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  1. Article ; Online: The MCM Helicase Motor of the Eukaryotic Replisome.

    Abid Ali, Ferdos / Costa, Alessandro

    Journal of molecular biology

    2016  Volume 428, Issue 9 Pt B, Page(s) 1822–1832

    Abstract: The MCM motor of the CMG helicase powers ahead of the eukaryotic replication machinery to unwind DNA, in a process that requires ATP hydrolysis. The reconstitution of DNA replication in vitro has established the succession of events that lead to ... ...

    Abstract The MCM motor of the CMG helicase powers ahead of the eukaryotic replication machinery to unwind DNA, in a process that requires ATP hydrolysis. The reconstitution of DNA replication in vitro has established the succession of events that lead to replication origin activation by the MCM and recent studies have started to elucidate the structural basis of duplex DNA unwinding. Despite the exciting progress, how the MCM translocates on DNA remains a matter of debate.
    MeSH term(s) Adenosine Triphosphate/metabolism ; DNA Helicases/chemistry ; DNA Helicases/metabolism ; DNA Replication ; Eukaryota/enzymology ; Eukaryota/metabolism ; Hydrolysis ; Minichromosome Maintenance Proteins/metabolism ; Models, Biological ; Models, Molecular ; Protein Conformation
    Chemical Substances Adenosine Triphosphate (8L70Q75FXE) ; DNA Helicases (EC 3.6.4.-) ; Minichromosome Maintenance Proteins (EC 3.6.4.12)
    Language English
    Publishing date 2016-01-30
    Publishing country Netherlands
    Document type Journal Article ; Review ; Research Support, Non-U.S. Gov't
    ZDB-ID 80229-3
    ISSN 1089-8638 ; 0022-2836
    ISSN (online) 1089-8638
    ISSN 0022-2836
    DOI 10.1016/j.jmb.2016.01.024
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article: The MCM Helicase Motor of the Eukaryotic Replisome

    Abid Ali, Ferdos / Costa, Alessandro

    Journal of Molecular Biology. 2016 May 08, v. 428

    2016  

    Abstract: The MCM motor of the CMG helicase powers ahead of the eukaryotic replication machinery to unwind DNA, in a process that requires ATP hydrolysis. The reconstitution of DNA replication in vitro has established the succession of events that lead to ... ...

    Abstract The MCM motor of the CMG helicase powers ahead of the eukaryotic replication machinery to unwind DNA, in a process that requires ATP hydrolysis. The reconstitution of DNA replication in vitro has established the succession of events that lead to replication origin activation by the MCM and recent studies have started to elucidate the structural basis of duplex DNA unwinding. Despite the exciting progress, how the MCM translocates on DNA remains a matter of debate.
    Keywords DNA ; DNA replication ; adenosine triphosphate ; hydrolysis ; replication origin
    Language English
    Dates of publication 2016-0508
    Size p. 1822-1832.
    Publishing place Elsevier Ltd
    Document type Article
    ZDB-ID 80229-3
    ISSN 1089-8638 ; 0022-2836
    ISSN (online) 1089-8638
    ISSN 0022-2836
    DOI 10.1016/j.jmb.2016.01.024
    Database NAL-Catalogue (AGRICOLA)

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  3. Article ; Online: The mechanism of eukaryotic CMG helicase activation.

    Douglas, Max E / Ali, Ferdos Abid / Costa, Alessandro / Diffley, John F X

    Nature

    2018  Volume 555, Issue 7695, Page(s) 265–268

    Abstract: The initiation of eukaryotic DNA replication occurs in two discrete stages: first, the minichromosome maintenance (MCM) complex assembles as a head-to-head double hexamer that encircles duplex replication origin DNA during G1 phase; then, 'firing factors' ...

    Abstract The initiation of eukaryotic DNA replication occurs in two discrete stages: first, the minichromosome maintenance (MCM) complex assembles as a head-to-head double hexamer that encircles duplex replication origin DNA during G1 phase; then, 'firing factors' convert each double hexamer into two active Cdc45-MCM-GINS helicases (CMG) during S phase. This second stage requires separation of the two origin DNA strands and remodelling of the double hexamer so that each MCM hexamer encircles a single DNA strand. Here we show that the MCM complex, which hydrolyses ATP during double-hexamer formation, remains stably bound to ADP in the double hexamer. Firing factors trigger ADP release, and subsequent ATP binding promotes stable CMG assembly. CMG assembly is accompanied by initial DNA untwisting and separation of the double hexamer into two discrete but inactive CMG helicases. Mcm10, together with ATP hydrolysis, then triggers further DNA untwisting and helicase activation. After activation, the two CMG helicases translocate in an 'N terminus-first' direction, and in doing so pass each other within the origin; this requires that each helicase is bound entirely to single-stranded DNA. Our experiments elucidate the mechanism of eukaryotic replicative helicase activation, which we propose provides a fail-safe mechanism for bidirectional replisome establishment.
    MeSH term(s) Adenosine Diphosphate/chemistry ; Adenosine Diphosphate/metabolism ; Adenosine Triphosphate/chemistry ; Adenosine Triphosphate/metabolism ; Cell Cycle Proteins/metabolism ; DNA Helicases/chemistry ; DNA Helicases/metabolism ; DNA Replication ; DNA, Single-Stranded/biosynthesis ; DNA, Single-Stranded/chemistry ; DNA, Single-Stranded/metabolism ; DNA-Binding Proteins/metabolism ; Enzyme Activation ; Enzyme Stability ; Minichromosome Maintenance Proteins/metabolism ; Nucleic Acid Conformation ; Replication Origin ; Saccharomyces cerevisiae/enzymology ; Saccharomyces cerevisiae Proteins/chemistry ; Saccharomyces cerevisiae Proteins/metabolism
    Chemical Substances Cell Cycle Proteins ; DNA, Single-Stranded ; DNA-Binding Proteins ; Saccharomyces cerevisiae Proteins ; Adenosine Diphosphate (61D2G4IYVH) ; Adenosine Triphosphate (8L70Q75FXE) ; DNA Helicases (EC 3.6.4.-) ; Minichromosome Maintenance Proteins (EC 3.6.4.12)
    Language English
    Publishing date 2018-02-28
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 120714-3
    ISSN 1476-4687 ; 0028-0836
    ISSN (online) 1476-4687
    ISSN 0028-0836
    DOI 10.1038/nature25787
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Molecular Basis for ATP-Hydrolysis-Driven DNA Translocation by the CMG Helicase of the Eukaryotic Replisome.

    Eickhoff, Patrik / Kose, Hazal B / Martino, Fabrizio / Petojevic, Tatjana / Abid Ali, Ferdos / Locke, Julia / Tamberg, Nele / Nans, Andrea / Berger, James M / Botchan, Michael R / Yardimci, Hasan / Costa, Alessandro

    Cell reports

    2021  Volume 28, Issue 10, Page(s) 2673–2688.e8

    Abstract: In the eukaryotic replisome, DNA unwinding by the Cdc45-MCM-Go-Ichi-Ni-San (GINS) (CMG) helicase requires a hexameric ring-shaped ATPase named minichromosome maintenance (MCM), which spools single-stranded DNA through its central channel. Not all six ... ...

    Abstract In the eukaryotic replisome, DNA unwinding by the Cdc45-MCM-Go-Ichi-Ni-San (GINS) (CMG) helicase requires a hexameric ring-shaped ATPase named minichromosome maintenance (MCM), which spools single-stranded DNA through its central channel. Not all six ATPase sites are required for unwinding; however, the helicase mechanism is unknown. We imaged ATP-hydrolysis-driven translocation of the CMG using cryo-electron microscopy (cryo-EM) and found that the six MCM subunits engage DNA using four neighboring protomers at a time, with ATP binding promoting DNA engagement. Morphing between different helicase states leads us to suggest a non-symmetric hand-over-hand rotary mechanism, explaining the asymmetric requirements of ATPase function around the MCM ring of the CMG. By imaging of a higher-order replisome assembly, we find that the Mrc1-Csm3-Tof1 fork-stabilization complex strengthens the interaction between parental duplex DNA and the CMG at the fork, which might support the coupling between DNA translocation and fork unwinding.
    MeSH term(s) Adenosine Triphosphatases/metabolism ; Adenosine Triphosphate/metabolism ; Amino Acid Sequence ; Animals ; Cryoelectron Microscopy ; DNA/metabolism ; DNA/ultrastructure ; DNA Helicases/chemistry ; DNA Helicases/metabolism ; DNA Helicases/ultrastructure ; DNA-Directed DNA Polymerase/metabolism ; Drosophila Proteins/metabolism ; Drosophila melanogaster/enzymology ; Eukaryota/enzymology ; Hydrolysis ; Models, Molecular ; Multienzyme Complexes/metabolism ; Protein Domains ; Saccharomyces cerevisiae/metabolism
    Chemical Substances Drosophila Proteins ; Multienzyme Complexes ; Adenosine Triphosphate (8L70Q75FXE) ; DNA (9007-49-2) ; DNA synthesome (EC 2.7.7.-) ; DNA-Directed DNA Polymerase (EC 2.7.7.7) ; Adenosine Triphosphatases (EC 3.6.1.-) ; DNA Helicases (EC 3.6.4.-)
    Language English
    Publishing date 2021-01-08
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 2649101-1
    ISSN 2211-1247 ; 2211-1247
    ISSN (online) 2211-1247
    ISSN 2211-1247
    DOI 10.1016/j.celrep.2019.07.104
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Shulin packages axonemal outer dynein arms for ciliary targeting.

    Mali, Girish R / Ali, Ferdos Abid / Lau, Clinton K / Begum, Farida / Boulanger, Jérôme / Howe, Jonathan D / Chen, Zhuo A / Rappsilber, Juri / Skehel, Mark / Carter, Andrew P

    Science (New York, N.Y.)

    2020  Volume 371, Issue 6532, Page(s) 910–916

    Abstract: The main force generators in eukaryotic cilia and flagella are axonemal outer dynein arms (ODAs). During ciliogenesis, these ~1.8-megadalton complexes are assembled in the cytoplasm and targeted to cilia by an unknown mechanism. Here, we used the ... ...

    Abstract The main force generators in eukaryotic cilia and flagella are axonemal outer dynein arms (ODAs). During ciliogenesis, these ~1.8-megadalton complexes are assembled in the cytoplasm and targeted to cilia by an unknown mechanism. Here, we used the ciliate
    MeSH term(s) Axonemal Dyneins/chemistry ; Axonemal Dyneins/genetics ; Axonemal Dyneins/metabolism ; Cilia/metabolism ; Cryoelectron Microscopy ; Cytoplasm/metabolism ; Gene Knockdown Techniques ; Image Processing, Computer-Assisted ; Microtubules/physiology ; Models, Molecular ; Movement ; Protein Binding ; Protein Conformation ; Protein Domains ; Protozoan Proteins/chemistry ; Protozoan Proteins/genetics ; Protozoan Proteins/metabolism ; Tetrahymena thermophila/genetics ; Tetrahymena thermophila/physiology
    Chemical Substances Protozoan Proteins ; Axonemal Dyneins (EC 3.6.4.2)
    Language English
    Publishing date 2020-12-13
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 128410-1
    ISSN 1095-9203 ; 0036-8075
    ISSN (online) 1095-9203
    ISSN 0036-8075
    DOI 10.1126/science.abe0526
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Cryo-EM structure of a licensed DNA replication origin

    Ferdos Abid Ali / Max E. Douglas / Julia Locke / Valerie E. Pye / Andrea Nans / John F. X. Diffley / Alessandro Costa

    Nature Communications, Vol 8, Iss 1, Pp 1-

    2017  Volume 10

    Abstract: Origins of replication are licensed by loading of MCM onto DNA, and origin firing depends on interaction with Cdc45 and GINS to form two CMG holo-helicases. Here, authors determine the cryo-EM structures of DNA-bound MCM and visualise a phospho-dependent ...

    Abstract Origins of replication are licensed by loading of MCM onto DNA, and origin firing depends on interaction with Cdc45 and GINS to form two CMG holo-helicases. Here, authors determine the cryo-EM structures of DNA-bound MCM and visualise a phospho-dependent MCM element important for Cdc45 recruitment.
    Keywords Science ; Q
    Language English
    Publishing date 2017-12-01T00:00:00Z
    Publisher Nature Publishing Group
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  7. Article ; Online: Cryo-EM structure of a licensed DNA replication origin

    Ferdos Abid Ali / Max E. Douglas / Julia Locke / Valerie E. Pye / Andrea Nans / John F. X. Diffley / Alessandro Costa

    Nature Communications, Vol 8, Iss 1, Pp 1-

    2017  Volume 10

    Abstract: Origins of replication are licensed by loading of MCM onto DNA, and origin firing depends on interaction with Cdc45 and GINS to form two CMG holo-helicases. Here, authors determine the cryo-EM structures of DNA-bound MCM and visualise a phospho-dependent ...

    Abstract Origins of replication are licensed by loading of MCM onto DNA, and origin firing depends on interaction with Cdc45 and GINS to form two CMG holo-helicases. Here, authors determine the cryo-EM structures of DNA-bound MCM and visualise a phospho-dependent MCM element important for Cdc45 recruitment.
    Keywords Science ; Q
    Language English
    Publishing date 2017-12-01T00:00:00Z
    Publisher Nature Portfolio
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  8. Article ; Online: Cryo-EM structure of a licensed DNA replication origin.

    Abid Ali, Ferdos / Douglas, Max E / Locke, Julia / Pye, Valerie E / Nans, Andrea / Diffley, John F X / Costa, Alessandro

    Nature communications

    2017  Volume 8, Issue 1, Page(s) 2241

    Abstract: Eukaryotic origins of replication are licensed upon loading of the MCM helicase motor onto DNA. ATP hydrolysis by MCM is required for loading and the post-catalytic MCM is an inactive double hexamer that encircles duplex DNA. Origin firing depends on MCM ...

    Abstract Eukaryotic origins of replication are licensed upon loading of the MCM helicase motor onto DNA. ATP hydrolysis by MCM is required for loading and the post-catalytic MCM is an inactive double hexamer that encircles duplex DNA. Origin firing depends on MCM engagement of Cdc45 and GINS to form the CMG holo-helicase. CMG assembly requires several steps including MCM phosphorylation by DDK. To understand origin activation, here we have determined the cryo-EM structures of DNA-bound MCM, either unmodified or phosphorylated, and visualize a phospho-dependent MCM element likely important for Cdc45 recruitment. MCM pore loops touch both the Watson and Crick strands, constraining duplex DNA in a bent configuration. By comparing our new MCM-DNA structure with the structure of CMG-DNA, we suggest how the conformational transition from the loaded, post-catalytic MCM to CMG might promote DNA untwisting and melting at the onset of replication.
    MeSH term(s) Cell Cycle Proteins/metabolism ; Cryoelectron Microscopy ; DNA/metabolism ; DNA/ultrastructure ; DNA Helicases ; DNA Replication ; DNA-Binding Proteins/metabolism ; DNA-Binding Proteins/ultrastructure ; Holoenzymes ; Image Processing, Computer-Assisted ; Minichromosome Maintenance Proteins/metabolism ; Minichromosome Maintenance Proteins/ultrastructure ; Nuclear Proteins/metabolism ; Nuclear Proteins/ultrastructure ; Nucleic Acid Conformation ; Phosphorylation ; Protein Conformation ; Protein Serine-Threonine Kinases/metabolism ; Protein Structure, Quaternary ; Saccharomyces cerevisiae ; Saccharomyces cerevisiae Proteins/metabolism ; Saccharomyces cerevisiae Proteins/ultrastructure
    Chemical Substances CDC45 protein, S cerevisiae ; Cell Cycle Proteins ; DNA-Binding Proteins ; Holoenzymes ; Nuclear Proteins ; Saccharomyces cerevisiae Proteins ; DNA (9007-49-2) ; CDC7 protein, S cerevisiae (EC 2.7.1.-) ; Protein Serine-Threonine Kinases (EC 2.7.11.1) ; DNA Helicases (EC 3.6.4.-) ; Minichromosome Maintenance Proteins (EC 3.6.4.12)
    Language English
    Publishing date 2017-12-21
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2553671-0
    ISSN 2041-1723 ; 2041-1723
    ISSN (online) 2041-1723
    ISSN 2041-1723
    DOI 10.1038/s41467-017-02389-0
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: CMG-Pol epsilon dynamics suggests a mechanism for the establishment of leading-strand synthesis in the eukaryotic replisome.

    Zhou, Jin Chuan / Janska, Agnieszka / Goswami, Panchali / Renault, Ludovic / Abid Ali, Ferdos / Kotecha, Abhay / Diffley, John F X / Costa, Alessandro

    Proceedings of the National Academy of Sciences of the United States of America

    2017  Volume 114, Issue 16, Page(s) 4141–4146

    Abstract: The replisome unwinds and synthesizes DNA for genome duplication. In eukaryotes, the Cdc45-MCM-GINS (CMG) helicase and the leading-strand polymerase, Pol epsilon, form a stable assembly. The mechanism for coupling DNA unwinding with synthesis is starting ...

    Abstract The replisome unwinds and synthesizes DNA for genome duplication. In eukaryotes, the Cdc45-MCM-GINS (CMG) helicase and the leading-strand polymerase, Pol epsilon, form a stable assembly. The mechanism for coupling DNA unwinding with synthesis is starting to be elucidated, however the architecture and dynamics of the replication fork remain only partially understood, preventing a molecular understanding of chromosome replication. To address this issue, we conducted a systematic single-particle EM study on multiple permutations of the reconstituted CMG-Pol epsilon assembly. Pol epsilon contains two flexibly tethered lobes. The noncatalytic lobe is anchored to the motor of the helicase, whereas the polymerization domain extends toward the side of the helicase. We observe two alternate configurations of the DNA synthesis domain in the CMG-bound Pol epsilon. We propose that this conformational switch might control DNA template engagement and release, modulating replisome progression.
    MeSH term(s) DNA Helicases/genetics ; DNA Helicases/metabolism ; DNA Polymerase II/genetics ; DNA Polymerase II/metabolism ; DNA Replication ; Eukaryotic Cells/metabolism ; Saccharomyces cerevisiae/enzymology ; Saccharomyces cerevisiae/genetics ; Saccharomyces cerevisiae/growth & development ; Saccharomyces cerevisiae Proteins/genetics ; Saccharomyces cerevisiae Proteins/metabolism
    Chemical Substances Saccharomyces cerevisiae Proteins ; DNA Polymerase II (EC 2.7.7.7) ; DNA Helicases (EC 3.6.4.-)
    Language English
    Publishing date 2017-04-03
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.1700530114
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Molecular Basis for ATP-Hydrolysis-Driven DNA Translocation by the CMG Helicase of the Eukaryotic Replisome

    Patrik Eickhoff / Hazal B. Kose / Fabrizio Martino / Tatjana Petojevic / Ferdos Abid Ali / Julia Locke / Nele Tamberg / Andrea Nans / James M. Berger / Michael R. Botchan / Hasan Yardimci / Alessandro Costa

    Cell Reports, Vol 28, Iss 10, Pp 2673-2688.e

    2019  Volume 8

    Abstract: Summary: In the eukaryotic replisome, DNA unwinding by the Cdc45-MCM-Go-Ichi-Ni-San (GINS) (CMG) helicase requires a hexameric ring-shaped ATPase named minichromosome maintenance (MCM), which spools single-stranded DNA through its central channel. Not ... ...

    Abstract Summary: In the eukaryotic replisome, DNA unwinding by the Cdc45-MCM-Go-Ichi-Ni-San (GINS) (CMG) helicase requires a hexameric ring-shaped ATPase named minichromosome maintenance (MCM), which spools single-stranded DNA through its central channel. Not all six ATPase sites are required for unwinding; however, the helicase mechanism is unknown. We imaged ATP-hydrolysis-driven translocation of the CMG using cryo-electron microscopy (cryo-EM) and found that the six MCM subunits engage DNA using four neighboring protomers at a time, with ATP binding promoting DNA engagement. Morphing between different helicase states leads us to suggest a non-symmetric hand-over-hand rotary mechanism, explaining the asymmetric requirements of ATPase function around the MCM ring of the CMG. By imaging of a higher-order replisome assembly, we find that the Mrc1-Csm3-Tof1 fork-stabilization complex strengthens the interaction between parental duplex DNA and the CMG at the fork, which might support the coupling between DNA translocation and fork unwinding. : Eickhoff et al. used cryo-EM to image DNA unwinding by the eukaryotic replicative helicase, Cdc45-MCM-GINS. As the hexameric MCM ring hydrolyses ATP, DNA is spooled asymmetrically around the ring pore. This asymmetry explains why selected ATPase sites are essential for DNA translocation. Understanding DNA unwinding informs on replication fork progression. Keywords: DNA replication, cryo-EM, AAA+ ATPase, helicase, molecular motor, DNA unwinding
    Keywords Biology (General) ; QH301-705.5
    Subject code 612
    Language English
    Publishing date 2019-09-01T00:00:00Z
    Publisher Elsevier
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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