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Prozzillo Y, Fattorini G, Ferreri D, Leo M, Dimitri P, Messina G. Knockdown of DOM/Tip60 Complex Subunits Impairs Male Meiosis of Drosophila melanogaster. Cells 2023; 12:1348. [PMID: 37408183 DOI: 10.3390/cells12101348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 04/22/2023] [Accepted: 05/02/2023] [Indexed: 07/07/2023] Open
Abstract
ATP-dependent chromatin remodeling complexes are involved in nucleosome sliding and eviction and/or the incorporation of histone variants into chromatin to facilitate several cellular and biological processes, including DNA transcription, replication and repair. The DOM/TIP60 chromatin remodeling complex of Drosophila melanogaster contains 18 subunits, including the DOMINO (DOM), an ATPase that catalyzes the exchange of the canonical H2A with its variant (H2A.V), and TIP60, a lysine-acetyltransferase that acetylates H4, H2A and H2A.V histones. In recent decades, experimental evidence has shown that ATP-dependent chromatin remodeling factors, in addition to their role in chromatin organization, have a functional relevance in cell division. In particular, emerging studies suggested the direct roles of ATP-dependent chromatin remodeling complex subunits in controlling mitosis and cytokinesis in both humans and D. melanogaster. However, little is known about their possible involvement during meiosis. The results of this work show that the knockdown of 12 of DOM/TIP60 complex subunits generates cell division defects that, in turn, cause total/partial sterility in Drosophila males, providing new insights into the functions of chromatin remodelers in cell division control during gametogenesis.
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Affiliation(s)
- Yuri Prozzillo
- Department of Biology and Biotechnology "Charles Darwin", Sapienza University of Rome, 00185 Rome, Italy
| | - Gaia Fattorini
- Department of Biology and Biotechnology "Charles Darwin", Sapienza University of Rome, 00185 Rome, Italy
- Institute of Molecular Biology and Pathology (IBPM), Consiglio Nazionale delle Ricerche (CNR), Sapienza University of Rome, 00185 Rome, Italy
| | - Diego Ferreri
- Department of Biology and Biotechnology "Charles Darwin", Sapienza University of Rome, 00185 Rome, Italy
| | - Manuela Leo
- Department of Sciences and Technologies, University of Sannio, 82100 Benevento, Italy
| | - Patrizio Dimitri
- Department of Biology and Biotechnology "Charles Darwin", Sapienza University of Rome, 00185 Rome, Italy
| | - Giovanni Messina
- Department of Biology and Biotechnology "Charles Darwin", Sapienza University of Rome, 00185 Rome, Italy
- Pasteur Institute, Fondazione Cenci-Bolognetti, 00161 Rome, Italy
- Department of Biotechnology and Biosciences, Milano-Bicocca University, 20126 Milan, Italy
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2
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Kasinathan B, Colmenares SU, McConnell H, Young JM, Karpen GH, Malik HS. Innovation of heterochromatin functions drives rapid evolution of essential ZAD-ZNF genes in Drosophila. eLife 2020; 9:e63368. [PMID: 33169670 PMCID: PMC7655104 DOI: 10.7554/elife.63368] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 10/12/2020] [Indexed: 12/12/2022] Open
Abstract
Contrary to dogma, evolutionarily young and dynamic genes can encode essential functions. We find that evolutionarily dynamic ZAD-ZNF genes, which encode the most abundant class of insect transcription factors, are more likely to encode essential functions in Drosophila melanogaster than ancient, conserved ZAD-ZNF genes. We focus on the Nicknack ZAD-ZNF gene, which is evolutionarily young, poorly retained in Drosophila species, and evolves under strong positive selection. Yet we find that it is necessary for larval development in D. melanogaster. We show that Nicknack encodes a heterochromatin-localizing protein like its paralog Oddjob, also an evolutionarily dynamic yet essential ZAD-ZNF gene. We find that the divergent D. simulans Nicknack protein can still localize to D. melanogaster heterochromatin and rescue viability of female but not male Nicknack-null D. melanogaster. Our findings suggest that innovation for rapidly changing heterochromatin functions might generally explain the essentiality of many evolutionarily dynamic ZAD-ZNF genes in insects.
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Affiliation(s)
- Bhavatharini Kasinathan
- Medical Scientist Training Program, University of Washington School of MedicineSeattleUnited States
- Molecular and Cellular Biology Graduate program, University of Washington School of MedicineSeattleUnited States
- Division of Basic Sciences, Fred Hutchinson Cancer Research CenterSeattleUnited States
| | - Serafin U Colmenares
- Biological Systems and Engineering Division, Lawrence Berkeley National LaboratoryBerkeleyUnited States
- Department of Molecular and Cell Biology, University of California at BerkeleyBerkeleyUnited States
- Innovative Genomics InstituteBerkeleyUnited States
| | - Hannah McConnell
- Division of Basic Sciences, Fred Hutchinson Cancer Research CenterSeattleUnited States
| | - Janet M Young
- Division of Basic Sciences, Fred Hutchinson Cancer Research CenterSeattleUnited States
| | - Gary H Karpen
- Biological Systems and Engineering Division, Lawrence Berkeley National LaboratoryBerkeleyUnited States
- Department of Molecular and Cell Biology, University of California at BerkeleyBerkeleyUnited States
- Innovative Genomics InstituteBerkeleyUnited States
| | - Harmit S Malik
- Division of Basic Sciences, Fred Hutchinson Cancer Research CenterSeattleUnited States
- Howard Hughes Medical Institute, Fred Hutchinson Cancer Research CenterSeattleUnited States
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3
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Ferrand J, Rondinelli B, Polo SE. Histone Variants: Guardians of Genome Integrity. Cells 2020; 9:E2424. [PMID: 33167489 PMCID: PMC7694513 DOI: 10.3390/cells9112424] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 10/30/2020] [Accepted: 11/03/2020] [Indexed: 12/12/2022] Open
Abstract
Chromatin integrity is key for cell homeostasis and for preventing pathological development. Alterations in core chromatin components, histone proteins, recently came into the spotlight through the discovery of their driving role in cancer. Building on these findings, in this review, we discuss how histone variants and their associated chaperones safeguard genome stability and protect against tumorigenesis. Accumulating evidence supports the contribution of histone variants and their chaperones to the maintenance of chromosomal integrity and to various steps of the DNA damage response, including damaged chromatin dynamics, DNA damage repair, and damage-dependent transcription regulation. We present our current knowledge on these topics and review recent advances in deciphering how alterations in histone variant sequence, expression, and deposition into chromatin fuel oncogenic transformation by impacting cell proliferation and cell fate transitions. We also highlight open questions and upcoming challenges in this rapidly growing field.
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Affiliation(s)
| | | | - Sophie E. Polo
- Epigenetics & Cell Fate Centre, UMR7216 CNRS, Université de Paris, 75013 Paris, France; (J.F.); (B.R.)
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4
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Martire S, Banaszynski LA. The roles of histone variants in fine-tuning chromatin organization and function. Nat Rev Mol Cell Biol 2020; 21:522-541. [PMID: 32665685 PMCID: PMC8245300 DOI: 10.1038/s41580-020-0262-8] [Citation(s) in RCA: 194] [Impact Index Per Article: 48.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/28/2020] [Indexed: 12/15/2022]
Abstract
Histones serve to both package and organize DNA within the nucleus. In addition to histone post-translational modification and chromatin remodelling complexes, histone variants contribute to the complexity of epigenetic regulation of the genome. Histone variants are characterized by a distinct protein sequence and a selection of designated chaperone systems and chromatin remodelling complexes that regulate their localization in the genome. In addition, histone variants can be enriched with specific post-translational modifications, which in turn can provide a scaffold for recruitment of variant-specific interacting proteins to chromatin. Thus, through these properties, histone variants have the capacity to endow specific regions of chromatin with unique character and function in a regulated manner. In this Review, we provide an overview of recent advances in our understanding of the contribution of histone variants to chromatin function in mammalian systems. First, we discuss new molecular insights into chaperone-mediated histone variant deposition. Next, we discuss mechanisms by which histone variants influence chromatin properties such as nucleosome stability and the local chromatin environment both through histone variant sequence-specific effects and through their role in recruiting different chromatin-associated complexes. Finally, we focus on histone variant function in the context of both embryonic development and human disease, specifically developmental syndromes and cancer.
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Affiliation(s)
- Sara Martire
- Green Center for Reproductive Biology Sciences, Department of Obstetrics and Gynecology, Children's Research Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Laura A Banaszynski
- Green Center for Reproductive Biology Sciences, Department of Obstetrics and Gynecology, Children's Research Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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5
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Meyer-Nava S, Nieto-Caballero VE, Zurita M, Valadez-Graham V. Insights into HP1a-Chromatin Interactions. Cells 2020; 9:E1866. [PMID: 32784937 PMCID: PMC7465937 DOI: 10.3390/cells9081866] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 07/18/2020] [Accepted: 07/21/2020] [Indexed: 12/17/2022] Open
Abstract
Understanding the packaging of DNA into chromatin has become a crucial aspect in the study of gene regulatory mechanisms. Heterochromatin establishment and maintenance dynamics have emerged as some of the main features involved in genome stability, cellular development, and diseases. The most extensively studied heterochromatin protein is HP1a. This protein has two main domains, namely the chromoshadow and the chromodomain, separated by a hinge region. Over the years, several works have taken on the task of identifying HP1a partners using different strategies. In this review, we focus on describing these interactions and the possible complexes and subcomplexes associated with this critical protein. Characterization of these complexes will help us to clearly understand the implications of the interactions of HP1a in heterochromatin maintenance, heterochromatin dynamics, and heterochromatin's direct relationship to gene regulation and chromatin organization.
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Affiliation(s)
| | | | | | - Viviana Valadez-Graham
- Instituto de Biotecnología, Departamento de Genética del Desarrollo y Fisiología Molecular, Universidad Nacional Autónoma de México, Cuernavaca Morelos 62210, Mexico; (S.M.-N.); (V.E.N.-C.); (M.Z.)
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6
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Short Histone H2A Variants: Small in Stature but not in Function. Cells 2020; 9:cells9040867. [PMID: 32252453 PMCID: PMC7226823 DOI: 10.3390/cells9040867] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 03/24/2020] [Accepted: 03/31/2020] [Indexed: 12/19/2022] Open
Abstract
The dynamic packaging of DNA into chromatin regulates all aspects of genome function by altering the accessibility of DNA and by providing docking pads to proteins that copy, repair and express the genome. Different epigenetic-based mechanisms have been described that alter the way DNA is organised into chromatin, but one fundamental mechanism alters the biochemical composition of a nucleosome by substituting one or more of the core histones with their variant forms. Of the core histones, the largest number of histone variants belong to the H2A class. The most divergent class is the designated “short H2A variants” (H2A.B, H2A.L, H2A.P and H2A.Q), so termed because they lack a H2A C-terminal tail. These histone variants appeared late in evolution in eutherian mammals and are lineage-specific, being expressed in the testis (and, in the case of H2A.B, also in the brain). To date, most information about the function of these peculiar histone variants has come from studies on the H2A.B and H2A.L family in mice. In this review, we describe their unique protein characteristics, their impact on chromatin structure, and their known functions plus other possible, even non-chromatin, roles in an attempt to understand why these peculiar histone variants evolved in the first place.
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7
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Ryan DP, Tremethick DJ. The interplay between H2A.Z and H3K9 methylation in regulating HP1α binding to linker histone-containing chromatin. Nucleic Acids Res 2019; 46:9353-9366. [PMID: 30007360 PMCID: PMC6182156 DOI: 10.1093/nar/gky632] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 07/04/2018] [Indexed: 12/14/2022] Open
Abstract
One of the most intensively studied chromatin binding factors is HP1α. HP1α is associated with silenced, heterochromatic regions of the genome and binds to H3K9me3. While H3K9me3 is necessary for HP1α recruitment to heterochromatin, it is becoming apparent that it is not sufficient suggesting that additional factors are involved. One candidate proposed as a potential regulator of HP1α recruitment is the linker histone H1.4. Changes to the underlying make-up of chromatin, such as the incorporation of the histone variant H2A.Z, has also been linked with regulating HP1 binding to chromatin. Here, we rigorously dissected the effects of H1.4, H2A.Z and H3K9me3 on the nucleosome binding activity of HP1α in vitro employing arrays, mononucleosomes and nucleosome core particles. Unexpectedly, histone H1.4 impedes the binding of HP1α but strikingly, this inhibition is partially relieved by the incorporation of both H2A.Z and H3K9me3 but only in the context of arrays or nucleosome core particles. Our data suggests that there are two modes of interaction of HP1α with nucleosomes. The first primary mode is through interactions with linker DNA. However, when linker DNA is missing or occluded by linker histones, HP1α directly interacts with the nucleosome core and this interaction is enhanced by H2A.Z with H3K9me3.
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Affiliation(s)
- Daniel P Ryan
- Department of Genome Sciences, The John Curtin School of Medical Research, The Australian National University, ACT 2601, Australia
| | - David J Tremethick
- Department of Genome Sciences, The John Curtin School of Medical Research, The Australian National University, ACT 2601, Australia
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8
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Mascolo E, Amoroso N, Saggio I, Merigliano C, Vernì F. Pyridoxine/pyridoxamine 5'-phosphate oxidase (Sgll/PNPO) is important for DNA integrity and glucose homeostasis maintenance in Drosophila. J Cell Physiol 2019; 235:504-512. [PMID: 31506944 DOI: 10.1002/jcp.28990] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Accepted: 05/29/2019] [Indexed: 01/08/2023]
Abstract
Pyridoxine/pyridoxamine 5'-phosphate oxidase (PNPO) and pyridoxal kinase (PDXK) cooperate to produce pyridoxal 5'-phosphate (PLP), the active form of vitamin B6. PDXK phosphorylates pyridoxine, pyridoxamine, and pyridoxal by producing PNP, PMP, and PLP, whereas PNPO oxidizes PNP, PMP, into PLP. We previously demonstrated that PDXK depletion in Drosophila and human cells impacts on glucose metabolism and DNA integrity. Here we characterized sgll, the Drosophila ortholog of PNPO gene, showing that its silencing by RNA interference elicits chromosome aberrations (CABs) in brains and induces diabetic hallmarks such as hyperglycemia and small body size. We showed that in sgllRNAi neuroblasts CABs are largely produced by the genotoxic effect of the advanced glycation end products triggered by high glucose. As in sgllRNAi cells, part of PLP is still produced by PDXK activity, these data suggest that PLP dosage need to be tightly regulated to guarantee glucose homeostasis and DNA integrity.
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Affiliation(s)
- Elisa Mascolo
- Dipartimento di Biologia e Biotecnologie "C. Darwin,", Sapienza Università di Roma, Rome, Italy
| | - Noemi Amoroso
- Dipartimento di Biologia e Biotecnologie "C. Darwin,", Sapienza Università di Roma, Rome, Italy
| | - Isabella Saggio
- Dipartimento di Biologia e Biotecnologie "C. Darwin,", Sapienza Università di Roma, Rome, Italy.,School of Biological Science, Institute of Structural Biology, Nanyang Technological University, Singapore
| | - Chiara Merigliano
- Dipartimento di Biologia e Biotecnologie "C. Darwin,", Sapienza Università di Roma, Rome, Italy.,University of Southern California, Los Angeles, USA
| | - Fiammetta Vernì
- Dipartimento di Biologia e Biotecnologie "C. Darwin,", Sapienza Università di Roma, Rome, Italy
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9
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A new role for Drosophila Aurora-A in maintaining chromosome integrity. Chromosoma 2019; 128:41-52. [PMID: 30612150 DOI: 10.1007/s00412-018-00687-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 12/05/2018] [Accepted: 12/07/2018] [Indexed: 02/07/2023]
Abstract
Aurora-A is a conserved mitotic kinase overexpressed in many types of cancer. Growing evidence shows that Aurora-A plays a crucial role in DNA damage response (DDR) although this aspect has been less characterized. We isolated a new aur-A mutation, named aur-A949, in Drosophila, and we showed that it causes chromosome aberrations (CABs). In addition, aur-A949 mutants were sensitive to X-ray treatment and showed impaired γ-H2Av foci dissolution kinetics. To identify the pathway in which Aur-A works, we conducted an epistasis analysis by evaluating CAB frequencies in double mutants carrying aur-A949 mutation combined to mutations in genes related to DNA damage response (DDR). We found that mutations in tefu (ATM) and in the histone variant H2Av were epistatic over aur-A949 indicating that Aur-A works in DDR and that it is required for γ-H2Av foci dissolution. More interestingly, we found that a mutation in lig4, a gene belonging to the non-homologous end joining (NHEJ) repair pathway, was epistatic over aur-A949. Based on studies in other systems, which show that phosphorylation is important to target Lig4 for degradation, we hypothesized that in aur-A949 mutant cells, there is a persistence of Lig4 that could be, in the end, responsible for CABs. Finally, we observed a synergistic interaction between Aur-A and the homologous recombination (HR) repair system component Rad 51 in the process that converts chromatid deletions into isochromatid deletions. Altogether, these data indicate that Aur-A depletion can elicit chromosome damage. This conclusion should be taken into consideration, since some anticancer therapies are aimed at reducing Aurora-A expression.
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10
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Graziadio L, Palumbo V, Cipressa F, Williams BC, Cenci G, Gatti M, Goldberg ML, Bonaccorsi S. Phenotypic characterization of diamond (dind), a Drosophila gene required for multiple aspects of cell division. Chromosoma 2018; 127:489-504. [PMID: 30120539 DOI: 10.1007/s00412-018-0680-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 08/01/2018] [Accepted: 08/03/2018] [Indexed: 01/04/2023]
Abstract
Many genes are required for the assembly of the mitotic apparatus and for proper chromosome behavior during mitosis and meiosis. A fruitful approach to elucidate the mechanisms underlying cell division is the accurate phenotypic characterization of mutations in these genes. Here, we report the identification and characterization of diamond (dind), an essential Drosophila gene required both for mitosis of larval brain cells and for male meiosis. Larvae homozygous for any of the five EMS-induced mutations die in the third-instar stage and exhibit multiple mitotic defects. Mutant brain cells exhibit poorly condensed chromosomes and frequent chromosome breaks and rearrangements; they also show centriole fragmentation, disorganized mitotic spindles, defective chromosome segregation, endoreduplicated metaphases, and hyperploid and polyploid cells. Comparable phenotypes occur in mutant spermatogonia and spermatocytes. The dind gene encodes a non-conserved protein with no known functional motifs. Although the Dind protein exhibits a rather diffuse localization in both interphase and mitotic cells, fractionation experiments indicate that some Dind is tightly associated with the chromatin. Collectively, these results suggest that loss of Dind affects chromatin organization leading to defects in chromosome condensation and integrity, which in turn affect centriole stability and spindle assembly. However, our results do not exclude the possibility that Dind directly affects some behaviors of the spindle and centrosomes.
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Affiliation(s)
- Lucia Graziadio
- Dipartimento di Biologia e Biotecnologie "C. Darwin", Sapienza, Università di Roma, Rome, Italy
| | - Valeria Palumbo
- Dipartimento di Biologia e Biotecnologie "C. Darwin", Sapienza, Università di Roma, Rome, Italy
| | - Francesca Cipressa
- Dipartimento di Biologia e Biotecnologie "C. Darwin", Sapienza, Università di Roma, Rome, Italy.,Museo storico della fisica e centro di studi e ricerche Enrico Fermi, Rome, Italy
| | - Byron C Williams
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, 14853, USA
| | - Giovanni Cenci
- Dipartimento di Biologia e Biotecnologie "C. Darwin", Sapienza, Università di Roma, Rome, Italy.,Istituto Pasteur Fondazione Cenci Bolognetti, Rome, Italy
| | - Maurizio Gatti
- Dipartimento di Biologia e Biotecnologie "C. Darwin", Sapienza, Università di Roma, Rome, Italy.,Istituto di Biologia e Patologia Molecolari (IBPM) del CNR, Rome, Italy
| | - Michael L Goldberg
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, 14853, USA.
| | - Silvia Bonaccorsi
- Dipartimento di Biologia e Biotecnologie "C. Darwin", Sapienza, Università di Roma, Rome, Italy.
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11
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Merigliano C, Marzio A, Renda F, Somma MP, Gatti M, Vernì F. A Role for the Twins Protein Phosphatase (PP2A-B55) in the Maintenance of Drosophila Genome Integrity. Genetics 2017; 205:1151-1167. [PMID: 28040742 PMCID: PMC5340330 DOI: 10.1534/genetics.116.192781] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 12/21/2016] [Indexed: 01/14/2023] Open
Abstract
The protein phosphatase 2A (PP2A) is a conserved heterotrimeric enzyme that regulates several cellular processes including the DNA damage response and mitosis. Consistent with these functions, PP2A is mutated in many types of cancer and acts as a tumor suppressor. In mammalian cells, PP2A inhibition results in DNA double strand breaks (DSBs) and chromosome aberrations (CABs). However, the mechanisms through which PP2A prevents DNA damage are still unclear. Here, we focus on the role of the Drosophila twins (tws) gene in the maintenance of chromosome integrity; tws encodes the B regulatory subunit (B/B55) of PP2A. Mutations in tws cause high frequencies of CABs (0.5 CABs/cell) in Drosophila larval brain cells and lead to an abnormal persistence of γ-H2Av repair foci. However, mutations that disrupt the PP4 phosphatase activity impair foci dissolution but do not cause CABs, suggesting that a delayed foci regression is not clastogenic. We also show that Tws is required for activation of the G2/M DNA damage checkpoint while PP4 is required for checkpoint recovery, a result that points to a conserved function of these phosphatases from flies to humans. Mutations in the ATM-coding gene tefu are strictly epistatic to tws mutations for the CAB phenotype, suggesting that failure to dephosphorylate an ATM substrate(s) impairs DNA DSBs repair. In addition, mutations in the Ku70 gene, which do not cause CABs, completely suppress CAB formation in tws Ku70 double mutants. These results suggest the hypothesis that an improperly phosphorylated Ku70 protein can lead to DNA damage and CABs.
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Affiliation(s)
- Chiara Merigliano
- Dipartimento di Biologia e Biotecnologie "C. Darwin," Sapienza, Università di Roma, 00185, Italy
| | - Antonio Marzio
- Dipartimento di Biologia e Biotecnologie "C. Darwin," Sapienza, Università di Roma, 00185, Italy
| | - Fioranna Renda
- Dipartimento di Biologia e Biotecnologie "C. Darwin," Sapienza, Università di Roma, 00185, Italy
| | - Maria Patrizia Somma
- Istituto di Biologia e Patologia Molecolari del Consiglio Nazionale delle Ricerche, Sapienza, Università di Roma, 00185, Italy
| | - Maurizio Gatti
- Dipartimento di Biologia e Biotecnologie "C. Darwin," Sapienza, Università di Roma, 00185, Italy
- Istituto di Biologia e Patologia Molecolari del Consiglio Nazionale delle Ricerche, Sapienza, Università di Roma, 00185, Italy
| | - Fiammetta Vernì
- Dipartimento di Biologia e Biotecnologie "C. Darwin," Sapienza, Università di Roma, 00185, Italy
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12
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Melters DP, Nye J, Zhao H, Dalal Y. Chromatin Dynamics in Vivo: A Game of Musical Chairs. Genes (Basel) 2015; 6:751-76. [PMID: 26262644 PMCID: PMC4584328 DOI: 10.3390/genes6030751] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 07/17/2015] [Accepted: 07/28/2015] [Indexed: 01/30/2023] Open
Abstract
Histones are a major component of chromatin, the nucleoprotein complex fundamental to regulating transcription, facilitating cell division, and maintaining genome integrity in almost all eukaryotes. In addition to canonical, replication-dependent histones, replication-independent histone variants exist in most eukaryotes. In recent years, steady progress has been made in understanding how histone variants assemble, their involvement in development, mitosis, transcription, and genome repair. In this review, we will focus on the localization of the major histone variants H3.3, CENP-A, H2A.Z, and macroH2A, as well as how these variants have evolved, their structural differences, and their functional significance in vivo.
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Affiliation(s)
- Daniël P Melters
- Chromatin Structure and Epigenetics Mechanisms Unit, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 41 Library Drive, Bethesda, MD 20892, USA.
| | - Jonathan Nye
- Chromatin Structure and Epigenetics Mechanisms Unit, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 41 Library Drive, Bethesda, MD 20892, USA.
| | - Haiqing Zhao
- Chromatin Structure and Epigenetics Mechanisms Unit, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 41 Library Drive, Bethesda, MD 20892, USA.
- Biophysics Graduate Program, University of Maryland, College Park, MD 20742, USA.
| | - Yamini Dalal
- Chromatin Structure and Epigenetics Mechanisms Unit, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 41 Library Drive, Bethesda, MD 20892, USA.
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