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Gong T, McNally KL, Konanoor S, Peraza A, Bailey C, Redemann S, McNally FJ. Roles of Tubulin Concentration during Prometaphase and Ran-GTP during Anaphase of Caenorhabditis elegans Meiosis. Life Sci Alliance 2024; 7:e202402884. [PMID: 38960623 PMCID: PMC11222656 DOI: 10.26508/lsa.202402884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2024] [Revised: 06/25/2024] [Accepted: 06/26/2024] [Indexed: 07/05/2024] Open
Abstract
In many animal species, the oocyte meiotic spindle, which is required for chromosome segregation, forms without centrosomes. In some systems, Ran-GEF on chromatin initiates spindle assembly. We found that in Caenorhabditis elegans oocytes, endogenously-tagged Ran-GEF dissociates from chromatin during spindle assembly but re-associates during meiotic anaphase. Meiotic spindle assembly occurred after auxin-induced degradation of Ran-GEF, but anaphase I was faster than controls and extrusion of the first polar body frequently failed. In search of a possible alternative pathway for spindle assembly, we found that soluble tubulin concentrates in the nuclear volume during germinal vesicle breakdown. We found that the concentration of soluble tubulin in the metaphase spindle region is enclosed by ER sheets which exclude cytoplasmic organelles including mitochondria and yolk granules. Measurement of the volume occupied by yolk granules and mitochondria indicated that volume exclusion would be sufficient to explain the concentration of tubulin in the spindle volume. We suggest that this concentration of soluble tubulin may be a redundant mechanism promoting spindle assembly near chromosomes.
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Affiliation(s)
- Ting Gong
- https://ror.org/05rrcem69 Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA, USA
| | - Karen L McNally
- https://ror.org/05rrcem69 Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA, USA
| | - Siri Konanoor
- https://ror.org/05rrcem69 Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA, USA
| | - Alma Peraza
- https://ror.org/05rrcem69 Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA, USA
| | - Cynthia Bailey
- https://ror.org/05rrcem69 Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA, USA
| | - Stefanie Redemann
- https://ror.org/0153tk833 Department of Cell Biology, University of Virginia, School of Medicine, Charlottesville, VA, USA
| | - Francis J McNally
- https://ror.org/05rrcem69 Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA, USA
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Gong T, McNally KL, Konanoor S, Peraza A, Bailey C, Redemann S, McNally FJ. Roles of Tubulin Concentration during Prometaphase and Ran-GTP during Anaphase of C. elegans meiosis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.19.590357. [PMID: 38659754 PMCID: PMC11042349 DOI: 10.1101/2024.04.19.590357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
In many animal species, the oocyte meiotic spindle, which is required for chromosome segregation, forms without centrosomes. In some systems, Ran-GEF on chromatin initiates spindle assembly. We found that in C. elegans oocytes, endogenously-tagged Ran-GEF dissociates from chromatin during spindle assembly but re-associates during meiotic anaphase. Meiotic spindle assembly occurred after auxin-induced degradation of Ran-GEF but anaphase I was faster than controls and extrusion of the first polar body frequently failed. In search of a possible alternative pathway for spindle assembly, we found that soluble tubulin concentrates in the nuclear volume during germinal vesicle breakdown. We found that the concentration of soluble tubulin in the metaphase spindle region is enclosed by ER sheets which exclude cytoplasmic organelles including mitochondria and yolk granules. Measurement of the volume occupied by yolk granules and mitochondria indicated that volume exclusion would be sufficient to explain the concentration of tubulin in the spindle volume. We suggest that this concentration of soluble tubulin may be a redundant mechanism promoting spindle assembly near chromosomes.
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Affiliation(s)
- Ting Gong
- Department of Molecular and Cellular Biology, university of California, Davis, Davis, CA 95616, USA
| | - Karen L McNally
- Department of Molecular and Cellular Biology, university of California, Davis, Davis, CA 95616, USA
| | - Siri Konanoor
- Department of Molecular and Cellular Biology, university of California, Davis, Davis, CA 95616, USA
| | - Alma Peraza
- Department of Molecular and Cellular Biology, university of California, Davis, Davis, CA 95616, USA
| | - Cynthia Bailey
- Department of Molecular and Cellular Biology, university of California, Davis, Davis, CA 95616, USA
| | - Stefanie Redemann
- Department of Cell Biology, University of Virginia, School of Medicine, Charlottesville, VA, USA
| | - Francis J McNally
- Department of Molecular and Cellular Biology, university of California, Davis, Davis, CA 95616, USA
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Huang SK, Rubinstein JL, Kay LE. Cryo-EM of the Nucleosome Core Particle Bound to Ran-RCC1 Reveals a Dynamic Complex. Biochemistry 2024; 63:880-892. [PMID: 38501608 DOI: 10.1021/acs.biochem.3c00724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/20/2024]
Abstract
Ras-related nuclear protein (Ran) is a member of the Ras superfamily of small guanosine triphosphatases (GTPases) and a regulator of multiple cellular processes. In healthy cells, the GTP-bound form of Ran is concentrated at chromatin, creating a Ran•GTP gradient that provides the driving force for nucleocytoplasmic transport, mitotic spindle assembly, and nuclear envelope formation. The Ran•GTP gradient is maintained by the regulator of chromatin condensation 1 (RCC1), a guanine nucleotide exchange factor that accelerates GDP/GTP exchange in Ran. RCC1 interacts with nucleosomes, which are the fundamental repeating units of eukaryotic chromatin. Here, we present a cryo-EM analysis of a trimeric complex composed of the nucleosome core particle (NCP), RCC1, and Ran. While the contacts between RCC1 and Ran in the complex are preserved compared with a previously determined structure of RCC1-Ran, our study reveals that RCC1 and Ran interact dynamically with the NCP and undergo rocking motions on the nucleosome surface. Furthermore, the switch 1 region of Ran, which plays an important role in mediating conformational changes associated with the substitution of GDP and GTP nucleotides in Ras family members, appears to undergo disorder-order transitions and forms transient contacts with the C-terminal helix of histone H2B. Nucleotide exchange assays performed in the presence and absence of NCPs are not consistent with an active role for nucleosomes in nucleotide exchange, at least in vitro. Instead, the nucleosome stabilizes RCC1 and serves as a hub that concentrates RCC1 and Ran to promote efficient Ran•GDP to Ran•GTP conversion.
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Affiliation(s)
- Shuya Kate Huang
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
- Department of Chemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
- Hospital for Sick Children, Program in Molecular Medicine, Toronto, ON M5G 1X8, Canada
| | - John L Rubinstein
- Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
- Hospital for Sick Children, Program in Molecular Medicine, Toronto, ON M5G 1X8, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, ON M5G 1L7, Canada
| | - Lewis E Kay
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
- Department of Chemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
- Hospital for Sick Children, Program in Molecular Medicine, Toronto, ON M5G 1X8, Canada
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4
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Gopinathan G, Xu Q, Luan X, Diekwisch TGH. CFDP1 regulates the stability of pericentric heterochromatin thereby affecting RAN GTPase activity and mitotic spindle formation. PLoS Biol 2024; 22:e3002574. [PMID: 38630655 PMCID: PMC11023358 DOI: 10.1371/journal.pbio.3002574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Accepted: 03/02/2024] [Indexed: 04/19/2024] Open
Abstract
The densely packed centromeric heterochromatin at minor and major satellites is comprised of H3K9me2/3 histones, the heterochromatin protein HP1α, and histone variants. In the present study, we sought to determine the mechanisms by which condensed heterochromatin at major and minor satellites stabilized by the chromatin factor CFDP1 affects the activity of the small GTPase Ran as a requirement for spindle formation. CFDP1 colocalized with heterochromatin at major and minor satellites and was essential for the structural stability of centromeric heterochromatin. Loss of CENPA, HP1α, and H2A.Z heterochromatin components resulted in decreased binding of the spindle nucleation facilitator RCC1 to minor and major satellite repeats. Decreased RanGTP levels as a result of diminished RCC1 binding interfered with chromatin-mediated microtubule nucleation at the onset of mitotic spindle formation. Rescuing chromatin H2A.Z levels in cells and mice lacking CFDP1 through knock-down of the histone chaperone ANP32E not only partially restored RCC1-dependent RanGTP levels but also alleviated CFDP1-knockout-related craniofacial defects and increased microtubule nucleation in CFDP1/ANP32E co-silenced cells. Together, these studies provide evidence for a direct link between condensed heterochromatin at major and minor satellites and microtubule nucleation through the chromatin protein CFDP1.
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Affiliation(s)
- Gokul Gopinathan
- School of Medicine and Dentistry, University of Rochester, Rochester, New York, United States of America
| | - Qian Xu
- School of Medicine and Dentistry, University of Rochester, Rochester, New York, United States of America
| | - Xianghong Luan
- School of Medicine and Dentistry, University of Rochester, Rochester, New York, United States of America
| | - Thomas G. H. Diekwisch
- School of Medicine and Dentistry, University of Rochester, Rochester, New York, United States of America
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Klongnoi B, Bhattarai BP, Juengsomjit R, Meesakul O, Poomsawat S, Janebodin K, Khovidhunkit SOP. Preliminary Study on the Expression of CLLD7 and CHC1L Proteins in Oral Squamous Cell Carcinoma. Eur J Dent 2024; 18:297-303. [PMID: 37311552 PMCID: PMC10959600 DOI: 10.1055/s-0043-1768468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023] Open
Abstract
OBJECTIVE This study aimed to preliminarily evaluate the expression of two putative tumor suppressor proteins, including chronic lymphocytic leukemia deletion gene 7 (CLLD7) and chromosome condensation 1-like (CHC1L) proteins in oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS Expression of CLLD7 and CHC1L proteins was analyzed in 19 OSCC and 12 normal oral mucosa (NOM) using immunohistochemistry. The percentage of positive cells and intensity of staining were semiquantitatively assessed and expressed with an immunoreactive score. The number of positive cells at various subcellular localizations was evaluated and presented in percentages. The immunoreactivity scores and percentages of positive cells at various localizations were compared between the normal and OSCC groups with statistical significance at p-value less than 0.05. RESULTS According to immunohistochemical analysis, the immunoreactivity scores for both CLLD7 and CHC1L were higher in NOM than those of OSCC. Analysis of CLLD7 localization revealed predominant nuclear staining at basal and parabasal areas in NOM, whereas more cytoplasmic staining was observed in OSCC. For CHC1L, nuclear staining was prominent in NOM. In contrast, significantly increased plasma membrane staining was detected in OSCC. CONCLUSION The expression of CLLD7 and CHC1L proteins was reduced in OSCC. Alterations in the subcellular localization of these two proteins in OSCC were also demonstrated. These preliminary results suggest that CLLD7 and CHC1L are aberrantly expressed in OSCC. The precise mechanisms of these putative tumor suppressor proteins in OSCC require future studies.
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Affiliation(s)
- Boworn Klongnoi
- Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Mahidol University, Bangkok, Thailand
| | - Bishwa Prakash Bhattarai
- Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Mahidol University, Bangkok, Thailand
- Department of Clinical Dentistry, Walailak University International College of Dentistry, Walailak University, Bangkok, Thailand
| | - Rachai Juengsomjit
- Department of Oral and Maxillofacial Pathology, Faculty of Dentistry, Mahidol University, Bangkok, Thailand
| | - Ounruean Meesakul
- Department of Oral and Maxillofacial Pathology, Faculty of Dentistry, Mahidol University, Bangkok, Thailand
| | - Sopee Poomsawat
- Department of Oral and Maxillofacial Pathology, Faculty of Dentistry, Mahidol University, Bangkok, Thailand
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Bannoura SF, Aboukameel A, Khan HY, Uddin MH, Jang H, Beal E, Thangasamy A, Kim S, Wagner KU, Mohammad R, Al-Hallak MN, Pasche BC, Azmi AS. Regulator of Chromosome Condensation (RCC1) a novel therapeutic target in pancreatic ductal adenocarcinoma drives tumor progression via the c-Myc-RCC1-Ran axis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.18.572102. [PMID: 38187605 PMCID: PMC10769244 DOI: 10.1101/2023.12.18.572102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignancy with limited therapeutic options. Here we for the first time evaluated the role of regulator of chromosome condensation 1 (RCC1) in PDAC subsistence and drug resistance. RCC1 expression was found to be elevated in PDAC tissues in comparison with normal pancreatic tissues and was linked to poor prognosis. RCC1 silencing in a panel of PDAC cells by RNA interference and CRISPR-Cas9 resulted in reduced cellular proliferation in 2D and 3D cultures. RCC1 KD reduced migratory and clonogenic ability, enhanced apoptosis, and altered cell cycle distribution in human PDAC cells as well as cells isolated from the LSL-Kras G12D/+; LSL-Trp53 R172H/+ ;Pdx1-Cre (KPC) mouse tumors. Subcutaneous cell-derived xenografts show significantly attenuated growth of RCC1 KO tumors. Mechanistically, RCC1 knockdown resulted in disruption of subcellular Ran distribution indicating that stable nuclear Ran localization is critical for PDAC proliferation. Nuclear and cytosolic proteomic analysis revealed altered subcellular proteome in RCC1 KD KPC-tumor-derived cells. Altered cytoplasmic protein pathways include several metabolic pathways and PI3K-Akt signaling pathway. Pathways enriched in altered nuclear proteins include cell cycle, mitosis, and RNA regulation. RNA sequencing of RCC1 KO cells showed widespread transcriptional alterations. Upstream of RCC1, c-Myc activates the RCC1-Ran axis, and RCC1 KO enhances the sensitivity of PDAC cells to c-Myc inhibitors. Finally, RCC1 knockdown resulted in the sensitization of PDAC cells to Gemcitabine. Our results indicate that RCC1 is a potential therapeutic target in PDAC that warrants further clinical investigations.
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Yang Y, Guo L, Chen L, Gong B, Jia D, Sun Q. Nuclear transport proteins: structure, function, and disease relevance. Signal Transduct Target Ther 2023; 8:425. [PMID: 37945593 PMCID: PMC10636164 DOI: 10.1038/s41392-023-01649-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Revised: 09/13/2023] [Accepted: 09/14/2023] [Indexed: 11/12/2023] Open
Abstract
Proper subcellular localization is crucial for the functioning of biomacromolecules, including proteins and RNAs. Nuclear transport is a fundamental cellular process that regulates the localization of many macromolecules within the nuclear or cytoplasmic compartments. In humans, approximately 60 proteins are involved in nuclear transport, including nucleoporins that form membrane-embedded nuclear pore complexes, karyopherins that transport cargoes through these complexes, and Ran system proteins that ensure directed and rapid transport. Many of these nuclear transport proteins play additional and essential roles in mitosis, biomolecular condensation, and gene transcription. Dysregulation of nuclear transport is linked to major human diseases such as cancer, neurodegenerative diseases, and viral infections. Selinexor (KPT-330), an inhibitor targeting the nuclear export factor XPO1 (also known as CRM1), was approved in 2019 to treat two types of blood cancers, and dozens of clinical trials of are ongoing. This review summarizes approximately three decades of research data in this field but focuses on the structure and function of individual nuclear transport proteins from recent studies, providing a cutting-edge and holistic view on the role of nuclear transport proteins in health and disease. In-depth knowledge of this rapidly evolving field has the potential to bring new insights into fundamental biology, pathogenic mechanisms, and therapeutic approaches.
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Affiliation(s)
- Yang Yang
- Department of Pulmonary and Critical Care Medicine, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Lu Guo
- Department of Pulmonary and Critical Care Medicine, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Lin Chen
- Department of Pulmonary and Critical Care Medicine, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Bo Gong
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and Department of Laboratory Medicine, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
- Research Unit for Blindness Prevention of Chinese Academy of Medical Sciences (2019RU026), Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, Chengdu, China
| | - Da Jia
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Department of Pediatrics, West China Second University Hospital, State Key Laboratory of Biotherapy, Sichuan University, Chengdu, China.
| | - Qingxiang Sun
- Department of Pulmonary and Critical Care Medicine, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China.
- Department of Pathology, State Key Laboratory of Biotherapy and Cancer Centre, West China Hospital, Sichuan University, and Collaborative Innovation Centre of Biotherapy, Chengdu, China.
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8
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Chen P, Huang R, Hazbun TR. Unlocking the Mysteries of Alpha-N-Terminal Methylation and its Diverse Regulatory Functions. J Biol Chem 2023:104843. [PMID: 37209820 PMCID: PMC10293735 DOI: 10.1016/j.jbc.2023.104843] [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: 08/17/2022] [Revised: 05/11/2023] [Accepted: 05/12/2023] [Indexed: 05/22/2023] Open
Abstract
Protein post-translation modifications (PTMs) are a critical regulatory mechanism of protein function. Protein α-N-terminal (Nα) methylation is a conserved PTM across prokaryotes and eukaryotes. Studies of the Nα methyltransferases responsible for Να methylation and their substrate proteins have shown that the PTM involves diverse biological processes, including protein synthesis and degradation, cell division, DNA damage response, and transcription regulation. This review provides an overview of the progress toward the regulatory function of Να methyltransferases and their substrate landscape. More than 200 proteins in humans and 45 in yeast are potential substrates for protein Nα methylation based on the canonical recognition motif, XP[KR]. Based on recent evidence for a less stringent motif requirement, the number of substrates might be increased, but further validation is needed to solidify this concept. A comparison of the motif in substrate orthologs in selected eukaryotic species indicates intriguing gain and loss of the motif across the evolutionary landscape. We discuss the state of knowledge in the field that has provided insights into the regulation of protein Να methyltransferases and their role in cellular physiology and disease. We also outline the current research tools that are key to understanding Να methylation. Finally, challenges are identified and discussed that would aid in unlocking a system-level view of the roles of Να methylation in diverse cellular pathways.
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Affiliation(s)
- Panyue Chen
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana 47907, United States
| | - Rong Huang
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana 47907, United States; Purdue University Center for Cancer Research, Purdue University, West Lafayette, Indiana 47907, United States
| | - Tony R Hazbun
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana 47907, United States; Purdue University Center for Cancer Research, Purdue University, West Lafayette, Indiana 47907, United States.
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9
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Wu J, Larreategui-Aparicio A, Lambers MLA, Bodor DL, Klaasen SJ, Tollenaar E, de Ruijter-Villani M, Kops GJPL. Microtubule nucleation from the fibrous corona by LIC1-pericentrin promotes chromosome congression. Curr Biol 2023; 33:912-925.e6. [PMID: 36720222 PMCID: PMC10017265 DOI: 10.1016/j.cub.2023.01.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 11/17/2022] [Accepted: 01/06/2023] [Indexed: 01/31/2023]
Abstract
Error-free chromosome segregation in mitosis and meiosis relies on the assembly of a microtubule-based spindle that interacts with kinetochores to guide chromosomes to the cell equator before segregation in anaphase. Microtubules sprout from nucleation sites such as centrosomes, but kinetochores can also promote microtubule formation. It is unclear, however, how kinetochore-derived microtubules are generated and what their role is in chromosome segregation. Here, we show that the transient outer-kinetochore meshwork known as the fibrous corona serves as an autonomous microtubule nucleation platform. The fibrous corona is essential for the nucleation of kinetochore-derived microtubules, and when dissociated from the core kinetochore, it retains microtubule nucleation capacity. Nucleation relies on a fibrous-corona-bound pool of the LIC1 subunit of the dynein motor complex, which interacts with the γ-tubulin-tethering protein pericentrin (PCNT). PCNT is essential for microtubule nucleation from fibrous coronas, and in centrosome-depleted cells, where nearly all mitotic nucleation occurs at fibrous coronas, chromosome congression is fully dependent on PCNT. We further show that chromosomes in bovine oocytes, which naturally lack centrosomes, have highly expanded fibrous coronas that drive chromosome-derived microtubule nucleation. Preventing fibrous corona expansion in these cells impairs chromosome congression and causes spindle assembly defects. Our results show that fibrous coronas are autonomous microtubule-organizing centers that are important for spindle assembly, which may be especially relevant in acentrosomal cells such as oocytes.
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Affiliation(s)
- Jingchao Wu
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences (KNAW), Uppsalalaan 8, 3584CT Utrecht, the Netherlands; University Medical Center Utrecht, Heidelberglaan 100, 3584CX Utrecht, the Netherlands; Oncode Institute, Jaarbeursplein 6, 3521AL Utrecht, the Netherlands
| | - Ainhoa Larreategui-Aparicio
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences (KNAW), Uppsalalaan 8, 3584CT Utrecht, the Netherlands; University Medical Center Utrecht, Heidelberglaan 100, 3584CX Utrecht, the Netherlands; Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584CL Utrecht, the Netherlands
| | - Maaike L A Lambers
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences (KNAW), Uppsalalaan 8, 3584CT Utrecht, the Netherlands; University Medical Center Utrecht, Heidelberglaan 100, 3584CX Utrecht, the Netherlands; Oncode Institute, Jaarbeursplein 6, 3521AL Utrecht, the Netherlands
| | - Dani L Bodor
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences (KNAW), Uppsalalaan 8, 3584CT Utrecht, the Netherlands; University Medical Center Utrecht, Heidelberglaan 100, 3584CX Utrecht, the Netherlands; Oncode Institute, Jaarbeursplein 6, 3521AL Utrecht, the Netherlands
| | - Sjoerd J Klaasen
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences (KNAW), Uppsalalaan 8, 3584CT Utrecht, the Netherlands; University Medical Center Utrecht, Heidelberglaan 100, 3584CX Utrecht, the Netherlands; Oncode Institute, Jaarbeursplein 6, 3521AL Utrecht, the Netherlands
| | - Eveline Tollenaar
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584CL Utrecht, the Netherlands
| | - Marta de Ruijter-Villani
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences (KNAW), Uppsalalaan 8, 3584CT Utrecht, the Netherlands; University Medical Center Utrecht, Heidelberglaan 100, 3584CX Utrecht, the Netherlands; Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584CL Utrecht, the Netherlands; Division of Woman and Baby, Department of Obstetrics and Gynecology, University Medical Centre Utrecht, Heidelberglaan 100, 3584CX Utrecht, the Netherlands
| | - Geert J P L Kops
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences (KNAW), Uppsalalaan 8, 3584CT Utrecht, the Netherlands; University Medical Center Utrecht, Heidelberglaan 100, 3584CX Utrecht, the Netherlands; Oncode Institute, Jaarbeursplein 6, 3521AL Utrecht, the Netherlands.
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10
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El-Tanani M, Nsairat H, Mishra V, Mishra Y, Aljabali AAA, Serrano-Aroca Á, Tambuwala MM. Ran GTPase and Its Importance in Cellular Signaling and Malignant Phenotype. Int J Mol Sci 2023; 24:ijms24043065. [PMID: 36834476 PMCID: PMC9968026 DOI: 10.3390/ijms24043065] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 01/10/2023] [Accepted: 01/11/2023] [Indexed: 02/08/2023] Open
Abstract
Ran is a member of the Ras superfamily of proteins, which primarily regulates nucleocytoplasmic trafficking and mediates mitosis by regulating spindle formation and nuclear envelope (NE) reassembly. Therefore, Ran is an integral cell fate determinant. It has been demonstrated that aberrant Ran expression in cancer is a result of upstream dysregulation of the expression of various factors, such as osteopontin (OPN), and aberrant activation of various signaling pathways, including the extracellular-regulated kinase/mitogen-activated protein kinase (ERK/MEK) and phosphatidylinositol 3-kinase/Protein kinase B (PI3K/Akt) pathways. In vitro, Ran overexpression has severe effects on the cell phenotype, altering proliferation, adhesion, colony density, and invasion. Therefore, Ran overexpression has been identified in numerous types of cancer and has been shown to correlate with tumor grade and the degree of metastasis present in various cancers. The increased malignancy and invasiveness have been attributed to multiple mechanisms. Increased dependence on Ran for spindle formation and mitosis is a consequence of the upregulation of these pathways and the ensuing overexpression of Ran, which increases cellular dependence on Ran for survival. This increases the sensitivity of cells to changes in Ran concentration, with ablation being associated with aneuploidy, cell cycle arrest, and ultimately, cell death. It has also been demonstrated that Ran dysregulation influences nucleocytoplasmic transport, leading to transcription factor misallocation. Consequently, patients with tumors that overexpress Ran have been shown to have a higher malignancy rate and a shorter survival time compared to their counterparts.
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Affiliation(s)
- Mohamed El-Tanani
- Pharmacological and Diagnostic Research Centre, Faculty of Pharmacy, Al-Ahliyya Amman University, Amman 19328, Jordan
- Correspondence:
| | - Hamdi Nsairat
- Pharmacological and Diagnostic Research Centre, Faculty of Pharmacy, Al-Ahliyya Amman University, Amman 19328, Jordan
| | - Vijay Mishra
- School of Pharmaceutical Sciences, Lovely Professional University, Phagwara 144411, India
| | - Yachana Mishra
- Department of Zoology, School of Bioengineering and Biosciences, Lovely Professional University, Phagwara 144411, India
| | - Alaa A. A. Aljabali
- Department of Pharmaceutics & Pharmaceutical Technology, Yarmouk University, Irbid 21163, Jordan
| | - Ángel Serrano-Aroca
- Biomaterials and Bioengineering Laboratory, Centro de Investigación Traslacional San Alberto Magno, Universidad Católica de Valencia San Vicente Mártir, c/Guillem de Castro 94, 46001 Valencia, Spain
| | - Murtaza M. Tambuwala
- Lincoln Medical School, University of Lincoln, Brayford Pool, Lincoln LN6 7TS, UK
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11
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Holzer G, Antonin W. Nup50 plays more than one instrument. Cell Cycle 2022; 21:1785-1794. [PMID: 35549614 PMCID: PMC9359400 DOI: 10.1080/15384101.2022.2074742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Nup50 is nuclear pore complex component localized to the nuclear side of the pore and in the nucleoplasm. It has been characterized as an auxiliary factor in nuclear transport reactions. Our recent work indicates that it interacts with and stimulates RCC1, the sole guanine nucleotide exchange factor for the GTPase Ran. Here, we discuss how this interaction might contribute to Nup50 function in nuclear transport but also its other functions like control of gene expression, cell cycle and DNA damage repair.
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Affiliation(s)
- Guillaume Holzer
- Institute of Biochemistry and Molecular Cell Biology, Medical School, RWTH Aachen University, Aachen, Germany
| | - Wolfram Antonin
- Institute of Biochemistry and Molecular Cell Biology, Medical School, RWTH Aachen University, Aachen, Germany
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12
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Isali I, McClellan P, Calaway A, Prunty M, Abbosh P, Mishra K, Ponsky L, Markt S, Psutka SP, Bukavina L. Gene network profiling in muscle-invasive bladder cancer: A systematic review and meta-analysis. Urol Oncol 2022; 40:197.e11-197.e23. [PMID: 35039218 PMCID: PMC10123538 DOI: 10.1016/j.urolonc.2021.11.003] [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: 09/12/2021] [Revised: 10/17/2021] [Accepted: 11/02/2021] [Indexed: 10/19/2022]
Abstract
BACKGROUND Determining meta-analysis of transcriptional profiling of muscle-invasive bladder cancer (MIBC) through Gene Expression Omnibus (GEO) datasets has not been investigated. This study aims to define gene expression profiles in MIBC and to identify potential candidate genes and pathways. OBJECTIVES To review and evaluate gene expression studies in MIBC through publicly available RNA sequencing (RNA-Seq) and microarray data in order to identify potential prognostic and therapeutic targets for MIBC. METHODS A systematic literature search of the Ovid MEDLINE, PubMed, and Wiley Cochrane Central Register of Controlled Trials databases was performed using the terms "gene," "gene expression," and "bladder cancer" January 1, 1990 through March 2021 focused on populations with MIBC. RESULTS In the final analysis, GEO datasets were included. Fixed effect model was employed in the meta-analysis. Gene networking connections and gene-set functional analyses of the identified genes as differentially expressed in MIBC were performed using ImaGEO and GeneMANIA software. A heatmap for the upregulated and downregulated genes was generated along with the correlated pathways. CONCLUSION A total of 9 genes were reported in this analysis. Six genes were reported as upregulated (ProTα, SPINT1, UBE2E1, RAB25, KPNB1, HDAC1) and 3 genes as downregulated (NUP188, IPO13, NUP124). Genes were found to be involved in "ubiquitin mediated proteolysis," "protein processing in endoplasmic reticulum," "transcriptional misregulation in cancer," and "RNA transport" pathways.
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Affiliation(s)
- Ilaha Isali
- Department of Urology, University Hospitals Cleveland Medical Center, Case Western Reserve University, Cleveland, OH
| | - Phillip McClellan
- Department of Mechanical and Aerospace Engineering, Case Western Reserve University, Cleveland, OH
| | - Adam Calaway
- Department of Urology, University Hospitals Cleveland Medical Center, Case Western Reserve University, Cleveland, OH; Case Comprehensive Cancer Center, Case Western Reserve School of Medicine, Cleveland, OH
| | - Megan Prunty
- Department of Urology, University Hospitals Cleveland Medical Center, Case Western Reserve University, Cleveland, OH
| | - Phillip Abbosh
- Department of Urology, Fox Chase Cancer Center, Philadelphia, PA
| | - Kirtishri Mishra
- Department of Urology, Fox Chase Cancer Center, Philadelphia, PA
| | - Lee Ponsky
- Department of Urology, University Hospitals Cleveland Medical Center, Case Western Reserve University, Cleveland, OH; Case Comprehensive Cancer Center, Case Western Reserve School of Medicine, Cleveland, OH
| | - Sarah Markt
- Department of Population and Quantitative Health Science, Case Western Reserve School of Medicine, Cleveland, OH
| | - Sarah P Psutka
- Department of Urology, University of Washington School of Medicine, Seattle, WA
| | - Laura Bukavina
- Department of Urology, University Hospitals Cleveland Medical Center, Case Western Reserve University, Cleveland, OH; Case Comprehensive Cancer Center, Case Western Reserve School of Medicine, Cleveland, OH.
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13
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The intricate roles of RCC1 in normal cells and cancer cells. Biochem Soc Trans 2022; 50:83-93. [PMID: 35191966 DOI: 10.1042/bst20210861] [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: 10/26/2021] [Revised: 01/24/2022] [Accepted: 02/02/2022] [Indexed: 11/17/2022]
Abstract
RCC1 (regulator of chromosome condensation 1) is a highly conserved chromatin-binding protein and the only known guanine-nucleotide exchange factor of Ran (a nuclear Ras homolog). RCC1 plays an essential role in the regulation of cell cycle-related activities such as nuclear envelope formation, nuclear pore complex and spindle assembly, and nucleocytoplasmic transport. Over the last decade, increasing evidence has emerged highlighting the potential relevance of RCC1 to carcinogenesis, especially cervical, lung, and breast cancer. In this review, we briefly discuss the roles of RCC1 in both normal and tumor cells based on articles published in recent years, followed by a brief overview of future perspectives in the field.
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14
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Clarke PR. Keep it focused: PRMT6 drives the localization of RCC1 to chromosomes to facilitate mitosis, cell proliferation, and tumorigenesis. Mol Cell 2021; 81:1128-1129. [PMID: 33740472 DOI: 10.1016/j.molcel.2021.02.026] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Huang et al. (2021) identified a mechanism acting through the arginine methyltransferase PRMT6 that stabilizes the interaction of RCC1 with chromatin, promoting cell proliferation and tumorigenicity. Targeting this mechanism might enhance the treatment of tumors such as glioblastoma.
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Affiliation(s)
- Paul R Clarke
- The University of Queensland Diamantina Institute, Faculty of Medicine, The University of Queensland, Brisbane, QLD 4102, Australia.
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15
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Huang T, Yang Y, Song X, Wan X, Wu B, Sastry N, Horbinski CM, Zeng C, Tiek D, Goenka A, Liu F, Brennan CW, Kessler JA, Stupp R, Nakano I, Sulman EP, Nishikawa R, James CD, Zhang W, Xu W, Hu B, Cheng SY. PRMT6 methylation of RCC1 regulates mitosis, tumorigenicity, and radiation response of glioblastoma stem cells. Mol Cell 2021; 81:1276-1291.e9. [PMID: 33539787 DOI: 10.1016/j.molcel.2021.01.015] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 11/02/2020] [Accepted: 01/11/2021] [Indexed: 12/22/2022]
Abstract
Aberrant cell proliferation is a hallmark of cancer, including glioblastoma (GBM). Here we report that protein arginine methyltransferase (PRMT) 6 activity is required for the proliferation, stem-like properties, and tumorigenicity of glioblastoma stem cells (GSCs), a subpopulation in GBM critical for malignancy. We identified a casein kinase 2 (CK2)-PRMT6-regulator of chromatin condensation 1 (RCC1) signaling axis whose activity is an important contributor to the stem-like properties and tumor biology of GSCs. CK2 phosphorylates and stabilizes PRMT6 through deubiquitylation, which promotes PRMT6 methylation of RCC1, which in turn is required for RCC1 association with chromatin and activation of RAN. Disruption of this pathway results in defects in mitosis. EPZ020411, a specific small-molecule inhibitor for PRMT6, suppresses RCC1 arginine methylation and improves the cytotoxic activity of radiotherapy against GSC brain tumor xenografts. This study identifies a CK2α-PRMT6-RCC1 signaling axis that can be therapeutically targeted in the treatment of GBM.
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Affiliation(s)
- Tianzhi Huang
- The Ken & Ruth Davee Department of Neurology, The Lou and Jean Malnati Brain Tumor Institute, The Robert H. Lurie Comprehensive Cancer Center, Simpson Querrey Institute for Epigenetics, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Yongyong Yang
- The Ken & Ruth Davee Department of Neurology, The Lou and Jean Malnati Brain Tumor Institute, The Robert H. Lurie Comprehensive Cancer Center, Simpson Querrey Institute for Epigenetics, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Xiao Song
- The Ken & Ruth Davee Department of Neurology, The Lou and Jean Malnati Brain Tumor Institute, The Robert H. Lurie Comprehensive Cancer Center, Simpson Querrey Institute for Epigenetics, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Xuechao Wan
- The Ken & Ruth Davee Department of Neurology, The Lou and Jean Malnati Brain Tumor Institute, The Robert H. Lurie Comprehensive Cancer Center, Simpson Querrey Institute for Epigenetics, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Bingli Wu
- The Ken & Ruth Davee Department of Neurology, The Lou and Jean Malnati Brain Tumor Institute, The Robert H. Lurie Comprehensive Cancer Center, Simpson Querrey Institute for Epigenetics, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Namratha Sastry
- The Ken & Ruth Davee Department of Neurology, The Lou and Jean Malnati Brain Tumor Institute, The Robert H. Lurie Comprehensive Cancer Center, Simpson Querrey Institute for Epigenetics, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Craig M Horbinski
- Department of Pathology, The Lou and Jean Malnati Brain Tumor Institute, The Robert H. Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA; Department of Neurological Surgery, The Lou and Jean Malnati Brain Tumor Institute, The Robert H. Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Chang Zeng
- Department of Preventive Medicine, The Robert H. Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Deanna Tiek
- The Ken & Ruth Davee Department of Neurology, The Lou and Jean Malnati Brain Tumor Institute, The Robert H. Lurie Comprehensive Cancer Center, Simpson Querrey Institute for Epigenetics, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Anshika Goenka
- The Ken & Ruth Davee Department of Neurology, The Lou and Jean Malnati Brain Tumor Institute, The Robert H. Lurie Comprehensive Cancer Center, Simpson Querrey Institute for Epigenetics, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Fabao Liu
- McArdle Laboratory for Cancer Research, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA
| | - Cameron W Brennan
- Human Oncology and Pathogenesis Program, Department of Neurosurgery, Brain Tumor Center, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - John A Kessler
- The Ken & Ruth Davee Department of Neurology, The Lou and Jean Malnati Brain Tumor Institute, The Robert H. Lurie Comprehensive Cancer Center, Simpson Querrey Institute for Epigenetics, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Roger Stupp
- The Ken & Ruth Davee Department of Neurology, The Lou and Jean Malnati Brain Tumor Institute, The Robert H. Lurie Comprehensive Cancer Center, Simpson Querrey Institute for Epigenetics, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA; Department of Neurological Surgery, The Lou and Jean Malnati Brain Tumor Institute, The Robert H. Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Ichiro Nakano
- Department of Neurosurgery, The University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Erik P Sulman
- Department of Radiation Oncology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Ryo Nishikawa
- Department of Neuro-Oncology/Neurosurgery, Saitama Medical University International Medical Center, Saitama 350-1298, Japan
| | - Charles David James
- Department of Neurological Surgery, The Lou and Jean Malnati Brain Tumor Institute, The Robert H. Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Wei Zhang
- Department of Preventive Medicine, The Robert H. Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Wei Xu
- McArdle Laboratory for Cancer Research, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA
| | - Bo Hu
- The Ken & Ruth Davee Department of Neurology, The Lou and Jean Malnati Brain Tumor Institute, The Robert H. Lurie Comprehensive Cancer Center, Simpson Querrey Institute for Epigenetics, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA.
| | - Shi-Yuan Cheng
- The Ken & Ruth Davee Department of Neurology, The Lou and Jean Malnati Brain Tumor Institute, The Robert H. Lurie Comprehensive Cancer Center, Simpson Querrey Institute for Epigenetics, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA.
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16
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Characterization of novel USP6 gene rearrangements in a subset of so-called cellular fibroma of tendon sheath. Mod Pathol 2021; 34:13-19. [PMID: 32661296 DOI: 10.1038/s41379-020-0621-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 05/27/2020] [Accepted: 05/27/2020] [Indexed: 12/17/2022]
Abstract
Fibroma of tendon sheath (FTS) is an uncommon benign fibroblastic/myofibroblastic neoplasm that typically arises in the tenosynovial tissue of the distal extremities. Histologically, it is a well-circumscribed proliferation of spindle cells within collagenous stroma with peripheral slit-like vessels. Most examples are relatively hypocellular and more densely collagenous than nodular fasciitis; however, a cellular variant has been described, which has considerable morphologic overlap with nodular fasciitis and has been shown to harbor USP6 translocations in a subset of cases. The incidence of these rearrangements and the identity of the USP6 fusion partners have not been described in detail. In this study we evaluate 13 cases of cellular fibroma of tendon sheath by anchored multiplex PCR/next generation sequencing in order to detect potential gene fusions. Nucleic acids of adequate quality were obtained in 11 cases, demonstrating gene fusions in 7/11 (64%), all of which involve USP6 with a variety of partners, including PKM, RCC1, ASPN, COL1A1, COL3A1, and MYH9. Some unusual histomorphologic findings were present in a subset of cases including palisading growth pattern, epithelioid cells, and osteoclast-like multinucleated giant cells, particularly in the tumors with PKM and ASPN gene partners. Overall, the findings support a biologic relationship between cellular fibroma of tendon sheath and other lesions within the spectrum of USP6-rearranged neoplasms, particularly nodular fasciitis.
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17
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Wiegand T, Hyman AA. Drops and fibers - how biomolecular condensates and cytoskeletal filaments influence each other. Emerg Top Life Sci 2020; 4:247-261. [PMID: 33048111 PMCID: PMC7733666 DOI: 10.1042/etls20190174] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 09/16/2020] [Accepted: 09/17/2020] [Indexed: 12/13/2022]
Abstract
The cellular cytoskeleton self-organizes by specific monomer-monomer interactions resulting in the polymerization of filaments. While we have long thought about the role of polymerization in cytoskeleton formation, we have only begun to consider the role of condensation in cytoskeletal organization. In this review, we highlight how the interplay between polymerization and condensation leads to the formation of the cytoskeleton.
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Affiliation(s)
- Tina Wiegand
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
- Center for Systems Biology Dresden, Dresden, Germany
- Max Planck Institute for the Physics of Complex Systems, Dresden, Germany
| | - Anthony A Hyman
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
- Center for Systems Biology Dresden, Dresden, Germany
- Cluster of Excellence Physics of Life, TU Dresden, Dresden, Germany
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18
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Ren X, Jiang K, Zhang F. The Multifaceted Roles of RCC1 in Tumorigenesis. Front Mol Biosci 2020; 7:225. [PMID: 33102517 PMCID: PMC7522611 DOI: 10.3389/fmolb.2020.00225] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 08/11/2020] [Indexed: 01/31/2023] Open
Abstract
RCC1 (regulator of chromosome condensation 1) is the only known guanine nucleotide exchange factor of Ran, a nuclear Ras-like G protein. RCC1 combines with chromatin and Ran to establish a concentration gradient of RanGTP, thereby participating in a series of cell physiological activities. In this review, we discuss the structure of RCC1 and describe how RCC1 affects the formation and function of the nuclear envelope, spindle formation, and nuclear transport. We mainly focus on the effect of RCC1 on the cell cycle during tumorigenesis and the recent research progress that has been made in relation to different tumor types.
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Affiliation(s)
- Xuanqi Ren
- College of Life Sciences, Shanghai Normal University, Shanghai, China
| | - Kai Jiang
- College of Life Sciences, Shanghai Normal University, Shanghai, China
| | - Feng Zhang
- College of Life Sciences, Shanghai Normal University, Shanghai, China
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19
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Ems-McClung SC, Emch M, Zhang S, Mahnoor S, Weaver LN, Walczak CE. RanGTP induces an effector gradient of XCTK2 and importin α/β for spindle microtubule cross-linking. J Cell Biol 2020; 219:133528. [PMID: 31865374 PMCID: PMC7041689 DOI: 10.1083/jcb.201906045] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 10/21/2019] [Accepted: 11/08/2019] [Indexed: 01/04/2023] Open
Abstract
High RanGTP around chromatin is important for governing spindle assembly during meiosis and mitosis by releasing the inhibitory effects of importin α/β. Here we examine how the Ran gradient regulates Kinesin-14 function to control spindle organization. We show that Xenopus Kinesin-14, XCTK2, and importin α/β form an effector gradient that is highest at the poles and diminishes toward the chromatin, which is opposite the RanGTP gradient. Importin α and β preferentially inhibit XCTK2 antiparallel microtubule cross-linking and sliding by decreasing the microtubule affinity of the XCTK2 tail domain. This change in microtubule affinity enables RanGTP to target endogenous XCTK2 to the spindle. We propose that these combined actions of the Ran pathway are critical to promote Kinesin-14 parallel microtubule cross-linking to help focus spindle poles for efficient bipolar spindle assembly. Furthermore, our work illustrates that RanGTP regulation in the spindle is not simply a switch, but rather generates effector gradients where importins α and β gradually tune the activities of spindle assembly factors.
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Affiliation(s)
| | - Mackenzie Emch
- Department of Biology, Indiana University, Bloomington, IN
| | | | - Serena Mahnoor
- Indiana University International Summer Undergraduate Research Program, Bloomington, IN
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20
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Huang YA, Hsu CH, Chiu HC, Hsi PY, Ho CT, Lo WL, Hwang E. Actin waves transport RanGTP to the neurite tip to regulate non-centrosomal microtubules in neurons. J Cell Sci 2020; 133:jcs241992. [PMID: 32253322 DOI: 10.1242/jcs.241992] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 03/17/2020] [Indexed: 12/18/2022] Open
Abstract
Microtubules (MTs) are the most abundant cytoskeleton in neurons, and control multiple facets of their development. While the MT-organizing center (MTOC) in mitotic cells is typically located at the centrosome, the MTOC in neurons switches to non-centrosomal sites. A handful of cellular components have been shown to promote non-centrosomal MT (ncMT) formation in neurons, yet the regulation mechanism remains unknown. Here, we demonstrate that the small GTPase Ran is a key regulator of ncMTs in neurons. Using an optogenetic tool that enables light-induced local production of RanGTP, we demonstrate that RanGTP promotes ncMT plus-end growth along the neurite. Additionally, we discovered that actin waves drive the anterograde transport of RanGTP. Pharmacological disruption of actin waves abolishes the enrichment of RanGTP and reduces growing ncMT plus-ends at the neurite tip. These observations identify a novel regulation mechanism for ncMTs and pinpoint an indirect connection between the actin and MT cytoskeletons in neurons.
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Affiliation(s)
- Yung-An Huang
- Department of Biological Science and Technology, National Chiao Tung University, Hsinchu, Taiwan 30068
| | - Chih-Hsuan Hsu
- Institute of Molecular Medicine and Bioengineering, National Chiao Tung University, Hsinchu, Taiwan 30068
| | - Ho-Chieh Chiu
- Institute of Molecular Medicine and Bioengineering, National Chiao Tung University, Hsinchu, Taiwan 30068
| | - Pei-Yu Hsi
- Institute of Molecular Medicine and Bioengineering, National Chiao Tung University, Hsinchu, Taiwan 30068
| | - Chris T Ho
- Institute of Molecular Medicine and Bioengineering, National Chiao Tung University, Hsinchu, Taiwan 30068
| | - Wei-Lun Lo
- Department of Biological Science and Technology, National Chiao Tung University, Hsinchu, Taiwan 30068
| | - Eric Hwang
- Department of Biological Science and Technology, National Chiao Tung University, Hsinchu, Taiwan 30068
- Institute of Molecular Medicine and Bioengineering, National Chiao Tung University, Hsinchu, Taiwan 30068
- Institute of Bioinformatics and Systems Biology, National Chiao Tung University, Hsinchu, Taiwan 30068
- Center for Intelligent Drug Systems and Smart Bio-devices (IDS2B), National Chiao Tung University, Hsinchu, Taiwan 30068
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21
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Andrews PGP, Popadiuk C, Belbin TJ, Kao KR. Augmentation of Myc-Dependent Mitotic Gene Expression by the Pygopus2 Chromatin Effector. Cell Rep 2019; 23:1516-1529. [PMID: 29719262 DOI: 10.1016/j.celrep.2018.04.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Revised: 09/14/2017] [Accepted: 04/03/2018] [Indexed: 12/19/2022] Open
Abstract
Mitotic segregation of chromosomes requires precise coordination of many factors, yet evidence is lacking as to how genes encoding these elements are transcriptionally controlled. Here, we found that the Pygopus (Pygo)2 chromatin effector is indispensable for expression of the MYC-dependent genes that regulate cancer cell division. Depletion of Pygo2 arrested SKOV-3 cells at metaphase, which resulted from the failure of chromosomes to capture spindle microtubules, a critical step for chromosomal biorientation and segregation. This observation was consistent with global chromatin association findings in HeLa S3 cells, revealing the enrichment of Pygo2 and MYC at promoters of biorientation and segmentation genes, at which Pygo2 maintained histone H3K27 acetylation. Immunoprecipitation and proximity ligation assays demonstrated MYC and Pygo2 interacting in nuclei, corroborated in a heterologous MYC-driven prostate cancer model that was distinct from Wnt/β-catenin signaling. Our evidence supports a role for Pygo2 as an essential component of MYC oncogenic activity required for mitosis.
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Affiliation(s)
- Phillip G P Andrews
- Terry Fox Cancer Research Labs, Division of Biomedical Sciences, Faculty of Medicine, Memorial University, St. John's Campus, NL A1B 3V6, Canada
| | - Catherine Popadiuk
- Division of Gynecologic Oncology, Faculty of Medicine, Memorial University, St. John's Campus, NL A1B 3V6, Canada
| | - Thomas J Belbin
- Discipline of Oncology, Faculty of Medicine, Memorial University, St. John's Campus, NL A1B 3V6, Canada
| | - Kenneth R Kao
- Terry Fox Cancer Research Labs, Division of Biomedical Sciences, Faculty of Medicine, Memorial University, St. John's Campus, NL A1B 3V6, Canada; Discipline of Oncology, Faculty of Medicine, Memorial University, St. John's Campus, NL A1B 3V6, Canada.
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22
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Guo L, Mohd KS, Ren H, Xin G, Jiang Q, Clarke PR, Zhang C. Phosphorylation of importin-α1 by CDK1-cyclin B1 controls mitotic spindle assembly. J Cell Sci 2019; 132:jcs232314. [PMID: 31434716 PMCID: PMC6765185 DOI: 10.1242/jcs.232314] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 08/09/2019] [Indexed: 12/22/2022] Open
Abstract
Importin-α serves as an adaptor linking importin-β to proteins carrying a nuclear localization sequence (NLS). During interphase, this interaction enables nuclear protein import, while in mitosis it regulates spindle assembly factors (SAFs) and controls microtubule nucleation, stabilization and spindle function. Here, we show that human importin-α1 is regulated during the cell cycle and is phosphorylated at two sites (threonine 9 and serine 62) during mitosis by the major mitotic protein kinase CDK1-cyclin B. Mutational analysis indicates that the mitotic phosphorylation of importin-α1 inhibits its binding to importin-β and promotes the release of TPX2 and KIFC1, which are then targeted like importin-β to the spindle. Loss of importin-α1 or expression of a non-phosphorylated mutant of importin-α1 results in the formation of shortened spindles with reduced microtubule density and induces a prolonged metaphase, whereas phosphorylation-mimicking mutants are functional in mitosis. We propose that phosphorylation of importin-α1 is a general mechanism for the spatial and temporal control of mitotic spindle assembly by CDK1-cyclin B1 that acts through the release of SAFs such as TPX2 and KIFC1 from inhibitory complexes that restrict spindle assembly.
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Affiliation(s)
- Li Guo
- The MOE Key Laboratory of Cell Proliferation and Differentiation, College of Life Sciences, Peking University, Beijing 100871, China
| | - Khamsah Suryati Mohd
- School of Medicine, Jacqui Wood Cancer Centre, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, UK
| | - He Ren
- The MOE Key Laboratory of Cell Proliferation and Differentiation, College of Life Sciences, Peking University, Beijing 100871, China
| | - Guangwei Xin
- The MOE Key Laboratory of Cell Proliferation and Differentiation, College of Life Sciences, Peking University, Beijing 100871, China
| | - Qing Jiang
- The MOE Key Laboratory of Cell Proliferation and Differentiation, College of Life Sciences, Peking University, Beijing 100871, China
| | - Paul R Clarke
- School of Medicine, Jacqui Wood Cancer Centre, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, UK
- The University of Queensland Diamantina Institute, The University of Queensland, Woolloongabba, Brisbane, QLD 4102, Australia
| | - Chuanmao Zhang
- The MOE Key Laboratory of Cell Proliferation and Differentiation, College of Life Sciences, Peking University, Beijing 100871, China
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23
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Namgoong S, Kim NH. Meiotic spindle formation in mammalian oocytes: implications for human infertility. Biol Reprod 2019; 98:153-161. [PMID: 29342242 DOI: 10.1093/biolre/iox145] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Accepted: 12/27/2017] [Indexed: 12/12/2022] Open
Abstract
In the final stage of oogenesis, mammalian oocytes generate a meiotic spindle and undergo chromosome segregation to yield an egg that is ready for fertilization. Herein, we describe the recent advances in understanding the mechanisms controlling formation of the meiotic spindle in metaphase I (MI) and metaphase II (MII) in mammalian oocytes, and focus on the differences between mouse and human oocytes. Unlike mitotic cells, mammalian oocytes lack typical centrosomes that consist of two centrioles and the surrounding pericentriolar matrix proteins, which serve as microtubule-organizing centers (MTOCs) in most somatic cells. Instead, oocytes rely on different mechanisms for the formation of microtubules in MI spindles. Two different mechanisms have been described for MI spindle formation in mammalian oocytes. Chromosome-mediated microtubule formation, including RAN-mediated spindle formation and chromosomal passenger complex-mediated spindle elongation, controls the growth of microtubules from chromatin, while acentriolar MTOC-mediated microtubule formation contributes to spindle formation. Mouse oocytes utilize both chromatin- and MTOC-mediated pathways for microtubule formation. The existence of both pathways may provide a fail-safe mechanism to ensure high fidelity of chromosome segregation during meiosis. Unlike mouse oocytes, human oocytes considered unsuitable for clinical in vitro fertilization procedures, lack MTOCs; this may explain why meiosis in human oocytes is often error-prone. Understanding the mechanisms of MI/MII spindle formation, spindle assembly checkpoint, and chromosome segregation, in mammalian oocytes, will provide valuable insights into the molecular mechanisms of human infertility.
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Affiliation(s)
| | - Nam-Hyung Kim
- Department of Animal Science, Chungbuk National University, Cheong-Ju, Chungbuk, Republic of Korea
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24
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Liang HX, Liu HW. Inducible Expression of Ran1 and Its GDP- and GTP-Bound Mimetic Mutants Leads to Defects in Amitosis and Cytokinesis with Abnormal Cytoplasmic Microtubule Assembly. Mol Biol 2019. [DOI: 10.1134/s0026893319030105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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25
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Haggag YA, Matchett KB, Falconer RA, Isreb M, Jones J, Faheem A, McCarron P, El-Tanani M. Novel Ran-RCC1 Inhibitory Peptide-Loaded Nanoparticles Have Anti-Cancer Efficacy In Vitro and In Vivo. Cancers (Basel) 2019; 11:cancers11020222. [PMID: 30769871 PMCID: PMC6406988 DOI: 10.3390/cancers11020222] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Revised: 01/31/2019] [Accepted: 02/11/2019] [Indexed: 12/12/2022] Open
Abstract
The delivery of anticancer agents to their subcellular sites of action is a significant challenge for effective cancer therapy. Peptides, which are integral to several oncogenic pathways, have significant potential to be utilised as cancer therapeutics due to their selectivity, high potency and lack of normal cell toxicity. Novel Ras protein-Regulator of chromosome condensation 1 (Ran-RCC1) inhibitory peptides designed to interact with Ran, a novel therapeutic target in breast cancer, were delivered by entrapment into polyethylene glycol-poly (lactic-co-glycolic acid) PEG-PLGA polymeric nanoparticles (NPs). A modified double emulsion solvent evaporation technique was used to optimise the physicochemical properties of these peptide-loaded biodegradable NPs. The anti-cancer activity of peptide-loaded NPs was studied in vitro using Ran-expressing metastatic breast (MDA-MB-231) and lung cancer (A549) cell lines, and in vivo using Solid Ehrlich Carcinoma-bearing mice. The anti-metastatic activity of peptide-loaded NPs was investigated using migration, invasion and colony formation assays in vitro. A PEG-PLGA-nanoparticle encapsulating N-terminal peptide showed a pronounced antitumor and anti-metastatic action in lung and breast cancer cells in vitro and caused a significant reduction of tumor volume and associated tumor growth inhibition of breast cancer model in vivo. These findings suggest that the novel inhibitory peptides encapsulated into PEGylated PLGA NPs are delivered effectively to interact and deactivate Ran. This novel Ran-targeting peptide construct shows significant potential for therapy of breast cancer and other cancers mediated by Ran overexpression.
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Affiliation(s)
- Yusuf A Haggag
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Tanta, Tanta 31111, Egypt.
- School of Pharmacy and Pharmaceutical Sciences, Saad Centre for Pharmacy and Diabetes, Ulster University, Cromore Road, Coleraine, Co. Londonderry BT52 1SA, UK.
| | - Kyle B Matchett
- Northern Ireland Centre for Stratified Medicine, School of Biomedical Sciences, C-TRIC, Altnagelvin Hospital Campus, Ulster University, Glenshane Road, Derry/Londonderry BT47 6SB, Northern Ireland, UK.
| | - Robert A Falconer
- Institute of Cancer Therapeutics, Faculty of Life Sciences, University of Bradford, Bradford BD7 1DP, UK.
| | - Mohammad Isreb
- School of Pharmacy and Clinical Sciences, University of Bradford, Bradford BD7 1DP, UK.
| | - Jason Jones
- Institute of Cancer Therapeutics, Faculty of Life Sciences, University of Bradford, Bradford BD7 1DP, UK.
| | - Ahmed Faheem
- Department of Pharmacy, Health and Well-being, University of Sunderland, Sunderland SR1 3SD, UK.
| | - Paul McCarron
- School of Pharmacy and Pharmaceutical Sciences, Saad Centre for Pharmacy and Diabetes, Ulster University, Cromore Road, Coleraine, Co. Londonderry BT52 1SA, UK.
| | - Mohamed El-Tanani
- Institute of Cancer Therapeutics, Faculty of Life Sciences, University of Bradford, Bradford BD7 1DP, UK.
- Imhotep Diagnostics and Therapeutics, Europa Tool House, Springbank, Industrial Estate, Dunmurry BT17 0QL, Northern Ireland, UK.
- School of Chemistry and Biosciences, University of Bradford, Bradford BD7 1DP, UK.
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26
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Yang J, Guo Y, Lu C, Zhang R, Wang Y, Luo L, Zhang Y, Chu CH, Wang KJ, Obbad S, Yan W, Li X. Inhibition of Karyopherin beta 1 suppresses prostate cancer growth. Oncogene 2019; 38:4700-4714. [PMID: 30742095 PMCID: PMC6565446 DOI: 10.1038/s41388-019-0745-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 12/10/2018] [Accepted: 01/26/2019] [Indexed: 12/19/2022]
Abstract
Prostate cancer (PCa) initiation and progression requires activation of numerous oncogenic signaling pathways. Nuclear-cytoplasmic transport of oncogenic factors is mediated by Karyopherin proteins during cell transformation. However, the role of nuclear transporter proteins in PCa progression has not been well defined. Here, we report that the KPNB1, a key member of Karyopherin beta subunits, is highly expressed in advanced prostate cancers. Further study showed that targeting KPNB1 suppressed the proliferation of prostate cancer cells. The knockdown of KPNB1 reduced nuclear translocation of c-Myc, the expression of downstream cell cycle modulators, and phosphorylation of regulator of chromatin condensation 1 (RCC1), a key protein for spindle assembly during mitosis. Meanwhile, CHIP assay demonstrated the binding of c-Myc to KPNB1 promoter region, which indicated a positive feedback regulation of KPNB1 expression mediated by the c-Myc. In addition, NF-κB subunit p50 translocation to nuclei was blocked by KPNB1 inhibition, which led to an increase in apoptosis and a decrease in tumor sphere formation of PCa cells. Furthermore, subcutaneous xenograft tumor models with a stable knockdown of KPNB1 in C42B PCa cells validated that the inhibition of KPNB1 could suppress the growth of prostate tumor in vivo. Moreover, the intravenously administration of importazole, a specific inhibitor for KPNB1, effectively reduced PCa tumor size and weight in mice inoculated with PC3 PCa cells. In summary, our data established the functional link between KPNB1 and PCa prone c-Myc, NF-kB, and cell cycle modulators. More importantly, inhibition of KPNB1 could be a new therapeutic target for PCa treatment.
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Affiliation(s)
- Jian Yang
- Department of Basic Science and Craniofacial Biology, New York University College of Dentistry, New York, NY, 10010, USA
| | - Yuqi Guo
- Department of Basic Science and Craniofacial Biology, New York University College of Dentistry, New York, NY, 10010, USA
| | - Cuijie Lu
- Department of Basic Science and Craniofacial Biology, New York University College of Dentistry, New York, NY, 10010, USA
| | - Ruohan Zhang
- Department of Basic Science and Craniofacial Biology, New York University College of Dentistry, New York, NY, 10010, USA
| | - Yaoyu Wang
- Department of Basic Science and Craniofacial Biology, New York University College of Dentistry, New York, NY, 10010, USA
| | - Liang Luo
- Department of Basic Science and Craniofacial Biology, New York University College of Dentistry, New York, NY, 10010, USA
| | - Yanli Zhang
- Department of Basic Science and Craniofacial Biology, New York University College of Dentistry, New York, NY, 10010, USA
| | - Catherine H Chu
- Department of Basic Science and Craniofacial Biology, New York University College of Dentistry, New York, NY, 10010, USA
| | - Katherine J Wang
- Department of Basic Science and Craniofacial Biology, New York University College of Dentistry, New York, NY, 10010, USA
| | - Sabrine Obbad
- Department of Basic Science and Craniofacial Biology, New York University College of Dentistry, New York, NY, 10010, USA
| | - Wenbo Yan
- Department of Basic Science and Craniofacial Biology, New York University College of Dentistry, New York, NY, 10010, USA
| | - Xin Li
- Department of Basic Science and Craniofacial Biology, New York University College of Dentistry, New York, NY, 10010, USA. .,Department of Urology, New York University Langone Medical Center, New York, NY, 10016, USA. .,Perlmutter Cancer Institute, New York University Langone Medical Center, New York, NY, 10016, USA.
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27
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Liang H, Xu J, Wang W. Ran1 is essential for parental macronuclear import of apoptosis-inducing factor and programmed nuclear death in Tetrahymena thermophila. FEBS J 2019; 286:913-929. [PMID: 30663224 DOI: 10.1111/febs.14761] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 11/30/2018] [Accepted: 01/17/2019] [Indexed: 01/30/2023]
Abstract
During programmed nuclear death (PND), apoptosis-inducing factor (AIF) translocates from mitochondria to the parental macronucleus (MAC) in Tetrahymena thermophila. In the degenerating parental MAC, AIF induces chromatin condensation and large-scale DNA fragmentation in a caspase-independent manner. However, the regulation of AIF nuclear translocation and molecular mechanism of PND are less clear. In this study, we demonstrated that the asymmetric distribution of nuclear GDP-bound Ran1-mimetic mutant Ran1T25N and cytoplasmic GTP-bound Ran1-mimetic mutant Ran1Q70L exists across the parental macronuclear-cytoplasmic barrier during PND. Knockdown of RAN1 led to defects in PND progression and failure of parental macronuclear accumulation of AIF. Moreover, AIF parental macronuclear import occurred in Ran1T25N mutants, while it was inhibited in Ran1Q70L mutants. Importantly, artificial accumulation of AIF in the parental MAC rescued PND progression defects in RAN1 knockdown mutants. These data suggest that Ran1 is essential for parental macronuclear import of AIF and PND in T. thermophila.
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Affiliation(s)
- Haixia Liang
- Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Shanxi University, Taiyuan, China.,MicroNano System Research Center, Key Laboratory of Advanced Transducers and Intelligent Control System of Ministry of Education and Shanxi Province, College of Information & Computer Engineering, Taiyuan University of Technology, China
| | - Jing Xu
- Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Shanxi University, Taiyuan, China
| | - Wei Wang
- Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Shanxi University, Taiyuan, China
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28
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Riahi A, Radmanesh H, Schürmann P, Bogdanova N, Geffers R, Meddeb R, Kharrat M, Dörk T. Exome sequencing and case-control analyses identify RCC1 as a candidate breast cancer susceptibility gene. Int J Cancer 2018; 142:2512-2517. [PMID: 29363114 DOI: 10.1002/ijc.31273] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 11/29/2017] [Accepted: 01/05/2018] [Indexed: 01/03/2023]
Abstract
Breast cancer is a genetic disease but the known genes explain a minority of cases. To elucidate the molecular basis of breast cancer in the Tunisian population, we performed exome sequencing on six BRCA1/BRCA2 mutation-negative patients with familial breast cancer and identified a novel frameshift mutation in RCC1, encoding the Regulator of Chromosome Condensation 1. Subsequent genotyping detected the 19-bp deletion in additional 5 out of 153 (3%) breast cancer patients but in none of 400 female controls (p = 0.0015). The deletion was enriched in patients with a positive family history (5%, p = 0.0009) and co-segregated with breast cancer in the initial pedigree. The mutant allele was lost in 4/6 breast tumors from mutation carriers which may be consistent with the hypothesis that RCC1 dysfunction provides a selective disadvantage at the stage of tumor progression. In summary, we propose RCC1 as a likely breast cancer susceptibility gene in the Tunisian population.
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Affiliation(s)
- Aouatef Riahi
- Gynaecology Research Unit, Hannover Medical School, Hannover, Germany.,Laboratoire Génétique Humaine, Faculté de Médecine de Tunis, University Tunis El Manar, Tunis, Tunisia
| | - Hoda Radmanesh
- Gynaecology Research Unit, Hannover Medical School, Hannover, Germany.,Medical Genetic Research Center (MGRC), School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Peter Schürmann
- Gynaecology Research Unit, Hannover Medical School, Hannover, Germany
| | - Natalia Bogdanova
- Gynaecology Research Unit, Hannover Medical School, Hannover, Germany.,Hannover Medical School, Radiation Oncology Research Unit, Hannover, Germany
| | - Robert Geffers
- Genome Analytics Unit, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Rym Meddeb
- Laboratoire Génétique Humaine, Faculté de Médecine de Tunis, University Tunis El Manar, Tunis, Tunisia.,Department of Hereditary and Congenital Disorders, Charles Nicolle Hospital, Tunis, Tunisia
| | - Maher Kharrat
- Laboratoire Génétique Humaine, Faculté de Médecine de Tunis, University Tunis El Manar, Tunis, Tunisia
| | - Thilo Dörk
- Gynaecology Research Unit, Hannover Medical School, Hannover, Germany
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29
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Aoki K, Niki H. Release of condensin from mitotic chromosomes requires the Ran-GTP gradient in the reorganized nucleus. Biol Open 2017; 6:1614-1628. [PMID: 28954740 PMCID: PMC5703609 DOI: 10.1242/bio.027193] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
After mitosis, nuclear reorganization occurs together with decondensation of mitotic chromosomes and reformation of the nuclear envelope, thereby restoring the Ran-GTP gradient between the nucleus and cytoplasm. The Ran-GTP gradient is dependent on Pim1/RCC1. Interestingly, a defect in Pim1/RCC1 in Schizosaccharomyces pombe causes postmitotic condensation of chromatin, namely hypercondensation, suggesting a relationship between the Ran-GTP gradient and chromosome decondensation. However, how Ran-GTP interacts with chromosome decondensation is unresolved. To examine this interaction, we used Schizosaccharomyces japonicus, which is known to undergo partial breakdown of the nuclear membrane during mitosis. We found that Pim1/RCC1 was localized on nuclear pores, but this localization failed in a temperature-sensitive mutant of Pim1/RCC1. The mutant cells exhibited hypercondensed chromatin after mitosis due to prolonged association of condensin on the chromosomes. Conceivably, a condensin-dephosphorylation defect might cause hypercondensed chromatin, since chromosomal localization of condensin is dependent on phosphorylation by cyclin-dependent kinase (CDK). Indeed, CDK-phospho-mimic mutation of condensin alone caused untimely condensin localization, resulting in hypercondensed chromatin. Together, these results suggest that dephosphorylation of CDK sites of condensin might require the Ran-GTP gradient produced by nuclear pore-localized Pim1/RCC1. Summary: A mutant of Pim1/RCC1 caused hypercondensed chromatin after mitosis due to prolonged association of condensin on chromosomes, suggesting that dephosphorylation of CDK sites of condensin might require Ran-GTP after mitosis.
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Affiliation(s)
- Keita Aoki
- Microbial Genetics Laboratory, Genetic Strains Research Center, National Institute of Genetics, 1111 Yata, Mishima, Shizuoka 411-8540, Japan .,Department of Genetics, SOKENDAI, National Institute of Genetics, 1111 Yata, Mishima, Shizuoka 411-8540, Japan
| | - Hironori Niki
- Microbial Genetics Laboratory, Genetic Strains Research Center, National Institute of Genetics, 1111 Yata, Mishima, Shizuoka 411-8540, Japan.,Department of Genetics, SOKENDAI, National Institute of Genetics, 1111 Yata, Mishima, Shizuoka 411-8540, Japan
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30
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Koyama M, Sasaki T, Sasaki N, Matsuura Y. Crystal structure of human WBSCR16, an RCC1-like protein in mitochondria. Protein Sci 2017; 26:1870-1877. [PMID: 28608466 DOI: 10.1002/pro.3210] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Revised: 06/05/2017] [Accepted: 06/05/2017] [Indexed: 11/09/2022]
Abstract
WBSCR16 (Williams-Beuren Syndrome Chromosomal Region 16) gene is located in a large deletion region of Williams-Beuren syndrome (WBS), which is a neurodevelopmental disorder. Although the relationship between WBSCR16 and WBS remains unclear, it has been reported that WBSCR16 is a member of a functional module that regulates mitochondrial 16S rRNA abundance and intra-mitochondrial translation. WBSCR16 has RCC1 (Regulator of Chromosome Condensation 1)-like amino acid sequence repeats but the function of WBSCR16 appears to be different from that of other RCC1 superfamily members. Here, we demonstrate that WBSCR16 localizes to mitochondria in HeLa cells, and report the crystal structure of WBSCR16 determined to 2.0 Å resolution using multi-wavelength anomalous diffraction. WBSCR16 adopts the seven-bladed β-propeller fold characteristic of RCC1-like proteins. A comparison of the WBSCR16 structure with that of RCC1 and other RCC1-like proteins reveals that, although many of the residues buried in the core of the β-propeller are highly conserved, the surface residues are poorly conserved and conformationally divergent.
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Affiliation(s)
- Masako Koyama
- Division of Biological Science, Nagoya University, Furo-cho, Chikusa-ku, Japan
| | - Taeko Sasaki
- Division of Biological Science, Nagoya University, Furo-cho, Chikusa-ku, Japan
| | - Narie Sasaki
- Division of Biological Science, Nagoya University, Furo-cho, Chikusa-ku, Japan
| | - Yoshiyuki Matsuura
- Division of Biological Science, Nagoya University, Furo-cho, Chikusa-ku, Japan.,Structural Biology Research Center, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Japan
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31
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Zheng H, Wu H, Pan X, Jin W, Li X. Aberrant Meiotic Modulation Partially Contributes to the Lower Germination Rate of Pollen Grains in Maize (Zea mays L.) Under Low Nitrogen Supply. PLANT & CELL PHYSIOLOGY 2017; 58:342-353. [PMID: 28007967 DOI: 10.1093/pcp/pcw195] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2016] [Accepted: 11/08/2016] [Indexed: 06/06/2023]
Abstract
Pollen germination is an essential step towards successful pollination during maize reproduction. How low niutrogen (N) affects pollen germination remains an interesting biological question to be addressed. We found that only low N resulted in a significantly lower germination rate of pollen grains after 4 weeks of low N, phosphorus or potassium treatment in maize production. Importantly, cytological analysis showed 7-fold more micronuclei in male meiocytes under the low N treatment than in the control, indicating that the lower germination rate of pollen grains was partially due to numerous chromosome loss events resulting from preceding meiosis. The appearance of 10 bivalents in the control and low N cells at diakinesis suggested that chromosome pairing and recombination in meiosis I was not affected by low N. Further gene expression analysis revealed dramatic down-regulation of Nuclear Division Cycle 80 (Ndc80) and Regulator of Chromosome Condensation 1 (Rcc1-1) expression and up-regulation of Cell Division Cycle 20 (Cdc20-1) expression, although no significant difference in the expression level of kinetochore foundation proteins Centromeric Histone H3 (Cenh3) and Centromere Protein C (Cenpc) and cohesion regulators Recombination 8 (Rec8) and Shugoshin (Sgo1) was observed. Aberrant modulation of three key meiotic regulators presumably resulted in a high likelihood of erroneous chromosome segregation, as testified by pronounced lagging chromosomes at anaphase I or cell cycle disruption at meiosis II. Thus, we proposed a cytogenetic mechanism whereby low N affects male meiosis and causes a higher chromosome loss frequency and eventually a lower germination rate of pollen grains in a staple crop plant.
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Affiliation(s)
- Hongyan Zheng
- Key Laboratory of Plant-Soil Interactions of the Ministry of Education, and Department of Plant Nutrition, China Agricultural University, Beijing, China
| | - Huamao Wu
- Key Laboratory of Plant-Soil Interactions of the Ministry of Education, and Department of Plant Nutrition, China Agricultural University, Beijing, China
| | - Xiaoying Pan
- Key Laboratory of Plant-Soil Interactions of the Ministry of Education, and Department of Plant Nutrition, China Agricultural University, Beijing, China
| | - Weiwei Jin
- The National Maize Center, and Department of Plant Genetics and Breeding, China Agricultural University, Beijing, China
| | - Xuexian Li
- Key Laboratory of Plant-Soil Interactions of the Ministry of Education, and Department of Plant Nutrition, China Agricultural University, Beijing, China
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32
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Dudka D, Meraldi P. Symmetry Does not Come for Free: Cellular Mechanisms to Achieve a Symmetric Cell Division. Results Probl Cell Differ 2017; 61:301-321. [PMID: 28409311 DOI: 10.1007/978-3-319-53150-2_14] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
During mitosis cells can divide symmetrically to proliferate or asymmetrically to generate tissue diversity. While the mechanisms that ensure asymmetric cell division have been extensively studied, it is often assumed that a symmetric cell division is the default outcome of mitosis. Recent studies, however, imply that the symmetric nature of cell division is actively controlled, as they reveal numerous mechanisms that ensure the formation of equal-sized daughter cells as cells progress through cell division. Here we review our current knowledge of these mechanisms and highlight possible key questions in the field.
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Affiliation(s)
- Damian Dudka
- Medical Faculty, Department of Physiology and Metabolism, University of Geneva, 1211, Geneva 4, Switzerland
| | - Patrick Meraldi
- Medical Faculty, Department of Physiology and Metabolism, University of Geneva, 1211, Geneva 4, Switzerland.
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33
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Teves SS, An L, Hansen AS, Xie L, Darzacq X, Tjian R. A dynamic mode of mitotic bookmarking by transcription factors. eLife 2016; 5. [PMID: 27855781 PMCID: PMC5156526 DOI: 10.7554/elife.22280] [Citation(s) in RCA: 181] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 11/16/2016] [Indexed: 12/27/2022] Open
Abstract
During mitosis, transcription is shut off, chromatin condenses, and most transcription factors (TFs) are reported to be excluded from chromosomes. How do daughter cells re-establish the original transcription program? Recent discoveries that a select set of TFs remain bound on mitotic chromosomes suggest a potential mechanism for maintaining transcriptional programs through the cell cycle termed mitotic bookmarking. Here we report instead that many TFs remain associated with chromosomes in mouse embryonic stem cells, and that the exclusion previously described is largely a fixation artifact. In particular, most TFs we tested are significantly enriched on mitotic chromosomes. Studies with Sox2 reveal that this mitotic interaction is more dynamic than in interphase and is facilitated by both DNA binding and nuclear import. Furthermore, this dynamic mode results from lack of transcriptional activation rather than decreased accessibility of underlying DNA sequences in mitosis. The nature of the cross-linking artifact prompts careful re-examination of the role of TFs in mitotic bookmarking. DOI:http://dx.doi.org/10.7554/eLife.22280.001 A kidney cell functions differently from a skin cell despite the fact that all the cells in one organism share the same DNA. This is because not all of the genes encoded within the DNA are active in the cells. Instead, cells can turn on just those genes that are specific to how that cell type works. One way that cells can regulate their genes is by using proteins called transcription factors that can bind to DNA to turn nearby genes on and off. When cells divide to form new cells, the DNA is condensed and gene activity is turned off. However, each dividing cell also has to ‘remember’ the program of genes that specifies its identity. After division, how do the cells know which genes to turn on and which ones to keep off? It was thought that the transcription factors attached to the DNA were all detached from it during cell division. Through studies in mouse embryonic stem cells, Teves et al. now show that this finding is largely an artifact of the methods used to study the process. In fact, many transcription factors still bind to and interact with DNA during cell division. This provides an efficient way for the newly formed cells to quickly reset to the pattern of gene activity appropriate for their cell type. Having found that many key transcription factors are still bound to DNA during cell division, the next challenge is to find out what role this binding plays in allowing cells to ‘remember’ their identity. DOI:http://dx.doi.org/10.7554/eLife.22280.002
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Affiliation(s)
- Sheila S Teves
- Department of Molecular and Cell Biology, University of California, Berkeley, United States
| | - Luye An
- Department of Molecular and Cell Biology, University of California, Berkeley, United States
| | - Anders S Hansen
- Department of Molecular and Cell Biology, University of California, Berkeley, United States.,CIRM Center of Excellence, University of California, Berkeley, Berkeley, United States
| | - Liangqi Xie
- Department of Molecular and Cell Biology, University of California, Berkeley, United States.,CIRM Center of Excellence, University of California, Berkeley, Berkeley, United States
| | - Xavier Darzacq
- Department of Molecular and Cell Biology, University of California, Berkeley, United States.,CIRM Center of Excellence, University of California, Berkeley, Berkeley, United States
| | - Robert Tjian
- Department of Molecular and Cell Biology, University of California, Berkeley, United States.,CIRM Center of Excellence, University of California, Berkeley, Berkeley, United States.,Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, United States
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34
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Vleugel M, Roth S, Groenendijk CF, Dogterom M. Reconstitution of Basic Mitotic Spindles in Spherical Emulsion Droplets. J Vis Exp 2016. [PMID: 27584979 DOI: 10.3791/54278] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Mitotic spindle assembly, positioning and orientation depend on the combined forces generated by microtubule dynamics, microtubule motor proteins and cross-linkers. Growing microtubules can generate pushing forces, while depolymerizing microtubules can convert the energy from microtubule shrinkage into pulling forces, when attached, for example, to cortical dynein or chromosomes. In addition, motor proteins and diffusible cross-linkers within the spindle contribute to spindle architecture by connecting and sliding anti-parallel microtubules. In vivo, it has proven difficult to unravel the relative contribution of individual players to the overall balance of forces. Here we present the methods that we recently developed in our efforts to reconstitute basic mitotic spindles bottom-up in vitro. Using microfluidic techniques, centrosomes and tubulin are encapsulated in water-in-oil emulsion droplets, leading to the formation of geometrically confined (double) microtubule asters. By additionally introducing cortically anchored dynein, plus-end directed microtubule motors and diffusible cross-linkers, this system is used to reconstitute spindle-like structures. The methods presented here provide a starting point for reconstitution of more complete mitotic spindles, allowing for a detailed study of the contribution of each individual component, and for obtaining an integrated quantitative view of the force-balance within the mitotic spindle.
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Affiliation(s)
- Mathijs Vleugel
- Department of Bionanoscience, Delft University of Technology
| | - Sophie Roth
- Department of Bionanoscience, Delft University of Technology
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35
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Abstract
Concentration gradients of soluble proteins are believed to be responsible for control of morphogenesis of subcellular systems, but the mechanisms that generate the spatial organization of these subcellular gradients remain poorly understood. Here, we use a newly developed multipoint fluorescence fluctuation spectroscopy technique to study the ras-related nuclear protein (Ran) pathway, which forms soluble gradients around chromosomes in mitosis and is thought to spatially regulate microtubule behaviors during spindle assembly. We found that the distribution of components of the Ran pathway that influence microtubule behaviors is determined by their interactions with microtubules, resulting in microtubule nucleators being localized by the microtubules whose formation they stimulate. Modeling and perturbation experiments show that this feedback makes the length of the spindle insensitive to the length scale of the Ran gradient, allows the spindle to assemble outside the peak of the Ran gradient, and explains the scaling of the spindle with cell size. Such feedback between soluble signaling pathways and the mechanics of the cytoskeleton may be a general feature of subcellular organization.
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36
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Furuta M, Hori T, Fukagawa T. Chromatin binding of RCC1 during mitosis is important for its nuclear localization in interphase. Mol Biol Cell 2015; 27:371-81. [PMID: 26564799 PMCID: PMC4713138 DOI: 10.1091/mbc.e15-07-0497] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 11/06/2015] [Indexed: 12/24/2022] Open
Abstract
RCC1, a guanine nucleotide exchange factor of the small GTPase Ran, plays various roles throughout the cell cycle. However, the functions of RCC1 in biological processes in vivo are still unclear. In particular, although RCC1 has multifunctional domains, the biological significance of each domain is unclear. To examine each domain of RCC1, we established an RCC1 conditional knockout chicken DT40 cell line and introduced various RCC1 mutants into the knockout cells. We found that nuclear reformation did not occur properly in RCC1-deficient cells and examined whether specific RCC1 mutants could rescue this phenotype. Surprisingly, we found that neither the nuclear localization signal nor the chromatin-binding domain of RCC1 is essential for its function. However, codisruption of these domains resulted in defective nuclear reformation, which was rescued by artificial nuclear localization of RCC1. Our data indicate that chromatin association of RCC1 during mitosis is crucial for its proper nuclear localization in the next interphase. Moreover, proper nuclear localization of RCC1 in interphase is essential for its function through its nucleotide exchange activity.
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Affiliation(s)
- Maiko Furuta
- Department of Molecular Genetics, National Institute of Genetics, and Graduate University for Advanced Studies (SOKENDAI), Mishima, Shizuoka 411-8540, Japan
| | - Tetsuya Hori
- Department of Molecular Genetics, National Institute of Genetics, and Graduate University for Advanced Studies (SOKENDAI), Mishima, Shizuoka 411-8540, Japan Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan
| | - Tatsuo Fukagawa
- Department of Molecular Genetics, National Institute of Genetics, and Graduate University for Advanced Studies (SOKENDAI), Mishima, Shizuoka 411-8540, Japan Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan
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37
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Abstract
The mitotic spindle is the macromolecular machine utilized to accurately segregate chromosomes in cells. How this self-organized structure assembles is a key aspect of understanding spindle morphogenesis. In the present review, we focus on understanding mechanisms of spindle self-assembly and address how subcellular signalling gradients, such as Ran-GTP and Aurora B, contribute to spindle organization and function.
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Stanne T, Narayanan MS, Ridewood S, Ling A, Witmer K, Kushwaha M, Wiesler S, Wickstead B, Wood J, Rudenko G. Identification of the ISWI Chromatin Remodeling Complex of the Early Branching Eukaryote Trypanosoma brucei. J Biol Chem 2015; 290:26954-26967. [PMID: 26378228 PMCID: PMC4646403 DOI: 10.1074/jbc.m115.679019] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Indexed: 12/25/2022] Open
Abstract
ISWI chromatin remodelers are highly conserved in eukaryotes and are important for the assembly and spacing of nucleosomes, thereby controlling transcription initiation and elongation. ISWI is typically associated with different subunits, forming specialized complexes with discrete functions. In the unicellular parasite Trypanosoma brucei, which causes African sleeping sickness, TbISWI down-regulates RNA polymerase I (Pol I)-transcribed variant surface glycoprotein (VSG) gene expression sites (ESs), which are monoallelically expressed. Here, we use tandem affinity purification to determine the interacting partners of TbISWI. We identify three proteins that do not show significant homology with known ISWI-associated partners. Surprisingly, one of these is nucleoplasmin-like protein (NLP), which we had previously shown to play a role in ES control. In addition, we identify two novel ISWI partners, regulator of chromosome condensation 1-like protein (RCCP) and phenylalanine/tyrosine-rich protein (FYRP), both containing protein motifs typically found on chromatin proteins. Knockdown of RCCP or FYRP in bloodstream form T. brucei results in derepression of silent variant surface glycoprotein ESs, as had previously been shown for TbISWI and NLP. All four proteins are expressed and interact with each other in both major life cycle stages and show similar distributions at Pol I-transcribed loci. They are also found at Pol II strand switch regions as determined with ChIP. ISWI, NLP, RCCP, and FYRP therefore appear to form a single major ISWI complex in T. brucei (TbIC). This reduced complexity of ISWI regulation and the presence of novel ISWI partners highlights the early divergence of trypanosomes in evolution.
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Affiliation(s)
- Tara Stanne
- Division of Cell and Molecular Biology, Department of Life Sciences, Sir Alexander Fleming Building, Imperial College London, South Kensington, London SW7 2AZ, United Kingdom and
| | - Mani Shankar Narayanan
- Division of Cell and Molecular Biology, Department of Life Sciences, Sir Alexander Fleming Building, Imperial College London, South Kensington, London SW7 2AZ, United Kingdom and
| | - Sophie Ridewood
- Division of Cell and Molecular Biology, Department of Life Sciences, Sir Alexander Fleming Building, Imperial College London, South Kensington, London SW7 2AZ, United Kingdom and
| | - Alexandra Ling
- Division of Cell and Molecular Biology, Department of Life Sciences, Sir Alexander Fleming Building, Imperial College London, South Kensington, London SW7 2AZ, United Kingdom and
| | - Kathrin Witmer
- Division of Cell and Molecular Biology, Department of Life Sciences, Sir Alexander Fleming Building, Imperial College London, South Kensington, London SW7 2AZ, United Kingdom and
| | - Manish Kushwaha
- Division of Cell and Molecular Biology, Department of Life Sciences, Sir Alexander Fleming Building, Imperial College London, South Kensington, London SW7 2AZ, United Kingdom and
| | - Simone Wiesler
- Division of Cell and Molecular Biology, Department of Life Sciences, Sir Alexander Fleming Building, Imperial College London, South Kensington, London SW7 2AZ, United Kingdom and
| | - Bill Wickstead
- the School of Life Sciences, University of Nottingham, Nottingham NG7 2UH, United Kingdom
| | - Jennifer Wood
- Division of Cell and Molecular Biology, Department of Life Sciences, Sir Alexander Fleming Building, Imperial College London, South Kensington, London SW7 2AZ, United Kingdom and
| | - Gloria Rudenko
- Division of Cell and Molecular Biology, Department of Life Sciences, Sir Alexander Fleming Building, Imperial College London, South Kensington, London SW7 2AZ, United Kingdom and.
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Abstract
Chromosomes are not only carriers of the genetic material, but also actively regulate the assembly of complex intracellular architectures. During mitosis, chromosome-induced microtubule polymerisation ensures spindle assembly in cells without centrosomes and plays a supportive role in centrosome-containing cells. Chromosomal signals also mediate post-mitotic nuclear envelope (NE) re-formation. Recent studies using novel approaches to manipulate histones in oocytes, where functions can be analysed in the absence of transcription, have established that nucleosomes, but not DNA alone, mediate the chromosomal regulation of spindle assembly and NE formation. Both processes require the generation of RanGTP by RCC1 recruited to nucleosomes but nucleosomes also acquire cell cycle stage specific regulators, Aurora B in mitosis and ELYS, the initiator of nuclear pore complex assembly, at mitotic exit. Here, we review the mechanisms by which nucleosomes control assembly and functions of the spindle and the NE, and discuss their implications for genome maintenance.
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Affiliation(s)
- Christian Zierhut
- Laboratory of Chromosome and Cell Biology, Rockefeller University, New York, NY, USA
| | - Hironori Funabiki
- Laboratory of Chromosome and Cell Biology, Rockefeller University, New York, NY, USA
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Papini D, Langemeyer L, Abad MA, Kerr A, Samejima I, Eyers PA, Jeyaprakash AA, Higgins JMG, Barr FA, Earnshaw WC. TD-60 links RalA GTPase function to the CPC in mitosis. Nat Commun 2015; 6:7678. [PMID: 26158537 PMCID: PMC4510650 DOI: 10.1038/ncomms8678] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2014] [Accepted: 05/29/2015] [Indexed: 12/26/2022] Open
Abstract
TD-60 (also known as RCC2) is a highly conserved protein that structurally resembles the Ran guanine exchange factor (GEF) RCC1, but has not previously been shown to have GEF activity. TD-60 has a typical chromosomal passenger complex (CPC) distribution in mitotic cells, but associates with integrin complexes and is involved in cell motility during interphase. Here we show that TD-60 exhibits GEF activity, in vitro and in cells, for the small GTPase RalA. TD-60 or RalA depletion causes spindle abnormalities in prometaphase associated with abnormal centromeric accumulation of CPC components. TD-60 and RalA apparently work together to contribute to the regulation of kinetochore-microtubule interactions in early mitosis. Importantly, several mitotic phenotypes caused by TD-60 depletion are reverted by the expression of a GTP-locked mutant, RalA (Q72L). The demonstration that a small GTPase participates in the regulation of the CPC reveals a level of mitotic regulation not suspected in previous studies.
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Affiliation(s)
- Diana Papini
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, Michael Swann Building, Kings Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
- Institute for Cell and Molecular Biosciences (ICaMB), Newcastle University, Medical School, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Lars Langemeyer
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
| | - Maria A. Abad
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, Michael Swann Building, Kings Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Alastair Kerr
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, Michael Swann Building, Kings Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Itaru Samejima
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, Michael Swann Building, Kings Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Patrick A. Eyers
- Department of Biochemistry, Institute of Integrative Biology, University of Liverpool, Crown St, Liverpool L69 7ZB, UK
| | - A. Arockia Jeyaprakash
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, Michael Swann Building, Kings Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Jonathan M. G. Higgins
- Institute for Cell and Molecular Biosciences (ICaMB), Newcastle University, Medical School, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Francis A. Barr
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
| | - William C. Earnshaw
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, Michael Swann Building, Kings Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
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41
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Maiato H, Logarinho E. Mitotic spindle multipolarity without centrosome amplification. Nat Cell Biol 2014; 16:386-94. [DOI: 10.1038/ncb2958] [Citation(s) in RCA: 110] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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42
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Bernis C, Swift-Taylor B, Nord M, Carmona S, Chook YM, Forbes DJ. Transportin acts to regulate mitotic assembly events by target binding rather than Ran sequestration. Mol Biol Cell 2014; 25:992-1009. [PMID: 24478460 PMCID: PMC3967982 DOI: 10.1091/mbc.e13-08-0506] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Transportin-specific molecular tools are used to show that the mitotic cell contains importin β and transportin “global positioning system” pathways that are mechanistically parallel. Transportin works to control where the spindle, nuclear membrane, and nuclear pores are formed by directly affecting assembly factor function. The nuclear import receptors importin β and transportin play a different role in mitosis: both act phenotypically as spatial regulators to ensure that mitotic spindle, nuclear membrane, and nuclear pore assembly occur exclusively around chromatin. Importin β is known to act by repressing assembly factors in regions distant from chromatin, whereas RanGTP produced on chromatin frees factors from importin β for localized assembly. The mechanism of transportin regulation was unknown. Diametrically opposed models for transportin action are as follows: 1) indirect action by RanGTP sequestration, thus down-regulating release of assembly factors from importin β, and 2) direct action by transportin binding and inhibiting assembly factors. Experiments in Xenopus assembly extracts with M9M, a superaffinity nuclear localization sequence that displaces cargoes bound by transportin, or TLB, a mutant transportin that can bind cargo and RanGTP simultaneously, support direct inhibition. Consistently, simple addition of M9M to mitotic cytosol induces microtubule aster assembly. ELYS and the nucleoporin 107–160 complex, components of mitotic kinetochores and nuclear pores, are blocked from binding to kinetochores in vitro by transportin, a block reversible by M9M. In vivo, 30% of M9M-transfected cells have spindle/cytokinesis defects. We conclude that the cell contains importin β and transportin “global positioning system”or “GPS” pathways that are mechanistically parallel.
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Affiliation(s)
- Cyril Bernis
- Section of Cell and Developmental Biology, Division of Biological Sciences 0347, University of California-San Diego, La Jolla, CA 92093-0347 Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9041
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43
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Ran GTPase in nuclear envelope formation and cancer metastasis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 773:323-51. [PMID: 24563355 DOI: 10.1007/978-1-4899-8032-8_15] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Ran is a small ras-related GTPase that controls the nucleocytoplasmic exchange of macromolecules across the nuclear envelope. It binds to chromatin early during nuclear formation and has important roles during the eukaryotic cell cycle, where it regulates mitotic spindle assembly, nuclear envelope formation and cell cycle checkpoint control. Like other GTPases, Ran relies on the cycling between GTP-bound and GDP-bound conformations to interact with effector proteins and regulate these processes. In nucleocytoplasmic transport, Ran shuttles across the nuclear envelope through nuclear pores. It is concentrated in the nucleus by an active import mechanism where it generates a high concentration of RanGTP by nucleotide exchange. It controls the assembly and disassembly of a range of complexes that are formed between Ran-binding proteins and cellular cargo to maintain rapid nuclear transport. Ran also has been identified as an essential protein in nuclear envelope formation in eukaryotes. This mechanism is dependent on importin-β, which regulates the assembly of further complexes important in this process, such as Nup107-Nup160. A strong body of evidence is emerging implicating Ran as a key protein in the metastatic progression of cancer. Ran is overexpressed in a range of tumors, such as breast and renal, and these perturbed levels are associated with local invasion, metastasis and reduced patient survival. Furthermore, tumors with oncogenic KRAS or PIK3CA mutations are addicted to Ran expression, which yields exciting future therapeutic opportunities.
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Wu Z, Jiang Q, Clarke PR, Zhang C. Phosphorylation of Crm1 by CDK1-cyclin-B promotes Ran-dependent mitotic spindle assembly. J Cell Sci 2013; 126:3417-28. [PMID: 23729730 DOI: 10.1242/jcs.126854] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Mitotic spindle assembly in animal cells is orchestrated by a chromosome-dependent pathway that directs microtubule stabilization. RanGTP generated at chromosomes releases spindle assembly factors from inhibitory complexes with importins, the nuclear transport factors that facilitate protein import into the nucleus during interphase. In addition, the nuclear export factor Crm1 has been proposed to act as a mitotic effector of RanGTP through the localized assembly of protein complexes on the mitotic spindle, notably at centrosomes and kinetochores. It has been unclear, however, how the functions of nuclear transport factors are controlled during mitosis. Here, we report that human Crm1 is phosphorylated at serine 391 in mitosis by CDK1-cyclin-B (i.e. the CDK1 and cyclin B complex). Expression of Crm1 with serine 391 mutated to either non-phosphorylated or phosphorylation-mimicking residues indicates that phosphorylation directs the localization of Crm1 to the mitotic spindle and facilitates spindle assembly, microtubule stabilization and chromosome alignment. We find that phosphorylation of Crm1 at serine 391 enhances its RanGTP-dependent interaction with RanGAP1-RanBP2 and promotes their recruitment to the mitotic spindle. These results show that phosphorylation of Crm1 controls its molecular interactions, localization and function during mitosis, uncovering a new mechanism for the control of mitotic spindle assembly by CDK1-cyclin-B. We propose that nuclear transport factors are controlled during mitosis through the selection of specific molecular interactions by protein phosphorylation.
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Affiliation(s)
- Zhige Wu
- The MOE Key Laboratory of Cell Proliferation and Differentiation and the State Key Laboratory of Bio-membrane and Membrane Bio-engineering, College of Life Sciences, Peking University, Beijing 100871, China
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45
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Martín-Gómez L, Villalba A, Carballal MJ, Abollo E. Identification of relevant cancer related-genes in the flat oyster Ostrea edulis affected by disseminated neoplasia. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2013; 15:159-174. [PMID: 22833317 DOI: 10.1007/s10126-012-9472-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2012] [Accepted: 06/30/2012] [Indexed: 06/01/2023]
Abstract
Disseminated neoplasia (DN), an oyster disease resembling leukaemia, has been reported in a number of species of marine bivalve molluscs. The disease is characterised by a proliferation of abnormal circulating cells of unknown origin resulting in the invasion of tissues and organs, frequently with a fatal end of the affected individuals. To obtain a more comprehensive view of bivalve cancer processes, suppressive subtracted hybridisation (SSH) and quantitative RT-PCR (q-PCR) approaches were combined to investigate changes in the transcriptome of Ostrea edulis haemolymph cells associated to DN. Two SSH libraries were constructed and 587 expressed sequence tags (ESTs) were sequenced, obtaining 329 ESTs which showed expression changes in neoplastic process. Transcription expression analyses (q-PCR) were done for a total of 24 genes that could be relevant in neoplastic process, including genes with role in the regulation of cell cycle, apoptosis or chromosomal defects. Most of those genes had not been reported in association with cancer in non-vertebrate organisms. The over-expression and under-expression of some of those genes in DN-affected oysters was in agreement with observations in vertebrate cancer. The results herein reported contribute to cancer understanding in bivalve molluscs.
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Affiliation(s)
- Laura Martín-Gómez
- Centro de Investigacións Mariñas, Consellería do Medio Rural e do Mar, Xunta de Galicia, Aptdo 13, 36620 Vilanova de Arousa, Spain.
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Pfaff KL, King RW. Determinants of human cyclin B1 association with mitotic chromosomes. PLoS One 2013; 8:e59169. [PMID: 23505570 PMCID: PMC3594322 DOI: 10.1371/journal.pone.0059169] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2012] [Accepted: 02/13/2013] [Indexed: 12/28/2022] Open
Abstract
Cyclin B1–CDK1 activity is essential for mitotic entry, but questions remain regarding how the activity of this kinase is spatially regulated. Previous studies showed that the cyclin B1 subunit localizes to several compartments of a mitotic cell, including the centrosomes, mitotic spindle, kinetochores and chromosomes via distinct sequence elements. Mitotic chromosome association occurs through the unstructured N-terminal domain of cyclin B1 and is independent of CDK1 binding. Here, we use live cell imaging of human cyclin B1 fused to GFP to precisely define the sequence elements within cyclin B1 that mediate its association with condensed mitotic chromosomes. We find that a short, evolutionarily conserved N-terminal motif is required for cyclin B1 to localize to mitotic chromosomes. We further reveal a role for arginine residues within and near the destruction box sequence in the chromosome association of cyclin B1. Additionally, our data suggest that sequences further downstream in cyclin B1, such as the cytoplasmic retention sequence and the cyclin box, may negatively modulate chromosome association. Because multiple basic residues are required for cyclin B1 association with mitotic chromosomes, electrostatic interactions with DNA may facilitate cyclin B1 localization to chromosomes.
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Affiliation(s)
- Kathleen L. Pfaff
- Harvard Medical School Department of Cell Biology, Boston, Massachusetts, United States of America
| | - Randall W. King
- Harvard Medical School Department of Cell Biology, Boston, Massachusetts, United States of America
- * E-mail:
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47
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Liang H, Xu J, Zhao D, Tian H, Yang X, Liang A, Wang W. Subcellular localization and role of Ran1 in Tetrahymena thermophila amitotic macronucleus. FEBS J 2012; 279:2520-33. [PMID: 22594798 DOI: 10.1111/j.1742-4658.2012.08634.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Amitosis, a direct method of cell division is common in ciliated protozoan, fungi and some animal and plant cells. During amitosis, intranuclear microtubules are reorganized into specified arrays which assist in separation of nucleus, despite lack of a bipolar spindle. However, the regulation of amitosis is not understood. Here, we focused on the localization and role of mitotic spindle assembly regulator: Ran GTPase (Ran1) in macronuclear amitosis in binucleated protozoan Tetrahymena thermophila. HA-tagged Ran1 was localized in the macronucleus throughout the cell cycle of Tetrahymena during vegetative growth, and the accessory factor binding domains of Ran1 contributed to its macronuclear localization. Incomplete somatic knockout of RAN1 resulted in aberrant intramacronuclear microtubule array formation, missegregation of macronuclear chromosomes and ultimately blocked macronuclei proliferation. When the Ran1 cycle was perturbed by overexpression of Ran1T25N (GDP-bound Ran1-mimetic) or Ran1Q70L (GTP-bound Ran1-mimetic), intramacronuclear microtubule assembly was inhibited or multi-micronucleate cells formed. These results suggest that Ran GTPase pathway is involved in assembly of a specialized intramacronuclear microtubule network and coordinates amitotic progression in Tetrahymena.
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Affiliation(s)
- Haixia Liang
- Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Biotechnology, Shanxi University, Taiyuan, China
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48
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Roscioli E, Di Francesco L, Bolognesi A, Giubettini M, Orlando S, Harel A, Schininà ME, Lavia P. Importin-β negatively regulates multiple aspects of mitosis including RANGAP1 recruitment to kinetochores. J Cell Biol 2012; 196:435-50. [PMID: 22331847 PMCID: PMC3283988 DOI: 10.1083/jcb.201109104] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2011] [Accepted: 01/18/2012] [Indexed: 12/23/2022] Open
Abstract
Importin-β is the main vector for interphase nuclear protein import and plays roles after nuclear envelope breakdown. Here we show that importin-β regulates multiple aspects of mitosis via distinct domains that interact with different classes of proteins in human cells. The C-terminal region (which binds importin-α) inhibits mitotic spindle pole formation. The central region (harboring nucleoporin-binding sites) regulates microtubule dynamic functions and interaction with kinetochores. Importin-β interacts through this region with NUP358/RANBP2, which in turn binds SUMO-conjugated RANGAP1 in nuclear pores. We show that this interaction continues after nuclear pore disassembly. Overexpression of importin-β, or of the nucleoporin-binding region, inhibited RANGAP1 recruitment to mitotic kinetochores, an event that is known to require microtubule attachment and the exportin CRM1. Co-expressing either importin-β-interacting RANBP2 fragments, or CRM1, restored RANGAP1 to kinetochores and rescued importin-β-dependent mitotic dynamic defects. These results reveal previously unrecognized importin-β functions at kinetochores exerted via RANBP2 and opposed by CRM1.
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Affiliation(s)
- Emanuele Roscioli
- Institute of Molecular Biology and Pathology, CNR National Research Council, 00185 Rome, Italy
| | - Laura Di Francesco
- Department of Biochemical Sciences, Sapienza University of Rome, 00185 Rome, Italy
| | - Alessio Bolognesi
- Institute of Molecular Biology and Pathology, CNR National Research Council, 00185 Rome, Italy
| | - Maria Giubettini
- Institute of Molecular Biology and Pathology, CNR National Research Council, 00185 Rome, Italy
| | - Serena Orlando
- Institute of Molecular Biology and Pathology, CNR National Research Council, 00185 Rome, Italy
| | - Amnon Harel
- Department of Biology, Technion-Israel Institute of Technology, Haifa 32000, Israel
| | | | - Patrizia Lavia
- Institute of Molecular Biology and Pathology, CNR National Research Council, 00185 Rome, Italy
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Specific Cooperation Between Imp-α2 and Imp-β/Ketel in Spindle Assembly During Drosophila Early Nuclear Divisions. G3-GENES GENOMES GENETICS 2012; 2:1-14. [PMID: 22384376 PMCID: PMC3276186 DOI: 10.1534/g3.111.001073] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2011] [Accepted: 10/14/2011] [Indexed: 12/22/2022]
Abstract
The multifunctional factors Imp-α and Imp-β are involved in nuclear protein import, mitotic spindle dynamics, and nuclear membrane formation. Furthermore, each of the three members of the Imp-α family exerts distinct tasks during development. In Drosophila melanogaster, the imp-α2 gene is critical during oogenesis for ring canal assembly; specific mutations, which allow oogenesis to proceed normally, were found to block early embryonic mitosis. Here, we show that imp-α2 and imp-β genetically interact during early embryonic development, and we characterize the pattern of defects affecting mitosis in embryos laid by heterozygous imp-α2(D14) and imp-β(KetRE34) females. Embryonic development is arrested in these embryos but is unaffected in combinations between imp-β(KetRE34) and null mutations in imp-α1 or imp-α3. Furthermore, the imp-α2(D14)/imp-β(KetRE34) interaction could only be rescued by an imp-α2 transgene, albeit not imp-α1 or imp-α3, showing the exclusive imp-α2 function with imp-β. Use of transgenes carrying modifications in the major Imp-α2 domains showed the critical requirement of the nuclear localization signal binding (NLSB) site in this process. In the mutant embryos, we found metaphase-arrested mitoses made of enlarged spindles, suggesting an unrestrained activity of factors promoting spindle assembly. In accordance with this, we found that Imp-β(KetRE34) and Imp-β(KetD) bind a high level of RanGTP/GDP, and a deletion decreasing RanGTP level suppresses the imp-β(KetRE34) phenotype. These data suggest that a fine balance among Imp-α2, Imp-β, RanGTP, and the NLS cargos is critical for mitotic progression during early embryonic development.
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50
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The site of RanGTP generation can act as an organizational cue for mitotic microtubules. Biol Cell 2011; 103:421-34. [PMID: 21692748 DOI: 10.1042/bc20100135] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
BACKGROUND INFORMATION RanGTP, which is generated on chromosomes during mitosis, is required for microtubule spindle assembly. Due to its restricted spatial generation within the cell it has been suggested that RanGTP acts as a spatial cue to organize site-specific spindle assembly within the cell. However, the absence of a detectable sharp gradient of RanGTP in somatic cells has led to suggestions that it may only act as a spatial cue in large cells and that it may operate as a general activator of the mitotic cytosol in somatic cells. RESULTS We report that ectopic generation of RanGTP at the plasma membrane stimulates the formation of organized arrays of microtubules at the plasma membrane. CONCLUSIONS These results suggest that the site of RanGTP generation in a mitotic somatic cell can generate critical spatial information that specifies where microtubules grow towards and where microtubules are organized. As RanGTP is normally generated on chromosomes, these results suggest that RanGTP may play an important role in specifying that spindle assembly occurs around chromosomes.
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