery, University of Florida College of Medicine, McKnight Brain Institute, Gainesville, FL 32610, USA
| | - Matthew R Sarkisian
- Department of Neuroscience, University of Florida College of Medicine, McKnight Brain Institute, Gainesville, FL 32610, USA; Preston A. Wells, Jr. Center for Brain Tumor Therapy, University of Florida College of Medicine, McKnight Brain Institute, Gainesville, FL 32610, USA.
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30
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Prodosmo A, Buffone A, Mattioni M, Barnabei A, Persichetti A, De Leo A, Appetecchia M, Nicolussi A, Coppa A, Sciacchitano S, Giordano C, Pinnarò P, Sanguineti G, Strigari L, Alessandrini G, Facciolo F, Cosimelli M, Grazi GL, Corrado G, Vizza E, Giannini G, Soddu S. Detection of ATM germline variants by the p53 mitotic centrosomal localization test in BRCA1/2-negative patients with early-onset breast cancer. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2016; 35:135. [PMID: 27599564 PMCID: PMC5012020 DOI: 10.1186/s13046-016-0410-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 08/23/2016] [Indexed: 12/20/2022]
Abstract
BACKGROUND Variant ATM heterozygotes have an increased risk of developing cancer, cardiovascular diseases, and diabetes. Costs and time of sequencing and ATM variant complexity make large-scale, general population screenings not cost-effective yet. Recently, we developed a straightforward, rapid, and inexpensive test based on p53 mitotic centrosomal localization (p53-MCL) in peripheral blood mononuclear cells (PBMCs) that diagnoses mutant ATM zygosity and recognizes tumor-associated ATM polymorphisms. METHODS Fresh PBMCs from 496 cancer patients were analyzed by p53-MCL: 90 cases with familial BRCA1/2-positive and -negative breast and/or ovarian cancer, 337 with sporadic cancers (ovarian, lung, colon, and post-menopausal breast cancers), and 69 with breast/thyroid cancer. Variants were confirmed by ATM sequencing. RESULTS A total of seven individuals with ATM variants were identified, 5/65 (7.7 %) in breast cancer cases of familial breast and/or ovarian cancer and 2/69 (2.9 %) in breast/thyroid cancer. No variant ATM carriers were found among the other cancer cases. Excluding a single case in which both BRCA1 and ATM were mutated, no p53-MCL alterations were observed in BRCA1/2-positive cases. CONCLUSIONS These data validate p53-MCL as reliable and specific test for germline ATM variants, confirm ATM as breast cancer susceptibility gene, and highlight a possible association with breast/thyroid cancers.
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Affiliation(s)
- Andrea Prodosmo
- Unit of Cellular Networks and Molecular Therapeutic Targets, Department of Research, Advanced Diagnostic, and Technological Innovation, Regina Elena National Cancer Institute - IRCCS, Via Elio Chianesi 53, 00144, Rome, Italy
| | - Amelia Buffone
- Department of Molecular Medicine, University La Sapienza, Rome, Italy
| | - Manlio Mattioni
- Unit of Cellular Networks and Molecular Therapeutic Targets, Department of Research, Advanced Diagnostic, and Technological Innovation, Regina Elena National Cancer Institute - IRCCS, Via Elio Chianesi 53, 00144, Rome, Italy
| | - Agnese Barnabei
- Endocrinology Unit, Department of Clinical and Experimental Oncology, Regina Elena National Cancer Institute - IRCCS, Rome, Italy
| | - Agnese Persichetti
- Endocrinology Unit, Department of Clinical and Experimental Oncology, Regina Elena National Cancer Institute - IRCCS, Rome, Italy.,Department of Molecular Medicine, University La Sapienza, Rome, Italy
| | - Aurora De Leo
- Endocrinology Unit, Department of Clinical and Experimental Oncology, Regina Elena National Cancer Institute - IRCCS, Rome, Italy
| | - Marialuisa Appetecchia
- Endocrinology Unit, Department of Clinical and Experimental Oncology, Regina Elena National Cancer Institute - IRCCS, Rome, Italy
| | - Arianna Nicolussi
- Department of Experimental Medicine, Sapienza University of Rome, Policlinico Umberto I, Viale Regina Elena, 32400161, Rome, Italy
| | - Anna Coppa
- Department of Experimental Medicine, Sapienza University of Rome, Policlinico Umberto I, Viale Regina Elena, 32400161, Rome, Italy
| | - Salvatore Sciacchitano
- Department of Clinical and Molecular Medicine, University La Sapienza, Laboratorio di Ricerca Biomedica, Fondazione Università Niccolò Cusano per la Ricerca Medico Scientifica, Rome, Italy
| | - Carolina Giordano
- Radiotherapy Unit, Department of Research, Advanced Diagnostic, and Technological Innovation, Regina Elena National Cancer Institute - IRCCS, Rome, Italy
| | - Paola Pinnarò
- Radiotherapy Unit, Department of Research, Advanced Diagnostic, and Technological Innovation, Regina Elena National Cancer Institute - IRCCS, Rome, Italy
| | - Giuseppe Sanguineti
- Radiotherapy Unit, Department of Research, Advanced Diagnostic, and Technological Innovation, Regina Elena National Cancer Institute - IRCCS, Rome, Italy
| | - Lidia Strigari
- Medical Physics Unit, Department of Research, Advanced Diagnostic, and Technological Innovation, Regina Elena National Cancer Institute - IRCCS, Rome, Italy
| | - Gabriele Alessandrini
- Toracic Surgery Unit, Department of Clinical and Experimental Oncology, Regina Elena National Cancer Institute - IRCCS, Rome, Italy
| | - Francesco Facciolo
- Toracic Surgery Unit, Department of Clinical and Experimental Oncology, Regina Elena National Cancer Institute - IRCCS, Rome, Italy
| | - Maurizio Cosimelli
- Hepato-pancreato-biliary Surgery Unit, Department of Clinical and Experimental Oncology, Regina Elena National Cancer Institute - IRCCS, Rome, Italy
| | - Gian Luca Grazi
- Hepato-pancreato-biliary Surgery Unit, Department of Clinical and Experimental Oncology, Regina Elena National Cancer Institute - IRCCS, Rome, Italy
| | - Giacomo Corrado
- Gynecological Oncology Unit, Department of Clinical and Experimental Oncology, Regina Elena National Cancer Institute - IRCCS, Rome, Italy
| | - Enrico Vizza
- Gynecological Oncology Unit, Department of Clinical and Experimental Oncology, Regina Elena National Cancer Institute - IRCCS, Rome, Italy
| | - Giuseppe Giannini
- Istituto Pasteur-Fondazione Cenci Bolognetti, Department of Molecular Medicine, University La Sapienza, Rome, Italy. .,Department of Molecular Medicine, University La Sapienza, Rome, Italy.
| | - Silvia Soddu
- Unit of Cellular Networks and Molecular Therapeutic Targets, Department of Research, Advanced Diagnostic, and Technological Innovation, Regina Elena National Cancer Institute - IRCCS, Via Elio Chianesi 53, 00144, Rome, Italy.
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Abstract
ATR (Ataxia Telangiectasia and Rad3-related) is a member of the Phosphatidylinositol 3-kinase-related kinases (PIKKs) family, amongst six other vertebrate proteins known so far. ATR is indispensable for cell survival and its essential role is in sensing DNA damage and initiating appropriate repair responses. In this review we highlight emerging and recent observations connecting ATR to alternative roles in controlling the nuclear envelope, nucleolus, centrosome and other organelles in response to both internal and external stress conditions. We propose that ATR functions control cell plasticity by sensing structural deformations of different cellular components, including DNA and initiating appropriate repair responses, most of which are yet to be understood completely.
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Affiliation(s)
- Gururaj Rao Kidiyoor
- Istituto FIRC di Oncologia Molecolare, Milan, Italy; University of Milan, Milan, Italy
| | - Amit Kumar
- Developmental Toxicology Laboratory, Systems Toxicology and Health Risk Assessment Group, CSIR-Indian Institute of Toxicology Research, M.G. Marg, Lucknow 226001, India; Academy of Scientific and Innovative Research (AcSIR), India
| | - Marco Foiani
- Istituto FIRC di Oncologia Molecolare, Milan, Italy; University of Milan, Milan, Italy.
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32
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Abstract
PURPOSE OF REVIEW In the past decade a wealth of publications have established the central role of cilia and centrosomes in the pathogenesis of cystic kidney diseases, associated or not with extrarenal symptoms. This review outlines recent findings that have unexpectedly linked ciliary and centrosomal proteins to DNA damage and repair and have opened new perspectives for the comprehension of the pathogenesis of these diseases. RECENT FINDINGS Several ciliopathy proteins that contribute to the pathogenesis of cystic kidney diseases and ciliopathy-related phenotypes have been recently reported to participate in the elaborated pathways that control DNA replication and repair, suggesting that malfunction of these biological processes may be a common denominator of some ciliopathy-related diseases. SUMMARY In this review, the author briefly describes the established connections existing between cilia, centrosome, and cell cycle and provides basic information about DNA damage and repair. The author then examines more closely the single ciliopathy genes that have been associated with DNA repair pathways and their known biological functions.
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33
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Oakley BR, Paolillo V, Zheng Y. γ-Tubulin complexes in microtubule nucleation and beyond. Mol Biol Cell 2015; 26:2957-62. [PMID: 26316498 PMCID: PMC4551311 DOI: 10.1091/mbc.e14-11-1514] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Revised: 07/02/2015] [Accepted: 07/02/2015] [Indexed: 01/07/2023] Open
Abstract
Tremendous progress has been made in understanding the functions of γ-tubulin and, in particular, its role in microtubule nucleation since the publication of its discovery in 1989. The structure of γ-tubulin has been determined, and the components of γ-tubulin complexes have been identified. Significant progress in understanding the structure of the γ-tubulin ring complex and its components has led to a persuasive model for how these complexes nucleate microtubule assembly. At the same time, data have accumulated that γ-tubulin has important but less well understood functions that are not simply a consequence of its function in microtubule nucleation. These include roles in the regulation of plus-end microtubule dynamics, gene regulation, and mitotic and cell cycle regulation. Finally, evidence is emerging that γ-tubulin mutations or alterations of γ-tubulin expression play an important role in certain types of cancer and in other diseases.
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Affiliation(s)
- Berl R Oakley
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045
| | - Vitoria Paolillo
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045
| | - Yixian Zheng
- Department of Embryology, Carnegie Institution for Science, Baltimore, MD 21218
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Zhao B, Zhang WD, Duan YL, Lu YQ, Cun YX, Li CH, Guo K, Nie WH, Li L, Zhang R, Zheng P. Filia Is an ESC-Specific Regulator of DNA Damage Response and Safeguards Genomic Stability. Cell Stem Cell 2015; 16:684-98. [PMID: 25936915 DOI: 10.1016/j.stem.2015.03.017] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Revised: 02/16/2015] [Accepted: 03/22/2015] [Indexed: 12/20/2022]
Abstract
Pluripotent stem cells (PSCs) hold great promise in cell-based therapy, but the genomic instability seen in culture hampers their full application. A greater understanding of the factors that regulate genomic stability in PSCs could help address this issue. Here we describe the identification of Filia as a specific regulator of genomic stability in mouse embryonic stem cells (ESCs). Filia expression is induced by genotoxic stress. Filia promotes centrosome integrity and regulates the DNA damage response (DDR) through multiple pathways, including DDR signaling, cell-cycle checkpoints and damage repair, ESC differentiation, and apoptosis. Filia depletion causes ESC genomic instability, induces resistance to apoptosis, and promotes malignant transformation. As part of its role in DDR, Filia interacts with PARP1 and stimulates its enzymatic activity. Filia also constitutively resides on centrosomes and translocates to DNA damage sites and mitochondria, consistent with its multifaceted roles in regulating centrosome integrity, damage repair, and apoptosis.
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Affiliation(s)
- Bo Zhao
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China; Yunnan Key Laboratory of Animal Reproduction, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China
| | - Wei-Dao Zhang
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China; Yunnan Key Laboratory of Animal Reproduction, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China; Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming 650204, China
| | - Ying-Liang Duan
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China; Yunnan Key Laboratory of Animal Reproduction, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China
| | - Yong-Qing Lu
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China; Yunnan Key Laboratory of Animal Reproduction, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China
| | - Yi-Xian Cun
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China; Yunnan Key Laboratory of Animal Reproduction, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China
| | - Chao-Hui Li
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China; Yunnan Key Laboratory of Animal Reproduction, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China; Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming 650204, China
| | - Kun Guo
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China; Yunnan Key Laboratory of Animal Reproduction, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China; Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming 650204, China
| | - Wen-Hui Nie
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China
| | - Lei Li
- State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Rugang Zhang
- Gene Expression and Regulation Program, The Wistar Institute Cancer Center, The Wistar Institute, Philadelphia, PA 19104, USA
| | - Ping Zheng
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China; Yunnan Key Laboratory of Animal Reproduction, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China.
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35
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Iezzi S, Fanciulli M. Discovering Che-1/AATF: a new attractive target for cancer therapy. Front Genet 2015; 6:141. [PMID: 25914721 PMCID: PMC4392318 DOI: 10.3389/fgene.2015.00141] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Accepted: 03/24/2015] [Indexed: 12/12/2022] Open
Abstract
The transcriptional cofactor Che-1/AATF is currently emerging as an important component of the DNA damage response (DDR) machinery, the complex signaling network that maintains genome integrity and prevents tumorigenesis. Moreover this protein is involved in a wide range of cellular pathways, regulating proliferation and survival in both physiological and pathological conditions. Notably, some evidence indicates that dysregulation of Che-1/AATF levels are associated with the transformation process and elevated levels of Che-1/AATF are required for tumor cell survival. It is for these reasons that Che-1/AATF has been regarded as an attractive, still theoretical, therapeutic target for cancer treatments. In this review, we will provide an updated overview of Che-1/AATF activities, from transcriptional regulation to DDR.
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Affiliation(s)
- Simona Iezzi
- Laboratory of Epigenetics, Molecular Medicine Area, Regina Elena National Cancer Institute, Rome Italy
| | - Maurizio Fanciulli
- Laboratory of Epigenetics, Molecular Medicine Area, Regina Elena National Cancer Institute, Rome Italy
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Rodgers W, Byrum JN, Sapkota H, Rahman NS, Cail RC, Zhao S, Schatz DG, Rodgers KK. Spatio-temporal regulation of RAG2 following genotoxic stress. DNA Repair (Amst) 2015; 27:19-27. [PMID: 25625798 PMCID: PMC4336829 DOI: 10.1016/j.dnarep.2014.12.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Revised: 12/23/2014] [Accepted: 12/31/2014] [Indexed: 11/30/2022]
Abstract
V(D)J recombination of lymphocyte antigen receptor genes occurs via the formation of DNA double strand breaks (DSBs) through the activity of RAG1 and RAG2. The co-existence of RAG-independent DNA DSBs generated by genotoxic stressors potentially increases the risk of incorrect repair and chromosomal abnormalities. However, it is not known whether cellular responses to DSBs by genotoxic stressors affect the RAG complex. Using cellular imaging and subcellular fractionation approaches, we show that formation of DSBs by treating cells with DNA damaging agents causes export of nuclear RAG2. Within the cytoplasm, RAG2 exhibited substantial enrichment at the centrosome. Further, RAG2 export was sensitive to inhibition of ATM, and was reversed following DNA repair. The core region of RAG2 was sufficient for export, but not centrosome targeting, and RAG2 export was blocked by mutation of Thr(490). In summary, DNA damage triggers relocalization of RAG2 from the nucleus to centrosomes, suggesting a novel mechanism for modulating cellular responses to DSBs in developing lymphocytes.
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Affiliation(s)
- William Rodgers
- Department of Biochemistry and Molecular Biology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Department of Microbiology and Immunology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Department of Pathology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Jennifer N Byrum
- Department of Biochemistry and Molecular Biology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Hem Sapkota
- Department of Biochemistry and Molecular Biology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Negar S Rahman
- Department of Biochemistry and Molecular Biology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Robert C Cail
- Department of Biochemistry and Molecular Biology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Shuying Zhao
- Department of Biochemistry and Molecular Biology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - David G Schatz
- Department of Immunobiology and Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, CT, USA
| | - Karla K Rodgers
- Department of Biochemistry and Molecular Biology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
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Kumar A, Mazzanti M, Mistrik M, Kosar M, Beznoussenko GV, Mironov AA, Garrè M, Parazzoli D, Shivashankar GV, Scita G, Bartek J, Foiani M. ATR mediates a checkpoint at the nuclear envelope in response to mechanical stress. Cell 2015; 158:633-46. [PMID: 25083873 PMCID: PMC4121522 DOI: 10.1016/j.cell.2014.05.046] [Citation(s) in RCA: 155] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2013] [Revised: 04/14/2014] [Accepted: 05/28/2014] [Indexed: 11/16/2022]
Abstract
ATR controls chromosome integrity and chromatin dynamics. We have previously shown that yeast Mec1/ATR promotes chromatin detachment from the nuclear envelope to counteract aberrant topological transitions during DNA replication. Here, we provide evidence that ATR activity at the nuclear envelope responds to mechanical stress. Human ATR associates with the nuclear envelope during S phase and prophase, and both osmotic stress and mechanical stretching relocalize ATR to nuclear membranes throughout the cell cycle. The ATR-mediated mechanical response occurs within the range of physiological forces, is reversible, and is independent of DNA damage signaling. ATR-defective cells exhibit aberrant chromatin condensation and nuclear envelope breakdown. We propose that mechanical forces derived from chromosome dynamics and torsional stress on nuclear membranes activate ATR to modulate nuclear envelope plasticity and chromatin association to the nuclear envelope, thus enabling cells to cope with the mechanical strain imposed by these molecular processes. ATR localizes at the nuclear envelope in S phase and prophase ATR responds to mechanical stress by relocalizing to the nuclear envelope The ATR mechanical response is fast and reversible ATR coordinates chromatin condensation and nuclear envelope breakdown
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Affiliation(s)
- Amit Kumar
- Fondazione Istituto FIRC di Oncologia Molecolare (IFOM), Via Adamello 16, 20139 Milan, Italy
| | | | - Martin Mistrik
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, 77115 Olomouc, Czech Republic
| | - Martin Kosar
- Danish Cancer Society Research Center, 2100 Copenhagen, Denmark; Institute of Molecular Genetics, v.v.i., Academy of Sciences of the Czech Republic, 14220 Prague, Czech Republic
| | - Galina V Beznoussenko
- Fondazione Istituto FIRC di Oncologia Molecolare (IFOM), Via Adamello 16, 20139 Milan, Italy
| | - Alexandre A Mironov
- Fondazione Istituto FIRC di Oncologia Molecolare (IFOM), Via Adamello 16, 20139 Milan, Italy
| | - Massimiliano Garrè
- Fondazione Istituto FIRC di Oncologia Molecolare (IFOM), Via Adamello 16, 20139 Milan, Italy
| | - Dario Parazzoli
- Fondazione Istituto FIRC di Oncologia Molecolare (IFOM), Via Adamello 16, 20139 Milan, Italy
| | - G V Shivashankar
- Mechanobiology Institute and Department of Biological Sciences, National University of Singapore, 117411 Singapore, Singapore
| | - Giorgio Scita
- Fondazione Istituto FIRC di Oncologia Molecolare (IFOM), Via Adamello 16, 20139 Milan, Italy; Università degli Studi di Milano, 20122 Milan, Italy
| | - Jiri Bartek
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, 77115 Olomouc, Czech Republic; Danish Cancer Society Research Center, 2100 Copenhagen, Denmark; Institute of Molecular Genetics, v.v.i., Academy of Sciences of the Czech Republic, 14220 Prague, Czech Republic.
| | - Marco Foiani
- Fondazione Istituto FIRC di Oncologia Molecolare (IFOM), Via Adamello 16, 20139 Milan, Italy; Università degli Studi di Milano, 20122 Milan, Italy.
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Zannini L, Delia D, Buscemi G. CHK2 kinase in the DNA damage response and beyond. J Mol Cell Biol 2014; 6:442-57. [PMID: 25404613 PMCID: PMC4296918 DOI: 10.1093/jmcb/mju045] [Citation(s) in RCA: 287] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Revised: 09/17/2014] [Accepted: 09/24/2014] [Indexed: 12/21/2022] Open
Abstract
The serine/threonine kinase CHK2 is a key component of the DNA damage response. In human cells, following genotoxic stress, CHK2 is activated and phosphorylates >20 proteins to induce the appropriate cellular response, which, depending on the extent of damage, the cell type, and other factors, could be cell cycle checkpoint activation, induction of apoptosis or senescence, DNA repair, or tolerance of the damage. Recently, CHK2 has also been found to have cellular functions independent of the presence of nuclear DNA lesions. In particular, CHK2 participates in several molecular processes involved in DNA structure modification and cell cycle progression. In this review, we discuss the activity of CHK2 in response to DNA damage and in the maintenance of the biological functions in unstressed cells. These activities are also considered in relation to a possible role of CHK2 in tumorigenesis and, as a consequence, as a target of cancer therapy.
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Affiliation(s)
- Laura Zannini
- Department of Experimental Oncology, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Amadeo 42, 20133 Milan, Italy
| | - Domenico Delia
- Department of Experimental Oncology, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Amadeo 42, 20133 Milan, Italy
| | - Giacomo Buscemi
- Department of Biosciences, University of Milan, via Celoria 26, 20133 Milan, Italy
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Gustafsson AS, Abramenkovs A, Stenerlöw B. Suppression of DNA-dependent protein kinase sensitize cells to radiation without affecting DSB repair. Mutat Res 2014; 769:1-10. [PMID: 25771720 DOI: 10.1016/j.mrfmmm.2014.06.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Revised: 06/04/2014] [Accepted: 06/16/2014] [Indexed: 06/04/2023]
Abstract
Efficient and correct repair of DNA double-strand break (DSB) is critical for cell survival. Defects in the DNA repair may lead to cell death, genomic instability and development of cancer. The catalytic subunit of DNA-dependent protein kinase (DNA-PKcs) is an essential component of the non-homologous end joining (NHEJ) which is the major DSB repair pathway in mammalian cells. In the present study, by using siRNA against DNA-PKcs in four human cell lines, we examined how low levels of DNA-PKcs affected cellular response to ionizing radiation. Decrease of DNA-PKcs levels by 80-95%, induced by siRNA treatment, lead to extreme radiosensitivity, similar to that seen in cells completely lacking DNA-PKcs and low levels of DNA-PKcs promoted cell accumulation in G2/M phase after irradiation and blocked progression of mitosis. Surprisingly, low levels of DNA-PKcs did not affect the repair capacity and the removal of 53BP1 or γ-H2AX foci and rejoining of DSB appeared normal. This was in strong contrast to cells completely lacking DNA-PKcs and cells treated with the DNA-PKcs inhibitor NU7441, in which DSB repair were severely compromised. This suggests that there are different mechanisms by which loss of DNA-PKcs functions can sensitize cells to ionizing radiation. Further, foci of phosphorylated DNA-PKcs (T2609 and S2056) co-localized with DSB and this was independent of the amount of DNA-PKcs but foci of DNA-PKcs was only seen in siRNA-treated cells. Our study emphasizes on the critical role of DNA-PKcs for maintaining survival after radiation exposure which is uncoupled from its essential function in DSB repair. This could have implications for the development of therapeutic strategies aiming to radiosensitize tumors by affecting the DNA-PKcs function.
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Affiliation(s)
- Ann-Sofie Gustafsson
- Section of Biomedical Radiation Sciences, Department of Radiology, Oncology and Radiation Science, Rudbeck Laboratory, Uppsala University, Dag Hammarskjölds Väg 20, SE-751 85 Uppsala, Sweden.
| | - Andris Abramenkovs
- Section of Biomedical Radiation Sciences, Department of Radiology, Oncology and Radiation Science, Rudbeck Laboratory, Uppsala University, Dag Hammarskjölds Väg 20, SE-751 85 Uppsala, Sweden
| | - Bo Stenerlöw
- Section of Biomedical Radiation Sciences, Department of Radiology, Oncology and Radiation Science, Rudbeck Laboratory, Uppsala University, Dag Hammarskjölds Väg 20, SE-751 85 Uppsala, Sweden
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Mirzaa GM, Vitre B, Carpenter G, Abramowicz I, Gleeson JG, Paciorkowski AR, Cleveland DW, Dobyns WB, O’Driscoll M. Mutations in CENPE define a novel kinetochore-centromeric mechanism for microcephalic primordial dwarfism. Hum Genet 2014; 133:1023-39. [PMID: 24748105 PMCID: PMC4415612 DOI: 10.1007/s00439-014-1443-3] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Accepted: 03/31/2014] [Indexed: 11/30/2022]
Abstract
Defects in centrosome, centrosomal-associated and spindle-associated proteins are the most frequent cause of primary microcephaly (PM) and microcephalic primordial dwarfism (MPD) syndromes in humans. Mitotic progression and segregation defects, microtubule spindle abnormalities and impaired DNA damage-induced G2-M cell cycle checkpoint proficiency have been documented in cell lines from these patients. This suggests that impaired mitotic entry, progression and exit strongly contribute to PM and MPD. Considering the vast protein networks involved in coordinating this cell cycle stage, the list of potential target genes that could underlie novel developmental disorders is large. One such complex network, with a direct microtubule-mediated physical connection to the centrosome, is the kinetochore. This centromeric-associated structure nucleates microtubule attachments onto mitotic chromosomes. Here, we described novel compound heterozygous variants in CENPE in two siblings who exhibit a profound MPD associated with developmental delay, simplified gyri and other isolated abnormalities. CENPE encodes centromere-associated protein E (CENP-E), a core kinetochore component functioning to mediate chromosome congression initially of misaligned chromosomes and in subsequent spindle microtubule capture during mitosis. Firstly, we present a comprehensive clinical description of these patients. Then, using patient cells we document abnormalities in spindle microtubule organization, mitotic progression and segregation, before modeling the cellular pathogenicity of these variants in an independent cell system. Our cellular analysis shows that a pathogenic defect in CENP-E, a kinetochore-core protein, largely phenocopies PCNT-mutated microcephalic osteodysplastic primordial dwarfism-type II patient cells. PCNT encodes a centrosome-associated protein. These results highlight a common underlying pathomechanism. Our findings provide the first evidence for a kinetochore-based route to MPD in humans.
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Affiliation(s)
- Ghayda M. Mirzaa
- Division of Genetic Medicine, Department of Pediatrics, University of Washington and Center for Integrative Brain Research, Seattle Children’s Research Institute, Seattle, WA, USA
| | - Benjamin Vitre
- Ludwig Institute for Cancer Research, Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Gillian Carpenter
- Human DNA Damage Response Disorders Group, Genome Damage & Stability Centre, University of Sussex, Falmer, Brighton, BN1 9RQ, United Kingdom
| | - Iga Abramowicz
- Human DNA Damage Response Disorders Group, Genome Damage & Stability Centre, University of Sussex, Falmer, Brighton, BN1 9RQ, United Kingdom
| | - Joseph G. Gleeson
- Department of Neurosciences and Pediatrics, University of California, San Diego, La Jolla, CA, USA
| | - Alex R. Paciorkowski
- Departments of Neurology, Pediatrics & Biomedical Genetics, Center for Neural Development & Disease, University of Rochester Medical Center, Rochester, NY, USA
| | - Don W. Cleveland
- Ludwig Institute for Cancer Research, Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA, USA
| | - William B. Dobyns
- Division of Genetic Medicine, Department of Pediatrics, University of Washington and Center for Integrative Brain Research, Seattle Children’s Research Institute, Seattle, WA, USA
| | - Mark O’Driscoll
- Human DNA Damage Response Disorders Group, Genome Damage & Stability Centre, University of Sussex, Falmer, Brighton, BN1 9RQ, United Kingdom
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RNF144A, an E3 ubiquitin ligase for DNA-PKcs, promotes apoptosis during DNA damage. Proc Natl Acad Sci U S A 2014; 111:E2646-55. [PMID: 24979766 DOI: 10.1073/pnas.1323107111] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Several ring between ring fingers (RBR) -domain proteins, such as Parkin and Parc, have been shown to be E3 ligases involved in important biological processes. Here, we identify a poorly characterized RBR protein, Ring Finger protein 144A (RNF144A), as the first, to our knowledge, mammalian E3 ubiquitin ligase for DNA-PKcs. We show that DNA damage induces RNF144A expression in a p53-dependent manner. RNF144A is mainly localized in the cytoplasmic vesicles and plasma membrane and interacts with cytoplasmic DNA-dependent protein kinase, catalytic subunit (DNA-PKcs). DNA-PKcs plays a critical role in the nonhomologous end-joining DNA repair pathway and provides prosurvival signaling during DNA damage. We show that RNF144A induces ubiquitination of DNA-PKcs in vitro and in vivo and promotes its degradation. Depletion of RNF144A leads to an increased level of DNA-PKcs and resistance to DNA damaging agents, which is reversed by a DNA-PK inhibitor. Taken together, our data suggest that RNF144A may be involved in p53-mediated apoptosis through down-regulation of DNA-PKcs when cells suffer from persistent or severe DNA damage insults.
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Huang B, Shang ZF, Li B, Wang Y, Liu XD, Zhang SM, Guan H, Rang WQ, Hu JA, Zhou PK. DNA-PKcs associates with PLK1 and is involved in proper chromosome segregation and cytokinesis. J Cell Biochem 2014; 115:1077-88. [PMID: 24166892 DOI: 10.1002/jcb.24703] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Accepted: 10/21/2013] [Indexed: 12/12/2022]
Abstract
Accurate mitotic regulation is as important as intrinsic DNA repair for maintaining genomic stability. It is believed that these two cellular mechanisms are interconnected with DNA damage. DNA-PKcs is a critical component of the non-homologous end-joining pathway of DNA double-stranded break repair, and it was recently discovered to be involved in mitotic processing. However, the underlying mechanism of DNA-PKcs action in mitotic control is unknown. Here, we demonstrated that depletion of DNA-PKcs led to the dysregulation of mitotic progression in response to DNA damage, which eventually resulted in multiple failures, including failure to segregate sister chromatids and failure to complete cytokinesis, with daughter cells becoming fused again. The depletion of DNA-PKcs resulted in a notable failure of cytokinesis, with a high incidence of multinucleated cells. There were also cytoplasmic bridges containing DNA that continuously connected the daughter cells after DNA damage was induced. Phosphorylated DNA-PKcs (T2609) colocalizes with PLK1 throughout mitosis, including at the centrosomes from prophase to anaphase and at the kinetochores from prometaphase to metaphase, with accumulation at the midbody during cytokinesis. Importantly, DNA-PKcs was found to associate with PLK1 in the mitotic phase, and the depletion of DNA-PKcs resulted in the overexpression of PLK1 due to increased protein stability. However, deficiency in DNA-PKcs attenuated the recruitment of phosphorylated PLK1 to the midbody but not to the kinetochores and centrosomes. Our results demonstrate the functional association of DNA-PKcs with PLK1, especially in chromosomal segregation and cytokinesis control.
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Affiliation(s)
- Bo Huang
- School of Public Heath, Central South University, Changsha, Hunan Province, 410078, P.R. China; Department of Radiation Toxicology and Oncology, Beijing Institute of Radiation Medicine, Beijing, 100850, P.R. China; Institute for Environmental Medicine and Radiation Hygiene, The College of Public Health, University of South China, Hengyang, Hunan Province, 421000, P.R. China
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diIorio P, Rittenhouse AR, Bortell R, Jurczyk A. Role of cilia in normal pancreas function and in diseased states. ACTA ACUST UNITED AC 2014; 102:126-38. [PMID: 24861006 DOI: 10.1002/bdrc.21064] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/14/2014] [Indexed: 12/25/2022]
Abstract
Primary cilia play an essential role in modulating signaling cascades that shape cellular responses to environmental cues to maintain proper tissue development. Mutations in primary cilium proteins have been linked to several rare developmental disorders, collectively known as ciliopathies. Together with other disorders associated with dysfunctional cilia/centrosomes, affected individuals have increased risk of developing metabolic syndrome, neurologic disorders, and diabetes. In pancreatic tissues, cilia are found exclusively in islet and ductal cells where they play an essential role in pancreatic tissue organization. Their absence or disorganization leads to pancreatic duct abnormalities, acinar cell loss, polarity defects, and dysregulated insulin secretion. Cilia in pancreatic tissues are hubs for cellular signaling. Many signaling components, such as Hh, Notch, and Wnt, localize to pancreatic primary cilia and are necessary for proper development of pancreatic epithelium and β-cell morphogenesis. Receptors for neuroendocrine hormones, such as Somatostatin Receptor 3, also localize to the cilium and may play a more direct role in controlling insulin secretion due to somatostatin's inhibitory function. Finally, unique calcium signaling, which is at the heart of β-cell function, also occurs in primary cilia. Whereas voltage-gated calcium channels trigger insulin secretion and serve a variety of homeostatic functions in β-cells, transient receptor potential channels regulate calcium levels within the cilium that may serve as a feedback mechanism, regulating insulin secretion. This review article summarizes our current understanding of the role of primary cilia in normal pancreas function and in the diseased state.
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Affiliation(s)
- Philip diIorio
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts
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Eliezer Y, Argaman L, Kornowski M, Roniger M, Goldberg M. Interplay between the DNA damage proteins MDC1 and ATM in the regulation of the spindle assembly checkpoint. J Biol Chem 2014; 289:8182-93. [PMID: 24509855 DOI: 10.1074/jbc.m113.532739] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
To avoid genomic instability, cells have developed surveillance mechanisms such as the spindle assembly checkpoint (SAC) and the DNA damage response. ATM and MDC1 are central players of the cellular response to DNA double-strand breaks. Here, we identify a new role for these proteins in the regulation of mitotic progression and in SAC activation. MDC1 localizes at mitotic kinetochores following SAC activation in an ATM-dependent manner. ATM phosphorylates histone H2AX at mitotic kinetochores, and this phosphorylation is required for MDC1 localization at kinetochores. ATM and MDC1 are needed for kinetochore localization of the inhibitory mitotic checkpoint complex components, Mad2 and Cdc20, and for the maintenance of the mitotic checkpoint complex integrity. This probably relies on the interaction of MDC1 with the MCC. In this work, we have established that ATM and MDC1 maintain genomic stability not only by controlling the DNA damage response, but also by regulating SAC activation, providing an important link between these two essential biological processes.
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Affiliation(s)
- Yifat Eliezer
- From the Department of Genetics, The Institute of Life Sciences, The Hebrew University, Jerusalem 91904, Israel
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45
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Lai WL, Hung WY, Ching YP. The tumor suppressor, TAX1BP2, is a novel substrate of ATM kinase. Oncogene 2013; 33:5303-9. [PMID: 24240686 DOI: 10.1038/onc.2013.481] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Revised: 10/04/2013] [Accepted: 10/08/2013] [Indexed: 12/27/2022]
Abstract
DNA damage repair response is a crucial process for cancer prevention. One of the key regulators of this process is ataxia telangiectasia mutated (ATM) kinase, which modulates the p53 level by direct and indirect phosphorylation. Recent data showed that ATM also localizes at the centrosome, but the function remains elusive. TAX1BP2 was initially identified as a novel centrosomal protein that interacts directly with the human T-cell leukemia virus type 1 (HTLV-1)-encoded oncoprotein, Tax, and inhibits centrosome overduplication. Subsequently, TAX1BP2 was found to be a tumor suppressor in hepatocellular carcinoma, and accumulation of TAX1BP2 was observed upon chemotherapeutic drug treatment. Here, we provide evidence that TAX1BP2 is a direct phosphorylation substrate of ATM. The protein level of TAX1BP2 is significantly upregulated in response to DNA damaging agents. Serine-922 of TAX1BP2 is the phosphorylation site of ATM, and such phosphorylation modulates the protein stability, ubiquitination and tumor suppressor activity of TAX1BP2. Taken together, we demonstrate for the first time that TAX1BP2 is a novel effector of ATM in DNA damage response and delineated a new mechanism by which ATM stabilizes the tumor suppressor TAX1BP2.
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Affiliation(s)
- W L Lai
- Department of Anatomy, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - W Y Hung
- Department of Anatomy, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Y P Ching
- 1] Department of Anatomy, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China [2] State Key Laboratory for Liver Research, The University of Hong Kong, Hong Kong, China [3] State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, China
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Zou J, Tian F, Li J, Pickner W, Long M, Rezvani K, Wang H, Zhang D. FancJ regulates interstrand crosslinker induced centrosome amplification through the activation of polo-like kinase 1. Biol Open 2013; 2:1022-31. [PMID: 24167712 PMCID: PMC3798185 DOI: 10.1242/bio.20135801] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Accepted: 07/03/2013] [Indexed: 01/05/2023] Open
Abstract
DNA damage response (DDR) and the centrosome cycle are two of the most critical processes for maintaining a stable genome in animals. Sporadic evidence suggests a connection between these two processes. Here, we report our findings that six Fanconi Anemia (FA) proteins, including FancI and FancJ, localize to the centrosome. Intriguingly, we found that the localization of FancJ to the mother centrosome is stimulated by a DNA interstrand crosslinker, Mitomycin C (MMC). We further show that, in addition to its role in interstrand crosslinking (ICL) repair, FancJ also regulates the normal centrosome cycle as well as ICL induced centrosome amplification by activating the polo-like kinase 1 (PLK1). We have uncovered a novel function of FancJ in centrosome biogenesis and established centrosome amplification as an integral part of the ICL response.
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Affiliation(s)
- Jianqiu Zou
- Basic Biomedical Science Division, Sanford School of Medicine, University of South Dakota , Vermillion, South Dakota, 57069 , USA
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Sorino C, Bruno T, Desantis A, Di Certo MG, Iezzi S, De Nicola F, Catena V, Floridi A, Chessa L, Passananti C, Cundari E, Fanciulli M. Centrosomal Che-1 protein is involved in the regulation of mitosis and DNA damage response by mediating pericentrin (PCNT)-dependent Chk1 protein localization. J Biol Chem 2013; 288:23348-57. [PMID: 23798705 DOI: 10.1074/jbc.m113.465302] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
To combat threats posed by DNA damage, cells have evolved mechanisms, collectively termed DNA damage response (DDR). These mechanisms detect DNA lesions, signal their presence, and promote their repair. Centrosomes integrate G2/M checkpoint control and repair signals in response to genotoxic stress, acting as an efficient control mechanism when G2/M checkpoint function fails and mitosis begins in the presence of damaged DNA. Che-1 is an RNA polymerase II-binding protein involved in the regulation of gene transcription, induction of cell proliferation, and DDR. Here we provide evidence that in addition to its nuclear localization, Che-1 localizes at interphase centrosomes, where it accumulates following DNA damage or spindle poisons. We show that Che-1 depletion generates supernumerary centrosomes, multinucleated cells, and multipolar spindle formation. Notably, Che-1 depletion abolishes the ability of Chk1 to bind pericentrin and to localize at centrosomes, which, in its turn, deregulates the activation of centrosomal cyclin B-Cdk1 and advances entry into mitosis. Our results reinforce the notion that Che-1 plays an important role in DDR and that its contribution seems to be relevant for the spindle assembly checkpoint.
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Affiliation(s)
- Cristina Sorino
- Laboratory of Epigenetics, Molecular Medicine Area, Regina Elena Cancer Institute, Via E. Chianesi 53, 00144 Rome, Italy
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Kim S, Hwang SK, Lee M, Kwak H, Son K, Yang J, Kim SH, Lee CH. Fanconi anemia complementation group A (FANCA) localizes to centrosomes and functions in the maintenance of centrosome integrity. Int J Biochem Cell Biol 2013; 45:1953-61. [PMID: 23806870 DOI: 10.1016/j.biocel.2013.06.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Revised: 06/07/2013] [Accepted: 06/16/2013] [Indexed: 02/07/2023]
Abstract
Fanconi anemia (FA) proteins are known to play roles in the cellular response to DNA interstrand cross-linking lesions; however, several reports have suggested that FA proteins play additional roles. To elucidate novel functions of FA proteins, we used yeast two-hybrid screening to identify binding partners of the Fanconi anemia complementation group A (FANCA) protein. The candidate proteins included never-in-mitosis-gene A (NIMA)-related kinase 2 (Nek2), which functions in the maintenance of centrosome integrity. The interaction of FANCA and Nek2 was confirmed in human embryonic kidney (HEK) 293T cells. Furthermore, FANCA interacted with γ-tubulin and localized to centrosomes, most notably during the mitotic phase, confirming that FANCA is a centrosomal protein. Knockdown of FANCA increased the frequency of centrosomal abnormalities and enhanced the sensitivity of U2OS osteosarcoma cells to nocodazole, a microtubule-interfering agent. In vitro kinase assays indicated that Nek2 can phosphorylate FANCA at threonine-351 (T351), and analysis with a phospho-specific antibody confirmed that this phosphorylation occurred in response to nocodazole treatment. Furthermore, U2OS cells overexpressing the phosphorylation-defective T351A FANCA mutant showed numerical centrosomal abnormalities, aberrant mitotic arrest, and enhanced nocodazole sensitivity, implying that the Nek2-mediated T351 phosphorylation of FANCA is important for the maintenance of centrosomal integrity. Taken together, this study revealed that FANCA localizes to centrosomes and is required for the maintenance of centrosome integrity, possibly through its phosphorylation at T351 by Nek2.
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Affiliation(s)
- Sunshin Kim
- New Experimental Therapeutics Branch, Research Institute, National Cancer Center, 323 Ilsan-ro, Ilsandong-gu, Goyang, Gyeonggi 410-769, Republic of Korea
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Chouinard G, Clément I, Lafontaine J, Rodier F, Schmitt E. Cell cycle-dependent localization of CHK2 at centrosomes during mitosis. Cell Div 2013; 8:7. [PMID: 23680298 PMCID: PMC3668180 DOI: 10.1186/1747-1028-8-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Accepted: 05/09/2013] [Indexed: 01/26/2023] Open
Abstract
Background Centrosomes function primarily as microtubule-organizing centres and play a crucial role during mitosis by organizing the bipolar spindle. In addition to this function, centrosomes act as reaction centers where numerous key regulators meet to control cell cycle progression. One of these factors involved in genome stability, the checkpoint kinase CHK2, was shown to localize at centrosomes throughout the cell cycle. Results Here, we show that CHK2 only localizes to centrosomes during mitosis. Using wild-type and CHK2−/− HCT116 human colon cancer cells and human osteosarcoma U2OS cells depleted for CHK2 with small hairpin RNAs we show that several CHK2 antibodies are non-specific and cross-react with an unknown centrosomal protein(s) by immunofluorescence. To characterize the localization of CHK2, we generated cells expressing inducible GFP-CHK2 and Flag-CHK2 fusion proteins. We show that CHK2 localizes to the nucleus in interphase cells but that a fraction of CHK2 associates with the centrosomes in a Polo-like kinase 1-dependent manner during mitosis, from early mitotic stages until cytokinesis. Conclusion Our findings demonstrate that a subpopulation of CHK2 localizes at the centrosomes in mitotic cells but not in interphase. These results are consistent with previous reports supporting a role for CHK2 in the bipolar spindle formation and the timely progression of mitosis.
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Affiliation(s)
- Guillaume Chouinard
- Centre de recherche, Centre hospitalier de l'Université de Montréal (CRCHUM), Hôpital Notre-Dame et Institut du cancer de Montréal, Montréal, Québec, Canada.
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Leonard MK, Hill NT, Bubulya PA, Kadakia MP. The PTEN-Akt pathway impacts the integrity and composition of mitotic centrosomes. Cell Cycle 2013; 12:1406-15. [PMID: 23574721 PMCID: PMC3674068 DOI: 10.4161/cc.24516] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Revised: 03/28/2013] [Accepted: 04/01/2013] [Indexed: 12/18/2022] Open
Abstract
Loss of the tumor suppressor PTEN is observed in many human cancers that display increased chromosome instability and aneuploidy. The subcellular fractions of PTEN are associated with different functions that regulate cell growth, invasion and chromosome stability. In this study, we show a novel role for PTEN in regulating mitotic centrosomes. PTEN localization at mitotic centrosomes peaks between prophase and metaphase, paralleling the centrosomal localization of PLK-1 and γ-tubulin and coinciding with the time frame of centrosome maturation. In primary keratinocytes, knockdown of PTEN increased whole-cell levels of γ-tubulin and PLK-1 in an Akt-dependent manner and had little effect on recruitment of either protein to mitotic centrosomes. Conversely, knockdown of PTEN reduced centrosomal levels of pericentrin in an Akt-independent manner. Inhibition of Akt activation with MK2206 reduced the whole-cell and centrosome levels of PLK-1 and γ-tubulin and also prevented the recruitment of PTEN to mitotic centrosomes. This reduction in centrosome-associated proteins upon inhibition of Akt activity may contribute to the increase in defects in centrosome number and separation observed in metaphase cells. Concomitant PTEN knockdown and Akt inhibition reduced the frequency of metaphase cells with centrosome defects when compared with MK2206 treatment alone, indicating that both PTEN and pAkt are required to properly regulate centrosome composition during mitosis. The findings presented in this study demonstrate a novel role for PTEN and Akt in controlling centrosome composition and integrity during mitosis and provide insight into how PTEN functions as a multifaceted tumor suppressor.
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Affiliation(s)
- Mary K. Leonard
- Department of Biochemistry and Molecular Biology; Boonshoft School of Medicine; Wright State University; Dayton, OH USA
| | - Natasha T. Hill
- Department of Biochemistry and Molecular Biology; Boonshoft School of Medicine; Wright State University; Dayton, OH USA
| | - Paula A. Bubulya
- Department of Biological Sciences; Wright State University; Dayton, OH USA
| | - Madhavi P. Kadakia
- Department of Biochemistry and Molecular Biology; Boonshoft School of Medicine; Wright State University; Dayton, OH USA
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