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Dai J, Liu R, He S, Li T, Hu Y, Huang H, Li Y, Guo X. The Role of SF1 and SF2 Helicases in Biotechnological Applications. Appl Biochem Biotechnol 2024:10.1007/s12010-024-05027-w. [PMID: 39093351 DOI: 10.1007/s12010-024-05027-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/23/2024] [Indexed: 08/04/2024]
Abstract
Helicases, which utilize ATP hydrolysis to separate nucleic acid duplexes, play crucial roles in DNA and RNA replication, repair, recombination, and transcription. Categorized into the major groups superfamily 1 (SF1) and superfamily 2 (SF2), alongside four minor groups, these proteins exhibit a conserved catalytic core indicative of a shared evolutionary origin while displaying functional diversity through interactions with various substrates. This review summarizes the structures, functions and mechanisms of SF1 and SF2 helicases, with an emphasis on conserved ATPase sites and RecA-like domains essential for their enzymatic and nucleic acid binding capabilities. It highlights the unique 1B and 2B domains in SF1 helicases and their impact on enzymatic activity. The DNA unwinding process is detailed, covering substrate recognition, ATP hydrolysis, and conformational changes, while addressing debates over the active form of UvrD helicase and post-unwinding dissociation. More importantly, this review discusses the biotechnological potential of helicases in emerging technologies such as nanopore sequencing, protein sequencing, and isothermal amplification, focusing on their use in pathogen detection, biosensor enhancement, and cancer treatment. As understanding deepens, innovative applications in genome editing, DNA sequencing, and synthetic biology are anticipated.
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Affiliation(s)
- Jing Dai
- Dongguan Key Laboratory of Public Health Laboratory Science, School of Public Health, Guangdong Medical University, Dongguan, 523808, People's Republic of China
| | - Ronghui Liu
- School of Microelectronic, Southern University of Science and Technology, Shenzhen, 518000, People's Republic of China.
| | - Shujun He
- Dongguan Key Laboratory of Public Health Laboratory Science, School of Public Health, Guangdong Medical University, Dongguan, 523808, People's Republic of China
| | - Tie Li
- School of Microelectronic, Southern University of Science and Technology, Shenzhen, 518000, People's Republic of China
| | - Yuhang Hu
- School of Microelectronic, Southern University of Science and Technology, Shenzhen, 518000, People's Republic of China
| | - Huiqun Huang
- Dongguan Key Laboratory of Public Health Laboratory Science, School of Public Health, Guangdong Medical University, Dongguan, 523808, People's Republic of China
| | - Yi Li
- School of Microelectronic, Southern University of Science and Technology, Shenzhen, 518000, People's Republic of China.
| | - Xinrong Guo
- Dongguan Key Laboratory of Public Health Laboratory Science, School of Public Health, Guangdong Medical University, Dongguan, 523808, People's Republic of China.
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2
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Henrikus SS, Gross MH, Willhoft O, Pühringer T, Lewis JS, McClure AW, Greiwe JF, Palm G, Nans A, Diffley JFX, Costa A. Unwinding of a eukaryotic origin of replication visualized by cryo-EM. Nat Struct Mol Biol 2024; 31:1265-1276. [PMID: 38760633 PMCID: PMC11327109 DOI: 10.1038/s41594-024-01280-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Accepted: 03/19/2024] [Indexed: 05/19/2024]
Abstract
To prevent detrimental chromosome re-replication, DNA loading of a double hexamer of the minichromosome maintenance (MCM) replicative helicase is temporally separated from DNA unwinding. Upon S-phase transition in yeast, DNA unwinding is achieved in two steps: limited opening of the double helix and topological separation of the two DNA strands. First, Cdc45, GINS and Polε engage MCM to assemble a double CMGE with two partially separated hexamers that nucleate DNA melting. In the second step, triggered by Mcm10, two CMGEs separate completely, eject the lagging-strand template and cross paths. To understand Mcm10 during helicase activation, we used biochemical reconstitution with cryogenic electron microscopy. We found that Mcm10 splits the double CMGE by engaging the N-terminal homo-dimerization face of MCM. To eject the lagging strand, DNA unwinding is started from the N-terminal side of MCM while the hexamer channel becomes too narrow to harbor duplex DNA.
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Affiliation(s)
- Sarah S Henrikus
- Macromolecular Machines Laboratory, Francis Crick Institute, London, UK
- Genome Stability Unit, St. Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia
| | - Marta H Gross
- Chromosome Replication Laboratory, Francis Crick Institute, London, UK
| | - Oliver Willhoft
- Macromolecular Machines Laboratory, Francis Crick Institute, London, UK
| | - Thomas Pühringer
- Macromolecular Machines Laboratory, Francis Crick Institute, London, UK
| | - Jacob S Lewis
- Macromolecular Machines Laboratory, Francis Crick Institute, London, UK
| | - Allison W McClure
- Chromosome Replication Laboratory, Francis Crick Institute, London, UK
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Julia F Greiwe
- Macromolecular Machines Laboratory, Francis Crick Institute, London, UK
| | - Giacomo Palm
- Macromolecular Machines Laboratory, Francis Crick Institute, London, UK
| | - Andrea Nans
- Structural Biology Science Technology Platform, Francis Crick Institute, London, UK
| | - John F X Diffley
- Chromosome Replication Laboratory, Francis Crick Institute, London, UK
| | - Alessandro Costa
- Macromolecular Machines Laboratory, Francis Crick Institute, London, UK.
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3
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Acharya A, Bret H, Huang JW, Mütze M, Göse M, Kissling VM, Seidel R, Ciccia A, Guérois R, Cejka P. Mechanism of DNA unwinding by MCM8-9 in complex with HROB. Nat Commun 2024; 15:3584. [PMID: 38678026 PMCID: PMC11055865 DOI: 10.1038/s41467-024-47936-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Accepted: 04/15/2024] [Indexed: 04/29/2024] Open
Abstract
HROB promotes the MCM8-9 helicase in DNA damage response. To understand how HROB activates MCM8-9, we defined their interaction interface. We showed that HROB makes important yet transient contacts with both MCM8 and MCM9, and binds the MCM8-9 heterodimer with the highest affinity. MCM8-9-HROB prefer branched DNA structures, and display low DNA unwinding processivity. MCM8-9 unwinds DNA as a hexamer that assembles from dimers on DNA in the presence of ATP. The hexamer involves two repeating protein-protein interfaces between the alternating MCM8 and MCM9 subunits. One of these interfaces is quite stable and forms an obligate heterodimer across which HROB binds. The other interface is labile and mediates hexamer assembly, independently of HROB. The ATPase site formed at the labile interface contributes disproportionally more to DNA unwinding than that at the stable interface. Here, we show that HROB promotes DNA unwinding downstream of MCM8-9 loading and ring formation on ssDNA.
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Affiliation(s)
- Ananya Acharya
- Institute for Research in Biomedicine, Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, Bellinzona, 6500, Switzerland
- Department of Biology, Institute of Biochemistry, Eidgenössische Technische Hochschule (ETH), Zürich, 8093, Switzerland
| | - Hélène Bret
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France
| | - Jen-Wei Huang
- Department of Genetics and Development, Institute for Cancer Genetics, Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY, USA
| | - Martin Mütze
- Peter Debye Institute for Soft Matter Physics, Universität Leipzig, Leipzig, 04103, Germany
| | - Martin Göse
- Peter Debye Institute for Soft Matter Physics, Universität Leipzig, Leipzig, 04103, Germany
| | - Vera Maria Kissling
- Department of Biology, Institute of Biochemistry, Eidgenössische Technische Hochschule (ETH), Zürich, 8093, Switzerland
- Particles-Biology Interactions Laboratory, Department of Materials Meet Life, Swiss Federal Laboratories for Materials Science and Technology (Empa), St. Gallen, 9014, Switzerland
| | - Ralf Seidel
- Peter Debye Institute for Soft Matter Physics, Universität Leipzig, Leipzig, 04103, Germany
| | - Alberto Ciccia
- Department of Genetics and Development, Institute for Cancer Genetics, Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY, USA
| | - Raphaël Guérois
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France.
| | - Petr Cejka
- Institute for Research in Biomedicine, Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, Bellinzona, 6500, Switzerland.
- Department of Biology, Institute of Biochemistry, Eidgenössische Technische Hochschule (ETH), Zürich, 8093, Switzerland.
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4
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Day M, Tetik B, Parlak M, Almeida-Hernández Y, Räschle M, Kaschani F, Siegert H, Marko A, Sanchez-Garcia E, Kaiser M, Barker IA, Pearl LH, Oliver AW, Boos D. TopBP1 utilises a bipartite GINS binding mode to support genome replication. Nat Commun 2024; 15:1797. [PMID: 38413589 PMCID: PMC10899662 DOI: 10.1038/s41467-024-45946-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 02/07/2024] [Indexed: 02/29/2024] Open
Abstract
Activation of the replicative Mcm2-7 helicase by loading GINS and Cdc45 is crucial for replication origin firing, and as such for faithful genetic inheritance. Our biochemical and structural studies demonstrate that the helicase activator GINS interacts with TopBP1 through two separate binding surfaces, the first involving a stretch of highly conserved amino acids in the TopBP1-GINI region, the second a surface on TopBP1-BRCT4. The two surfaces bind to opposite ends of the A domain of the GINS subunit Psf1. Mutation analysis reveals that either surface is individually able to support TopBP1-GINS interaction, albeit with reduced affinity. Consistently, either surface is sufficient for replication origin firing in Xenopus egg extracts and becomes essential in the absence of the other. The TopBP1-GINS interaction appears sterically incompatible with simultaneous binding of DNA polymerase epsilon (Polε) to GINS when bound to Mcm2-7-Cdc45, although TopBP1-BRCT4 and the Polε subunit PolE2 show only partial competitivity in binding to Psf1. Our TopBP1-GINS model improves the understanding of the recently characterised metazoan pre-loading complex. It further predicts the coordination of three molecular origin firing processes, DNA polymerase epsilon arrival, TopBP1 ejection and GINS integration into Mcm2-7-Cdc45.
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Affiliation(s)
- Matthew Day
- School of Biological and Behavioural Sciences, Blizard Institute, Queen Mary University of London, London, E1 2AT, UK.
- Cancer Research UK DNA Repair Enzymes Group, Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton, BN1 9RQ, UK.
| | - Bilal Tetik
- Molecular Genetics II, Center of Medical Biotechnology, University of Duisburg-Essen, Universitätsstraße 2-5, 45141, Essen, Germany
| | - Milena Parlak
- Molecular Genetics II, Center of Medical Biotechnology, University of Duisburg-Essen, Universitätsstraße 2-5, 45141, Essen, Germany
| | - Yasser Almeida-Hernández
- Computational Bioengineering, Fakultät Bio- und Chemieingenieurwesen, Technical University Dortmund, Emil-Figge Str. 66, 44227, Dortmund, Germany
- Computational Biochemistry, Center of Medical Biotechnology, University of Duisburg-Essen, Universitätsstraße 2-5, 45141, Essen, Germany
| | - Markus Räschle
- Molecular Genetics, Technical University Kaiserslautern, Paul-Ehrlich Straße 24, 67663, Kaiserslautern, Germany
| | - Farnusch Kaschani
- Analytics Core Facility Essen, Center of Medical Biotechnology, University of Duisburg-Essen, Universitätsstraße 2-5, 45141, Essen, Germany
- Chemical Biology, Center of Medical Biotechnology, University Duisburg-Essen, Fakultät Biologie, Essen, Germany
| | - Heike Siegert
- Molecular Genetics II, Center of Medical Biotechnology, University of Duisburg-Essen, Universitätsstraße 2-5, 45141, Essen, Germany
| | - Anika Marko
- Molecular Genetics II, Center of Medical Biotechnology, University of Duisburg-Essen, Universitätsstraße 2-5, 45141, Essen, Germany
| | - Elsa Sanchez-Garcia
- Computational Bioengineering, Fakultät Bio- und Chemieingenieurwesen, Technical University Dortmund, Emil-Figge Str. 66, 44227, Dortmund, Germany
- Computational Biochemistry, Center of Medical Biotechnology, University of Duisburg-Essen, Universitätsstraße 2-5, 45141, Essen, Germany
| | - Markus Kaiser
- Analytics Core Facility Essen, Center of Medical Biotechnology, University of Duisburg-Essen, Universitätsstraße 2-5, 45141, Essen, Germany
- Chemical Biology, Center of Medical Biotechnology, University Duisburg-Essen, Fakultät Biologie, Essen, Germany
| | - Isabel A Barker
- Cancer Research UK DNA Repair Enzymes Group, Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton, BN1 9RQ, UK
| | - Laurence H Pearl
- Cancer Research UK DNA Repair Enzymes Group, Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton, BN1 9RQ, UK.
- Division of Structural Biology, Institute of Cancer Research, Chester Beatty Laboratories, 237 Fulham Road, London, SW1E 6BT, UK.
| | - Antony W Oliver
- Cancer Research UK DNA Repair Enzymes Group, Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton, BN1 9RQ, UK.
| | - Dominik Boos
- Molecular Genetics II, Center of Medical Biotechnology, University of Duisburg-Essen, Universitätsstraße 2-5, 45141, Essen, Germany.
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5
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Cvetkovic MA, Passaretti P, Butryn A, Reynolds-Winczura A, Kingsley G, Skagia A, Fernandez-Cuesta C, Poovathumkadavil D, George R, Chauhan AS, Jhujh SS, Stewart GS, Gambus A, Costa A. The structural mechanism of dimeric DONSON in replicative helicase activation. Mol Cell 2023; 83:4017-4031.e9. [PMID: 37820732 DOI: 10.1016/j.molcel.2023.09.029] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 09/15/2023] [Accepted: 09/25/2023] [Indexed: 10/13/2023]
Abstract
The MCM motor of the replicative helicase is loaded onto origin DNA as an inactive double hexamer before replication initiation. Recruitment of activators GINS and Cdc45 upon S-phase transition promotes the assembly of two active CMG helicases. Although work with yeast established the mechanism for origin activation, how CMG is formed in higher eukaryotes is poorly understood. Metazoan Downstream neighbor of Son (DONSON) has recently been shown to deliver GINS to MCM during CMG assembly. What impact this has on the MCM double hexamer is unknown. Here, we used cryoelectron microscopy (cryo-EM) on proteins isolated from replicating Xenopus egg extracts to identify a double CMG complex bridged by a DONSON dimer. We find that tethering elements mediating complex formation are essential for replication. DONSON reconfigures the MCM motors in the double CMG, and primordial dwarfism patients' mutations disrupting DONSON dimerization affect GINS and MCM engagement in human cells and DNA synthesis in Xenopus egg extracts.
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Affiliation(s)
- Milos A Cvetkovic
- Macromolecular Machines Laboratory, The Francis Crick Institute, London NW1 1AT, UK
| | - Paolo Passaretti
- Institute of Cancer and Genomic Sciences, Birmingham Centre for Genome Biology, University of Birmingham, Birmingham B15 2TT, UK
| | - Agata Butryn
- Macromolecular Machines Laboratory, The Francis Crick Institute, London NW1 1AT, UK
| | - Alicja Reynolds-Winczura
- Institute of Cancer and Genomic Sciences, Birmingham Centre for Genome Biology, University of Birmingham, Birmingham B15 2TT, UK
| | - Georgia Kingsley
- Institute of Cancer and Genomic Sciences, Birmingham Centre for Genome Biology, University of Birmingham, Birmingham B15 2TT, UK
| | - Aggeliki Skagia
- Institute of Cancer and Genomic Sciences, Birmingham Centre for Genome Biology, University of Birmingham, Birmingham B15 2TT, UK
| | - Cyntia Fernandez-Cuesta
- Institute of Cancer and Genomic Sciences, Birmingham Centre for Genome Biology, University of Birmingham, Birmingham B15 2TT, UK
| | - Divyasree Poovathumkadavil
- Institute of Cancer and Genomic Sciences, Birmingham Centre for Genome Biology, University of Birmingham, Birmingham B15 2TT, UK
| | - Roger George
- Structural Biology Science Technology Platform, The Francis Crick Institute, London NW1 1AT, UK
| | - Anoop S Chauhan
- Institute of Cancer and Genomic Sciences, Birmingham Centre for Genome Biology, University of Birmingham, Birmingham B15 2TT, UK
| | - Satpal S Jhujh
- Institute of Cancer and Genomic Sciences, Birmingham Centre for Genome Biology, University of Birmingham, Birmingham B15 2TT, UK
| | - Grant S Stewart
- Institute of Cancer and Genomic Sciences, Birmingham Centre for Genome Biology, University of Birmingham, Birmingham B15 2TT, UK
| | - Agnieszka Gambus
- Institute of Cancer and Genomic Sciences, Birmingham Centre for Genome Biology, University of Birmingham, Birmingham B15 2TT, UK.
| | - Alessandro Costa
- Macromolecular Machines Laboratory, The Francis Crick Institute, London NW1 1AT, UK.
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6
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Bellani MA, Shaik A, Majumdar I, Ling C, Seidman MM. The Response of the Replication Apparatus to Leading Template Strand Blocks. Cells 2023; 12:2607. [PMID: 37998342 PMCID: PMC10670059 DOI: 10.3390/cells12222607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 11/07/2023] [Accepted: 11/08/2023] [Indexed: 11/25/2023] Open
Abstract
Duplication of the genome requires the replication apparatus to overcome a variety of impediments, including covalent DNA adducts, the most challenging of which is on the leading template strand. Replisomes consist of two functional units, a helicase to unwind DNA and polymerases to synthesize it. The helicase is a multi-protein complex that encircles the leading template strand and makes the first contact with a leading strand adduct. The size of the channel in the helicase would appear to preclude transit by large adducts such as DNA: protein complexes (DPC). Here we discuss some of the extensively studied pathways that support replication restart after replisome encounters with leading template strand adducts. We also call attention to recent work that highlights the tolerance of the helicase for adducts ostensibly too large to pass through the central channel.
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Affiliation(s)
| | | | | | | | - Michael M. Seidman
- Laboratory of Molecular Biology and Immunology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA; (M.A.B.)
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7
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Turgeman-Grott I, Arsenault D, Yahav D, Feng Y, Miezner G, Naki D, Peri O, Papke RT, Gogarten JP, Gophna U. Neighboring inteins interfere with one another's homing capacity. PNAS NEXUS 2023; 2:pgad354. [PMID: 38024399 PMCID: PMC10643990 DOI: 10.1093/pnasnexus/pgad354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 10/16/2023] [Accepted: 10/25/2023] [Indexed: 12/01/2023]
Abstract
Inteins are mobile genetic elements that invade conserved genes across all domains of life and viruses. In some instances, a single gene will have several intein insertion sites. In Haloarchaea, the minichromosome maintenance (MCM) protein at the core of replicative DNA helicase contains four intein insertion sites within close proximity, where two of these sites (MCM-a and MCM-d) are more likely to be invaded. A haloarchaeon that harbors both MCM-a and MCM-d inteins, Haloferax mediterranei, was studied in vivo to determine intein invasion dynamics and the interactions between neighboring inteins. Additionally, invasion frequencies and the conservation of insertion site sequences in 129 Haloferacales mcm homologs were analyzed to assess intein distribution across the order. We show that the inteins at MCM-a and MCM-d recognize and cleave their respective target sites and, in the event that only one empty intein invasion site is present, readily initiate homing (i.e. single homing). However, when two inteins are present co-homing into an intein-free target sequence is much less effective. The two inteins are more effective when invading alleles that already contain an intein at one of the two sites. Our in vivo and computational studies also support that having a proline in place of a serine as the first C-terminal extein residue of the MCM-d insertion site prevents successful intein splicing, but does not stop recognition of the insertion site by the intein's homing endonuclease.
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Affiliation(s)
- Israela Turgeman-Grott
- The Shmunis School of Biomedicine and Cancer Research, Faculty of Life Sciences, Tel Aviv University, P.O. Box 39040, 6997801 Tel Aviv, Israel
| | - Danielle Arsenault
- Department of Molecular and Cell Biology, University of Connecticut, 91 North Eagleville Road, Storrs, CT 06268-3125, USA
| | - Dekel Yahav
- The Shmunis School of Biomedicine and Cancer Research, Faculty of Life Sciences, Tel Aviv University, P.O. Box 39040, 6997801 Tel Aviv, Israel
| | - Yutian Feng
- Department of Molecular and Cell Biology, University of Connecticut, 91 North Eagleville Road, Storrs, CT 06268-3125, USA
| | - Guy Miezner
- The Shmunis School of Biomedicine and Cancer Research, Faculty of Life Sciences, Tel Aviv University, P.O. Box 39040, 6997801 Tel Aviv, Israel
| | - Doron Naki
- The Shmunis School of Biomedicine and Cancer Research, Faculty of Life Sciences, Tel Aviv University, P.O. Box 39040, 6997801 Tel Aviv, Israel
| | - Omri Peri
- The Shmunis School of Biomedicine and Cancer Research, Faculty of Life Sciences, Tel Aviv University, P.O. Box 39040, 6997801 Tel Aviv, Israel
| | - R Thane Papke
- Department of Molecular and Cell Biology, University of Connecticut, 91 North Eagleville Road, Storrs, CT 06268-3125, USA
| | - Johann Peter Gogarten
- Department of Molecular and Cell Biology, University of Connecticut, 91 North Eagleville Road, Storrs, CT 06268-3125, USA
- Institute for Systems Genomics, University of Connecticut, 67 North Eagleville Road, Storrs, CT 06268-3003, USA
| | - Uri Gophna
- The Shmunis School of Biomedicine and Cancer Research, Faculty of Life Sciences, Tel Aviv University, P.O. Box 39040, 6997801 Tel Aviv, Israel
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8
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Xu Z, Feng J, Yu D, Huo Y, Ma X, Lam WH, Liu Z, Li XD, Ishibashi T, Dang S, Zhai Y. Synergism between CMG helicase and leading strand DNA polymerase at replication fork. Nat Commun 2023; 14:5849. [PMID: 37730685 PMCID: PMC10511561 DOI: 10.1038/s41467-023-41506-0] [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: 12/21/2021] [Accepted: 09/07/2023] [Indexed: 09/22/2023] Open
Abstract
The replisome that replicates the eukaryotic genome consists of at least three engines: the Cdc45-MCM-GINS (CMG) helicase that separates duplex DNA at the replication fork and two DNA polymerases, one on each strand, that replicate the unwound DNA. Here, we determined a series of cryo-electron microscopy structures of a yeast replisome comprising CMG, leading-strand polymerase Polε and three accessory factors on a forked DNA. In these structures, Polε engages or disengages with the motor domains of the CMG by occupying two alternative positions, which closely correlate with the rotational movement of the single-stranded DNA around the MCM pore. During this process, the polymerase remains stably coupled to the helicase using Psf1 as a hinge. This synergism is modulated by a concerted rearrangement of ATPase sites to drive DNA translocation. The Polε-MCM coupling is not only required for CMG formation to initiate DNA replication but also facilitates the leading-strand DNA synthesis mediated by Polε. Our study elucidates a mechanism intrinsic to the replisome that coordinates the activities of CMG and Polε to negotiate any roadblocks, DNA damage, and epigenetic marks encountered during translocation along replication forks.
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Affiliation(s)
- Zhichun Xu
- School of Biological Sciences, The University of Hong Kong, Hong Kong, China
| | - Jianrong Feng
- Division of Life Science, The Hong Kong University of Science & Technology, Hong Kong, China
| | - Daqi Yu
- Division of Life Science, The Hong Kong University of Science & Technology, Hong Kong, China
| | - Yunjing Huo
- School of Biological Sciences, The University of Hong Kong, Hong Kong, China
| | - Xiaohui Ma
- Division of Life Science, The Hong Kong University of Science & Technology, Hong Kong, China
| | - Wai Hei Lam
- School of Biological Sciences, The University of Hong Kong, Hong Kong, China
| | - Zheng Liu
- Department of Chemistry, The University of Hong Kong, Hong Kong, China
| | - Xiang David Li
- Department of Chemistry, The University of Hong Kong, Hong Kong, China
| | - Toyotaka Ishibashi
- Division of Life Science, The Hong Kong University of Science & Technology, Hong Kong, China
| | - Shangyu Dang
- Division of Life Science, The Hong Kong University of Science & Technology, Hong Kong, China.
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China.
- HKUST-Shenzhen Research Institute, 518057, Nanshan, Shenzhen, China.
| | - Yuanliang Zhai
- School of Biological Sciences, The University of Hong Kong, Hong Kong, China.
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9
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McKinzey DR, Li C, Gao Y, Trakselis MA. Activity, substrate preference and structure of the HsMCM8/9 helicase. Nucleic Acids Res 2023; 51:7330-7341. [PMID: 37309874 PMCID: PMC10415141 DOI: 10.1093/nar/gkad508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 05/25/2023] [Accepted: 05/31/2023] [Indexed: 06/14/2023] Open
Abstract
The minichromosomal maintenance proteins, MCM8 and MCM9, are more recent evolutionary additions to the MCM family, only cooccurring in selected higher eukaryotes. Mutations in these genes are directly linked to ovarian insufficiency, infertility, and several cancers. MCM8/9 appears to have ancillary roles in fork progression and recombination of broken replication forks. However, the biochemical activity, specificities and structures have not been adequately illustrated, making mechanistic determination difficult. Here, we show that human MCM8/9 (HsMCM8/9) is an ATP dependent DNA helicase that unwinds fork DNA substrates with a 3'-5' polarity. High affinity ssDNA binding occurs in the presence of nucleoside triphosphates, while ATP hydrolysis weakens the interaction with DNA. The cryo-EM structure of the HsMCM8/9 heterohexamer was solved at 4.3 Å revealing a trimer of heterodimer configuration with two types of interfacial AAA+ nucleotide binding sites that become more organized upon binding ADP. Local refinements of the N or C-terminal domains (NTD or CTD) improved the resolution to 3.9 or 4.1 Å, respectively, and shows a large displacement in the CTD. Changes in AAA+ CTD upon nucleotide binding and a large swing between the NTD and CTD likely implies that MCM8/9 utilizes a sequential subunit translocation mechanism for DNA unwinding.
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Affiliation(s)
- David R McKinzey
- Department of Chemistry and Biochemistry, Baylor University, Waco, TX 76706, USA
| | - Chuxuan Li
- Department of Biosciences, Rice University, Houston, TX 77005, USA
| | - Yang Gao
- Department of Biosciences, Rice University, Houston, TX 77005, USA
| | - Michael A Trakselis
- Department of Chemistry and Biochemistry, Baylor University, Waco, TX 76706, USA
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10
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Acharya A, Bret H, Huang JW, Mütze M, Göse M, Kissling V, Seidel R, Ciccia A, Guérois R, Cejka P. Mechanism of DNA unwinding by hexameric MCM8-9 in complex with HROB. RESEARCH SQUARE 2023:rs.3.rs-3054483. [PMID: 37461676 PMCID: PMC10350107 DOI: 10.21203/rs.3.rs-3054483/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/24/2023]
Abstract
The human MCM8-9 helicase functions in concert with HROB in the context of homologous recombination, but its precise function is unknown. To gain insights into how HROB regulates MCM8-9, we first used molecular modeling and biochemistry to define their interaction interface. We show that HROB makes important contacts with both MCM8 and MCM9 subunits, which directly promotes its DNA-dependent ATPase and helicase activities. MCM8-9-HROB preferentially binds and unwinds branched DNA structures, and single-molecule experiments reveal a low DNA unwinding processivity. MCM8-9 unwinds DNA as a hexameric complex that assembles from dimers on DNA in the presence of ATP, which is prerequisite for its helicase function. The hexamer formation thus involves two repeating protein-protein interfaces forming between the alternating MCM8 and MCM9 subunits. One of these interfaces is rather stable and forms an obligate heterodimer, while the other interface is labile and mediates the assembly of the hexamer on DNA, independently of HROB. The ATPase site composed of the subunits forming the labile interface disproportionally contributes to DNA unwinding. HROB does not affect the MCM8-9 ring formation, but promotes DNA unwinding downstream by possibly coordinating ATP hydrolysis with structural transitions accompanying translocation of MCM8-9 on DNA.
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Affiliation(s)
- Ananya Acharya
- Institute for Research in Biomedicine, Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, Bellinzona, 6500, Switzerland
- Department of Biology, Institute of Biochemistry, Eidgenössische Technische Hochschule (ETH), Zürich, 8093, Switzerland
| | - Hélène Bret
- Institute for Integrative Biology of the Cell (I2BC), Commissariat à l’Energie Atomique, Centre National de la Recherche Scientifique, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, 91190, France
| | - Jen-Wei Huang
- Department of Genetics and Development, Institute for Cancer Genetics, Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY, USA
| | - Martin Mütze
- Peter Debye Institute for Soft Matter Physics, Universität Leipzig, Leipzig, 04103, Germany
| | - Martin Göse
- Peter Debye Institute for Soft Matter Physics, Universität Leipzig, Leipzig, 04103, Germany
| | - Vera Kissling
- Department of Biology, Institute of Biochemistry, Eidgenössische Technische Hochschule (ETH), Zürich, 8093, Switzerland
| | - Ralf Seidel
- Peter Debye Institute for Soft Matter Physics, Universität Leipzig, Leipzig, 04103, Germany
| | - Alberto Ciccia
- Department of Genetics and Development, Institute for Cancer Genetics, Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY, USA
| | - Raphaël Guérois
- Institute for Integrative Biology of the Cell (I2BC), Commissariat à l’Energie Atomique, Centre National de la Recherche Scientifique, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, 91190, France
| | - Petr Cejka
- Institute for Research in Biomedicine, Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, Bellinzona, 6500, Switzerland
- Department of Biology, Institute of Biochemistry, Eidgenössische Technische Hochschule (ETH), Zürich, 8093, Switzerland
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11
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Acharya A, Bret H, Huang JW, Mütze M, Göse M, Kissling V, Seidel R, Ciccia A, Guérois R, Cejka P. Mechanism of DNA unwinding by hexameric MCM8-9 in complex with HROB. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.12.544631. [PMID: 37398313 PMCID: PMC10312610 DOI: 10.1101/2023.06.12.544631] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
The human MCM8-9 helicase functions in concert with HROB in the context of homologous recombination, but its precise function is unknown. To gain insights into how HROB regulates MCM8-9, we first used molecular modeling and biochemistry to define their interaction interface. We show that HROB makes important contacts with both MCM8 and MCM9 subunits, which directly promotes its DNA-dependent ATPase and helicase activities. MCM8-9-HROB preferentially binds and unwinds branched DNA structures, and single-molecule experiments reveal a low DNA unwinding processivity. MCM8-9 unwinds DNA as a hexameric complex that assembles from dimers on DNA in the presence of ATP, which is prerequisite for its helicase function. The hexamer formation thus involves two repeating protein-protein interfaces forming between the alternating MCM8 and MCM9 subunits. One of these interfaces is rather stable and forms an obligate heterodimer, while the other interface is labile and mediates the assembly of the hexamer on DNA, independently of HROB. The ATPase site composed of the subunits forming the labile interface disproportionally contributes to DNA unwinding. HROB does not affect the MCM8-9 ring formation, but promotes DNA unwinding downstream by possibly coordinating ATP hydrolysis with structural transitions accompanying translocation of MCM8-9 on DNA.
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12
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Smits DJ, Schot R, Popescu CA, Dias KR, Ades L, Briere LC, Sweetser DA, Kushima I, Aleksic B, Khan S, Karageorgou V, Ordonez N, Sleutels FJGT, van der Kaay DCM, Van Mol C, Van Esch H, Bertoli-Avella AM, Roscioli T, Mancini GMS. De novo MCM6 variants in neurodevelopmental disorders: a recognizable phenotype related to zinc binding residues. Hum Genet 2023:10.1007/s00439-023-02569-7. [PMID: 37198333 DOI: 10.1007/s00439-023-02569-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Accepted: 05/03/2023] [Indexed: 05/19/2023]
Abstract
The minichromosome maintenance (MCM) complex acts as a DNA helicase during DNA replication, and thereby regulates cell cycle progression and proliferation. In addition, MCM-complex components localize to centrosomes and play an independent role in ciliogenesis. Pathogenic variants in genes coding for MCM components and other DNA replication factors have been linked to growth and developmental disorders as Meier-Gorlin syndrome and Seckel syndrome. Trio exome/genome sequencing identified the same de novo MCM6 missense variant p.(Cys158Tyr) in two unrelated individuals that presented with overlapping phenotypes consisting of intra-uterine growth retardation, short stature, congenital microcephaly, endocrine features, developmental delay and urogenital anomalies. The identified variant affects a zinc binding cysteine in the MCM6 zinc finger signature. This domain, and specifically cysteine residues, are essential for MCM-complex dimerization and the induction of helicase activity, suggesting a deleterious effect of this variant on DNA replication. Fibroblasts derived from the two affected individuals showed defects both in ciliogenesis and cell proliferation. We additionally traced three unrelated individuals with de novo MCM6 variants in the oligonucleotide binding (OB)-fold domain, presenting with variable (neuro)developmental features including autism spectrum disorder, developmental delay, and epilepsy. Taken together, our findings implicate de novo MCM6 variants in neurodevelopmental disorders. The clinical features and functional defects related to the zinc binding residue resemble those observed in syndromes related to other MCM components and DNA replication factors, while de novo OB-fold domain missense variants may be associated with more variable neurodevelopmental phenotypes. These data encourage consideration of MCM6 variants in the diagnostic arsenal of NDD.
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Affiliation(s)
- Daphne J Smits
- Department of Clinical Genetics, Erasmus University Medical Center, 3015 GD, Rotterdam, The Netherlands.
| | - Rachel Schot
- Department of Clinical Genetics, Erasmus University Medical Center, 3015 GD, Rotterdam, The Netherlands
- Discovery Unit, Department of Clinical Genetics, Erasmus University Medical Center, 3015 GD, Rotterdam, The Netherlands
| | - Cristiana A Popescu
- Department of Clinical Genetics, Erasmus University Medical Center, 3015 GD, Rotterdam, The Netherlands
| | - Kerith-Rae Dias
- Neuroscience Research Australia (NeuRA), University of New South Wales, Sydney, Australia
| | - Lesley Ades
- Department of Clinical Genetics, The Children's Hospital at Westmead, Westmead, NSW, Australia
- Specialty of Genomic Medicine, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia
| | - Lauren C Briere
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA
| | - David A Sweetser
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA
| | - Itaru Kushima
- Medical Genomics Center, Nagoya University Graduate School of Medicine, Nagoya, Japan
- Department of Psychiatry, Graduate School of Medicine, Nagoya University, Nagoya, Japan
| | - Branko Aleksic
- Department of Psychiatry, Graduate School of Medicine, Nagoya University, Nagoya, Japan
| | | | | | | | - Frank J G T Sleutels
- Department of Clinical Genetics, Erasmus University Medical Center, 3015 GD, Rotterdam, The Netherlands
| | - Daniëlle C M van der Kaay
- Department of Pediatrics, Subdivision of Endocrinology, Erasmus University Medical Center, Rotterdam, The Netherlands
| | | | - Hilde Van Esch
- Center for Human Genetics, University Hospitals Leuven, 3000, Leuven, Belgium
| | | | - Tony Roscioli
- Neuroscience Research Australia (NeuRA), University of New South Wales, Sydney, Australia
- New South Wales Health Pathology Randwick Genomics, Prince of Wales Hospital, Sydney, Australia
| | - Grazia M S Mancini
- Department of Clinical Genetics, Erasmus University Medical Center, 3015 GD, Rotterdam, The Netherlands
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13
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Zhang X, Zhou Z, Dai L, Chao Y, Liu Z, Huang M, Qu Q, Lin Z. Cryo-EM structure of the RuvAB-Holliday junction intermediate complex from Pseudomonas aeruginosa. FRONTIERS IN PLANT SCIENCE 2023; 14:1139106. [PMID: 37025142 PMCID: PMC10071043 DOI: 10.3389/fpls.2023.1139106] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Accepted: 02/27/2023] [Indexed: 06/19/2023]
Abstract
Holliday junction (HJ) is a four-way structured DNA intermediate in homologous recombination. In bacteria, the HJ-specific binding protein RuvA and the motor protein RuvB together form the RuvAB complex to catalyze HJ branch migration. Pseudomonas aeruginosa (P. aeruginosa, Pa) is a ubiquitous opportunistic bacterial pathogen that can cause serious infection in a variety of host species, including vertebrate animals, insects and plants. Here, we describe the cryo-Electron Microscopy (cryo-EM) structure of the RuvAB-HJ intermediate complex from P. aeruginosa. The structure shows that two RuvA tetramers sandwich HJ at the junction center and disrupt base pairs at the branch points of RuvB-free HJ arms. Eight RuvB subunits are recruited by the RuvA octameric core and form two open-rings to encircle two opposite HJ arms. Each RuvB subunit individually binds a RuvA domain III. The four RuvB subunits within the ring display distinct subdomain conformations, and two of them engage the central DNA duplex at both strands with their C-terminal β-hairpins. Together with the biochemical analyses, our structure implicates a potential mechanism of RuvB motor assembly onto HJ DNA.
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Affiliation(s)
- Xu Zhang
- College of Chemistry, Fuzhou University, Fuzhou, China
| | - Zixuan Zhou
- Shanghai Stomatological Hospital, Institutes of Biomedical Science, Department of Systems Biology for Medicine, Fudan University, Shanghai, China
| | - Lin Dai
- College of Chemistry, Fuzhou University, Fuzhou, China
| | - Yulin Chao
- Shanghai Stomatological Hospital, Institutes of Biomedical Science, Department of Systems Biology for Medicine, Fudan University, Shanghai, China
| | - Zheng Liu
- Kobilka Institute of Innovative Drug Discovery, School of Medicine, Chinese University of Hong Kong, Shenzhen, China
| | | | - Qianhui Qu
- Shanghai Stomatological Hospital, Institutes of Biomedical Science, Department of Systems Biology for Medicine, Fudan University, Shanghai, China
| | - Zhonghui Lin
- College of Chemistry, Fuzhou University, Fuzhou, China
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14
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Herrera LR, McGlynn K, Gibbs ZA, Davis AJ, Whitehurst AW. The Cancer Testes Antigen, HORMAD1, is a Tumor-Specific Replication Fork Protection Factor. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.31.526348. [PMID: 36778501 PMCID: PMC9915569 DOI: 10.1101/2023.01.31.526348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Tumors frequently activate the expression of genes that are only otherwise required for meiosis. HORMAD1, which is essential for meiotic recombination in multiple species, is expressed in over 50% of human lung adenocarcinoma cells (LUAD). We previously found that HORMAD1 promotes DNA double strand break (DSB) repair in LUAD. Here, we report that HORMAD1 takes on an additional role in protecting genomic integrity. Specifically, we find HORMAD1 is critical for protecting stalled DNA replication forks in LUAD. Loss of HORMAD1 leads to nascent DNA degradation, an event which is mediated by the MRE11-DNA2-BLM pathway. Moreover, following exogenous induction of DNA replication stress, HORMAD1 deleted cells accumulate single stranded DNA (ssDNA). We find that these phenotypes are the result of a lack of RAD51 and BRCA2 loading onto stalled replication forks. Ultimately, loss of HORMAD1 leads to increased DSBs and chromosomal aberrations in response to replication stress. Collectively, our data support a model where HORMAD1 expression is selected to mitigate DNA replication stress, which would otherwise induce deleterious genomic instability.
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15
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Song HY, Shen R, Mahasin H, Guo YN, Wang DG. DNA replication: Mechanisms and therapeutic interventions for diseases. MedComm (Beijing) 2023; 4:e210. [PMID: 36776764 PMCID: PMC9899494 DOI: 10.1002/mco2.210] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 01/08/2023] [Accepted: 01/09/2023] [Indexed: 02/09/2023] Open
Abstract
Accurate and integral cellular DNA replication is modulated by multiple replication-associated proteins, which is fundamental to preserve genome stability. Furthermore, replication proteins cooperate with multiple DNA damage factors to deal with replication stress through mechanisms beyond their role in replication. Cancer cells with chronic replication stress exhibit aberrant DNA replication and DNA damage response, providing an exploitable therapeutic target in tumors. Numerous evidence has indicated that posttranslational modifications (PTMs) of replication proteins present distinct functions in DNA replication and respond to replication stress. In addition, abundant replication proteins are involved in tumorigenesis and development, which act as diagnostic and prognostic biomarkers in some tumors, implying these proteins act as therapeutic targets in clinical. Replication-target cancer therapy emerges as the times require. In this context, we outline the current investigation of the DNA replication mechanism, and simultaneously enumerate the aberrant expression of replication proteins as hallmark for various diseases, revealing their therapeutic potential for target therapy. Meanwhile, we also discuss current observations that the novel PTM of replication proteins in response to replication stress, which seems to be a promising strategy to eliminate diseases.
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Affiliation(s)
- Hao-Yun Song
- School of Basic Medical Sciences Lanzhou University Lanzhou Gansu China
| | - Rong Shen
- School of Basic Medical Sciences Lanzhou University Lanzhou Gansu China
| | - Hamid Mahasin
- School of Basic Medical Sciences Lanzhou University Lanzhou Gansu China
| | - Ya-Nan Guo
- School of Basic Medical Sciences Lanzhou University Lanzhou Gansu China
| | - De-Gui Wang
- School of Basic Medical Sciences Lanzhou University Lanzhou Gansu China
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16
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Piccinini G, Milani L. Germline-related molecular phenotype in Metazoa: conservation and innovation highlighted by comparative transcriptomics. EvoDevo 2023; 14:2. [PMID: 36717890 PMCID: PMC9885605 DOI: 10.1186/s13227-022-00207-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 12/27/2022] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND In Metazoa, the germline represents the cell lineage devoted to the transmission of genetic heredity across generations. Its functions intuitively evoke the crucial roles that it plays in organism development and species evolution, and its establishment is tightly tied to animal multicellularity itself. The molecular toolkit expressed in germ cells has a high degree of conservation between species, and it also shares many components with the molecular phenotype of some animal totipotent cell lineages, like planarian neoblasts and sponge archaeocytes. The present study stems from these observations and represents a transcriptome-wide comparative analysis between germline-related samples of 9 animal species (7 phyla), comprehending also totipotent lineages classically considered somatic. RESULTS Differential expression analyses were performed for each species between germline-related and control somatic tissues. We then compared the different germline-related transcriptional profiles across the species without the need for an a priori set of genes. Through a phylostratigraphic analysis, we observed that the proportion of phylum- and Metazoa-specific genes among germline-related upregulated transcripts was lower than expected by chance for almost all species. Moreover, homologous genes related to proper DNA replication resulted the most common when comparing the considered species, while the regulation of transcription and post-transcriptional mechanisms appeared more variable, showing shared upregulated functions and domains, but very few homologous whole-length sequences. CONCLUSIONS Our wide-scale comparative analysis mostly confirmed previous molecular characterizations of specific germline-related lineages. Additionally, we observed a consistent signal throughout the whole data set, therefore comprehending both canonically defined germline samples (germ cells), and totipotent cell lineages classically considered somatic (neoblasts and archaeocytes). The phylostratigraphic analysis supported the less probable involvement of novel molecular factors in the germline-related transcriptional phenotype and highlighted the early origin of such cell programming and its conservation throughout evolution. Moreover, the fact that the mostly shared molecular factors were involved in DNA replication and repair suggests how fidelity in genetic material inheritance is a strong and conserved driver of germline-related molecular phenotype, while transcriptional and post-transcriptional regulations appear differently tuned among the lineages.
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Affiliation(s)
- Giovanni Piccinini
- grid.6292.f0000 0004 1757 1758Department of Biological, Geological, and Environmental Sciences, University of Bologna, Bologna, Italy
| | - Liliana Milani
- grid.6292.f0000 0004 1757 1758Department of Biological, Geological, and Environmental Sciences, University of Bologna, Bologna, Italy
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17
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The human pre-replication complex is an open complex. Cell 2023; 186:98-111.e21. [PMID: 36608662 DOI: 10.1016/j.cell.2022.12.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2022] [Revised: 10/13/2022] [Accepted: 12/05/2022] [Indexed: 01/07/2023]
Abstract
In eukaryotes, DNA replication initiation requires assembly and activation of the minichromosome maintenance (MCM) 2-7 double hexamer (DH) to melt origin DNA strands. However, the mechanism for this initial melting is unknown. Here, we report a 2.59-Å cryo-electron microscopy structure of the human MCM-DH (hMCM-DH), also known as the pre-replication complex. In this structure, the hMCM-DH with a constricted central channel untwists and stretches the DNA strands such that almost a half turn of the bound duplex DNA is distorted with 1 base pair completely separated, generating an initial open structure (IOS) at the hexamer junction. Disturbing the IOS inhibits DH formation and replication initiation. Mapping of hMCM-DH footprints indicates that IOSs are distributed across the genome in large clusters aligning well with initiation zones designed for stochastic origin firing. This work unravels an intrinsic mechanism that couples DH formation with initial DNA melting to license replication initiation in human cells.
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18
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SV40 T-antigen uses a DNA shearing mechanism to initiate origin unwinding. Proc Natl Acad Sci U S A 2022; 119:e2216240119. [PMID: 36442086 PMCID: PMC9894130 DOI: 10.1073/pnas.2216240119] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Duplication of DNA genomes requires unwinding of the double-strand (ds) DNA so that each single strand (ss) can be copied by a DNA polymerase. The genomes of eukaryotic cells are unwound by two ring-shaped hexameric helicases that initially encircle dsDNA but transition to ssDNA for function as replicative helicases. How the duplex is initially unwound, and the role of the two helicases in this process, is poorly understood. We recently described an initiation mechanism for eukaryotes in which the two helicases are directed inward toward one another and shear the duplex open by pulling on opposite strands of the duplex while encircling dsDNA [L. D. Langston, M. E. O'Donnell, eLife 8, e46515 (2019)]. Two head-to-head T-Antigen helicases are long known to be loaded at the SV40 origin. We show here that T-Antigen tracks head (N-tier) first on ssDNA, opposite the direction proposed for decades. We also find that SV40 T-Antigen tracks directionally while encircling dsDNA and mainly tracks on one strand of the duplex in the same orientation as during ssDNA translocation. Further, two inward directed T-Antigen helicases on dsDNA are able to melt a 150-bp duplex. These findings explain the "rabbit ear" DNA loops observed at the SV40 origin by electron microscopy and reconfigure how the DNA loops emerge from the double hexamer relative to earlier models. Thus, the mechanism of DNA shearing by two opposing helicases is conserved in a eukaryotic viral helicase and may be widely used to initiate origin unwinding of dsDNA genomes.
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19
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Two Distinct Modes of DNA Binding by an MCM Helicase Enable DNA Translocation. Int J Mol Sci 2022; 23:ijms232314678. [PMID: 36499022 PMCID: PMC9735655 DOI: 10.3390/ijms232314678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 11/11/2022] [Accepted: 11/16/2022] [Indexed: 11/26/2022] Open
Abstract
A six-subunit ATPase ring forms the central hub of the replication forks in all domains of life. This ring performs a helicase function to separate the two complementary DNA strands to be replicated and drives the replication machinery along the DNA. Disruption of this helicase/ATPase ring is associated with genetic instability and diseases such as cancer. The helicase/ATPase rings of eukaryotes and archaea consist of six minichromosome maintenance (MCM) proteins. Prior structural studies have shown that MCM rings bind one encircled strand of DNA in a spiral staircase, suggesting that the ring pulls this strand of DNA through its central pore in a hand-over-hand mechanism where the subunit at the bottom of the staircase dissociates from DNA and re-binds DNA one step above the staircase. With high-resolution cryo-EM, we show that the MCM ring of the archaeal organism Saccharolobus solfataricus binds an encircled DNA strand in two different modes with different numbers of subunits engaged to DNA, illustrating a plausible mechanism for the alternating steps of DNA dissociation and re-association that occur during DNA translocation.
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20
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Yeager C, Carter G, Gohara DW, Yennawar NH, Enemark E, Arnold J, Cameron CE. Enteroviral 2C protein is an RNA-stimulated ATPase and uses a two-step mechanism for binding to RNA and ATP. Nucleic Acids Res 2022; 50:11775-11798. [PMID: 36399514 PMCID: PMC9723501 DOI: 10.1093/nar/gkac1054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 10/16/2022] [Accepted: 10/26/2022] [Indexed: 11/19/2022] Open
Abstract
The enteroviral 2C protein is a therapeutic target, but the absence of a mechanistic framework for this enzyme limits our understanding of inhibitor mechanisms. Here, we use poliovirus 2C and a derivative thereof to elucidate the first biochemical mechanism for this enzyme and confirm the applicability of this mechanism to other members of the enterovirus genus. Our biochemical data are consistent with a dimer forming in solution, binding to RNA, which stimulates ATPase activity by increasing the rate of hydrolysis without impacting affinity for ATP substantially. Both RNA and DNA bind to the same or overlapping site on 2C, driven by the phosphodiester backbone, but only RNA stimulates ATP hydrolysis. We propose that RNA binds to 2C driven by the backbone, with reorientation of the ribose hydroxyls occurring in a second step to form the catalytically competent state. 2C also uses a two-step mechanism for binding to ATP. Initial binding is driven by the α and β phosphates of ATP. In the second step, the adenine base and other substituents of ATP are used to organize the active site for catalysis. These studies provide the first biochemical description of determinants driving specificity and catalytic efficiency of a picornaviral 2C ATPase.
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Affiliation(s)
- Calvin Yeager
- Department of Microbiology & Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Griffin Carter
- Department of Microbiology & Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - David W Gohara
- Department of Biochemistry and Molecular Biology, St. Louis University, St. Louis, MO 63104, USA
| | - Neela H Yennawar
- The Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA 16802, USA
| | - Eric J Enemark
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Jamie J Arnold
- Department of Microbiology & Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Craig E Cameron
- To whom correspondence should be addressed. Tel: +1 919 966 9699; Fax: +1 919 962 8103;
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21
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Li Z, Kaur P, Lo CY, Chopra N, Smith J, Wang H, Gao Y. Structural and dynamic basis of DNA capture and translocation by mitochondrial Twinkle helicase. Nucleic Acids Res 2022; 50:11965-11978. [PMID: 36400570 PMCID: PMC9723800 DOI: 10.1093/nar/gkac1089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2022] [Revised: 10/21/2022] [Accepted: 10/26/2022] [Indexed: 11/21/2022] Open
Abstract
Twinkle is a mitochondrial replicative helicase which can self-load onto and unwind mitochondrial DNA. Nearly 60 mutations on Twinkle have been linked to human mitochondrial diseases. Using cryo-electron microscopy (cryo-EM) and high-speed atomic force microscopy (HS-AFM), we obtained the atomic-resolution structure of a vertebrate Twinkle homolog with DNA and captured in real-time how Twinkle is self-loaded onto DNA. Our data highlight the important role of the non-catalytic N-terminal domain of Twinkle. The N-terminal domain directly contacts the C-terminal helicase domain, and the contact interface is a hotspot for disease-related mutations. Mutations at the interface destabilize Twinkle hexamer and reduce helicase activity. With HS-AFM, we observed that a highly dynamic Twinkle domain, which is likely to be the N-terminal domain, can protrude ∼5 nm to transiently capture nearby DNA and initialize Twinkle loading onto DNA. Moreover, structural analysis and subunit doping experiments suggest that Twinkle hydrolyzes ATP stochastically, which is distinct from related helicases from bacteriophages.
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Affiliation(s)
- Zhuo Li
- BioSciences Department, Rice University, Houston, TX 77005, USA
| | - Parminder Kaur
- Physics Department, North Carolina State University, Raleigh, NC 27695, USA
- Center for Human Health and the Environment, North Carolina State University, Raleigh, NC 27695, USA
| | - Chen-Yu Lo
- BioSciences Department, Rice University, Houston, TX 77005, USA
| | - Neil Chopra
- BioSciences Department, Rice University, Houston, TX 77005, USA
| | - Jamie Smith
- BioSciences Department, Rice University, Houston, TX 77005, USA
| | - Hong Wang
- Physics Department, North Carolina State University, Raleigh, NC 27695, USA
- Center for Human Health and the Environment, North Carolina State University, Raleigh, NC 27695, USA
- Toxicology Program, North Carolina State University, Raleigh, NC 27695, USA
| | - Yang Gao
- BioSciences Department, Rice University, Houston, TX 77005, USA
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22
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Popov AL, Zholobak NM, Shcherbakov AB, Kozlova TO, Kolmanovich DD, Ermakov AM, Popova NR, Chukavin NN, Bazikyan EA, Ivanov VK. The Strong Protective Action of Ce 3+/F - Combined Treatment on Tooth Enamel and Epithelial Cells. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:3034. [PMID: 36080071 PMCID: PMC9457955 DOI: 10.3390/nano12173034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 08/14/2022] [Accepted: 08/28/2022] [Indexed: 06/15/2023]
Abstract
We studied the toxic effects of cerium and fluoride species on human dental pulp stem cells and epithelial cells of Cercopithecus aethiops as a surrogate for the human oral mucosa. The sequential use of CeCl3 and NH4F solutions in equimolar sub-toxic concentrations enabled the possible toxic effects of individual components to be avoided, ensuring the preservation of the metabolic activity of the cells due to the formation of CeF3 nanoparticles. Cerium fluoride nanoparticles and terbium-doped cerium fluoride nanoparticles exhibited neither cytotoxicity nor genotoxicity to dental pulp stem cells, even at high concentrations (10-4 M). In millimolar concentrations (from 10-5-10-6 M), these nanoparticles significantly increased the expression of genes responsible for the cell cycle, differentiation and proliferation. The formation of cerium fluoride on the surface of the mucous membrane and teeth provided protection against the development of carious lesions, periodontitis, ROS attacks and other inflammatory diseases of the oral cavity. Luminescent CeF3: Tb nanoparticles enabled the visualization of tooth enamel microcracks.
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Affiliation(s)
- Anton L. Popov
- Kurnakov Institute of General and Inorganic Chemistry of the Russian Academy of Sciences, Moscow 119991, Russia
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino 142290, Moscow Region, Russia
| | - Nadia M. Zholobak
- Zabolotny Institute of Microbiology and Virology, National Academy of Sciences of Ukraine, Kyiv 03680, Ukraine
| | - Alexander B. Shcherbakov
- Zabolotny Institute of Microbiology and Virology, National Academy of Sciences of Ukraine, Kyiv 03680, Ukraine
| | - Taisiya O. Kozlova
- Kurnakov Institute of General and Inorganic Chemistry of the Russian Academy of Sciences, Moscow 119991, Russia
| | - Danil D. Kolmanovich
- Kurnakov Institute of General and Inorganic Chemistry of the Russian Academy of Sciences, Moscow 119991, Russia
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino 142290, Moscow Region, Russia
| | - Artem M. Ermakov
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino 142290, Moscow Region, Russia
- Moscow Region State University, Moscow 141014, Russia
| | - Nelli R. Popova
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino 142290, Moscow Region, Russia
| | - Nikita N. Chukavin
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino 142290, Moscow Region, Russia
- Moscow Region State University, Moscow 141014, Russia
| | - Ernest A. Bazikyan
- Yevdokimov Moscow State University of Medicine and Dentistry, Moscow 127473, Russia
| | - Vladimir K. Ivanov
- Kurnakov Institute of General and Inorganic Chemistry of the Russian Academy of Sciences, Moscow 119991, Russia
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23
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Shaw AE, Kairamkonda S, Ghodke H, Schauer GD. Biochemical and single-molecule techniques to study accessory helicase resolution of R-loop proteins at stalled replication forks. Methods Enzymol 2022; 673:191-225. [PMID: 35965008 DOI: 10.1016/bs.mie.2022.03.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
R-loop proteins present a stable and robust blockade to the progression of a DNA replication fork during S-phase. The consequences of this block can include mutagenesis and other irreversible chromosomal catastrophes, causing genomic instability and disease. As such, further investigation into the molecular mechanisms underlying R-loop protein resolution is warranted. The critical role of non-replicative accessory helicases in R-loop protein resolution has increasingly come into light in recent years. Such helicases include the Pif1-family, monomeric helicases that have been studied in many different contexts and that have been ascribed to a multitude of separable protective functions in the cell. In this chapter, we present protocols to study R-loop protein resolution by Pif1 helicase at stalled replication forks using purified proteins, both at the biochemical and single-molecule level. Our system uses recombinant proteins expressed in Saccharomyces cerevisiae but could apply to practically any organism of interest due to the high interspecies homology of the proteins involved in DNA replication. The methods we outline are extensible to many systems and should be applicable to studying R-loop clearance by any Superfamily (SF) 1B helicase. These techniques will further enable mechanistic research on these critical but understudied components of the genomic maintenance program.
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Affiliation(s)
- Alisa E Shaw
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, United States
| | - Sreeya Kairamkonda
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, United States
| | - Harshad Ghodke
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia; Illawarra Health & Medical Research Institute, Wollongong, NSW, Australia
| | - Grant D Schauer
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, United States.
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24
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Jin S, Bueno C, Lu W, Wang Q, Chen M, Chen X, Wolynes PG, Gao Y. Computationally exploring the mechanism of bacteriophage T7 gp4 helicase translocating along ssDNA. Proc Natl Acad Sci U S A 2022; 119:e2202239119. [PMID: 35914145 PMCID: PMC9371691 DOI: 10.1073/pnas.2202239119] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 07/05/2022] [Indexed: 12/12/2022] Open
Abstract
Bacteriophage T7 gp4 helicase has served as a model system for understanding mechanisms of hexameric replicative helicase translocation. The mechanistic basis of how nucleoside 5'-triphosphate hydrolysis and translocation of gp4 helicase are coupled is not fully resolved. Here, we used a thermodynamically benchmarked coarse-grained protein force field, Associative memory, Water mediated, Structure and Energy Model (AWSEM), with the single-stranded DNA (ssDNA) force field 3SPN.2C to investigate gp4 translocation. We found that the adenosine 5'-triphosphate (ATP) at the subunit interface stabilizes the subunit-subunit interaction and inhibits subunit translocation. Hydrolysis of ATP to adenosine 5'-diphosphate enables the translocation of one subunit, and new ATP binding at the new subunit interface finalizes the subunit translocation. The LoopD2 and the N-terminal primase domain provide transient protein-protein and protein-DNA interactions that facilitate the large-scale subunit movement. The simulations of gp4 helicase both validate our coarse-grained protein-ssDNA force field and elucidate the molecular basis of replicative helicase translocation.
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Affiliation(s)
- Shikai Jin
- Department of Biosciences, Rice University, Houston, TX 77005
- Center for Theoretical Biological Physics, Rice University, Houston, TX 77005
| | - Carlos Bueno
- Center for Theoretical Biological Physics, Rice University, Houston, TX 77005
| | - Wei Lu
- Center for Theoretical Biological Physics, Rice University, Houston, TX 77005
- Department of Physics, Rice University, Houston, TX 77005
| | - Qian Wang
- Department of Physics, University of Science and Technology of China, Hefei 230026, China
| | - Mingchen Chen
- Department of Research and Development, neoX Biotech, Beijing 100206, China
| | - Xun Chen
- Center for Theoretical Biological Physics, Rice University, Houston, TX 77005
- Department of Chemistry, Rice University, Houston, TX 77005
| | - Peter G Wolynes
- Department of Biosciences, Rice University, Houston, TX 77005
- Center for Theoretical Biological Physics, Rice University, Houston, TX 77005
- Department of Physics, Rice University, Houston, TX 77005
- Department of Chemistry, Rice University, Houston, TX 77005
| | - Yang Gao
- Department of Biosciences, Rice University, Houston, TX 77005
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25
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Qiao C, Debiasi-Anders G, Mir-Sanchis I. Staphylococcal self-loading helicases couple the staircase mechanism with inter domain high flexibility. Nucleic Acids Res 2022; 50:8349-8362. [PMID: 35871290 PMCID: PMC9371898 DOI: 10.1093/nar/gkac625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 06/24/2022] [Accepted: 07/20/2022] [Indexed: 11/13/2022] Open
Abstract
Abstract
Replication is a crucial cellular process. Replicative helicases unwind DNA providing the template strand to the polymerase and promoting replication fork progression. Helicases are multi-domain proteins which use an ATPase domain to couple ATP hydrolysis with translocation, however the role that the other domains might have during translocation remains elusive. Here, we studied the unexplored self-loading helicases called Reps, present in Staphylococcus aureus pathogenicity islands (SaPIs). Our cryoEM structures of the PriRep5 from SaPI5 (3.3 Å), the Rep1 from SaPI1 (3.9 Å) and Rep1–DNA complex (3.1Å) showed that in both Reps, the C-terminal domain (CTD) undergoes two distinct movements respect the ATPase domain. We experimentally demonstrate both in vitro and in vivo that SaPI-encoded Reps need key amino acids involved in the staircase mechanism of translocation. Additionally, we demonstrate that the CTD′s presence is necessary for the maintenance of full ATPase and helicase activities. We speculate that this high interdomain flexibility couples Rep′s activities as initiators and as helicases.
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Affiliation(s)
- Cuncun Qiao
- Department of Medical Biochemistry and Biophysics, Umeå University , Umeå , Sweden
- Wallenberg Centre for Molecular Medicine , Umeå , Sweden
| | - Gianluca Debiasi-Anders
- Department of Medical Biochemistry and Biophysics, Umeå University , Umeå , Sweden
- Wallenberg Centre for Molecular Medicine , Umeå , Sweden
| | - Ignacio Mir-Sanchis
- Department of Medical Biochemistry and Biophysics, Umeå University , Umeå , Sweden
- Wallenberg Centre for Molecular Medicine , Umeå , Sweden
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26
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Na Z, Dai X, Zheng SJ, Bryant CJ, Loh KH, Su H, Luo Y, Buhagiar AF, Cao X, Baserga SJ, Chen S, Slavoff SA. Mapping subcellular localizations of unannotated microproteins and alternative proteins with MicroID. Mol Cell 2022; 82:2900-2911.e7. [PMID: 35905735 PMCID: PMC9662605 DOI: 10.1016/j.molcel.2022.06.035] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 04/08/2022] [Accepted: 06/29/2022] [Indexed: 11/15/2022]
Abstract
Proteogenomic identification of translated small open reading frames has revealed thousands of previously unannotated, largely uncharacterized microproteins, or polypeptides of less than 100 amino acids, and alternative proteins (alt-proteins) that are co-encoded with canonical proteins and are often larger. The subcellular localizations of microproteins and alt-proteins are generally unknown but can have significant implications for their functions. Proximity biotinylation is an attractive approach to define the protein composition of subcellular compartments in cells and in animals. Here, we developed a high-throughput technology to map unannotated microproteins and alt-proteins to subcellular localizations by proximity biotinylation with TurboID (MicroID). More than 150 microproteins and alt-proteins are associated with subnuclear organelles. One alt-protein, alt-LAMA3, localizes to the nucleolus and functions in pre-rRNA transcription. We applied MicroID in a mouse model, validating expression of a conserved nuclear microprotein, and establishing MicroID for discovery of microproteins and alt-proteins in vivo.
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Affiliation(s)
- Zhenkun Na
- Department of Chemistry, Yale University, New Haven, CT 06520, USA; Institute of Biomolecular Design and Discovery, Yale University, West Haven, CT 06516, USA
| | - Xiaoyun Dai
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06520, USA; Systems Biology Institute, Yale University, West Haven, CT 06516, USA
| | - Shu-Jian Zheng
- Department of Chemistry, Yale University, New Haven, CT 06520, USA; Institute of Biomolecular Design and Discovery, Yale University, West Haven, CT 06516, USA
| | - Carson J Bryant
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06529, USA
| | - Ken H Loh
- Laboratory of Molecular Genetics, Howard Hughes Medical Institute, The Rockefeller University, New York, NY 10065, USA
| | - Haomiao Su
- Department of Chemistry, Yale University, New Haven, CT 06520, USA; Institute of Biomolecular Design and Discovery, Yale University, West Haven, CT 06516, USA
| | - Yang Luo
- Department of Chemistry, Yale University, New Haven, CT 06520, USA; Institute of Biomolecular Design and Discovery, Yale University, West Haven, CT 06516, USA
| | - Amber F Buhagiar
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06529, USA
| | - Xiongwen Cao
- Department of Chemistry, Yale University, New Haven, CT 06520, USA; Institute of Biomolecular Design and Discovery, Yale University, West Haven, CT 06516, USA
| | - Susan J Baserga
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06529, USA; Department of Genetics, Yale University School of Medicine, New Haven, CT 06520, USA; Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Sidi Chen
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06520, USA; Systems Biology Institute, Yale University, West Haven, CT 06516, USA
| | - Sarah A Slavoff
- Department of Chemistry, Yale University, New Haven, CT 06520, USA; Institute of Biomolecular Design and Discovery, Yale University, West Haven, CT 06516, USA; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06529, USA.
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27
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Li L, Xia T, Li B, Yang H. Hormone and carbohydrate metabolism associated genes play important roles in rhizome bud full-year germination of Cephalostachyum pingbianense. PHYSIOLOGIA PLANTARUM 2022; 174:e13674. [PMID: 35306669 DOI: 10.1111/ppl.13674] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 03/06/2022] [Accepted: 03/14/2022] [Indexed: 06/14/2023]
Abstract
Cephalostachyum pingbianense is the only woody bamboo species that can produce bamboo shoots in four seasons under natural conditions. So far, the regulatory mechanism of shoot bud differentiation and development is unknown. In the present study, indole-3-acetic acid (IAA), zeatin riboside (ZR), gibberellin A3 (GA3 ) and abscisic acid (ABA) contents determination, RNA sequencing and differentially expressed gene analysis were performed on dormant rhizome bud (DR), growing rhizome bud (GR), and germinative bud (GB) in each season. The results showed that the contents of IAA and ZR increased while ABA content decreased, and GA3 content was stable during bud transition from dormancy to germination in each season. Moreover, rhizome bud germination was cooperatively regulated by multiple pathways such as carbohydrate metabolism, hormone signal transduction, cell wall biogenesis, temperature response, and water transport. The inferred hub genes among these candidates were identified by protein-protein interaction network analyses, most of which were involved in hormone and carbohydrate metabolism, such as HK and BGLU4 in spring, IDH and GH3 in winter, GPI and talA/talB in summer and autumn. It is speculated that dynamic phytohormone changes and differential expression of these genes promote the release of rhizome bud dormancy and contribute to the phenological characteristics of full-year shooting. Moreover, the rhizome buds of C. pingbianense may not suffer from ecodormancy in winter. These findings would help accumulate knowledge on shooting mechanisms in woody bamboos and provide a physiological insight into germplasm conservation and forest management of C. pingbianense.
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Affiliation(s)
- Lushuang Li
- Institute of Highland Forest Science, Chinese Academy of Forestry, Kunming, Yunnan, China
| | - Tize Xia
- Institute of Highland Forest Science, Chinese Academy of Forestry, Kunming, Yunnan, China
| | - Bin Li
- Institute of Highland Forest Science, Chinese Academy of Forestry, Kunming, Yunnan, China
| | - Hanqi Yang
- Institute of Highland Forest Science, Chinese Academy of Forestry, Kunming, Yunnan, China
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28
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Abstract
DNA replication in eukaryotic cells initiates from large numbers of sites called replication origins. Initiation of replication from these origins must be tightly controlled to ensure the entire genome is precisely duplicated in each cell cycle. This is accomplished through the regulation of the first two steps in replication: loading and activation of the replicative DNA helicase. Here we describe what is known about the mechanism and regulation of these two reactions from a genetic, biochemical, and structural perspective, focusing on recent progress using proteins from budding yeast. Expected final online publication date for the Annual Review of Biochemistry, Volume 91 is June 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Alessandro Costa
- Macromolecular Machines Laboratory, The Francis Crick Institute, London, UK;
| | - John F X Diffley
- Chromosome Replication Laboratory, The Francis Crick Institute, London, UK;
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29
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Yeast Stn1 promotes MCM to circumvent Rad53 control of the S phase checkpoint. Curr Genet 2022; 68:165-179. [PMID: 35150303 PMCID: PMC8976814 DOI: 10.1007/s00294-022-01228-0] [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: 07/13/2021] [Revised: 12/06/2021] [Accepted: 12/16/2021] [Indexed: 11/17/2022]
Abstract
Treating yeast cells with the replication inhibitor hydroxyurea activates the S phase checkpoint kinase Rad53, eliciting responses that block DNA replication origin firing, stabilize replication forks, and prevent premature extension of the mitotic spindle. We previously found overproduction of Stn1, a subunit of the telomere-binding Cdc13–Stn1–Ten1 complex, circumvents Rad53 checkpoint functions in hydroxyurea, inducing late origin firing and premature spindle extension even though Rad53 is activated normally. Here, we show Stn1 overproduction acts through remarkably similar pathways compared to loss of RAD53, converging on the MCM complex that initiates origin firing and forms the catalytic core of the replicative DNA helicase. First, mutations affecting Mcm2 and Mcm5 block the ability of Stn1 overproduction to disrupt the S phase checkpoint. Second, loss of function stn1 mutations compensate rad53 S phase checkpoint defects. Third Stn1 overproduction suppresses a mutation in Mcm7. Fourth, stn1 mutants accumulate single-stranded DNA at non-telomeric genome locations, imposing a requirement for post-replication DNA repair. We discuss these interactions in terms of a model in which Stn1 acts as an accessory replication factor that facilitates MCM activation at ORIs and potentially also maintains MCM activity at replication forks advancing through challenging templates.
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30
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Bianco PR. OB-fold Families of Genome Guardians: A Universal Theme Constructed From the Small β-barrel Building Block. Front Mol Biosci 2022; 9:784451. [PMID: 35223988 PMCID: PMC8881015 DOI: 10.3389/fmolb.2022.784451] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 01/19/2022] [Indexed: 11/13/2022] Open
Abstract
The maintenance of genome stability requires the coordinated actions of multiple proteins and protein complexes, that are collectively known as genome guardians. Within this broadly defined family is a subset of proteins that contain oligonucleotide/oligosaccharide-binding folds (OB-fold). While OB-folds are widely associated with binding to single-stranded DNA this view is no longer an accurate depiction of how these domains are utilized. Instead, the core of the OB-fold is modified and adapted to facilitate binding to a variety of DNA substrates (both single- and double-stranded), phospholipids, and proteins, as well as enabling catalytic function to a multi-subunit complex. The flexibility accompanied by distinctive oligomerization states and quaternary structures enables OB-fold genome guardians to maintain the integrity of the genome via a myriad of complex and dynamic, protein-protein; protein-DNA, and protein-lipid interactions in both prokaryotes and eukaryotes.
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Affiliation(s)
- Piero R. Bianco
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, NE, United States
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31
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Multiple roles of Pol epsilon in eukaryotic chromosome replication. Biochem Soc Trans 2022; 50:309-320. [PMID: 35129614 PMCID: PMC9022971 DOI: 10.1042/bst20210082] [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: 10/15/2021] [Revised: 12/23/2021] [Accepted: 01/06/2022] [Indexed: 11/17/2022]
Abstract
Pol epsilon is a tetrameric assembly that plays distinct roles during eukaryotic chromosome replication. It catalyses leading strand DNA synthesis; yet this function is dispensable for viability. Its non-catalytic domains instead play an essential role in the assembly of the active replicative helicase and origin activation, while non-essential histone-fold subunits serve a critical function in parental histone redeposition onto newly synthesised DNA. Furthermore, Pol epsilon plays a structural role in linking the RFC–Ctf18 clamp loader to the replisome, supporting processive DNA synthesis, DNA damage response signalling as well as sister chromatid cohesion. In this minireview, we discuss recent biochemical and structural work that begins to explain various aspects of eukaryotic chromosome replication, with a focus on the multiple roles of Pol epsilon in this process.
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32
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Abstract
Ring-shaped hexameric helicases are essential motor proteins that separate duplex nucleic acid strands for DNA replication, recombination, and transcriptional regulation. Two evolutionarily distinct lineages of these enzymes, predicated on RecA and AAA+ ATPase folds, have been identified and characterized to date. Hexameric helicases couple NTP hydrolysis with conformational changes that move nucleic acid substrates through a central pore in the enzyme. How hexameric helicases productively engage client DNA or RNA segments and use successive rounds of NTPase activity to power translocation and unwinding have been longstanding questions in the field. Recent structural and biophysical findings are beginning to reveal commonalities in NTP hydrolysis and substrate translocation by diverse hexameric helicase families. Here, we review these molecular mechanisms and highlight aspects of their function that are yet to be understood.
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33
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Determining translocation orientations of nucleic acid helicases. Methods 2021; 204:160-171. [PMID: 34758393 PMCID: PMC9076756 DOI: 10.1016/j.ymeth.2021.11.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 10/29/2021] [Accepted: 11/02/2021] [Indexed: 11/20/2022] Open
Abstract
Helicase enzymes translocate along an RNA or DNA template with a defined polarity to unwind, separate, or remodel duplex strands for a variety of genome maintenance processes. Helicase mutations are commonly associated with a variety of diseases including aging, cancer, and neurodegeneration. Biochemical characterization of these enzymes has provided a wealth of information on the kinetics of unwinding and substrate preferences, and several high-resolution structures of helicases alone and bound to oligonucleotides have been solved. Together, they provide mechanistic insights into the structural translocation and unwinding orientations of helicases. However, these insights rely on structural inferences derived from static snapshots. Instead, continued efforts should be made to combine structure and kinetics to better define active translocation orientations of helicases. This review explores many of the biochemical and biophysical methods utilized to map helicase binding orientation to DNA or RNA substrates and includes several time-dependent methods to unequivocally map the active translocation orientation of these enzymes to better define the active leading and trailing faces.
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34
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Khan YA, White KI, Brunger AT. The AAA+ superfamily: a review of the structural and mechanistic principles of these molecular machines. Crit Rev Biochem Mol Biol 2021; 57:156-187. [PMID: 34632886 DOI: 10.1080/10409238.2021.1979460] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
ATPases associated with diverse cellular activities (AAA+ proteins) are a superfamily of proteins found throughout all domains of life. The hallmark of this family is a conserved AAA+ domain responsible for a diverse range of cellular activities. Typically, AAA+ proteins transduce chemical energy from the hydrolysis of ATP into mechanical energy through conformational change, which can drive a variety of biological processes. AAA+ proteins operate in a variety of cellular contexts with diverse functions including disassembly of SNARE proteins, protein quality control, DNA replication, ribosome assembly, and viral replication. This breadth of function illustrates both the importance of AAA+ proteins in health and disease and emphasizes the importance of understanding conserved mechanisms of chemo-mechanical energy transduction. This review is divided into three major portions. First, the core AAA+ fold is presented. Next, the seven different clades of AAA+ proteins and structural details and reclassification pertaining to proteins in each clade are described. Finally, two well-known AAA+ proteins, NSF and its close relative p97, are reviewed in detail.
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Affiliation(s)
- Yousuf A Khan
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA.,Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA.,Department of Structural Biology, Stanford University, Stanford, CA, USA.,Department of Photon Science, Stanford University, Stanford, CA, USA.,Center for Biomedical Informatics Research, Stanford University, Stanford, CA, USA
| | - K Ian White
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA.,Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA.,Department of Structural Biology, Stanford University, Stanford, CA, USA.,Department of Photon Science, Stanford University, Stanford, CA, USA.,Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA
| | - Axel T Brunger
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA.,Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA.,Department of Structural Biology, Stanford University, Stanford, CA, USA.,Department of Photon Science, Stanford University, Stanford, CA, USA.,Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA
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35
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Unwinding of a DNA replication fork by a hexameric viral helicase. Nat Commun 2021; 12:5535. [PMID: 34545080 PMCID: PMC8452682 DOI: 10.1038/s41467-021-25843-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 08/31/2021] [Indexed: 11/16/2022] Open
Abstract
Hexameric helicases are motor proteins that unwind double-stranded DNA (dsDNA) during DNA replication but how they are optimised for strand separation is unclear. Here we present the cryo-EM structure of the full-length E1 helicase from papillomavirus, revealing all arms of a bound DNA replication fork and their interactions with the helicase. The replication fork junction is located at the entrance to the helicase collar ring, that sits above the AAA + motor assembly. dsDNA is escorted to and the 5´ single-stranded DNA (ssDNA) away from the unwinding point by the E1 dsDNA origin binding domains. The 3´ ssDNA interacts with six spirally-arranged β-hairpins and their cyclical top-to-bottom movement pulls the ssDNA through the helicase. Pulling of the RF against the collar ring separates the base-pairs, while modelling of the conformational cycle suggest an accompanying movement of the collar ring has an auxiliary role, helping to make efficient use of ATP in duplex unwinding. Replicative hexameric helicases are fundamental components of replisomes. Here the authors resolve a cryo-EM structure of the E1 helicase from papillomavirus bound to a DNA replication fork, providing insights into the mechanism of DNA unwinding by these hexameric enzymes.
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36
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Lewis AM, Recalde A, Bräsen C, Counts JA, Nussbaum P, Bost J, Schocke L, Shen L, Willard DJ, Quax TEF, Peeters E, Siebers B, Albers SV, Kelly RM. The biology of thermoacidophilic archaea from the order Sulfolobales. FEMS Microbiol Rev 2021; 45:fuaa063. [PMID: 33476388 PMCID: PMC8557808 DOI: 10.1093/femsre/fuaa063] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 11/26/2020] [Indexed: 12/13/2022] Open
Abstract
Thermoacidophilic archaea belonging to the order Sulfolobales thrive in extreme biotopes, such as sulfuric hot springs and ore deposits. These microorganisms have been model systems for understanding life in extreme environments, as well as for probing the evolution of both molecular genetic processes and central metabolic pathways. Thermoacidophiles, such as the Sulfolobales, use typical microbial responses to persist in hot acid (e.g. motility, stress response, biofilm formation), albeit with some unusual twists. They also exhibit unique physiological features, including iron and sulfur chemolithoautotrophy, that differentiate them from much of the microbial world. Although first discovered >50 years ago, it was not until recently that genome sequence data and facile genetic tools have been developed for species in the Sulfolobales. These advances have not only opened up ways to further probe novel features of these microbes but also paved the way for their potential biotechnological applications. Discussed here are the nuances of the thermoacidophilic lifestyle of the Sulfolobales, including their evolutionary placement, cell biology, survival strategies, genetic tools, metabolic processes and physiological attributes together with how these characteristics make thermoacidophiles ideal platforms for specialized industrial processes.
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Affiliation(s)
- April M Lewis
- Department of Chemical and Biomolecular Engineering, North Carolina State University. Raleigh, NC 27695, USA
| | - Alejandra Recalde
- Institute for Biology, Molecular Biology of Archaea, University of Freiburg, 79104 Freiburg, Germany
| | - Christopher Bräsen
- Department of Molecular Enzyme Technology and Biochemistry, Environmental Microbiology and Biotechnology, and Centre for Water and Environmental Research, University of Duisburg-Essen, 45117 Essen, Germany
| | - James A Counts
- Department of Chemical and Biomolecular Engineering, North Carolina State University. Raleigh, NC 27695, USA
| | - Phillip Nussbaum
- Institute for Biology, Molecular Biology of Archaea, University of Freiburg, 79104 Freiburg, Germany
| | - Jan Bost
- Institute for Biology, Molecular Biology of Archaea, University of Freiburg, 79104 Freiburg, Germany
| | - Larissa Schocke
- Department of Molecular Enzyme Technology and Biochemistry, Environmental Microbiology and Biotechnology, and Centre for Water and Environmental Research, University of Duisburg-Essen, 45117 Essen, Germany
| | - Lu Shen
- Department of Molecular Enzyme Technology and Biochemistry, Environmental Microbiology and Biotechnology, and Centre for Water and Environmental Research, University of Duisburg-Essen, 45117 Essen, Germany
| | - Daniel J Willard
- Department of Chemical and Biomolecular Engineering, North Carolina State University. Raleigh, NC 27695, USA
| | - Tessa E F Quax
- Archaeal Virus–Host Interactions, Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Eveline Peeters
- Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, 1050 Brussels, Belgium
| | - Bettina Siebers
- Department of Molecular Enzyme Technology and Biochemistry, Environmental Microbiology and Biotechnology, and Centre for Water and Environmental Research, University of Duisburg-Essen, 45117 Essen, Germany
| | - Sonja-Verena Albers
- Institute for Biology, Molecular Biology of Archaea, University of Freiburg, 79104 Freiburg, Germany
| | - Robert M Kelly
- Department of Chemical and Biomolecular Engineering, North Carolina State University. Raleigh, NC 27695, USA
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Gu Y, Hu X, Liu X, Cheng C, Chen K, Wu Y, Wu Z. MCM6 indicates adverse tumor features and poor outcomes and promotes G1/S cell cycle progression in neuroblastoma. BMC Cancer 2021; 21:784. [PMID: 34233647 PMCID: PMC8262023 DOI: 10.1186/s12885-021-08344-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 05/11/2021] [Indexed: 11/10/2022] Open
Abstract
Background Minichromosome maintenance complex component 6 (MCM6), as an important replication permission factor, is involved in the pathogenesis of various tumors. Here we studied the expression of MCM6 in neuroblastoma and its influence on tumor characteristics and prognosis. Methods Publicly available datasets were used to explore the influence of the differential expression of MCM6 on neuroblastoma tumor stage, risk and prognosis. In cell experiments, human neuroblastoma cell lines SK-N-SH and SK-N-BE [ (2)] were utilized to verify the ability of MCM6 to promote cell proliferation, migration and invasion. We further explored the possible molecular mechanism of MCM6 affecting the phenotype of neuroblastoma cells by mutual verification of RNA-seq and western blotting, and flow cytometry to inquire about its potential specific roles in the cell cycle. Results Through multiple datasets mining, we found that high expression of MCM6 was positively correlated with elevated tumor stage, high risk and poor prognosis in neuroblastoma. At the cellular level, neuroblastoma cell proliferation, migration and invasion were significantly inhibited after MCM6 was interfered by siRNA. Mutual verification of RNA-seq and western blotting suggested that the downstream cell cycle-related genes were differentially expressed after MCM6 interference. Flow cytometric analysis revealed that neuroblastoma cells were blocked in G1/S phase after MCM6 interference. Conclusion MCM6 is considered to be the driving force of G1/S cell cycle progression, and it is also a prognostic marker and a potential novel therapeutic target in neuroblastoma. Supplementary Information The online version contains supplementary material available at 10.1186/s12885-021-08344-z.
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Affiliation(s)
- Yaoyao Gu
- Department of Pediatric Surgery, Xinhua Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, 200092, China.,Division of Pediatric Oncology, Shanghai Institute of Pediatric Research, Shanghai, 200092, China
| | - Xiaoxiao Hu
- Department of Pediatric Surgery, Xinhua Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, 200092, China.,Division of Pediatric Oncology, Shanghai Institute of Pediatric Research, Shanghai, 200092, China.,Department of Pediatric Surgery, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Xiaowei Liu
- Department of Pediatric Surgery, Xinhua Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, 200092, China.,Division of Pediatric Oncology, Shanghai Institute of Pediatric Research, Shanghai, 200092, China
| | - Cheng Cheng
- Department of Pediatric Surgery, Xinhua Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, 200092, China.,Division of Pediatric Oncology, Shanghai Institute of Pediatric Research, Shanghai, 200092, China
| | - Kai Chen
- Department of Pediatric Surgery, Xinhua Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, 200092, China.,Division of Pediatric Oncology, Shanghai Institute of Pediatric Research, Shanghai, 200092, China
| | - Yeming Wu
- Department of Pediatric Surgery, Xinhua Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, 200092, China.,Division of Pediatric Oncology, Shanghai Institute of Pediatric Research, Shanghai, 200092, China.,Department of Pediatric Surgery, Children's Hospital of Soochow University, Suzhou, 215003, China
| | - Zhixiang Wu
- Department of Pediatric Surgery, Xinhua Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, 200092, China. .,Division of Pediatric Oncology, Shanghai Institute of Pediatric Research, Shanghai, 200092, China. .,Department of Pediatric Surgery, Children's Hospital of Soochow University, Suzhou, 215003, China.
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38
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Guilliam TA. Mechanisms for Maintaining Eukaryotic Replisome Progression in the Presence of DNA Damage. Front Mol Biosci 2021; 8:712971. [PMID: 34295925 PMCID: PMC8290200 DOI: 10.3389/fmolb.2021.712971] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 06/25/2021] [Indexed: 12/04/2022] Open
Abstract
The eukaryotic replisome coordinates template unwinding and nascent-strand synthesis to drive DNA replication fork progression and complete efficient genome duplication. During its advancement along the parental template, each replisome may encounter an array of obstacles including damaged and structured DNA that impede its progression and threaten genome stability. A number of mechanisms exist to permit replisomes to overcome such obstacles, maintain their progression, and prevent fork collapse. A combination of recent advances in structural, biochemical, and single-molecule approaches have illuminated the architecture of the replisome during unperturbed replication, rationalised the impact of impediments to fork progression, and enhanced our understanding of DNA damage tolerance mechanisms and their regulation. This review focusses on these studies to provide an updated overview of the mechanisms that support replisomes to maintain their progression on an imperfect template.
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Affiliation(s)
- Thomas A. Guilliam
- Division of Protein and Nucleic Acid Chemistry, Medical Research Council Laboratory of Molecular Biology, Cambridge, United Kingdom
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39
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Li Y, Zou J, Zhang Q, Quan F, Cao L, Zhang X, Liu J, Wu D. Systemic Analysis of the DNA Replication Regulator MCM Complex in Ovarian Cancer and Its Prognostic Value. Front Oncol 2021; 11:681261. [PMID: 34178669 PMCID: PMC8220296 DOI: 10.3389/fonc.2021.681261] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 05/18/2021] [Indexed: 01/11/2023] Open
Abstract
Microliposome maintenance (MCM) 2, MCM3, MCM4, MCM5, MCM6, and MCM7 are DNA replication regulators and are involved in the progression of multiple cancer types, but their role in ovarian cancer is still unclear. The purpose of this study is to clarify the biological function and prognostic value of the MCM complex in ovarian cancer (OS) progression. We analyzed DNA alterations, mRNA and protein levels, protein structure, PPI network, functional enrichment, and prognostic value in OC based on the Oncomine, cBioPortal, TCGA, CPTAC, PDB, GeneMANIA, DAVID, KEGG, and GSCALite databases. The results indicated that the protein levels of these DNA replication regulators were increased significantly. Moreover, survival analysis showed a prognostic signature based on the MCM complex, which performed moderately well in terms of OS prognostic prediction. Additionally, protein structure, functional enrichment, and PPI network analyses indicated that the MCM complex synergistically promoted OC progression by accelerating DNA replication and the cell cycle. In conclusion, our study suggested that the MCM complex might be a potential target and prognostic marker for OC patients.
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Affiliation(s)
- Yukun Li
- Department of Obstetrics and Gynecology, The Second Affiliated Hospital of University of South China, Hengyang, China
| | - Juan Zou
- Department of Obstetrics and Gynecology, The Second Affiliated Hospital of University of South China, Hengyang, China
| | - Qunfeng Zhang
- Department of Obstetrics and Gynecology, The Second Affiliated Hospital of University of South China, Hengyang, China
| | - Feifei Quan
- Department of Obstetrics and Gynecology, Foshan First People's Hospital, Foshan, China
| | - Lu Cao
- Department of Obstetrics and Gynecology, The Second Affiliated Hospital of University of South China, Hengyang, China
| | - Xiaodi Zhang
- Department of Obstetrics and Gynecology, The Second Affiliated Hospital of University of South China, Hengyang, China
| | - Jue Liu
- Department of Obstetrics and Gynecology, The Second Affiliated Hospital of University of South China, Hengyang, China
| | - Daichao Wu
- Clinical Anatomy & Reproductive Medicine Application Institute, Department of Histology and Embryology, University of South China, Hengyang, China.,Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD, United States
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40
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Meagher M, Spence MN, Enemark EJ. Structure of a dimer of the Sulfolobus solfataricus MCM N-terminal domain reveals a potential role in MCM ring opening. Acta Crystallogr F Struct Biol Commun 2021; 77:177-186. [PMID: 34100776 PMCID: PMC8186412 DOI: 10.1107/s2053230x21005331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 05/20/2021] [Indexed: 11/11/2022] Open
Abstract
Cells strongly regulate DNA replication to ensure genomic stability and prevent several diseases, including cancers. Eukaryotes and archaea strictly control DNA-replication initiation by the regulated loading of hexameric minichromosome maintenance (MCM) rings to encircle both strands of the DNA double helix followed by regulated activation of the loaded rings such that they then encircle one DNA strand while excluding the other. Both steps involve an open/closed ring transformation, allowing DNA strands to enter or exit. Here, the crystal structure of a dimer of the N-terminal domain of Sulfolobus solfataricus MCM with an intersubunit interface that is more extensive than in closed-ring structures, while including common interactions to enable facile interconversion, is presented. It is shown that the identified interface could stabilize open MCM rings by compensating for lost interactions at an open neighbor interface and that the prior open-ring cryo-EM structure of MCM loading has a similar extended interface adjacent to its open interface.
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Affiliation(s)
- Martin Meagher
- Structural Biology, St Jude Children’s Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105, USA
| | - Madison N. Spence
- Structural Biology, St Jude Children’s Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105, USA
| | - Eric J. Enemark
- Structural Biology, St Jude Children’s Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105, USA
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, 4301 W. Markham Street, Slot 516, Little Rock, AR 72205, USA
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41
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Replication initiation: Implications in genome integrity. DNA Repair (Amst) 2021; 103:103131. [PMID: 33992866 DOI: 10.1016/j.dnarep.2021.103131] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 05/07/2021] [Accepted: 05/07/2021] [Indexed: 02/01/2023]
Abstract
In every cell cycle, billions of nucleotides need to be duplicated within hours, with extraordinary precision and accuracy. The molecular mechanism by which cells regulate the replication event is very complicated, and the entire process begins way before the onset of S phase. During the G1 phase of the cell cycle, cells prepare by assembling essential replication factors to establish the pre-replicative complex at origins, sites that dictate where replication would initiate during S phase. During S phase, the replication process is tightly coupled with the DNA repair system to ensure the fidelity of replication. Defects in replication and any error must be recognized by DNA damage response and checkpoint signaling pathways in order to halt the cell cycle before cells are allowed to divide. The coordination of these processes throughout the cell cycle is therefore critical to achieve genomic integrity and prevent diseases. In this review, we focus on the current understanding of how the replication initiation events are regulated to achieve genome stability.
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42
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Huang C, Lei C, Pan B, Fang S, Chen Y, Cao W, Liu L. Potential Prospective Biomarkers for Non-small Cell Lung Cancer: Mini-Chromosome Maintenance Proteins. Front Genet 2021; 12:587017. [PMID: 33936158 PMCID: PMC8079985 DOI: 10.3389/fgene.2021.587017] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 03/18/2021] [Indexed: 11/13/2022] Open
Abstract
Minichromosome maintenance proteins (MCMs) are considered to be essential factors coupling DNA replication to both cell cycle progression and checkpoint regulation. Previous studies have shown that dysregulation of MCMs are implicated in tumorigenesis of lung cancer. However, the distinct expression/mutation patterns and prognostic values of MCMs in lung cancer have yet to be systematically elucidated. In the present study, we analyzed the transcriptional levels, mutations, and prognostic value of MCM1-10 in non-small cell lung cancer (NSCLC) patients using multiple bioinformatics tools, including ONCOMINE, GEPIA, Kaplan-Meier Plotter, cBioPortal, and GESA. The analysis results from GEPIA dataset showed that MCM2/4/10 was significantly high expressed in both lung adenocarcinoma (LUAD) and squamous cell lung carcinomas (LUSCs). Meanwhile, the expression levels of MCM2/4/6/7/8 were associated with advanced tumor stages. Subsequent survival analysis using the Kaplan-Meier Plotter indicated that high expression levels of MCM1/2/3/4/5/6/7/8/10 were associated with worse overall survival (OS), while high expression level of MCM9 predicted better OS in these patients. Furthermore, we experimentally validated overexpression of MCM2 and MCM4 in NSCLC, thus the results from this study support a view that they may serve as potential prospective biomarkers to identify high-risk subgroups of NSCLC patients.
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Affiliation(s)
- Chen Huang
- Department of Gastrointestinal Cancer Biology, Tianjin Medical University Cancer Institute & Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy-Tianjin, Tianjin's Clinical Research Center for Cancer, Tianjin, China
| | - Chuqi Lei
- Hunan Provincial Key Lab on Bioinformatics, School of Computer Science and Engineering, Central South University, Changsha, China
| | - Boyu Pan
- Department of Gastrointestinal Cancer Biology, Tianjin Medical University Cancer Institute & Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy-Tianjin, Tianjin's Clinical Research Center for Cancer, Tianjin, China
| | - Senbiao Fang
- Hunan Provincial Key Lab on Bioinformatics, School of Computer Science and Engineering, Central South University, Changsha, China
| | - Yubao Chen
- Department of Computational Biology, Beijing Computing Center, Beijing, China
| | - Wenfeng Cao
- Department of Pathology, Tianjin Medical University Cancer Institute & Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy-Tianjin, Tianjin's Clinical Research Center for Cancer, Tianjin, China
| | - Liren Liu
- Department of Gastrointestinal Cancer Biology, Tianjin Medical University Cancer Institute & Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy-Tianjin, Tianjin's Clinical Research Center for Cancer, Tianjin, China
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43
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Abstract
The faithful and timely copying of DNA by molecular machines known as replisomes depends on a disparate suite of enzymes and scaffolding factors working together in a highly orchestrated manner. Large, dynamic protein-nucleic acid assemblies that selectively morph between distinct conformations and compositional states underpin this critical cellular process. In this article, we discuss recent progress outlining the physical basis of replisome construction and progression in eukaryotes.
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Affiliation(s)
- Ilan Attali
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, USA;
| | - Michael R Botchan
- Department of Molecular and Cell Biology, University of California, Berkeley, California 94720, USA
| | - James M Berger
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, USA;
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44
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Arsenic hexoxide has differential effects on cell proliferation and genome-wide gene expression in human primary mammary epithelial and MCF7 cells. Sci Rep 2021; 11:3761. [PMID: 33580144 PMCID: PMC7881197 DOI: 10.1038/s41598-021-82551-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Accepted: 01/21/2021] [Indexed: 02/06/2023] Open
Abstract
Arsenic is reportedly a biphasic inorganic compound for its toxicity and anticancer effects in humans. Recent studies have shown that certain arsenic compounds including arsenic hexoxide (AS4O6; hereafter, AS6) induce programmed cell death and cell cycle arrest in human cancer cells and murine cancer models. However, the mechanisms by which AS6 suppresses cancer cells are incompletely understood. In this study, we report the mechanisms of AS6 through transcriptome analyses. In particular, the cytotoxicity and global gene expression regulation by AS6 were compared in human normal and cancer breast epithelial cells. Using RNA-sequencing and bioinformatics analyses, differentially expressed genes in significantly affected biological pathways in these cell types were validated by real-time quantitative polymerase chain reaction and immunoblotting assays. Our data show markedly differential effects of AS6 on cytotoxicity and gene expression in human mammary epithelial normal cells (HUMEC) and Michigan Cancer Foundation 7 (MCF7), a human mammary epithelial cancer cell line. AS6 selectively arrests cell growth and induces cell death in MCF7 cells without affecting the growth of HUMEC in a dose-dependent manner. AS6 alters the transcription of a large number of genes in MCF7 cells, but much fewer genes in HUMEC. Importantly, we found that the cell proliferation, cell cycle, and DNA repair pathways are significantly suppressed whereas cellular stress response and apoptotic pathways increase in AS6-treated MCF7 cells. Together, we provide the first evidence of differential effects of AS6 on normal and cancerous breast epithelial cells, suggesting that AS6 at moderate concentrations induces cell cycle arrest and apoptosis through modulating genome-wide gene expression, leading to compromised DNA repair and increased genome instability selectively in human breast cancer cells.
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45
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Mohammed Khalid AA, Parisse P, Medagli B, Onesti S, Casalis L. Atomic Force Microscopy Investigation of the Interactions between the MCM Helicase and DNA. MATERIALS 2021; 14:ma14030687. [PMID: 33540751 PMCID: PMC7867263 DOI: 10.3390/ma14030687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 01/21/2021] [Accepted: 01/26/2021] [Indexed: 11/16/2022]
Abstract
The MCM (minichromosome maintenance) protein complex forms an hexameric ring and has a key role in the replication machinery of Eukaryotes and Archaea, where it functions as the replicative helicase opening up the DNA double helix ahead of the polymerases. Here, we present a study of the interaction between DNA and the archaeal MCM complex from Methanothermobacter thermautotrophicus by means of atomic force microscopy (AFM) single molecule imaging. We first optimized the protocol (surface treatment and buffer conditions) to obtain AFM images of surface-equilibrated DNA molecules before and after the interaction with the protein complex. We discriminated between two modes of interaction, one in which the protein induces a sharp bend in the DNA, and one where there is no bending. We found that the presence of the MCM complex also affects the DNA contour length. A possible interpretation of the observed behavior is that in one case the hexameric ring encircles the dsDNA, while in the other the nucleic acid wraps on the outside of the ring, undergoing a change of direction. We confirmed this topographical assignment by testing two mutants, one affecting the N-terminal β-hairpins projecting towards the central channel, and thus preventing DNA loading, the other lacking an external subdomain and thus preventing wrapping. The statistical analysis of the distribution of the protein complexes between the two modes, together with the dissection of the changes of DNA contour length and binding angle upon interaction, for the wild type and the two mutants, is consistent with the hypothesis. We discuss the results in view of the various modes of nucleic acid interactions that have been proposed for both archaeal and eukaryotic MCM complexes.
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Affiliation(s)
- Amna Abdalla Mohammed Khalid
- Elettra-Sincrotrone Trieste, 34149 Trieste, Italy; (A.A.M.K.); (B.M.)
- Department of Physics, PhD School in Nanotechnology, University of Trieste, 34127 Trieste, Italy
| | - Pietro Parisse
- Elettra-Sincrotrone Trieste, 34149 Trieste, Italy; (A.A.M.K.); (B.M.)
- Istituto Officina dei Materiali, Consiglio Nazionale delle Ricerche (IOM-CNR), 34149 Trieste, Italy
- Correspondence: (P.P.); (S.O.); (L.C.)
| | - Barbara Medagli
- Elettra-Sincrotrone Trieste, 34149 Trieste, Italy; (A.A.M.K.); (B.M.)
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, 34127 Trieste, Italy
| | - Silvia Onesti
- Elettra-Sincrotrone Trieste, 34149 Trieste, Italy; (A.A.M.K.); (B.M.)
- Correspondence: (P.P.); (S.O.); (L.C.)
| | - Loredana Casalis
- Elettra-Sincrotrone Trieste, 34149 Trieste, Italy; (A.A.M.K.); (B.M.)
- Correspondence: (P.P.); (S.O.); (L.C.)
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46
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Jessop M, Felix J, Gutsche I. AAA+ ATPases: structural insertions under the magnifying glass. Curr Opin Struct Biol 2021; 66:119-128. [PMID: 33246198 PMCID: PMC7973254 DOI: 10.1016/j.sbi.2020.10.027] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 10/19/2020] [Accepted: 10/27/2020] [Indexed: 11/29/2022]
Abstract
AAA+ ATPases are a diverse protein superfamily which power a vast number of cellular processes, from protein degradation to genome replication and ribosome biogenesis. The latest advances in cryo-EM have resulted in a spectacular increase in the number and quality of AAA+ ATPase structures. This abundance of new information enables closer examination of different types of structural insertions into the conserved core, revealing discrepancies in the current classification of AAA+ modules into clades. Additionally, combined with biochemical data, it has allowed rapid progress in our understanding of structure-functional relationships and provided arguments both in favour and against the existence of a unifying molecular mechanism for the ATPase activity and action on substrates, stimulating further intensive research.
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Affiliation(s)
- Matthew Jessop
- Institut de Biologie Structurale, Univ. Grenoble Alpes, CEA, CNRS, IBS, 71 Avenue des martyrs, F-38044 Grenoble, France.
| | - Jan Felix
- Institut de Biologie Structurale, Univ. Grenoble Alpes, CEA, CNRS, IBS, 71 Avenue des martyrs, F-38044 Grenoble, France
| | - Irina Gutsche
- Institut de Biologie Structurale, Univ. Grenoble Alpes, CEA, CNRS, IBS, 71 Avenue des martyrs, F-38044 Grenoble, France.
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47
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Anatomy of a twin DNA replication factory. Biochem Soc Trans 2020; 48:2769-2778. [PMID: 33300972 PMCID: PMC7752080 DOI: 10.1042/bst20200640] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 11/13/2020] [Accepted: 11/17/2020] [Indexed: 11/30/2022]
Abstract
The replication of DNA in chromosomes is initiated at sequences called origins at which two replisome machines are assembled at replication forks that move in opposite directions. Interestingly, in vivo studies observe that the two replication forks remain fastened together, often referred to as a replication factory. Replication factories containing two replisomes are well documented in cellular studies of bacteria (Escherichia coli and Bacillus subtilis) and the eukaryote, Saccharomyces cerevisiae. This basic twin replisome factory architecture may also be preserved in higher eukaryotes. Despite many years of documenting the existence of replication factories, the molecular details of how the two replisome machines are tethered together has been completely unknown in any organism. Recent structural studies shed new light on the architecture of a eukaryote replisome factory, which brings with it a new twist on how a replication factory may function.
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48
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Schauer GD, Spenkelink LM, Lewis JS, Yurieva O, Mueller SH, van Oijen AM, O'Donnell ME. Replisome bypass of a protein-based R-loop block by Pif1. Proc Natl Acad Sci U S A 2020; 117:30354-30361. [PMID: 33199603 PMCID: PMC7720201 DOI: 10.1073/pnas.2020189117] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Efficient and faithful replication of the genome is essential to maintain genome stability. Replication is carried out by a multiprotein complex called the replisome, which encounters numerous obstacles to its progression. Failure to bypass these obstacles results in genome instability and may facilitate errors leading to disease. Cells use accessory helicases that help the replisome bypass difficult barriers. All eukaryotes contain the accessory helicase Pif1, which tracks in a 5'-3' direction on single-stranded DNA and plays a role in genome maintenance processes. Here, we reveal a previously unknown role for Pif1 in replication barrier bypass. We use an in vitro reconstituted Saccharomyces cerevisiae replisome to demonstrate that Pif1 enables the replisome to bypass an inactive (i.e., dead) Cas9 (dCas9) R-loop barrier. Interestingly, dCas9 R-loops targeted to either strand are bypassed with similar efficiency. Furthermore, we employed a single-molecule fluorescence visualization technique to show that Pif1 facilitates this bypass by enabling the simultaneous removal of the dCas9 protein and the R-loop. We propose that Pif1 is a general displacement helicase for replication bypass of both R-loops and protein blocks.
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Affiliation(s)
- Grant D Schauer
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523;
| | - Lisanne M Spenkelink
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia
- Illawarra Health & Medical Research Institute, Wollongong, NSW 2522, Australia
| | - Jacob S Lewis
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia
- Illawarra Health & Medical Research Institute, Wollongong, NSW 2522, Australia
| | - Olga Yurieva
- HHMI, Rockefeller University, New York, NY 10065
- Laboratory of DNA Replication, Rockefeller University, New York, NY 10065
| | - Stefan H Mueller
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia
- Illawarra Health & Medical Research Institute, Wollongong, NSW 2522, Australia
| | - Antoine M van Oijen
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia;
- Illawarra Health & Medical Research Institute, Wollongong, NSW 2522, Australia
| | - Michael E O'Donnell
- HHMI, Rockefeller University, New York, NY 10065;
- Laboratory of DNA Replication, Rockefeller University, New York, NY 10065
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49
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Niu Y, Suzuki H, Hosford CJ, Walz T, Chappie JS. Structural asymmetry governs the assembly and GTPase activity of McrBC restriction complexes. Nat Commun 2020; 11:5907. [PMID: 33219217 PMCID: PMC7680126 DOI: 10.1038/s41467-020-19735-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 10/26/2020] [Indexed: 01/21/2023] Open
Abstract
McrBC complexes are motor-driven nucleases functioning in bacterial self-defense by cleaving foreign DNA. The GTP-specific AAA + protein McrB powers translocation along DNA and its hydrolysis activity is stimulated by its partner nuclease McrC. Here, we report cryo-EM structures of Thermococcus gammatolerans McrB and McrBC, and E. coli McrBC. The McrB hexamers, containing the necessary catalytic machinery for basal GTP hydrolysis, are intrinsically asymmetric. This asymmetry directs McrC binding so that it engages a single active site, where it then uses an arginine/lysine-mediated hydrogen-bonding network to reposition the asparagine in the McrB signature motif for optimal catalytic function. While the two McrBC complexes use different DNA-binding domains, these contribute to the same general GTP-recognition mechanism employed by all G proteins. Asymmetry also induces distinct inter-subunit interactions around the ring, suggesting a coordinated and directional GTP-hydrolysis cycle. Our data provide insights into the conserved molecular mechanisms governing McrB family AAA + motors.
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Affiliation(s)
- Yiming Niu
- Department of Molecular Medicine, Cornell University, Ithaca, NY, USA
- Laboratory of Molecular Electron Microscopy, The Rockefeller University, New York, NY, USA
- Laboratory Molecular Neurobiology and Biophysics, The Rockefeller University, New York, NY, USA
| | - Hiroshi Suzuki
- Laboratory of Molecular Electron Microscopy, The Rockefeller University, New York, NY, USA
- Advanced Research Institute, Tokyo Medical and Dental University, Tokyo, Japan
| | - Christopher J Hosford
- Department of Molecular Medicine, Cornell University, Ithaca, NY, USA
- New England Biolabs, Inc., Ipswich, MA, USA
| | - Thomas Walz
- Laboratory of Molecular Electron Microscopy, The Rockefeller University, New York, NY, USA.
| | - Joshua S Chappie
- Department of Molecular Medicine, Cornell University, Ithaca, NY, USA.
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50
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Enhanced CAR-T activity against established tumors by polarizing human T cells to secrete interleukin-9. Nat Commun 2020; 11:5902. [PMID: 33214555 PMCID: PMC7677397 DOI: 10.1038/s41467-020-19672-2] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 10/21/2020] [Indexed: 01/04/2023] Open
Abstract
CAR-T cell therapy is effective for hematologic malignancies. However, considerable numbers of patients relapse after the treatment, partially due to poor expansion and limited persistence of CAR-T cells in vivo. Here, we demonstrate that human CAR-T cells polarized and expanded under a Th9-culture condition (T9 CAR-T) have an enhanced antitumor activity against established tumors. Compared to IL2-polarized (T1) cells, T9 CAR-T cells secrete IL9 but little IFN-γ, express central memory phenotype and lower levels of exhaustion markers, and display robust proliferative capacity. Consequently, T9 CAR-T cells mediate a greater antitumor activity than T1 CAR-T cells against established hematologic and solid tumors in vivo. After transfer, T9 CAR-T cells migrate effectively to tumors, differentiate to IFN-γ and granzyme-B secreting effector memory T cells but remain as long-lived and hyperproliferative T cells. Our findings are important for the improvement of CAR-T cell-based immunotherapy for human cancers. Antigen-specific IL9-secreting CD4 Th9 and CD8 Tc9 cells have been previously characterized for their anti-tumour properties. Here, the authors show that ex vivo polarized Th9/Tc9 human CAR-T cells display increased anti-tumor activity in pre-clinical haematological and solid cancer models compared to conventional IL-2 activated CAR-T cells.
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