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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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2
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Thomas A, Meraldi P. Centrosome age breaks spindle size symmetry even in cells thought to divide symmetrically. J Cell Biol 2024; 223:e202311153. [PMID: 39012627 PMCID: PMC11252449 DOI: 10.1083/jcb.202311153] [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: 11/27/2023] [Revised: 03/14/2024] [Accepted: 05/03/2024] [Indexed: 07/17/2024] Open
Abstract
Centrosomes are the main microtubule-organizing centers in animal cells. Due to the semiconservative nature of centrosome duplication, the two centrosomes differ in age. In asymmetric stem cell divisions, centrosome age can induce an asymmetry in half-spindle lengths. However, whether centrosome age affects the symmetry of the two half-spindles in tissue culture cells thought to divide symmetrically is unknown. Here, we show that in human epithelial and fibroblastic cell lines centrosome age imposes a mild spindle asymmetry that leads to asymmetric cell daughter sizes. At the mechanistic level, we show that this asymmetry depends on a cenexin-bound pool of the mitotic kinase Plk1, which favors the preferential accumulation on old centrosomes of the microtubule nucleation-organizing proteins pericentrin, γ-tubulin, and Cdk5Rap2, and microtubule regulators TPX2 and ch-TOG. Consistently, we find that old centrosomes have a higher microtubule nucleation capacity. We postulate that centrosome age breaks spindle size symmetry via microtubule nucleation even in cells thought to divide symmetrically.
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Affiliation(s)
- Alexandre Thomas
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
- Translational Research Centre in Onco-hematology, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Patrick Meraldi
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
- Translational Research Centre in Onco-hematology, Faculty of Medicine, University of Geneva, Geneva, Switzerland
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3
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Yao Z, Chen J, Wang Y, Cao L. Bioinformatics analysis and validation of HAUS6 as a key prognostic gene in squamous cell carcinoma of the tongue. Arch Oral Biol 2024; 164:106000. [PMID: 38759391 DOI: 10.1016/j.archoralbio.2024.106000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 05/01/2024] [Accepted: 05/07/2024] [Indexed: 05/19/2024]
Abstract
OBJECTIVE To explore the expression of HAUS6 in squamous cell carcinoma of the tongue (TSCC) and its relationship with the clinicopathological features of patients, and to further provide new ideas and therapeutic targets for curing TSCC. DESIGN The Cancer Genome Atlas (TCGA) database was used to screen for differentially expressed genes (DEGs) between TSCC and normal tissues and survival analysis. DEGs of HAUS6 were screened and analyzed for GO, KEGG and GSEA enrichment. Exploring the correlation of HAUS6 with immune cell infiltration and immune checkpoint-related genes. The expression of HAUS6 in tumor and paraneoplastic tissues was confirmed by immunohistochemistry and Western Blot. RESULTS Analysis of the TCGA database results showed that expression of HAUS6 mRNA was significantly enhanced and correlated with overall survival (OS, p < 0.05) in TSCC. HAUS6 expression correlated with the level of immune cell infiltration and immune checkpoint-related genes. Immunohistochemistry and Western Blot confirmed that the expression level of HAUS6 protein was significantly higher in tumor tissues than in paraneoplastic tissues, and that tumor size and hypo-differentiation were higher in the HAUS6 high expression group than in the low expression group in TSCC (p < 0.05). CONCLUSIONS In conclusion, these analyses suggest that HAUS6 can act as an independent predictor of prognosis (p < 0.05) and high HAUS6 expression is strongly associated with poor prognosis.
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Affiliation(s)
- Zhuoyue Yao
- Department of Pathology, The First Affiliated Hospital of Anhui Medical University, No 218 Jixi Road, Hefei 230022, Anhui, China
| | - Jing Chen
- Pathology Teaching and Research Laboratory, Anhui Medical University, No 81 Meishan Road, Hefei 230032, Anhui, China
| | - Yue Wang
- Pathology Teaching and Research Laboratory, Anhui Medical University, No 81 Meishan Road, Hefei 230032, Anhui, China
| | - Liyu Cao
- Department of Pathology, The First Affiliated Hospital of Anhui Medical University, No 218 Jixi Road, Hefei 230022, Anhui, China; Pathology Teaching and Research Laboratory, Anhui Medical University, No 81 Meishan Road, Hefei 230032, Anhui, China.
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4
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Liu S, Yu Y, Xu J, Wang Y, Li D. Single-cell and bulk RNA-sequencing reveals mitosis-involved gene HAUS1 is a promising indicator for predicting prognosis and immune responses in prostate adenocarcinoma (PRAD). Cell Biol Int 2024; 48:1169-1184. [PMID: 38818762 DOI: 10.1002/cbin.12191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2023] [Revised: 04/13/2024] [Accepted: 05/04/2024] [Indexed: 06/01/2024]
Abstract
It was imperative to identify latent biomarkers pertinent to malignancies, given the pivotal role targeted molecular therapies play in tumor treatment investigations. This study aimed to assess the validity of HAUS1 as an indicator for survival prognosis and immune responses in prostate adenocarcinoma (PRAD) via single-cell and bulk RNA-sequencing. Related data on HAUS1 expression in PRAD were obtained from online databases, followed by comprehensive analyses to delineate its associations with survival prognosis, implicated pathways, and immune responses. Besides, the expression pattern of HAUS1 in PRAD was also verified in vitro, by using qRT-PCR, Western blot analysis, and immunohistochemistry. We found HAUS1 was downregulated in PRAD compared with normal tissues, as verified in vitro by qRT-PCR, Western blot, and immunohistochemistry (p < 0.05). Single-cell RNA-sequencing analysis indicated that HAUS1 had relatively higher expressions in B cells, Mono/Macro cells, and Endothelial cells compared with other cell types. Cox regression analysis revealed HAUS1 could serve as an independent indicator for the overall survival prognosis of PRAD (p < 0.05). Spearman correlation analyses revealed HAUS1 was closely related to the tumor microenvironment, immune cell infiltration levels, immune checkpoints, and immune cell pathways (p < 0.05). Furthermore, HAUS1 expression was found to be closely related to the immunotherapeutic response of patients receiving clinical intervention (p < 0.05). Collectively, our findings underscored the significant role of HAUS1 in PRAD prognosis and immune response, thereby presenting a novel and promising avenue for investigating the clinical utility of immunotherapy in PRAD.
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Affiliation(s)
- Shiwei Liu
- Department of Urology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Urology, Fudan University Shanghai Cancer Center, Shanghai, China
| | - Yang Yu
- Department of Urology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jie Xu
- Nursing Department, Wujiang Fifth People's Hospital, Suzhou, China
| | - Yi Wang
- Department of Urology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Urology, Affiliated Hospital of Nantong University, Nantong, Jiangsu Province, China
| | - Deng Li
- Department of Urology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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5
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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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6
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Zhang Y, Sung HH, Ziegler AB, Wu YC, Viais R, Sánchez-Huertas C, Kilo L, Agircan FG, Cheng YJ, Mouri K, Uemura T, Lüders J, Chien CT, Tavosanis G. Augmin complex activity finetunes dendrite morphology through non-centrosomal microtubule nucleation in vivo. J Cell Sci 2024; 137:jcs261512. [PMID: 38587100 PMCID: PMC11128282 DOI: 10.1242/jcs.261512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Accepted: 04/03/2024] [Indexed: 04/09/2024] Open
Abstract
During development, neurons achieve a stereotyped neuron type-specific morphology, which relies on dynamic support by microtubules (MTs). An important player is the augmin complex (hereafter augmin), which binds to existing MT filaments and recruits the γ-tubulin ring complex (γ-TuRC), to form branched MTs. In cultured neurons, augmin is important for neurite formation. However, little is known about the role of augmin during neurite formation in vivo. Here, we have revisited the role of mammalian augmin in culture and then turned towards the class four Drosophila dendritic arborization (c4da) neurons. We show that MT density is maintained through augmin in cooperation with the γ-TuRC in vivo. Mutant c4da neurons show a reduction of newly emerging higher-order dendritic branches and in turn also a reduced number of their characteristic space-filling higher-order branchlets. Taken together, our data reveal a cooperative function for augmin with the γ-TuRC in forming enough MTs needed for the appropriate differentiation of morphologically complex dendrites in vivo.
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Affiliation(s)
- Yun Zhang
- German Center for Neurodegenerative Diseases (DZNE), Dynamics of Neuronal Circuits Group, Venusberg Campus 1 Building 99, 53127 Bonn, Germany
| | - Hsin-Ho Sung
- Institute of Molecular Biology, Academia Sinica, 11529 Taipei, Taiwan
| | - Anna B. Ziegler
- German Center for Neurodegenerative Diseases (DZNE), Dynamics of Neuronal Circuits Group, Venusberg Campus 1 Building 99, 53127 Bonn, Germany
| | - Ying-Chieh Wu
- Institute of Molecular Biology, Academia Sinica, 11529 Taipei, Taiwan
| | - Ricardo Viais
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Carlos Sánchez-Huertas
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Lukas Kilo
- German Center for Neurodegenerative Diseases (DZNE), Dynamics of Neuronal Circuits Group, Venusberg Campus 1 Building 99, 53127 Bonn, Germany
| | - Fikret Gürkan Agircan
- German Center for Neurodegenerative Diseases (DZNE), Dynamics of Neuronal Circuits Group, Venusberg Campus 1 Building 99, 53127 Bonn, Germany
| | - Ying-Ju Cheng
- Institute of Molecular Biology, Academia Sinica, 11529 Taipei, Taiwan
| | - Kousuke Mouri
- Graduate School of Biostudies, Kyoto University, Kyoto 606-8501, Japan
| | - Tadashi Uemura
- Graduate School of Biostudies, Kyoto University, Kyoto 606-8501, Japan
- Center for Living Systems Information Science, Kyoto University
| | - Jens Lüders
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Cheng-Ting Chien
- Institute of Molecular Biology, Academia Sinica, 11529 Taipei, Taiwan
| | - Gaia Tavosanis
- German Center for Neurodegenerative Diseases (DZNE), Dynamics of Neuronal Circuits Group, Venusberg Campus 1 Building 99, 53127 Bonn, Germany
- LIMES Institute, University of Bonn, 53115 Bonn, Germany
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7
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Frese AN, Mariossi A, Levine MS, Wühr M. Quantitative proteome dynamics across embryogenesis in a model chordate. iScience 2024; 27:109355. [PMID: 38510129 PMCID: PMC10951915 DOI: 10.1016/j.isci.2024.109355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 12/11/2023] [Accepted: 02/23/2024] [Indexed: 03/22/2024] Open
Abstract
The evolution of gene expression programs underlying the development of vertebrates remains poorly characterized. Here, we present a comprehensive proteome atlas of the model chordate Ciona, covering eight developmental stages and ∼7,000 translated genes, accompanied by a multi-omics analysis of co-evolution with the vertebrate Xenopus. Quantitative proteome comparisons argue against the widely held hourglass model, based solely on transcriptomic profiles, whereby peak conservation is observed during mid-developmental stages. Our analysis reveals maximal divergence at these stages, particularly gastrulation and neurulation. Together, our work provides a valuable resource for evaluating conservation and divergence of multi-omics profiles underlying the diversification of vertebrates.
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Affiliation(s)
- Alexander N. Frese
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
| | - Andrea Mariossi
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
| | - Michael S. Levine
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
| | - Martin Wühr
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
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8
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Ge J, Yue Y, Nie HY, Liu KG, Li H, Lin HG, Zhang T, Yan HF, Sun HW, Yang JW, Zhou JL, Cui Y. Simulated microgravity altered the gene expression profiles and inhibited the proliferation of Kupffer cells in the early phase by downregulating LMO2 and EZH2. LIFE SCIENCES IN SPACE RESEARCH 2024; 40:21-34. [PMID: 38245345 DOI: 10.1016/j.lssr.2023.11.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Revised: 09/30/2023] [Accepted: 11/08/2023] [Indexed: 01/22/2024]
Abstract
Microgravity is a primary challenge that need to overcome, when human travel to space. Our study provided evidence that Kupffer cells (KCs) are sensitive to simulated microgravity (SMG), and no similar research report has been found in the literature. Using transcriptome sequencing technology, it was showed that 631 genes were upregulated and 801 genes were downregulated in KCs after treatment under SMG for 3 days. The GO analysis indicated that the proliferation of KCs was affected when exposed to SMG for 3 days. CCK-8 assay confirmed that the proliferation of KCs was inhibited in the third day under the environment of SMG. Furthermore, we identified 8 key genes that affect the proliferation of KCs and predicted 2 transcription factors (TFs) that regulate the 8 key genes. Significantly, we found that microgravity could affect the expression of LMO2 and EZH2 to reduce the transcription of Racgap1, Ccna2, Nek2, Aurka, Plk1, Haus4, Cdc20, Bub1b, which resulting in the reduction in KCs proliferation. These finding suggested that the inhibition of KCs proliferation under microgravity may influence the homeostasis of liver, and LMO2 and EZH2 can be the targets in management of KCs' disturbance in the future practice of space medicine.
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Affiliation(s)
- Jun Ge
- Department of General Surgery, The 306th Hospital of PLA-Peking University Teaching Hospital, Beijing, 100101, China
| | - Yuan Yue
- Department of General Surgery, The 306th Hospital of PLA-Peking University Teaching Hospital, Beijing, 100101, China
| | - Hong-Yun Nie
- Department of General Surgery, The 306th Hospital of PLA-Peking University Teaching Hospital, Beijing, 100101, China
| | - Kai-Ge Liu
- Department of General Surgery, Strategic Support Force Medical Center, Beijing, 100101, China
| | - Hao Li
- Department of General Surgery, Strategic Support Force Medical Center, Beijing, 100101, China.
| | - Hai-Guan Lin
- Department of General Surgery, Strategic Support Force Medical Center, Beijing, 100101, China
| | - Tao Zhang
- Department of General Surgery, Strategic Support Force Medical Center, Beijing, 100101, China
| | - Hong-Feng Yan
- Department of General Surgery, Strategic Support Force Medical Center, Beijing, 100101, China
| | - Hong-Wei Sun
- Department of General Surgery, Strategic Support Force Medical Center, Beijing, 100101, China
| | - Jian-Wu Yang
- Department of General Surgery, Strategic Support Force Medical Center, Beijing, 100101, China
| | - Jin-Lian Zhou
- Department of Pathology, Strategic Support Force Medical Center, Beijing, 100101, China
| | - Yan Cui
- Department of General Surgery, The 306th Hospital of PLA-Peking University Teaching Hospital, Beijing, 100101, China; Department of General Surgery, Strategic Support Force Medical Center, Beijing, 100101, China.
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9
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Valdez V, Ma M, Gouveia B, Zhang R, Petry S. HURP facilitates spindle assembly by stabilizing microtubules and working synergistically with TPX2. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.18.571906. [PMID: 38187686 PMCID: PMC10769297 DOI: 10.1101/2023.12.18.571906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
In large vertebrate spindles, the majority of microtubules are formed via branching microtubule nucleation, whereby microtubules nucleate along the side of pre-existing microtubules. Hepatoma up-regulated protein (HURP) is a microtubule-associated protein that has been implicated in spindle assembly, but its mode of action is yet to be defined. In this study, we show that HURP is necessary for RanGTP-induced branching microtubule nucleation in Xenopus egg extract. Specifically, HURP stabilizes the microtubule lattice to promote microtubule formation from γ-TuRC. This function is shifted to promote branching microtubule nucleation in the presence of TPX2, another branching-promoting factor, as HURP's localization to microtubules is enhanced by TPX2 condensation. Lastly, we provide a structure of HURP on the microtubule lattice, revealing how HURP binding stabilizes the microtubule lattice. We propose a model in which HURP stabilizes microtubules during their formation, and TPX2 preferentially enriches HURP to microtubules to promote branching microtubule nucleation and thus spindle assembly.
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Affiliation(s)
- Venecia Valdez
- Princeton University, Department of Molecular Biology, Princeton, New Jersey, United States
| | - Meisheng Ma
- Department of Biochemistry and Molecular Biophysics, Washington University in St. Louis, School of Medicine (St. Louis, Missouri, United States)
- Present address: Department of Histology and Embryology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology (Wuhan, Hubei, China)
| | - Bernardo Gouveia
- Princeton University, Department of Chemical and Biological Engineering, Princeton, New Jersey, United States
| | - Rui Zhang
- Department of Biochemistry and Molecular Biophysics, Washington University in St. Louis, School of Medicine (St. Louis, Missouri, United States)
| | - Sabine Petry
- Princeton University, Department of Molecular Biology, Princeton, New Jersey, United States
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10
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do Rosário CF, Zhang Y, Stadnicki J, Ross JL, Wadsworth P. Lateral and longitudinal compaction of PRC1 overlap zones drives stabilization of interzonal microtubules. Mol Biol Cell 2023; 34:ar100. [PMID: 37467037 PMCID: PMC10551706 DOI: 10.1091/mbc.e23-02-0049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 06/20/2023] [Accepted: 07/04/2023] [Indexed: 07/20/2023] Open
Abstract
During anaphase, antiparallel-overlapping midzone microtubules elongate and form bundles, contributing to chromosome segregation and the location of contractile ring formation. Midzone microtubules are dynamic in early but not late anaphase; however, the kinetics and mechanisms of stabilization are incompletely understood. Using photoactivation of cells expressing PA-EGFP-α-tubulin we find that immediately after anaphase onset, a single highly dynamic population of midzone microtubules is present; as anaphase progresses, both dynamic and stable populations of midzone microtubules coexist. By mid-cytokinesis, only static, non-dynamic microtubules are detected. The velocity of microtubule sliding also decreases as anaphase progresses, becoming undetectable by late anaphase. Following depletion of PRC1, midzone microtubules remain highly dynamic in anaphase and fail to form static arrays in telophase despite furrowing. Cells depleted of Kif4a contain elongated PRC1 overlap zones and fail to form static arrays in telophase. Cells blocked in cytokinesis form short PRC1 overlap zones that do not coalesce laterally; these cells also fail to form static arrays in telophase. Together, our results demonstrate that dynamic turnover and sliding of midzone microtubules is gradually reduced during anaphase and that the final transition to a static array in telophase requires both lateral and longitudinal compaction of PRC1 containing overlap zones.
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Affiliation(s)
- Carline Fermino do Rosário
- Department of Biology, University of Massachusetts Amherst, Amherst MA 01003
- Program in Molecular and Cellular Biology, University of Massachusetts Amherst, Amherst MA 01003
| | - Ying Zhang
- Department of Biology, University of Massachusetts Amherst, Amherst MA 01003
| | - Jennifer Stadnicki
- Department of Biology, University of Massachusetts Amherst, Amherst MA 01003
- Program in Molecular and Cellular Biology, University of Massachusetts Amherst, Amherst MA 01003
| | | | - Patricia Wadsworth
- Department of Biology, University of Massachusetts Amherst, Amherst MA 01003
- Program in Molecular and Cellular Biology, University of Massachusetts Amherst, Amherst MA 01003
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11
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Kraus J, Alfaro-Aco R, Gouveia B, Petry S. Microtubule nucleation for spindle assembly: one molecule at a time. Trends Biochem Sci 2023; 48:761-775. [PMID: 37482516 PMCID: PMC10789498 DOI: 10.1016/j.tibs.2023.06.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 06/01/2023] [Accepted: 06/06/2023] [Indexed: 07/25/2023]
Abstract
The cell orchestrates the dance of chromosome segregation with remarkable speed and fidelity. The mitotic spindle is built from scratch after interphase through microtubule (MT) nucleation, which is dependent on the γ-tubulin ring complex (γ-TuRC), the universal MT template. Although several MT nucleation pathways build the spindle framework, the question of when and how γ-TuRC is targeted to these nucleation sites in the spindle and subsequently activated remains an active area of investigation. Recent advances facilitated the discovery of new MT nucleation effectors and their mechanisms of action. In this review, we illuminate each spindle assembly pathway and subsequently consider how the pathways are merged to build a spindle.
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Affiliation(s)
- Jodi Kraus
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
| | | | - Bernardo Gouveia
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ, USA
| | - Sabine Petry
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA.
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12
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Valdez VA, Neahring L, Petry S, Dumont S. Mechanisms underlying spindle assembly and robustness. Nat Rev Mol Cell Biol 2023; 24:523-542. [PMID: 36977834 PMCID: PMC10642710 DOI: 10.1038/s41580-023-00584-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/30/2023] [Indexed: 03/30/2023]
Abstract
The microtubule-based spindle orchestrates chromosome segregation during cell division. Following more than a century of study, many components and pathways contributing to spindle assembly have been described, but how the spindle robustly assembles remains incompletely understood. This process involves the self-organization of a large number of molecular parts - up to hundreds of thousands in vertebrate cells - whose local interactions give rise to a cellular-scale structure with emergent architecture, mechanics and function. In this Review, we discuss key concepts in our understanding of spindle assembly, focusing on recent advances and the new approaches that enabled them. We describe the pathways that generate the microtubule framework of the spindle by driving microtubule nucleation in a spatially controlled fashion and present recent insights regarding the organization of individual microtubules into structural modules. Finally, we discuss the emergent properties of the spindle that enable robust chromosome segregation.
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Affiliation(s)
| | - Lila Neahring
- Department of Bioengineering & Therapeutic Sciences, UCSF, San Francisco, CA, USA
- Developmental & Stem Cell Biology Graduate Program, UCSF, San Francisco, CA, USA
| | - Sabine Petry
- Molecular Biology, Princeton University, Princeton, NJ, USA.
| | - Sophie Dumont
- Department of Bioengineering & Therapeutic Sciences, UCSF, San Francisco, CA, USA.
- Developmental & Stem Cell Biology Graduate Program, UCSF, San Francisco, CA, USA.
- Department of Biochemistry & Biophysics, UCSF, San Francisco, CA, USA.
- Chan Zuckerberg Biohub, San Francisco, CA, USA.
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13
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Haruta N, Sumiyoshi E, Honda Y, Terasawa M, Uchiyama C, Toya M, Kubota Y, Sugimoto A. A germline-specific role for unconventional components of the γ-tubulin complex in Caenorhabditis elegans. J Cell Sci 2023; 136:jcs260922. [PMID: 37313686 PMCID: PMC10657210 DOI: 10.1242/jcs.260922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Accepted: 06/07/2023] [Indexed: 06/15/2023] Open
Abstract
The γ-tubulin complex (γTuC) is a widely conserved microtubule nucleator, but some of its components, namely GCP4, GCP5 and GCP6 (also known as TUBGCP4, TUBGCP5 and TUBGCP6, respectively), have not been detected in Caenorhabditis elegans. Here, we identified two γTuC-associated proteins in C. elegans, GTAP-1 and GTAP-2, for which apparent orthologs were detected only in the genus Caenorhabditis. GTAP-1 and GTAP-2 were found to localize at centrosomes and the plasma membrane of the germline, and their centrosomal localization was interdependent. In early C. elegans embryos, whereas the conserved γTuC component MZT-1 (also known as MOZART1 and MZT1) was essential for the localization of centrosomal γ-tubulin, depletion of GTAP-1 and/or GTAP-2 caused up to 50% reduction of centrosomal γ-tubulin and precocious disassembly of spindle poles during mitotic telophase. In the adult germline, GTAP-1 and GTAP-2 contributed to efficient recruitment of the γTuC to the plasma membrane. Depletion of GTAP-1, but not of GTAP-2, severely disrupted both the microtubule array and the honeycomb-like structure of the adult germline. We propose that GTAP-1 and GTAP-2 are unconventional components of the γTuC that contribute to the organization of both centrosomal and non-centrosomal microtubules by targeting the γTuC to specific subcellular sites in a tissue-specific manner.
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Affiliation(s)
- Nami Haruta
- Laboratory of Developmental Dynamics, Graduate School of Life Sciences, Tohoku University, Sendai 980-8577, Japan
| | - Eisuke Sumiyoshi
- Laboratory of Developmental Dynamics, Graduate School of Life Sciences, Tohoku University, Sendai 980-8577, Japan
| | - Yu Honda
- Laboratory of Developmental Dynamics, Graduate School of Life Sciences, Tohoku University, Sendai 980-8577, Japan
| | - Masahiro Terasawa
- Laboratory for Developmental Genomics, RIKEN Center for Developmental Biology, Kobe 650-0047, Japan
| | - Chihiro Uchiyama
- Laboratory of Developmental Dynamics, Graduate School of Life Sciences, Tohoku University, Sendai 980-8577, Japan
| | - Mika Toya
- Laboratory for Developmental Genomics, RIKEN Center for Developmental Biology, Kobe 650-0047, Japan
| | - Yukihiko Kubota
- Laboratory of Developmental Dynamics, Graduate School of Life Sciences, Tohoku University, Sendai 980-8577, Japan
| | - Asako Sugimoto
- Laboratory of Developmental Dynamics, Graduate School of Life Sciences, Tohoku University, Sendai 980-8577, Japan
- Laboratory for Developmental Genomics, RIKEN Center for Developmental Biology, Kobe 650-0047, Japan
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14
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Wang T, Yao S, Li S, Fei X, Zhang M. A prognostic model based on the Augmin family genes for LGG patients. Sci Rep 2023; 13:7520. [PMID: 37161065 PMCID: PMC10170088 DOI: 10.1038/s41598-023-34779-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 05/08/2023] [Indexed: 05/11/2023] Open
Abstract
Gliomas are the most prevalent primary tumors in the central nervous system. Despite some breakthroughs in the treatment of glioma in recent years, survival rates remain low. Although genes of the Augmin family play a key role in microtubule nucleation, the role they play in gliomas is unclear. Transcriptome data were extracted from UCSC XENA and GTEx for low-grade glioma (LGG) and normal tissues, respectively. The protein interaction network associated with Augmin family genes was established using STRING and GeneMANIA databases. Enrichment analysis of gene-related functions and pathways was used to explore potential biological pathways and TIMER to assess immune cell infiltration. Regression analysis and Kaplan-Meier analysis were used to look at the clinical characteristics of the Augmin family genes and the association with the prognosis of patients with glioma. The results showed that the mRNA expression of Augmin family genes was significantly elevated in LGG tissues, except for HAUS7. Immunoregulation, cell cycle, apoptosis and other signaling pathways may be involved in the development and progression of LGG. Except for HAUS4 and HAUS7, the expression of all genes was positively correlated with immune cell infiltration. High expression of HAUS1, HAUS3, HAUS5, HAUS7, HAUS8 and low expression of HAUS4, HAUS6 in LGG was associated with poor prognosis. The risk models constructed based on the pivotal genes HAUS2, HAUS4 and HAUS8 were validated by nomogram and confirmed to be clinically useful for predicting the prognosis of LGG.
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Affiliation(s)
- Tao Wang
- Department of Oncology, The Second Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
| | - Senbang Yao
- Department of Oncology, The Second Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
| | - Siyu Li
- Department of Oncology, The Second Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
| | - Xichang Fei
- Department of Oncology, The Second Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
| | - Mingjun Zhang
- Department of Oncology, The Second Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China.
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15
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Kraus J, Travis SM, King MR, Petry S. Augmin is a Ran-regulated spindle assembly factor. J Biol Chem 2023; 299:104736. [PMID: 37086784 DOI: 10.1016/j.jbc.2023.104736] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 04/03/2023] [Accepted: 04/05/2023] [Indexed: 04/24/2023] Open
Abstract
Mitotic spindles are composed of microtubules (MTs) that must nucleate at the right place and time. Ran regulates this process by directly controlling the release of spindle assembly factors (SAFs) from nucleocytoplasmic shuttle proteins importin-αβ and subsequently forms a biochemical gradient of SAFs localized around chromosomes. The majority of spindle MTs are generated by branching MT nucleation, which has been shown to require an eight-subunit protein complex known as augmin. InXenopus laevis, Ran can control branching through a canonical SAF, TPX2, which is non-essential in Drosophila melanogaster embryos and HeLa cells. Thus, how Ran regulates branching MT nucleation when TPX2 is not required remains unknown. Here, we use in vitro pulldowns and TIRF microscopy to show that augmin is a Ran-regulated SAF. We demonstrate that augmin directly interacts with both importin-α and importin-β through two nuclear localization sequences on the Haus8 subunit, which overlap with the MT binding site. Moreover, we show Ran controls localization of augmin to MTs in both Xenopus egg extract and in vitro. Our results demonstrate that RanGTP directly regulates augmin, which establishes a new way by which Ran controls branching MT nucleation and spindle assembly both in the absence and presence of TPX2.
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Affiliation(s)
- Jodi Kraus
- Department of Molecular Biology; Princeton University; Princeton, NJ, 08544; USA
| | - Sophie M Travis
- Department of Molecular Biology; Princeton University; Princeton, NJ, 08544; USA
| | - Matthew R King
- Department of Molecular Biology; Princeton University; Princeton, NJ, 08544; USA
| | - Sabine Petry
- Department of Molecular Biology; Princeton University; Princeton, NJ, 08544; USA.
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16
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Travis SM, Mahon BP, Huang W, Ma M, Rale MJ, Kraus J, Taylor DJ, Zhang R, Petry S. Integrated model of the vertebrate augmin complex. Nat Commun 2023; 14:2072. [PMID: 37055408 PMCID: PMC10102177 DOI: 10.1038/s41467-023-37519-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 03/17/2023] [Indexed: 04/15/2023] Open
Abstract
Accurate segregation of chromosomes is required to maintain genome integrity during cell division. This feat is accomplished by the microtubule-based spindle. To build a spindle rapidly and with high fidelity, cells take advantage of branching microtubule nucleation, which rapidly amplifies microtubules during cell division. Branching microtubule nucleation relies on the hetero-octameric augmin complex, but lack of structure information about augmin has hindered understanding how it promotes branching. In this work, we combine cryo-electron microscopy, protein structural prediction, and visualization of fused bulky tags via negative stain electron microscopy to identify the location and orientation of each subunit within the augmin structure. Evolutionary analysis shows that augmin's structure is highly conserved across eukaryotes, and that augmin contains a previously unidentified microtubule binding site. Thus, our findings provide insight into the mechanism of branching microtubule nucleation.
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Affiliation(s)
- Sophie M Travis
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
| | - Brian P Mahon
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
- Department of Structural Biology, Bristol Myers Squibb, Princeton, NJ, USA
| | - Wei Huang
- Department of Pharmacology, Case Western Reserve University, Cleveland, OH, USA
| | - Meisheng Ma
- Department of Biochemistry and Molecular Biophysics, Washington University in St. Louis, School of Medicine, St. Louis, MO, USA
- Department of Histology and Embryology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Michael J Rale
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Jodi Kraus
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
| | - Derek J Taylor
- Department of Pharmacology, Case Western Reserve University, Cleveland, OH, USA
| | - Rui Zhang
- Department of Biochemistry and Molecular Biophysics, Washington University in St. Louis, School of Medicine, St. Louis, MO, USA.
| | - Sabine Petry
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA.
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17
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Zhang W, Yang C, Hu Y, Yi K, Xiao W, Xu X, Chen Z. Comprehensive analysis of the correlation of the pan-cancer gene HAUS5 with prognosis and immune infiltration in liver cancer. Sci Rep 2023; 13:2409. [PMID: 36765148 PMCID: PMC9918732 DOI: 10.1038/s41598-023-28653-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Accepted: 01/23/2023] [Indexed: 02/12/2023] Open
Abstract
Liver hepatocellular carcinoma (LIHC) is one of the most common malignancies and places a heavy burden on patients worldwide. HAUS augmin-like complex subunit 5 (HAUS5) is involved in the occurrence and development of various cancers. However, the functional role and significance of HAUS5 in LIHC remain unclear. The Cancer Genome Atlas (TCGA), Genotype-Tissue Expression (GTEx), Cancer Cell Line Encyclopedia (CCLE) and Gene Expression Omnibus (GEO) databases were used to analyze the mRNA expression of HAUS5. The value of HAUS5 in predicting LIHC prognosis and the relationship between HAUS5 and clinicopathological features were assessed by the Kaplan-Meier plotter and UALCAN databases. Functional enrichment analyses and nomogram prediction model construction were performed with the R packages. The LinkedOmics database was searched to reveal co-expressed genes associated with HAUS5. The relationship between HAUS5 expression and immune infiltration was explored by searching the TISIDB database and single-sample gene set enrichment analysis (ssGSEA). The Clinical Proteomic Tumor Analysis Consortium (CPTAC) and the Human Protein Atlas (HPA) databases were used to evaluate HAUS5 protein expression. Finally, the effect of HAUS5 on the proliferation of hepatoma cells was verified by CCK-8, colony formation and EdU assays. HAUS5 is aberrantly expressed and associated with a poor prognosis in most tumors, including LIHC. The expression of HAUS5 is significantly correlated with clinicopathological indicators in patients with LIHC. Functional enrichment analysis showed that HAUS5 was closely related to DNA replication, cell cycle and p53 signaling pathway. HAUS5 may serve as an independent risk factor for LIHC prognosis. The nomogram based on HAUS5 had area under the curve (AUC) values of 0.74 and 0.77 for predicting the 3-year and 5-year overall survival (OS) of LIHC patients. Immune correlation analysis showed that HAUS5 was significantly associated with immune infiltration. Finally, the results of in vitro experiments showed that when HAUS5 was knocked down, the proliferation of hepatoma cells was significantly decreased. The pan-oncogene HAUS5 is a positive regulator of LIHC progression and is closely associated with a poor prognosis in LIHC. Moreover, HAUS5 is involved in immune infiltration in LIHC. HAUS5 may be a new prognostic marker and therapeutic target for LIHC patients.
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Affiliation(s)
- Wenbing Zhang
- Suzhou Medical College of Soochow University, Suzhou, Jiangsu, China
- Department of General Surgery, The First People's Hospital of Taicang, Taicang Affiliated Hospital of Soochow University, No. 58 Changsheng South Road, Taicang, Suzhou, 215400, Jiangsu, People's Republic of China
| | - Chi Yang
- Suzhou Medical College of Soochow University, Suzhou, Jiangsu, China
- Department of General Surgery, The First People's Hospital of Taicang, Taicang Affiliated Hospital of Soochow University, No. 58 Changsheng South Road, Taicang, Suzhou, 215400, Jiangsu, People's Republic of China
| | - Yan Hu
- Central Laboratory, The First People's Hospital of Taicang, Taicang Affiliated Hospital of Soochow University, No. 58 Changsheng South Road, Taicang, Suzhou, 215400, Jiangsu, People's Republic of China
| | - Ke Yi
- Central Laboratory, The First People's Hospital of Taicang, Taicang Affiliated Hospital of Soochow University, No. 58 Changsheng South Road, Taicang, Suzhou, 215400, Jiangsu, People's Republic of China
| | - Wangwen Xiao
- Central Laboratory, The First People's Hospital of Taicang, Taicang Affiliated Hospital of Soochow University, No. 58 Changsheng South Road, Taicang, Suzhou, 215400, Jiangsu, People's Republic of China
| | - Xiaohui Xu
- Suzhou Medical College of Soochow University, Suzhou, Jiangsu, China.
- Department of General Surgery, The First People's Hospital of Taicang, Taicang Affiliated Hospital of Soochow University, No. 58 Changsheng South Road, Taicang, Suzhou, 215400, Jiangsu, People's Republic of China.
- Central Laboratory, The First People's Hospital of Taicang, Taicang Affiliated Hospital of Soochow University, No. 58 Changsheng South Road, Taicang, Suzhou, 215400, Jiangsu, People's Republic of China.
| | - Zhihua Chen
- Suzhou Medical College of Soochow University, Suzhou, Jiangsu, China.
- Department of General Surgery, The First People's Hospital of Taicang, Taicang Affiliated Hospital of Soochow University, No. 58 Changsheng South Road, Taicang, Suzhou, 215400, Jiangsu, People's Republic of China.
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18
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Devate NB, Krishna H, Mishra CN, Manjunath KK, Sunilkumar VP, Chauhan D, Singh S, Sinha N, Jain N, Singh GP, Singh PK. Genetic dissection of marker trait associations for grain micro-nutrients and thousand grain weight under heat and drought stress conditions in wheat. FRONTIERS IN PLANT SCIENCE 2023; 13:1082513. [PMID: 36726675 PMCID: PMC9885108 DOI: 10.3389/fpls.2022.1082513] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 12/15/2022] [Indexed: 06/18/2023]
Abstract
Introduction Wheat is grown and consumed worldwide, making it an important staple food crop for both its calorific and nutritional content. In places where wheat is used as a staple food, suboptimal micronutrient content levels, especially of grain iron (Fe) and zinc (Zn), can lead to malnutrition. Grain nutrient content is influenced by abiotic stresses, such as drought and heat stress. The best method for addressing micronutrient deficiencies is the biofortification of food crops. The prerequisites for marker-assisted varietal development are the identification of the genomic region responsible for high grain iron and zinc contents and an understanding of their genetics. Methods A total of 193 diverse wheat genotypes were evaluated under drought and heat stress conditions across the years at the Indian Agricultural Research Institute (IARI), New Delhi, under timely sown irrigated (IR), restricted irrigated (RI) and late sown (LS) conditions. Grain iron content (GFeC) and grain zinc content (GZnC) were estimated from both the control and treatment groups. Genotyping of all the lines under study was carried out with the single nucleotide polymorphisms (SNPs) from Breeder's 35K Axiom Array. Result and Discussion Three subgroups were observed in the association panel based on both principal component analysis (PCA) and dendrogram analysis. A large whole-genome linkage disequilibrium (LD) block size of 3.49 Mb was observed. A genome-wide association study identified 16 unique stringent marker trait associations for GFeC, GZnC, and 1000-grain weight (TGW). In silico analysis demonstrated the presence of 28 potential candidate genes in the flanking region of 16 linked SNPs, such as synaptotagmin-like mitochondrial-lipid-binding domain, HAUS augmin-like complex, di-copper center-containing domain, protein kinase, chaperonin Cpn60, zinc finger, NUDIX hydrolase, etc. Expression levels of these genes in vegetative tissues and grain were also found. Utilization of identified markers in marker-assisted breeding may lead to the rapid development of biofortified wheat genotypes to combat malnutrition.
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Affiliation(s)
- Narayana Bhat Devate
- Division of Genetics, ICAR-Indian Agricultural research institute, New Delhi, India
| | - Hari Krishna
- Division of Genetics, ICAR-Indian Agricultural research institute, New Delhi, India
| | | | | | - V. P. Sunilkumar
- Division of Genetics, ICAR-Indian Agricultural research institute, New Delhi, India
| | - Divya Chauhan
- Division of Genetics, ICAR-Indian Agricultural research institute, New Delhi, India
| | - Shweta Singh
- Division of Genetics, ICAR-Indian Agricultural research institute, New Delhi, India
| | - Nivedita Sinha
- Division of Genetics, ICAR-Indian Agricultural research institute, New Delhi, India
| | - Neelu Jain
- Division of Genetics, ICAR-Indian Agricultural research institute, New Delhi, India
| | | | - Pradeep Kumar Singh
- Division of Genetics, ICAR-Indian Agricultural research institute, New Delhi, India
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19
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Lafferty MJ, Aygün N, Patel NK, Krupa O, Liang D, Wolter JM, Geschwind DH, de la Torre-Ubieta L, Stein JL. MicroRNA-eQTLs in the developing human neocortex link miR-4707-3p expression to brain size. eLife 2023; 12:e79488. [PMID: 36629315 PMCID: PMC9859047 DOI: 10.7554/elife.79488] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Accepted: 01/10/2023] [Indexed: 01/12/2023] Open
Abstract
Expression quantitative trait loci (eQTL) data have proven important for linking non-coding loci to protein-coding genes. But eQTL studies rarely measure microRNAs (miRNAs), small non-coding RNAs known to play a role in human brain development and neurogenesis. Here, we performed small-RNA sequencing across 212 mid-gestation human neocortical tissue samples, measured 907 expressed miRNAs, discovering 111 of which were novel, and identified 85 local-miRNA-eQTLs. Colocalization of miRNA-eQTLs with GWAS summary statistics yielded one robust colocalization of miR-4707-3p expression with educational attainment and brain size phenotypes, where the miRNA expression increasing allele was associated with decreased brain size. Exogenous expression of miR-4707-3p in primary human neural progenitor cells decreased expression of predicted targets and increased cell proliferation, indicating miR-4707-3p modulates progenitor gene regulation and cell fate decisions. Integrating miRNA-eQTLs with existing GWAS yielded evidence of a miRNA that may influence human brain size and function via modulation of neocortical brain development.
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Affiliation(s)
- Michael J Lafferty
- Department of Genetics, University of North Carolina at Chapel HillChapel HillUnited States
- UNC Neuroscience Center, University of North Carolina at Chapel HillChapel HillUnited States
| | - Nil Aygün
- Department of Genetics, University of North Carolina at Chapel HillChapel HillUnited States
- UNC Neuroscience Center, University of North Carolina at Chapel HillChapel HillUnited States
| | - Niyanta K Patel
- Department of Genetics, University of North Carolina at Chapel HillChapel HillUnited States
- UNC Neuroscience Center, University of North Carolina at Chapel HillChapel HillUnited States
| | - Oleh Krupa
- Department of Genetics, University of North Carolina at Chapel HillChapel HillUnited States
- UNC Neuroscience Center, University of North Carolina at Chapel HillChapel HillUnited States
| | - Dan Liang
- Department of Genetics, University of North Carolina at Chapel HillChapel HillUnited States
- UNC Neuroscience Center, University of North Carolina at Chapel HillChapel HillUnited States
| | - Justin M Wolter
- Department of Genetics, University of North Carolina at Chapel HillChapel HillUnited States
- UNC Neuroscience Center, University of North Carolina at Chapel HillChapel HillUnited States
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel HillChapel HillUnited States
- Carolina Institute for Developmental Disabilities, The University of North Carolina at Chapel HillChapel HillUnited States
| | - Daniel H Geschwind
- Neurogenetics Program, Department of Neurology, David Geffen School of Medicine, University of California, Los AngelesLos AngelesUnited States
- Center for Autism Research and Treatment, Semel Institute, David Geffen School of Medicine, University of California, Los AngelesLos AngelesUnited States
- Department of Human Genetics, David Geffen School of Medicine, University of California, Los AngelesLos AngelesUnited States
- Department of Psychiatry and Biobehavioral Sciences, Semel Institute, David Geffen School of Medicine, University of California, Los AngelesLos AngelesUnited States
| | - Luis de la Torre-Ubieta
- Department of Psychiatry and Biobehavioral Sciences, Semel Institute, David Geffen School of Medicine, University of California, Los AngelesLos AngelesUnited States
| | - Jason L Stein
- Department of Genetics, University of North Carolina at Chapel HillChapel HillUnited States
- UNC Neuroscience Center, University of North Carolina at Chapel HillChapel HillUnited States
- Carolina Institute for Developmental Disabilities, The University of North Carolina at Chapel HillChapel HillUnited States
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20
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Rani B, Gupta DK, Johansson S, Kamranvar SA. Contribution of integrin adhesion to cytokinetic abscission and genomic integrity. Front Cell Dev Biol 2022; 10:1048717. [PMID: 36578785 PMCID: PMC9791049 DOI: 10.3389/fcell.2022.1048717] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 11/28/2022] [Indexed: 12/14/2022] Open
Abstract
Recent research shows that integrin-mediated adhesion contributes to the regulation of cell division at two key steps: the formation of the mitotic spindle at the mitotic entry and the final cytokinetic abscission at the mitotic exit. Failure in either of these processes will have a direct impact on the other in each round of the cell cycle and on the genomic integrity. This review aims to present how integrin signals are involved at these cell cycle stages under normal conditions and some safety mechanisms that may counteract the generation of aneuploid cells in cases of defective integrin signals.
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Affiliation(s)
- Bhavna Rani
- Department of Medical Biochemistry and Microbiology (IMBIM), Biomedical Center, Uppsala University, Uppsala, Sweden
| | - Deepesh K. Gupta
- Department of Pediatrics, Washington University School of Medicine, St. Louis, MO, United States
| | - Staffan Johansson
- Department of Medical Biochemistry and Microbiology (IMBIM), Biomedical Center, Uppsala University, Uppsala, Sweden,*Correspondence: Staffan Johansson, ; Siamak A. Kamranvar,
| | - Siamak A. Kamranvar
- Department of Medical Biochemistry and Microbiology (IMBIM), Biomedical Center, Uppsala University, Uppsala, Sweden,*Correspondence: Staffan Johansson, ; Siamak A. Kamranvar,
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21
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Matković J, Ghosh S, Ćosić M, Eibes S, Barišić M, Pavin N, Tolić IM. Kinetochore- and chromosome-driven transition of microtubules into bundles promotes spindle assembly. Nat Commun 2022; 13:7307. [PMID: 36435852 PMCID: PMC9701229 DOI: 10.1038/s41467-022-34957-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 11/11/2022] [Indexed: 11/28/2022] Open
Abstract
Mitotic spindle assembly is crucial for chromosome segregation and relies on bundles of microtubules that extend from the poles and overlap in the middle. However, how these structures form remains poorly understood. Here we show that overlap bundles arise through a network-to-bundles transition driven by kinetochores and chromosomes. STED super-resolution microscopy reveals that PRC1-crosslinked microtubules initially form loose arrays, which become rearranged into bundles. Kinetochores promote microtubule bundling by lateral binding via CENP-E/kinesin-7 in an Aurora B-regulated manner. Steric interactions between the bundle-associated chromosomes at the spindle midplane drive bundle separation and spindle widening. In agreement with experiments, theoretical modeling suggests that bundles arise through competing attractive and repulsive mechanisms. Finally, perturbation of overlap bundles leads to inefficient correction of erroneous kinetochore-microtubule attachments. Thus, kinetochores and chromosomes drive coarsening of a uniform microtubule array into overlap bundles, which promote not only spindle formation but also chromosome segregation fidelity.
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Affiliation(s)
- Jurica Matković
- grid.4905.80000 0004 0635 7705Division of Molecular Biology, Ruđer Bošković Institute, Zagreb, Croatia
| | - Subhadip Ghosh
- grid.4808.40000 0001 0657 4636Department of Physics, Faculty of Science, University of Zagreb, Zagreb, Croatia
| | - Mateja Ćosić
- grid.4905.80000 0004 0635 7705Division of Molecular Biology, Ruđer Bošković Institute, Zagreb, Croatia
| | - Susana Eibes
- grid.417390.80000 0001 2175 6024Cell Division and Cytoskeleton, Danish Cancer Society Research Center, Copenhagen, Denmark
| | - Marin Barišić
- grid.417390.80000 0001 2175 6024Cell Division and Cytoskeleton, Danish Cancer Society Research Center, Copenhagen, Denmark ,grid.5254.60000 0001 0674 042XDepartment of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Nenad Pavin
- grid.4808.40000 0001 0657 4636Department of Physics, Faculty of Science, University of Zagreb, Zagreb, Croatia
| | - Iva M. Tolić
- grid.4905.80000 0004 0635 7705Division of Molecular Biology, Ruđer Bošković Institute, Zagreb, Croatia
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22
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Štimac V, Koprivec I, Manenica M, Simunić J, Tolić IM. Augmin prevents merotelic attachments by promoting proper arrangement of bridging and kinetochore fibers. eLife 2022; 11:83287. [PMID: 36269126 PMCID: PMC9640188 DOI: 10.7554/elife.83287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 09/26/2022] [Indexed: 11/18/2022] Open
Abstract
The human mitotic spindle is made of microtubules nucleated at centrosomes, at kinetochores, and from pre-existing microtubules by the augmin complex. However, it is unknown how the augmin-mediated nucleation affects distinct microtubule classes and thereby mitotic fidelity. Here, we use superresolution microscopy to analyze the previously indistinguishable microtubule arrangements within the crowded metaphase plate area and demonstrate that augmin is vital for the formation of uniformly arranged parallel units consisting of sister kinetochore fibers connected by a bridging fiber. This ordered geometry helps both prevent and resolve merotelic attachments. Whereas augmin-nucleated bridging fibers prevent merotelic attachments by creating a nearly parallel and highly bundled microtubule arrangement unfavorable for creating additional attachments, augmin-nucleated k-fibers produce robust force required to resolve errors during anaphase. STED microscopy revealed that bridging fibers were impaired twice as much as k-fibers following augmin depletion. The complete absence of bridging fibers from a significant portion of kinetochore pairs, especially in the inner part of the spindle, resulted in the specific reduction of the interkinetochore distance. Taken together, we propose a model where augmin promotes mitotic fidelity by generating assemblies consisting of bridging and kinetochore fibers that align sister kinetochores to face opposite poles, thereby preventing erroneous attachments.
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Affiliation(s)
- Valentina Štimac
- Division of Molecular Biology, Ruđer Bošković Institute, Zagreb, Croatia
| | - Isabella Koprivec
- Division of Molecular Biology, Ruđer Bošković Institute, Zagreb, Croatia
| | - Martina Manenica
- Division of Molecular Biology, Ruđer Bošković Institute, Zagreb, Croatia
| | - Juraj Simunić
- Division of Molecular Biology, Ruđer Bošković Institute, Zagreb, Croatia
| | - Iva M Tolić
- Division of Molecular Biology, Ruđer Bošković Institute, Zagreb, Croatia
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23
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Gomes AM, Orr B, Novais-Cruz M, De Sousa F, Macário-Monteiro J, Lemos C, Ferrás C, Maiato H. Micronuclei from misaligned chromosomes that satisfy the spindle assembly checkpoint in cancer cells. Curr Biol 2022; 32:4240-4254.e5. [PMID: 36057259 PMCID: PMC9559752 DOI: 10.1016/j.cub.2022.08.026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 07/22/2022] [Accepted: 08/11/2022] [Indexed: 12/14/2022]
Abstract
Chromosome alignment to the spindle equator is a hallmark of mitosis thought to promote chromosome segregation fidelity in metazoans. Yet chromosome alignment is only indirectly supervised by the spindle assembly checkpoint (SAC) as a byproduct of chromosome bi-orientation, and the consequences of defective chromosome alignment remain unclear. Here, we investigated how human cells respond to chromosome alignment defects of distinct molecular nature by following the fate of live HeLa cells after RNAi-mediated depletion of 125 proteins previously implicated in chromosome alignment. We confirmed chromosome alignment defects upon depletion of 108/125 proteins. Surprisingly, in all confirmed cases, depleted cells frequently entered anaphase after a delay with misaligned chromosomes. Using depletion of prototype proteins resulting in defective chromosome alignment, we show that misaligned chromosomes often satisfy the SAC and directly missegregate without lagging behind in anaphase. In-depth analysis of specific molecular perturbations that prevent proper kinetochore-microtubule attachments revealed that misaligned chromosomes that missegregate frequently result in micronuclei. Higher-resolution live-cell imaging indicated that, contrary to most anaphase lagging chromosomes that correct and reintegrate the main nuclei, misaligned chromosomes are a strong predictor of micronuclei formation in a cancer cell model of chromosomal instability, but not in non-transformed near-diploid cells. We provide evidence supporting that intrinsic differences in kinetochore-microtubule attachment stability on misaligned chromosomes account for this distinct outcome. Thus, misaligned chromosomes that satisfy the SAC may represent a previously overlooked mechanism driving chromosomal/genomic instability during cancer cell division, and we unveil genetic conditions predisposing for these events.
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Affiliation(s)
- Ana Margarida Gomes
- Chromosome Instability & Dynamics Group, i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua Jorge de Viterbo Ferreira 228, 4050-313 Porto, Portugal
| | - Bernardo Orr
- Chromosome Instability & Dynamics Group, i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal
| | - Marco Novais-Cruz
- Chromosome Instability & Dynamics Group, i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua Jorge de Viterbo Ferreira 228, 4050-313 Porto, Portugal
| | - Filipe De Sousa
- Chromosome Instability & Dynamics Group, i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal
| | - Joana Macário-Monteiro
- Chromosome Instability & Dynamics Group, i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua Jorge de Viterbo Ferreira 228, 4050-313 Porto, Portugal
| | - Carolina Lemos
- Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua Jorge de Viterbo Ferreira 228, 4050-313 Porto, Portugal; UnIGENe, i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal
| | - Cristina Ferrás
- Chromosome Instability & Dynamics Group, i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal
| | - Helder Maiato
- Chromosome Instability & Dynamics Group, i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Cell Division Group, Department of Biomedicine, Faculdade de Medicina, Universidade do Porto, Alameda Prof. Hernâni Monteiro, 4200-319 Porto, Portugal.
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24
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The augmin complex architecture reveals structural insights into microtubule branching. Nat Commun 2022; 13:5635. [PMID: 36163468 PMCID: PMC9512787 DOI: 10.1038/s41467-022-33228-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 09/05/2022] [Indexed: 11/24/2022] Open
Abstract
In mitosis, the augmin complex binds to spindle microtubules to recruit the γ-tubulin ring complex (γ-TuRC), the principal microtubule nucleator, for the formation of branched microtubules. Our understanding of augmin-mediated microtubule branching is hampered by the lack of structural information on the augmin complex. Here, we elucidate the molecular architecture and conformational plasticity of the augmin complex using an integrative structural biology approach. The elongated structure of the augmin complex is characterised by extensive coiled-coil segments and comprises two structural elements with distinct but complementary functions in γ-TuRC and microtubule binding, linked by a flexible hinge. The augmin complex is recruited to microtubules via a composite microtubule binding site comprising a positively charged unordered extension and two calponin homology domains. Our study provides the structural basis for augmin function in branched microtubule formation, decisively fostering our understanding of spindle formation in mitosis. The formation of branched microtubule networks in mitotic spindles depends on the augmin complex. Zupa, Würtz et al. elucidate the molecular architecture and conformational plasticity of the augmin complex using integrative structural biology, providing structural insights into microtubule branching.
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25
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Gabel CA, Li Z, DeMarco AG, Zhang Z, Yang J, Hall MC, Barford D, Chang L. Molecular architecture of the augmin complex. Nat Commun 2022; 13:5449. [PMID: 36114186 PMCID: PMC9481612 DOI: 10.1038/s41467-022-33227-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 09/05/2022] [Indexed: 12/21/2022] Open
Abstract
Accurate segregation of chromosomes during mitosis depends on the correct assembly of the mitotic spindle, a bipolar structure composed mainly of microtubules. The augmin complex, or homologous to augmin subunits (HAUS) complex, is an eight-subunit protein complex required for building robust mitotic spindles in metazoa. Augmin increases microtubule density within the spindle by recruiting the γ-tubulin ring complex (γ-TuRC) to pre-existing microtubules and nucleating branching microtubules. Here, we elucidate the molecular architecture of augmin by single particle cryo-electron microscopy (cryo-EM), computational methods, and crosslinking mass spectrometry (CLMS). Augmin's highly flexible structure contains a V-shaped head and a filamentous tail, with the head existing in either extended or contracted conformational states. Our work highlights how cryo-EM, complemented by computational advances and CLMS, can elucidate the structure of a challenging protein complex and provides insights into the function of augmin in mediating microtubule branching nucleation.
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Affiliation(s)
- Clinton A Gabel
- Department of Biological Sciences, Purdue University, West Lafayette, IN, 47907, USA
- Purdue University Center for Cancer Research, Purdue University, West Lafayette, IN, 47907, USA
| | - Zhuang Li
- Department of Biological Sciences, Purdue University, West Lafayette, IN, 47907, USA
- Purdue University Center for Cancer Research, Purdue University, West Lafayette, IN, 47907, USA
| | - Andrew G DeMarco
- Purdue University Center for Cancer Research, Purdue University, West Lafayette, IN, 47907, USA
- Department of Biochemistry, Purdue University, West Lafayette, IN, 47907, USA
| | - Ziguo Zhang
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK
| | - Jing Yang
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK
| | - Mark C Hall
- Purdue University Center for Cancer Research, Purdue University, West Lafayette, IN, 47907, USA
- Department of Biochemistry, Purdue University, West Lafayette, IN, 47907, USA
| | - David Barford
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK
| | - Leifu Chang
- Department of Biological Sciences, Purdue University, West Lafayette, IN, 47907, USA.
- Purdue University Center for Cancer Research, Purdue University, West Lafayette, IN, 47907, USA.
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26
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Risteski P, Božan D, Jagrić M, Bosilj A, Pavin N, Tolić IM. Length-dependent poleward flux of sister kinetochore fibers promotes chromosome alignment. Cell Rep 2022; 40:111169. [PMID: 35926461 PMCID: PMC9364240 DOI: 10.1016/j.celrep.2022.111169] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 04/20/2022] [Accepted: 07/14/2022] [Indexed: 11/25/2022] Open
Abstract
Chromosome alignment at the spindle equator promotes proper chromosome segregation and depends on pulling forces exerted at kinetochore fiber tips together with polar ejection forces. However, kinetochore fibers are also subjected to forces driving their poleward flux. Here we introduce a flux-driven centering model that relies on flux generated by forces within the overlaps of bridging and kinetochore fibers. This centering mechanism works so that the longer kinetochore fiber fluxes faster than the shorter one, moving the kinetochores toward the center. We develop speckle microscopy in human spindles and confirm the key prediction that kinetochore fiber flux is length dependent. Kinetochores are better centered when overlaps are shorter and the kinetochore fiber flux slower than the bridging fiber flux. We identify Kif18A and Kif4A as overlap and flux regulators and NuMA as a fiber coupler. Thus, length-dependent sliding forces exerted by the bridging fiber onto kinetochore fibers support chromosome alignment. A flux-driven centering model explains chromosome alignment at the spindle equator Kinetochore fiber poleward flux is driven by overlap microtubules Kinetochore centering requires faster flux of the longer sister kinetochore fiber Chromosome alignment depends on the overlap length of bridging microtubules
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Affiliation(s)
- Patrik Risteski
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia
| | - Domagoj Božan
- Department of Physics, Faculty of Science, University of Zagreb, Bijenička cesta 32, 10000 Zagreb, Croatia
| | - Mihaela Jagrić
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia
| | - Agneza Bosilj
- Department of Physics, Faculty of Science, University of Zagreb, Bijenička cesta 32, 10000 Zagreb, Croatia
| | - Nenad Pavin
- Department of Physics, Faculty of Science, University of Zagreb, Bijenička cesta 32, 10000 Zagreb, Croatia.
| | - Iva M Tolić
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia.
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27
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Batman U, Deretic J, Firat-Karalar EN. The ciliopathy protein CCDC66 controls mitotic progression and cytokinesis by promoting microtubule nucleation and organization. PLoS Biol 2022; 20:e3001708. [PMID: 35849559 PMCID: PMC9333452 DOI: 10.1371/journal.pbio.3001708] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 07/28/2022] [Accepted: 06/14/2022] [Indexed: 11/23/2022] Open
Abstract
Precise spatiotemporal control of microtubule nucleation and organization is critical for faithful segregation of cytoplasmic and genetic material during cell division and signaling via the primary cilium in quiescent cells. Microtubule-associated proteins (MAPs) govern assembly, maintenance, and remodeling of diverse microtubule arrays. While a set of conserved MAPs are only active during cell division, an emerging group of MAPs acts as dual regulators in dividing and nondividing cells. Here, we elucidated the nonciliary functions and molecular mechanism of action of the ciliopathy-linked protein CCDC66, which we previously characterized as a regulator of ciliogenesis in quiescent cells. We showed that CCDC66 dynamically localizes to the centrosomes, the bipolar spindle, the spindle midzone, the central spindle, and the midbody in dividing cells and interacts with the core machinery of centrosome maturation and MAPs involved in cell division. Loss-of-function experiments revealed its functions during mitotic progression and cytokinesis. Specifically, CCDC66 depletion resulted in defective spindle assembly and orientation, kinetochore fiber stability, chromosome alignment in metaphase as well as central spindle and midbody assembly and organization in anaphase and cytokinesis. Notably, CCDC66 regulates mitotic microtubule nucleation via noncentrosomal and centrosomal pathways via recruitment of gamma-tubulin to the centrosomes and the spindle. Additionally, CCDC66 bundles microtubules in vitro and in cells by its C-terminal microtubule-binding domain. Phenotypic rescue experiments showed that the microtubule and centrosome-associated pools of CCDC66 individually or cooperatively mediate its mitotic and cytokinetic functions. Collectively, our findings identify CCDC66 as a multifaceted regulator of the nucleation and organization of the diverse mitotic and cytokinetic microtubule arrays and provide new insight into nonciliary defects that underlie ciliopathies. The ciliopathy-linked protein CCDC66 is only known for its ciliary functions. This study reveals that CCDC66 also has extensive non-ciliary functions, localizing to the spindle poles, spindle midzone, central spindle and midbody throughout cell division, where it regulates mitosis and cytokinesis by promoting microtubule nucleation and organization.
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Affiliation(s)
- Umut Batman
- Department of Molecular Biology and Genetics, Koç University, Istanbul, Turkey
| | - Jovana Deretic
- Department of Molecular Biology and Genetics, Koç University, Istanbul, Turkey
| | - Elif Nur Firat-Karalar
- Department of Molecular Biology and Genetics, Koç University, Istanbul, Turkey
- Koç University School of Medicine, Istanbul, Turkey
- * E-mail:
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28
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HAUS Augmin-Like Complex Subunit 1 Influences Tumour Microenvironment and Prognostic Outcomes in Glioma. JOURNAL OF ONCOLOGY 2022; 2022:8027686. [PMID: 35865089 PMCID: PMC9296284 DOI: 10.1155/2022/8027686] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 05/09/2022] [Accepted: 05/17/2022] [Indexed: 11/18/2022]
Abstract
Background. The expression of HAUS Augmin-like complex subunit 1 (HAUS1), a protein-coding gene, is low in normal samples among various cancers with pan-cancer analysis. The depletion of HAUS1 in cells decreases the G2/M cell compartment and induces apoptosis. However, the detailed expression pattern of HAUS1 and its correlation with immune infiltration in glioma (LGG and GBM) (LGG: low-grade glioma; GBM: glioblastoma) remain unknown. Therefore, in this study, we examined the role and prognostic value of HAUS1 in glioma. Methods. Transcriptional expression data of HAUS1 were collected from the CGGA and TCGA databases. The Kaplan–Meier analysis, univariate and multivariate Cox analyses, and receiver operating characteristic (ROC) curves were used to analyse the clinical significance of HAUS1 in glioma. The STRING database was used to analyse protein-protein interactions (PPI), and the “ClusterProfiler” package was used for functional enrichment analysis to examine the possible biological roles of HAUS1. In addition, the HAUS1 promoter methylation modification was analysed using MEXPRESS, and the association between HAUS1 expression and tumour-infiltrating immune cells was investigated using CIBERSORT. Results. Based on the data retrieved from TCGA (703 samples) and CGGA (1018 samples), an elevated expression of HAUS1 was observed in glioma samples, which was associated with poorer survival of patients, unfavourable clinical characteristics, 1p/19q codeletion status, WHO grade, and IDH mutation status. Furthermore, multivariate and univariate Cox analyses revealed that HAUS1 was an independent predictor of glioma. HAUS1 expression level was associated with several tumour-infiltrating immune cells, such as Th2 cells, macrophages, and activated dendritic cells. The outcomes of ROC curve analysis showed that HAUS1 was good to prognosticate immune infiltrating levels in glioma with a higher area under the curve (AUC) value (AUC = 0.974). Conclusions. HAUS1 was upregulated and served as a biomarker for poor prognosis in patients with glioma. High HAUS1 expression was associated with several tumour-infiltrating immune cells such as Th2 cells, macrophages, and activated dendritic cells, which had high infiltration levels. Therefore, these findings suggest that HAUS1 is a potential biomarker for predicting the prognosis of patients with glioma and plays a pivotal role in immune infiltration in glioma.
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Popova JV, Pavlova GA, Razuvaeva AV, Yarinich LA, Andreyeva EN, Anders AF, Galimova YA, Renda F, Somma MP, Pindyurin AV, Gatti M. Genetic Control of Kinetochore-Driven Microtubule Growth in Drosophila Mitosis. Cells 2022; 11:cells11142127. [PMID: 35883570 PMCID: PMC9323100 DOI: 10.3390/cells11142127] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 06/28/2022] [Accepted: 06/29/2022] [Indexed: 01/08/2023] Open
Abstract
Centrosome-containing cells assemble their spindles exploiting three main classes of microtubules (MTs): MTs nucleated by the centrosomes, MTs generated near the chromosomes/kinetochores, and MTs nucleated within the spindle by the augmin-dependent pathway. Mammalian and Drosophila cells lacking the centrosomes generate MTs at kinetochores and eventually form functional bipolar spindles. However, the mechanisms underlying kinetochore-driven MT formation are poorly understood. One of the ways to elucidate these mechanisms is the analysis of spindle reassembly following MT depolymerization. Here, we used an RNA interference (RNAi)-based reverse genetics approach to dissect the process of kinetochore-driven MT regrowth (KDMTR) after colcemid-induced MT depolymerization. This MT depolymerization procedure allows a clear assessment of KDMTR, as colcemid disrupts centrosome-driven MT regrowth but not KDMTR. We examined KDMTR in normal Drosophila S2 cells and in S2 cells subjected to RNAi against conserved genes involved in mitotic spindle assembly: mast/orbit/chb (CLASP1), mei-38 (TPX2), mars (HURP), dgt6 (HAUS6), Eb1 (MAPRE1/EB1), Patronin (CAMSAP2), asp (ASPM), and Klp10A (KIF2A). RNAi-mediated depletion of Mast/Orbit, Mei-38, Mars, Dgt6, and Eb1 caused a significant delay in KDMTR, while loss of Patronin had a milder negative effect on this process. In contrast, Asp or Klp10A deficiency increased the rate of KDMTR. These results coupled with the analysis of GFP-tagged proteins (Mast/Orbit, Mei-38, Mars, Eb1, Patronin, and Asp) localization during KDMTR suggested a model for kinetochore-dependent spindle reassembly. We propose that kinetochores capture the plus ends of MTs nucleated in their vicinity and that these MTs elongate at kinetochores through the action of Mast/Orbit. The Asp protein binds the MT minus ends since the beginning of KDMTR, preventing excessive and disorganized MT regrowth. Mei-38, Mars, Dgt6, Eb1, and Patronin positively regulate polymerization, bundling, and stabilization of regrowing MTs until a bipolar spindle is reformed.
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Affiliation(s)
- Julia V. Popova
- Institute of Molecular and Cellular Biology, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (J.V.P.); (G.A.P.); (A.V.R.); (L.A.Y.); (E.N.A.); (A.F.A.); (Y.A.G.)
- Laboratory of Bioengineering, Novosibirsk State Agrarian University, 630039 Novosibirsk, Russia
| | - Gera A. Pavlova
- Institute of Molecular and Cellular Biology, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (J.V.P.); (G.A.P.); (A.V.R.); (L.A.Y.); (E.N.A.); (A.F.A.); (Y.A.G.)
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Alyona V. Razuvaeva
- Institute of Molecular and Cellular Biology, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (J.V.P.); (G.A.P.); (A.V.R.); (L.A.Y.); (E.N.A.); (A.F.A.); (Y.A.G.)
- Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - Lyubov A. Yarinich
- Institute of Molecular and Cellular Biology, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (J.V.P.); (G.A.P.); (A.V.R.); (L.A.Y.); (E.N.A.); (A.F.A.); (Y.A.G.)
- Faculty of Natural Sciences, Novosibirsk State University, 630090 Novosibirsk, Russia
| | - Evgeniya N. Andreyeva
- Institute of Molecular and Cellular Biology, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (J.V.P.); (G.A.P.); (A.V.R.); (L.A.Y.); (E.N.A.); (A.F.A.); (Y.A.G.)
| | - Alina F. Anders
- Institute of Molecular and Cellular Biology, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (J.V.P.); (G.A.P.); (A.V.R.); (L.A.Y.); (E.N.A.); (A.F.A.); (Y.A.G.)
| | - Yuliya A. Galimova
- Institute of Molecular and Cellular Biology, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (J.V.P.); (G.A.P.); (A.V.R.); (L.A.Y.); (E.N.A.); (A.F.A.); (Y.A.G.)
| | - Fioranna Renda
- Institute of Molecular Biology and Pathology (IBPM), National Research Council (CNR), c/o Department of Biology and Biotechnology, Sapienza University of Rome, 00185 Rome, Italy; (F.R.); (M.P.S.)
| | - Maria Patrizia Somma
- Institute of Molecular Biology and Pathology (IBPM), National Research Council (CNR), c/o Department of Biology and Biotechnology, Sapienza University of Rome, 00185 Rome, Italy; (F.R.); (M.P.S.)
| | - Alexey V. Pindyurin
- Institute of Molecular and Cellular Biology, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (J.V.P.); (G.A.P.); (A.V.R.); (L.A.Y.); (E.N.A.); (A.F.A.); (Y.A.G.)
- Correspondence: (A.V.P.); (M.G.)
| | - Maurizio Gatti
- Institute of Molecular and Cellular Biology, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia; (J.V.P.); (G.A.P.); (A.V.R.); (L.A.Y.); (E.N.A.); (A.F.A.); (Y.A.G.)
- Institute of Molecular Biology and Pathology (IBPM), National Research Council (CNR), c/o Department of Biology and Biotechnology, Sapienza University of Rome, 00185 Rome, Italy; (F.R.); (M.P.S.)
- Correspondence: (A.V.P.); (M.G.)
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30
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Zhang Y, Hong X, Hua S, Jiang K. Reconstitution and mechanistic dissection of the human microtubule branching machinery. J Cell Biol 2022; 221:e202109053. [PMID: 35604367 PMCID: PMC9129923 DOI: 10.1083/jcb.202109053] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 03/07/2022] [Accepted: 05/02/2022] [Indexed: 01/07/2023] Open
Abstract
Branching microtubule (MT) nucleation is mediated by the augmin complex and γ-tubulin ring complex (γ-TuRC). However, how these two complexes work together to promote this process remains elusive. Here, using purified components from native and recombinant sources, we demonstrate that human augmin and γ-TuRC are sufficient to reconstitute the minimal MT branching machinery, in which NEDD1 bridges between augmin holo complex and GCP3/MZT1 subcomplex of γ-TuRC. The single-molecule experiment suggests that oligomerization of augmin may activate the branching machinery. We provide direct biochemical evidence that CDK1- and PLK1-dependent phosphorylation are crucial for NEDD1 binding to augmin, for their synergistic MT-binding activities, and hence for branching MT nucleation. In addition, we unveil that NEDD1 possesses an unanticipated intrinsic affinity for MTs via its WD40 domain, which also plays a pivotal role in the branching process. In summary, our study provides a comprehensive understanding of the underlying mechanisms of branching MT nucleation in human cells.
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Affiliation(s)
- Yaqian Zhang
- The State Key Laboratory Breeding Base of Basic Science of Stomatology and Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, China
- Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Wuhan University, Wuhan, China
| | - Xing Hong
- The State Key Laboratory Breeding Base of Basic Science of Stomatology and Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, China
- Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Wuhan University, Wuhan, China
| | - Shasha Hua
- The State Key Laboratory Breeding Base of Basic Science of Stomatology and Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, China
- Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Wuhan University, Wuhan, China
| | - Kai Jiang
- The State Key Laboratory Breeding Base of Basic Science of Stomatology and Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, China
- Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Wuhan University, Wuhan, China
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31
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Fidler G, Szilágyi-Rácz AA, Dávid P, Tolnai E, Rejtő L, Szász R, Póliska S, Biró S, Paholcsek M. Circulating microRNA sequencing revealed miRNome patterns in hematology and oncology patients aiding the prognosis of invasive aspergillosis. Sci Rep 2022; 12:7144. [PMID: 35504997 PMCID: PMC9065123 DOI: 10.1038/s41598-022-11239-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 04/18/2022] [Indexed: 11/20/2022] Open
Abstract
Invasive aspergillosis (IA) may occur as a serious complication of hematological malignancy. Delays in antifungal therapy can lead to an invasive disease resulting in high mortality. Currently, there are no well-established blood circulating microRNA biomarkers or laboratory tests which can be used to diagnose IA. Therefore, we aimed to define dysregulated miRNAs in hematology and oncology (HO) patients to identify biomarkers predisposing disease. We performed an in-depth analysis of high-throughput small transcriptome sequencing data obtained from the whole blood samples of our study cohort of 50 participants including 26 high-risk HO patients and 24 controls. By integrating in silico bioinformatic analyses of small noncoding RNA data, 57 miRNAs exhibiting significant expression differences (P < 0.05) were identified between IA-infected patients and non-IA HO patients. Among these, we found 36 differentially expressed miRNAs (DEMs) irrespective of HO malignancy. Of the top ranked DEMs, we found 14 significantly deregulated miRNAs, whose expression levels were successfully quantified by qRT-PCR. MiRNA target prediction revealed the involvement of IA related miRNAs in the biological pathways of tumorigenesis, the cell cycle, the immune response, cell differentiation and apoptosis.
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Affiliation(s)
- Gábor Fidler
- Department of Human Genetics, Faculty of Medicine, University of Debrecen, Egyetem tér 1., 4032, Debrecen, Hungary
| | - Anna Anita Szilágyi-Rácz
- Department of Human Genetics, Faculty of Medicine, University of Debrecen, Egyetem tér 1., 4032, Debrecen, Hungary
| | - Péter Dávid
- Department of Human Genetics, Faculty of Medicine, University of Debrecen, Egyetem tér 1., 4032, Debrecen, Hungary
| | - Emese Tolnai
- Department of Human Genetics, Faculty of Medicine, University of Debrecen, Egyetem tér 1., 4032, Debrecen, Hungary
| | - László Rejtő
- Department of Hematology, Jósa András Teaching Hospital, Nyíregyháza, Hungary
| | - Róbert Szász
- Division of Hematology, Institute of Internal Medicine, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Szilárd Póliska
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Sándor Biró
- Department of Human Genetics, Faculty of Medicine, University of Debrecen, Egyetem tér 1., 4032, Debrecen, Hungary
| | - Melinda Paholcsek
- Department of Human Genetics, Faculty of Medicine, University of Debrecen, Egyetem tér 1., 4032, Debrecen, Hungary.
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32
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The chirality of the mitotic spindle provides a mechanical response to forces and depends on microtubule motors and augmin. Curr Biol 2022; 32:2480-2493.e6. [PMID: 35537456 PMCID: PMC9235856 DOI: 10.1016/j.cub.2022.04.035] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 02/17/2022] [Accepted: 04/13/2022] [Indexed: 12/24/2022]
Abstract
Forces produced by motor proteins and microtubule dynamics within the mitotic spindle are crucial for proper chromosome segregation. In addition to linear forces, rotational forces or torques are present in the spindle, which are reflected in the left-handed twisted shapes of microtubule bundles that make the spindle chiral. However, the biological role and molecular origins of spindle chirality are unknown. By developing methods for measuring the spindle twist, we show that spindles are most chiral near the metaphase-to-anaphase transition. To assess the role of chirality in spindle mechanics, we compressed the spindles along their axis. This resulted in a stronger left-handed twist, suggesting that the twisted shape allows for a mechanical response to forces. Inhibition or depletion of motor proteins that perform chiral stepping, Eg5/kinesin-5, Kif18A/kinesin-8, MKLP1/kinesin-6, and dynein, decreased the left-handed twist or led to right-handed twist, implying that these motors regulate the twist by rotating microtubules within their antiparallel overlaps or at the spindle pole. A right-handed twist was also observed after the depletion of the microtubule nucleator augmin, indicating its contribution to the twist through the nucleation of antiparallel bridging microtubules. The uncovered switch from left-handed to right-handed twist reveals the existence of competing mechanisms that promote twisting in opposite directions. As round spindles are more twisted than the elongated ones are, we infer that bending and twisting moments are generated by similar molecular mechanisms and propose a physiological role for spindle chirality in allowing the spindle to absorb mechanical load. Video abstract
Spindle twist depends on torque-generating motors Eg5, Kif18A, MKLP1, and dynein Without the microtubule nucleator augmin, spindles show right-handed twist Compression of the spindle along the axis increases the left-handed twist Rounder spindles are more twisted than elongated ones are
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Almeida AC, Soares-de-Oliveira J, Drpic D, Cheeseman LP, Damas J, Lewin HA, Larkin DM, Aguiar P, Pereira AJ, Maiato H. Augmin-dependent microtubule self-organization drives kinetochore fiber maturation in mammals. Cell Rep 2022; 39:110610. [PMID: 35385739 PMCID: PMC8994134 DOI: 10.1016/j.celrep.2022.110610] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 01/07/2022] [Accepted: 03/11/2022] [Indexed: 11/29/2022] Open
Abstract
Chromosome segregation in mammals relies on the maturation of a thick bundle of kinetochore-attached microtubules known as k-fiber. How k-fibers mature from initial kinetochore microtubule attachments remains a fundamental question. By combining molecular perturbations and phenotypic analyses in Indian muntjac fibroblasts containing the lowest known diploid chromosome number in mammals (2N = 6) and distinctively large kinetochores, with fixed/live-cell super-resolution coherent-hybrid stimulated emission depletion (CH-STED) nanoscopy and laser microsurgery, we demonstrate a key role for augmin in kinetochore microtubule self-organization and maturation, regardless of pioneer centrosomal microtubules. In doing so, augmin promotes kinetochore and interpolar microtubule turnover and poleward flux. Tracking of microtubule growth events within individual k-fibers reveals a wide angular dispersion, consistent with augmin-mediated branched microtubule nucleation. Augmin depletion reduces the frequency of kinetochore microtubule growth events and hampers efficient repair after acute k-fiber injury by laser microsurgery. Together, these findings underscore the contribution of augmin-mediated microtubule amplification for k-fiber self-organization and maturation in mammals.
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Affiliation(s)
- Ana C Almeida
- Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal
| | - Joana Soares-de-Oliveira
- Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal
| | - Danica Drpic
- Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal
| | - Liam P Cheeseman
- Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal
| | - Joana Damas
- Department of Comparative Biomedical Sciences, Royal Veterinary College, University of London, London NW1 0TU, UK; Department of Evolution and Ecology, University of California, Davis, CA 95616, USA
| | - Harris A Lewin
- Department of Evolution and Ecology, University of California, Davis, CA 95616, USA
| | - Denis M Larkin
- Department of Comparative Biomedical Sciences, Royal Veterinary College, University of London, London NW1 0TU, UK
| | - Paulo Aguiar
- Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto Nacional de Engenharia Biomédica (INEB), Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal
| | - António J Pereira
- Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal
| | - Helder Maiato
- Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Cell Division Group, Department of Biomedicine, Faculdade de Medicina, Universidade do Porto, Alameda Professor Hernâni Monteiro, 4200-319 Porto, Portugal.
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34
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Lera-Ramirez M, Nédélec FJ, Tran PT. Microtubule rescue at midzone edges promotes overlap stability and prevents spindle collapse during anaphase B. eLife 2022; 11:72630. [PMID: 35293864 PMCID: PMC9018073 DOI: 10.7554/elife.72630] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 03/15/2022] [Indexed: 11/14/2022] Open
Abstract
During anaphase B, molecular motors slide interpolar microtubules to elongate the mitotic spindle, contributing to the separation of chromosomes. However, sliding of antiparallel microtubules reduces their overlap, which may lead to spindle breakage, unless microtubules grow to compensate sliding. How sliding and growth are coordinated is still poorly understood. In this study, we have used the fission yeast S. pombe to measure microtubule dynamics during anaphase B. We report that the coordination of microtubule growth and sliding relies on promoting rescues at the midzone edges. This makes microtubules stable from pole to midzone, while their distal parts including the plus ends alternate between assembly and disassembly. Consequently, the midzone keeps a constant length throughout anaphase, enabling sustained sliding without the need for a precise regulation of microtubule growth speed. Additionally, we found that in S. pombe, which undergoes closed mitosis, microtubule growth speed decreases when the nuclear membrane wraps around the spindle midzone.
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Microtubule and Actin Cytoskeletal Dynamics in Male Meiotic Cells of Drosophila melanogaster. Cells 2022; 11:cells11040695. [PMID: 35203341 PMCID: PMC8870657 DOI: 10.3390/cells11040695] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Revised: 02/11/2022] [Accepted: 02/14/2022] [Indexed: 01/12/2023] Open
Abstract
Drosophila dividing spermatocytes offer a highly suitable cell system in which to investigate the coordinated reorganization of microtubule and actin cytoskeleton systems during cell division of animal cells. Like male germ cells of mammals, Drosophila spermatogonia and spermatocytes undergo cleavage furrow ingression during cytokinesis, but abscission does not take place. Thus, clusters of primary and secondary spermatocytes undergo meiotic divisions in synchrony, resulting in cysts of 32 secondary spermatocytes and then 64 spermatids connected by specialized structures called ring canals. The meiotic spindles in Drosophila males are substantially larger than the spindles of mammalian somatic cells and exhibit prominent central spindles and contractile rings during cytokinesis. These characteristics make male meiotic cells particularly amenable to immunofluorescence and live imaging analysis of the spindle microtubules and the actomyosin apparatus during meiotic divisions. Moreover, because the spindle assembly checkpoint is not robust in spermatocytes, Drosophila male meiosis allows investigating of whether gene products required for chromosome segregation play additional roles during cytokinesis. Here, we will review how the research studies on Drosophila male meiotic cells have contributed to our knowledge of the conserved molecular pathways that regulate spindle microtubules and cytokinesis with important implications for the comprehension of cancer and other diseases.
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36
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Verma V, Maresca TJ. A celebration of the 25th anniversary of chromatin-mediated spindle assembly. Mol Biol Cell 2022; 33:rt1. [PMID: 35076260 PMCID: PMC9236140 DOI: 10.1091/mbc.e21-08-0400] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Formation of a bipolar spindle is required for the faithful segregation of chromosomes during cell division. Twenty-five years ago, a transformative insight into how bipolarity is achieved was provided by Rebecca Heald, Eric Karsenti, and colleagues in their landmark publication characterizing a chromatin-mediated spindle assembly pathway in which centrosomes and kinetochores were dispensable. The discovery revealed that bipolar spindle assembly is a self-organizing process where microtubules, which possess an intrinsic polarity, polymerize around chromatin and become sorted by mitotic motors into a bipolar structure. On the 25th anniversary of this seminal paper, we discuss what was known before, what we have learned since, and what may lie ahead in understanding the bipolar spindle.
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Affiliation(s)
- Vikash Verma
- Biology Department, University of Massachusetts, Amherst, Amherst, MA 01003
| | - Thomas J Maresca
- Biology Department, University of Massachusetts, Amherst, Amherst, MA 01003.,Molecular and Cellular Biology Graduate Program, University of Massachusetts, Amherst, Amherst, MA 01003
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37
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Keep Calm and Carry on with Extra Centrosomes. Cancers (Basel) 2022; 14:cancers14020442. [PMID: 35053604 PMCID: PMC8774008 DOI: 10.3390/cancers14020442] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 01/01/2022] [Accepted: 01/03/2022] [Indexed: 02/01/2023] Open
Abstract
Simple Summary Precise chromosome segregation during mitosis is a vital event orchestrated by formation of bipolar spindle poles. Supernumerary centrosomes, caused by centrosome amplification, deteriorates mitotic processes, resulting in segregation defects leading to chromosomal instability (CIN). Centrosome amplification is frequently observed in various types of cancer and considered as a significant contributor to destabilization of chromosomes. This review provides a comprehensive overview of causes and consequences of centrosome amplification thoroughly describing molecular mechanisms. Abstract Aberrations in the centrosome number and structure can readily be detected at all stages of tumor progression and are considered hallmarks of cancer. Centrosome anomalies are closely linked to chromosome instability and, therefore, are proposed to be one of the driving events of tumor formation and progression. This concept, first posited by Boveri over 100 years ago, has been an area of interest to cancer researchers. We have now begun to understand the processes by which these numerical and structural anomalies may lead to cancer, and vice-versa: how key events that occur during carcinogenesis could lead to amplification of centrosomes. Despite the proliferative advantages that having extra centrosomes may confer, their presence can also lead to loss of essential genetic material as a result of segregational errors and cancer cells must deal with these deadly consequences. Here, we review recent advances in the current literature describing the mechanisms by which cancer cells amplify their centrosomes and the methods they employ to tolerate the presence of these anomalies, focusing particularly on centrosomal clustering.
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Schweizer N, Haren L, Dutto I, Viais R, Lacasa C, Merdes A, Lüders J. Sub-centrosomal mapping identifies augmin-γTuRC as part of a centriole-stabilizing scaffold. Nat Commun 2021; 12:6042. [PMID: 34654813 PMCID: PMC8519919 DOI: 10.1038/s41467-021-26252-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Accepted: 09/22/2021] [Indexed: 11/08/2022] Open
Abstract
Centriole biogenesis and maintenance are crucial for cells to generate cilia and assemble centrosomes that function as microtubule organizing centers (MTOCs). Centriole biogenesis and MTOC function both require the microtubule nucleator γ-tubulin ring complex (γTuRC). It is widely accepted that γTuRC nucleates microtubules from the pericentriolar material that is associated with the proximal part of centrioles. However, γTuRC also localizes more distally and in the centriole lumen, but the significance of these findings is unclear. Here we identify spatially and functionally distinct subpopulations of centrosomal γTuRC. Luminal localization is mediated by augmin, which is linked to the centriole inner scaffold through POC5. Disruption of luminal localization impairs centriole integrity and interferes with cilium assembly. Defective ciliogenesis is also observed in γTuRC mutant fibroblasts from a patient suffering from microcephaly with chorioretinopathy. These results identify a non-canonical role of augmin-γTuRC in the centriole lumen that is linked to human disease.
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Affiliation(s)
- Nina Schweizer
- Mechanisms of Disease Programme, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), 08028, Barcelona, Spain
| | - Laurence Haren
- Molecular, Cellular and Developmental Biology, Centre de Biologie Intégrative, CNRS-Université Toulouse III, 31062, Toulouse, France
| | - Ilaria Dutto
- Mechanisms of Disease Programme, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), 08028, Barcelona, Spain
| | - Ricardo Viais
- Mechanisms of Disease Programme, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), 08028, Barcelona, Spain
| | - Cristina Lacasa
- Mechanisms of Disease Programme, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), 08028, Barcelona, Spain
| | - Andreas Merdes
- Molecular, Cellular and Developmental Biology, Centre de Biologie Intégrative, CNRS-Université Toulouse III, 31062, Toulouse, France
| | - Jens Lüders
- Mechanisms of Disease Programme, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), 08028, Barcelona, Spain.
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39
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Vukušić K, Tolić IM. Anaphase B: Long-standing models meet new concepts. Semin Cell Dev Biol 2021; 117:127-139. [PMID: 33849764 PMCID: PMC8406420 DOI: 10.1016/j.semcdb.2021.03.023] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 03/26/2021] [Accepted: 03/28/2021] [Indexed: 12/16/2022]
Abstract
Mitotic cell divisions ensure stable transmission of genetic information from a mother to daughter cells in a series of generations. To ensure this crucial task is accomplished, the cell forms a bipolar structure called the mitotic spindle that divides sister chromatids to the opposite sides of the dividing mother cell. After successful establishment of stable attachments of microtubules to chromosomes and inspection of connections between them, at the heart of mitosis, the cell starts the process of segregation. This spectacular moment in the life of a cell is termed anaphase, and it involves two distinct processes: depolymerization of microtubules bound to chromosomes, which is also known as anaphase A, and elongation of the spindle or anaphase B. Both processes ensure physical separation of disjointed sister chromatids. In this chapter, we review the mechanisms of anaphase B spindle elongation primarily in mammalian systems, combining different pioneering ideas and concepts with more recent findings that shed new light on the force generation and regulation of biochemical modules operating during spindle elongation. Finally, we present a comprehensive model of spindle elongation that includes structural, biophysical, and molecular aspects of anaphase B.
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Affiliation(s)
- Kruno Vukušić
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia.
| | - Iva M Tolić
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia.
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40
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Viais R, Fariña-Mosquera M, Villamor-Payà M, Watanabe S, Palenzuela L, Lacasa C, Lüders J. Augmin deficiency in neural stem cells causes p53-dependent apoptosis and aborts brain development. eLife 2021; 10:67989. [PMID: 34427181 PMCID: PMC8456695 DOI: 10.7554/elife.67989] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 08/16/2021] [Indexed: 01/01/2023] Open
Abstract
Microtubules that assemble the mitotic spindle are generated by centrosomal nucleation, chromatin-mediated nucleation, and nucleation from the surface of other microtubules mediated by the augmin complex. Impairment of centrosomal nucleation in apical progenitors of the developing mouse brain induces p53-dependent apoptosis and causes non-lethal microcephaly. Whether disruption of non-centrosomal nucleation has similar effects is unclear. Here, we show, using mouse embryos, that conditional knockout of the augmin subunit Haus6 in apical progenitors led to spindle defects and mitotic delay. This triggered massive apoptosis and abortion of brain development. Co-deletion of Trp53 rescued cell death, but surviving progenitors failed to organize a pseudostratified epithelium, and brain development still failed. This could be explained by exacerbated mitotic errors and resulting chromosomal defects including increased DNA damage. Thus, in contrast to centrosomes, augmin is crucial for apical progenitor mitosis, and, even in the absence of p53, for progression of brain development.
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Affiliation(s)
- Ricardo Viais
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Marcos Fariña-Mosquera
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Marina Villamor-Payà
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Sadanori Watanabe
- Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya, Japan
| | - Lluís Palenzuela
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Cristina Lacasa
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Jens Lüders
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
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41
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Abstract
As one of four filament types, microtubules are a core component of the cytoskeleton and are essential for cell function. Yet how microtubules are nucleated from their building blocks, the αβ-tubulin heterodimer, has remained a fundamental open question since the discovery of tubulin 50 years ago. Recent structural studies have shed light on how γ-tubulin and the γ-tubulin complex proteins (GCPs) GCP2 to GCP6 form the γ-tubulin ring complex (γ-TuRC). In parallel, functional and single-molecule studies have informed on how the γ-TuRC nucleates microtubules in real time, how this process is regulated in the cell and how it compares to other modes of nucleation. Another recent surprise has been the identification of a second essential nucleation factor, which turns out to be the well-characterized microtubule polymerase XMAP215 (also known as CKAP5, a homolog of chTOG, Stu2 and Alp14). This discovery helps to explain why the observed nucleation activity of the γ-TuRC in vitro is relatively low. Taken together, research in recent years has afforded important insight into how microtubules are made in the cell and provides a basis for an exciting era in the cytoskeleton field.
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Affiliation(s)
- Akanksha Thawani
- California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, Berkeley, CA 94720, USA
| | - Sabine Petry
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
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42
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Hu L, Chen Y, Yang CP, Huang Y, Song NN, Chen JY, Sun YL, Ding YQ, Lang B. Ulk4, a Newly Discovered Susceptibility Gene for Schizophrenia, Regulates Corticogenesis in Mice. Front Cell Dev Biol 2021; 9:645368. [PMID: 34235142 PMCID: PMC8255617 DOI: 10.3389/fcell.2021.645368] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 04/23/2021] [Indexed: 11/13/2022] Open
Abstract
Schizophrenia (SCZ) is a chronic and severe mental disease that affects around 1% of the population. The precise etiology of SCZ still remains largely unknown, and no conclusive mechanisms are firmly established. Recent advances in epidemiological and clinical investigation support an overwhelmingly strong neurodevelopmental origin for SCZ. Here, we demonstrated that Unc-51-like kinase 4 (Ulk4), a novel risk factor for major mental disorders including schizophrenia, is involved in the corticogenesis. Deletion of Ulk4 in mice led to significantly thinner layers of II–III, and V in the cerebral cortex, which was confirmed in conditional Ulk4 deletion mice achieved by Cre-loxp strategy. This abnormality might be caused by decreased intermediate neural progenitors and increased apoptosis. Thus, our data suggest that Ulk4 manipulates the behaviors of neural progenitors during brain development and, when functionally defective, leads to the reduction of specific cortical layers. This anomaly may increase predisposition to a range of neurodevelopmental disorders, including SCZ.
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Affiliation(s)
- Ling Hu
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Yi Chen
- Key Laboratory of Arrhythmias, Ministry of Education, East Hospital, and Department of Anatomy and Neurobiology, Tongji University School of Medicine, Shanghai, China
| | - Cui-Ping Yang
- Key Laboratory of Arrhythmias, Ministry of Education, East Hospital, and Department of Anatomy and Neurobiology, Tongji University School of Medicine, Shanghai, China
| | - Ying Huang
- Department of Laboratory Animal Science, Fudan University, Shanghai, China
| | - Ning-Ning Song
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Jia-Yin Chen
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Yu-Ling Sun
- Key Laboratory of Arrhythmias, Ministry of Education, East Hospital, and Department of Anatomy and Neurobiology, Tongji University School of Medicine, Shanghai, China
| | - Yu-Qiang Ding
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China.,Key Laboratory of Arrhythmias, Ministry of Education, East Hospital, and Department of Anatomy and Neurobiology, Tongji University School of Medicine, Shanghai, China.,Department of Laboratory Animal Science, Fudan University, Shanghai, China
| | - Bing Lang
- National Clinical Research Centre for Mental Health, Department of Psychiatry, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
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43
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Ferreira LT, Maiato H. Prometaphase. Semin Cell Dev Biol 2021; 117:52-61. [PMID: 34127384 DOI: 10.1016/j.semcdb.2021.06.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 05/31/2021] [Accepted: 06/02/2021] [Indexed: 11/28/2022]
Abstract
The establishment of a metaphase plate in which all chromosomes are attached to mitotic spindle microtubules and aligned at the cell equator is required for faithful chromosome segregation in metazoans. The achievement of this configuration relies on the precise coordination between several concurrent mechanisms that start upon nuclear envelope breakdown, mediate chromosome capture at their kinetochores during mitotic spindle assembly and culminate with the congression of all chromosomes to the spindle equator. This period is called 'prometaphase'. Because the nature of chromosome capture by mitotic spindle microtubules is error prone, the cell is provided of error correction mechanisms that sense and correct most erroneous kinetochore-microtubule attachments before committing to separate sister chromatids in anaphase. In this review, aimed for newcomers in the field, more than providing an exhaustive mechanistic coverage of each and every concurrent mechanism taking place during prometaphase, we provide an integrative overview of these processes that ultimately promote the subsequent faithful segregation of chromosomes during mitosis.
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Affiliation(s)
- Luísa T Ferreira
- Chromosome Instability & Dynamics Group, i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal
| | - Helder Maiato
- Chromosome Instability & Dynamics Group, i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Cell Division Group, Experimental Biology Unit, Department of Biomedicine, Faculdade de Medicina, Universidade do Porto, Alameda Prof. Hernâni Monteiro, 4200-319 Porto, Portugal.
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44
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Barisic M, Rajendraprasad G, Steblyanko Y. The metaphase spindle at steady state - Mechanism and functions of microtubule poleward flux. Semin Cell Dev Biol 2021; 117:99-117. [PMID: 34053864 DOI: 10.1016/j.semcdb.2021.05.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 05/13/2021] [Accepted: 05/13/2021] [Indexed: 11/24/2022]
Abstract
The mitotic spindle is a bipolar cellular structure, built from tubulin polymers, called microtubules, and interacting proteins. This macromolecular machine orchestrates chromosome segregation, thereby ensuring accurate distribution of genetic material into the two daughter cells during cell division. Powered by GTP hydrolysis upon tubulin polymerization, the microtubule ends exhibit a metastable behavior known as the dynamic instability, during which they stochastically switch between the growth and shrinkage phases. In the context of the mitotic spindle, dynamic instability is furthermore regulated by microtubule-associated proteins and motor proteins, which enables the spindle to undergo profound changes during mitosis. This highly dynamic behavior is essential for chromosome capture and congression in prometaphase, as well as for chromosome alignment to the spindle equator in metaphase and their segregation in anaphase. In this review we focus on the mechanisms underlying microtubule dynamics and sliding and their importance for the maintenance of shape, structure and dynamics of the metaphase spindle. We discuss how these spindle properties are related to the phenomenon of microtubule poleward flux, highlighting its highly cooperative molecular basis and role in keeping the metaphase spindle at a steady state.
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Affiliation(s)
- Marin Barisic
- Cell Division and Cytoskeleton, Danish Cancer Society Research Center (DCRC), Strandboulevarden 49, 2100 Copenhagen, Denmark; Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark.
| | - Girish Rajendraprasad
- Cell Division and Cytoskeleton, Danish Cancer Society Research Center (DCRC), Strandboulevarden 49, 2100 Copenhagen, Denmark
| | - Yulia Steblyanko
- Cell Division and Cytoskeleton, Danish Cancer Society Research Center (DCRC), Strandboulevarden 49, 2100 Copenhagen, Denmark
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45
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Abstract
During anaphase, a microtubule-containing structure called the midzone forms between the segregating chromosomes. The midzone is composed of an antiparallel array of microtubules and numerous microtubule-associated proteins that contribute to midzone formation and function. In many cells, the midzone is an important source of signals that specify the location of contractile ring assembly and constriction. The midzone also contributes to the events of anaphase by generating forces that impact chromosome segregation and spindle elongation; some midzone components contribute to both processes. The results of recent experiments have increased our understanding of the importance of the midzone, a microtubule array that has often been overlooked. This Journal of Cell Science at a Glance article will review, and illustrate on the accompanying poster, the organization, formation and dynamics of the midzone, and discuss open questions for future research.
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Affiliation(s)
- Patricia Wadsworth
- Department of Biology, Morrill Science Center, University of Massachusetts, 611 N. Pleasant Street, Amherst 01003, USA
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46
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Baião GC, Janice J, Galinou M, Klasson L. Comparative Genomics Reveals Factors Associated with Phenotypic Expression of Wolbachia. Genome Biol Evol 2021; 13:6277727. [PMID: 34003269 DOI: 10.1093/gbe/evab111] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 05/05/2021] [Accepted: 05/17/2021] [Indexed: 12/18/2022] Open
Abstract
Wolbachia is a widespread, vertically transmitted bacterial endosymbiont known for manipulating arthropod reproduction. Its most common form of reproductive manipulation is cytoplasmic incompatibility (CI), observed when a modification in the male sperm leads to embryonic lethality unless a compatible rescue factor is present in the female egg. CI attracts scientific attention due to its implications for host speciation and in the use of Wolbachia for controlling vector-borne diseases. However, our understanding of CI is complicated by the complexity of the phenotype, whose expression depends on both symbiont and host factors. In the present study, we perform a comparative analysis of nine complete Wolbachia genomes with known CI properties in the same genetic host background, Drosophila simulans STC. We describe genetic differences between closely related strains and uncover evidence that phages and other mobile elements contribute to the rapid evolution of both genomes and phenotypes of Wolbachia. Additionally, we identify both known and novel genes associated with the modification and rescue functions of CI. We combine our observations with published phenotypic information and discuss how variability in cif genes, novel CI-associated genes, and Wolbachia titer might contribute to poorly understood aspects of CI such as strength and bidirectional incompatibility. We speculate that high titer CI strains could be better at invading new hosts already infected with a CI Wolbachia, due to a higher rescue potential, and suggest that titer might thus be a relevant parameter to consider for future strategies using CI Wolbachia in biological control.
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Affiliation(s)
- Guilherme Costa Baião
- Molecular Evolution, Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Jessin Janice
- Molecular Evolution, Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Maria Galinou
- Molecular Evolution, Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Lisa Klasson
- Molecular Evolution, Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
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47
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Setru SU, Gouveia B, Alfaro-Aco R, Shaevitz JW, Stone HA, Petry S. A hydrodynamic instability drives protein droplet formation on microtubules to nucleate branches. NATURE PHYSICS 2021; 17:493-498. [PMID: 35211183 PMCID: PMC8865447 DOI: 10.1038/s41567-020-01141-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 11/24/2020] [Indexed: 05/23/2023]
Affiliation(s)
- Sagar U. Setru
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
| | - Bernardo Gouveia
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA
| | - Raymundo Alfaro-Aco
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - Joshua W. Shaevitz
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
- Department of Physics, Princeton University, Princeton, NJ 08544, USA
| | - Howard A. Stone
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544, USA
| | - Sabine Petry
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
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48
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Dubé MP, Legault MA, Lemaçon A, Lemieux Perreault LP, Fouodjio R, Waters DD, Kouz S, Pinto FJ, Maggioni AP, Diaz R, Berry C, Koenig W, Lopez-Sendon J, Gamra H, Kiwan GS, Asselin G, Provost S, Barhdadi A, Sun M, Cossette M, Blondeau L, Mongrain I, Dubois A, Rhainds D, Bouabdallaoui N, Samuel M, de Denus S, L'Allier PL, Guertin MC, Roubille F, Tardif JC. Pharmacogenomics of the Efficacy and Safety of Colchicine in COLCOT. CIRCULATION-GENOMIC AND PRECISION MEDICINE 2021; 14:e003183. [PMID: 33560138 PMCID: PMC8284376 DOI: 10.1161/circgen.120.003183] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Supplemental Digital Content is available in the text. Background: The randomized, placebo-controlled COLCOT (Colchicine Cardiovascular Outcomes Trial) has shown the benefits of colchicine 0.5 mg daily to lower the rate of ischemic cardiovascular events in patients with a recent myocardial infarction. Here, we conducted a post hoc pharmacogenomic study of COLCOT with the aim to identify genetic predictors of the efficacy and safety of treatment with colchicine. Methods: There were 1522 participants of European ancestry from the COLCOT trial available for the pharmacogenomic study of COLCOT trial. The pharmacogenomic study’s primary cardiovascular end point was defined as for the main trial, as time to first occurrence of cardiovascular death, resuscitated cardiac arrest, myocardial infarction, stroke, or urgent hospitalization for angina requiring coronary revascularization. The safety end point was time to the first report of gastrointestinal events. Patients’ DNA was genotyped using the Illumina Global Screening array followed by imputation. We performed a genome-wide association study in colchicine-treated patients. Results: None of the genetic variants passed the genome-wide association study significance threshold for the primary cardiovascular end point conducted in 702 patients in the colchicine arm who were compliant to medication. The genome-wide association study for gastrointestinal events was conducted in all 767 patients in the colchicine arm and found 2 significant association signals, one with lead variant rs6916345 (hazard ratio, 1.89 [95% CI, 1.52–2.35], P=7.41×10−9) in a locus which colocalizes with Crohn disease, and one with lead variant rs74795203 (hazard ratio, 2.51 [95% CI, 1.82–3.47]; P=2.70×10−8), an intronic variant in gene SEPHS1. The interaction terms between the genetic variants and treatment with colchicine versus placebo were significant. Conclusions: We found 2 genomic regions associated with gastrointestinal events in patients treated with colchicine. Those findings will benefit from replication to confirm that some patients may have genetic predispositions to lower tolerability of treatment with colchicine.
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Affiliation(s)
- Marie-Pierre Dubé
- Montreal Heart Institute (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., M.C., L.B., I.M., A.D., D.R., N.B., M.S., S.d.D., P.L.L., M.-C.G., J.-C.T.), Université de Montréal, Canada.,Université de Montréal Beaulieu-Saucier Pharmacogenomics Centre (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., I.M., A.D., S.d.D.), Université de Montréal, Canada.,Department of Medicine (M.-P.D., A.L., M.S., N.B., M.S., J.-C.T.), Université de Montréal, Canada
| | - Marc-André Legault
- Montreal Heart Institute (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., M.C., L.B., I.M., A.D., D.R., N.B., M.S., S.d.D., P.L.L., M.-C.G., J.-C.T.), Université de Montréal, Canada.,Université de Montréal Beaulieu-Saucier Pharmacogenomics Centre (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., I.M., A.D., S.d.D.), Université de Montréal, Canada.,Departments of Biochemistry and Molecular Medicine, Faculty of Medicine (M.-A.L.), Université de Montréal, Canada
| | - Audrey Lemaçon
- Montreal Heart Institute (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., M.C., L.B., I.M., A.D., D.R., N.B., M.S., S.d.D., P.L.L., M.-C.G., J.-C.T.), Université de Montréal, Canada.,Université de Montréal Beaulieu-Saucier Pharmacogenomics Centre (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., I.M., A.D., S.d.D.), Université de Montréal, Canada.,Department of Medicine (M.-P.D., A.L., M.S., N.B., M.S., J.-C.T.), Université de Montréal, Canada
| | - Louis-Philippe Lemieux Perreault
- Montreal Heart Institute (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., M.C., L.B., I.M., A.D., D.R., N.B., M.S., S.d.D., P.L.L., M.-C.G., J.-C.T.), Université de Montréal, Canada.,Université de Montréal Beaulieu-Saucier Pharmacogenomics Centre (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., I.M., A.D., S.d.D.), Université de Montréal, Canada
| | - René Fouodjio
- Montreal Heart Institute (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., M.C., L.B., I.M., A.D., D.R., N.B., M.S., S.d.D., P.L.L., M.-C.G., J.-C.T.), Université de Montréal, Canada.,Université de Montréal Beaulieu-Saucier Pharmacogenomics Centre (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., I.M., A.D., S.d.D.), Université de Montréal, Canada
| | | | - Simon Kouz
- Centre Hospitalier Régional de Lanaudière, Joliette, Canada (S.K.)
| | - Fausto J Pinto
- Santa Maria University Hospital (CHULN), CAML, CCUL, Faculdade de Medicina da Universidade de Lisboa, Portugal (F.J.P.)
| | - Aldo P Maggioni
- Maria Cecilia Hospital, GVM Care and Research, Italy (A.P.M.)
| | - Rafael Diaz
- Estudios Clinicos Latinoamerica, Rosario, Argentina (R.D.)
| | - Colin Berry
- University of Glasgow, NHS Glasgow Clinical Research Facility, United Kingsom (C.B.)
| | - Wolfgang Koenig
- Deutsches Herzzentrum München, Technische Universität München, Munich, Germany (W.K.).,DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Munich, Germany (W.K.).,Institute of Epidemiology and Medical Biometry, University of Ulm, Germany (W.K.)
| | | | - Habib Gamra
- Fattouma Bourguiba University Hospital, Monastir, Tunisia (H.G.)
| | | | - Géraldine Asselin
- Montreal Heart Institute (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., M.C., L.B., I.M., A.D., D.R., N.B., M.S., S.d.D., P.L.L., M.-C.G., J.-C.T.), Université de Montréal, Canada.,Université de Montréal Beaulieu-Saucier Pharmacogenomics Centre (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., I.M., A.D., S.d.D.), Université de Montréal, Canada
| | - Sylvie Provost
- Montreal Heart Institute (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., M.C., L.B., I.M., A.D., D.R., N.B., M.S., S.d.D., P.L.L., M.-C.G., J.-C.T.), Université de Montréal, Canada.,Université de Montréal Beaulieu-Saucier Pharmacogenomics Centre (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., I.M., A.D., S.d.D.), Université de Montréal, Canada
| | - Amina Barhdadi
- Montreal Heart Institute (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., M.C., L.B., I.M., A.D., D.R., N.B., M.S., S.d.D., P.L.L., M.-C.G., J.-C.T.), Université de Montréal, Canada.,Université de Montréal Beaulieu-Saucier Pharmacogenomics Centre (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., I.M., A.D., S.d.D.), Université de Montréal, Canada
| | - Maxine Sun
- Montreal Heart Institute (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., M.C., L.B., I.M., A.D., D.R., N.B., M.S., S.d.D., P.L.L., M.-C.G., J.-C.T.), Université de Montréal, Canada.,Université de Montréal Beaulieu-Saucier Pharmacogenomics Centre (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., I.M., A.D., S.d.D.), Université de Montréal, Canada.,Department of Medicine (M.-P.D., A.L., M.S., N.B., M.S., J.-C.T.), Université de Montréal, Canada
| | - Mariève Cossette
- Montreal Heart Institute (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., M.C., L.B., I.M., A.D., D.R., N.B., M.S., S.d.D., P.L.L., M.-C.G., J.-C.T.), Université de Montréal, Canada.,Montreal Health Innovation Coordinating Centre, Canada (M.C., L.B., M.-C.G.)
| | - Lucie Blondeau
- Montreal Heart Institute (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., M.C., L.B., I.M., A.D., D.R., N.B., M.S., S.d.D., P.L.L., M.-C.G., J.-C.T.), Université de Montréal, Canada.,Montreal Health Innovation Coordinating Centre, Canada (M.C., L.B., M.-C.G.)
| | - Ian Mongrain
- Montreal Heart Institute (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., M.C., L.B., I.M., A.D., D.R., N.B., M.S., S.d.D., P.L.L., M.-C.G., J.-C.T.), Université de Montréal, Canada.,Université de Montréal Beaulieu-Saucier Pharmacogenomics Centre (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., I.M., A.D., S.d.D.), Université de Montréal, Canada
| | - Anick Dubois
- Montreal Heart Institute (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., M.C., L.B., I.M., A.D., D.R., N.B., M.S., S.d.D., P.L.L., M.-C.G., J.-C.T.), Université de Montréal, Canada.,Université de Montréal Beaulieu-Saucier Pharmacogenomics Centre (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., I.M., A.D., S.d.D.), Université de Montréal, Canada
| | - David Rhainds
- Montreal Heart Institute (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., M.C., L.B., I.M., A.D., D.R., N.B., M.S., S.d.D., P.L.L., M.-C.G., J.-C.T.), Université de Montréal, Canada
| | - Nadia Bouabdallaoui
- Montreal Heart Institute (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., M.C., L.B., I.M., A.D., D.R., N.B., M.S., S.d.D., P.L.L., M.-C.G., J.-C.T.), Université de Montréal, Canada.,Department of Medicine (M.-P.D., A.L., M.S., N.B., M.S., J.-C.T.), Université de Montréal, Canada
| | - Michelle Samuel
- Montreal Heart Institute (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., M.C., L.B., I.M., A.D., D.R., N.B., M.S., S.d.D., P.L.L., M.-C.G., J.-C.T.), Université de Montréal, Canada.,Department of Medicine (M.-P.D., A.L., M.S., N.B., M.S., J.-C.T.), Université de Montréal, Canada
| | - Simon de Denus
- Montreal Heart Institute (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., M.C., L.B., I.M., A.D., D.R., N.B., M.S., S.d.D., P.L.L., M.-C.G., J.-C.T.), Université de Montréal, Canada.,Université de Montréal Beaulieu-Saucier Pharmacogenomics Centre (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., I.M., A.D., S.d.D.), Université de Montréal, Canada.,Université de Montréal, Faculty of Pharmacy, Canada (S.d.D.)
| | - Philippe L L'Allier
- Montreal Heart Institute (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., M.C., L.B., I.M., A.D., D.R., N.B., M.S., S.d.D., P.L.L., M.-C.G., J.-C.T.), Université de Montréal, Canada
| | - Marie-Claude Guertin
- Montreal Heart Institute (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., M.C., L.B., I.M., A.D., D.R., N.B., M.S., S.d.D., P.L.L., M.-C.G., J.-C.T.), Université de Montréal, Canada.,Montreal Health Innovation Coordinating Centre, Canada (M.C., L.B., M.-C.G.)
| | - François Roubille
- PhyMedExp (Physiologie et Médecine Expérimentale du Coeur et des Muscles), Université de Montpellier, INSERM, Centre National de la Recherche Scientifique, Cardiology Department, CHU de Montpellier, France (F.R.)
| | - Jean-Claude Tardif
- Montreal Heart Institute (M.-P.D., M.-A.L., A.L., L.-P.L.P., R.F., G.A., S.P., A.B., M.S., M.C., L.B., I.M., A.D., D.R., N.B., M.S., S.d.D., P.L.L., M.-C.G., J.-C.T.), Université de Montréal, Canada.,Department of Medicine (M.-P.D., A.L., M.S., N.B., M.S., J.-C.T.), Université de Montréal, Canada
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49
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Preuss F, Chatterjee D, Mathea S, Shrestha S, St-Germain J, Saha M, Kannan N, Raught B, Rottapel R, Knapp S. Nucleotide Binding, Evolutionary Insights, and Interaction Partners of the Pseudokinase Unc-51-like Kinase 4. Structure 2020; 28:1184-1196.e6. [PMID: 32814032 DOI: 10.1016/j.str.2020.07.016] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 06/17/2020] [Accepted: 07/29/2020] [Indexed: 01/11/2023]
Abstract
Unc-51-like kinase 4 (ULK4) is a pseudokinase that has been linked to the development of several diseases. Even though sequence motifs required for ATP binding in kinases are lacking, ULK4 still tightly binds ATP and the presence of the co-factor is required for structural stability of ULK4. Here, we present a high-resolution structure of a ULK4-ATPγS complex revealing a highly unusual ATP binding mode in which the lack of the canonical VAIK motif lysine is compensated by K39, located N-terminal to αC. Evolutionary analysis suggests that degradation of active site motifs in metazoan ULK4 has co-occurred with an ULK4-specific activation loop, which stabilizes the C helix. In addition, cellular interaction studies using BioID and biochemical validation data revealed high confidence interactors of the pseudokinase and armadillo repeat domains. Many of the identified ULK4 interaction partners were centrosomal and tubulin-associated proteins and several active kinases suggesting interesting regulatory roles for ULK4.
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Affiliation(s)
- Franziska Preuss
- Institute for Pharmaceutical Chemistry, Johann Wolfgang Goethe-University, Max-von-Laue-Str. 9, 60438 Frankfurt am Main, Germany; Buchmann Institute for Molecular Life Sciences, Structural Genomics Consortium, Johann Wolfgang Goethe-University, Max-von-Laue-Str. 15, 60438 Frankfurt am Main, Germany
| | - Deep Chatterjee
- Institute for Pharmaceutical Chemistry, Johann Wolfgang Goethe-University, Max-von-Laue-Str. 9, 60438 Frankfurt am Main, Germany; Buchmann Institute for Molecular Life Sciences, Structural Genomics Consortium, Johann Wolfgang Goethe-University, Max-von-Laue-Str. 15, 60438 Frankfurt am Main, Germany
| | - Sebastian Mathea
- Institute for Pharmaceutical Chemistry, Johann Wolfgang Goethe-University, Max-von-Laue-Str. 9, 60438 Frankfurt am Main, Germany; Buchmann Institute for Molecular Life Sciences, Structural Genomics Consortium, Johann Wolfgang Goethe-University, Max-von-Laue-Str. 15, 60438 Frankfurt am Main, Germany
| | - Safal Shrestha
- Institute of Bioinformatics & Department of Biochemistry and Molecular Biology, University of Georgia, 120 Green Street, Athens, GA 30602-7229, USA
| | - Jonathan St-Germain
- Princess Margaret Cancer Centre, University Health Network, Toronto M5G 2C4, Canada
| | - Manipa Saha
- Princess Margaret Cancer Centre, University Health Network, Toronto M5G 2C4, Canada
| | - Natarajan Kannan
- Institute of Bioinformatics & Department of Biochemistry and Molecular Biology, University of Georgia, 120 Green Street, Athens, GA 30602-7229, USA
| | - Brian Raught
- Princess Margaret Cancer Centre, University Health Network, Toronto M5G 2C4, Canada
| | - Robert Rottapel
- Princess Margaret Cancer Centre, University Health Network, Toronto M5G 2C4, Canada; Departments of Medicine, Immunology and Medical Biophysics, University of Toronto, Toronto M5G 1L7, Canada; Division of Rheumatology, St. Michael's Hospital, Toronto M5B 1W8, Canada
| | - Stefan Knapp
- Institute for Pharmaceutical Chemistry, Johann Wolfgang Goethe-University, Max-von-Laue-Str. 9, 60438 Frankfurt am Main, Germany; Buchmann Institute for Molecular Life Sciences, Structural Genomics Consortium, Johann Wolfgang Goethe-University, Max-von-Laue-Str. 15, 60438 Frankfurt am Main, Germany; German Cancer Consortium (DKTK) and Frankfurt Cancer Institute (FCI), 60596 Frankfurt am Main, Germany.
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Microtubule Organization in Striated Muscle Cells. Cells 2020; 9:cells9061395. [PMID: 32503326 PMCID: PMC7349303 DOI: 10.3390/cells9061395] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 05/25/2020] [Accepted: 05/28/2020] [Indexed: 12/13/2022] Open
Abstract
Distinctly organized microtubule networks contribute to the function of differentiated cell types such as neurons, epithelial cells, skeletal myotubes, and cardiomyocytes. In striated (i.e., skeletal and cardiac) muscle cells, the nuclear envelope acts as the dominant microtubule-organizing center (MTOC) and the function of the centrosome—the canonical MTOC of mammalian cells—is attenuated, a common feature of differentiated cell types. We summarize the mechanisms known to underlie MTOC formation at the nuclear envelope, discuss the significance of the nuclear envelope MTOC for muscle function and cell cycle progression, and outline potential mechanisms of centrosome attenuation.
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