1
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Lebdy R, Patouillard J, Larroque M, Urbach S, Abou Merhi R, Larroque C, Ribeyre C. The organizer of chromatin topology RIF1 ensures cellular resilience to DNA replication stress. Life Sci Alliance 2023; 6:e202101186. [PMID: 36746532 PMCID: PMC9906048 DOI: 10.26508/lsa.202101186] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 01/23/2023] [Accepted: 01/23/2023] [Indexed: 02/08/2023] Open
Abstract
Eukaryotic genomes are duplicated from thousands of replication origins that fire sequentially forming a defined spatiotemporal pattern of replication clusters. The temporal order of DNA replication is determined by chromatin architecture and, more specifically, by chromatin contacts that are stabilized by RIF1. Here, we show that RIF1 localizes near newly synthesized DNA. In cells exposed to the DNA replication inhibitor aphidicolin, suppression of RIF1 markedly decreased the efficacy of isolation of proteins on nascent DNA, suggesting that the isolation of proteins on nascent DNA procedure is biased by chromatin topology. RIF1 was required to limit the accumulation of DNA lesions induced by aphidicolin treatment and promoted the recruitment of cohesins in the vicinity of nascent DNA. Collectively, the data suggest that the stabilization of chromatin topology by RIF1 limits replication-associated genomic instability.
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Affiliation(s)
- Rana Lebdy
- Institut de Génétique Humaine, CNRS UMR9002, Université de Montpellier, Montpellier, France
- Doctoral School of Sciences and Technology-DSST, Rafic Hariri Campus, Lebanese University, Hadath, Lebanon
| | - Julie Patouillard
- Institut de Génétique Humaine, CNRS UMR9002, Université de Montpellier, Montpellier, France
| | | | - Serge Urbach
- Institut de Génomique Fonctionnelle, CNRS UMR5203, INSERM U1191, Université de Montpellier, Montpellier, France
| | - Raghida Abou Merhi
- Doctoral School of Sciences and Technology-DSST, Rafic Hariri Campus, Lebanese University, Hadath, Lebanon
| | - Christian Larroque
- Institut de Recherche en Cancérologie de Montpellier, INSERM U1194, Université de Montpellier, Montpellier, France
| | - Cyril Ribeyre
- Institut de Génétique Humaine, CNRS UMR9002, Université de Montpellier, Montpellier, France
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2
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Liu C, Yu P, Ren Z, Yao F, Wang L, Hu G, Li P, Zhao Q. Rif1 Regulates Self-Renewal and Impedes Mesendodermal Differentiation of Mouse Embryonic Stem Cells. Stem Cell Rev Rep 2023:10.1007/s12015-023-10525-1. [PMID: 36971904 PMCID: PMC10366267 DOI: 10.1007/s12015-023-10525-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/02/2023] [Indexed: 03/29/2023]
Abstract
Abstract
Background
RAP1 interacting factor 1 (Rif1) is highly expressed in mice embryos and mouse embryonic stem cells (mESCs). It plays critical roles in telomere length homeostasis, DNA damage, DNA replication timing and ERV silencing. However, whether Rif1 regulates early differentiation of mESC is still unclear.
Methods
In this study, we generated a Rif1 conditional knockout mouse embryonic stem (ES) cell line based on Cre-loxP system. Western blot, flow cytometry, quantitative real-time polymerase chain reaction (qRT-PCR), RNA high-throughput sequencing (RNA-Seq), chromatin immunoprecipitation followed high-throughput sequencing (ChIP-Seq), chromatin immunoprecipitation quantitative PCR (ChIP-qPCR), immunofluorescence, and immunoprecipitation were employed for phenotype and molecular mechanism assessment.
Results
Rif1 plays important roles in self-renewal and pluripotency of mESCs and loss of Rif1 promotes mESC differentiation toward the mesendodermal germ layers. We further show that Rif1 interacts with histone H3K27 methyltransferase EZH2, a subunit of PRC2, and regulates the expression of developmental genes by directly binding to their promoters. Rif1 deficiency reduces the occupancy of EZH2 and H3K27me3 on mesendodermal gene promoters and activates ERK1/2 activities.
Conclusion
Rif1 is a key factor in regulating the pluripotency, self-renewal, and lineage specification of mESCs. Our research provides new insights into the key roles of Rif1 in connecting epigenetic regulations and signaling pathways for cell fate determination and lineage specification of mESCs.
Graphical abstract
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3
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Kong N, Liu Z, Chan YW. RIF1 suppresses the formation of single-stranded ultrafine anaphase bridges via protein phosphatase 1. Cell Rep 2023; 42:112032. [PMID: 36719798 DOI: 10.1016/j.celrep.2023.112032] [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: 05/19/2022] [Revised: 11/07/2022] [Accepted: 01/09/2023] [Indexed: 01/31/2023] Open
Abstract
Resolution of ultrafine anaphase bridges (UFBs) must be completed before cytokinesis to ensure sister-chromatid disjunction. RIF1 is involved in UFB resolution by a mechanism that is not yet clear. Here, we show that RIF1 functions in mitosis to inhibit the formation of 53BP1 nuclear bodies and micronuclei. Meanwhile, RIF1 localizes on PICH-coated double-stranded UFBs but not on RPA-coated single-stranded UFBs. Depletion of RIF1 leads to an elevated level of RPA-coated UFBs, in a BLM-dependent manner. RIF1 interacts with all three isoforms of protein phosphatase 1 (PP1) at its CI domain in anaphase when CDK1 activity declines. CDK1 negatively regulates RIF1-PP1 interaction via the CIII domain of RIF1. Importantly, depletion of PP1 phenocopies RIF1 depletion, and phosphorylation-resistant mutant of PICH shows reduced interaction with the BTR complex and bypasses the need of RIF1 in preventing the formation of single-stranded UFBs. Overall, our data show that PP1 is the effector of RIF1 in UFB resolution.
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Affiliation(s)
- Nannan Kong
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
| | - Zeyuan Liu
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
| | - Ying Wai Chan
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China.
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4
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Histone chaperone ASF1 acts with RIF1 to promote DNA end joining in BRCA1-deficient cells. J Biol Chem 2022; 298:101979. [PMID: 35472331 PMCID: PMC9127577 DOI: 10.1016/j.jbc.2022.101979] [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: 11/11/2021] [Revised: 04/12/2022] [Accepted: 04/13/2022] [Indexed: 12/29/2022] Open
Abstract
Replication timing regulatory factor 1 (RIF1) acts downstream of p53-binding protein 53BP1 to inhibit the resection of DNA broken ends, which plays critical roles in determining the DNA double-strand break repair pathway choice between nonhomologous end joining and homologous recombination (HR). However, the mechanism by which this choice is made is not yet clear. In this study, we identified that histone chaperone protein ASF1 associates with RIF1 and regulates RIF1-dependent functions in the DNA damage response. Similar to loss of RIF1, we found that loss of ASF1 resulted in resistance to poly (ADP-ribose) polymerase (PARP) inhibition in BRCA1-deficient cells with restored HR and decreased telomere fusion in telomeric repeat–binding protein 2 (TRF2)-depleted cells. Moreover, we showed that these functions of ASF1 are dependent on its interaction with RIF1 but not on its histone chaperone activity. Thus, our study supports a new role for ASF1 in dictating double-strand break repair choice. Considering that the status of 53BP1–RIF1 axis is important in determining the outcome of PARP inhibitor–based therapy in BRCA1- or HR-deficient cancers, the identification of ASF1 function in this critical pathway uncovers an interesting connection between these S-phase events, which may reveal new strategies to overcome PARP inhibitor resistance.
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5
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Provasek VE, Mitra J, Malojirao VH, Hegde ML. DNA Double-Strand Breaks as Pathogenic Lesions in Neurological Disorders. Int J Mol Sci 2022; 23:ijms23094653. [PMID: 35563044 PMCID: PMC9099445 DOI: 10.3390/ijms23094653] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 04/19/2022] [Accepted: 04/19/2022] [Indexed: 02/07/2023] Open
Abstract
The damage and repair of DNA is a continuous process required to maintain genomic integrity. DNA double-strand breaks (DSBs) are the most lethal type of DNA damage and require timely repair by dedicated machinery. DSB repair is uniquely important to nondividing, post-mitotic cells of the central nervous system (CNS). These long-lived cells must rely on the intact genome for a lifetime while maintaining high metabolic activity. When these mechanisms fail, the loss of certain neuronal populations upset delicate neural networks required for higher cognition and disrupt vital motor functions. Mammalian cells engage with several different strategies to recognize and repair chromosomal DSBs based on the cellular context and cell cycle phase, including homologous recombination (HR)/homology-directed repair (HDR), microhomology-mediated end-joining (MMEJ), and the classic non-homologous end-joining (NHEJ). In addition to these repair pathways, a growing body of evidence has emphasized the importance of DNA damage response (DDR) signaling, and the involvement of heterogeneous nuclear ribonucleoprotein (hnRNP) family proteins in the repair of neuronal DSBs, many of which are linked to age-associated neurological disorders. In this review, we describe contemporary research characterizing the mechanistic roles of these non-canonical proteins in neuronal DSB repair, as well as their contributions to the etiopathogenesis of selected common neurological diseases.
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Affiliation(s)
- Vincent E. Provasek
- Department of Neurosurgery, Center for Neuroregeneration, Houston Methodist Research Institute, Houston, TX 77030, USA; (V.E.P.); (V.H.M.)
- College of Medicine, Texas A&M University, College Station, TX 77843, USA
| | - Joy Mitra
- Department of Neurosurgery, Center for Neuroregeneration, Houston Methodist Research Institute, Houston, TX 77030, USA; (V.E.P.); (V.H.M.)
- Correspondence: (J.M.); (M.L.H.)
| | - Vikas H. Malojirao
- Department of Neurosurgery, Center for Neuroregeneration, Houston Methodist Research Institute, Houston, TX 77030, USA; (V.E.P.); (V.H.M.)
| | - Muralidhar L. Hegde
- Department of Neurosurgery, Center for Neuroregeneration, Houston Methodist Research Institute, Houston, TX 77030, USA; (V.E.P.); (V.H.M.)
- College of Medicine, Texas A&M University, College Station, TX 77843, USA
- Department of Neurosciences, Weill Cornell Medical College, New York, NY 11021, USA
- Correspondence: (J.M.); (M.L.H.)
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6
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Balasubramanian S, Andreani M, Andrade JG, Saha T, Sundaravinayagam D, Garzón J, Zhang W, Popp O, Hiraga SI, Rahjouei A, Rosen DB, Mertins P, Chait BT, Donaldson AD, Di Virgilio M. Protection of nascent DNA at stalled replication forks is mediated by phosphorylation of RIF1 intrinsically disordered region. eLife 2022; 11:e75047. [PMID: 35416772 PMCID: PMC9007588 DOI: 10.7554/elife.75047] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 03/30/2022] [Indexed: 12/22/2022] Open
Abstract
RIF1 is a multifunctional protein that plays key roles in the regulation of DNA processing. During repair of DNA double-strand breaks (DSBs), RIF1 functions in the 53BP1-Shieldin pathway that inhibits resection of DNA ends to modulate the cellular decision on which repair pathway to engage. Under conditions of replication stress, RIF1 protects nascent DNA at stalled replication forks from degradation by the DNA2 nuclease. How these RIF1 activities are regulated at the post-translational level has not yet been elucidated. Here, we identified a cluster of conserved ATM/ATR consensus SQ motifs within the intrinsically disordered region (IDR) of mouse RIF1 that are phosphorylated in proliferating B lymphocytes. We found that phosphorylation of the conserved IDR SQ cluster is dispensable for the inhibition of DSB resection by RIF1, but is essential to counteract DNA2-dependent degradation of nascent DNA at stalled replication forks. Therefore, our study identifies a key molecular feature that enables the genome-protective function of RIF1 during DNA replication stress.
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Affiliation(s)
- Sandhya Balasubramanian
- Laboratory of Genome Diversification & Integrity, Max Delbrück Center for Molecular Medicine in the Helmholtz AssociationBerlinGermany
- Freie Universität BerlinBerlinGermany
| | - Matteo Andreani
- Laboratory of Genome Diversification & Integrity, Max Delbrück Center for Molecular Medicine in the Helmholtz AssociationBerlinGermany
- Freie Universität BerlinBerlinGermany
| | - Júlia Goncalves Andrade
- Laboratory of Genome Diversification & Integrity, Max Delbrück Center for Molecular Medicine in the Helmholtz AssociationBerlinGermany
| | - Tannishtha Saha
- Laboratory of Genome Diversification & Integrity, Max Delbrück Center for Molecular Medicine in the Helmholtz AssociationBerlinGermany
- Freie Universität BerlinBerlinGermany
| | - Devakumar Sundaravinayagam
- Laboratory of Genome Diversification & Integrity, Max Delbrück Center for Molecular Medicine in the Helmholtz AssociationBerlinGermany
| | - Javier Garzón
- Institute of Medical Sciences, University of Aberdeen, ForesterhillAberdeenUnited Kingdom
| | - Wenzhu Zhang
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller UniversityNew YorkUnited States
| | - Oliver Popp
- Proteomics Platform, Max Delbrück Center for Molecular Medicine in the Helmholtz Association and Berlin Institute of HealthBerlinGermany
| | - Shin-ichiro Hiraga
- Institute of Medical Sciences, University of Aberdeen, ForesterhillAberdeenUnited Kingdom
| | - Ali Rahjouei
- Laboratory of Genome Diversification & Integrity, Max Delbrück Center for Molecular Medicine in the Helmholtz AssociationBerlinGermany
| | - Daniel B Rosen
- Laboratory of Molecular Immunology, The Rockefeller UniversityNew YorkUnited States
| | - Philipp Mertins
- Proteomics Platform, Max Delbrück Center for Molecular Medicine in the Helmholtz Association and Berlin Institute of HealthBerlinGermany
| | - Brian T Chait
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller UniversityNew YorkUnited States
| | - Anne D Donaldson
- Institute of Medical Sciences, University of Aberdeen, ForesterhillAberdeenUnited Kingdom
| | - Michela Di Virgilio
- Laboratory of Genome Diversification & Integrity, Max Delbrück Center for Molecular Medicine in the Helmholtz AssociationBerlinGermany
- Charité-Universitätsmedizin BerlinBerlinGermany
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7
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Feng S, Ma S, Li K, Gao S, Ning S, Shang J, Guo R, Chen Y, Blumenfeld B, Simon I, Li Q, Guo R, Xu D. RIF1-ASF1-mediated high-order chromatin structure safeguards genome integrity. Nat Commun 2022; 13:957. [PMID: 35177609 PMCID: PMC8854732 DOI: 10.1038/s41467-022-28588-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 02/01/2022] [Indexed: 11/12/2022] Open
Abstract
The 53BP1-RIF1 pathway antagonizes resection of DNA broken ends and confers PARP inhibitor sensitivity on BRCA1-mutated tumors. However, it is unclear how this pathway suppresses initiation of resection. Here, we identify ASF1 as a partner of RIF1 via an interacting manner similar to its interactions with histone chaperones CAF-1 and HIRA. ASF1 is recruited to distal chromatin flanking DNA breaks by 53BP1-RIF1 and promotes non-homologous end joining (NHEJ) using its histone chaperone activity. Epistasis analysis shows that ASF1 acts in the same NHEJ pathway as RIF1, but via a parallel pathway with the shieldin complex, which suppresses resection after initiation. Moreover, defects in end resection and homologous recombination (HR) in BRCA1-deficient cells are largely suppressed by ASF1 deficiency. Mechanistically, ASF1 compacts adjacent chromatin by heterochromatinization to protect broken DNA ends from BRCA1-mediated resection. Taken together, our findings identify a RIF1-ASF1 histone chaperone complex that promotes changes in high-order chromatin structure to stimulate the NHEJ pathway for DSB repair. The 53BP1-RIF1 pathway is important for DNA repair. Here, the authors identified the histone chaperone ASF1, which functions as a suppressor of DNA end resection through changing high-order chromatin structure, as a partner of RIF1. This finding links DNA repair and dynamic changes of high-order chromatin structure.
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Affiliation(s)
- Sumin Feng
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, 100871, Beijing, China
| | - Sai Ma
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, 100871, Beijing, China
| | - Kejiao Li
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, 100871, Beijing, China
| | - Shengxian Gao
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, 100871, Beijing, China
| | - Shaokai Ning
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, 100871, Beijing, China
| | - Jinfeng Shang
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, 100871, Beijing, China
| | - Ruiyuan Guo
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, 100871, Beijing, China
| | - Yingying Chen
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, 100871, Beijing, China
| | - Britny Blumenfeld
- Department of Microbiology and Molecular Genetics, Institute of Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University, Jerusalem, 91120, Israel
| | - Itamar Simon
- Department of Microbiology and Molecular Genetics, Institute of Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University, Jerusalem, 91120, Israel
| | - Qing Li
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, 100871, Beijing, China.,Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, 100871, Beijing, China
| | - Rong Guo
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, 100871, Beijing, China
| | - Dongyi Xu
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, 100871, Beijing, China.
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8
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RIF1 acts in DNA repair through phosphopeptide recognition of 53BP1. Mol Cell 2022; 82:1359-1371.e9. [PMID: 35216668 PMCID: PMC8995355 DOI: 10.1016/j.molcel.2022.01.025] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 12/09/2021] [Accepted: 01/27/2022] [Indexed: 12/14/2022]
Abstract
The chromatin-binding protein 53BP1 promotes DNA repair by orchestrating the recruitment of downstream effectors including PTIP, RIF1, and shieldin to DNA double-strand break sites. While we know how PTIP recognizes 53BP1, the molecular details of RIF1 recruitment to DNA-damage sites remains undefined. Here, we report that RIF1 is a phosphopeptide-binding protein that directly interacts with three phosphorylated 53BP1 epitopes. The RIF1-binding sites on 53BP1 share an essential LxL motif followed by two closely apposed phosphorylated residues. Simultaneous mutation of these sites on 53BP1 abrogates RIF1 accumulation into ionizing-radiation-induced foci, but surprisingly, only fully compromises 53BP1-dependent DNA repair when an alternative mode of shieldin recruitment to DNA-damage sites is also disabled. Intriguingly, this alternative mode of recruitment still depends on RIF1 but does not require its interaction with 53BP1. RIF1 therefore employs phosphopeptide recognition to promote DNA repair but also modifies shieldin action independently of 53BP1 binding.
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9
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Malyavko AN, Petrova OA, Zvereva MI, Polshakov VI, Dontsova OA. Telomere length regulation by Rif1 protein from Hansenula polymorpha. eLife 2022; 11:75010. [PMID: 35129114 PMCID: PMC8820739 DOI: 10.7554/elife.75010] [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: 10/26/2021] [Accepted: 01/14/2022] [Indexed: 11/17/2022] Open
Abstract
Rif1 is a large multifaceted protein involved in various processes of DNA metabolism – from telomere length regulation and replication to double-strand break repair. The mechanistic details of its action, however, are often poorly understood. Here, we report functional characterization of the Rif1 homologue from methylotrophic thermotolerant budding yeast Hansenula polymorpha DL-1. We show that, similar to other yeast species, H. polymorpha Rif1 suppresses telomerase-dependent telomere elongation. We uncover two novel modes of Rif1 recruitment at H. polymorpha telomeres: via direct DNA binding and through the association with the Ku heterodimer. Both of these modes (at least partially) require the intrinsically disordered N-terminal extension – a region of the protein present exclusively in yeast species. We also demonstrate that Rif1 binds Stn1 and promotes its accumulation at telomeres in H. polymorpha.
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Affiliation(s)
- Alexander N Malyavko
- Faculty of Chemistry and Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russian Federation
| | - Olga A Petrova
- Faculty of Chemistry and Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russian Federation
| | - Maria I Zvereva
- Faculty of Chemistry and Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russian Federation
| | - Vladimir I Polshakov
- Center for Magnetic Tomography and Spectroscopy, Faculty of Fundamental Medicine, Lomonosov Moscow State University, Moscow, Russian Federation
| | - Olga A Dontsova
- Faculty of Chemistry and Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russian Federation.,Center of Life Sciences, Skolkovo Institute of Science and Technology, Moscow, Russian Federation.,Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow, Russian Federation
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10
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Alavi S, Ghadiri H, Dabirmanesh B, Khajeh K. SPR Analysis of SUMO-Murine Rap1-Interacting Factor 1 C-Terminal Domain Interaction with G4. BIOSENSORS 2022; 12:bios12010037. [PMID: 35049665 PMCID: PMC8774283 DOI: 10.3390/bios12010037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Revised: 01/05/2022] [Accepted: 01/07/2022] [Indexed: 12/26/2022]
Abstract
One of the advantages of surface plasmon resonance is its sensitivity and real-time analyses performed by this method. These characteristics allow us to further investigate the interactions of challenging proteins like Rap1-interacting factor 1 (Rif1). Rif1 is a crucial protein responsible for regulating different cellular processes including DNA replication, repair, and transcription. Mammalian Rif1 is yet to be fully characterized, partly because it is predicted to be intrinsically disordered for a large portion of its polypeptide. This protein has recently been the target of research as a potential biomarker in many cancers. Therefore, finding its most potent interacting partner is of utmost importance. Previous studies showed Rif1’s affinity towards structured DNAs and amongst them, T6G24 was superior. Recent studies have shown mouse Rif1 (muRif1) C-terminal domain’s (CTD) role in binding to G-quadruplexes (G4). There were many concerns in investigating the Rif1 and G4 interaction, which can be minimized using SPR. Therefore, for the first time, we have assessed its binding with G4 at nano-molar concentrations with SPR which seems to be crucial for its binding analyses. Our results indicate that muRif1-CTD has a high affinity for this G4 sequence as it shows a very low KD (6 ± 1 nM).
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Affiliation(s)
- Sana Alavi
- Department of Nanobiotechnology, Faculty of Biological Sciences, Tarbiat Modares University, Tehran 14115-154, Iran;
| | - Hamed Ghadiri
- Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran 14115-154, Iran; (H.G.); (B.D.)
| | - Bahareh Dabirmanesh
- Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran 14115-154, Iran; (H.G.); (B.D.)
| | - Khosro Khajeh
- Department of Nanobiotechnology, Faculty of Biological Sciences, Tarbiat Modares University, Tehran 14115-154, Iran;
- Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran 14115-154, Iran; (H.G.); (B.D.)
- Correspondence: ; Tel./Fax: +98-(21)-8288-4717
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11
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Yoshizawa-Sugata N, Yamazaki S, Mita-Yoshida K, Ono T, Nishito Y, Masai H. Loss of full-length DNA replication regulator Rif1 in two-cell embryos is associated with zygotic transcriptional activation. J Biol Chem 2021; 297:101367. [PMID: 34736895 PMCID: PMC8686075 DOI: 10.1016/j.jbc.2021.101367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 10/17/2021] [Accepted: 10/20/2021] [Indexed: 11/21/2022] Open
Abstract
Rif1 regulates DNA replication timing and double-strand break repair, and its depletion induces transcriptional bursting of two-cell (2C) zygote-specific genes in mouse ES cells. However, how Rif1 regulates zygotic transcription is unclear. We show here that Rif1 depletion promotes the formation of a unique Zscan4 enhancer structure harboring both histone H3 lysine 27 acetylation (H3K27ac) and moderate levels of silencing chromatin mark H3K9me3. Curiously, another enhancer mark H3K4me1 is missing, whereas DNA methylation is still maintained in the structure, which spreads across gene bodies and neighboring regions within the Zscan4 gene cluster. We also found by function analyses of Rif1 domains in ES cells that ectopic expression of Rif1 lacking N-terminal domain results in upregulation of 2C transcripts. This appears to be caused by dominant negative inhibition of endogenous Rif1 protein localization at the nuclear periphery through formation of hetero-oligomers between the N-terminally truncated and endogenous forms. Strikingly, in murine 2C embryos, most of Rif1-derived polypeptides are expressed as truncated forms in soluble nuclear or cytosolic fraction and are likely nonfunctional. Toward the morula stage, the full-length form of Rif1 gradually increased. Our results suggest that the absence of the functional full-length Rif1 due to its instability or alternative splicing and potential inactivation of Rif1 through dominant inhibition by N-terminally truncated Rif1 polypeptides may be involved in 2C-specific transcription program.
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Key Words
- 2c, two-cell (embryo)
- 4-oht, 4-hydroxytamoxifen
- dox, doxycycline
- erv, endogenous retrovirus
- es, embryonic stem
- hpf, hours post fertilization
- idr, intrinsic disordered region
- ivf, in vitro fertilization
- kd, knockdown
- ko, knockout
- rt, room temperature
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Affiliation(s)
| | - Satoshi Yamazaki
- Genome Dynamics Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Kaoru Mita-Yoshida
- Center for Basic Technology Research, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Tomio Ono
- Center for Basic Technology Research, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Yasumasa Nishito
- Center for Basic Technology Research, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Hisao Masai
- Genome Dynamics Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan.
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12
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Blasiak J, Szczepańska J, Sobczuk A, Fila M, Pawlowska E. RIF1 Links Replication Timing with Fork Reactivation and DNA Double-Strand Break Repair. Int J Mol Sci 2021; 22:11440. [PMID: 34768871 PMCID: PMC8583789 DOI: 10.3390/ijms222111440] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 10/20/2021] [Accepted: 10/22/2021] [Indexed: 11/16/2022] Open
Abstract
Replication timing (RT) is a cellular program to coordinate initiation of DNA replication in all origins within the genome. RIF1 (replication timing regulatory factor 1) is a master regulator of RT in human cells. This role of RIF1 is associated with binding G4-quadruplexes and changes in 3D chromatin that may suppress origin activation over a long distance. Many effects of RIF1 in fork reactivation and DNA double-strand (DSB) repair (DSBR) are underlined by its interaction with TP53BP1 (tumor protein p53 binding protein). In G1, RIF1 acts antagonistically to BRCA1 (BRCA1 DNA repair associated), suppressing end resection and homologous recombination repair (HRR) and promoting non-homologous end joining (NHEJ), contributing to DSBR pathway choice. RIF1 is an important element of intra-S-checkpoints to recover damaged replication fork with the involvement of HRR. High-resolution microscopic studies show that RIF1 cooperates with TP53BP1 to preserve 3D structure and epigenetic markers of genomic loci disrupted by DSBs. Apart from TP53BP1, RIF1 interact with many other proteins, including proteins involved in DNA damage response, cell cycle regulation, and chromatin remodeling. As impaired RT, DSBR and fork reactivation are associated with genomic instability, a hallmark of malignant transformation, RIF1 has a diagnostic, prognostic, and therapeutic potential in cancer. Further studies may reveal other aspects of common regulation of RT, DSBR, and fork reactivation by RIF1.
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Affiliation(s)
- Janusz Blasiak
- Department of Molecular Genetics, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz, Poland
| | - Joanna Szczepańska
- Department of Pediatric Dentistry, Medical University of Lodz, 92-216 Lodz, Poland;
| | - Anna Sobczuk
- Department of Gynaecology and Obstetrics, Medical University of Lodz, 93-338 Lodz, Poland;
| | - Michal Fila
- Department of Developmental Neurology and Epileptology, Polish Mother’s Memorial Hospital Research Institute, 93-338 Lodz, Poland;
| | - Elzbieta Pawlowska
- Department of Orthodontics, Medical University of Lodz, 92-217 Lodz, Poland;
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13
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Ciardo D, Haccard O, Narassimprakash H, Cornu D, Guerrera IC, Goldar A, Marheineke K. Polo-like kinase 1 (Plk1) regulates DNA replication origin firing and interacts with Rif1 in Xenopus. Nucleic Acids Res 2021; 49:9851-9869. [PMID: 34469577 PMCID: PMC8464078 DOI: 10.1093/nar/gkab756] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 08/16/2021] [Accepted: 08/20/2021] [Indexed: 12/12/2022] Open
Abstract
The activation of eukaryotic DNA replication origins needs to be strictly controlled at multiple steps in order to faithfully duplicate the genome and to maintain its stability. How the checkpoint recovery and adaptation protein Polo-like kinase 1 (Plk1) regulates the firing of replication origins during non-challenged S phase remained an open question. Using DNA fiber analysis, we show that immunodepletion of Plk1 in the Xenopus in vitro system decreases replication fork density and initiation frequency. Numerical analyses suggest that Plk1 reduces the overall probability and synchrony of origin firing. We used quantitative chromatin proteomics and co-immunoprecipitations to demonstrate that Plk1 interacts with firing factors MTBP/Treslin/TopBP1 as well as with Rif1, a known regulator of replication timing. Phosphopeptide analysis by LC/MS/MS shows that the C-terminal domain of Rif1, which is necessary for its repressive action on origins through protein phosphatase 1 (PP1), can be phosphorylated in vitro by Plk1 on S2058 in its PP1 binding site. The phosphomimetic S2058D mutant interrupts the Rif1-PP1 interaction and modulates DNA replication. Collectively, our study provides molecular insights into how Plk1 regulates the spatio-temporal replication program and suggests that Plk1 controls origin activation at the level of large chromatin domains in vertebrates.
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Affiliation(s)
- Diletta Ciardo
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France
| | - Olivier Haccard
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France
| | - Hemalatha Narassimprakash
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France
| | - David Cornu
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France
| | - Ida Chiara Guerrera
- Proteomics platform Necker, Université de Paris - Structure Fédérative de Recherche Necker, INSERM US24/CNRS UMS3633, Paris 75015, France
| | - Arach Goldar
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France
| | - Kathrin Marheineke
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France
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14
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Jia W, Kim SH, Scalf MA, Tonzi P, Millikin RJ, Guns WM, Liu L, Mastrocola AS, Smith LM, Huang TT, Tibbetts RS. Fused in sarcoma regulates DNA replication timing and kinetics. J Biol Chem 2021; 297:101049. [PMID: 34375640 PMCID: PMC8403768 DOI: 10.1016/j.jbc.2021.101049] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Revised: 07/12/2021] [Accepted: 08/03/2021] [Indexed: 11/17/2022] Open
Abstract
Fused in sarcoma (FUS) encodes an RNA-binding protein with diverse roles in transcriptional activation and RNA splicing. While oncogenic fusions of FUS and transcription factor DNA-binding domains are associated with soft tissue sarcomas, dominant mutations in FUS can cause amyotrophic lateral sclerosis. FUS has also been implicated in genome maintenance. However, the underlying mechanisms of its actions in genome stability are unknown. Here, we applied gene editing, functional reconstitution, and integrated proteomics and transcriptomics to illuminate roles for FUS in DNA replication and repair. Consistent with a supportive role in DNA double-strand break repair, FUS-deficient cells exhibited subtle alterations in the recruitment and retention of double-strand break-associated factors, including 53BP1 and BRCA1. FUS-/- cells also exhibited reduced proliferative potential that correlated with reduced speed of replication fork progression, diminished loading of prereplication complexes, enhanced micronucleus formation, and attenuated expression and splicing of S-phase-associated genes. Finally, FUS-deficient cells exhibited genome-wide alterations in DNA replication timing that were reversed upon re-expression of FUS complementary DNA. We also showed that FUS-dependent replication domains were enriched in transcriptionally active chromatin and that FUS was required for the timely replication of transcriptionally active DNA. These findings suggest that alterations in DNA replication kinetics and programming contribute to genome instability and functional defects in FUS-deficient cells.
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Affiliation(s)
- Weiyan Jia
- Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Sang Hwa Kim
- Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Mark A Scalf
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Peter Tonzi
- Department of Biochemistry and Molecular Pharmacology, New York University Langone Health, New York, New York, USA
| | - Robert J Millikin
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - William M Guns
- Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Lu Liu
- Department of Biostatistics and Medical Informatics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Adam S Mastrocola
- Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Lloyd M Smith
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Tony T Huang
- Department of Biochemistry and Molecular Pharmacology, New York University Langone Health, New York, New York, USA
| | - Randal S Tibbetts
- Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA.
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15
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Ghadiri H, Alavi S, Dabirmanesh B, Khajeh K. Characterization of Interaction of the MBP-Tagged MuRif1-C-Terminal Domain with G-Quadruplex DNA by SPR. BIOCHEMISTRY (MOSCOW) 2021; 86:898-905. [PMID: 34284714 DOI: 10.1134/s0006297921070105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
One of the main players in the cell-specific replication timing pattern is Rap1 interacting factor-1 (Rif1). Rif1 protein consists of N-terminal and C-terminal domains and an intrinsically disordered region in between. It has been suggested that both N- and C-termini of Rif1 are capable of binding to DNA with particularly high affinity to cruciform DNA structures. In the present study, we expressed, solubilized, and purified the maltose-binding protein-tagged murine Rif1 C-terminal domain (MBP-muRif1-CTD). Biological activity of the purified protein was assessed by the electrophoretic mobility shift assay (EMSA) and surface plasmon resonance (SPR). Our results show that the MBP-muRif1-CTD binds G-quadruplex (G4) structure with high affinity (KD 19.0 ± 0.8 nM), as was previously suggested. This study is the first step in investigation of the interaction of MBP-Profinity eXact-muRif1-CTD and G4 by SPR.
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Affiliation(s)
- Hamed Ghadiri
- Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran.
| | - Sana Alavi
- Department of Nanobiotechnology, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran.
| | - Bahareh Dabirmanesh
- Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran.
| | - Khosro Khajeh
- Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran. .,Department of Nanobiotechnology, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
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16
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Alavi S, Ghadiri H, Dabirmanesh B, Moriyama K, Khajeh K, Masai H. G-quadruplex binding protein Rif1, a key regulator of replication timing. J Biochem 2021; 169:1-14. [PMID: 33169133 DOI: 10.1093/jb/mvaa128] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 10/18/2020] [Indexed: 12/19/2022] Open
Abstract
DNA replication is spatially and temporally regulated during S phase to execute efficient and coordinated duplication of entire genome. Various epigenomic mechanisms operate to regulate the timing and locations of replication. Among them, Rif1 plays a major role to shape the 'replication domains' that dictate which segments of the genome are replicated when and where in the nuclei. Rif1 achieves this task by generating higher-order chromatin architecture near nuclear membrane and by recruiting a protein phosphatase. Rif1 is a G4 binding protein, and G4 binding activity of Rif1 is essential for replication timing regulation in fission yeast. In this article, we first summarize strategies by which cells regulate their replication timing and then describe how Rif1 and its interaction with G4 contribute to regulation of chromatin architecture and replication timing.
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Affiliation(s)
| | - Hamed Ghadiri
- Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Bahareh Dabirmanesh
- Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Kenji Moriyama
- Genome Dynamics Project, Department of Basic Medical Sciences, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, Japan
| | - Khosro Khajeh
- Department of Nanobiotechnology.,Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Hisao Masai
- Genome Dynamics Project, Department of Basic Medical Sciences, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, Japan
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17
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Gnan S, Flyamer IM, Klein KN, Castelli E, Rapp A, Maiser A, Chen N, Weber P, Enervald E, Cardoso MC, Bickmore WA, Gilbert DM, Buonomo SCB. Nuclear organisation and replication timing are coupled through RIF1-PP1 interaction. Nat Commun 2021; 12:2910. [PMID: 34006872 PMCID: PMC8131703 DOI: 10.1038/s41467-021-22899-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 03/30/2021] [Indexed: 02/07/2023] Open
Abstract
Three-dimensional genome organisation and replication timing are known to be correlated, however, it remains unknown whether nuclear architecture overall plays an instructive role in the replication-timing programme and, if so, how. Here we demonstrate that RIF1 is a molecular hub that co-regulates both processes. Both nuclear organisation and replication timing depend upon the interaction between RIF1 and PP1. However, whereas nuclear architecture requires the full complement of RIF1 and its interaction with PP1, replication timing is not sensitive to RIF1 dosage. The role of RIF1 in replication timing also extends beyond its interaction with PP1. Availing of this separation-of-function approach, we have therefore identified in RIF1 dual function the molecular bases of the co-dependency of the replication-timing programme and nuclear architecture.
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Affiliation(s)
- Stefano Gnan
- grid.418924.20000 0004 0627 3632Epigenetics & Neurobiology Unit, European Molecular Biology Laboratory (EMBL Rome), Monterotondo, Italy ,grid.4305.20000 0004 1936 7988Institute of Cell Biology, School of Biological Sciences University of Edinburgh, Edinburgh, UK ,grid.462584.90000 0004 0367 1475Present Address: Institut Curie, Université PSL, Sorbonne Université, CNRS UMR3244, Dynamics of Genetic Information, Paris, France
| | - Ilya M. Flyamer
- grid.4305.20000 0004 1936 7988MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, UK
| | - Kyle N. Klein
- grid.255986.50000 0004 0472 0419Department of Biological Science, Florida State University, Tallahassee, FL USA
| | - Eleonora Castelli
- grid.4305.20000 0004 1936 7988Institute of Cell Biology, School of Biological Sciences University of Edinburgh, Edinburgh, UK ,grid.482245.d0000 0001 2110 3787Present Address: Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Alexander Rapp
- grid.6546.10000 0001 0940 1669Cell Biology and Epigenetics, Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
| | - Andreas Maiser
- grid.5252.00000 0004 1936 973XDepartment of Biology II, LMU Munich, Munich, Germany
| | - Naiming Chen
- grid.4305.20000 0004 1936 7988Institute of Cell Biology, School of Biological Sciences University of Edinburgh, Edinburgh, UK
| | - Patrick Weber
- grid.6546.10000 0001 0940 1669Cell Biology and Epigenetics, Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
| | - Elin Enervald
- grid.418924.20000 0004 0627 3632Epigenetics & Neurobiology Unit, European Molecular Biology Laboratory (EMBL Rome), Monterotondo, Italy ,grid.4305.20000 0004 1936 7988Institute of Cell Biology, School of Biological Sciences University of Edinburgh, Edinburgh, UK ,grid.10548.380000 0004 1936 9377Present Address: Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, SE-106 91 Stockholm, Sweden
| | - M. Cristina Cardoso
- grid.6546.10000 0001 0940 1669Cell Biology and Epigenetics, Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
| | - Wendy A. Bickmore
- grid.4305.20000 0004 1936 7988MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, UK
| | - David M. Gilbert
- grid.255986.50000 0004 0472 0419Department of Biological Science, Florida State University, Tallahassee, FL USA
| | - Sara C. B. Buonomo
- grid.418924.20000 0004 0627 3632Epigenetics & Neurobiology Unit, European Molecular Biology Laboratory (EMBL Rome), Monterotondo, Italy ,grid.4305.20000 0004 1936 7988Institute of Cell Biology, School of Biological Sciences University of Edinburgh, Edinburgh, UK
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18
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Shubin CB, Mayangsari R, Swett AD, Greider CW. Rif1 regulates telomere length through conserved HEAT repeats. Nucleic Acids Res 2021; 49:3967-3980. [PMID: 33772576 PMCID: PMC8053089 DOI: 10.1093/nar/gkab206] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 03/10/2021] [Accepted: 03/22/2021] [Indexed: 12/02/2022] Open
Abstract
In budding yeast, Rif1 negatively regulates telomere length, but the mechanism of this regulation has remained elusive. Previous work identified several functional domains of Rif1, but none of these has been shown to mediate telomere length. To define Rif1 domains responsible for telomere regulation, we localized truncations of Rif1 to a single specific telomere and measured telomere length of that telomere compared to bulk telomeres. We found that a domain in the N-terminus containing HEAT repeats, Rif1177–996, was sufficient for length regulation when tethered to the telomere. Charged residues in this region were previously proposed to mediate DNA binding. We found that mutation of these residues disrupted telomere length regulation even when Rif1 was tethered to the telomere. Mutation of other conserved residues in this region, which were not predicted to interact with DNA, also disrupted telomere length maintenance, while mutation of conserved residues distal to this region did not. Our data suggest that conserved amino acids in the region from 436 to 577 play a functional role in telomere length regulation, which is separate from their proposed DNA binding function. We propose that the Rif1 HEAT repeats region represents a protein-protein binding interface that mediates telomere length regulation.
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Affiliation(s)
- Calla B Shubin
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,Biochemistry, Cellular and Molecular Biology Graduate Program, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Rini Mayangsari
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,Department of Molecular Cell and Developmental Biology, University of California, Santa Cruz, CA 95064, USA
| | - Ariel D Swett
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Carol W Greider
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,Department of Molecular Cell and Developmental Biology, University of California, Santa Cruz, CA 95064, USA
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19
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Watts LP, Natsume T, Saito Y, Garzon J, Dong Q, Boteva L, Gilbert N, Kanemaki MT, Hiraga SI, Donaldson AD. The RIF1-long splice variant promotes G1 phase 53BP1 nuclear bodies to protect against replication stress. eLife 2020; 9:e58020. [PMID: 33141022 PMCID: PMC7671687 DOI: 10.7554/elife.58020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 11/02/2020] [Indexed: 12/13/2022] Open
Abstract
Human cells lacking RIF1 are highly sensitive to replication inhibitors, but the reasons for this sensitivity have been enigmatic. Here, we show that RIF1 must be present both during replication stress and in the ensuing recovery period to promote cell survival. Of two isoforms produced by alternative splicing, we find that RIF1-Long alone can protect cells against replication inhibition, but RIF1-Short is incapable of mediating protection. Consistent with this isoform-specific role, RIF1-Long is required to promote the formation of the 53BP1 nuclear bodies that protect unrepaired damage sites in the G1 phase following replication stress. Overall, our observations show that RIF1 is needed at several cell cycle stages after replication insult, with the RIF1-Long isoform playing a specific role during the ensuing G1 phase in damage site protection.
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Affiliation(s)
- Lotte P Watts
- Institute of Medical Sciences, University of AberdeenAberdeenUnited Kingdom
| | - Toyoaki Natsume
- Department of Chromosome Science, National Institute of Genetics, Research Organization of Information and Systems (ROIS)MishimaJapan
- Department of Genetics, The Graduate University for Advanced Studies (SOKENDAI)MishimaJapan
| | - Yuichiro Saito
- Department of Chromosome Science, National Institute of Genetics, Research Organization of Information and Systems (ROIS)MishimaJapan
| | - Javier Garzon
- Institute of Medical Sciences, University of AberdeenAberdeenUnited Kingdom
| | - Qianqian Dong
- Institute of Medical Sciences, University of AberdeenAberdeenUnited Kingdom
| | - Lora Boteva
- MRC Human Genetics Unit, The University of EdinburghEdinburghUnited Kingdom
| | - Nick Gilbert
- MRC Human Genetics Unit, The University of EdinburghEdinburghUnited Kingdom
| | - Masato T Kanemaki
- Department of Chromosome Science, National Institute of Genetics, Research Organization of Information and Systems (ROIS)MishimaJapan
- Department of Genetics, The Graduate University for Advanced Studies (SOKENDAI)MishimaJapan
| | - Shin-ichiro Hiraga
- Institute of Medical Sciences, University of AberdeenAberdeenUnited Kingdom
| | - Anne D Donaldson
- Institute of Medical Sciences, University of AberdeenAberdeenUnited Kingdom
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20
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Shubin CB, Greider CW. The role of Rif1 in telomere length regulation is separable from its role in origin firing. eLife 2020; 9:58066. [PMID: 32597753 PMCID: PMC7371424 DOI: 10.7554/elife.58066] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 06/29/2020] [Indexed: 12/25/2022] Open
Abstract
To examine the established link between DNA replication and telomere length, we tested whether firing of telomeric origins would cause telomere lengthening. We found that RIF1 mutants that block Protein Phosphatase 1 (PP1) binding activated telomeric origins but did not elongate telomeres. In a second approach, we found overexpression of ∆N-Dbf4 and Cdc7 increased DDK activity and activated telomeric origins, yet telomere length was unchanged. We tested a third mechanism to activate origins using the sld3-A mcm5-bob1 mutant that de-regulates the pre-replication complex, and again saw no change in telomere length. Finally, we tested whether mutations in RIF1 that cause telomere elongation would affect origin firing. We found that neither rif1-∆1322 nor rif1HOOK affected firing of telomeric origins. We conclude that telomeric origin firing does not cause telomere elongation, and the role of Rif1 in regulating origin firing is separable from its role in regulating telomere length.
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Affiliation(s)
- Calla B Shubin
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States.,Biochemistry, Cellular and Molecular Biology Graduate Program, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Carol W Greider
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States
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21
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RIF1 promotes replication fork protection and efficient restart to maintain genome stability. Nat Commun 2019; 10:3287. [PMID: 31337767 PMCID: PMC6650494 DOI: 10.1038/s41467-019-11246-1] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 07/01/2019] [Indexed: 12/15/2022] Open
Abstract
Homologous recombination (HR) and Fanconi Anemia (FA) pathway proteins in addition to their DNA repair functions, limit nuclease-mediated processing of stalled replication forks. However, the mechanism by which replication fork degradation results in genome instability is poorly understood. Here, we identify RIF1, a non-homologous end joining (NHEJ) factor, to be enriched at stalled replication forks. Rif1 knockout cells are proficient for recombination, but displayed degradation of reversed forks, which depends on DNA2 nuclease activity. Notably, RIF1-mediated protection of replication forks is independent of its function in NHEJ, but depends on its interaction with Protein Phosphatase 1. RIF1 deficiency delays fork restart and results in exposure of under-replicated DNA, which is the precursor of subsequent genomic instability. Our data implicate RIF1 to be an essential factor for replication fork protection, and uncover the mechanisms by which unprotected DNA replication forks can lead to genome instability in recombination-proficient conditions. Replication fork degradation can result in genome instability. Here authors reveal a role for Rif1 protein in protecting stalled replication forks from undergoing extensive, DNA2-dependent, degradation.
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22
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Rif1 promotes association of G-quadruplex (G4) by its specific G4 binding and oligomerization activities. Sci Rep 2019; 9:8618. [PMID: 31197198 PMCID: PMC6565636 DOI: 10.1038/s41598-019-44736-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 04/30/2019] [Indexed: 12/29/2022] Open
Abstract
Rif1 is a conserved protein regulating replication timing and binds preferentially to the vicinity of late-firing/dormant origins in fission yeast. The Rif1 binding sites on the fission yeast genome have an intrinsic potential to generate G-quadruplex (G4) structures to which purified Rif1 preferentially binds. We previously proposed that Rif1 generates chromatin architecture that may determine replication timing by facilitating the chromatin loop formation. Here, we conducted detailed biochemical analyses on Rif1 and its G4 binding. Rif1 prefers sequences containing long stretches of guanines and binds preferentially to the multimeric G4 of parallel or hybrid/mix topology. Rif1 forms oligomers and binds simultaneously to multiple G4. We present a model on how Rif1 may facilitate the formation of chromatin architecture through its G4 binding and oligomerization properties.
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23
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Kobayashi S, Fukatsu R, Kanoh Y, Kakusho N, Matsumoto S, Chaen S, Masai H. Both a Unique Motif at the C Terminus and an N-Terminal HEAT Repeat Contribute to G-Quadruplex Binding and Origin Regulation by the Rif1 Protein. Mol Cell Biol 2019; 39:e00364-18. [PMID: 30510058 PMCID: PMC6362314 DOI: 10.1128/mcb.00364-18] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 09/19/2018] [Accepted: 11/09/2018] [Indexed: 01/11/2023] Open
Abstract
Rif1 is a key factor for spatiotemporal regulation of DNA replication. Rif1 suppresses origin firing in the mid-late replication domains by generating replication-suppressive chromatin architecture and by recruiting a protein phosphatase. In fission yeast, the function of Hsk1, a kinase important for origin firing, can be bypassed by rif1Δ due to the loss of origin suppression. Rif1 specifically binds to G-quadruplex (G4) in vitro Here, we show both conserved N-terminal HEAT repeats and C-terminal nonconserved segments are required for origin suppression. The N-terminal 444 amino acids and the C-terminal 229 amino acids can each mediate specific G4 binding, although high-affinity G4 binding requires the presence of both N- and C-terminal segments. The C-terminal 91 amino acids, although not able to bind to G4, can form a multimer. Furthermore, genetic screening led to identification of two classes of rif1 point mutations that can bypass Hsk1, one that fails to bind to chromatin and one that binds to chromatin. These results illustrate functional domains of Rif1 and indicate importance of both the N-terminal HEAT repeat segment and C-terminal G4 binding/oligomerization domain as well as other functionally unassigned segments of Rif1 in regulation of origin firing.
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Affiliation(s)
- Shunsuke Kobayashi
- Department of Genome Medicine, Tokyo Metropolitan Institute of Medical Science, Kamikitazawa, Setagaya-ku, Tokyo, Japan
- Department of Biosciences, College of Humanities and Sciences, Nihon University, Tokyo, Japan
| | - Rino Fukatsu
- Department of Genome Medicine, Tokyo Metropolitan Institute of Medical Science, Kamikitazawa, Setagaya-ku, Tokyo, Japan
| | - Yutaka Kanoh
- Department of Genome Medicine, Tokyo Metropolitan Institute of Medical Science, Kamikitazawa, Setagaya-ku, Tokyo, Japan
| | - Naoko Kakusho
- Department of Genome Medicine, Tokyo Metropolitan Institute of Medical Science, Kamikitazawa, Setagaya-ku, Tokyo, Japan
| | - Seiji Matsumoto
- Department of Genome Medicine, Tokyo Metropolitan Institute of Medical Science, Kamikitazawa, Setagaya-ku, Tokyo, Japan
| | - Shigeru Chaen
- Department of Correlative Study of Physics and Chemistry, Graduate School of Integrated Basic Sciences, Nihon University, Tokyo, Japan
| | - Hisao Masai
- Department of Genome Medicine, Tokyo Metropolitan Institute of Medical Science, Kamikitazawa, Setagaya-ku, Tokyo, Japan
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24
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The Unresolved Problem of DNA Bridging. Genes (Basel) 2018; 9:genes9120623. [PMID: 30545131 PMCID: PMC6316547 DOI: 10.3390/genes9120623] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 12/08/2018] [Accepted: 12/10/2018] [Indexed: 12/31/2022] Open
Abstract
Accurate duplication and transmission of identical genetic information into offspring cells lies at the heart of a cell division cycle. During the last stage of cellular division, namely mitosis, the fully replicated DNA molecules are condensed into X-shaped chromosomes, followed by a chromosome separation process called sister chromatid disjunction. This process allows for the equal partition of genetic material into two newly born daughter cells. However, emerging evidence has shown that faithful chromosome segregation is challenged by the presence of persistent DNA intertwining structures generated during DNA replication and repair, which manifest as so-called ultra-fine DNA bridges (UFBs) during anaphase. Undoubtedly, failure to disentangle DNA linkages poses a severe threat to mitosis and genome integrity. This review will summarize the possible causes of DNA bridges, particularly sister DNA inter-linkage structures, in an attempt to explain how they may be processed and how they influence faithful chromosome segregation and the maintenance of genome stability.
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25
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An OB-fold complex controls the repair pathways for DNA double-strand breaks. Nat Commun 2018; 9:3925. [PMID: 30254264 PMCID: PMC6156606 DOI: 10.1038/s41467-018-06407-7] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 09/03/2018] [Indexed: 12/29/2022] Open
Abstract
53BP1 with its downstream proteins, RIF1, PTIP and REV7, antagonizes BRCA1-dependent homologous recombination (HR) and promotes non-homologous end joining (NHEJ) in an unclear manner. Here we show that REV7 forms a complex with two proteins, FAM35A and C20ORF196. We demonstrate that FAM35A preferentially binds single-strand DNA (ssDNA) in vitro, and is recruited to DSBs as a complex with C20ORF196 and REV7 downstream of RIF1 in vivo. Epistasis analysis shows that both proteins act in the same pathway as RIF1 in NHEJ. The defects in HR pathway to repair DSBs and the reduction in resection of broken DNA ends in BRCA1-mutant cells can be largely suppressed by inactivating FAM35A or C20ORF196, indicating that FAM35A and C20ORF196 prevent end resection in these cells. Together, our data identified a REV7-FAM35A-C20ORF196 complex that binds and protects broken DNA ends to promote the NHEJ pathway for DSB repair.
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26
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Chan YW, West SC. A new class of ultrafine anaphase bridges generated by homologous recombination. Cell Cycle 2018; 17:2101-2109. [PMID: 30253678 PMCID: PMC6226235 DOI: 10.1080/15384101.2018.1515555] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 08/20/2018] [Indexed: 12/31/2022] Open
Abstract
Ultrafine anaphase bridges (UFBs) are a potential source of genome instability that is a hallmark of cancer. UFBs can arise from DNA catenanes at centromeres/rDNA loci, late replication intermediates induced by replication stress, and DNA linkages at telomeres. Recently, it was reported that DNA intertwinements generated by homologous recombination give rise to a new class of UFBs, which have been termed homologous recombination ultrafine bridges (HR-UFBs). HR-UFBs are decorated with PICH and BLM in anaphase, and are subsequently converted to RPA-coated, single-stranded DNA bridges. Breakage of these sister chromatid entanglements leads to DNA damage that can be repaired by non-homologous end joining in the next cell cycle, but the potential consequences include DNA rearrangements, chromosome translocations and fusions. Visualisation of these HR-UFBs, and knowledge of how they arise, provides a molecular basis to explain how upregulation of homologous recombination or failure to resolve recombination intermediates leads to the development of chromosomal instability observed in certain cancers.
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Affiliation(s)
- Ying Wai Chan
- Department of DNA Recombination and Repair, The Francis Crick Institute, London, UK
| | - Stephen C. West
- Department of DNA Recombination and Repair, The Francis Crick Institute, London, UK
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27
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Mei Y, Liu YB, Cao S, Tian ZW, Zhou HH. RIF1 promotes tumor growth and cancer stem cell-like traits in NSCLC by protein phosphatase 1-mediated activation of Wnt/β-catenin signaling. Cell Death Dis 2018; 9:942. [PMID: 30237512 PMCID: PMC6148239 DOI: 10.1038/s41419-018-0972-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 08/13/2018] [Accepted: 08/20/2018] [Indexed: 12/11/2022]
Abstract
Wnt/β-catenin signaling is essential for proliferation and maintenance of cancer stem cell-like traits of various cancer cells. In non-small-cell lung carcinoma (NSCLC), the mechanisms underlying the hyperactivation of Wnt signaling remain unclear, as mutations in APC and β-catenin genes are rare in NSCLC. RIF1 has been shown upregulated in breast and cervical cancer, this study intends to find out the potential effects of the expression and biological functions of RIF1 in NSCLC. Here we revealed that RIF1 was highly expressed in NCSLC at both mRNA and protein levels. RIF1 expression was significantly associated with clinical stage (P < 0.05) and prognosis (P < 0.001) of NSCLC patients. RIF1 knockdown inhibited NSCLC cell growth in vitro and in vivo, whereas overexpression of RIF1 in NSCLC cell lines promoted cell growth, cell cycle progression and cancer stem cell (CSC)-like properties via promoting PP1-AXIN interaction and thereby activating Wnt/β-catenin signaling. Inhibition of PP1 in RIF1-overexpressed cells counteracted the effects of RIF1 on cell growth and CSC-like phenotype, as well as the Wnt/β-catenin signaling. RIF1 expression was positively correlated with β-catenin at the protein level in 32 NSCLC tissues. RIF1 expression closely related to MYC (r = 0.28, P < 0.001) and CCND1 (r = 0.14, P < 0.01) expression at the mRNA level in cohorts of The Cancer Genome Atlas (TCGA). These results indicated that RIF1 had an oncogenic role as a novel positive regulator of Wnt/β-catenin signaling by directing PP1 to dephosphorylate AXIN; this novel mechanism may present a new therapeutic target for NSCLC.
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Affiliation(s)
- Ying Mei
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, 410008, Changsha P. R., China.,Institute of Clinical Pharmacology, Central South University, Hunan Key Laboratory of Pharmacogenetics, 410078, Changsha P. R., China
| | - Yong-Bin Liu
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, 410008, Changsha P. R., China.,Institute of Clinical Pharmacology, Central South University, Hunan Key Laboratory of Pharmacogenetics, 410078, Changsha P. R., China
| | - Shan Cao
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, 410008, Changsha P. R., China.,Institute of Clinical Pharmacology, Central South University, Hunan Key Laboratory of Pharmacogenetics, 410078, Changsha P. R., China
| | - Zheng-Wen Tian
- Department of Epidemiology and Medical Statistics, Xiangya School of Public Health, Central South University, 410008, Changsha P. R., China
| | - Hong-Hao Zhou
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, 410008, Changsha P. R., China. .,Institute of Clinical Pharmacology, Central South University, Hunan Key Laboratory of Pharmacogenetics, 410078, Changsha P. R., China.
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28
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Hiraga SI, Monerawela C, Katou Y, Shaw S, Clark KR, Shirahige K, Donaldson AD. Budding yeast Rif1 binds to replication origins and protects DNA at blocked replication forks. EMBO Rep 2018; 19:e46222. [PMID: 30104203 PMCID: PMC6123642 DOI: 10.15252/embr.201846222] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 07/17/2018] [Accepted: 07/23/2018] [Indexed: 11/28/2022] Open
Abstract
Despite its evolutionarily conserved function in controlling DNA replication, the chromosomal binding sites of the budding yeast Rif1 protein are not well understood. Here, we analyse genome-wide binding of budding yeast Rif1 by chromatin immunoprecipitation, during G1 phase and in S phase with replication progressing normally or blocked by hydroxyurea. Rif1 associates strongly with telomeres through interaction with Rap1. By comparing genomic binding of wild-type Rif1 and truncated Rif1 lacking the Rap1-interaction domain, we identify hundreds of Rap1-dependent and Rap1-independent chromosome interaction sites. Rif1 binds to centromeres, highly transcribed genes and replication origins in a Rap1-independent manner, associating with both early and late-initiating origins. Interestingly, Rif1 also binds around activated origins when replication progression is blocked by hydroxyurea, suggesting association with blocked forks. Using nascent DNA labelling and DNA combing techniques, we find that in cells treated with hydroxyurea, yeast Rif1 stabilises recently synthesised DNA Our results indicate that, in addition to controlling DNA replication initiation, budding yeast Rif1 plays an ongoing role after initiation and controls events at blocked replication forks.
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Affiliation(s)
| | | | - Yuki Katou
- Institute for Quantitative Biosciences, University of Tokyo, Tokyo, Japan
| | - Sophie Shaw
- Centre for Genome-Enabled Biology and Medicine, University of Aberdeen, Aberdeen, UK
| | - Kate Rm Clark
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
| | | | - Anne D Donaldson
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
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29
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Fontana GA, Reinert JK, Thomä NH, Rass U. Shepherding DNA ends: Rif1 protects telomeres and chromosome breaks. MICROBIAL CELL 2018; 5:327-343. [PMID: 29992129 PMCID: PMC6035837 DOI: 10.15698/mic2018.07.639] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Cells have evolved conserved mechanisms to protect DNA ends, such as those at the termini of linear chromosomes, or those at DNA double-strand breaks (DSBs). In eukaryotes, DNA ends at chromosomal termini are packaged into proteinaceous structures called telomeres. Telomeres protect chromosome ends from erosion, inadvertent activation of the cellular DNA damage response (DDR), and telomere fusion. In contrast, cells must respond to damage-induced DNA ends at DSBs by harnessing the DDR to restore chromosome integrity, avoiding genome instability and disease. Intriguingly, Rif1 (Rap1-interacting factor 1) has been implicated in telomere homeostasis as well as DSB repair. The protein was first identified in Saccharomyces cerevisiae as being part of the proteinaceous telosome. In mammals, RIF1 is not associated with intact telomeres, but was found at chromosome breaks, where RIF1 has emerged as a key mediator of pathway choice between the two evolutionary conserved DSB repair pathways of non-homologous end-joining (NHEJ) and homologous recombination (HR). While this functional dichotomy has long been a puzzle, recent findings link yeast Rif1 not only to telomeres, but also to DSB repair, and mechanistic parallels likely exist. In this review, we will provide an overview of the actions of Rif1 at DNA ends and explore how exclusion of end-processing factors might be the underlying principle allowing Rif1 to fulfill diverse biological roles at telomeres and chromosome breaks.
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Affiliation(s)
- Gabriele A Fontana
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland
| | - Julia K Reinert
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland.,University of Basel, Petersplatz 10, CH-4003 Basel, Switzerland
| | - Nicolas H Thomä
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland
| | - Ulrich Rass
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland
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30
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Bakr A, Köcher S, Volquardsen J, Petersen C, Borgmann K, Dikomey E, Rothkamm K, Mansour WY. Impaired 53BP1/RIF1 DSB mediated end-protection stimulates CtIP-dependent end resection and switches the repair to PARP1-dependent end joining in G1. Oncotarget 2018; 7:57679-57693. [PMID: 27494840 PMCID: PMC5295381 DOI: 10.18632/oncotarget.11023] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Accepted: 07/23/2016] [Indexed: 01/30/2023] Open
Abstract
End processing at DNA double strand breaks (DSB) is a decisive step in repair pathway selection. Here, we investigated the role of 53BP1/RIF1 in limiting BRCA1/CtIP-mediated end resection to control DSB repair pathway choice. ATM orchestrates this process through 53BP1 phosphorylation to promote RIF1 recruitment. As cells enter S/G2-phase, end resection is activated, which displaces pATM from DSB sites and diminishes 53BP1 phosphorylation and RIF1 recruitment. Consistently, the kinetics of ATM and 53BP1 phosphorylation in S/G2-phase concur. We show that defective 53BP1/RIF1-mediated DSB end-protection in G1-phase stimulates CtIP/MRE11-dependent end-resection, which requires Polo-like kinase 3. This end resection activity in G1 was shown to produce only short tracks of ssDNA overhangs, as evidenced by the findings that in 53BP1 depleted cells, (i) RPA focus intensity was significantly lower in G1 compared to that in S/G2 phase, and (ii) EXO1 knockdown did not alter either number or intensity of RPA foci in G1 but significantly decreased the RPA focus intensity in S/G2 phase. Importantly, we report that the observed DSB end resection in G1 phase inhibits DNA-PK-dependent nonhomologous end joining but is not sufficient to stimulate HR. Instead, it switches the repair to the alternative PARP1-dependent end joining pathway.
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Affiliation(s)
- Ali Bakr
- Laboratory of Radiobiology & Experimental Radiooncology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Sabrina Köcher
- Laboratory of Radiobiology & Experimental Radiooncology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Jennifer Volquardsen
- Laboratory of Radiobiology & Experimental Radiooncology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Cordula Petersen
- Department of Radiotherapy and Radiooncology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Kerstin Borgmann
- Laboratory of Radiobiology & Experimental Radiooncology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Ekkehard Dikomey
- Laboratory of Radiobiology & Experimental Radiooncology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Kai Rothkamm
- Laboratory of Radiobiology & Experimental Radiooncology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Wael Y Mansour
- Laboratory of Radiobiology & Experimental Radiooncology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,Tumor Biology Department, National Cancer Institute, Cairo University, Egypt
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31
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Moriyama K, Yoshizawa-Sugata N, Masai H. Oligomer formation and G-quadruplex binding by purified murine Rif1 protein, a key organizer of higher-order chromatin architecture. J Biol Chem 2018; 293:3607-3624. [PMID: 29348174 DOI: 10.1074/jbc.ra117.000446] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2017] [Revised: 12/21/2017] [Indexed: 11/06/2022] Open
Abstract
Rap1-interacting protein 1 (Rif1) regulates telomere length in budding yeast. We previously reported that, in metazoans and fission yeast, Rif1 also plays pivotal roles in controlling genome-wide DNA replication timing. We proposed that Rif1 may assemble chromatin compartments that contain specific replication-timing domains by promoting chromatin loop formation. Rif1 also is involved in DNA lesion repair, restart after replication fork collapse, anti-apoptosis activities, replicative senescence, and transcriptional regulation. Although multiple physiological functions of Rif1 have been characterized, biochemical and structural information on mammalian Rif1 is limited, mainly because of difficulties in purifying the full-length protein. Here, we expressed and purified the 2418-amino-acid-long, full-length murine Rif1 as well as its partially truncated variants in human 293T cells. Hydrodynamic analyses indicated that Rif1 forms elongated or extended homo-oligomers in solution, consistent with the presence of a HEAT-type helical repeat segment known to adopt an elongated shape. We also observed that the purified murine Rif1 bound G-quadruplex (G4) DNA with high specificity and affinity, as was previously shown for Rif1 from fission yeast. Both the N-terminal (HEAT-repeat) and C-terminal segments were involved in oligomer formation and specifically bound G4 DNA, and the central intrinsically disordered polypeptide segment increased the affinity for G4. Of note, pulldown assays revealed that Rif1 simultaneously binds multiple G4 molecules. Our findings support a model in which Rif1 modulates chromatin loop structures through binding to multiple G4 assemblies and by holding chromatin fibers together.
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Affiliation(s)
- Kenji Moriyama
- From the Genome Dynamics Project, Department of Genome Medicine, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan
| | - Naoko Yoshizawa-Sugata
- From the Genome Dynamics Project, Department of Genome Medicine, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan
| | - Hisao Masai
- From the Genome Dynamics Project, Department of Genome Medicine, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan
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32
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Li P, Wang L, Bennett BD, Wang J, Li J, Qin Y, Takaku M, Wade PA, Wong J, Hu G. Rif1 promotes a repressive chromatin state to safeguard against endogenous retrovirus activation. Nucleic Acids Res 2018; 45:12723-12738. [PMID: 29040764 PMCID: PMC5727408 DOI: 10.1093/nar/gkx884] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2017] [Accepted: 10/05/2017] [Indexed: 12/29/2022] Open
Abstract
Transposable elements, including endogenous retroviruses (ERVs), constitute a large fraction of the mammalian genome. They are transcriptionally silenced during early development to protect genome integrity and aberrant transcription. However, the mechanisms that control their repression are not fully understood. To systematically study ERV repression, we carried out an RNAi screen in mouse embryonic stem cells (ESCs) and identified a list of novel regulators. Among them, Rif1 displays the strongest effect. Rif1 depletion by RNAi or gene deletion led to increased transcription and increased chromatin accessibility at ERV regions and their neighboring genes. This transcriptional de-repression becomes more severe when DNA methylation is lost. On the mechanistic level, Rif1 directly occupies ERVs and is required for repressive histone mark H3K9me3 and H3K27me3 assembly and DNA methylation. It interacts with histone methyltransferases and facilitates their recruitment to ERV regions. Importantly, Rif1 represses ERVs in human ESCs as well, and the evolutionally-conserved HEAT-like domain is essential for its function. Finally, Rif1 acts as a barrier during somatic cell reprogramming, and its depletion significantly enhances reprogramming efficiency. Together, our study uncovered many previously uncharacterized repressors of ERVs, and defined an essential role of Rif1 in the epigenetic defense against ERV activation.
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Affiliation(s)
- Pishun Li
- Epigenetics and Stem Cell Biology Laboratory, National Institute of Environmental Health Sciences, RTP, NC 27709, USA
| | - Li Wang
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, China
| | - Brian D. Bennett
- Integrative Bioinformatics Support Group, National Institute of Environmental Health Sciences, RTP, NC 27709, USA
| | - Jiajia Wang
- Epigenetics and Stem Cell Biology Laboratory, National Institute of Environmental Health Sciences, RTP, NC 27709, USA
| | - Jialun Li
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Yufeng Qin
- Epigenetics and Stem Cell Biology Laboratory, National Institute of Environmental Health Sciences, RTP, NC 27709, USA
| | - Motoki Takaku
- Epigenetics and Stem Cell Biology Laboratory, National Institute of Environmental Health Sciences, RTP, NC 27709, USA
| | - Paul A. Wade
- Epigenetics and Stem Cell Biology Laboratory, National Institute of Environmental Health Sciences, RTP, NC 27709, USA
| | - Jiemin Wong
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Guang Hu
- Epigenetics and Stem Cell Biology Laboratory, National Institute of Environmental Health Sciences, RTP, NC 27709, USA
- To whom correspondence should be addressed. Tel: +1 919 541 4755; Fax: +1 919 541 0146;
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33
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Dynamics of RIF1 SUMOylation is regulated by PIAS4 in the maintenance of Genomic Stability. Sci Rep 2017; 7:17367. [PMID: 29234018 PMCID: PMC5727183 DOI: 10.1038/s41598-017-16934-w] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 11/20/2017] [Indexed: 01/29/2023] Open
Abstract
RIF1 plays a key role in inhibiting DNA end resection and promoting NHEJ mediated DNA double stand break repair in G1. However, whether SUMOlyation may regulate RIF1 functions is still largely unknown. Here, we report that RIF1 is SUMOlyated in response to DNA damage. We identified PIAS4 as the primary SUMO E3 ligase required for the SUMOylation of RIF1 protein. Mammalian cells compromised of PIAS4 expression, show impaired RIF1 SUMOylation and defective for the disassembly of DNA damage responsive RIF1 foci. Mechanistically, we show that PIAS4 knockdown abrogates UHRF1-dependent ubiquitination of RIF1, compromising RIF1 protein turnover. We detected intense RPA foci that colocalize with RIF1 foci in PIAS4 knockdown cells. These data highlight an important role of PIAS4-dependent regulation of RIF1, likely mediated by SUMOylation, in the disassembly of RIF1 DNA damage response (DDR) foci. We propose that unresolved RIF1 protein at sites of DNA damage in PIAS4-depleted cells largely accumulates in S phase, and subsequently leads to DNA double strand breaks. Therefore, PIAS4 promotes genomic stability by regulating the timely removal of RIF1 from sites of DNA damage.
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34
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ATM and CDK2 control chromatin remodeler CSB to inhibit RIF1 in DSB repair pathway choice. Nat Commun 2017; 8:1921. [PMID: 29203878 PMCID: PMC5715124 DOI: 10.1038/s41467-017-02114-x] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Accepted: 11/08/2017] [Indexed: 12/13/2022] Open
Abstract
CSB, a member of the SWI2/SNF2 superfamily, is implicated in DNA double-strand break (DSB) repair. However, how it regulates this repair process is poorly understood. Here we uncover that CSB interacts via its newly identified winged helix domain with RIF1, an effector of 53BP1, and that this interaction mediates CSB recruitment to DSBs in S phase. At DSBs, CSB remodels chromatin by evicting histones, which limits RIF1 and its effector MAD2L2 but promotes BRCA1 accumulation. The chromatin remodeling activity of CSB requires not only damage-induced phosphorylation on S10 by ATM but also cell cycle-dependent phosphorylation on S158 by cyclin A-CDK2. Both modifications modulate the interaction of the CSB N-terminal region with its ATPase domain, the activity of which has been previously reported to be autorepressed by the N-terminal region. These results suggest that ATM and CDK2 control the chromatin remodeling activity of CSB in the regulation of DSB repair pathway choice. Cockayne syndrome group B protein (CSB) is a multifunctional chromatin remodeler involved in double-strand break repair. Here the authors investigate the molecular post-translational signals regulating CSB activity.
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35
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Sarlós K, Biebricher A, Petermann EJG, Wuite GJL, Hickson ID. Knotty Problems during Mitosis: Mechanistic Insight into the Processing of Ultrafine DNA Bridges in Anaphase. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2017; 82:187-195. [PMID: 29167280 DOI: 10.1101/sqb.2017.82.033647] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
To survive and proliferate, cells have to faithfully segregate their newly replicated genomic DNA to the two daughter cells. However, the sister chromatids of mitotic chromosomes are frequently interlinked by so-called ultrafine DNA bridges (UFBs) that are visible in the anaphase of mitosis. UFBs can only be detected by the proteins bound to them and not by staining with conventional DNA dyes. These DNA bridges are presumed to represent entangled sister chromatids and hence pose a threat to faithful segregation. A failure to accurately unlink UFB DNA results in chromosome segregation errors and binucleation. This, in turn, compromises genome integrity, which is a hallmark of cancer. UFBs are actively removed during anaphase, and most known UFB-associated proteins are enzymes involved in DNA repair in interphase. However, little is known about the mitotic activities of these enzymes or the exact DNA structures present on UFBs. We focus on the biology of UFBs, with special emphasis on their underlying DNA structure and the decatenation machineries that process UFBs.
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Affiliation(s)
- Kata Sarlós
- Center for Chromosome Stability and Center for Healthy Aging, Department of Cellular and Molecular Medicine, University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Andreas Biebricher
- Department of Physics and Astronomy and LaserLab, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands
| | - Erwin J G Petermann
- Department of Physics and Astronomy and LaserLab, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands
| | - Gijs J L Wuite
- Department of Physics and Astronomy and LaserLab, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands
| | - Ian D Hickson
- Center for Chromosome Stability and Center for Healthy Aging, Department of Cellular and Molecular Medicine, University of Copenhagen, 2200 Copenhagen N, Denmark
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36
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Xu Y, Ning S, Wei Z, Xu R, Xu X, Xing M, Guo R, Xu D. 53BP1 and BRCA1 control pathway choice for stalled replication restart. eLife 2017; 6:30523. [PMID: 29106372 PMCID: PMC5683755 DOI: 10.7554/elife.30523] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 11/04/2017] [Indexed: 12/29/2022] Open
Abstract
The cellular pathways that restart stalled replication forks are essential for genome stability and tumor prevention. However, how many of these pathways exist in cells and how these pathways are selectively activated remain unclear. Here, we describe two major fork restart pathways, and demonstrate that their selection is governed by 53BP1 and BRCA1, which are known to control the pathway choice to repair double-strand DNA breaks (DSBs). Specifically, 53BP1 promotes a fork cleavage-free pathway, whereas BRCA1 facilitates a break-induced replication (BIR) pathway coupled with SLX-MUS complex-mediated fork cleavage. The defect in the first pathway, but not DSB repair, in a 53BP1 mutant is largely corrected by disrupting BRCA1, and vice versa. Moreover, PLK1 temporally regulates the switch of these two pathways through enhancing the assembly of the SLX-MUS complex. Our results reveal two distinct fork restart pathways, which are antagonistically controlled by 53BP1 and BRCA1 in a DSB repair-independent manner.
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Affiliation(s)
- Yixi Xu
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China
| | - Shaokai Ning
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China
| | - Zheng Wei
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China
| | - Ran Xu
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China
| | - Xinlin Xu
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China
| | - Mengtan Xing
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China.,Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
| | - Rong Guo
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China
| | - Dongyi Xu
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China
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37
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Mei Y, Peng C, Liu YB, Wang J, Zhou HH. Silencing RIF1 decreases cell growth, migration and increases cisplatin sensitivity of human cervical cancer cells. Oncotarget 2017; 8:107044-107051. [PMID: 29291010 PMCID: PMC5739795 DOI: 10.18632/oncotarget.22315] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Accepted: 07/26/2017] [Indexed: 12/29/2022] Open
Abstract
Replication timing regulatory factor 1 (RIF1) plays an important role in DNA replication regulation, stem cell pluripotency and DNA repair pathway. However, little is known about the molecular mechanisms and physiological significance of RIF1 in cancer and chemotherapy efficacy. In this study, we found that RIF1 is upregulated in cervical cancer tissues compared with normal tissues both at mRNA and protein levels through online databases. RIF1 knockdown reduced cervical cancer cell growth, colony formation, migration and epithelial-mesenchymal transition (EMT) markers. Flow cytometry analysis indicated that RIF1 knockdown induced apoptosis and G2 cell cycle arrest. Furthermore, RIF1 knockdown increased cisplatin sensitivity, cisplatin-induced G2/M phase arrest, apoptosis and led to defects in DNA repair in a concentration-dependent manner. In terms of mechanism research, increased CDKN1A expression and Bax/Bcl-2/caspase-3 signaling pathway might be involved in the G2/M phase arrest and increased apoptosis in RIF1-silenced cervical cancer cells. Thus, these findings indicate that RIF1 knockdown prior to chemotherapy may be a potential effective therapeutic strategy for cervical cancer.
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Affiliation(s)
- Ying Mei
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha 410008, P. R. China.,Institute of Clinical Pharmacology, Central South University, Hunan Key Laboratory of Pharmacogenetics, Changsha 410078, P. R. China.,Hunan Province Cooperation Innovation Center for Molecular Target New Drug Study, Hengyang 421001, P. R. China
| | - Chen Peng
- Department of music therapy, Sam Houston State University, Huntsville TX 77340, USA
| | - Yong-Bin Liu
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha 410008, P. R. China.,Institute of Clinical Pharmacology, Central South University, Hunan Key Laboratory of Pharmacogenetics, Changsha 410078, P. R. China.,Hunan Province Cooperation Innovation Center for Molecular Target New Drug Study, Hengyang 421001, P. R. China
| | - Jing Wang
- Xiangya school of medicine, Central South University, Changsha 410008, P. R. China
| | - Hong-Hao Zhou
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha 410008, P. R. China.,Institute of Clinical Pharmacology, Central South University, Hunan Key Laboratory of Pharmacogenetics, Changsha 410078, P. R. China.,Hunan Province Cooperation Innovation Center for Molecular Target New Drug Study, Hengyang 421001, P. R. China
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38
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Li L, Poon HY, Hildebrandt MR, Monckton EA, Germain DR, Fahlman RP, Godbout R. Role for RIF1-interacting partner DDX1 in BLM recruitment to DNA double-strand breaks. DNA Repair (Amst) 2017; 55:47-63. [DOI: 10.1016/j.dnarep.2017.05.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 05/01/2017] [Accepted: 05/02/2017] [Indexed: 01/13/2023]
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39
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Mouse Rif1 is a regulatory subunit of protein phosphatase 1 (PP1). Sci Rep 2017; 7:2119. [PMID: 28522851 PMCID: PMC5437018 DOI: 10.1038/s41598-017-01910-1] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 02/13/2017] [Indexed: 12/29/2022] Open
Abstract
Rif1 is a conserved protein that plays essential roles in orchestrating DNA replication timing, controlling nuclear architecture, telomere length and DNA repair. However, the relationship between these different roles, as well as the molecular basis of Rif1 function is still unclear. The association of Rif1 with insoluble nuclear lamina has thus far hampered exhaustive characterization of the associated protein complexes. We devised a protocol that overcomes this problem, and were thus able to discover a number of novel Rif1 interactors, involved in chromatin metabolism and phosphorylation. Among them, we focus here on PP1. Data from different systems have suggested that Rif1-PP1 interaction is conserved and has important biological roles. Using mutagenesis, NMR, isothermal calorimetry and surface plasmon resonance we demonstrate that Rif1 is a high-affinity PP1 adaptor, able to out-compete the well-established PP1-inhibitor I2 in vitro. Our conclusions have important implications for understanding Rif1 diverse roles and the relationship between the biological processes controlled by Rif1.
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40
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Rif1-Dependent Regulation of Genome Replication in Mammals. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1042:259-272. [DOI: 10.1007/978-981-10-6955-0_12] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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41
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Moriyama K, Lai MS, Masai H. Interaction of Rif1 Protein with G-Quadruplex in Control of Chromosome Transactions. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1042:287-310. [PMID: 29357064 DOI: 10.1007/978-981-10-6955-0_14] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Recent studies on G-quadruplex (G4) revealed crucial and conserved functions of G4 in various biological systems. We recently showed that Rif1, a conserved nuclear factor, binds to G4 present in the intergenic regions and plays a major role in spatiotemporal regulation of DNA replication. Rif1 may tether chromatin fibers through binding to G4, generating specific chromatin domains that dictate the replication timing. G4 and its various binding partners are now implicated in many other chromosome regulations, including transcription, replication initiation, recombination, gene rearrangement, and transposition.
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Affiliation(s)
- Kenji Moriyama
- Department of Genome Medicine, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 156-8506, Japan
| | - Mong Sing Lai
- Department of Genome Medicine, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 156-8506, Japan
| | - Hisao Masai
- Department of Genome Medicine, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 156-8506, Japan.
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42
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Ranatunga NS, Forsburg SL. Characterization of a Novel MMS-Sensitive Allele of Schizosaccharomyces pombe mcm4. G3 (BETHESDA, MD.) 2016; 6:3049-3063. [PMID: 27473316 PMCID: PMC5068930 DOI: 10.1534/g3.116.033571] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 07/20/2016] [Indexed: 12/17/2022]
Abstract
The minichromosome maintenance (MCM) complex is the conserved helicase motor of the eukaryotic replication fork. Mutations in the Mcm4 subunit are associated with replication stress and double strand breaks in multiple systems. In this work, we characterize a new temperature-sensitive allele of Schizosaccharomyces pombe mcm4+ Uniquely among known mcm4 alleles, this mutation causes sensitivity to the alkylation damaging agent methyl methanesulfonate (MMS). Even in the absence of treatment or temperature shift, mcm4-c106 cells show increased repair foci of RPA and Rad52, and require the damage checkpoint for viability, indicating genome stress. The mcm4-c106 mutant is synthetically lethal with mutations disrupting fork protection complex (FPC) proteins Swi1 and Swi3. Surprisingly, we found that the deletion of rif1+ suppressed the MMS-sensitive phenotype without affecting temperature sensitivity. Together, these data suggest that mcm4-c106 destabilizes replisome structure.
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Affiliation(s)
- Nimna S Ranatunga
- Program in Molecular and Computational Biology, University of Southern California, Los Angeles, California 90089
| | - Susan L Forsburg
- Program in Molecular and Computational Biology, University of Southern California, Los Angeles, California 90089
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43
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Zaaijer S, Shaikh N, Nageshan RK, Cooper JP. Rif1 Regulates the Fate of DNA Entanglements during Mitosis. Cell Rep 2016; 16:148-160. [PMID: 27320927 PMCID: PMC4929174 DOI: 10.1016/j.celrep.2016.05.077] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 05/06/2016] [Accepted: 05/18/2016] [Indexed: 12/31/2022] Open
Abstract
Clearance of entangled DNA from the anaphase mid-region must accurately proceed in order for chromosomes to segregate with high fidelity. Loss of Taz1 (fission yeast ortholog of human TRF1/TRF2) leads to stalled telomeric replication forks that trigger telomeric entanglements; the resolution of these entanglements fails at ≤20°C. Here, we investigate these entanglements and their promotion by the conserved replication/repair protein Rif1. Rif1 plays no role in taz1Δ fork stalling. Rather, Rif1 localizes to the anaphase mid-region and regulates the resolution of persisting DNA structures. This anaphase role for Rif1 is genetically separate from the role of Rif1 in S/G2, though both roles require binding to PP1 phosphatase, implying spatially and temporally distinct Rif1-regulated phosphatase substrates. Rif1 thus acts as a double-edged sword. Although it inhibits the resolution of taz1Δ telomere entanglements, it promotes the resolution of non-telomeric ultrafine anaphase bridges at ≤20°C. We suggest a unifying model for Rif1's seemingly diverse roles in chromosome segregation in eukaryotes.
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Affiliation(s)
- Sophie Zaaijer
- Laboratory of Biochemistry and Molecular Biology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Nadeem Shaikh
- Laboratory of Biochemistry and Molecular Biology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Rishi Kumar Nageshan
- Laboratory of Biochemistry and Molecular Biology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Julia Promisel Cooper
- Laboratory of Biochemistry and Molecular Biology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA.
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44
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Huang J, Gali H, Paramasivam M, Muniandy P, Gichimu J, Bellani MA, Seidman MM. Single Molecule Analysis of Laser Localized Interstrand Crosslinks. Front Genet 2016; 7:84. [PMID: 27242893 PMCID: PMC4860505 DOI: 10.3389/fgene.2016.00084] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Accepted: 04/22/2016] [Indexed: 12/21/2022] Open
Abstract
DNA interstrand crosslinks (ICLs) block unwinding of the double helix, and have always been regarded as major challenges to replication and transcription. Compounds that form these lesions are very toxic and are frequently used in cancer chemotherapy. We have developed two strategies, both based on immunofluorescence (IF), for studying cellular responses to ICLs. The basis of each is psoralen, a photoactive (by long wave ultraviolet light, UVA) DNA crosslinking agent, to which we have linked an antigen tag. In the one approach, we have taken advantage of DNA fiber and immuno-quantum dot technologies for visualizing the encounter of replication forks with ICLs induced by exposure to UVA lamps. In the other, psoralen ICLs are introduced into nuclei in live cells in regions of interest defined by a UVA laser. The antigen tag can be displayed by conventional IF, as can the recruitment and accumulation of DNA damage response proteins to the laser localized ICLs. However, substantial difference between the technologies creates considerable uncertainty as to whether conclusions from one approach are applicable to those of the other. In this report, we have employed the fiber/quantum dot methodology to determine lesion density and spacing on individual DNA molecules carrying laser localized ICLs. We have performed the same measurements on DNA fibers with ICLs induced by exposure of psoralen to UVA lamps. Remarkably, we find little difference in the adduct distribution on fibers prepared from cells exposed to the different treatment protocols. Furthermore, there is considerable similarity in patterns of replication in the vicinity of the ICLs introduced by the two techniques.
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Affiliation(s)
- Jing Huang
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health Baltimore, MD, USA
| | - Himabindu Gali
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health Baltimore, MD, USA
| | - Manikandan Paramasivam
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health Baltimore, MD, USA
| | - Parameswary Muniandy
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health Baltimore, MD, USA
| | - Julia Gichimu
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health Baltimore, MD, USA
| | - Marina A Bellani
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health Baltimore, MD, USA
| | - Michael M Seidman
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health Baltimore, MD, USA
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45
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Mattarocci S, Hafner L, Lezaja A, Shyian M, Shore D. Rif1: A Conserved Regulator of DNA Replication and Repair Hijacked by Telomeres in Yeasts. Front Genet 2016; 7:45. [PMID: 27066066 PMCID: PMC4811881 DOI: 10.3389/fgene.2016.00045] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Accepted: 03/14/2016] [Indexed: 12/12/2022] Open
Abstract
Rap1-interacting factor 1 (Rif1) was originally identified in the budding yeast Saccharomyces cerevisiae as a telomere-binding protein that negatively regulates telomerase-mediated telomere elongation. Although this function is conserved in the distantly related fission yeast Schizosaccharomyces pombe, recent studies, both in yeasts and in metazoans, reveal that Rif1 also functions more globally, both in the temporal control of DNA replication and in DNA repair. Rif1 proteins are large and characterized by N-terminal HEAT repeats, predicted to form an elongated alpha-helical structure. In addition, all Rif1 homologs contain two short motifs, abbreviated RVxF/SILK, that are implicated in recruitment of the PP1 (yeast Glc7) phosphatase. In yeasts the RVxF/SILK domains have been shown to play a role in control of DNA replication initiation, at least in part through targeted de-phosphorylation of proteins in the pre-Replication Complex. In human cells Rif1 is recruited to DNA double-strand breaks through an interaction with 53BP1 where it counteracts DNA resection, thus promoting repair by non-homologous end-joining. This function requires the N-terminal HEAT repeat-containing domain. Interestingly, this domain is also implicated in DNA end protection at un-capped telomeres in yeast. We conclude by discussing the deployment of Rif1 at telomeres in yeasts from both an evolutionary perspective and in light of its recently discovered global functions.
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Affiliation(s)
- Stefano Mattarocci
- Department of Molecular Biology and Institute for Genetics and Genomics in Geneva, University of Geneva Geneva, Switzerland
| | - Lukas Hafner
- Department of Molecular Biology and Institute for Genetics and Genomics in Geneva, University of Geneva Geneva, Switzerland
| | - Aleksandra Lezaja
- Department of Molecular Biology and Institute for Genetics and Genomics in Geneva, University of Geneva Geneva, Switzerland
| | - Maksym Shyian
- Department of Molecular Biology and Institute for Genetics and Genomics in Geneva, University of Geneva Geneva, Switzerland
| | - David Shore
- Department of Molecular Biology and Institute for Genetics and Genomics in Geneva, University of Geneva Geneva, Switzerland
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46
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Foti R, Gnan S, Cornacchia D, Dileep V, Bulut-Karslioglu A, Diehl S, Buness A, Klein FA, Huber W, Johnstone E, Loos R, Bertone P, Gilbert DM, Manke T, Jenuwein T, Buonomo SCB. Nuclear Architecture Organized by Rif1 Underpins the Replication-Timing Program. Mol Cell 2016; 61:260-73. [PMID: 26725008 PMCID: PMC4724237 DOI: 10.1016/j.molcel.2015.12.001] [Citation(s) in RCA: 125] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Revised: 07/22/2015] [Accepted: 11/13/2015] [Indexed: 02/08/2023]
Abstract
DNA replication is temporally and spatially organized in all eukaryotes, yet the molecular control and biological function of the replication-timing program are unclear. Rif1 is required for normal genome-wide regulation of replication timing, but its molecular function is poorly understood. Here we show that in mouse embryonic stem cells, Rif1 coats late-replicating domains and, with Lamin B1, identifies most of the late-replicating genome. Rif1 is an essential determinant of replication timing of non-Lamin B1-bound late domains. We further demonstrate that Rif1 defines and restricts the interactions between replication-timing domains during the G1 phase, thereby revealing a function of Rif1 as organizer of nuclear architecture. Rif1 loss affects both number and replication-timing specificity of the interactions between replication-timing domains. In addition, during the S phase, Rif1 ensures that replication of interacting domains is temporally coordinated. In summary, our study identifies Rif1 as the molecular link between nuclear architecture and replication-timing establishment in mammals.
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Affiliation(s)
- Rossana Foti
- Mouse Biology Unit, EMBL Monterotondo, Via Ramarini 32, 00015 Monterotondo, Italy
| | - Stefano Gnan
- Mouse Biology Unit, EMBL Monterotondo, Via Ramarini 32, 00015 Monterotondo, Italy
| | - Daniela Cornacchia
- Mouse Biology Unit, EMBL Monterotondo, Via Ramarini 32, 00015 Monterotondo, Italy
| | - Vishnu Dileep
- Department of Biological Science, Florida State University, Tallahassee, FL 32306, USA
| | - Aydan Bulut-Karslioglu
- Max Planck Institute of Immunbiology and Epigenetics, Stubeweg 51, 79108 Freiburg, Germany
| | - Sarah Diehl
- Max Planck Institute of Immunbiology and Epigenetics, Stubeweg 51, 79108 Freiburg, Germany
| | - Andreas Buness
- Mouse Biology Unit, EMBL Monterotondo, Via Ramarini 32, 00015 Monterotondo, Italy
| | - Felix A Klein
- Genome Biology Unit, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Wolfgang Huber
- Genome Biology Unit, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Ewan Johnstone
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Trust Genome Campus, Cambridge CB10 1SD, UK
| | - Remco Loos
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Trust Genome Campus, Cambridge CB10 1SD, UK
| | - Paul Bertone
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Trust Genome Campus, Cambridge CB10 1SD, UK; Genome Biology and Developmental Biology Units, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany; Wellcome Trust-Medical Research Council Stem Cell Institute, University of Cambridge, Tennis Court Road, Cambridge CB2 1QR, UK
| | - David M Gilbert
- Department of Biological Science, Florida State University, Tallahassee, FL 32306, USA
| | - Thomas Manke
- Max Planck Institute of Immunbiology and Epigenetics, Stubeweg 51, 79108 Freiburg, Germany
| | - Thomas Jenuwein
- Max Planck Institute of Immunbiology and Epigenetics, Stubeweg 51, 79108 Freiburg, Germany
| | - Sara C B Buonomo
- Mouse Biology Unit, EMBL Monterotondo, Via Ramarini 32, 00015 Monterotondo, Italy.
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47
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Rif1 binds to G quadruplexes and suppresses replication over long distances. Nat Struct Mol Biol 2015; 22:889-97. [PMID: 26436827 DOI: 10.1038/nsmb.3102] [Citation(s) in RCA: 116] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 09/03/2015] [Indexed: 12/20/2022]
Abstract
Rif1 regulates replication timing and repair of double-strand DNA breaks. Using a chromatin immunoprecipitation-sequencing method, we identified 35 high-affinity Rif1-binding sites in fission yeast chromosomes. Binding sites tended to be located near dormant origins and to contain at least two copies of a conserved motif, CNWWGTGGGGG. Base substitution within these motifs resulted in complete loss of Rif1 binding and in activation of late-firing or dormant origins located up to 50 kb away. We show that Rif1-binding sites adopt G quadruplex-like structures in vitro, in a manner dependent on the conserved sequence and on other G tracts, and that purified Rif1 preferentially binds to this structure. These results suggest that Rif1 recognizes and binds G quadruplex-like structures at selected intergenic regions, thus generating local chromatin structures that may exert long-range suppressive effects on origin firing.
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48
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Hengeveld RCC, de Boer HR, Schoonen PM, de Vries EGE, Lens SMA, van Vugt MATM. Rif1 Is Required for Resolution of Ultrafine DNA Bridges in Anaphase to Ensure Genomic Stability. Dev Cell 2015; 34:466-74. [PMID: 26256213 DOI: 10.1016/j.devcel.2015.06.014] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 05/21/2015] [Accepted: 06/16/2015] [Indexed: 12/27/2022]
Abstract
Sister-chromatid disjunction in anaphase requires the resolution of DNA catenanes by topoisomerase II together with Plk1-interacting checkpoint helicase (PICH) and Bloom's helicase (BLM). We here identify Rif1 as a factor involved in the resolution of DNA catenanes that are visible as ultrafine DNA bridges (UFBs) in anaphase to which PICH and BLM localize. Rif1, which during interphase functions downstream of 53BP1 in DNA repair, is recruited to UFBs in a PICH-dependent fashion, but independently of 53BP1 or BLM. Similar to PICH and BLM, Rif1 promotes the resolution of UFBs: its depletion increases the frequency of nucleoplasmic bridges and RPA70-positive UFBs in late anaphase. Moreover, in the absence of Rif1, PICH, or BLM, more nuclear bodies with damaged DNA arise in ensuing G1 cells, when chromosome decatenation is impaired. Our data reveal a thus far unrecognized function for Rif1 in the resolution of UFBs during anaphase to protect genomic integrity.
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Affiliation(s)
- Rutger C C Hengeveld
- Department of Molecular Cancer Research, University Medical Center Utrecht, Universiteitsweg 100, 3584 CG Utrecht, the Netherlands
| | - H Rudolf de Boer
- Department of Medical Oncology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9723 GZ Groningen, the Netherlands
| | - Pepijn M Schoonen
- Department of Medical Oncology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9723 GZ Groningen, the Netherlands
| | - Elisabeth G E de Vries
- Department of Medical Oncology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9723 GZ Groningen, the Netherlands
| | - Susanne M A Lens
- Department of Molecular Cancer Research, University Medical Center Utrecht, Universiteitsweg 100, 3584 CG Utrecht, the Netherlands.
| | - Marcel A T M van Vugt
- Department of Medical Oncology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9723 GZ Groningen, the Netherlands
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49
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Sreesankar E, Bharathi V, Mishra RK, Mishra K. Drosophila Rif1 is an essential gene and controls late developmental events by direct interaction with PP1-87B. Sci Rep 2015; 5:10679. [PMID: 26022086 PMCID: PMC4448129 DOI: 10.1038/srep10679] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Accepted: 04/16/2015] [Indexed: 11/24/2022] Open
Abstract
Rif1, identified as a regulator of telomerase in yeast, is an evolutionarily conserved protein and functions in diverse processes including telomere length regulation, epigenetic gene regulation, anti-checkpoint activity, DNA repair and establishing timing of firing at replication origins. Previously we had identified that all Rif1 homologues have PP1 interacting SILK-RVxF motif. In the present study, we show that Drosophila Rif1 is essential for normal fly development and loss of dRif1 impairs temporal regulation of initiation of DNA replication. In multiple tissues dRif1 colocalizes with HP1, a protein known to orchestrate timing of replication in fly. dRif1 associates with chromosomes in a mitotic stage-dependent manner coinciding with dephosphorylation of histones. Ectopic expression of dRif1 causes enlarged larval imaginal discs and early pupal lethality which is completely reversed by co-expression of PP1 87B, the major protein phosphatase in Drosophila, indicating genetic and functional interaction. These findings suggest that dRif1 is an adaptor for PP1 and functions by recruiting PP1 to multiple sites on the chromosome.
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Affiliation(s)
- Easwaran Sreesankar
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad- 500 046, INDIA
| | | | - Rakesh K Mishra
- Centre for Cellular and Molecular Biology, Uppal road, Hyderabad-500 007, INDIA
| | - Krishnaveni Mishra
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad- 500 046, INDIA
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50
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Abstract
DNA double-strand breaks (DSBs) in cells can undergo nucleolytic degradation to generate long 3' single-stranded DNA tails. This process is termed DNA end resection, and its occurrence effectively commits to break repair via homologous recombination, which entails the acquisition of genetic information from an intact, homologous donor DNA sequence. Recent advances, prompted by the identification of the nucleases that catalyze resection, have revealed intricate layers of functional redundancy, interconnectedness, and regulation. Here, we review the current state of the field with an emphasis on the major questions that remain to be answered. Topics addressed will include how resection initiates via the introduction of an endonucleolytic incision close to the break end, the molecular mechanism of the conserved MRE11 complex in conjunction with Sae2/CtIP within such a model, the role of BRCA1 and 53BP1 in regulating resection initiation in mammalian cells, the influence of chromatin in the resection process, and potential roles of novel factors.
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Affiliation(s)
- James M Daley
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06520, USA.
| | - Hengyao Niu
- Molecular and Cellular Biochemistry Department, Indiana University, Bloomington, IN 47405, USA
| | - Adam S Miller
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Patrick Sung
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06520, USA
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