1
|
Sfeir A, Tijsterman M, McVey M. Microhomology-Mediated End-Joining Chronicles: Tracing the Evolutionary Footprints of Genome Protection. Annu Rev Cell Dev Biol 2024; 40:195-218. [PMID: 38857538 DOI: 10.1146/annurev-cellbio-111822-014426] [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] [Indexed: 06/12/2024]
Abstract
The fidelity of genetic information is essential for cellular function and viability. DNA double-strand breaks (DSBs) pose a significant threat to genome integrity, necessitating efficient repair mechanisms. While the predominant repair strategies are usually accurate, paradoxically, error-prone pathways also exist. This review explores recent advances and our understanding of microhomology-mediated end joining (MMEJ), an intrinsically mutagenic DSB repair pathway conserved across organisms. Central to MMEJ is the activity of DNA polymerase theta (Polθ), a specialized polymerase that fuels MMEJ mutagenicity. We examine the molecular intricacies underlying MMEJ activity and discuss its function during mitosis, where the activity of Polθ emerges as a last-ditch effort to resolve persistent DSBs, especially when homologous recombination is compromised. We explore the promising therapeutic applications of targeting Polθ in cancer treatment and genome editing. Lastly, we discuss the evolutionary consequences of MMEJ, highlighting its delicate balance between protecting genome integrity and driving genomic diversity.
Collapse
Affiliation(s)
- Agnel Sfeir
- Molecular Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA;
| | - Marcel Tijsterman
- Department of Human Genetics, Leiden University Medical Center; Institute of Biology Leiden, Leiden University, Leiden, The Netherlands;
| | - Mitch McVey
- Department of Biology, Tufts University, Medford, Massachusetts, USA;
| |
Collapse
|
2
|
Blanch JR, Krishnamurthy M, McVey M. A non-tethering role for the Drosophila Pol θ linker domain in promoting damage resolution. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.27.609911. [PMID: 39253446 PMCID: PMC11383001 DOI: 10.1101/2024.08.27.609911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 09/11/2024]
Abstract
DNA polymerase theta ( Pol θ ) is an error-prone translesion polymerase that becomes crucial for DNA double-strand break repair when cells are deficient in homologous recombination or non-homologous end joining. In some organisms, Pol θ also promotes tolerance of DNA interstrand crosslinks. Due to its importance in DNA damage tolerance, Pol θ is an emerging target for treatment of cancer and disease. Prior work has characterized the functions of the Pol θ helicase-like and polymerase domains, but the roles of the linker domain are largely unknown. Here, we show that the Drosophila melanogaster Pol θ linker domain promotes egg development and is required for tolerance of DNA double-strand breaks and interstrand crosslinks. While a linker domain with scrambled amino acid residues is sufficient for DNA repair, replacement of the linker with part of the Homo sapiens Pol θ linker or a disordered region from the FUS RNA-binding protein does not restore function. These results demonstrate that the linker domain is not simply a random tether between the helicase-like and polymerase domains. Furthermore, they suggest that intrinsic amino acid residue properties, rather than protein interaction motifs, are more critical for Pol θ linker functions in DNA repair.
Collapse
Affiliation(s)
- Justin R Blanch
- Department of Biology, Tufts University, Medford, Massachusetts, 02155, United States of America
| | - Manan Krishnamurthy
- Department of Biology, Tufts University, Medford, Massachusetts, 02155, United States of America
- Icahn School of Medicine at Mount Sinai, New York City, New York, 10029, United States of America
| | - Mitch McVey
- Department of Biology, Tufts University, Medford, Massachusetts, 02155, United States of America
| |
Collapse
|
3
|
Ito F, Li Z, Minakhin L, Chandramouly G, Tyagi M, Betsch R, Krais JJ, Taberi B, Vekariya U, Calbert M, Skorski T, Johnson N, Chen XS, Pomerantz RT. Structural basis for a Polθ helicase small-molecule inhibitor revealed by cryo-EM. Nat Commun 2024; 15:7003. [PMID: 39143110 PMCID: PMC11324745 DOI: 10.1038/s41467-024-51351-4] [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: 08/11/2023] [Accepted: 08/05/2024] [Indexed: 08/16/2024] Open
Abstract
DNA polymerase theta (Polθ) is a DNA helicase-polymerase protein that facilitates DNA repair and is synthetic lethal with homology-directed repair (HDR) factors. Thus, Polθ is a promising precision oncology drug-target in HDR-deficient cancers. Here, we characterize the binding and mechanism of action of a Polθ helicase (Polθ-hel) small-molecule inhibitor (AB25583) using cryo-EM. AB25583 exhibits 6 nM IC50 against Polθ-hel, selectively kills BRCA1/2-deficient cells, and acts synergistically with olaparib in cancer cells harboring pathogenic BRCA1/2 mutations. Cryo-EM uncovers predominantly dimeric Polθ-hel:AB25583 complex structures at 3.0-3.2 Å. The structures reveal a binding-pocket deep inside the helicase central-channel, which underscores the high specificity and potency of AB25583. The cryo-EM structures in conjunction with biochemical data indicate that AB25583 inhibits the ATPase activity of Polθ-hel helicase via an allosteric mechanism. These detailed structural data and insights about AB25583 inhibition pave the way for accelerating drug development targeting Polθ-hel in HDR-deficient cancers.
Collapse
Affiliation(s)
- Fumiaki Ito
- Molecular and Computational Biology, Department of Biological Sciences and Chemistry, University of Southern California, Los Angeles, California, CA, 90089, USA
| | - Ziyuan Li
- Molecular and Computational Biology, Department of Biological Sciences and Chemistry, University of Southern California, Los Angeles, California, CA, 90089, USA
| | - Leonid Minakhin
- Department of Biochemistry and Molecular Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - Gurushankar Chandramouly
- Department of Biochemistry and Molecular Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - Mrityunjay Tyagi
- Department of Biochemistry and Molecular Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - Robert Betsch
- Nuclear Dynamics Program, Fox Chase Cancer Center, Philadelphia, PA, 19111, USA
| | - John J Krais
- Nuclear Dynamics Program, Fox Chase Cancer Center, Philadelphia, PA, 19111, USA
| | - Bernadette Taberi
- Department of Biochemistry and Molecular Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - Umeshkumar Vekariya
- Fels Cancer Institute for Personalized Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, 19140, USA
| | - Marissa Calbert
- Department of Biochemistry and Molecular Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - Tomasz Skorski
- Fels Cancer Institute for Personalized Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, 19140, USA
| | - Neil Johnson
- Nuclear Dynamics Program, Fox Chase Cancer Center, Philadelphia, PA, 19111, USA
| | - Xiaojiang S Chen
- Molecular and Computational Biology, Department of Biological Sciences and Chemistry, University of Southern California, Los Angeles, California, CA, 90089, USA.
| | - Richard T Pomerantz
- Department of Biochemistry and Molecular Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, 19107, USA.
| |
Collapse
|
4
|
Vekariya U, Minakhin L, Chandramouly G, Tyagi M, Kent T, Sullivan-Reed K, Atkins J, Ralph D, Nieborowska-Skorska M, Kukuyan AM, Tang HY, Pomerantz RT, Skorski T. PARG is essential for Polθ-mediated DNA end-joining by removing repressive poly-ADP-ribose marks. Nat Commun 2024; 15:5822. [PMID: 38987289 PMCID: PMC11236980 DOI: 10.1038/s41467-024-50158-7] [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: 08/29/2023] [Accepted: 06/27/2024] [Indexed: 07/12/2024] Open
Abstract
DNA polymerase theta (Polθ)-mediated end-joining (TMEJ) repairs DNA double-strand breaks and confers resistance to genotoxic agents. How Polθ is regulated at the molecular level to exert TMEJ remains poorly characterized. We find that Polθ interacts with and is PARylated by PARP1 in a HPF1-independent manner. PARP1 recruits Polθ to the vicinity of DNA damage via PARylation dependent liquid demixing, however, PARylated Polθ cannot perform TMEJ due to its inability to bind DNA. PARG-mediated de-PARylation of Polθ reactivates its DNA binding and end-joining activities. Consistent with this, PARG is essential for TMEJ and the temporal recruitment of PARG to DNA damage corresponds with TMEJ activation and dissipation of PARP1 and PAR. In conclusion, we show a two-step spatiotemporal mechanism of TMEJ regulation. First, PARP1 PARylates Polθ and facilitates its recruitment to DNA damage sites in an inactivated state. PARG subsequently activates TMEJ by removing repressive PAR marks on Polθ.
Collapse
Affiliation(s)
- Umeshkumar Vekariya
- Fels Cancer Institute for Personalized Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, 19140, USA
| | - Leonid Minakhin
- Thomas Jefferson University, Sidney Kimmel Cancer Center, Department of Biochemistry and Molecular Biology, Philadelphia, PA, 19107, USA
| | - Gurushankar Chandramouly
- Thomas Jefferson University, Sidney Kimmel Cancer Center, Department of Biochemistry and Molecular Biology, Philadelphia, PA, 19107, USA
| | - Mrityunjay Tyagi
- Thomas Jefferson University, Sidney Kimmel Cancer Center, Department of Biochemistry and Molecular Biology, Philadelphia, PA, 19107, USA
| | - Tatiana Kent
- Thomas Jefferson University, Sidney Kimmel Cancer Center, Department of Biochemistry and Molecular Biology, Philadelphia, PA, 19107, USA
| | - Katherine Sullivan-Reed
- Fels Cancer Institute for Personalized Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, 19140, USA
| | - Jessica Atkins
- Fels Cancer Institute for Personalized Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, 19140, USA
| | - Douglas Ralph
- Thomas Jefferson University, Sidney Kimmel Cancer Center, Department of Biochemistry and Molecular Biology, Philadelphia, PA, 19107, USA
| | - Margaret Nieborowska-Skorska
- Fels Cancer Institute for Personalized Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, 19140, USA
| | - Anna-Mariya Kukuyan
- Fels Cancer Institute for Personalized Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, 19140, USA
| | - Hsin-Yao Tang
- Proteomics and Metabolomics Facility, The Wistar Institute, Philadelphia, PA, 19104, USA
| | - Richard T Pomerantz
- Thomas Jefferson University, Sidney Kimmel Cancer Center, Department of Biochemistry and Molecular Biology, Philadelphia, PA, 19107, USA.
| | - Tomasz Skorski
- Fels Cancer Institute for Personalized Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, 19140, USA.
- Department of Cancer and Cellular Biology, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, 19140, USA.
- Nuclear Dynamics and Cancer Program, Fox Chase Cancer Center, Philadelphia, PA, USA.
| |
Collapse
|
5
|
Ito F, Li Z, Minakhin L, Khant HA, Pomerantz RT, Chen XS. Structural Basis for Polθ-Helicase DNA Binding and Microhomology-Mediated End-Joining. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.07.597860. [PMID: 38895274 PMCID: PMC11185775 DOI: 10.1101/2024.06.07.597860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
DNA double-strand breaks (DSBs) present a critical threat to genomic integrity, often precipitating genomic instability and oncogenesis. Repair of DSBs predominantly occurs through homologous recombination (HR) and non-homologous end joining (NHEJ). In HR-deficient cells, DNA polymerase theta (Polθ) becomes critical for DSB repair via microhomology-mediated end joining (MMEJ), also termed theta-mediated end joining (TMEJ). Thus, Polθ is synthetically lethal with BRCA1/2 and other HR factors, underscoring its potential as a therapeutic target in HR-deficient cancers. However, the molecular mechanisms governing Polθ-mediated MMEJ remain poorly understood. Here we present a series of cryo-electron microscopy structures of the Polθ helicase domain (Polθ-hel) in complex with DNA containing 3'-overhang. The structures reveal the sequential conformations adopted by Polθ-hel during the critical phases of DNA binding, microhomology searching, and microhomology annealing. The stepwise conformational changes within the Polθ-hel subdomains and its functional dimeric state are pivotal for aligning the 3'-overhangs, facilitating the microhomology search and subsequent annealing necessary for DSB repair via MMEJ. Our findings illustrate the essential molecular switches within Polθ-hel that orchestrate the MMEJ process in DSB repair, laying the groundwork for the development of targeted therapies against the Polθ-hel.
Collapse
Affiliation(s)
- Fumiaki Ito
- Molecular and Computational Biology, Department of Biological Sciences and Chemistry, University of Southern California, Los Angeles, California, 90089, USA
- Department of Microbiology, Immunology and Molecular Genetics
- California NanoSystems Institute, University of California, Los Angeles, CA90095, USA
| | - Ziyuan Li
- Molecular and Computational Biology, Department of Biological Sciences and Chemistry, University of Southern California, Los Angeles, California, 90089, USA
| | - Leonid Minakhin
- Department of Biochemistry and Molecular Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - Htet A. Khant
- USC Center of Excellence for Nano-Imaging, Viterbi School of Engineering, University of Southern California, Los Angeles, CA, 90089, USA
| | - Richard T. Pomerantz
- Department of Biochemistry and Molecular Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - Xiaojiang S. Chen
- Molecular and Computational Biology, Department of Biological Sciences and Chemistry, University of Southern California, Los Angeles, California, 90089, USA
| |
Collapse
|
6
|
Zerio CJ, Bai Y, Sosa-Alvarado BA, Guzi T, Lander GC. Human polymerase theta helicase positions DNA microhomologies for double-strand break repair. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.26.591388. [PMID: 38712090 PMCID: PMC11071473 DOI: 10.1101/2024.04.26.591388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
DNA double-strand breaks occur in all human cells on a daily basis and must be repaired with high fidelity to minimize genomic instability1. Deficiencies in high-fidelity DNA repair by homologous recombination lead to dependence on DNA polymerase theta, which identifies DNA microhomologies in 3' single-stranded DNA overhangs and anneals them to initiate error-prone double-strand break repair. The resulting genomic instability is associated with numerous cancers, thereby making this polymerase an attractive therapeutic target2,3. However, despite the biomedical importance of polymerase theta, the molecular details of how it initiates DNA break repair remain unclear4,5. Here we present cryo-electron microscopy structures of the polymerase theta helicase domain bound to microhomology-containing DNA, revealing DNA-induced rearrangements of the helicase that enable DNA repair. Our structures show that DNA-bound helicase dimers facilitate a microhomology search that positions 3' single-stranded DNA ends in proximity to align complementary base pairs and anneal DNA microhomology. We define the molecular determinants that enable the polymerase theta helicase domain to identify and pair DNA microhomologies to initiate mutagenic DNA repair, providing mechanistic insights into therapeutic targeting of these interactions.
Collapse
Affiliation(s)
- Christopher J. Zerio
- Department of Integrative Structural and Computational Biology, Scripps Research; La Jolla, CA, USA
| | | | | | | | - Gabriel C. Lander
- Department of Integrative Structural and Computational Biology, Scripps Research; La Jolla, CA, USA
| |
Collapse
|
7
|
Fijen C, Drogalis Beckham L, Terino D, Li Y, Ramsden DA, Wood RD, Doublié S, Rothenberg E. Sequential requirements for distinct Polθ domains during theta-mediated end joining. Mol Cell 2024; 84:1460-1474.e6. [PMID: 38640894 PMCID: PMC11031631 DOI: 10.1016/j.molcel.2024.03.010] [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: 03/29/2023] [Revised: 01/10/2024] [Accepted: 03/12/2024] [Indexed: 04/21/2024]
Abstract
DNA polymerase θ (Polθ) plays a central role in a DNA double-strand break repair pathway termed theta-mediated end joining (TMEJ). TMEJ functions by pairing short-sequence "microhomologies" (MHs) in single-stranded DNA at each end of a break and subsequently initiating DNA synthesis. It is not known how the Polθ helicase domain (HD) and polymerase domain (PD) operate to bring together MHs and facilitate repair. To resolve these transient processes in real time, we utilized in vitro single-molecule FRET approaches and biochemical analyses. We find that the Polθ-HD mediates the initial capture of two ssDNA strands, bringing them in close proximity. The Polθ-PD binds and stabilizes pre-annealed MHs to form a synaptic complex (SC) and initiate repair synthesis. Individual synthesis reactions show that Polθ is inherently non-processive, accounting for complex mutational patterns during TMEJ. Binding of Polθ-PD to stem-loop-forming sequences can substantially limit synapsis, depending on the available dNTPs and sequence context.
Collapse
Affiliation(s)
- Carel Fijen
- Department of Biochemistry and Molecular Pharmacology, NYU Grossman School of Medicine, New York, NY 10016, USA.
| | - Lea Drogalis Beckham
- Department of Microbiology and Molecular Genetics, University of Vermont, Burlington, VT 05405, USA
| | - Dante Terino
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Yuzhen Li
- Department of Epigenetics and Molecular Carcinogenesis, University of Texas MD Anderson Cancer Center, Houston, TX 77230, USA
| | - Dale A Ramsden
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Richard D Wood
- Department of Epigenetics and Molecular Carcinogenesis, University of Texas MD Anderson Cancer Center, Houston, TX 77230, USA
| | - Sylvie Doublié
- Department of Microbiology and Molecular Genetics, University of Vermont, Burlington, VT 05405, USA
| | - Eli Rothenberg
- Department of Biochemistry and Molecular Pharmacology, NYU Grossman School of Medicine, New York, NY 10016, USA.
| |
Collapse
|
8
|
Stroik S, Luthman AJ, Ramsden DA. Templated insertions-DNA repair gets acrobatic. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2024; 65 Suppl 1:82-89. [PMID: 37438951 PMCID: PMC10962320 DOI: 10.1002/em.22564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 06/28/2023] [Accepted: 07/07/2023] [Indexed: 07/14/2023]
Abstract
Deletions associated with the repair of DNA double-strand breaks is a source of genetic alternation and a recognized source of disease-causing mutagenesis. Theta-mediated end joining is a DNA repair mechanism, which guarantees deletions by its employment of microhomology (MH) alignment to facilitate end joining. A lesser-characterized templated insertion ability of this pathway, on the other hand, is associated with both deletion and insertion. This mechanism is characterized by at least one round of polymerase θ-mediated synthesis, which does not result in successful repair, followed by a subsequent round of polymerase engagement and synthesis that does lead to repair. Here we focus on the mechanisms by which polymerase θ introduces these insertions-direct, inverse, and a new class which we have termed strand switching. We observe this new class of templated insertions at multiple loci and across multiple species, often at a comparable frequency to those previously characterized. Templated insertion mutations are often enriched in cancer genomes and repeat expansion disorders. This repair mechanism thus contributes to disease-associated mutagenesis, and may plausibly even promote disease. Characterization of the types of polymerase θ-dependent insertions can provide new insight into these diseases and clinical promise for treatment.
Collapse
Affiliation(s)
- Susanna Stroik
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Adam J. Luthman
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill NC, USA
| | - Dale A. Ramsden
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill NC, USA
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| |
Collapse
|
9
|
Kannan S, Gillespie SW, Picking WL, Picking WD, Lorson CL, Singh K. Inhibitors against DNA Polymerase I Family of Enzymes: Novel Targets and Opportunities. BIOLOGY 2024; 13:204. [PMID: 38666816 PMCID: PMC11048162 DOI: 10.3390/biology13040204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Revised: 03/18/2024] [Accepted: 03/20/2024] [Indexed: 04/28/2024]
Abstract
DNA polymerases replicate cellular genomes and/or participate in the maintenance of genome integrity. DNA polymerases sharing high sequence homology with E. coli DNA polymerase I (pol I) have been grouped in Family A. Pol I participates in Okazaki fragment maturation and in bacterial genome repair. Since its discovery in 1956, pol I has been extensively studied, primarily to gain deeper insights into the mechanism of DNA replication. As research on DNA polymerases advances, many novel functions of this group of polymerases are being uncovered. For example, human DNA polymerase θ (a Family A DNA pol) has been shown to synthesize DNA using RNA as a template, a function typically attributed to retroviral reverse transcriptase. Increased interest in drug discovery against pol θ has emerged due to its roles in cancer. Likewise, Pol I family enzymes also appear attractive as drug-development targets against microbial infections. Development of antimalarial compounds targeting apicoplast apPOL, an ortholog of Pol I, further extends the targeting of this family of enzymes. Here, we summarize reported drug-development efforts against Family A polymerases and future perspective regarding these enzymes as antibiotic targets. Recently developed techniques, such as artificial intelligence, can be used to facilitate the development of new drugs.
Collapse
Affiliation(s)
- Saathvik Kannan
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA; (S.K.); (S.W.G.); (W.L.P.); (W.D.P.); (C.L.L.)
| | - Samuel W. Gillespie
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA; (S.K.); (S.W.G.); (W.L.P.); (W.D.P.); (C.L.L.)
| | - Wendy L. Picking
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA; (S.K.); (S.W.G.); (W.L.P.); (W.D.P.); (C.L.L.)
- Department of Veterinary Pathobiology, University of Missouri, Columbia, MO 65211, USA
| | - William D. Picking
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA; (S.K.); (S.W.G.); (W.L.P.); (W.D.P.); (C.L.L.)
- Department of Veterinary Pathobiology, University of Missouri, Columbia, MO 65211, USA
| | - Christian L. Lorson
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA; (S.K.); (S.W.G.); (W.L.P.); (W.D.P.); (C.L.L.)
- Department of Veterinary Pathobiology, University of Missouri, Columbia, MO 65211, USA
| | - Kamal Singh
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA; (S.K.); (S.W.G.); (W.L.P.); (W.D.P.); (C.L.L.)
- Department of Veterinary Pathobiology, University of Missouri, Columbia, MO 65211, USA
| |
Collapse
|
10
|
Filandr F, Sarpe V, Raval S, Crowder DA, Khan MF, Douglas P, Coales S, Viner R, Syed A, Tainer JA, Lees-Miller SP, Schriemer DC. Automating data analysis for hydrogen/deuterium exchange mass spectrometry using data-independent acquisition methodology. Nat Commun 2024; 15:2200. [PMID: 38467655 PMCID: PMC10928179 DOI: 10.1038/s41467-024-46610-3] [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: 08/16/2023] [Accepted: 02/22/2024] [Indexed: 03/13/2024] Open
Abstract
We present a hydrogen/deuterium exchange workflow coupled to tandem mass spectrometry (HX-MS2) that supports the acquisition of peptide fragment ions alongside their peptide precursors. The approach enables true auto-curation of HX data by mining a rich set of deuterated fragments, generated by collisional-induced dissociation (CID), to simultaneously confirm the peptide ID and authenticate MS1-based deuteration calculations. The high redundancy provided by the fragments supports a confidence assessment of deuterium calculations using a combinatorial strategy. The approach requires data-independent acquisition (DIA) methods that are available on most MS platforms, making the switch to HX-MS2 straightforward. Importantly, we find that HX-DIA enables a proteomics-grade approach and wide-spread applications. Considerable time is saved through auto-curation and complex samples can now be characterized and at higher throughput. We illustrate these advantages in a drug binding analysis of the ultra-large protein kinase DNA-PKcs, isolated directly from mammalian cells.
Collapse
Affiliation(s)
- Frantisek Filandr
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Vladimir Sarpe
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Shaunak Raval
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, AB, T2N 4N1, Canada
- Department of Chemistry, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - D Alex Crowder
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Morgan F Khan
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Pauline Douglas
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Stephen Coales
- Trajan Scientific & Medical - Raleigh, Morrisville, NC, USA
| | - Rosa Viner
- Thermo Fisher Scientific, San Jose, CA, USA
| | - Aleem Syed
- Division of Radiation and Genome Instability, Department of Radiation Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, 02215, USA
| | - John A Tainer
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Susan P Lees-Miller
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - David C Schriemer
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, AB, T2N 4N1, Canada.
- Department of Chemistry, University of Calgary, Calgary, AB, T2N 4N1, Canada.
| |
Collapse
|
11
|
Syed A, Filandr F, Patterson-Fortin J, Bacolla A, Ravindranathan R, Zhou J, McDonald D, Albuhluli M, Verway-Cohen A, Newman J, Tsai MS, Jones D, Schriemer D, D’Andrea A, Tainer J. Novobiocin blocks nucleic acid binding to Polθ and inhibits stimulation of its ATPase activity. Nucleic Acids Res 2023; 51:9920-9937. [PMID: 37665033 PMCID: PMC10570058 DOI: 10.1093/nar/gkad727] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 08/10/2023] [Accepted: 08/24/2023] [Indexed: 09/05/2023] Open
Abstract
Polymerase theta (Polθ) acts in DNA replication and repair, and its inhibition is synthetic lethal in BRCA1 and BRCA2-deficient tumor cells. Novobiocin (NVB) is a first-in-class inhibitor of the Polθ ATPase activity, and it is currently being tested in clinical trials as an anti-cancer drug. Here, we investigated the molecular mechanism of NVB-mediated Polθ inhibition. Using hydrogen deuterium exchange-mass spectrometry (HX-MS), biophysical, biochemical, computational and cellular assays, we found NVB is a non-competitive inhibitor of ATP hydrolysis. NVB sugar group deletion resulted in decreased potency and reduced HX-MS interactions, supporting a specific NVB binding orientation. Collective results revealed that NVB binds to an allosteric site to block DNA binding, both in vitro and in cells. Comparisons of The Cancer Genome Atlas (TCGA) tumors and matched controls implied that POLQ upregulation in tumors stems from its role in replication stress responses to increased cell proliferation: this can now be tested in fifteen tumor types by NVB blocking ssDNA-stimulation of ATPase activity, required for Polθ function at replication forks and DNA damage sites. Structural and functional insights provided in this study suggest a path for developing NVB derivatives with improved potency for Polθ inhibition by targeting ssDNA binding with entropically constrained small molecules.
Collapse
Affiliation(s)
- Aleem Syed
- Division of Radiation and Genome Instability, Department of Radiation Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - Frantisek Filandr
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Jeffrey Patterson-Fortin
- Division of Radiation and Genome Instability, Department of Radiation Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - Albino Bacolla
- Department of Molecular and Cellular Oncology, Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Ramya Ravindranathan
- Division of Radiation and Genome Instability, Department of Radiation Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - Jia Zhou
- Division of Radiation and Genome Instability, Department of Radiation Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - Drew T McDonald
- Biological and System Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Mohammed E Albuhluli
- Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Amy Verway-Cohen
- Biological and System Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Joseph A Newman
- Center for Medicines Discovery, University of Oxford, OX1 3QU, UK
| | - Miaw-Sheue Tsai
- Biological and System Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Darin E Jones
- Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - David C Schriemer
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Alan D D’Andrea
- Division of Radiation and Genome Instability, Department of Radiation Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
- Center for DNA Damage and Repair, Dana-Farber Cancer Institute, Boston, MA 02215, USA
| | - John A Tainer
- Department of Molecular and Cellular Oncology, Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| |
Collapse
|
12
|
Czernecki D, Nourisson A, Legrand P, Delarue M. Reclassification of family A DNA polymerases reveals novel functional subfamilies and distinctive structural features. Nucleic Acids Res 2023; 51:4488-4507. [PMID: 37070157 PMCID: PMC10201439 DOI: 10.1093/nar/gkad242] [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: 08/02/2022] [Revised: 03/07/2023] [Accepted: 03/24/2023] [Indexed: 04/19/2023] Open
Abstract
Family A DNA polymerases (PolAs) form an important and well-studied class of extant polymerases participating in DNA replication and repair. Nonetheless, despite the characterization of multiple subfamilies in independent, dedicated works, their comprehensive classification thus far is missing. We therefore re-examine all presently available PolA sequences, converting their pairwise similarities into positions in Euclidean space, separating them into 19 major clusters. While 11 of them correspond to known subfamilies, eight had not been characterized before. For every group, we compile their general characteristics, examine their phylogenetic relationships and perform conservation analysis in the essential sequence motifs. While most subfamilies are linked to a particular domain of life (including phages), one subfamily appears in Bacteria, Archaea and Eukaryota. We also show that two new bacterial subfamilies contain functional enzymes. We use AlphaFold2 to generate high-confidence prediction models for all clusters lacking an experimentally determined structure. We identify new, conserved features involving structural alterations, ordered insertions and an apparent structural incorporation of a uracil-DNA glycosylase (UDG) domain. Finally, genetic and structural analyses of a subset of T7-like phages indicate a splitting of the 3'-5' exo and pol domains into two separate genes, observed in PolAs for the first time.
Collapse
Affiliation(s)
- Dariusz Czernecki
- Institut Pasteur, Université Paris Cité, CNRS UMR 3528, Unit of Architecture and Dynamics of Biological Macromolecules, 75015 Paris, France
- Sorbonne Université, Collège Doctoral, ED 515, 75005 Paris, France
| | - Antonin Nourisson
- Institut Pasteur, Université Paris Cité, CNRS UMR 3528, Unit of Architecture and Dynamics of Biological Macromolecules, 75015 Paris, France
- Sorbonne Université, Collège Doctoral, ED 515, 75005 Paris, France
| | - Pierre Legrand
- Institut Pasteur, Université Paris Cité, CNRS UMR 3528, Unit of Architecture and Dynamics of Biological Macromolecules, 75015 Paris, France
- Synchrotron SOLEIL, L’Orme des Merisiers, 91190 Saint-Aubin, France
| | - Marc Delarue
- Institut Pasteur, Université Paris Cité, CNRS UMR 3528, Unit of Architecture and Dynamics of Biological Macromolecules, 75015 Paris, France
| |
Collapse
|
13
|
Pismataro MC, Astolfi A, Barreca ML, Pacetti M, Schenone S, Bandiera T, Carbone A, Massari S. Small Molecules Targeting DNA Polymerase Theta (POLθ) as Promising Synthetic Lethal Agents for Precision Cancer Therapy. J Med Chem 2023; 66:6498-6522. [PMID: 37134182 DOI: 10.1021/acs.jmedchem.2c02101] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Synthetic lethality (SL) is an innovative strategy in targeted anticancer therapy that exploits tumor genetic vulnerabilities. This topic has come to the forefront in recent years, as witnessed by the increased number of publications since 2007. The first proof of concept for the effectiveness of SL was provided by the approval of poly(ADP-ribose)polymerase inhibitors, which exploit a SL interaction in BRCA-deficient cells, although their use is limited by resistance. Searching for additional SL interactions involving BRCA mutations, the DNA polymerase theta (POLθ) emerged as an exciting target. This review summarizes, for the first time, the POLθ polymerase and helicase inhibitors reported to date. Compounds are described focusing on chemical structure and biological activity. With the aim to enable further drug discovery efforts in interrogating POLθ as a target, we propose a plausible pharmacophore model for POLθ-pol inhibitors and provide a structural analysis of the known POLθ ligand binding sites.
Collapse
Affiliation(s)
- Maria Chiara Pismataro
- Department of Pharmaceutical Sciences, University of Perugia, Via del Liceo 1, 06123 Perugia, Italy
| | - Andrea Astolfi
- Department of Pharmaceutical Sciences, University of Perugia, Via del Liceo 1, 06123 Perugia, Italy
| | - Maria Letizia Barreca
- Department of Pharmaceutical Sciences, University of Perugia, Via del Liceo 1, 06123 Perugia, Italy
| | - Martina Pacetti
- Department of Pharmaceutical Sciences, University of Perugia, Via del Liceo 1, 06123 Perugia, Italy
| | - Silvia Schenone
- Department of Pharmacy, University of Genoa, Viale Benedetto XV 3, 16132 Genoa, Italy
| | - Tiziano Bandiera
- D3 PharmaChemistry, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Anna Carbone
- Department of Pharmacy, University of Genoa, Viale Benedetto XV 3, 16132 Genoa, Italy
| | - Serena Massari
- Department of Pharmaceutical Sciences, University of Perugia, Via del Liceo 1, 06123 Perugia, Italy
| |
Collapse
|
14
|
Rogers CB, Kram RE, Lin K, Myers CL, Sobeck A, Hendrickson EA, Bielinsky AK. Fanconi anemia-associated chromosomal radial formation is dependent on POLθ-mediated alternative end joining. Cell Rep 2023; 42:112428. [PMID: 37086407 DOI: 10.1016/j.celrep.2023.112428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 01/25/2023] [Accepted: 04/07/2023] [Indexed: 04/23/2023] Open
Abstract
Activation of the Fanconi anemia (FA) pathway after treatment with mitomycin C (MMC) is essential for preventing chromosome translocations termed "radials." When replication forks stall at MMC-induced interstrand crosslinks (ICLs), the FA pathway is activated to orchestrate ICL unhooking and repair of the DNA break intermediates. However, in FA-deficient cells, how ICL-associated breaks are resolved in a manner that leads to radials is unclear. Here, we demonstrate that MMC-induced radials are dependent on DNA polymerase theta (POLθ)-mediated alternative end joining (A-EJ). Specifically, we show that radials observed in FANCD2-/- cells are dependent on POLθ and DNA ligase III and occur independently of classical non-homologous end joining. Furthermore, treatment of FANCD2-/- cells with POLθ inhibitors abolishes radials and leads to the accumulation of breaks co-localizing with common fragile sites. Uniformly, these observations implicate A-EJ in radial formation and provide mechanistic insights into the treatment of FA pathway-deficient cancers with POLθ inhibitors.
Collapse
Affiliation(s)
- Colette B Rogers
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Rachel E Kram
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Kevin Lin
- Department of Computer Science and Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | - Chad L Myers
- Department of Computer Science and Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | - Alexandra Sobeck
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Eric A Hendrickson
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA.
| | - Anja-Katrin Bielinsky
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA.
| |
Collapse
|
15
|
Yi G, Sung Y, Kim C, Ra JS, Hirakawa H, Kato T, Fujimori A, Kim H, Takata KI. DNA polymerase θ-mediated repair of high LET radiation-induced complex DNA double-strand breaks. Nucleic Acids Res 2023; 51:2257-2269. [PMID: 36805268 PMCID: PMC10018357 DOI: 10.1093/nar/gkad076] [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: 07/19/2022] [Revised: 01/21/2023] [Accepted: 01/25/2023] [Indexed: 02/22/2023] Open
Abstract
DNA polymerase θ (POLQ) is a unique DNA polymerase that is able to perform microhomology-mediated end-joining as well as translesion synthesis (TLS) across an abasic (AP) site and thymine glycol (Tg). However, the biological significance of the TLS activity is currently unknown. Herein we provide evidence that the TLS activity of POLQ plays a critical role in repairing complex DNA double-strand breaks (DSBs) induced by high linear energy transfer (LET) radiation. Radiotherapy with high LET radiation such as carbon ions leads to more deleterious biological effects than corresponding doses of low LET radiation such as X-rays. High LET-induced DSBs are considered to be complex, carrying additional DNA damage such as AP site and Tg in close proximity to the DSB sites. However, it is not clearly understood how complex DSBs are processed in mammalian cells. We demonstrated that genetic disruption of POLQ results in an increase of chromatid breaks and enhanced cellular sensitivity following treatment with high LET radiation. At the biochemical level, POLQ was able to bypass an AP site and Tg during end-joining and was able to anneal two single-stranded DNA tails when DNA lesions were located outside the microhomology. This study offers evidence that POLQ is directly involved in the repair of complex DSBs.
Collapse
Affiliation(s)
- Geunil Yi
- Center for Genomic Integrity, Institute for Basic Science, Ulsan 44919, Republic of Korea
- Department of Biological Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Yubin Sung
- Center for Genomic Integrity, Institute for Basic Science, Ulsan 44919, Republic of Korea
| | - Chanwoo Kim
- Department of Biomedical Engineering, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Jae Sun Ra
- Center for Genomic Integrity, Institute for Basic Science, Ulsan 44919, Republic of Korea
| | - Hirokazu Hirakawa
- Department of Charged Particle Therapy Research, Institute for Quantum Medical Science, Chiba 263-8555, Japan
| | - Takamitsu A Kato
- Department of Environmental & Radiological Health Sciences, Colorado State University, Colorado 80523, USA
| | - Akira Fujimori
- Department of Charged Particle Therapy Research, Institute for Quantum Medical Science, Chiba 263-8555, Japan
| | - Hajin Kim
- Center for Genomic Integrity, Institute for Basic Science, Ulsan 44919, Republic of Korea
- Department of Biomedical Engineering, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Kei-ichi Takata
- Center for Genomic Integrity, Institute for Basic Science, Ulsan 44919, Republic of Korea
- Department of Biological Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| |
Collapse
|
16
|
Multifaceted Nature of DNA Polymerase θ. Int J Mol Sci 2023; 24:ijms24043619. [PMID: 36835031 PMCID: PMC9962433 DOI: 10.3390/ijms24043619] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Revised: 01/26/2023] [Accepted: 02/02/2023] [Indexed: 02/15/2023] Open
Abstract
DNA polymerase θ belongs to the A family of DNA polymerases and plays a key role in DNA repair and damage tolerance, including double-strand break repair and DNA translesion synthesis. Pol θ is often overexpressed in cancer cells and promotes their resistance to chemotherapeutic agents. In this review, we discuss unique biochemical properties and structural features of Pol θ, its multiple roles in protection of genome stability and the potential of Pol θ as a target for cancer treatment.
Collapse
|
17
|
Li C, Zhu H, Jin S, Maksoud LM, Jain N, Sun J, Gao Y. Structural basis of DNA polymerase θ mediated DNA end joining. Nucleic Acids Res 2023; 51:463-474. [PMID: 36583344 PMCID: PMC9841435 DOI: 10.1093/nar/gkac1201] [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: 09/22/2022] [Revised: 11/30/2022] [Accepted: 12/05/2022] [Indexed: 12/31/2022] Open
Abstract
DNA polymerase θ (Pol θ) plays an essential role in the microhomology-mediated end joining (MMEJ) pathway for repairing DNA double-strand breaks. However, the mechanisms by which Pol θ recognizes microhomologous DNA ends and performs low-fidelity DNA synthesis remain unclear. Here, we present cryo-electron microscope structures of the polymerase domain of Lates calcarifer Pol θ with long and short duplex DNA at up to 2.4 Å resolution. Interestingly, Pol θ binds to long and short DNA substrates similarly, with extensive interactions around the active site. Moreover, Pol θ shares a similar active site as high-fidelity A-family polymerases with its finger domain well-closed but differs in having hydrophilic residues surrounding the nascent base pair. Computational simulations and mutagenesis studies suggest that the unique insertion loops of Pol θ help to stabilize short DNA binding and assemble the active site for MMEJ repair. Taken together, our results illustrate the structural basis of Pol θ-mediated MMEJ.
Collapse
Affiliation(s)
- Chuxuan Li
- Department of Biosciences, Rice University, Houston, TX 77005, USA
| | - Hanwen Zhu
- Department of Structural Biology, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA
| | - Shikai Jin
- Department of Biosciences, Rice University, Houston, TX 77005, USA
- Center for Theoretical Biological Physics, Rice University, Houston, TX 77005, USA
| | - Leora M Maksoud
- Department of Biosciences, Rice University, Houston, TX 77005, USA
| | - Nikhil Jain
- Department of Structural Biology, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA
| | - Ji Sun
- Department of Structural Biology, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA
| | - Yang Gao
- Department of Biosciences, Rice University, Houston, TX 77005, USA
| |
Collapse
|
18
|
Patterson-Fortin J, D'Andrea AD. Targeting Polymerase Theta (POLθ) for Cancer Therapy. Cancer Treat Res 2023; 186:285-298. [PMID: 37978141 DOI: 10.1007/978-3-031-30065-3_15] [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] [Indexed: 11/19/2023]
Abstract
Polymerase theta (POLθ) is the critical multi-domain enzyme in microhomology-mediated end-joining DNA double-stranded break repair. POLθ is expressed at low levels in normal tissue but is often overexpressed in cancers, especially in DNA repair deficient cancers, such as homologous-recombination cancers, rendering them exquisitely sensitive to POLθ inhibition secondary to synthetic lethality. Development of POLθ inhibitors is an active area of investigation with inhibitors of the N-terminal helicase domain or the C-terminal polymerase domain currently in clinical trial. Here, we review POLθ-mediated microhomology-mediated end-joining, the development of POLθ inhibitors, and the potential clinical uses of POLθ inhibitors.
Collapse
Affiliation(s)
- Jeffrey Patterson-Fortin
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, 02215, USA
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Boston, MA, 02215, USA
| | - Alan D D'Andrea
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Boston, MA, 02215, USA.
- Harvard Medical School, Center for DNA Damage and Repair, Susan F. Smith Center for Women's Cancers (SFSCWC), The Fuller-American Cancer Society, Dana-Farber Cancer Institute, HIM 243, 450 Brookline Ave., Boston, MA, 02215, USA.
| |
Collapse
|
19
|
Abstract
DNA polymerase θ (Pol θ) is a DNA repair enzyme widely conserved in animals and plants. Pol θ uses short DNA sequence homologies to initiate repair of double-strand breaks by theta-mediated end joining. The DNA polymerase domain of Pol θ is at the C terminus and is connected to an N-terminal DNA helicase-like domain by a central linker. Pol θ is crucial for maintenance of damaged genomes during development, protects DNA against extensive deletions, and limits loss of heterozygosity. The cost of using Pol θ for genome protection is that a few nucleotides are usually deleted or added at the repair site. Inactivation of Pol θ often enhances the sensitivity of cells to DNA strand-breaking chemicals and radiation. Since some homologous recombination-defective cancers depend on Pol θ for growth, inhibitors of Pol θ may be useful in treating such tumors.
Collapse
Affiliation(s)
- Richard D Wood
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Center, Houston, Texas, USA;
| | - Sylvie Doublié
- Department of Microbiology and Molecular Genetics, University of Vermont, Burlington, Vermont, USA;
| |
Collapse
|
20
|
Wilson J, Loizou JI. Exploring the genetic space of the DNA damage response for cancer therapy through CRISPR-based screens. Mol Oncol 2022; 16:3778-3791. [PMID: 35708734 PMCID: PMC9627789 DOI: 10.1002/1878-0261.13272] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 05/11/2022] [Accepted: 06/14/2022] [Indexed: 12/24/2022] Open
Abstract
The concepts of synthetic lethality and viability have emerged as powerful approaches to identify vulnerabilities and resistances within the DNA damage response for the treatment of cancer. Historically, interactions between two genes have had a longstanding presence in genetics and have been identified through forward genetic screens that rely on the molecular basis of the characterized phenotypes, typically caused by mutations in single genes. While such complex genetic interactions between genes have been studied extensively in model organisms, they have only recently been prioritized as therapeutic strategies due to technological advancements in genetic screens. Here, we discuss synthetic lethal and viable interactions within the DNA damage response and present how CRISPR-based genetic screens and chemical compounds have allowed for the systematic identification and targeting of such interactions for the treatment of cancer.
Collapse
Affiliation(s)
- Jordan Wilson
- Center for Cancer Research, Comprehensive Cancer CentreMedical University of ViennaAustria
- CeMM Research Center for Molecular Medicine of the Austrian Academy of SciencesViennaAustria
| | - Joanna I. Loizou
- Center for Cancer Research, Comprehensive Cancer CentreMedical University of ViennaAustria
- CeMM Research Center for Molecular Medicine of the Austrian Academy of SciencesViennaAustria
| |
Collapse
|
21
|
Stockley ML, Ferdinand A, Benedetti G, Blencowe P, Boyd SM, Calder M, Charles MD, Edwardes LV, Ekwuru T, Finch H, Galbiati A, Geo L, Grande D, Grinkevich V, Holliday ND, Krajewski WW, MacDonald E, Majithiya JB, McCarron H, McWhirter CL, Patel V, Pedder C, Rajendra E, Ranzani M, Rigoreau LJM, Robinson HMR, Schaedler T, Sirina J, Smith GCM, Swarbrick ME, Turnbull AP, Willis S, Heald RA. Discovery, Characterization, and Structure-Based Optimization of Small-Molecule In Vitro and In Vivo Probes for Human DNA Polymerase Theta. J Med Chem 2022; 65:13879-13891. [PMID: 36200480 DOI: 10.1021/acs.jmedchem.2c01142] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Human DNA polymerase theta (Polθ), which is essential for microhomology-mediated DNA double strand break repair, has been proposed as an attractive target for the treatment of BRCA deficient and other DNA repair pathway defective cancers. As previously reported, we recently identified the first selective small molecule Polθ in vitro probe, 22 (ART558), which recapitulates the phenotype of Polθ loss, and in vivo probe, 43 (ART812), which is efficacious in a model of PARP inhibitor resistant TNBC in vivo. Here we describe the discovery, biochemical and biophysical characterization of these probes including small molecule ligand co-crystal structures with Polθ. The crystallographic data provides a basis for understanding the unique mechanism of inhibition of these compounds which is dependent on stabilization of a "closed" enzyme conformation. Additionally, the structural biology platform provided a basis for rational optimization based primarily on reduced ligand conformational flexibility.
Collapse
Affiliation(s)
- Martin L Stockley
- Artios Pharma Ltd., B940, Babraham Research Campus, CambridgeCB22 3FH, U. K
| | - Amanda Ferdinand
- Cancer Research Horizons Therapeutic Innovation, Jonas Webb Building, Babraham Research Campus, CambridgeCB22 3AT, U. K
| | - Giovanni Benedetti
- Artios Pharma Ltd., B940, Babraham Research Campus, CambridgeCB22 3FH, U. K
| | - Peter Blencowe
- Cancer Research Horizons Therapeutic Innovation, Jonas Webb Building, Babraham Research Campus, CambridgeCB22 3AT, U. K
| | - Susan M Boyd
- CompChem Solutions Ltd, St John's Innovation Centre, Cowley Rd, CambridgeCB4 0WS, U. K
| | - Mat Calder
- Cancer Research Horizons Therapeutic Innovation, Jonas Webb Building, Babraham Research Campus, CambridgeCB22 3AT, U. K
| | - Mark D Charles
- Cancer Research Horizons Therapeutic Innovation, Jonas Webb Building, Babraham Research Campus, CambridgeCB22 3AT, U. K
| | - Lucy V Edwardes
- Artios Pharma Ltd., B940, Babraham Research Campus, CambridgeCB22 3FH, U. K
| | - Tennyson Ekwuru
- Cancer Research Horizons Therapeutic Innovation, Jonas Webb Building, Babraham Research Campus, CambridgeCB22 3AT, U. K
| | - Harry Finch
- Artios Pharma Ltd., B940, Babraham Research Campus, CambridgeCB22 3FH, U. K
| | | | - Lerin Geo
- Artios Pharma Ltd., B940, Babraham Research Campus, CambridgeCB22 3FH, U. K
| | - Diego Grande
- Artios Pharma Ltd., B940, Babraham Research Campus, CambridgeCB22 3FH, U. K
| | - Vera Grinkevich
- Artios Pharma Ltd., B940, Babraham Research Campus, CambridgeCB22 3FH, U. K
| | - Nicholas D Holliday
- Excellerate Bioscience Ltd., BioCity, Pennyfoot Street, NottinghamNG1 1GF, U. K
| | - Wojciech W Krajewski
- Cancer Research Horizons Therapeutic Innovation, The Francis Crick Institute, 1 Midland Road, LondonNW1 1AT, U. K
| | - Ellen MacDonald
- Cancer Research Horizons Therapeutic Innovation, Jonas Webb Building, Babraham Research Campus, CambridgeCB22 3AT, U. K
| | - Jayesh B Majithiya
- Artios Pharma Ltd., B940, Babraham Research Campus, CambridgeCB22 3FH, U. K
| | - Hollie McCarron
- Cancer Research Horizons Therapeutic Innovation, Jonas Webb Building, Babraham Research Campus, CambridgeCB22 3AT, U. K
| | - Claire L McWhirter
- Artios Pharma Ltd., B940, Babraham Research Campus, CambridgeCB22 3FH, U. K
| | - Viral Patel
- Excellerate Bioscience Ltd., BioCity, Pennyfoot Street, NottinghamNG1 1GF, U. K
| | - Chris Pedder
- Cancer Research Horizons Therapeutic Innovation, Jonas Webb Building, Babraham Research Campus, CambridgeCB22 3AT, U. K
| | - Eeson Rajendra
- Artios Pharma Ltd., B940, Babraham Research Campus, CambridgeCB22 3FH, U. K
| | - Marco Ranzani
- Artios Pharma Ltd., B940, Babraham Research Campus, CambridgeCB22 3FH, U. K
| | - Laurent J M Rigoreau
- Cancer Research Horizons Therapeutic Innovation, Jonas Webb Building, Babraham Research Campus, CambridgeCB22 3AT, U. K
| | - Helen M R Robinson
- Artios Pharma Ltd., B940, Babraham Research Campus, CambridgeCB22 3FH, U. K
| | - Theresia Schaedler
- Artios Pharma Ltd., B940, Babraham Research Campus, CambridgeCB22 3FH, U. K
| | - Julija Sirina
- Excellerate Bioscience Ltd., BioCity, Pennyfoot Street, NottinghamNG1 1GF, U. K
| | - Graeme C M Smith
- Artios Pharma Ltd., B940, Babraham Research Campus, CambridgeCB22 3FH, U. K
| | - Martin E Swarbrick
- Cancer Research Horizons Therapeutic Innovation, Jonas Webb Building, Babraham Research Campus, CambridgeCB22 3AT, U. K
| | - Andrew P Turnbull
- Cancer Research Horizons Therapeutic Innovation, The Francis Crick Institute, 1 Midland Road, LondonNW1 1AT, U. K
| | - Simon Willis
- Cancer Research Horizons Therapeutic Innovation, The Francis Crick Institute, 1 Midland Road, LondonNW1 1AT, U. K
| | - Robert A Heald
- Artios Pharma Ltd., B940, Babraham Research Campus, CambridgeCB22 3FH, U. K
| |
Collapse
|
22
|
Vanson S, Li Y, Wood RD, Doublié S. Probing the structure and function of polymerase θ helicase-like domain. DNA Repair (Amst) 2022; 116:103358. [PMID: 35753097 PMCID: PMC10329254 DOI: 10.1016/j.dnarep.2022.103358] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 06/09/2022] [Accepted: 06/09/2022] [Indexed: 11/19/2022]
Abstract
DNA Polymerase θ is the key actuator of the recently identified double-strand break repair pathway, theta-mediated end joining (TMEJ). It is the only known polymerase to have a 3-domain architecture containing an independently functional family A DNA polymerase tethered by a long central region to an N-terminal helicase-like domain (HLD). Full-length polymerase θ and the isolated HLD hydrolyze ATP in the presence of DNA, but no processive DNA duplex unwinding has been observed. Based on sequence and structure conservation, the HLD is classified as a member of helicase superfamily II and, more specifically, the Ski2-like family. The specific subdomain composition and organization most closely resemble that of archaeal DNA repair helicases Hel308 and Hjm. The underlying structural basis as to why the HLD is not able to processively unwind duplex DNA, despite its similarity to bona fide helicases, remains elusive. Activities of the HLD include ATP hydrolysis, protein displacement, and annealing of complementary DNA. These observations have led to speculation about the role of the HLD within the context of double-strand break repair via TMEJ, such as removal of single-stranded DNA binding proteins like RPA and RAD51 and microhomology alignment. This review summarizes the structural classification and organization of the polymerase θ HLD and its homologs and explores emerging data on its biochemical activities. We conclude with a simple, speculative model for the HLD's role in TMEJ.
Collapse
Affiliation(s)
- Scott Vanson
- Department of Microbiology and Molecular Genetics, University of Vermont, 89 Beaumont Ave, Burlington, VT 05405, USA
| | - Yuzhen Li
- Department of Epigenetics & Molecular Carcinogenesis, The University of Texas MD Anderson Center, Houston, TX 77230, USA
| | - Richard D Wood
- Department of Epigenetics & Molecular Carcinogenesis, The University of Texas MD Anderson Center, Houston, TX 77230, USA.
| | - Sylvie Doublié
- Department of Microbiology and Molecular Genetics, University of Vermont, 89 Beaumont Ave, Burlington, VT 05405, USA.
| |
Collapse
|
23
|
Moyret-Lalle C, Prodhomme MK, Burlet D, Kashiwagi A, Petrilli V, Puisieux A, Seimiya H, Tissier A. Role of EMT in the DNA damage response, double-strand break repair pathway choice and its implications in cancer treatment. Cancer Sci 2022; 113:2214-2223. [PMID: 35534984 PMCID: PMC9277259 DOI: 10.1111/cas.15389] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 04/20/2022] [Accepted: 04/25/2022] [Indexed: 11/30/2022] Open
Abstract
Numerous epithelial–mesenchymal transition (EMT) characteristics have now been demonstrated to participate in tumor development. Indeed, EMT is involved in invasion, acquisition of stem cell properties, and therapy‐associated resistance of cancer cells. Together, these mechanisms offer advantages in adapting to changes in the tumor microenvironment. However, recent findings have shown that EMT‐associated transcription factors (EMT‐TFs) may also be involved in DNA repair. A better understanding of the coordination between the DNA repair pathways and the role played by some EMT‐TFs in the DNA damage response (DDR) should pave the way for new treatments targeting tumor‐specific molecular vulnerabilities, which result in selective destruction of cancer cells. Here we review recent advances, providing novel insights into the role of EMT in the DDR and repair pathways, with a particular focus on the influence of EMT on cellular sensitivity to damage, as well as the implications of these relationships for improving the efficacy of cancer treatments.
Collapse
Affiliation(s)
- Caroline Moyret-Lalle
- Université de Lyon, Université Claude Bernard Lyon 1, INSERM 1052, CNRS 5286, Centre Léon Bérard, Cancer Research Centre of Lyon, Lyon, France.,LabEx DEVweCAN, Université de Lyon, Lyon, France
| | - Mélanie K Prodhomme
- Department of Epigenetics & Molecular Carcinogenesis, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Delphine Burlet
- Université de Lyon, Université Claude Bernard Lyon 1, INSERM 1052, CNRS 5286, Centre Léon Bérard, Cancer Research Centre of Lyon, Lyon, France
| | - Ayaka Kashiwagi
- Division of Molecular Biotherapy, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, Tokyo, Japan.,Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Tokyo, Japan
| | - Virginie Petrilli
- Université de Lyon, Université Claude Bernard Lyon 1, INSERM 1052, CNRS 5286, Centre Léon Bérard, Cancer Research Centre of Lyon, Lyon, France
| | - Alain Puisieux
- Institut Curie, Versailles Saint-Quentin-en-Yvelines University, PSL Research University, Paris, France
| | - Hiroyuki Seimiya
- Division of Molecular Biotherapy, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, Tokyo, Japan.,Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Tokyo, Japan
| | - Agnès Tissier
- Université de Lyon, Université Claude Bernard Lyon 1, INSERM 1052, CNRS 5286, Centre Léon Bérard, Cancer Research Centre of Lyon, Lyon, France
| |
Collapse
|
24
|
Carvalho G, Repolês BM, Mendes I, Wanrooij PH. Mitochondrial DNA Instability in Mammalian Cells. Antioxid Redox Signal 2022; 36:885-905. [PMID: 34015960 PMCID: PMC9127837 DOI: 10.1089/ars.2021.0091] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 05/11/2021] [Indexed: 02/06/2023]
Abstract
Significance: The small, multicopy mitochondrial genome (mitochondrial DNA [mtDNA]) is essential for efficient energy production, as alterations in its coding information or a decrease in its copy number disrupt mitochondrial ATP synthesis. However, the mitochondrial replication machinery encounters numerous challenges that may limit its ability to duplicate this important genome and that jeopardize mtDNA stability, including various lesions in the DNA template, topological stress, and an insufficient nucleotide supply. Recent Advances: An ever-growing array of DNA repair or maintenance factors are being reported to localize to the mitochondria. We review current knowledge regarding the mitochondrial factors that may contribute to the tolerance or repair of various types of changes in the mitochondrial genome, such as base damage, incorporated ribonucleotides, and strand breaks. We also discuss the newly discovered link between mtDNA instability and activation of the innate immune response. Critical Issues: By which mechanisms do mitochondria respond to challenges that threaten mtDNA maintenance? What types of mtDNA damage are repaired, and when are the affected molecules degraded instead? And, finally, which forms of mtDNA instability trigger an immune response, and how? Future Directions: Further work is required to understand the contribution of the DNA repair and damage-tolerance factors present in the mitochondrial compartment, as well as the balance between mtDNA repair and degradation. Finally, efforts to understand the events underlying mtDNA release into the cytosol are warranted. Pursuing these and many related avenues can improve our understanding of what goes wrong in mitochondrial disease. Antioxid. Redox Signal. 36, 885-905.
Collapse
Affiliation(s)
- Gustavo Carvalho
- Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden
| | - Bruno Marçal Repolês
- Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden
| | - Isabela Mendes
- Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden
| | - Paulina H. Wanrooij
- Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden
| |
Collapse
|
25
|
Schaub JM, Soniat MM, Finkelstein IJ. Polymerase theta-helicase promotes end joining by stripping single-stranded DNA-binding proteins and bridging DNA ends. Nucleic Acids Res 2022; 50:3911-3921. [PMID: 35357490 PMCID: PMC9023281 DOI: 10.1093/nar/gkac119] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 01/20/2022] [Accepted: 03/29/2022] [Indexed: 01/20/2023] Open
Abstract
Homologous recombination-deficient cancers rely on DNA polymerase Theta (Polθ)-Mediated End Joining (TMEJ), an alternative double-strand break repair pathway. Polθ is the only vertebrate polymerase that encodes an N-terminal superfamily 2 (SF2) helicase domain, but the role of this helicase domain in TMEJ remains unclear. Using single-molecule imaging, we demonstrate that Polθ-helicase (Polθ-h) is a highly processive single-stranded DNA (ssDNA) motor protein that can efficiently strip Replication Protein A (RPA) from ssDNA. Polθ-h also has a limited capacity for disassembling RAD51 filaments but is not processive on double-stranded DNA. Polθ-h can bridge two non-complementary DNA strands in trans. PARylation of Polθ-h by PARP-1 resolves these DNA bridges. We conclude that Polθ-h removes RPA and RAD51 filaments and mediates bridging of DNA overhangs to aid in polymerization by the Polθ polymerase domain.
Collapse
Affiliation(s)
- Jeffrey M Schaub
- Department of Molecular Biosciences and Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX 78712, USA
| | - Michael M Soniat
- Department of Molecular Biosciences and Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX 78712, USA
| | - Ilya J Finkelstein
- Department of Molecular Biosciences and Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX 78712, USA.,Center for Systems and Synthetic Biology, The University of Texas at Austin, Austin, TX 78712, USA
| |
Collapse
|
26
|
Ramsden DA, Carvajal-Garcia J, Gupta GP. Mechanism, cellular functions and cancer roles of polymerase-theta-mediated DNA end joining. Nat Rev Mol Cell Biol 2022; 23:125-140. [PMID: 34522048 DOI: 10.1038/s41580-021-00405-2] [Citation(s) in RCA: 87] [Impact Index Per Article: 43.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/21/2021] [Indexed: 02/08/2023]
Abstract
Cellular pathways that repair chromosomal double-strand breaks (DSBs) have pivotal roles in cell growth, development and cancer. These DSB repair pathways have been the target of intensive investigation, but one pathway - alternative end joining (a-EJ) - has long resisted elucidation. In this Review, we highlight recent progress in our understanding of a-EJ, especially the assignment of DNA polymerase theta (Polθ) as the predominant mediator of a-EJ in most eukaryotes, and discuss a potential molecular mechanism by which Polθ-mediated end joining (TMEJ) occurs. We address possible cellular functions of TMEJ in resolving DSBs that are refractory to repair by non-homologous end joining (NHEJ), DSBs generated following replication fork collapse and DSBs present owing to stalling of repair by homologous recombination. We also discuss how these context-dependent cellular roles explain how TMEJ can both protect against and cause genome instability, and the emerging potential of Polθ as a therapeutic target in cancer.
Collapse
Affiliation(s)
- Dale A Ramsden
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
| | - Juan Carvajal-Garcia
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Gaorav P Gupta
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
- Department of Radiation Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
| |
Collapse
|
27
|
Feng W, Smith CM, Simpson DA, Gupta GP. Targeting Non-homologous and Alternative End Joining Repair to Enhance Cancer Radiosensitivity. Semin Radiat Oncol 2021; 32:29-41. [PMID: 34861993 DOI: 10.1016/j.semradonc.2021.09.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Many cancer therapies, including radiotherapy, induce DSBs as the major driving mechanism for inducing cancer cell death. Thus, modulating DSB repair has immense potential for radiosensitization, although such interventions must be carefully designed to be tumor selective to ensure that normal tissue toxicities are not also increased. Here, we review mechanisms of error-prone DSB repair through a highly efficient process called end joining. There are two major pathways of end-joining repair: non-homologous end joining (NHEJ) and alternative end joining (a-EJ), both of which can be selectively upregulated in cancer and thus represent attractive therapeutic targets for radiosensitization. These EJ pathways each have therapeutically targetable pioneer factors - DNA-dependent protein kinase catalytic subunit (DNA-PKcs) for NHEJ and DNA Polymerase Theta (Pol θ) for a-EJ. We summarize the current status of therapeutic targeting of NHEJ and a-EJ to enhance the effects of radiotherapy - focusing on challenges that must be overcome and opportunities that require further exploration. By leveraging preclinical insights into mechanisms of altered DSB repair programs in cancer, selective radiosensitization through NHEJ and/or a-EJ targeting remains a highly attractive avenue for ongoing and future clinical investigation.
Collapse
Affiliation(s)
| | - Chelsea M Smith
- Lineberger Comprehensive Cancer Center; Pathobiology and Translational Science Graduate Program
| | | | - Gaorav P Gupta
- Lineberger Comprehensive Cancer Center; Pathobiology and Translational Science Graduate Program; Department of Radiation Oncology; Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, NC.
| |
Collapse
|
28
|
Russi M, Marson D, Fermeglia A, Aulic S, Fermeglia M, Laurini E, Pricl S. The fellowship of the RING: BRCA1, its partner BARD1 and their liaison in DNA repair and cancer. Pharmacol Ther 2021; 232:108009. [PMID: 34619284 DOI: 10.1016/j.pharmthera.2021.108009] [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: 08/14/2021] [Revised: 08/22/2021] [Accepted: 09/20/2021] [Indexed: 12/12/2022]
Abstract
The breast cancer type 1 susceptibility protein (BRCA1) and its partner - the BRCA1-associated RING domain protein 1 (BARD1) - are key players in a plethora of fundamental biological functions including, among others, DNA repair, replication fork protection, cell cycle progression, telomere maintenance, chromatin remodeling, apoptosis and tumor suppression. However, mutations in their encoding genes transform them into dangerous threats, and substantially increase the risk of developing cancer and other malignancies during the lifetime of the affected individuals. Understanding how BRCA1 and BARD1 perform their biological activities therefore not only provides a powerful mean to prevent such fatal occurrences but can also pave the way to the development of new targeted therapeutics. Thus, through this review work we aim at presenting the major efforts focused on the functional characterization and structural insights of BRCA1 and BARD1, per se and in combination with all their principal mediators and regulators, and on the multifaceted roles these proteins play in the maintenance of human genome integrity.
Collapse
Affiliation(s)
- Maria Russi
- Molecular Biology and Nanotechnology Laboratory (MolBNL@UniTs), DEA, University of Trieste, Trieste, Italy
| | - Domenico Marson
- Molecular Biology and Nanotechnology Laboratory (MolBNL@UniTs), DEA, University of Trieste, Trieste, Italy
| | - Alice Fermeglia
- Molecular Biology and Nanotechnology Laboratory (MolBNL@UniTs), DEA, University of Trieste, Trieste, Italy
| | - Suzana Aulic
- Molecular Biology and Nanotechnology Laboratory (MolBNL@UniTs), DEA, University of Trieste, Trieste, Italy
| | - Maurizio Fermeglia
- Molecular Biology and Nanotechnology Laboratory (MolBNL@UniTs), DEA, University of Trieste, Trieste, Italy
| | - Erik Laurini
- Molecular Biology and Nanotechnology Laboratory (MolBNL@UniTs), DEA, University of Trieste, Trieste, Italy
| | - Sabrina Pricl
- Molecular Biology and Nanotechnology Laboratory (MolBNL@UniTs), DEA, University of Trieste, Trieste, Italy; Department of General Biophysics, Faculty of Biology and Environmental Protection, University of Lodz, Lodz, Poland.
| |
Collapse
|
29
|
Zahn KE, Jensen RB. Polymerase θ Coordinates Multiple Intrinsic Enzymatic Activities during DNA Repair. Genes (Basel) 2021; 12:1310. [PMID: 34573292 PMCID: PMC8470613 DOI: 10.3390/genes12091310] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 08/19/2021] [Accepted: 08/20/2021] [Indexed: 11/16/2022] Open
Abstract
The POLQ gene encodes DNA polymerase θ, a 2590 amino acid protein product harboring DNA-dependent ATPase, template-dependent DNA polymerase, dNTP-dependent endonuclease, and 5'-dRP lyase functions. Polymerase θ participates at an essential step of a DNA double-strand break repair pathway able to join 5'-resected substrates by locating and pairing microhomologies present in 3'-overhanging single-stranded tails, cleaving the extraneous 3'-DNA by dNTP-dependent end-processing, before extending the nascent 3' end from the microhomology annealing site. Metazoans require polymerase θ for full resistance to DNA double-strand break inducing agents but can survive knockout of the POLQ gene. Cancer cells with compromised homologous recombination, or other DNA repair defects, over-utilize end-joining by polymerase θ and often over-express the POLQ gene. This dependency points to polymerase θ as an ideal drug target candidate and multiple drug-development programs are now preparing to enter clinical trials with small-molecule inhibitors. Specific inhibitors of polymerase θ would not only be predicted to treat BRCA-mutant cancers, but could thwart accumulated resistance to current standard-of-care cancer therapies and overcome PARP-inhibitor resistance in patients. This article will discuss synthetic lethal strategies targeting polymerase θ in DNA damage-response-deficient cancers and summarize data, describing molecular structures and enzymatic functions.
Collapse
Affiliation(s)
- Karl E. Zahn
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06520, USA
- Repare Therapeutics, 7210 Rue Frederick Banting, Montreal, QC H4S 2A1, Canada
| | - Ryan B. Jensen
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06520, USA
| |
Collapse
|
30
|
Mouse papillomavirus type 1 (MmuPV1) DNA is frequently integrated in benign tumors by microhomology-mediated end-joining. PLoS Pathog 2021; 17:e1009812. [PMID: 34343212 PMCID: PMC8362953 DOI: 10.1371/journal.ppat.1009812] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 08/13/2021] [Accepted: 07/19/2021] [Indexed: 12/24/2022] Open
Abstract
MmuPV1 is a useful model for studying papillomavirus-induced tumorigenesis. We used RNA-seq to look for chimeric RNAs that map to both MmuPV1 and host genomes. In tumor tissues, a higher proportion of total viral reads were virus-host chimeric junction reads (CJRs) (1.9‰ - 7‰) than in tumor-free tissues (0.6‰ - 1.3‰): most CJRs mapped to the viral E2/E4 region. Although most of the MmuPV1 integration sites were mapped to intergenic regions and introns throughout the mouse genome, integrations were seen more than once in several genes: Malat1, Krt1, Krt10, Fabp5, Pard3, and Grip1; these data were confirmed by rapid amplification of cDNA ends (RACE)-Single Molecule Real-Time (SMRT)-seq or targeted DNA-seq. Microhomology sequences were frequently seen at host-virus DNA junctions. MmuPV1 infection and integration affected the expression of host genes. We found that factors for DNA double-stranded break repair and microhomology-mediated end-joining (MMEJ), such as H2ax, Fen1, DNA polymerase Polθ, Cdk1, and Plk1, exhibited a step-wise increase and Mdc1 a decrease in expression in MmuPV1-infected tissues and MmuPV1 tumors relative to normal tissues. Increased expression of mitotic kinases CDK1 and PLK1 appears to be correlated with CtIP phosphorylation in MmuPV1 tumors, suggesting a role for MMEJ-mediated DNA joining in the MmuPV1 integration events that are associated with MmuPV1-induced progression of tumors. Persistent high-risk HPV infection leads viral DNA integration into the host genome and promotes viral carcinogenesis. We have been using the MmuPV1 mouse-infection model to study papillomavirus tumorigenesis and asked whether MmuPV1 DNA also integrates into the genomes of infected mouse cells. Strikingly, we found that MmuPV1 integration into the infected host genome, like high-risk HPV infections, is very common and the mapped integration sites were distributed on all of the mouse chromosomes. Consistently, we identified microhomology sequences in the range of 2–10 nts always at the integration junction regions. We further verified the MMEJ-mediated viral DNA integration in tumor tissues during MmuPV1 infection and a step-wise increase in the expression of the DNA repair MMEJ host factors from normal tissues, to tumor-free MmuPV1 infected tissues, and then to MmuPV1 tumors. Our observations provide the first evidence of MmuPV1 integration in virus-infected cells and a conceptual advance of how papillomavirus DNA integration contributes to the development of papillomavirus-associated precancers to cancers.
Collapse
|
31
|
Chen XS, Pomerantz RT. DNA Polymerase θ: A Cancer Drug Target with Reverse Transcriptase Activity. Genes (Basel) 2021; 12:1146. [PMID: 34440316 PMCID: PMC8391894 DOI: 10.3390/genes12081146] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 07/16/2021] [Accepted: 07/20/2021] [Indexed: 12/11/2022] Open
Abstract
The emergence of precision medicine from the development of Poly (ADP-ribose) polymerase (PARP) inhibitors that preferentially kill cells defective in homologous recombination has sparked wide interest in identifying and characterizing additional DNA repair enzymes that are synthetic lethal with HR factors. DNA polymerase theta (Polθ) is a validated anti-cancer drug target that is synthetic lethal with HR factors and other DNA repair proteins and confers cellular resistance to various genotoxic cancer therapies. Since its initial characterization as a helicase-polymerase fusion protein in 2003, many exciting and unexpected activities of Polθ in microhomology-mediated end-joining (MMEJ) and translesion synthesis (TLS) have been discovered. Here, we provide a short review of Polθ's DNA repair activities and its potential as a drug target and highlight a recent report that reveals Polθ as a naturally occurring reverse transcriptase (RT) in mammalian cells.
Collapse
Affiliation(s)
- Xiaojiang S. Chen
- Molecular and Computational Biology, USC Dornsife Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA;
| | - Richard T. Pomerantz
- Department of Biochemistry and Molecular Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA
| |
Collapse
|
32
|
Tomasini PP, Guecheva TN, Leguisamo NM, Péricart S, Brunac AC, Hoffmann JS, Saffi J. Analyzing the Opportunities to Target DNA Double-Strand Breaks Repair and Replicative Stress Responses to Improve Therapeutic Index of Colorectal Cancer. Cancers (Basel) 2021; 13:3130. [PMID: 34201502 PMCID: PMC8268241 DOI: 10.3390/cancers13133130] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 06/15/2021] [Accepted: 06/18/2021] [Indexed: 12/22/2022] Open
Abstract
Despite the ample improvements of CRC molecular landscape, the therapeutic options still rely on conventional chemotherapy-based regimens for early disease, and few targeted agents are recommended for clinical use in the metastatic setting. Moreover, the impact of cytotoxic, targeted agents, and immunotherapy combinations in the metastatic scenario is not fully satisfactory, especially the outcomes for patients who develop resistance to these treatments need to be improved. Here, we examine the opportunity to consider therapeutic agents targeting DNA repair and DNA replication stress response as strategies to exploit genetic or functional defects in the DNA damage response (DDR) pathways through synthetic lethal mechanisms, still not explored in CRC. These include the multiple actors involved in the repair of DNA double-strand breaks (DSBs) through homologous recombination (HR), classical non-homologous end joining (NHEJ), and microhomology-mediated end-joining (MMEJ), inhibitors of the base excision repair (BER) protein poly (ADP-ribose) polymerase (PARP), as well as inhibitors of the DNA damage kinases ataxia-telangiectasia and Rad3 related (ATR), CHK1, WEE1, and ataxia-telangiectasia mutated (ATM). We also review the biomarkers that guide the use of these agents, and current clinical trials with targeted DDR therapies.
Collapse
Affiliation(s)
- Paula Pellenz Tomasini
- Laboratory of Genetic Toxicology, Federal University of Health Sciences of Porto Alegre, Avenida Sarmento Leite, 245, Porto Alegre 90050-170, Brazil; (P.P.T.); (N.M.L.)
- Post-Graduation Program in Cell and Molecular Biology, Federal University of Rio Grande do Sul, Avenida Bento Gonçalves, 9500, Porto Alegre 91501-970, Brazil
| | - Temenouga Nikolova Guecheva
- Cardiology Institute of Rio Grande do Sul, University Foundation of Cardiology (IC-FUC), Porto Alegre 90620-000, Brazil;
| | - Natalia Motta Leguisamo
- Laboratory of Genetic Toxicology, Federal University of Health Sciences of Porto Alegre, Avenida Sarmento Leite, 245, Porto Alegre 90050-170, Brazil; (P.P.T.); (N.M.L.)
| | - Sarah Péricart
- Laboratoire D’Excellence Toulouse Cancer (TOUCAN), Laboratoire de Pathologie, Institut Universitaire du Cancer-Toulouse, Oncopole, 1 Avenue Irène-Joliot-Curie, 31059 Toulouse, France; (S.P.); (A.-C.B.); (J.S.H.)
| | - Anne-Cécile Brunac
- Laboratoire D’Excellence Toulouse Cancer (TOUCAN), Laboratoire de Pathologie, Institut Universitaire du Cancer-Toulouse, Oncopole, 1 Avenue Irène-Joliot-Curie, 31059 Toulouse, France; (S.P.); (A.-C.B.); (J.S.H.)
| | - Jean Sébastien Hoffmann
- Laboratoire D’Excellence Toulouse Cancer (TOUCAN), Laboratoire de Pathologie, Institut Universitaire du Cancer-Toulouse, Oncopole, 1 Avenue Irène-Joliot-Curie, 31059 Toulouse, France; (S.P.); (A.-C.B.); (J.S.H.)
| | - Jenifer Saffi
- Laboratory of Genetic Toxicology, Federal University of Health Sciences of Porto Alegre, Avenida Sarmento Leite, 245, Porto Alegre 90050-170, Brazil; (P.P.T.); (N.M.L.)
- Post-Graduation Program in Cell and Molecular Biology, Federal University of Rio Grande do Sul, Avenida Bento Gonçalves, 9500, Porto Alegre 91501-970, Brazil
| |
Collapse
|
33
|
Zatreanu D, Robinson HMR, Alkhatib O, Boursier M, Finch H, Geo L, Grande D, Grinkevich V, Heald RA, Langdon S, Majithiya J, McWhirter C, Martin NMB, Moore S, Neves J, Rajendra E, Ranzani M, Schaedler T, Stockley M, Wiggins K, Brough R, Sridhar S, Gulati A, Shao N, Badder LM, Novo D, Knight EG, Marlow R, Haider S, Callen E, Hewitt G, Schimmel J, Prevo R, Alli C, Ferdinand A, Bell C, Blencowe P, Bot C, Calder M, Charles M, Curry J, Ekwuru T, Ewings K, Krajewski W, MacDonald E, McCarron H, Pang L, Pedder C, Rigoreau L, Swarbrick M, Wheatley E, Willis S, Wong AC, Nussenzweig A, Tijsterman M, Tutt A, Boulton SJ, Higgins GS, Pettitt SJ, Smith GCM, Lord CJ. Polθ inhibitors elicit BRCA-gene synthetic lethality and target PARP inhibitor resistance. Nat Commun 2021; 12:3636. [PMID: 34140467 PMCID: PMC8211653 DOI: 10.1038/s41467-021-23463-8] [Citation(s) in RCA: 169] [Impact Index Per Article: 56.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 04/30/2021] [Indexed: 02/05/2023] Open
Abstract
To identify approaches to target DNA repair vulnerabilities in cancer, we discovered nanomolar potent, selective, low molecular weight (MW), allosteric inhibitors of the polymerase function of DNA polymerase Polθ, including ART558. ART558 inhibits the major Polθ-mediated DNA repair process, Theta-Mediated End Joining, without targeting Non-Homologous End Joining. In addition, ART558 elicits DNA damage and synthetic lethality in BRCA1- or BRCA2-mutant tumour cells and enhances the effects of a PARP inhibitor. Genetic perturbation screening revealed that defects in the 53BP1/Shieldin complex, which cause PARP inhibitor resistance, result in in vitro and in vivo sensitivity to small molecule Polθ polymerase inhibitors. Mechanistically, ART558 increases biomarkers of single-stranded DNA and synthetic lethality in 53BP1-defective cells whilst the inhibition of DNA nucleases that promote end-resection reversed these effects, implicating these in the synthetic lethal mechanism-of-action. Taken together, these observations describe a drug class that elicits BRCA-gene synthetic lethality and PARP inhibitor synergy, as well as targeting a biomarker-defined mechanism of PARPi-resistance.
Collapse
Affiliation(s)
- Diana Zatreanu
- CRUK Gene Function Laboratory, The Institute of Cancer Research, London, UK
- The Breast Cancer Now Toby Robins Research Centre, The Institute of Cancer Research, London, UK
| | - Helen M R Robinson
- Artios Pharma, The Glenn Berge Building, Babraham Research Campus, Cambridge, UK
| | - Omar Alkhatib
- Artios Pharma, The Glenn Berge Building, Babraham Research Campus, Cambridge, UK
| | - Marie Boursier
- Artios Pharma, The Glenn Berge Building, Babraham Research Campus, Cambridge, UK
| | - Harry Finch
- Artios Pharma, The Glenn Berge Building, Babraham Research Campus, Cambridge, UK
| | - Lerin Geo
- Artios Pharma, The Glenn Berge Building, Babraham Research Campus, Cambridge, UK
| | - Diego Grande
- Artios Pharma, The Glenn Berge Building, Babraham Research Campus, Cambridge, UK
| | - Vera Grinkevich
- Artios Pharma, The Glenn Berge Building, Babraham Research Campus, Cambridge, UK
| | - Robert A Heald
- Artios Pharma, The Glenn Berge Building, Babraham Research Campus, Cambridge, UK
| | - Sophie Langdon
- Artios Pharma, The Glenn Berge Building, Babraham Research Campus, Cambridge, UK
| | - Jayesh Majithiya
- Artios Pharma, The Glenn Berge Building, Babraham Research Campus, Cambridge, UK
| | - Claire McWhirter
- Artios Pharma, The Glenn Berge Building, Babraham Research Campus, Cambridge, UK
| | - Niall M B Martin
- Artios Pharma, The Glenn Berge Building, Babraham Research Campus, Cambridge, UK
| | - Shaun Moore
- Artios Pharma, The Glenn Berge Building, Babraham Research Campus, Cambridge, UK
| | - Joana Neves
- Artios Pharma, The Glenn Berge Building, Babraham Research Campus, Cambridge, UK
| | - Eeson Rajendra
- Artios Pharma, The Glenn Berge Building, Babraham Research Campus, Cambridge, UK
| | - Marco Ranzani
- Artios Pharma, The Glenn Berge Building, Babraham Research Campus, Cambridge, UK
| | - Theresia Schaedler
- Artios Pharma, The Glenn Berge Building, Babraham Research Campus, Cambridge, UK
| | - Martin Stockley
- Artios Pharma, The Glenn Berge Building, Babraham Research Campus, Cambridge, UK
| | - Kimberley Wiggins
- Artios Pharma, The Glenn Berge Building, Babraham Research Campus, Cambridge, UK
| | - Rachel Brough
- CRUK Gene Function Laboratory, The Institute of Cancer Research, London, UK
- The Breast Cancer Now Toby Robins Research Centre, The Institute of Cancer Research, London, UK
| | - Sandhya Sridhar
- CRUK Gene Function Laboratory, The Institute of Cancer Research, London, UK
- The Breast Cancer Now Toby Robins Research Centre, The Institute of Cancer Research, London, UK
| | - Aditi Gulati
- CRUK Gene Function Laboratory, The Institute of Cancer Research, London, UK
- The Breast Cancer Now Toby Robins Research Centre, The Institute of Cancer Research, London, UK
| | - Nan Shao
- CRUK Gene Function Laboratory, The Institute of Cancer Research, London, UK
- The Breast Cancer Now Toby Robins Research Centre, The Institute of Cancer Research, London, UK
| | - Luned M Badder
- The Breast Cancer Now Research Unit, King's College London, London, UK
| | - Daniela Novo
- The Breast Cancer Now Toby Robins Research Centre, The Institute of Cancer Research, London, UK
| | - Eleanor G Knight
- The Breast Cancer Now Toby Robins Research Centre, The Institute of Cancer Research, London, UK
| | - Rebecca Marlow
- The Breast Cancer Now Toby Robins Research Centre, The Institute of Cancer Research, London, UK
- The Breast Cancer Now Research Unit, King's College London, London, UK
| | - Syed Haider
- The Breast Cancer Now Toby Robins Research Centre, The Institute of Cancer Research, London, UK
| | - Elsa Callen
- Laboratory of Genome Integrity, National Cancer Institute, NIH, Bethesda, MD, USA
| | | | - Joost Schimmel
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Remko Prevo
- Medical Research Council Oxford Institute for Radiation Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford, UK
| | - Christina Alli
- Cancer Research UK, Therapeutic Discovery Laboratories, Jonas Webb Building, Babraham Research Campus, Cambridge, UK
| | - Amanda Ferdinand
- Cancer Research UK, Therapeutic Discovery Laboratories, Jonas Webb Building, Babraham Research Campus, Cambridge, UK
| | - Cameron Bell
- Cancer Research UK, Therapeutic Discovery Laboratories, Jonas Webb Building, Babraham Research Campus, Cambridge, UK
| | - Peter Blencowe
- Cancer Research UK, Therapeutic Discovery Laboratories, Jonas Webb Building, Babraham Research Campus, Cambridge, UK
| | - Chris Bot
- Cancer Research UK, Therapeutic Discovery Laboratories, Jonas Webb Building, Babraham Research Campus, Cambridge, UK
| | - Mathew Calder
- Cancer Research UK, Therapeutic Discovery Laboratories, Jonas Webb Building, Babraham Research Campus, Cambridge, UK
| | - Mark Charles
- Cancer Research UK, Therapeutic Discovery Laboratories, Jonas Webb Building, Babraham Research Campus, Cambridge, UK
| | - Jayne Curry
- Cancer Research UK, Therapeutic Discovery Laboratories, Jonas Webb Building, Babraham Research Campus, Cambridge, UK
| | - Tennyson Ekwuru
- Cancer Research UK, Therapeutic Discovery Laboratories, Jonas Webb Building, Babraham Research Campus, Cambridge, UK
| | - Katherine Ewings
- Cancer Research UK, Therapeutic Discovery Laboratories, Jonas Webb Building, Babraham Research Campus, Cambridge, UK
| | - Wojciech Krajewski
- Cancer Research UK, Therapeutic Discovery Laboratories, Jonas Webb Building, Babraham Research Campus, Cambridge, UK
| | - Ellen MacDonald
- Cancer Research UK, Therapeutic Discovery Laboratories, Jonas Webb Building, Babraham Research Campus, Cambridge, UK
| | - Hollie McCarron
- Cancer Research UK, Therapeutic Discovery Laboratories, Jonas Webb Building, Babraham Research Campus, Cambridge, UK
| | - Leon Pang
- Cancer Research UK, Therapeutic Discovery Laboratories, Jonas Webb Building, Babraham Research Campus, Cambridge, UK
| | - Chris Pedder
- Cancer Research UK, Therapeutic Discovery Laboratories, Jonas Webb Building, Babraham Research Campus, Cambridge, UK
| | - Laurent Rigoreau
- Cancer Research UK, Therapeutic Discovery Laboratories, Jonas Webb Building, Babraham Research Campus, Cambridge, UK
| | - Martin Swarbrick
- Cancer Research UK, Therapeutic Discovery Laboratories, Jonas Webb Building, Babraham Research Campus, Cambridge, UK
| | - Ed Wheatley
- Cancer Research UK, Therapeutic Discovery Laboratories, Jonas Webb Building, Babraham Research Campus, Cambridge, UK
| | - Simon Willis
- Cancer Research UK, Therapeutic Discovery Laboratories, Jonas Webb Building, Babraham Research Campus, Cambridge, UK
| | - Ai Ching Wong
- Cancer Research UK, Therapeutic Discovery Laboratories, Jonas Webb Building, Babraham Research Campus, Cambridge, UK
| | - Andre Nussenzweig
- Laboratory of Genome Integrity, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Marcel Tijsterman
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Andrew Tutt
- The Breast Cancer Now Toby Robins Research Centre, The Institute of Cancer Research, London, UK
- The Breast Cancer Now Research Unit, King's College London, London, UK
| | - Simon J Boulton
- Artios Pharma, The Glenn Berge Building, Babraham Research Campus, Cambridge, UK
- The Francis Crick Institute, London, UK
| | - Geoff S Higgins
- Medical Research Council Oxford Institute for Radiation Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford, UK
| | - Stephen J Pettitt
- CRUK Gene Function Laboratory, The Institute of Cancer Research, London, UK.
- The Breast Cancer Now Toby Robins Research Centre, The Institute of Cancer Research, London, UK.
| | - Graeme C M Smith
- Artios Pharma, The Glenn Berge Building, Babraham Research Campus, Cambridge, UK.
| | - Christopher J Lord
- CRUK Gene Function Laboratory, The Institute of Cancer Research, London, UK.
- The Breast Cancer Now Toby Robins Research Centre, The Institute of Cancer Research, London, UK.
| |
Collapse
|
34
|
Zhou J, Gelot C, Pantelidou C, Li A, Yücel H, Davis RE, Farkkila A, Kochupurakkal B, Syed A, Shapiro GI, Tainer JA, Blagg BSJ, Ceccaldi R, D’Andrea AD. A first-in-class Polymerase Theta Inhibitor selectively targets Homologous-Recombination-Deficient Tumors. NATURE CANCER 2021; 2:598-610. [PMID: 34179826 PMCID: PMC8224818 DOI: 10.1038/s43018-021-00203-x] [Citation(s) in RCA: 180] [Impact Index Per Article: 60.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
DNA polymerase theta (POLθ) is synthetic lethal with Homologous Recombination (HR) deficiency and thus a candidate target for HR-deficient cancers. Through high-throughput small molecule screens we identified the antibiotic Novobiocin (NVB) as a specific POLθ inhibitor that selectively kills HR-deficient tumor cells in vitro and in vivo. NVB directly binds to the POLθ ATPase domain, inhibits its ATPase activity, and phenocopies POLθ depletion. NVB kills HR-deficient breast and ovarian tumors in GEMM, xenograft and PDX models. Increased POLθ levels predict NVB sensitivity, and BRCA-deficient tumor cells with acquired resistance to PARP inhibitors (PARPi) are sensitive to NVB in vitro and in vivo. Mechanistically, NVB-mediated cell death in PARPi-resistant cells arises from increased double-strand break end resection, leading to accumulation of single-strand DNA intermediates and non-functional RAD51 foci. Our results demonstrate that NVB may be useful alone or in combination with PARPi in treating HR-deficient tumors, including those with acquired PARPi resistance. (151/150).
Collapse
Affiliation(s)
- Jia Zhou
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - Camille Gelot
- Inserm U830, PSL Research University, Institut Curie, 75005, Paris, France
| | - Constantia Pantelidou
- Department of Medical Oncology, Dana-Farber Cancer Institute and Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA
| | - Adam Li
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - Hatice Yücel
- Inserm U830, PSL Research University, Institut Curie, 75005, Paris, France
| | - Rachel E. Davis
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Anniina Farkkila
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - Bose Kochupurakkal
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - Aleem Syed
- Departments of Cancer Biology and of Molecular and Cellular Oncology, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Geoffrey I. Shapiro
- Department of Medical Oncology, Dana-Farber Cancer Institute and Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA.,Center for DNA Damage and Repair, Dana-Farber Cancer Institute, Boston, MA, USA
| | - John A. Tainer
- Departments of Cancer Biology and of Molecular and Cellular Oncology, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Brian S. J. Blagg
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Raphael Ceccaldi
- Inserm U830, PSL Research University, Institut Curie, 75005, Paris, France.,Corresponding authors: Alan D. D’Andrea, M.D., Director, Susan F. Smith Center for Women’s Cancers (SFSCWC), Director, Center for DNA Damage and Repair, Dana-Farber Cancer Institute, The Fuller-American Cancer Society Professor, Harvard Medical School, Phone: 617-632-2080, , Raphael Ceccaldi, Institut Curie, 75005, Paris, France, Phone: +33 (0)1 56 24 69 49,
| | - Alan D. D’Andrea
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA.,Center for DNA Damage and Repair, Dana-Farber Cancer Institute, Boston, MA, USA.,Susan F. Smith Center for Women’s Cancers, Dana-Farber Cancer Institute, Boston, MA, USA.,Corresponding authors: Alan D. D’Andrea, M.D., Director, Susan F. Smith Center for Women’s Cancers (SFSCWC), Director, Center for DNA Damage and Repair, Dana-Farber Cancer Institute, The Fuller-American Cancer Society Professor, Harvard Medical School, Phone: 617-632-2080, , Raphael Ceccaldi, Institut Curie, 75005, Paris, France, Phone: +33 (0)1 56 24 69 49,
| |
Collapse
|
35
|
Zahn KE, Jensen RB, Wood RD, Doublié S. RETRACTED: Human DNA polymerase θ harbors DNA end-trimming activity critical for DNA repair. Mol Cell 2021; 81:1534-1547.e4. [PMID: 33577776 PMCID: PMC8231307 DOI: 10.1016/j.molcel.2021.01.021] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 11/24/2020] [Accepted: 01/15/2021] [Indexed: 12/12/2022]
Abstract
Cancers with hereditary defects in homologous recombination rely on DNA polymerase θ (pol θ) for repair of DNA double-strand breaks. During end joining, pol θ aligns microhomology tracts internal to 5'-resected broken ends. An unidentified nuclease trims the 3' ends before synthesis can occur. Here we report that a nuclease activity, which differs from the proofreading activity often associated with DNA polymerases, is intrinsic to the polymerase domain of pol θ. Like the DNA synthesis activity, the nuclease activity requires conserved metal-binding residues, metal ions, and dNTPs and is inhibited by ddNTPs or chain-terminated DNA. Our data indicate that pol θ repurposes metal ions in the polymerase active site for endonucleolytic cleavage and that the polymerase-active and end-trimming conformations of the enzyme are distinct. We reveal a nimble strategy of substrate processing that allows pol θ to trim or extend DNA depending on the DNA repair context.
Collapse
Affiliation(s)
- Karl E Zahn
- Department of Microbiology and Molecular Genetics, University of Vermont, 89 Beaumont Ave., Burlington, VT 05405, USA; Department of Therapeutic Radiology, Yale University, New Haven, CT 06510, USA
| | - Ryan B Jensen
- Department of Therapeutic Radiology, Yale University, New Haven, CT 06510, USA
| | - Richard D Wood
- Department of Epigenetics & Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, TX 78957, USA.
| | - Sylvie Doublié
- Department of Microbiology and Molecular Genetics, University of Vermont, 89 Beaumont Ave., Burlington, VT 05405, USA.
| |
Collapse
|
36
|
Schrempf A, Slyskova J, Loizou JI. Targeting the DNA Repair Enzyme Polymerase θ in Cancer Therapy. Trends Cancer 2021; 7:98-111. [PMID: 33109489 DOI: 10.1016/j.trecan.2020.09.007] [Citation(s) in RCA: 91] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 09/21/2020] [Accepted: 09/28/2020] [Indexed: 12/21/2022]
Abstract
Targeted cancer therapies represent a milestone towards personalized treatment as they function via inhibition of cancer-specific alterations. Polymerase θ (POLQ), an error-prone translesion polymerase, also involved in DNA double-strand break (DSB) repair, is often upregulated in cancer. POLQ is synthetic lethal with various DNA repair genes, including known cancer drivers such as BRCA1/2, making it essential in homologous recombination-deficient cancers. Thus, POLQ represents a promising target in cancer therapy and efforts for the development of POLQ inhibitors are actively underway with first clinical trials due to start in 2021. This review summarizes the journey of POLQ from a backup DNA repair enzyme to a promising therapeutic target for cancer treatment.
Collapse
Affiliation(s)
- Anna Schrempf
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse 14, AKH BT 25.3, 1090 Vienna, Austria; Institute of Cancer Research, Department of Medicine I, Comprehensive Cancer Center, Medical University of Vienna, 1090 Vienna, Austria
| | - Jana Slyskova
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse 14, AKH BT 25.3, 1090 Vienna, Austria; Institute of Cancer Research, Department of Medicine I, Comprehensive Cancer Center, Medical University of Vienna, 1090 Vienna, Austria.
| | - Joanna I Loizou
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse 14, AKH BT 25.3, 1090 Vienna, Austria; Institute of Cancer Research, Department of Medicine I, Comprehensive Cancer Center, Medical University of Vienna, 1090 Vienna, Austria.
| |
Collapse
|
37
|
Van Vu T, Thi Hai Doan D, Kim J, Sung YW, Thi Tran M, Song YJ, Das S, Kim J. CRISPR/Cas-based precision genome editing via microhomology-mediated end joining. PLANT BIOTECHNOLOGY JOURNAL 2021; 19:230-239. [PMID: 33047464 PMCID: PMC7868975 DOI: 10.1111/pbi.13490] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 09/11/2020] [Accepted: 10/03/2020] [Indexed: 05/05/2023]
Abstract
Gene editing and/or allele introgression with absolute precision and control appear to be the ultimate goals of genetic engineering. Precision genome editing in plants has been developed through various approaches, including oligonucleotide-directed mutagenesis (ODM), base editing, prime editing and especially homologous recombination (HR)-based gene targeting. With the advent of CRISPR/Cas for the targeted generation of DNA breaks (single-stranded breaks (SSBs) or double-stranded breaks (DSBs)), a substantial advancement in HR-mediated precise editing frequencies has been achieved. Nonetheless, further research needs to be performed for commercially viable applications of precise genome editing; hence, an alternative innovative method for genome editing may be required. Within this scope, we summarize recent progress regarding precision genome editing mediated by microhomology-mediated end joining (MMEJ) and discuss their potential applications in crop improvement.
Collapse
Affiliation(s)
- Tien Van Vu
- Division of Applied Life Science (BK21 Plus Program)Plant Molecular Biology and Biotechnology Research CenterGyeongsang National UniversityJinju 660‐701Republic of Korea
- National Key Laboratory for Plant Cell BiotechnologyAgricultural Genetics InstituteKm 02, Pham Van Dong RoadCo Nhue 1, Bac Tu Liem, Hanoi11917Vietnam
| | - Duong Thi Hai Doan
- Division of Applied Life Science (BK21 Plus Program)Plant Molecular Biology and Biotechnology Research CenterGyeongsang National UniversityJinju 660‐701Republic of Korea
| | - Jihae Kim
- Division of Applied Life Science (BK21 Plus Program)Plant Molecular Biology and Biotechnology Research CenterGyeongsang National UniversityJinju 660‐701Republic of Korea
| | - Yeon Woo Sung
- Division of Applied Life Science (BK21 Plus Program)Plant Molecular Biology and Biotechnology Research CenterGyeongsang National UniversityJinju 660‐701Republic of Korea
| | - Mil Thi Tran
- Division of Applied Life Science (BK21 Plus Program)Plant Molecular Biology and Biotechnology Research CenterGyeongsang National UniversityJinju 660‐701Republic of Korea
| | - Young Jong Song
- Division of Applied Life Science (BK21 Plus Program)Plant Molecular Biology and Biotechnology Research CenterGyeongsang National UniversityJinju 660‐701Republic of Korea
| | - Swati Das
- Division of Applied Life Science (BK21 Plus Program)Plant Molecular Biology and Biotechnology Research CenterGyeongsang National UniversityJinju 660‐701Republic of Korea
| | - Jae‐Yean Kim
- Division of Applied Life Science (BK21 Plus Program)Plant Molecular Biology and Biotechnology Research CenterGyeongsang National UniversityJinju 660‐701Republic of Korea
- Division of Life ScienceGyeongsang National University501 Jinju‐daeroJinju52828Republic of Korea
| |
Collapse
|
38
|
Jenkins T, Northall SJ, Ptchelkine D, Lever R, Cubbon A, Betts H, Taresco V, Cooper CDO, McHugh PJ, Soultanas P, Bolt EL. The HelQ human DNA repair helicase utilizes a PWI-like domain for DNA loading through interaction with RPA, triggering DNA unwinding by the HelQ helicase core. NAR Cancer 2021; 3:zcaa043. [PMID: 34316696 PMCID: PMC8210318 DOI: 10.1093/narcan/zcaa043] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 11/30/2020] [Accepted: 12/16/2020] [Indexed: 01/04/2023] Open
Abstract
Genome instability is a characteristic enabling factor for carcinogenesis. HelQ helicase is a component of human DNA maintenance systems that prevent or reverse genome instability arising during DNA replication. Here, we provide details of the molecular mechanisms that underpin HelQ function-its recruitment onto ssDNA through interaction with replication protein A (RPA), and subsequent translocation of HelQ along ssDNA. We describe for the first time a functional role for the non-catalytic N-terminal region of HelQ, by identifying and characterizing its PWI-like domain. We present evidence that this domain of HelQ mediates interaction with RPA that orchestrates loading of the helicase domains onto ssDNA. Once HelQ is loaded onto the ssDNA, ATP-Mg2+ binding in the catalytic site activates the helicase core and triggers translocation along ssDNA as a dimer. Furthermore, we identify HelQ-ssDNA interactions that are critical for the translocation mechanism. Our data are novel and detailed insights into the mechanisms of HelQ function relevant for understanding how human cells avoid genome instability provoking cancers, and also how cells can gain resistance to treatments that rely on DNA crosslinking agents.
Collapse
Affiliation(s)
- Tabitha Jenkins
- School of Life Sciences, The University of Nottingham, NG7 2UH, Nottingham, UK
| | - Sarah J Northall
- School of Life Sciences, The University of Nottingham, NG7 2UH, Nottingham, UK
| | | | - Rebecca Lever
- School of Life Sciences, The University of Nottingham, NG7 2UH, Nottingham, UK
| | - Andrew Cubbon
- School of Life Sciences, The University of Nottingham, NG7 2UH, Nottingham, UK
| | - Hannah Betts
- School of Chemistry, The University of Nottingham, NG7 2RD, Nottingham, UK
| | - Vincenzo Taresco
- School of Pharmacy, The University of Nottingham, NG7 2RD, Nottingham, UK
| | - Christopher D O Cooper
- Department of Biological and Geographical Sciences, School of Applied Sciences, The University of Huddersfield, HD1 3DH, Huddersfield, UK
| | - Peter J McHugh
- MRC Weatherall Institute of Molecular Medicine (WIMM), University of Oxford, OX3 9DS, Oxford, UK
| | - Panos Soultanas
- School of Chemistry, The University of Nottingham, NG7 2RD, Nottingham, UK
| | - Edward L Bolt
- School of Life Sciences, The University of Nottingham, NG7 2UH, Nottingham, UK
| |
Collapse
|
39
|
Peralta-Castro A, García-Medel PL, Baruch-Torres N, Trasviña-Arenas CH, Juarez-Quintero V, Morales-Vazquez CM, Brieba LG. Plant Organellar DNA Polymerases Evolved Multifunctionality through the Acquisition of Novel Amino Acid Insertions. Genes (Basel) 2020; 11:genes11111370. [PMID: 33228188 PMCID: PMC7699545 DOI: 10.3390/genes11111370] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 11/15/2020] [Accepted: 11/17/2020] [Indexed: 12/20/2022] Open
Abstract
The majority of DNA polymerases (DNAPs) are specialized enzymes with specific roles in DNA replication, translesion DNA synthesis (TLS), or DNA repair. The enzymatic characteristics to perform accurate DNA replication are in apparent contradiction with TLS or DNA repair abilities. For instance, replicative DNAPs incorporate nucleotides with high fidelity and processivity, whereas TLS DNAPs are low-fidelity polymerases with distributive nucleotide incorporation. Plant organelles (mitochondria and chloroplast) are replicated by family-A DNA polymerases that are both replicative and TLS DNAPs. Furthermore, plant organellar DNA polymerases from the plant model Arabidopsis thaliana (AtPOLIs) execute repair of double-stranded breaks by microhomology-mediated end-joining and perform Base Excision Repair (BER) using lyase and strand-displacement activities. AtPOLIs harbor three unique insertions in their polymerization domain that are associated with TLS, microhomology-mediated end-joining (MMEJ), strand-displacement, and lyase activities. We postulate that AtPOLIs are able to execute those different functions through the acquisition of these novel amino acid insertions, making them multifunctional enzymes able to participate in DNA replication and DNA repair.
Collapse
Affiliation(s)
- Antolín Peralta-Castro
- Laboratorio Nacional de Genomica para la Biodiversidad, Centro de Investigacion y de Estudios Avanzados del IPN, Apartado Postal 629, Irapuato CP 36821, Mexico; (A.P.-C.); (P.L.G.-M.); (N.B.-T.); (C.H.T.-A.); (V.J.-Q.); (C.M.M.-V.)
| | - Paola L. García-Medel
- Laboratorio Nacional de Genomica para la Biodiversidad, Centro de Investigacion y de Estudios Avanzados del IPN, Apartado Postal 629, Irapuato CP 36821, Mexico; (A.P.-C.); (P.L.G.-M.); (N.B.-T.); (C.H.T.-A.); (V.J.-Q.); (C.M.M.-V.)
| | - Noe Baruch-Torres
- Laboratorio Nacional de Genomica para la Biodiversidad, Centro de Investigacion y de Estudios Avanzados del IPN, Apartado Postal 629, Irapuato CP 36821, Mexico; (A.P.-C.); (P.L.G.-M.); (N.B.-T.); (C.H.T.-A.); (V.J.-Q.); (C.M.M.-V.)
| | - Carlos H. Trasviña-Arenas
- Laboratorio Nacional de Genomica para la Biodiversidad, Centro de Investigacion y de Estudios Avanzados del IPN, Apartado Postal 629, Irapuato CP 36821, Mexico; (A.P.-C.); (P.L.G.-M.); (N.B.-T.); (C.H.T.-A.); (V.J.-Q.); (C.M.M.-V.)
- Department of Chemistry, University of California, Davis, One Shields Ave, Davis, CA 95616, USA
| | - Víctor Juarez-Quintero
- Laboratorio Nacional de Genomica para la Biodiversidad, Centro de Investigacion y de Estudios Avanzados del IPN, Apartado Postal 629, Irapuato CP 36821, Mexico; (A.P.-C.); (P.L.G.-M.); (N.B.-T.); (C.H.T.-A.); (V.J.-Q.); (C.M.M.-V.)
| | - Carlos M. Morales-Vazquez
- Laboratorio Nacional de Genomica para la Biodiversidad, Centro de Investigacion y de Estudios Avanzados del IPN, Apartado Postal 629, Irapuato CP 36821, Mexico; (A.P.-C.); (P.L.G.-M.); (N.B.-T.); (C.H.T.-A.); (V.J.-Q.); (C.M.M.-V.)
| | - Luis G. Brieba
- Laboratorio Nacional de Genomica para la Biodiversidad, Centro de Investigacion y de Estudios Avanzados del IPN, Apartado Postal 629, Irapuato CP 36821, Mexico; (A.P.-C.); (P.L.G.-M.); (N.B.-T.); (C.H.T.-A.); (V.J.-Q.); (C.M.M.-V.)
- Correspondence: ; Tel.: +52-462-1663007
| |
Collapse
|
40
|
Patterson-Fortin J, D'Andrea AD. Exploiting the Microhomology-Mediated End-Joining Pathway in Cancer Therapy. Cancer Res 2020; 80:4593-4600. [PMID: 32651257 PMCID: PMC7641946 DOI: 10.1158/0008-5472.can-20-1672] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 06/13/2020] [Accepted: 07/07/2020] [Indexed: 01/16/2023]
Abstract
Repair of DNA double-strand breaks (DSB) is performed by two major pathways, homology-dependent repair and classical nonhomologous end-joining. Recent studies have identified a third pathway, microhomology-mediated end-joining (MMEJ). MMEJ has similarities to homology-dependent repair, in that repair is initiated with end resection, leading to single-stranded 3' ends, which require microhomology upstream and downstream of the DSB. Importantly, the MMEJ pathway is commonly upregulated in cancers, especially in homologous recombination-deficient cancers, which display a distinctive mutational signature. Here, we review the molecular process of MMEJ as well as new targets and approaches exploiting the MMEJ pathway in cancer therapy.
Collapse
Affiliation(s)
| | - Alan D D'Andrea
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts.
- Center for DNA Damage and Repair, Dana-Farber Cancer Institute, Boston, Massachusetts
| |
Collapse
|
41
|
Acharya N, Khandagale P, Thakur S, Sahu JK, Utkalaja BG. Quaternary structural diversity in eukaryotic DNA polymerases: monomeric to multimeric form. Curr Genet 2020; 66:635-655. [PMID: 32236653 DOI: 10.1007/s00294-020-01071-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 03/13/2020] [Accepted: 03/24/2020] [Indexed: 12/14/2022]
Abstract
Sixteen eukaryotic DNA polymerases have been identified and studied so far. Based on the sequence similarity of the catalytic subunits of DNA polymerases, these have been classified into four A, B, X and Y families except PrimPol, which belongs to the AEP family. The quaternary structure of these polymerases also varies depending upon whether they are composed of one or more subunits. Therefore, in this review, we used a quaternary structure-based classification approach to group DNA polymerases as either monomeric or multimeric and highlighted functional significance of their accessory subunits. Additionally, we have briefly summarized various DNA polymerase discoveries from a historical perspective, emphasized unique catalytic mechanism of each DNA polymerase and highlighted recent advances in understanding their cellular functions.
Collapse
Affiliation(s)
- Narottam Acharya
- Laboratory of Genomic Instability and Diseases, Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, 751023, India.
| | - Prashant Khandagale
- Laboratory of Genomic Instability and Diseases, Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, 751023, India
| | - Shweta Thakur
- Laboratory of Genomic Instability and Diseases, Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, 751023, India
| | - Jugal Kishor Sahu
- Laboratory of Genomic Instability and Diseases, Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, 751023, India
| | - Bhabasha Gyanadeep Utkalaja
- Laboratory of Genomic Instability and Diseases, Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, 751023, India
| |
Collapse
|
42
|
Brambati A, Barry RM, Sfeir A. DNA polymerase theta (Polθ) - an error-prone polymerase necessary for genome stability. Curr Opin Genet Dev 2020; 60:119-126. [PMID: 32302896 PMCID: PMC7230004 DOI: 10.1016/j.gde.2020.02.017] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 02/13/2020] [Accepted: 02/14/2020] [Indexed: 12/21/2022]
Abstract
Mammalian cells have evolved multiple pathways to repair DNA double strand breaks (DSBs) and ensure genome stability. In addition to non-homologous end-joining (NHEJ) and homologous recombination (HR), cells evolved an error-prone repair pathway termed microhomology-mediated end joining (MMEJ). The mutagenic outcome of MMEJ derives from the activity of DNA polymerase theta (Polθ) - a multidomain enzyme that is minimally expressed in normal tissue but overexpressed in tumors. Polθ expression is particularly crucial for the proliferation of HR deficient cancer cells. As a result, this mutagenic repair emerged as an attractive target for cancer therapy, and inhibitors are currently in pre-clinical development. Here, we review the multifunctionality of this enigmatic polymerase, focusing on its role during DSB repair in mammalian cells and its impact on cancer genomes.
Collapse
Affiliation(s)
- Alessandra Brambati
- Skirball Institute of Biomolecular Medicine, Department of Cell Biology, NYU School of Medicine, New York, NY 10016, USA
| | - Raymond Mario Barry
- Skirball Institute of Biomolecular Medicine, Department of Cell Biology, NYU School of Medicine, New York, NY 10016, USA
| | - Agnel Sfeir
- Skirball Institute of Biomolecular Medicine, Department of Cell Biology, NYU School of Medicine, New York, NY 10016, USA.
| |
Collapse
|
43
|
Hoitsma NM, Whitaker AM, Schaich MA, Smith MR, Fairlamb MS, Freudenthal BD. Structure and function relationships in mammalian DNA polymerases. Cell Mol Life Sci 2020; 77:35-59. [PMID: 31722068 PMCID: PMC7050493 DOI: 10.1007/s00018-019-03368-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 10/11/2019] [Accepted: 10/31/2019] [Indexed: 12/19/2022]
Abstract
DNA polymerases are vital for the synthesis of new DNA strands. Since the discovery of DNA polymerase I in Escherichia coli, a diverse library of mammalian DNA polymerases involved in DNA replication, DNA repair, antibody generation, and cell checkpoint signaling has emerged. While the unique functions of these DNA polymerases are differentiated by their association with accessory factors and/or the presence of distinctive catalytic domains, atomic resolution structures of DNA polymerases in complex with their DNA substrates have revealed mechanistic subtleties that contribute to their specialization. In this review, the structure and function of all 15 mammalian DNA polymerases from families B, Y, X, and A will be reviewed and discussed with special emphasis on the insights gleaned from recently published atomic resolution structures.
Collapse
Affiliation(s)
- Nicole M Hoitsma
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Amy M Whitaker
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Matthew A Schaich
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Mallory R Smith
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Max S Fairlamb
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Bret D Freudenthal
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, 66160, USA.
| |
Collapse
|
44
|
DNA Helicases as Safekeepers of Genome Stability in Plants. Genes (Basel) 2019; 10:genes10121028. [PMID: 31835565 PMCID: PMC6947026 DOI: 10.3390/genes10121028] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 12/05/2019] [Accepted: 12/07/2019] [Indexed: 02/07/2023] Open
Abstract
Genetic information of all organisms is coded in double-stranded DNA. DNA helicases are essential for unwinding this double strand when it comes to replication, repair or transcription of genetic information. In this review, we will focus on what is known about a variety of DNA helicases that are required to ensure genome stability in plants. Due to their sessile lifestyle, plants are especially exposed to harmful environmental factors. Moreover, many crop plants have large and highly repetitive genomes, making them absolutely dependent on the correct interplay of DNA helicases for safeguarding their stability. Although basic features of a number of these enzymes are conserved between plants and other eukaryotes, a more detailed analysis shows surprising peculiarities, partly also between different plant species. This is additionally of high relevance for plant breeding as a number of these helicases are also involved in crossover control during meiosis and influence the outcome of different approaches of CRISPR/Cas based plant genome engineering. Thus, gaining knowledge about plant helicases, their interplay, as well as the manipulation of their pathways, possesses the potential for improving agriculture. In the long run, this might even help us cope with the increasing obstacles of climate change threatening food security in completely new ways.
Collapse
|
45
|
Estep KN, Butler TJ, Ding J, Brosh RM. G4-Interacting DNA Helicases and Polymerases: Potential Therapeutic Targets. Curr Med Chem 2019; 26:2881-2897. [PMID: 29149833 DOI: 10.2174/0929867324666171116123345] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 10/16/2017] [Accepted: 10/16/2017] [Indexed: 02/07/2023]
Abstract
BACKGROUND Guanine-rich DNA can fold into highly stable four-stranded DNA structures called G-quadruplexes (G4). In recent years, the G-quadruplex field has blossomed as new evidence strongly suggests that such alternately folded DNA structures are likely to exist in vivo. G4 DNA presents obstacles for the replication machinery, and both eukaryotic DNA helicases and polymerases have evolved to resolve and copy G4 DNA in vivo. In addition, G4-forming sequences are prevalent in gene promoters, suggesting that G4-resolving helicases act to modulate transcription. METHODS We have searched the PubMed database to compile an up-to-date and comprehensive assessment of the field's current knowledge to provide an overview of the molecular interactions of Gquadruplexes with DNA helicases and polymerases implicated in their resolution. RESULTS Novel computational tools and alternative strategies have emerged to detect G4-forming sequences and assess their biological consequences. Specialized DNA helicases and polymerases catalytically act upon G4-forming sequences to maintain normal replication and genomic stability as well as appropriate gene regulation and cellular homeostasis. G4 helicases also resolve telomeric repeats to maintain chromosomal DNA ends. Bypass of many G4-forming sequences is achieved by the action of translesion DNS polymerases or the PrimPol DNA polymerase. While the collective work has supported a role of G4 in nuclear DNA metabolism, an emerging field centers on G4 abundance in the mitochondrial genome. CONCLUSION Discovery of small molecules that specifically bind and modulate DNA helicases and polymerases or interact with the G4 DNA structure itself may be useful for the development of anticancer regimes.
Collapse
Affiliation(s)
- Katrina N Estep
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, NIH Biomedical Research Center, 251 Bayview Blvd Baltimore, MD 21224, United States
| | - Thomas J Butler
- Laboratory of Genetics and Genomics, National Institute on Aging, National Institutes of Health, NIH Biomedical Research Center, 251 Bayview Blvd Baltimore, MD 21224, United States
| | - Jun Ding
- Laboratory of Genetics and Genomics, National Institute on Aging, National Institutes of Health, NIH Biomedical Research Center, 251 Bayview Blvd Baltimore, MD 21224, United States
| | - Robert M Brosh
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, NIH Biomedical Research Center, 251 Bayview Blvd Baltimore, MD 21224, United States
| |
Collapse
|
46
|
Black SJ, Ozdemir AY, Kashkina E, Kent T, Rusanov T, Ristic D, Shin Y, Suma A, Hoang T, Chandramouly G, Siddique LA, Borisonnik N, Sullivan-Reed K, Mallon JS, Skorski T, Carnevale V, Murakami KS, Wyman C, Pomerantz RT. Molecular basis of microhomology-mediated end-joining by purified full-length Polθ. Nat Commun 2019; 10:4423. [PMID: 31562312 PMCID: PMC6764996 DOI: 10.1038/s41467-019-12272-9] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Accepted: 08/30/2019] [Indexed: 11/08/2022] Open
Abstract
DNA polymerase θ (Polθ) is a unique polymerase-helicase fusion protein that promotes microhomology-mediated end-joining (MMEJ) of DNA double-strand breaks (DSBs). How full-length human Polθ performs MMEJ at the molecular level remains unknown. Using a biochemical approach, we find that the helicase is essential for Polθ MMEJ of long ssDNA overhangs which model resected DSBs. Remarkably, Polθ MMEJ of ssDNA overhangs requires polymerase-helicase attachment, but not the disordered central domain, and occurs independently of helicase ATPase activity. Using single-particle microscopy and biophysical methods, we find that polymerase-helicase attachment promotes multimeric gel-like Polθ complexes that facilitate DNA accumulation, DNA synapsis, and MMEJ. We further find that the central domain regulates Polθ multimerization and governs its DNA substrate requirements for MMEJ. These studies identify unexpected functions for the helicase and central domain and demonstrate the importance of polymerase-helicase tethering in MMEJ and the structural organization of Polθ.
Collapse
Affiliation(s)
- Samuel J Black
- Fels Institute for Cancer Research, Department of Medical Genetics and Molecular Biochemistry, Temple University Lewis Katz School of Medicine, Philadelphia, PA, 19140, USA
| | - Ahmet Y Ozdemir
- Fels Institute for Cancer Research, Department of Medical Genetics and Molecular Biochemistry, Temple University Lewis Katz School of Medicine, Philadelphia, PA, 19140, USA
| | - Ekaterina Kashkina
- Fels Institute for Cancer Research, Department of Medical Genetics and Molecular Biochemistry, Temple University Lewis Katz School of Medicine, Philadelphia, PA, 19140, USA
| | - Tatiana Kent
- Fels Institute for Cancer Research, Department of Medical Genetics and Molecular Biochemistry, Temple University Lewis Katz School of Medicine, Philadelphia, PA, 19140, USA
| | - Timur Rusanov
- Fels Institute for Cancer Research, Department of Medical Genetics and Molecular Biochemistry, Temple University Lewis Katz School of Medicine, Philadelphia, PA, 19140, USA
| | - Dejan Ristic
- Department of Molecular Genetics and Department of Radiation Oncology, Erasmus University Medical Center, 3000 CA, Rotterdam, The Netherlands
| | - Yeonoh Shin
- Department of Biochemistry and Molecular Biology, The Center for RNA Molecular Biology, Pennsylvania State University, University Park, PA, 16802, USA
| | - Antonio Suma
- Institute for Computational Molecular Science, Temple University, Philadelphia, PA, USA
| | - Trung Hoang
- Fels Institute for Cancer Research, Department of Medical Genetics and Molecular Biochemistry, Temple University Lewis Katz School of Medicine, Philadelphia, PA, 19140, USA
| | - Gurushankar Chandramouly
- Fels Institute for Cancer Research, Department of Medical Genetics and Molecular Biochemistry, Temple University Lewis Katz School of Medicine, Philadelphia, PA, 19140, USA
| | - Labiba A Siddique
- Fels Institute for Cancer Research, Department of Medical Genetics and Molecular Biochemistry, Temple University Lewis Katz School of Medicine, Philadelphia, PA, 19140, USA
| | - Nikita Borisonnik
- Fels Institute for Cancer Research, Department of Medical Genetics and Molecular Biochemistry, Temple University Lewis Katz School of Medicine, Philadelphia, PA, 19140, USA
| | - Katherine Sullivan-Reed
- Fels Institute for Cancer Research, Department of Microbiology and Immunology, Temple University Lewis Katz School of Medicine, Philadelphia, PA, 19140, USA
| | - Joseph S Mallon
- Fels Institute for Cancer Research, Department of Medical Genetics and Molecular Biochemistry, Temple University Lewis Katz School of Medicine, Philadelphia, PA, 19140, USA
| | - Tomasz Skorski
- Fels Institute for Cancer Research, Department of Microbiology and Immunology, Temple University Lewis Katz School of Medicine, Philadelphia, PA, 19140, USA
| | - Vincenzo Carnevale
- Institute for Computational Molecular Science, Temple University, Philadelphia, PA, USA
| | - Katsuhiko S Murakami
- Department of Biochemistry and Molecular Biology, The Center for RNA Molecular Biology, Pennsylvania State University, University Park, PA, 16802, USA
| | - Claire Wyman
- Department of Molecular Genetics and Department of Radiation Oncology, Erasmus University Medical Center, 3000 CA, Rotterdam, The Netherlands
| | - Richard T Pomerantz
- Fels Institute for Cancer Research, Department of Medical Genetics and Molecular Biochemistry, Temple University Lewis Katz School of Medicine, Philadelphia, PA, 19140, USA.
| |
Collapse
|
47
|
Toma M, Skorski T, Sliwinski T. DNA Double Strand Break Repair - Related Synthetic Lethality. Curr Med Chem 2019; 26:1446-1482. [PMID: 29421999 DOI: 10.2174/0929867325666180201114306] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 11/10/2017] [Accepted: 11/16/2017] [Indexed: 12/25/2022]
Abstract
Cancer is a heterogeneous disease with a high degree of diversity between and within tumors. Our limited knowledge of their biology results in ineffective treatment. However, personalized approach may represent a milestone in the field of anticancer therapy. It can increase specificity of treatment against tumor initiating cancer stem cells (CSCs) and cancer progenitor cells (CPCs) with minimal effect on normal cells and tissues. Cancerous cells carry multiple genetic and epigenetic aberrations which may disrupt pathways essential for cell survival. Discovery of synthetic lethality has led a new hope of creating effective and personalized antitumor treatment. Synthetic lethality occurs when simultaneous inactivation of two genes or their products causes cell death whereas individual inactivation of either gene is not lethal. The effectiveness of numerous anti-tumor therapies depends on induction of DNA damage therefore tumor cells expressing abnormalities in genes whose products are crucial for DNA repair pathways are promising targets for synthetic lethality. Here, we discuss mechanistic aspects of synthetic lethality in the context of deficiencies in DNA double strand break repair pathways. In addition, we review clinical trials utilizing synthetic lethality interactions and discuss the mechanisms of resistance.
Collapse
Affiliation(s)
- Monika Toma
- Laboratory of Medical Genetics, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz, Poland
| | - Tomasz Skorski
- Department of Microbiology and Immunology, 3400 North Broad Street, Temple University Lewis Katz School of Medicine, Philadelphia, PA 19140, United States
| | - Tomasz Sliwinski
- Laboratory of Medical Genetics, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz, Poland
| |
Collapse
|
48
|
de Lima LP, Calderano SG, da Silva MS, de Araujo CB, Vasconcelos EJR, Iwai LK, Pereira CA, Fragoso SP, Elias MC. Ortholog of the polymerase theta helicase domain modulates DNA replication in Trypanosoma cruzi. Sci Rep 2019; 9:2888. [PMID: 30814563 PMCID: PMC6393585 DOI: 10.1038/s41598-019-39348-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 11/19/2018] [Indexed: 01/05/2023] Open
Abstract
DNA polymerase theta (Polθ), a member of the DNA polymerase family A, exhibits a polymerase C-terminal domain, a central domain, and an N-terminal helicase domain. Polθ plays important roles in DNA repair via its polymerase domain, regulating genome integrity. In addition, in mammals, Polθ modulates origin firing timing and MCM helicase recruitment to chromatin. In contrast, as a model eukaryote, Trypanosoma cruzi exhibits two individual putative orthologs of Polθ in different genomic loci; one ortholog is homologous to the Polθ C-terminal polymerase domain, and the other is homologous to the Polθ helicase domain, called Polθ-polymerase and Polθ-helicase, respectively. A pull-down assay using the T. cruzi component of the prereplication complex Orc1/Cdc6 as bait captured Polθ-helicase from the nuclear extract. Orc1/Cdc6 and Polθ-helicase directly interacted, and Polθ-helicase presented DNA unwinding and ATPase activities. A T. cruzi strain overexpressing the Polθ-helicase domain exhibited a significantly decreased amount of DNA-bound MCM7 and impaired replication origin firing. Taken together, these data suggest that Polθ-helicase modulates DNA replication by directly interacting with Orc1/Cdc6, which reduces the binding of MCM7 to DNA and thereby impairs the firing of replication origins.
Collapse
Affiliation(s)
- Loyze P de Lima
- Laboratorio Especial de Ciclo Celular, Instituto Butantan, São Paulo, Brazil
- Center of Toxins, Immune Response and Cell Signaling (CeTICS), Instituto Butantan, São Paulo, Brazil
| | | | - Marcelo S da Silva
- Laboratorio Especial de Ciclo Celular, Instituto Butantan, São Paulo, Brazil
- Center of Toxins, Immune Response and Cell Signaling (CeTICS), Instituto Butantan, São Paulo, Brazil
| | - Christiane B de Araujo
- Laboratorio Especial de Ciclo Celular, Instituto Butantan, São Paulo, Brazil
- Center of Toxins, Immune Response and Cell Signaling (CeTICS), Instituto Butantan, São Paulo, Brazil
| | - Elton J R Vasconcelos
- College of Veterinary Medicine, Western University of Health Sciences, Pomona, CA, 91766, USA
| | - Leo K Iwai
- Laboratório Especial de Toxinologia Aplicada, Instituto Butantan, São Paulo, Brazil
| | - Claudio A Pereira
- Laboratorio de Parasitología Molecular, Instituto de Investigaciones Médicas A. Lanari, Universidad de Buenos Aires - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Combatientes de Malvinas, (C1427ARO) Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | | | - M Carolina Elias
- Laboratorio Especial de Ciclo Celular, Instituto Butantan, São Paulo, Brazil.
- Center of Toxins, Immune Response and Cell Signaling (CeTICS), Instituto Butantan, São Paulo, Brazil.
| |
Collapse
|
49
|
Taheri-Ghahfarokhi A, Taylor BJ, Nitsch R, Lundin A, Cavallo AL, Madeyski-Bengtson K, Karlsson F, Clausen M, Hicks R, Mayr LM, Bohlooly-Y M, Maresca M. Decoding non-random mutational signatures at Cas9 targeted sites. Nucleic Acids Res 2018; 46:8417-8434. [PMID: 30032200 PMCID: PMC6144780 DOI: 10.1093/nar/gky653] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 07/05/2018] [Accepted: 07/09/2018] [Indexed: 12/15/2022] Open
Abstract
The mutation patterns at Cas9 targeted sites contain unique information regarding the nuclease activity and repair mechanisms in mammalian cells. However, analytical framework for extracting such information are lacking. Here, we present a novel computational platform called Rational InDel Meta-Analysis (RIMA) that enables an in-depth comprehensive analysis of Cas9-induced genetic alterations, especially InDels mutations. RIMA can be used to quantitate the contribution of classical microhomology-mediated end joining (c-MMEJ) pathway in the formation of mutations at Cas9 target sites. We used RIMA to compare mutational signatures at 15 independent Cas9 target sites in human A549 wildtype and A549-POLQ knockout cells to elucidate the role of DNA polymerase θ in c-MMEJ. Moreover, the single nucleotide insertions at the Cas9 target sites represent duplications of preceding nucleotides, suggesting that the flexibility of the Cas9 nuclease domains results in both blunt- and staggered-end cuts. Thymine at the fourth nucleotide before protospacer adjacent motif (PAM) results in a two-fold higher occurrence of single nucleotide InDels compared to guanine at the same position. This study provides a novel approach for the characterization of the Cas9 nucleases with improved accuracy in predicting genome editing outcomes and a potential strategy for homology-independent targeted genomic integration.
Collapse
Affiliation(s)
- Amir Taheri-Ghahfarokhi
- Translational Genomics, Discovery Sciences, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Benjamin J M Taylor
- Discovery Biology, Discovery Sciences, IMED Biotech Unit, AstraZeneca, Cambridge, UK
| | - Roberto Nitsch
- Translational Genomics, Discovery Sciences, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
- Advanced Medicines Safety, Drug Safety and Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Anders Lundin
- Translational Genomics, Discovery Sciences, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Anna-Lina Cavallo
- Translational Genomics, Discovery Sciences, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Katja Madeyski-Bengtson
- Translational Genomics, Discovery Sciences, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Fredrik Karlsson
- Quantitative Biology, Discovery Sciences, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Maryam Clausen
- Translational Genomics, Discovery Sciences, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Ryan Hicks
- Translational Genomics, Discovery Sciences, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Lorenz M Mayr
- Translational Genomics, Discovery Sciences, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
- GE Healthcare Life Sciences, The Grove Centre, White Lion Road, Amersham HP7 9LL, UK
| | - Mohammad Bohlooly-Y
- Translational Genomics, Discovery Sciences, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Marcello Maresca
- Translational Genomics, Discovery Sciences, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| |
Collapse
|
50
|
Abstract
DNA Pol θ-mediated end joining (TMEJ) is a microhomology-based pathway for repairing double-strand breaks in eukaryotes. TMEJ is also a pathway for nonspecific integration of foreign DNAs into host genomes. DNA Pol θ shares structural homology with the high-fidelity replicases, and its polymerase domain (Polθ) has been shown to extend ssDNA without an apparent template. Using oligonucleotides with distinct sequences, we find that with Mg2+ and physiological salt concentrations, human Polθ has no terminal transferase activity and requires a minimum of 2 bp and optimally 4 bp between a template/primer pair for DNA synthesis. Polθ can tolerate a mismatched base pair at the primer end but loses >90% activity when the mismatch is 2 bp upstream from the active site. Polθ is severely inhibited when the template strand has a 3' overhang within 3-4 bp from the active site. In line with its TMEJ function, Polθ has limited strand-displacement activity, and the efficiency and extent of primer extension are similar with or without a downstream duplex.
Collapse
Affiliation(s)
- Peng He
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Wei Yang
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| |
Collapse
|