1
|
Almacellas E, Mauvezin C. Emerging roles of mitotic autophagy. J Cell Sci 2022; 135:275665. [PMID: 35686549 DOI: 10.1242/jcs.255802] [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: 01/18/2023] Open
Abstract
Lysosomes exert pleiotropic functions to maintain cellular homeostasis and degrade autophagy cargo. Despite the great advances that have boosted our understanding of autophagy and lysosomes in both physiology and pathology, their function in mitosis is still controversial. During mitosis, most organelles are reshaped or repurposed to allow the correct distribution of chromosomes. Mitotic entry is accompanied by a reduction in sites of autophagy initiation, supporting the idea of an inhibition of autophagy to protect the genetic material against harmful degradation. However, there is accumulating evidence revealing the requirement of selective autophagy and functional lysosomes for a faithful chromosome segregation. Degradation is the most-studied lysosomal activity, but recently described alternative functions that operate in mitosis highlight the lysosomes as guardians of mitotic progression. Because the involvement of autophagy in mitosis remains controversial, it is important to consider the specific contribution of signalling cascades, the functions of autophagic proteins and the multiple roles of lysosomes, as three entangled, but independent, factors controlling genomic stability. In this Review, we discuss the latest advances in this area and highlight the therapeutic potential of targeting autophagy for drug development.
Collapse
Affiliation(s)
- Eugenia Almacellas
- Molecular Cell Biology of Autophagy, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Caroline Mauvezin
- Department of Biomedicine, Faculty of Medicine, University of Barcelona c/ Casanova, 143 08036 Barcelona, Spain.,August Pi i Sunyer Biomedical Research Institute (IDIBAPS), c/ Rosselló, 149-153 08036 Barcelona, Spain
| |
Collapse
|
2
|
AGO2 localizes to cytokinetic protrusions in a p38-dependent manner and is needed for accurate cell division. Commun Biol 2021; 4:726. [PMID: 34117353 PMCID: PMC8196063 DOI: 10.1038/s42003-021-02130-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 02/22/2021] [Indexed: 02/06/2023] Open
Abstract
Argonaute 2 (AGO2) is an indispensable component of the RNA-induced silencing complex, operating at the translational or posttranscriptional level. It is compartmentalized into structures such as GW- and P-bodies, stress granules and adherens junctions as well as the midbody. Here we show using immunofluorescence, image and bioinformatic analysis and cytogenetics that AGO2 also resides in membrane protrusions such as open- and close-ended tubes. The latter are cytokinetic bridges where AGO2 colocalizes at the midbody arms with cytoskeletal components such as α-Τubulin and Aurora B, and various kinases. AGO2, phosphorylated on serine 387, is located together with Dicer at the midbody ring in a manner dependent on p38 MAPK activity. We further show that AGO2 is stress sensitive and important to ensure the proper chromosome segregation and cytokinetic fidelity. We suggest that AGO2 is part of a regulatory mechanism triggered by cytokinetic stress to generate the appropriate micro-environment for local transcript homeostasis. Pantazopoulou et al. find that AGO2 resides in open-ended tunneling nanotubes and close-ended cytokinetic bridges. At the latter location, AGO2 colocalizes with cell division components and the authors show that AGO2 depletion impairs cell division fidelity.
Collapse
|
3
|
Richards JS, Candelaria NR, Lanz RB. Polyploid giant cancer cells and ovarian cancer: new insights into mitotic regulators and polyploidy†. Biol Reprod 2021; 105:305-316. [PMID: 34037700 DOI: 10.1093/biolre/ioab102] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 05/12/2021] [Accepted: 05/22/2021] [Indexed: 12/20/2022] Open
Abstract
Current first-line treatment of patients with high-grade serous ovarian cancer (HGSOC) involves the use of cytotoxic drugs that frequently lead to recurrent tumors exhibiting increased resistance to the drugs and poor patient survival. Strong evidence is accumulating to show that HGSOC tumors and cell lines contain a subset of cells called polyploidy giant cancer cells (PGCCs) that act as stem-like, self-renewing cells. These PGCCs appear to play a key role in tumor progression by generating drug-resistant progeny produced, in part, as a consequence of utilizing a modified form of mitosis known as endoreplication. Thus, developing drugs to target PGCCs and endoreplication may be an important approach for reducing the appearance of drug-resistant progeny. In the review, we discuss newly identified regulatory factors that impact mitosis and which may be altered or repurposed during endoreplication in PGCCs. We also review recent papers showing that a single PGCC can give rise to tumors in vivo and spheroids in culture. To illustrate some of the specific features of PGCCs and factors that may impact their function and endoreplication compared to mitosis, we have included immunofluorescent images co-localizing p53 and specific mitotic regulatory, phosphoproteins in xenografts derived from commonly used HGSOC cell lines.
Collapse
Affiliation(s)
- JoAnne S Richards
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Nicholes R Candelaria
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Rainer B Lanz
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
| |
Collapse
|
4
|
Jiang YH, Wang HL, Peng J, Zhu Y, Zhang HG, Tang FQ, Jian Z, Xiao YB. Multinucleated polyploid cardiomyocytes undergo an enhanced adaptability to hypoxia via mitophagy. J Mol Cell Cardiol 2019; 138:115-135. [PMID: 31783035 DOI: 10.1016/j.yjmcc.2019.11.155] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 11/15/2019] [Accepted: 11/18/2019] [Indexed: 01/18/2023]
Abstract
AIMS There is a large subpopulation of multinucleated polyploid cardiomyocytes (M*Pc CMs) in the adult mammalian heart. However, the pathophysiological significance of increased M*Pc CMs in heart disease is poorly understood. We sought to determine the pathophysiological significance of increased M*Pc CMs during hypoxia adaptation. METHODS AND RESULTS A model of hypoxia-induced cardiomyocyte (CM) multinucleation and polyploidization was established and found to be associated with less apoptosis and less reactive oxygen species (ROS) production. Compared to mononucleated diploid CMs (1*2c CMs), tetraploid CMs (4c CMs) exhibited better mitochondria quality control via increased mitochondrial autophagy (mitophagy). RNA-seq revealed Prkaa2, the gene for AMPKα2, was the most obviously up-regulated autophagy-related gene. Knockdown of AMPKα2 increased apoptosis and ROS production and suppressed mitophagy in 4c CMs compared to 1*2c CMs. Rapamycin, an autophagy activator, alleviated the adverse effect of AMPKα2 knockdown. Furthermore, silencing PINK1 also increased apoptosis and ROS in 4c CMs and weakened the adaptive superiority of 4c CMs. Finally, AMPKα2-/- mutant mice exhibited exacerbation of apoptosis and ROS production via decreases in AMPKα2-mediated mitophagy in 4c CMs compared to 1*2c CMs during hypoxia. CONCLUSIONS Compared to 1*2c CMs, hypoxia-induced 4c CMs exhibited enhanced mitochondria quality control and less apoptosis via AMPKα2-mediated mitophagy. These results suggest that multinucleation and polyploidization allow CM to better adapt to stress via enhanced mitophagy. In addition, activation of AMPKα2 may be a promising target for myocardial hypoxia-related diseases.
Collapse
Affiliation(s)
- Yun-Han Jiang
- Department of Cardiovascular Surgery, Xinqiao Hospital, Army Medical University, Chongqing 400037, PR China
| | - Hai-Long Wang
- Department of Cardiovascular Surgery, Xinqiao Hospital, Army Medical University, Chongqing 400037, PR China
| | - Jin Peng
- Central Laboratory, Xinqiao Hospital, Army Medical University, Chongqing 400037, PR China
| | - Yu Zhu
- Department of Cardiovascular Surgery, Xinqiao Hospital, Army Medical University, Chongqing 400037, PR China
| | - Hua-Gang Zhang
- Health Company, No. 75310 Corps of Chinese People's Liberation Army, Wuhan 400037, PR China
| | - Fu-Qin Tang
- Department of Cardiovascular Surgery, Xinqiao Hospital, Army Medical University, Chongqing 400037, PR China
| | - Zhao Jian
- Department of Cardiovascular Surgery, Xinqiao Hospital, Army Medical University, Chongqing 400037, PR China.
| | - Ying-Bin Xiao
- Department of Cardiovascular Surgery, Xinqiao Hospital, Army Medical University, Chongqing 400037, PR China.
| |
Collapse
|
5
|
Wang S, Hwang EE, Guha R, O'Neill AF, Melong N, Veinotte CJ, Conway Saur A, Wuerthele K, Shen M, McKnight C, Alexe G, Lemieux ME, Wang A, Hughes E, Xu X, Boxer MB, Hall MD, Kung A, Berman JN, Davis MI, Stegmaier K, Crompton BD. High-throughput Chemical Screening Identifies Focal Adhesion Kinase and Aurora Kinase B Inhibition as a Synergistic Treatment Combination in Ewing Sarcoma. Clin Cancer Res 2019; 25:4552-4566. [PMID: 30979745 DOI: 10.1158/1078-0432.ccr-17-0375] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 12/18/2018] [Accepted: 04/09/2019] [Indexed: 12/27/2022]
Abstract
PURPOSE Ewing sarcoma is an aggressive solid tumor malignancy of childhood. Although current treatment regimens cure approximately 70% of patients with localized disease, they are ineffective for most patients with metastases or relapse. New treatment combinations are necessary for these patients. EXPERIMENTAL DESIGN Ewing sarcoma cells are dependent on focal adhesion kinase (FAK) for growth. To identify candidate treatment combinations for Ewing sarcoma, we performed a small-molecule library screen to identify compounds synergistic with FAK inhibitors in impairing Ewing cell growth. The activity of a top-scoring class of compounds was then validated across multiple Ewing cell lines in vitro and in multiple xenograft models of Ewing sarcoma. RESULTS Numerous Aurora kinase inhibitors scored as synergistic with FAK inhibition in this screen. We found that Aurora kinase B inhibitors were synergistic across a larger range of concentrations than Aurora kinase A inhibitors when combined with FAK inhibitors in multiple Ewing cell lines. The combination of AZD-1152, an Aurora kinase B-selective inhibitor, and PF-562271 or VS-4718, FAK-selective inhibitors, induced apoptosis in Ewing sarcoma cells at concentrations that had minimal effects on survival when cells were treated with either drug alone. We also found that the combination significantly impaired tumor progression in multiple xenograft models of Ewing sarcoma. CONCLUSIONS FAK and Aurora kinase B inhibitors synergistically impair Ewing sarcoma cell viability and significantly inhibit tumor progression. This study provides preclinical support for the consideration of a clinical trial testing the safety and efficacy of this combination for patients with Ewing sarcoma.
Collapse
Affiliation(s)
- Sarah Wang
- Dana-Farber/Boston Children's Cancer and Blood Disorders Center, Boston, Massachusetts
| | - Elizabeth E Hwang
- Dana-Farber/Boston Children's Cancer and Blood Disorders Center, Boston, Massachusetts
| | - Rajarshi Guha
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland
| | - Allison F O'Neill
- Dana-Farber/Boston Children's Cancer and Blood Disorders Center, Boston, Massachusetts
| | | | - Chansey J Veinotte
- IWK Health Centre, Halifax, Nova Scotia, Canada
- Dalhousie University, Halifax, Nova Scotia, Canada
| | - Amy Conway Saur
- Dana-Farber/Boston Children's Cancer and Blood Disorders Center, Boston, Massachusetts
| | - Kellsey Wuerthele
- Dana-Farber/Boston Children's Cancer and Blood Disorders Center, Boston, Massachusetts
| | - Min Shen
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland
| | - Crystal McKnight
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland
| | - Gabriela Alexe
- Dana-Farber/Boston Children's Cancer and Blood Disorders Center, Boston, Massachusetts
- Boston University Bioinformatics Graduate Program, Boston, Massachusetts
| | | | - Amy Wang
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland
| | - Emma Hughes
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland
| | - Xin Xu
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland
| | - Matthew B Boxer
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland
| | - Matthew D Hall
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland
| | - Andrew Kung
- Memorial Sloan Kettering Cancer Center, New York, New York
| | - Jason N Berman
- IWK Health Centre, Halifax, Nova Scotia, Canada
- Dalhousie University, Halifax, Nova Scotia, Canada
| | - Mindy I Davis
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland
| | - Kimberly Stegmaier
- Dana-Farber/Boston Children's Cancer and Blood Disorders Center, Boston, Massachusetts.
| | - Brian D Crompton
- Dana-Farber/Boston Children's Cancer and Blood Disorders Center, Boston, Massachusetts.
| |
Collapse
|
6
|
Rosin FCP, Teixeira MG, Pelissari C, Corrêa L. Resistance of oral cancer cells to 5‐ALA‐mediated photodynamic therapy. J Cell Biochem 2018; 119:3554-3562. [DOI: 10.1002/jcb.26541] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 12/05/2017] [Indexed: 01/14/2023]
Affiliation(s)
- Flávia Cristina P. Rosin
- Pathology DepartmentSchool of DentistryUniversity of São Paulo. Av Prof Lineu PrestesSão PauloBrazil
| | - Marina Gabriela Teixeira
- Pathology DepartmentSchool of DentistryUniversity of São Paulo. Av Prof Lineu PrestesSão PauloBrazil
| | - Cibele Pelissari
- Pathology DepartmentSchool of DentistryUniversity of São Paulo. Av Prof Lineu PrestesSão PauloBrazil
| | - Luciana Corrêa
- Pathology DepartmentSchool of DentistryUniversity of São Paulo. Av Prof Lineu PrestesSão PauloBrazil
| |
Collapse
|
7
|
Kinases Involved in Both Autophagy and Mitosis. Int J Mol Sci 2017; 18:ijms18091884. [PMID: 28858266 PMCID: PMC5618533 DOI: 10.3390/ijms18091884] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Revised: 08/25/2017] [Accepted: 08/25/2017] [Indexed: 12/23/2022] Open
Abstract
Both mitosis and autophagy are highly regulated dynamic cellular processes and involve various phosphorylation events catalysed by kinases, which play vital roles in almost all physiological and pathological conditions. Mitosis is a key event during the cell cycle, in which the cell divides into two daughter cells. Autophagy is a process in which the cell digests its own cellular contents. Although autophagy regulation has mainly been studied in asynchronous cells, increasing evidence indicates that autophagy is in fact tightly regulated in mitosis. Here in this review, we will discuss kinases that were originally identified to be involved in only one of either mitosis or autophagy, but were later found to participate in both processes, such as CDKs (cyclin-dependent kinases), Aurora kinases, PLK-1 (polo-like kinase 1), BUB1 (budding uninhibited by benzimidazoles 1), MAPKs (mitogen-activated protein kinases), mTORC1 (mechanistic target of rapamycin complex 1), AMPK (AMP-activated protein kinase), PI3K (phosphoinositide-3 kinase) and protein kinase B (AKT). By focusing on kinases involved in both autophagy and mitosis, we will get a more comprehensive understanding about the reciprocal regulation between the two key cellular events, which will also shed light on their related therapeutic investigations.
Collapse
|
8
|
Yu ZJ, Luo HH, Shang ZF, Guan H, Xiao BB, Liu XD, Wang Y, Huang B, Zhou PK. Stabilization of 4E-BP1 by PI3K kinase and its involvement in CHK2 phosphorylation in the cellular response to radiation. Int J Med Sci 2017; 14:452-461. [PMID: 28539821 PMCID: PMC5441037 DOI: 10.7150/ijms.18329] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2016] [Accepted: 03/01/2017] [Indexed: 11/16/2022] Open
Abstract
Objectives: 4E-BP1 is a family member of eIF4E binding proteins (4E-BPs) which act as the suppressors of cap-dependent translation of RNA via competitively associating with cap-bound eIF4E. RNA translation regulation is an important manner to control the cellular responses to a series of stress conditions such as ionizing radiation (IR)-induced DNA damage response and cell cycle controlling. This study aimed to determine the mechanism of 4E-BP1 stabilization and its potential downstream target(s) in the response to IR. Methods: PI3Ks kinase inhibitors were used to determine the signaling control of 4E-BP1 phosphorylation and protein stability. shRNA strategy was employed to silence the expression of 4E-BP1 in HeLa and HepG2 cells, and determine its effect on the irradiation-induced CHK2 phosphorylation. The protein degradation/stability was investigated by western blotting on the condition of blocking novel protein synthesis by cycloheximide (CHX). Results: The phosphorylation of 4E-BP1 at Thr37/46 was significantly increased in both HepG2 and HeLa cells by ionizing radiation. Depression of 4E-BP1 by shRNA strategy resulted in an incomplete G2 arrest at the early stage of 2 hours post-irradiation, as well as a higher accumulation of mitotic cells at 10 and 12 hours post-irradiation as compared to the control cells. Consistently, the CHK2 phosphorylation at Thr68 induced by IR was also attenuated by silencing 4E-BP1 expression. Both PI3K and DNA-PKcs kinase inhibitors significantly decreased the protein level of 4E-BP1, which was associated with the accelerated degradation mediated by ubiquitination-proteasome pathway. Conclusion: PI3K kinase activity is necessary for maintaining 4E-BP1 stability. Our results also suggest 4E-BP1 a novel biological role of regulating cell cycle G2 checkpoint in responding to IR stress in association with controlling CHK2 phosphorylation.
Collapse
Affiliation(s)
- Zi-Jian Yu
- Department of Hepatobiliary Surgery, the First Affiliated Hospital, University of South China, Hengyang, Hunan Province 421001, P.R. China
| | - Hui-Hui Luo
- Institute for Environmental Medicine and Radiation Health, the College of Public Health, University of South China, Hengyang, Hunan Province 421001, P.R. China.,Department of Radiation Toxicology and Oncology, Beijing Key Laboratory for Radiobiology (BKLRB), Beijing Institute of Radiation Medicine, 100850 Beijing, P.R. China
| | - Zeng-Fu Shang
- School of Radiation Medicine and Protection, Medical College of Soochow University, Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Suzhou, Jiangsu Province 215123, P.R. China
| | - Hua Guan
- Department of Radiation Toxicology and Oncology, Beijing Key Laboratory for Radiobiology (BKLRB), Beijing Institute of Radiation Medicine, 100850 Beijing, P.R. China
| | - Bei-Bei Xiao
- School of Radiation Medicine and Protection, Medical College of Soochow University, Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Suzhou, Jiangsu Province 215123, P.R. China
| | - Xiao-Dan Liu
- Department of Radiation Toxicology and Oncology, Beijing Key Laboratory for Radiobiology (BKLRB), Beijing Institute of Radiation Medicine, 100850 Beijing, P.R. China
| | - Yu Wang
- Department of Radiation Toxicology and Oncology, Beijing Key Laboratory for Radiobiology (BKLRB), Beijing Institute of Radiation Medicine, 100850 Beijing, P.R. China
| | - Bo Huang
- Institute for Environmental Medicine and Radiation Health, the College of Public Health, University of South China, Hengyang, Hunan Province 421001, P.R. China
| | - Ping-Kun Zhou
- Institute for Environmental Medicine and Radiation Health, the College of Public Health, University of South China, Hengyang, Hunan Province 421001, P.R. China.,Department of Radiation Toxicology and Oncology, Beijing Key Laboratory for Radiobiology (BKLRB), Beijing Institute of Radiation Medicine, 100850 Beijing, P.R. China
| |
Collapse
|
9
|
Le LTT, Couvet M, Favier B, Coll JL, Nguyen CH, Molla A. Discovery of benzo[e]pyridoindolones as kinase inhibitors that disrupt mitosis exit while erasing AMPK-Thr172 phosphorylation on the spindle. Oncotarget 2016; 6:22152-66. [PMID: 26247630 PMCID: PMC4673153 DOI: 10.18632/oncotarget.4158] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Accepted: 05/30/2015] [Indexed: 01/09/2023] Open
Abstract
Aurora kinases play an essential role in mitotic progression and are attractive targets in cancer therapy. The first generation of benzo[e]pyridoindole exhibited powerful aurora kinase inhibition but their low solubility limited further development. Grafting a pyperidine-ethoxy group gives rise to a hydrosoluble inhibitor: compound C5M.C5M could efficiently inhibit the proliferation of cells from different origins. C5M prevented cell cycling, induced a strong mitotic arrest then, cells became polyploid and finally died. C5M did not impair the spindle checkpoint, the separation of the sister chromatids and the transfer of aurora B on the mid-zone. C5M prevented histone H3 phosphorylation at mitotic entry and erased AMPK-Thr172 phosphorylation in late mitosis. With this unique profile of inhibition, C5M could be useful for understanding the role of phospho-Thr172-AMPK in abscission and the relationship between the chromosomal complex and the energy sensing machinery.C5M is a multikinase inhibitor with interesting preclinical characteristics: high hydro-solubility and a good stability in plasma. A single dose prevents the expansion of multicellular spheroids. C5M can safely be injected to mice and reduces significantly the development of xenograft. The next step will be to define the protocol of treatment and the cancer therapeutic field of this new anti-proliferative drug.
Collapse
Affiliation(s)
- Ly-Thuy-Tram Le
- INSERM UJF U823 Institut Albert Bonniot, Team 5, BP 170, Grenoble Cedex 9, France.,Department of Biotechnology, University of Sciences and Technology, DaNang, Vietnam
| | - Morgane Couvet
- INSERM UJF U823 Institut Albert Bonniot, Team 5, BP 170, Grenoble Cedex 9, France
| | - Bertrand Favier
- Université Joseph Fourier - Grenoble, Team GREPI, Etablissement Français du Sang, BP35, La Tronche France
| | - Jean-Luc Coll
- INSERM UJF U823 Institut Albert Bonniot, Team 5, BP 170, Grenoble Cedex 9, France
| | - Chi-Hung Nguyen
- Institut Curie, PSL Research University, UMR 9187 - U 1196 CNRS-Institut Curie, INSERM, Bat 110 Centre Universitaire, Orsay, France
| | - Annie Molla
- INSERM UJF U823 Institut Albert Bonniot, Team 5, BP 170, Grenoble Cedex 9, France
| |
Collapse
|
10
|
An Z, Tassa A, Thomas C, Zhong R, Xiao G, Fotedar R, Tu BP, Klionsky DJ, Levine B. Autophagy is required for G₁/G₀ quiescence in response to nitrogen starvation in Saccharomyces cerevisiae. Autophagy 2014; 10:1702-11. [PMID: 25126732 PMCID: PMC4198356 DOI: 10.4161/auto.32122] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
In response to starvation, cells undergo increased levels of autophagy and cell cycle arrest but the role of autophagy in starvation-induced cell cycle arrest is not fully understood. Here we show that autophagy genes regulate cell cycle arrest in the budding yeast Saccharomyces cerevisiae during nitrogen starvation. While exponentially growing wild-type yeasts preferentially arrest in G1/G0 in response to starvation, yeasts carrying null mutations in autophagy genes show a significantly higher percentage of cells in G2/M. In these autophagy-deficient yeast strains, starvation elicits physiological properties associated with quiescence, such as Snf1 activation, glycogen and trehalose accumulation as well as heat-shock resistance. However, while nutrient-starved wild-type yeasts finish the G2/M transition and arrest in G1/G0, autophagy-deficient yeasts arrest in telophase. Our results suggest that autophagy is crucial for mitotic exit during starvation and appropriate entry into a G1/G0 quiescent state.
Collapse
Affiliation(s)
- Zhenyi An
- Center for Autophagy Research; University of Texas Southwestern Medical Center; Dallas, TX USA; Department of Internal Medicine; University of Texas Southwestern Medical Center; Dallas, TX USA
| | - Amina Tassa
- Department of Internal Medicine; University of Texas Southwestern Medical Center; Dallas, TX USA
| | - Collin Thomas
- Department of Internal Medicine; University of Texas Southwestern Medical Center; Dallas, TX USA
| | - Rui Zhong
- Department of Clinical Sciences; University of Texas Southwestern Medical Center; Dallas, TX USA
| | - Guanghua Xiao
- Department of Clinical Sciences; University of Texas Southwestern Medical Center; Dallas, TX USA
| | - Rati Fotedar
- Sanford Burnham Medical Research Institute; La Jolla, CA USA
| | - Benjamin P Tu
- Department of Biochemistry; University of Texas Southwestern Medical Center; Dallas, TX USA
| | | | - Beth Levine
- Center for Autophagy Research; University of Texas Southwestern Medical Center; Dallas, TX USA; Department of Internal Medicine; University of Texas Southwestern Medical Center; Dallas, TX USA; Department of Microbiology; University of Texas Southwestern Medical Center; Dallas, TX USA; Howard Hughes Medical Institute; University of Texas Southwestern Medical Center; Dallas, TX USA
| |
Collapse
|
11
|
Workman JJ, Chen H, Laribee RN. Environmental signaling through the mechanistic target of rapamycin complex 1: mTORC1 goes nuclear. Cell Cycle 2014; 13:714-25. [PMID: 24526113 PMCID: PMC3979908 DOI: 10.4161/cc.28112] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Mechanistic target of rapamycin complex 1 (mTORC1) is a well-known regulator of cell growth and proliferation in response to environmental stimuli and stressors. To date, the majority of mTORC1 studies have focused on its function as a cytoplasmic effector of translation regulation. However, recent studies have identified additional, nuclear-specific roles for mTORC1 signaling related to transcription of the ribosomal DNA (rDNA) and ribosomal protein (RP) genes, mitotic cell cycle control, and the regulation of epigenetic processes. As this area of study is still in its infancy, the purpose of this review to highlight these significant findings and discuss the relevance of nuclear mTORC1 signaling dysregulation as it pertains to health and disease.
Collapse
Affiliation(s)
- Jason J Workman
- Department of Pathology and Laboratory Medicine and Center for Cancer Research; University of Tennessee Health Science Center; Memphis, TN USA
| | - Hongfeng Chen
- Department of Pathology and Laboratory Medicine and Center for Cancer Research; University of Tennessee Health Science Center; Memphis, TN USA
| | - R Nicholas Laribee
- Department of Pathology and Laboratory Medicine and Center for Cancer Research; University of Tennessee Health Science Center; Memphis, TN USA
| |
Collapse
|
12
|
Cuyàs E, Corominas-Faja B, Joven J, Menendez JA. Cell cycle regulation by the nutrient-sensing mammalian target of rapamycin (mTOR) pathway. Methods Mol Biol 2014; 1170:113-44. [PMID: 24906312 DOI: 10.1007/978-1-4939-0888-2_7] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Cell division involves a series of ordered and controlled events that lead to cell proliferation. Cell cycle progression implies not only demanding amounts of cell mass, protein, lipid, and nucleic acid content but also a favorable energy state. The mammalian target of rapamycin (mTOR), in response to the energy state, nutrient status, and growth factor stimulation of cells, plays a pivotal role in the coordination of cell growth and the cell cycle. Here, we review how the nutrient-sensing mTOR-signaling cascade molecularly integrates nutritional and mitogenic/anti-apoptotic cues to accurately coordinate cell growth and cell cycle. First, we briefly outline the structure, functions, and regulation of the mTOR complexes (mTORC1 and mTORC2). Second, we concisely evaluate the best known ability of mTOR to control G1-phase progression. Third, we discuss in detail the recent evidence that indicates a new genome stability caretaker function of mTOR based on the specific ability of phosphorylated forms of several mTOR-signaling components (AMPK, raptor, TSC, mTOR, and S6K1), which spatially and temporally associate with essential mitotic regulators at the mitotic spindle and at the cytokinetic cleavage furrow.
Collapse
Affiliation(s)
- Elisabet Cuyàs
- Metabolism & Cancer Group, Translational Research Laboratory, Catalan Institute of Oncology, Girona (ICO-Girona), Hospital Dr. Josep Trueta de Girona, Ctra. França s/n, E-17007, Girona, Catalonia, Spain
| | | | | | | |
Collapse
|
13
|
Kogasaka Y, Hoshino Y, Hiradate Y, Tanemura K, Sato E. Distribution and association of mTOR with its cofactors, raptor and rictor, in cumulus cells and oocytes during meiotic maturation in mice. Mol Reprod Dev 2013; 80:334-48. [DOI: 10.1002/mrd.22166] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Accepted: 02/12/2013] [Indexed: 01/26/2023]
|
14
|
Trakala M, Fernández-Miranda G, Pérez de Castro I, Heeschen C, Malumbres M. Aurora B prevents delayed DNA replication and premature mitotic exit by repressing p21(Cip1). Cell Cycle 2013; 12:1030-41. [PMID: 23428904 DOI: 10.4161/cc.24004] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Aurora kinase B is a critical component of the chromosomal passenger complex, which is involved in the regulation of microtubule-kinetochore attachments and cytokinesis. By using conditional knockout cells and chemical inhibition, we show here that inactivation of Aurora B results in delayed G(1)/S transition and premature mitotic exit. Aurora B deficiency results in delayed DNA replication in cultured fibroblasts as well as liver cells after hepatectomy. This is accompanied by increased transcription of the cell cycle inhibitor p21 (Cip1). Lack of Aurora B does not prevent mitotic entry but results in a premature exit from prometaphase in the presence of increased p21(Cip1)-Cdk1 inactive complexes. Aurora B-null cells display reduced degradation of cyclin B1, suggesting the presence of phenomenon known as adaptation to the mitotic checkpoint, previously described in yeast. Elimination of p21(Cip1) rescues Cdk1 activity and prevents premature mitotic exit in Aurora B-deficient cells. These results suggest that Aurora B represses p21(Cip1), preventing delayed DNA replication, Cdk inhibition and premature mitotic exit. The upregulation of p21(Cip1) observed after inhibition of Aurora B may have important implications in cell cycle progression, tetraploidy, senescence or cancer therapy.
Collapse
Affiliation(s)
- Marianna Trakala
- Cell Division and Cancer Group, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | | | | | | | | |
Collapse
|
15
|
Mallampalli RK, Glasser JR, Coon TA, Chen BB. Calmodulin protects Aurora B on the midbody to regulate the fidelity of cytokinesis. Cell Cycle 2013; 12:663-73. [PMID: 23370391 DOI: 10.4161/cc.23586] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Aurora B kinase is an integral regulator of cytokinesis as it stabilizes the intercellular canal within the midbody to ensure proper chromosomal segregation during cell division. Here we identified an E3 ligase subunit, F box protein FBXL2, that by recognizing a calmodulin binding signature within Aurora B, ubiquitinates and removes the kinase from the midbody. Calmodulin, by competing with the F box protein for access to the calmodulin binding signature, protected Aurora B from FBXL2. Calmodulin co-localized with Aurora B on the midbody, preserved Aurora B levels in cells, and stabilized intercellular canals during delayed abscission. Genetic or pharmaceutical depletion of endogenous calmodulin significantly reduced Aurora B protein levels at the midbody resulting in tetraploidy and multi-spindle formation. The calmodulin inhibitor, calmidazolium, reduced Aurora B protein levels resulting in tetraploidy, mitotic arrest, and apoptosis of tumorigenic cells and profoundly inhibiting tumor formation in athymic nude mice. These observations indicate molecular interplay between Aurora B and calmodulin in telophase and suggest that calmodulin acts as a checkpoint sensor for chromosomal segregation errors during mitosis.
Collapse
Affiliation(s)
- Rama K Mallampalli
- Department of Medicine, The University of Pittsburgh, Pittsburgh, PA, USA
| | | | | | | |
Collapse
|