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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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Gong T, McNally KL, Konanoor S, Peraza A, Bailey C, Redemann S, McNally FJ. Roles of Tubulin Concentration during Prometaphase and Ran-GTP during Anaphase of C. elegans meiosis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.19.590357. [PMID: 38659754 PMCID: PMC11042349 DOI: 10.1101/2024.04.19.590357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
In many animal species, the oocyte meiotic spindle, which is required for chromosome segregation, forms without centrosomes. In some systems, Ran-GEF on chromatin initiates spindle assembly. We found that in C. elegans oocytes, endogenously-tagged Ran-GEF dissociates from chromatin during spindle assembly but re-associates during meiotic anaphase. Meiotic spindle assembly occurred after auxin-induced degradation of Ran-GEF but anaphase I was faster than controls and extrusion of the first polar body frequently failed. In search of a possible alternative pathway for spindle assembly, we found that soluble tubulin concentrates in the nuclear volume during germinal vesicle breakdown. We found that the concentration of soluble tubulin in the metaphase spindle region is enclosed by ER sheets which exclude cytoplasmic organelles including mitochondria and yolk granules. Measurement of the volume occupied by yolk granules and mitochondria indicated that volume exclusion would be sufficient to explain the concentration of tubulin in the spindle volume. We suggest that this concentration of soluble tubulin may be a redundant mechanism promoting spindle assembly near chromosomes.
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Affiliation(s)
- Ting Gong
- Department of Molecular and Cellular Biology, university of California, Davis, Davis, CA 95616, USA
| | - Karen L McNally
- Department of Molecular and Cellular Biology, university of California, Davis, Davis, CA 95616, USA
| | - Siri Konanoor
- Department of Molecular and Cellular Biology, university of California, Davis, Davis, CA 95616, USA
| | - Alma Peraza
- Department of Molecular and Cellular Biology, university of California, Davis, Davis, CA 95616, USA
| | - Cynthia Bailey
- Department of Molecular and Cellular Biology, university of California, Davis, Davis, CA 95616, USA
| | - Stefanie Redemann
- Department of Cell Biology, University of Virginia, School of Medicine, Charlottesville, VA, USA
| | - Francis J McNally
- Department of Molecular and Cellular Biology, university of California, Davis, Davis, CA 95616, USA
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Huang Y, Lu C, Wang H, Gu L, Fu YX, Li GM. DNAJA2 deficiency activates cGAS-STING pathway via the induction of aberrant mitosis and chromosome instability. Nat Commun 2023; 14:5246. [PMID: 37640708 PMCID: PMC10462666 DOI: 10.1038/s41467-023-40952-0] [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: 10/20/2022] [Accepted: 08/17/2023] [Indexed: 08/31/2023] Open
Abstract
Molecular chaperone HSP70s are attractive targets for cancer therapy, but their substrate broadness and functional non-specificity have limited their role in therapeutical success. Functioning as HSP70's cochaperones, HSP40s determine the client specificity of HSP70s, and could be better targets for cancer therapy. Here we show that tumors defective in HSP40 member DNAJA2 are benefitted from immune-checkpoint blockade (ICB) therapy. Mechanistically, DNAJA2 maintains centrosome homeostasis by timely degrading key centriolar satellite proteins PCM1 and CEP290 via HSC70 chaperone-mediated autophagy (CMA). Tumor cells depleted of DNAJA2 or CMA factor LAMP2A exhibit elevated levels of centriolar satellite proteins, which causes aberrant mitosis characterized by abnormal spindles, chromosome missegregation and micronuclei formation. This activates the cGAS-STING pathway to enhance ICB therapy response in tumors derived from DNAJA2-deficient cells. Our study reveals a role for DNAJA2 to regulate mitotic division and chromosome stability and suggests DNAJA2 as a potential target to enhance cancer immunotherapy, thereby providing strategies to advance HSPs-based cancer therapy.
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Affiliation(s)
- Yaping Huang
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Changzheng Lu
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Institute of Cancer Research, Shenzhen Bay Laboratory, Shenzhen, China
| | - Hanzhi Wang
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Liya Gu
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Yang-Xin Fu
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
- Department of Basic Medical Sciences, Tsinghua University School of Medicine, Beijing, China.
| | - Guo-Min Li
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
- Chinese Institutes for Medical Research, Beijing, China.
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4
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Ignacio DP, Kravtsova N, Henry J, Palomares RH, Dawes AT. Dynein localization and pronuclear movement in the C. elegans zygote. Cytoskeleton (Hoboken) 2022; 79:133-143. [PMID: 36214774 PMCID: PMC10092226 DOI: 10.1002/cm.21733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 10/02/2022] [Accepted: 10/04/2022] [Indexed: 01/30/2023]
Abstract
Centrosomes serve as a site for microtubule nucleation and these microtubules will grow and interact with the motor protein dynein at the cortex. The position of the centrosomes determines where the mitotic spindle will develop across all cell types. Centrosome positioning is achieved through dynein and microtubule-mediated force generation. The mechanism and regulation of force generation during centrosome positioning are not fully understood. Centrosome and pronuclear movement in the first cell cycle of the Caenorhabditis elegans early embryo undergoes both centration and rotation prior to cell division. The proteins LET-99 and GPB-1 have been postulated to have a role in force generation associated with pronuclear centration and rotation dynamics. When the expression of these proteins is perturbed, pronuclear positioning exhibits a movement defect characterized by oscillatory ("wobble") behavior of the pronuclear complex (PNC). To determine if this movement defect is due to an effect on cortical dynein distribution, we utilize RNAi-mediated knockdown of LET-99 and GPB-1 to induce wobble and assay for any effects on GFP-tagged dynein localization in the early C. elegans embryo. To compare and quantify the movement defect produced by the knockdown of LET-99 and GPB-1, we devised a quantification method that measures the strength of wobble ("wobble metric") observed under these experimental conditions. Our quantification of pronuclear complex dynamics and dynein localization shows that loss of LET-99 and GPB-1 induces a similar movement defect which is independent of cortical dynein localization in the early C. elegans embryo.
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Affiliation(s)
- David P Ignacio
- Department of Molecular Genetics, Ohio State University, Columbus, Ohio, USA
| | - Natalia Kravtsova
- Department of Mathematics, Ohio State University, Columbus, Ohio, USA
| | - John Henry
- Department of Mathematics, Ohio State University, Columbus, Ohio, USA
| | | | - Adriana T Dawes
- Department of Mathematics, Department of Molecular Genetics, Ohio State University, Columbus, Ohio, USA
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Riparbelli MG, Persico V, Dallai R, Callaini G. Centrioles and Ciliary Structures during Male Gametogenesis in Hexapoda: Discovery of New Models. Cells 2020; 9:E744. [PMID: 32197383 PMCID: PMC7140630 DOI: 10.3390/cells9030744] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 03/08/2020] [Accepted: 03/10/2020] [Indexed: 12/12/2022] Open
Abstract
Centrioles are-widely conserved barrel-shaped organelles present in most organisms. They are indirectly involved in the organization of the cytoplasmic microtubules both in interphase and during the cell division by recruiting the molecules needed for microtubule nucleation. Moreover, the centrioles are required to assemble cilia and flagella by the direct elongation of their microtubule wall. Due to the importance of the cytoplasmic microtubules in several aspects of the cell life, any defect in centriole structure can lead to cell abnormalities that in humans may result in significant diseases. Many aspects of the centriole dynamics and function have been clarified in the last years, but little attention has been paid to the exceptions in centriole structure that occasionally appeared within the animal kingdom. Here, we focused our attention on non-canonical aspects of centriole architecture within the Hexapoda. The Hexapoda is one of the major animal groups and represents a good laboratory in which to examine the evolution and the organization of the centrioles. Although these findings represent obvious exceptions to the established rules of centriole organization, they may contribute to advance our understanding of the formation and the function of these organelles.
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Affiliation(s)
- Maria Giovanna Riparbelli
- Department of Life Sciences, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; (M.G.R.); (V.P.); (R.D.)
| | - Veronica Persico
- Department of Life Sciences, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; (M.G.R.); (V.P.); (R.D.)
| | - Romano Dallai
- Department of Life Sciences, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; (M.G.R.); (V.P.); (R.D.)
| | - Giuliano Callaini
- Department of Life Sciences, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; (M.G.R.); (V.P.); (R.D.)
- Department of Medical Biotechnologies, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy
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Andorfer R, Alper JD. From isolated structures to continuous networks: A categorization of cytoskeleton-based motile engineered biological microstructures. WILEY INTERDISCIPLINARY REVIEWS. NANOMEDICINE AND NANOBIOTECHNOLOGY 2019; 11:e1553. [PMID: 30740918 PMCID: PMC6881777 DOI: 10.1002/wnan.1553] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 12/27/2018] [Accepted: 12/28/2018] [Indexed: 11/06/2022]
Abstract
As technology at the small scale is advancing, motile engineered microstructures are becoming useful in drug delivery, biomedicine, and lab-on-a-chip devices. However, traditional engineering methods and materials can be inefficient or functionally inadequate for small-scale applications. Increasingly, researchers are turning to the biology of the cytoskeleton, including microtubules, actin filaments, kinesins, dyneins, myosins, and associated proteins, for both inspiration and solutions. They are engineering structures with components that range from being entirely biological to being entirely synthetic mimics of biology and on scales that range from isotropic continuous networks to single isolated structures. Motile biological microstructures trace their origins from the development of assays used to study the cytoskeleton to the array of structures currently available today. We define 12 types of motile biological microstructures, based on four categories: entirely biological, modular, hybrid, and synthetic, and three scales: networks, clusters, and isolated structures. We highlight some key examples, the unique functionalities, and the potential applications of each microstructure type, and we summarize the quantitative models that enable engineering them. By categorizing the diversity of motile biological microstructures in this way, we aim to establish a framework to classify these structures, define the gaps in current research, and spur ideas to fill those gaps. This article is categorized under: Nanotechnology Approaches to Biology > Nanoscale Systems in Biology Nanotechnology Approaches to Biology > Cells at the Nanoscale Biology-Inspired Nanomaterials > Protein and Virus-Based Structures Therapeutic Approaches and Drug Discovery > Emerging Technologies.
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Affiliation(s)
- Rachel Andorfer
- Department of Bioengineering, Clemson University, Clemson, South Carolina
- Department of Physics and Astronomy, Clemson University, Clemson, South Carolina
| | - Joshua D. Alper
- Department of Physics and Astronomy, Clemson University, Clemson, South Carolina
- Department of Biological Sciences, Clemson University, Clemson, South Carolina
- Eukaryotic Pathogen Innovations Center, Clemson University, Clemson, South Carolina
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Characterization of Novel Murine and Human PDAC Cell Models: Identifying the Role of Intestine Specific Homeobox Gene ISX in Hypoxia and Disease Progression. Transl Oncol 2019; 12:1056-1071. [PMID: 31174057 PMCID: PMC6556561 DOI: 10.1016/j.tranon.2019.05.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 05/03/2019] [Accepted: 05/03/2019] [Indexed: 11/23/2022] Open
Abstract
Therapy failure and metastasis-associated mortality are stumbling blocks in the management of PDAC in patients. Failure of therapy is associated to intense hypoxic conditions of tumors. To develop effective therapies, a complete understanding of hypoxia-associated changes in genetic landscape of tumors during disease progression is needed. Because artificially immortalized cell lines do not rightly represent the disease progression, studying genetics of tumors in spontaneous models is warranted. In the current study, we generated a spectrum of spontaneous human (UM-PDC1; UM-PDC2) and murine (HI-PanL, HI-PancI, HI-PanM) models representing localized, invasive, and metastatic PDAC from a patient and transgenic mice (K-rasG12D/Pdxcre/Ink4a/p16-/). These spontaneous models grow vigorously under hypoxia and exhibit activated K-ras signaling, progressive loss of PTEN, and tumorigenicity in vivo. Whereas UM-PDC1 form localized tumors, the UM-PDC2 metastasize to lungs in mice. In an order of progression, these models exhibit genomic instability marked by gross chromosomal rearrangements, centrosome-number variations, Aurora-kinase/H2AX colocalization, loss of primary cilia, and α-tubulin acetylation. The RNA sequencing of hypoxic models followed by qRT-PCR validation and gene-set enrichment identified Intestine-Specific Homeobox factor (ISX)–driven molecular pathway as an indicator PDAC aggressivness. TCGA-PAAD clinical data analysis showed high ISX expression correlation to poor survival of PDAC patients, particularly women. The functional studies showed ISX as a regulator of i) invasiveness and migratory potential and ii) VEGF, MMP2, and NFκB activation in PDAC cells. We suggest that ISX is a potential druggable target and newly developed spontaneous cell models are valuable tools for studying mechanism and testing therapies for PDAC.
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The effect and mechanism of millepachine-disrupted spindle assembly in tumor cells. Anticancer Drugs 2019; 29:449-456. [PMID: 29649038 DOI: 10.1097/cad.0000000000000618] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Millepachine (MIL) is a bioactive natural product that shows great potential for cancer treatment. Previous studies showed that MIL was a novel cancer drug candidate with a special structure. To provide reference for the research and development of MIL, we further investigated the mechanism of MIL inducing G2/M arrest and found MIL disrupted spindle assembly in tumor cells. In this study, we investigated the disrupting spindle assembly effects of MIL with a focus on its potential mechanism of action. First, we indicated that MIL did not inhibit microtubule polymerization from the results of in-vivo microtubule nucleation assay and microtubule polymerization in-vitro assay but delayed this process by inhibiting the production of ATP in tumor cells. Thereafter, we investigated the effect of MIL on the mitotic spindle. We found that MIL induced multipolar spindles by inhibiting the activity of Eg5 and inhibited mitotic spindle formation and chromatin condensation by the activation of the spindle assembly checkpoint (SAC) in tumor cells. These results established a novel function of MIL in regulating the assembly of mitotic spindle. As Eg5 and SAC are antitumor targets, effect of MIL on the Eg5 protein and SAC activation hinted that MIL has novel application in the development of antitumor drugs.
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9
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Avidor-Reiss T, Fishman EL. It takes two (centrioles) to tango. Reproduction 2019; 157:R33-R51. [PMID: 30496124 PMCID: PMC6494718 DOI: 10.1530/rep-18-0350] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Accepted: 11/29/2018] [Indexed: 12/11/2022]
Abstract
Cells that divide during embryo development require precisely two centrioles during interphase and four centrioles during mitosis. This precise number is maintained by allowing each centriole to nucleate only one centriole per cell cycle (i.e. centriole duplication). Yet, how the first cell of the embryo, the zygote, obtains two centrioles has remained a mystery in most mammals and insects. The mystery arose because the female gamete (oocyte) is thought to have no functional centrioles and the male gamete (spermatozoon) is thought to have only one functional centriole, resulting in a zygote with a single centriole. However, recent studies in fruit flies, beetles and mammals, including humans, suggest an alternative explanation: spermatozoa have a typical centriole and an atypical centriole. The sperm typical centriole has a normal structure but distinct protein composition, whereas the sperm atypical centriole is distinct in both. During fertilization, the atypical centriole is released into the zygote, nucleates a new centriole and participates in spindle pole formation. Thus, the spermatozoa's atypical centriole acts as a second centriole in the zygote. Here, we review centriole biology in general and especially in reproduction, we describe the discovery of the spermatozoon atypical centriole, and we provide an updated model for centriole inherence during sexual reproduction. While we focus on humans and other non-rodent mammals, we also provide a broader evolutionary perspective.
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Affiliation(s)
- Tomer Avidor-Reiss
- Department of Biological Sciences, University of Toledo, 2801 W. Bancroft Rd., Wolfe Hall 4259, Toledo, OH 43606
| | - Emily L. Fishman
- Department of Biological Sciences, University of Toledo, 2801 W. Bancroft Rd., Wolfe Hall 4259, Toledo, OH 43606
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10
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Kriegel AJ, Terhune SS, Greene AS, Noon KR, Pereckas MS, Liang M. Isomer-specific effect of microRNA miR-29b on nuclear morphology. J Biol Chem 2018; 293:14080-14088. [PMID: 30006350 DOI: 10.1074/jbc.ra117.001705] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Revised: 07/02/2018] [Indexed: 12/31/2022] Open
Abstract
Targeting mRNAs via seed region pairing is the canonical mechanism by which microRNAs (miRNAs) regulate cellular functions and disease processes. Emerging evidence suggests miRNAs might also act through other mechanisms. miRNA isomers that contain identical seed region sequences, such as miR-29a and miR-29b, provide naturally occurring, informative models for identifying those miRNA effects that are independent of seed region pairing. miR-29a and miR-29b are both expressed in HeLa cells, and miR-29b has been reported to localize to the nucleus in early mitosis because of unique nucleotide sequences on its 3' end. Here, we sought to better understand the mechanism of miR-29b nuclear localization and its function in cell division. We hypothesized that its nuclear localization may be facilitated by protein-miRNA interactions unique to miR-29b. Specific blockade of miR-29b resulted in striking nuclear irregularities not observed following miR-29a blockade. We also observed that miR-29b, but not miR-29a, is enriched in the nucleus and perinuclear clusters during mitosis. Targeted proteomic analysis of affinity-purified samples identified several proteins interacting with synthetic oligonucleotides mimicking miR-29b, but these proteins did not interact with miR-29a. One of these proteins, ADP/ATP translocase 2 (ANT2), known to be involved in mitotic spindle formation, colocalized with miR-29b in perinuclear clusters independently of Argonaute 2. Of note, ANT2 knockdown resulted in nuclear irregularities similar to those observed following miR-29b blockade and prevented nuclear uptake of endogenous miR-29b. Our findings reveal that miR-29 regulates nuclear morphology during mitosis and that this critical function is unique to the miR-29b isoform.
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Affiliation(s)
- Alison J Kriegel
- From the Department of Physiology, Center of Systems Molecular Medicine,
| | - Scott S Terhune
- the Department of Microbiology and Molecular Genetics, and.,the Biotechnology and Bioengineering Center, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Andrew S Greene
- From the Department of Physiology, Center of Systems Molecular Medicine.,the Biotechnology and Bioengineering Center, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Kathleen R Noon
- the Biotechnology and Bioengineering Center, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Michael S Pereckas
- the Biotechnology and Bioengineering Center, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Mingyu Liang
- From the Department of Physiology, Center of Systems Molecular Medicine,
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11
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Animal Female Meiosis: The Challenges of Eliminating Centrosomes. Cells 2018; 7:cells7070073. [PMID: 29996518 PMCID: PMC6071224 DOI: 10.3390/cells7070073] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 07/03/2018] [Accepted: 07/03/2018] [Indexed: 01/02/2023] Open
Abstract
Sexual reproduction requires the generation of gametes, which are highly specialised for fertilisation. Female reproductive cells, oocytes, grow up to large sizes when they accumulate energy stocks and store proteins as well as mRNAs to enable rapid cell divisions after fertilisation. At the same time, metazoan oocytes eliminate their centrosomes, i.e., major microtubule-organizing centres (MTOCs), during or right after the long growth phases. Centrosome elimination poses two key questions: first, how can the centrosome be re-established after fertilisation? In general, metazoan oocytes exploit sperm components, i.e., the basal body of the sperm flagellum, as a platform to reinitiate centrosome production. Second, how do most metazoan oocytes manage to build up meiotic spindles without centrosomes? Oocytes have evolved mechanisms to assemble bipolar spindles solely around their chromosomes without the guidance of pre-formed MTOCs. Female animal meiosis involves microtubule nucleation and organisation into bipolar microtubule arrays in regulated self-assembly under the control of the Ran system and nuclear transport receptors. This review summarises our current understanding of the molecular mechanism underlying self-assembly of meiotic spindles, its spatio-temporal regulation, and the key players governing this process in animal oocytes.
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12
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Chen D, Ito S, Hyodo T, Asano-Inami E, Yuan H, Senga T. Phosphorylation of DEPDC1 at Ser110 is required to maintain centrosome organization during mitosis. Exp Cell Res 2017; 358:101-110. [DOI: 10.1016/j.yexcr.2017.06.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 05/25/2017] [Accepted: 06/07/2017] [Indexed: 11/15/2022]
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13
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Galdos FX, Guo Y, Paige SL, VanDusen NJ, Wu SM, Pu WT. Cardiac Regeneration: Lessons From Development. Circ Res 2017; 120:941-959. [PMID: 28302741 DOI: 10.1161/circresaha.116.309040] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Revised: 12/14/2016] [Accepted: 12/15/2016] [Indexed: 02/06/2023]
Abstract
Palliative surgery for congenital heart disease has allowed patients with previously lethal heart malformations to survive and, in most cases, to thrive. However, these procedures often place pressure and volume loads on the heart, and over time, these chronic loads can cause heart failure. Current therapeutic options for initial surgery and chronic heart failure that results from failed palliation are limited, in part, by the mammalian heart's low inherent capacity to form new cardiomyocytes. Surmounting the heart regeneration barrier would transform the treatment of congenital, as well as acquired, heart disease and likewise would enable development of personalized, in vitro cardiac disease models. Although these remain distant goals, studies of heart development are illuminating the path forward and suggest unique opportunities for heart regeneration, particularly in fetal and neonatal periods. Here, we review major lessons from heart development that inform current and future studies directed at enhancing cardiac regeneration.
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Affiliation(s)
- Francisco X Galdos
- From the Cardiovascular Institute, School of Medicine, Stanford University, CA (F.X.G., S.L.P., S.M.W.); Department of Cardiology, Boston Children's Hospital, MA (Y.G., N.J.V., W.T.P.); Division of Pediatric Cardiology, Department of Pediatrics (S.L.P.), Division of Cardiovascular Medicine, Department of Medicine (S.M.W.), and Institute of Stem Cell and Regenerative Biology, School of Medicine, Stanford, CA (F.X.G., S.L.P., S.M.W.); and Harvard Stem Cell Institute, Harvard University, Cambridge, MA (W.T.P.)
| | - Yuxuan Guo
- From the Cardiovascular Institute, School of Medicine, Stanford University, CA (F.X.G., S.L.P., S.M.W.); Department of Cardiology, Boston Children's Hospital, MA (Y.G., N.J.V., W.T.P.); Division of Pediatric Cardiology, Department of Pediatrics (S.L.P.), Division of Cardiovascular Medicine, Department of Medicine (S.M.W.), and Institute of Stem Cell and Regenerative Biology, School of Medicine, Stanford, CA (F.X.G., S.L.P., S.M.W.); and Harvard Stem Cell Institute, Harvard University, Cambridge, MA (W.T.P.)
| | - Sharon L Paige
- From the Cardiovascular Institute, School of Medicine, Stanford University, CA (F.X.G., S.L.P., S.M.W.); Department of Cardiology, Boston Children's Hospital, MA (Y.G., N.J.V., W.T.P.); Division of Pediatric Cardiology, Department of Pediatrics (S.L.P.), Division of Cardiovascular Medicine, Department of Medicine (S.M.W.), and Institute of Stem Cell and Regenerative Biology, School of Medicine, Stanford, CA (F.X.G., S.L.P., S.M.W.); and Harvard Stem Cell Institute, Harvard University, Cambridge, MA (W.T.P.)
| | - Nathan J VanDusen
- From the Cardiovascular Institute, School of Medicine, Stanford University, CA (F.X.G., S.L.P., S.M.W.); Department of Cardiology, Boston Children's Hospital, MA (Y.G., N.J.V., W.T.P.); Division of Pediatric Cardiology, Department of Pediatrics (S.L.P.), Division of Cardiovascular Medicine, Department of Medicine (S.M.W.), and Institute of Stem Cell and Regenerative Biology, School of Medicine, Stanford, CA (F.X.G., S.L.P., S.M.W.); and Harvard Stem Cell Institute, Harvard University, Cambridge, MA (W.T.P.)
| | - Sean M Wu
- From the Cardiovascular Institute, School of Medicine, Stanford University, CA (F.X.G., S.L.P., S.M.W.); Department of Cardiology, Boston Children's Hospital, MA (Y.G., N.J.V., W.T.P.); Division of Pediatric Cardiology, Department of Pediatrics (S.L.P.), Division of Cardiovascular Medicine, Department of Medicine (S.M.W.), and Institute of Stem Cell and Regenerative Biology, School of Medicine, Stanford, CA (F.X.G., S.L.P., S.M.W.); and Harvard Stem Cell Institute, Harvard University, Cambridge, MA (W.T.P.).
| | - William T Pu
- From the Cardiovascular Institute, School of Medicine, Stanford University, CA (F.X.G., S.L.P., S.M.W.); Department of Cardiology, Boston Children's Hospital, MA (Y.G., N.J.V., W.T.P.); Division of Pediatric Cardiology, Department of Pediatrics (S.L.P.), Division of Cardiovascular Medicine, Department of Medicine (S.M.W.), and Institute of Stem Cell and Regenerative Biology, School of Medicine, Stanford, CA (F.X.G., S.L.P., S.M.W.); and Harvard Stem Cell Institute, Harvard University, Cambridge, MA (W.T.P.).
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14
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Riparbelli MG, Gottardo M, Callaini G. Parthenogenesis in Insects: The Centriole Renaissance. Results Probl Cell Differ 2017; 63:435-479. [PMID: 28779329 DOI: 10.1007/978-3-319-60855-6_19] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Building a new organism usually requires the contribution of two differently shaped haploid cells, the male and female gametes, each providing its genetic material to restore diploidy of the new born zygote. The successful execution of this process requires defined sequential steps that must be completed in space and time. Otherwise, development fails. Relevant among the earlier steps are pronuclear migration and formation of the first mitotic spindle that promote the mixing of parental chromosomes and the formation of the zygotic nucleus. A complex microtubule network ensures the proper execution of these processes. Instrumental to microtubule organization and bipolar spindle assembly is a distinct non-membranous organelle, the centrosome. Centrosome inheritance during fertilization is biparental, since both gametes provide essential components to build a functional centrosome. This model does not explain, however, centrosome formation during parthenogenetic development, a special mode of sexual reproduction in which the unfertilized egg develops without the contribution of the male gamete. Moreover, whereas fertilization is a relevant example in which the cells actively check the presence of only one centrosome, to avoid multipolar spindle formation, the development of parthenogenetic eggs is ensured, at least in insects, by the de novo assembly of multiple centrosomes.Here, we will focus our attention on the assembly of functional centrosomes following fertilization and during parthenogenetic development in insects. Parthenogenetic development in which unfertilized eggs are naturally depleted of centrosomes would provide a useful experimental system to investigate centriole assembly and duplication together with centrosome formation and maturation.
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Affiliation(s)
| | - Marco Gottardo
- Department of Life Sciences, University of Siena, Via A. Moro 2, 53100, Siena, Italy
| | - Giuliano Callaini
- Department of Life Sciences, University of Siena, Via A. Moro 2, 53100, Siena, Italy.
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15
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Abstract
Centrosome amplification is a common feature of both solid and hematological human malignancies. Extra centrosomes are not merely innocent bystanders in cancer cells, but rather promote tumor progression by disrupting normal cellular architecture and generating chromosome instability. Consequently, centrosome amplification correlates with advanced tumor grade and overall poor clinical prognosis. By contrast, extra centrosomes are adversely tolerated in non-transformed cells and hinder cell proliferation. This suggests that in addition to acquiring extra centrosomes, cancer cells must also adapt to overcome the deleterious consequences associated with them. Here, we review evidence that implicates core components of the Hippo tumor suppressor pathway as having key roles in both the direct and indirect regulation of centrosome number. Intriguingly, functional inactivation of the Hippo pathway, which is common across broad spectrum of human cancers, likely represents one key adaptation that enables cancer cells to tolerate extra centrosomes.
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16
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Al-Obaidi N, Mitchison TJ, Crews CM, Mayer TU. Identification of MAC1: A Small Molecule That Rescues Spindle Bipolarity in Monastrol-Treated Cells. ACS Chem Biol 2016; 11:1544-51. [PMID: 27121275 DOI: 10.1021/acschembio.6b00203] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The genetic integrity of each organism is intimately tied to the correct segregation of its genome during mitosis. Insights into the underlying mechanisms are fundamental for both basic research and the development of novel strategies to treat mitosis-relevant diseases such as cancer. Due to their fast mode of action, small molecules are invaluable tools to dissect mitosis. Yet, there is a great demand for novel antimitotic compounds. We performed a chemical genetic suppression screen to identify compounds that restore spindle bipolarity in cells treated with Monastrol, an inhibitor of the mitotic kinesin Eg5. We identified one compound-MAC1-that rescued spindle bipolarity in cells lacking Eg5 activity. Mechanistically, MAC1 induces the formation of additional microtubule nucleation centers, which allows kinesin Kif15-dependent bipolar spindle assembly in the absence of Eg5 activity. Thus, our chemical genetic suppression screen revealed novel unexpected insights into the mechanism of spindle assembly in mammalian cells.
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Affiliation(s)
- Naowras Al-Obaidi
- Department
of Biology and Konstanz Research School Chemical-Biology (KoRS-CB), University of Konstanz, Universitätsstr. 10, 78467 Konstanz, Germany
| | - Timothy J. Mitchison
- Department
of Systems Biology, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Craig M. Crews
- Departments
of Molecular, Cellular, and Developmental Biology, Chemistry, and
Pharmacology, Yale University, 219 Prospect St., New Haven, Connecticut, United States
| | - Thomas U. Mayer
- Department
of Biology and Konstanz Research School Chemical-Biology (KoRS-CB), University of Konstanz, Universitätsstr. 10, 78467 Konstanz, Germany
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17
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Chromosome missegregation during anaphase triggers p53 cell cycle arrest through histone H3.3 Ser31 phosphorylation. Nat Cell Biol 2016; 18:668-75. [DOI: 10.1038/ncb3348] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Accepted: 03/29/2016] [Indexed: 12/12/2022]
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18
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D'Assoro AB, Haddad T, Galanis E. Aurora-A Kinase as a Promising Therapeutic Target in Cancer. Front Oncol 2016; 5:295. [PMID: 26779440 PMCID: PMC4701905 DOI: 10.3389/fonc.2015.00295] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Accepted: 12/11/2015] [Indexed: 12/14/2022] Open
Abstract
Mammalian Aurora family of serine/threonine kinases are master regulators of mitotic progression and are frequently overexpressed in human cancers. Among the three members of the Aurora kinase family (Aurora-A, -B, and -C), Aurora-A and Aurora-B are expressed at detectable levels in somatic cells undergoing mitotic cell division. Aberrant Aurora-A kinase activity has been implicated in oncogenic transformation through the development of chromosomal instability and tumor cell heterogeneity. Recent studies also reveal a novel non-mitotic role of Aurora-A activity in promoting tumor progression through activation of epithelial-mesenchymal transition reprograming resulting in the genesis of tumor-initiating cells. Therefore, Aurora-A kinase represents an attractive target for cancer therapeutics, and the development of small molecule inhibitors of Aurora-A oncogenic activity may improve the clinical outcomes of cancer patients. In the present review, we will discuss mitotic and non-mitotic functions of Aurora-A activity in oncogenic transformation and tumor progression. We will also review the current clinical studies, evaluating small molecule inhibitors of Aurora-A activity and their efficacy in the management of cancer patients.
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Affiliation(s)
- Antonino B D'Assoro
- Department of Medical Oncology, Mayo Clinic College of Medicine, Rochester, MN, USA; Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Tufia Haddad
- Department of Medical Oncology, Mayo Clinic College of Medicine , Rochester, MN , USA
| | - Evanthia Galanis
- Department of Medical Oncology, Mayo Clinic College of Medicine, Rochester, MN, USA; Department of Molecular Medicine, Mayo Clinic College of Medicine, Rochester, MN, USA
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19
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Vacchelli E, Aranda F, Bloy N, Buqué A, Cremer I, Eggermont A, Fridman WH, Fucikova J, Galon J, Spisek R, Zitvogel L, Kroemer G, Galluzzi L. Trial Watch-Immunostimulation with cytokines in cancer therapy. Oncoimmunology 2015; 5:e1115942. [PMID: 27057468 DOI: 10.1080/2162402x.2015.1115942] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Accepted: 10/29/2015] [Indexed: 02/07/2023] Open
Abstract
During the past decade, great efforts have been dedicated to the development of clinically relevant interventions that would trigger potent (and hence potentially curative) anticancer immune responses. Indeed, developing neoplasms normally establish local and systemic immunosuppressive networks that inhibit tumor-targeting immune effector cells, be them natural or elicited by (immuno)therapy. One possible approach to boost anticancer immunity consists in the (generally systemic) administration of recombinant immunostimulatory cytokines. In a limited number of oncological indications, immunostimulatory cytokines mediate clinical activity as standalone immunotherapeutic interventions. Most often, however, immunostimulatory cytokines are employed as immunological adjuvants, i.e., to unleash the immunogenic potential of other immunotherapeutic agents, like tumor-targeting vaccines and checkpoint blockers. Here, we discuss recent preclinical and clinical advances in the use of some cytokines as immunostimulatory agents in oncological indications.
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Affiliation(s)
- Erika Vacchelli
- INSERM, U1138, Paris, France; Université Paris Descartes/Paris V, Sorbonne Paris Cité, Paris, France; Université Pierre et Marie Curie/Paris VI, Paris, France; Equipe 11 labellisée par la Ligue Nationale contre le Cancer, Center de Recherche des Cordeliers, Paris, France; Gustave Roussy Cancer Campus, Villejuif, France
| | - Fernando Aranda
- Group of Immune receptors of the Innate and Adaptive System, Institut d'Investigacions Biomédiques August Pi i Sunyer (IDIBAPS)
| | - Norma Bloy
- INSERM, U1138, Paris, France; Université Paris Descartes/Paris V, Sorbonne Paris Cité, Paris, France; Université Pierre et Marie Curie/Paris VI, Paris, France; Equipe 11 labellisée par la Ligue Nationale contre le Cancer, Center de Recherche des Cordeliers, Paris, France; Gustave Roussy Cancer Campus, Villejuif, France
| | - Aitziber Buqué
- INSERM, U1138, Paris, France; Université Paris Descartes/Paris V, Sorbonne Paris Cité, Paris, France; Université Pierre et Marie Curie/Paris VI, Paris, France; Equipe 11 labellisée par la Ligue Nationale contre le Cancer, Center de Recherche des Cordeliers, Paris, France; Gustave Roussy Cancer Campus, Villejuif, France
| | - Isabelle Cremer
- INSERM, U1138, Paris, France; Université Paris Descartes/Paris V, Sorbonne Paris Cité, Paris, France; Université Pierre et Marie Curie/Paris VI, Paris, France; Equipe 13, Center de Recherche des Cordeliers, Paris, France
| | | | - Wolf Hervé Fridman
- INSERM, U1138, Paris, France; Université Paris Descartes/Paris V, Sorbonne Paris Cité, Paris, France; Université Pierre et Marie Curie/Paris VI, Paris, France; Equipe 13, Center de Recherche des Cordeliers, Paris, France
| | - Jitka Fucikova
- Sotio, Prague, Czech Republic; Dept. of Immunology, 2nd Faculty of Medicine and University Hospital Motol, Charles University, Prague, Czech Republic
| | - Jérôme Galon
- INSERM, U1138, Paris, France; Université Paris Descartes/Paris V, Sorbonne Paris Cité, Paris, France; Université Pierre et Marie Curie/Paris VI, Paris, France; Laboratory of Integrative Cancer Immunology, Center de Recherche des Cordeliers, Paris, France
| | - Radek Spisek
- Sotio, Prague, Czech Republic; Dept. of Immunology, 2nd Faculty of Medicine and University Hospital Motol, Charles University, Prague, Czech Republic
| | - Laurence Zitvogel
- Gustave Roussy Cancer Campus, Villejuif, France; INSERM, U1015, CICBT507, Villejuif, France
| | - Guido Kroemer
- INSERM, U1138, Paris, France; Université Paris Descartes/Paris V, Sorbonne Paris Cité, Paris, France; Université Pierre et Marie Curie/Paris VI, Paris, France; Equipe 11 labellisée par la Ligue Nationale contre le Cancer, Center de Recherche des Cordeliers, Paris, France; Pôle de Biologie, Hôpital Européen Georges Pompidou, AP-HP, Paris, France; Metabolomics and Cell Biology Platforms, Gustave Roussy Cancer Campus, Villejuif, France; Department of Women's and Children's Health, Karolinska University Hospital, Stockholm, Sweden
| | - Lorenzo Galluzzi
- INSERM, U1138, Paris, France; Université Paris Descartes/Paris V, Sorbonne Paris Cité, Paris, France; Université Pierre et Marie Curie/Paris VI, Paris, France; Equipe 11 labellisée par la Ligue Nationale contre le Cancer, Center de Recherche des Cordeliers, Paris, France; Gustave Roussy Cancer Campus, Villejuif, France
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20
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Wei H, Wang Q, DU J, Li X, Zhang N, Cao Y, Ma W. Unique subcellular distribution of RPB1 with a phosphorylated C-terminal domain (CTD) in mouse oocytes during meiotic division and its relationship with chromosome separation. J Reprod Dev 2015; 61:541-8. [PMID: 26346254 PMCID: PMC4685220 DOI: 10.1262/jrd.2015-051] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Polymerase (RNA) II (DNA directed) polypeptide A (RPB1) is the largest subunit of RNA polymerase II
(RNAPII), and phosphorylation of its C-terminal domain (CTD) is required for transcription initiation,
elongation and RNA processing. Little is known about the CTD phosphorylation pattern and potential function
during cell division when transcription is silenced. In this study, we assessed the protein expression and
subcellular distribution of RPB1 during mouse oocyte meiotic division. Western blot analysis revealed that the
RPB1 CTD was highly phosphorylated on Ser2 (pRPB1Ser2), Ser5 (pRPB1Ser5) and Ser7
(pRPB1Ser7). High and stable expression of pRPB1Ser2 and pRPB1Ser5 was
detected from germinal vesicle (GV) to Metaphase II (MII) stage. In contrast, pRPB1Ser7 only
emerged after germinal vesicle breakdown (GVBD) and gradually increased to its peak level at metaphase I (MI)
and MII. Immunofluorescence demonstrated that pRPB1Ser2, pRPB1Ser5 and
pRPB1Ser7 were pronouncedly aggregated within the nucleus of GV oocytes with a non-surrounded
nucleolus (NSN) but very faintly labeled in oocytes with a surrounded nucleolus (SN). After meiotic
resumption, pRPB1Ser2 was again detected at spindle poles and co-localized with key microtubule
organizing center (MTOC) components, pericentrin and γ-tubulin. pRPB1Ser5 and pRPB1Ser7
were assembled as filamentous aggregates and co-localized with microtubules throughout the spindle structure,
responding to spindle-disturbing drugs, nocodazole or taxol, in pattern strongly similar to microtubules.
pRPB1Ser2 and pRPB1Ser5 were constantly localized on chromosomes, with a relatively
high concentration in centromere areas. Taken together, our data suggest that the CTD is highly phosphorylated
and may be required for accurate chromosome segregation in mouse oocytes during meiosis.
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Affiliation(s)
- HaoJie Wei
- Department of Histology and Embryology, School of Basic Medical Sciences, Capital Medical University, Beijing 100069, China
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21
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Baumbach J, Novak ZA, Raff JW, Wainman A. Dissecting the function and assembly of acentriolar microtubule organizing centers in Drosophila cells in vivo. PLoS Genet 2015; 11:e1005261. [PMID: 26020779 PMCID: PMC4447278 DOI: 10.1371/journal.pgen.1005261] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Accepted: 05/04/2015] [Indexed: 11/18/2022] Open
Abstract
Acentriolar microtubule organizing centers (aMTOCs) are formed during meiosis and mitosis in several cell types, but their function and assembly mechanism is unclear. Importantly, aMTOCs can be overactive in cancer cells, enhancing multipolar spindle formation, merotelic kinetochore attachment and aneuploidy. Here we show that aMTOCs can form in acentriolar Drosophila somatic cells in vivo via an assembly pathway that depends on Asl, Cnn and, to a lesser extent, Spd-2--the same proteins that appear to drive mitotic centrosome assembly in flies. This finding enabled us to ablate aMTOC formation in acentriolar cells, and so perform a detailed genetic analysis of the contribution of aMTOCs to acentriolar mitotic spindle formation. Here we show that although aMTOCs can nucleate microtubules, they do not detectably increase the efficiency of acentriolar spindle assembly in somatic fly cells. We find that they are required, however, for robust microtubule array assembly in cells without centrioles that also lack microtubule nucleation from around the chromatin. Importantly, aMTOCs are also essential for dynein-dependent acentriolar spindle pole focusing and for robust cell proliferation in the absence of centrioles and HSET/Ncd (a kinesin essential for acentriolar spindle pole focusing in many systems). We propose an updated model for acentriolar spindle pole coalescence by the molecular motors Ncd/HSET and dynein in conjunction with aMTOCs.
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Affiliation(s)
- Janina Baumbach
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Zsofia Anna Novak
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Jordan W. Raff
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Alan Wainman
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
- * E-mail:
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