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Tian LF, Gao H, Yang S, Liu YP, Li M, Xu W, Yan XX. Structure and function of extreme TLS DNA polymerase TTEDbh from Thermoanaerobacter tengcongensis. Int J Biol Macromol 2023; 253:126770. [PMID: 37683741 DOI: 10.1016/j.ijbiomac.2023.126770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2023] [Revised: 09/04/2023] [Accepted: 09/05/2023] [Indexed: 09/10/2023]
Abstract
Translesion synthesis (TLS) is a kind of DNA repair that maintains the stability of the genome and ensures the normal growth of life in cells under emergencies. Y-family DNA polymerases, as a kind of error-prone DNA polymerase, mainly perform TLS. Previous studies have suggested that the occurrence of tumors is associated with the overexpression of human DNA polymerase of the Y family. And the combination of Y-family DNA polymerase inhibitors is promising for cancer therapy. Here we report the functional and structural characterization of a member of the Y-family DNA polymerases, TTEDbh. We determine TTEDbh is an extreme TLS polymerase that can cross oxidative damage sites, and further identify the amino acids and novel structures that are critical for DNA binding, synthesis, fidelity, and oxidative damage bypass. Moreover, previously unnoticed structural elements with important functions have been discovered and analyzed. These studies provide a more experimental basis for further elucidating the molecular mechanisms of DNA polymerase in the Y family. It could also shed light on the design of drugs to target tumors.
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Affiliation(s)
- Li-Fei Tian
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Hongwei Gao
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shuyu Yang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yan-Ping Liu
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Mingzhou Li
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wenqing Xu
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China; School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China.
| | - Xiao-Xue Yan
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China.
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2
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Second-Shell Basic Residues Expand the Two-Metal-Ion Architecture of DNA and RNA Processing Enzymes. Structure 2017; 26:40-50.e2. [PMID: 29225080 PMCID: PMC5758106 DOI: 10.1016/j.str.2017.11.008] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 09/12/2017] [Accepted: 11/12/2017] [Indexed: 02/01/2023]
Abstract
Synthesis and scission of phosphodiester bonds in DNA and RNA regulate vital processes within the cell. Enzymes that catalyze these reactions operate mostly via the recognized two-metal-ion mechanism. Our analysis reveals that basic amino acids and monovalent cations occupy structurally conserved positions nearby the active site of many two-metal-ion enzymes for which high-resolution (<3 Å) structures are known, including DNA and RNA polymerases, nucleases such as Cas9, and splicing ribozymes. Integrating multiple-sequence and structural alignments with molecular dynamics simulations, electrostatic potential maps, and mutational data, we found that these elements always interact with the substrates, suggesting that they may play an active role for catalysis, in addition to their electrostatic contribution. We discuss possible mechanistic implications of this expanded two-metal-ion architecture, including inferences on medium-resolution cryoelectron microscopy structures. Ultimately, our analysis may inspire future experiments and strategies for enzyme engineering or drug design to modulate nucleic acid processing. Basic residues in the active site of two-metal-ion enzymes are structurally conserved These residues are also conserved in evolution Mutagenesis suggests these residues may exert an effect on DNA- and RNA processing Our work offers insights into CRISPR/Cas9, spliceosome, and DNA/RNA polymerases
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3
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Nishimoto N, Suzuki M, Izuta S. Effect of pH on the Misincorporation Rate of DNA Polymerase η. Biol Pharm Bull 2017; 39:953-8. [PMID: 27251497 DOI: 10.1248/bpb.b15-00900] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The many known eukaryotic DNA polymerases are classified into four families; A, B, X, and Y. Among them, DNA polymerase η, a Y family polymerase, is a low fidelity enzyme that contributes to translesional synthesis and somatic hypermutation. Although a high mutation frequency is observed in immunoglobulin genes, translesional synthesis occurs with a high accuracy. We determined whether the misincorporation rate of DNA polymerase η varies with ambient conditions. It has been reported that DNA polymerase η is unable to exclude water molecules from the active site. This finding suggests that some ions affect hydrogen bond formation at the active site. We focused on the effect of pH and evaluated the misincorporation rate of deoxyguanosine triphosphate (dGTP) opposite template T by DNA polymerase η at various pH levels with a synthetic template-primer. The misincorporation rate of dGTP by DNA polymerase η drastically increased at pH 8.0-9.0 compared with that at pH 6.5-7.5. Kinetic analysis revealed that the Km value for dGTP on the misincorporation opposite template T was markedly affected by pH. However, this drastic change was not seen with the low fidelity DNA polymerase α.
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Affiliation(s)
- Naomi Nishimoto
- Graduate School of Science and Technology, Kumamoto University
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4
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Choi JY, Patra A, Yeom M, Lee YS, Zhang Q, Egli M, Guengerich FP. Kinetic and Structural Impact of Metal Ions and Genetic Variations on Human DNA Polymerase ι. J Biol Chem 2016; 291:21063-21073. [PMID: 27555320 DOI: 10.1074/jbc.m116.748285] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Indexed: 12/13/2022] Open
Abstract
DNA polymerase (pol) ι is a Y-family polymerase involved in translesion synthesis, exhibiting higher catalytic activity with Mn2+ than Mg2+ The human germline R96G variant impairs both Mn2+-dependent and Mg2+-dependent activities of pol ι, whereas the Δ1-25 variant selectively enhances its Mg2+-dependent activity. We analyzed pre-steady-state kinetic and structural effects of these two metal ions and genetic variations on pol ι using pol ι core (residues 1-445) proteins. The presence of Mn2+ (0.15 mm) instead of Mg2+ (2 mm) caused a 770-fold increase in efficiency (kpol/Kd,dCTP) of pol ι for dCTP insertion opposite G, mainly due to a 450-fold decrease in Kd,dCTP The R96G and Δ1-25 variants displayed a 53-fold decrease and a 3-fold increase, respectively, in kpol/Kd,dCTP for dCTP insertion opposite G with Mg2+ when compared with wild type, substantially attenuated by substitution with Mn2+ Crystal structures of pol ι ternary complexes, including the primer terminus 3'-OH and a non-hydrolyzable dCTP analogue opposite G with the active-site Mg2+ or Mn2+, revealed that Mn2+ achieves more optimal octahedral coordination geometry than Mg2+, with lower values in average coordination distance geometry in the catalytic metal A-site. Crystal structures of R96G revealed the loss of three H-bonds of residues Gly-96 and Tyr-93 with an incoming dNTP, due to the lack of an arginine, as well as a destabilized Tyr-93 side chain secondary to the loss of a cation-π interaction between both side chains. These results provide a mechanistic basis for alteration in pol ι catalytic function with coordinating metals and genetic variation.
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Affiliation(s)
- Jeong-Yun Choi
- From the Division of Pharmacology, Department of Molecular Cell Biology, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Gyeonggi-do 16419, Republic of Korea
| | - Amritaj Patra
- the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, and
| | - Mina Yeom
- From the Division of Pharmacology, Department of Molecular Cell Biology, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Gyeonggi-do 16419, Republic of Korea
| | - Young-Sam Lee
- the Department of New Biology, Daegu Gyeongbuk Institute of Science and Technology, Daegu 42988, Republic of Korea
| | - Qianqian Zhang
- the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, and
| | - Martin Egli
- the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, and
| | - F Peter Guengerich
- the Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, and
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5
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Kim J, Song I, Jo A, Shin JH, Cho H, Eoff RL, Guengerich FP, Choi JY. Biochemical analysis of six genetic variants of error-prone human DNA polymerase ι involved in translesion DNA synthesis. Chem Res Toxicol 2014; 27:1837-52. [PMID: 25162224 PMCID: PMC4203391 DOI: 10.1021/tx5002755] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
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DNA
polymerase (pol) ι is the most error-prone among the
Y-family polymerases that participate in translesion synthesis (TLS).
Pol ι can bypass various DNA lesions, e.g., N2-ethyl(Et)G, O6-methyl(Me)G,
8-oxo-7,8-dihydroguanine (8-oxoG), and an abasic site, though frequently
with low fidelity. We assessed the biochemical effects of six reported
genetic variations of human pol ι on its TLS properties, using
the recombinant pol ι (residues 1–445) proteins and DNA
templates containing a G, N2-EtG, O6-MeG, 8-oxoG, or abasic site. The Δ1–25
variant, which is the N-terminal truncation of 25
residues resulting from an initiation codon variant (c.3G > A)
and
also is the formerly misassigned wild-type, exhibited considerably
higher polymerase activity than wild-type with Mg2+ (but
not with Mn2+), coinciding with its steady-state kinetic
data showing a ∼10-fold increase in kcat/Km for nucleotide incorporation
opposite templates (only with Mg2+). The R96G variant,
which lacks a R96 residue known to interact with the incoming nucleotide,
lost much of its polymerase activity, consistent with the kinetic
data displaying 5- to 72-fold decreases in kcat/Km for nucleotide incorporation
opposite templates either with Mg2+ or Mn2+,
except for that opposite N2-EtG with Mn2+ (showing a 9-fold increase for dCTP incorporation). The
Δ1–25 variant bound DNA 20- to 29-fold more tightly than
wild-type (with Mg2+), but the R96G variant bound DNA 2-fold
less tightly than wild-type. The DNA-binding affinity of wild-type,
but not of the Δ1–25 variant, was ∼7-fold stronger
with 0.15 mM Mn2+ than with Mg2+. The results
indicate that the R96G variation severely impairs most of the Mg2+- and Mn2+-dependent TLS abilities of pol ι,
whereas the Δ1–25 variation selectively and substantially
enhances the Mg2+-dependent TLS capability of pol ι,
emphasizing the potential translational importance of these pol ι
genetic variations, e.g., individual differences in TLS, mutation,
and cancer susceptibility to genotoxic carcinogens.
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Affiliation(s)
- Jinsook Kim
- Division of Pharmacology, Department of Molecular Cell Biology, and ‡Department of Physiology, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine , Suwon, Gyeonggi-do 440-746, Republic of Korea
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6
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Sharma A, Kottur J, Narayanan N, Nair DT. A strategically located serine residue is critical for the mutator activity of DNA polymerase IV from Escherichia coli. Nucleic Acids Res 2013; 41:5104-14. [PMID: 23525461 PMCID: PMC3643571 DOI: 10.1093/nar/gkt146] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The Y-family DNA polymerase IV or PolIV (Escherichia coli) is the founding member of the DinB family and is known to play an important role in stress-induced mutagenesis. We have determined four crystal structures of this enzyme in its pre-catalytic state in complex with substrate DNA presenting the four possible template nucleotides that are paired with the corresponding incoming nucleotide triphosphates. In all four structures, the Ser42 residue in the active site forms interactions with the base moieties of the incipient Watson–Crick base pair. This residue is located close to the centre of the nascent base pair towards the minor groove. In vitro and in vivo assays show that the fidelity of the PolIV enzyme increases drastically when this Ser residue was mutated to Ala. In addition, the structure of PolIV with the mismatch A:C in the active site shows that the Ser42 residue plays an important role in stabilizing dCTP in a conformation compatible with catalysis. Overall, the structural, biochemical and functional data presented here show that the Ser42 residue is present at a strategic location to stabilize mismatches in the PolIV active site, and thus facilitate the appearance of transition and transversion mutations.
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Affiliation(s)
- Amit Sharma
- National Centre for Biological Sciences (NCBS-TIFR), UAS-GKVK Campus, Bellary Road, Bangalore 560065, India
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7
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Makarova AV, Kulbachinskiy AV. Structure of human DNA polymerase iota and the mechanism of DNA synthesis. BIOCHEMISTRY (MOSCOW) 2012; 77:547-61. [PMID: 22817454 DOI: 10.1134/s0006297912060016] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Cellular DNA polymerases belong to several families and carry out different functions. Highly accurate replicative DNA polymerases play the major role in cell genome replication. A number of new specialized DNA polymerases were discovered at the turn of XX-XXI centuries and have been intensively studied during the last decade. Due to the special structure of the active site, these enzymes efficiently perform synthesis on damaged DNA but are characterized by low fidelity. Human DNA polymerase iota (Pol ι) belongs to the Y-family of specialized DNA polymerases and is one of the most error-prone enzymes involved in DNA synthesis. In contrast to other DNA polymerases, Pol ι is able to use noncanonical Hoogsteen interactions for nucleotide base pairing. This allows it to incorporate nucleotides opposite various lesions in the DNA template that impair Watson-Crick interactions. Based on the data of X-ray structural analysis of Pol ι in complexes with various DNA templates and dNTP substrates, we consider the structural peculiarities of the Pol ι active site and discuss possible mechanisms that ensure the unique behavior of the enzyme on damaged and undamaged DNA.
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Affiliation(s)
- A V Makarova
- Institute of Molecular Genetics, Russian Academy of Sciences, pl. Kurchatova 2, 123182 Moscow, Russia.
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8
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Niida H, Katsuno Y, Sengoku M, Shimada M, Yukawa M, Ikura M, Ikura T, Kohno K, Shima H, Suzuki H, Tashiro S, Nakanishi M. Essential role of Tip60-dependent recruitment of ribonucleotide reductase at DNA damage sites in DNA repair during G1 phase. Genes Dev 2010; 24:333-8. [PMID: 20159953 DOI: 10.1101/gad.1863810] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
A balanced deoxyribonucleotide (dNTP) supply is essential for DNA repair. Here, we found that ribonucleotide reductase (RNR) subunits RRM1 and RRM2 accumulated very rapidly at damage sites. RRM1 bound physically to Tip60. Chromatin immunoprecipitation analyses of cells with an I-SceI cassette revealed that RRM1 bound to a damage site in a Tip60-dependent manner. Active RRM1 mutants lacking Tip60 binding failed to rescue an impaired DNA repair in RRM1-depleted G1-phase cells. Inhibition of RNR recruitment by an RRM1 C-terminal fragment sensitized cells to DNA damage. We propose that Tip60-dependent recruitment of RNR plays an essential role in dNTP supply for DNA repair.
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Affiliation(s)
- Hiroyuki Niida
- Department of Cell Biology, Graduate School of Medical Sciences, Nagoya City University Medical School, Nagoya 467-8601, Japan
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9
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Cruet-Hennequart S, Gallagher K, Sokòl AM, Villalan S, Prendergast AM, Carty MP. DNA polymerase eta, a key protein in translesion synthesis in human cells. Subcell Biochem 2010; 50:189-209. [PMID: 20012583 DOI: 10.1007/978-90-481-3471-7_10] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Genomic DNA is constantly damaged by exposure to exogenous and endogenous agents. Bulky adducts such as UV-induced cyclobutane pyrimidine dimers (CPDs) in the template DNA present a barrier to DNA synthesis by the major eukaryotic replicative polymerases including DNA polymerase delta. Translesion synthesis (TLS) carried out by specialized DNA polymerases is an evolutionarily conserved mechanism of DNA damage tolerance. The Y family of DNA polymerases, including DNA polymerase eta (Pol eta), the subject of this chapter, play a key role in TLS. Mutations in the human POLH gene encoding Pol eta underlie the genetic disease xeroderma pigmentosum variant (XPV), characterized by sun sensitivity, elevated incidence of skin cancer, and at the cellular level, by delayed replication and hypermutability after UV-irradiation. Pol eta is a low fidelity enzyme when copying undamaged DNA, but can carry out error-free TLS at sites of UV-induced dithymine CPDs. The active site of Pol eta has an open conformation that can accommodate CPDs, as well as cisplatin-induced intrastrand DNA crosslinks. Pol eta is recruited to sites of replication arrest in a tightly regulated process through interaction with PCNA. Pol eta-deficient cells show strong activation of downstream DNA damage responses including ATR signaling, and accumulate strand breaks as a result of replication fork collapse. Thus, Pol eta plays an important role in preventing genome instability after UV- and cisplatin-induced DNA damage. Inhibition of DNA damage tolerance pathways in tumors might also represent an approach to potentiate the effects of DNA damaging agents such as cisplatin.
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Affiliation(s)
- Séverine Cruet-Hennequart
- Centre for Chromosome Biology, School of Natural Sciences, National University of Ireland, Galway, Galway, Galway, Ireland
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10
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Waters LS, Minesinger BK, Wiltrout ME, D'Souza S, Woodruff RV, Walker GC. Eukaryotic translesion polymerases and their roles and regulation in DNA damage tolerance. Microbiol Mol Biol Rev 2009; 73:134-54. [PMID: 19258535 PMCID: PMC2650891 DOI: 10.1128/mmbr.00034-08] [Citation(s) in RCA: 440] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
DNA repair and DNA damage tolerance machineries are crucial to overcome the vast array of DNA damage that a cell encounters during its lifetime. In this review, we summarize the current state of knowledge about the eukaryotic DNA damage tolerance pathway translesion synthesis (TLS), a process in which specialized DNA polymerases replicate across from DNA lesions. TLS aids in resistance to DNA damage, presumably by restarting stalled replication forks or filling in gaps that remain in the genome due to the presence of DNA lesions. One consequence of this process is the potential risk of introducing mutations. Given the role of these translesion polymerases in mutagenesis, we discuss the significant regulatory mechanisms that control the five known eukaryotic translesion polymerases: Rev1, Pol zeta, Pol kappa, Pol eta, and Pol iota.
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Affiliation(s)
- Lauren S Waters
- Department of Biology, Massachusetts Institute of Technology, Building 68, Room 653, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
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11
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Stafford JB, Eoff RL, Kozekova A, Rizzo CJ, Guengerich FP, Marnett LJ. Translesion DNA synthesis by human DNA polymerase eta on templates containing a pyrimidopurinone deoxyguanosine adduct, 3-(2'-deoxy-beta-d-erythro-pentofuranosyl)pyrimido-[1,2-a]purin-10(3H)-one. Biochemistry 2009; 48:471-80. [PMID: 19108641 PMCID: PMC2651650 DOI: 10.1021/bi801591a] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
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M1dG (3-(2′-deoxy-β-d-erythro-pentofuranosyl)pyrimido[1,2-a]purin-10(3H)-one) lesions are mutagenic in bacterial and mammalian cells, leading to base substitutions (mostly M1dG to dT and M1dG to dA) and frameshift mutations. M1dG is produced endogenously through the reaction of peroxidation products, base propenal or malondialdehyde, with deoxyguanosine residues in DNA. The mutagenicity of M1dG in Escherichia coli is dependent on the SOS response, specifically the umuC and umuD gene products, suggesting that mutagenic lesion bypass occurs by the action of translesion DNA polymerases, like DNA polymerase V. Bypass of DNA lesions by translesion DNA polymerases is conserved in bacteria, yeast, and mammalian cells. The ability of recombinant human DNA polymerase η to synthesize DNA across from M1dG was studied. M1dG partially blocked DNA synthesis by polymerase η. Using steady-state kinetics, we found that insertion of dCTP was the least favored insertion product opposite the M1dG lesion (800-fold less efficient than opposite dG). Extension from M1dG·dC was equally as efficient as from control primer-templates (dG·dC). dATP insertion opposite M1dG was the most favored insertion product (8-fold less efficient than opposite dG), but extension from M1dG·dA was 20-fold less efficient than dG·dC. The sequences of full-length human DNA polymerase η bypass products of M1dG were determined by LC-ESI/MS/MS. Bypass products contained incorporation of dA (52%) or dC (16%) opposite M1dG or −1 frameshifts at the lesion site (31%). Human DNA polymerase η bypass may lead to M1dG to dT and frameshift but likely not M1dG to dA mutations during DNA replication.
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Affiliation(s)
- Jennifer B Stafford
- Department of Chemistry, A. B. Hancock, Jr., Memorial Laboratory for Cancer Research, Center in Molecular Toxicology, Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, USA
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12
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Anderson HJ, Vonarx EJ, Pastushok L, Nakagawa M, Katafuchi A, Gruz P, Di Rubbo A, Grice DM, Osmond MJ, Sakamoto AN, Nohmi T, Xiao W, Kunz BA. Arabidopsis thaliana Y-family DNA polymerase eta catalyses translesion synthesis and interacts functionally with PCNA2. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2008; 55:895-908. [PMID: 18494853 DOI: 10.1111/j.1365-313x.2008.03562.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Upon blockage of chromosomal replication by DNA lesions, Y-family polymerases interact with monoubiquitylated proliferating cell nuclear antigen (PCNA) to catalyse translesion synthesis (TLS) and restore replication fork progression. Here, we assessed the roles of Arabidopsis thaliana POLH, which encodes a homologue of Y-family polymerase eta (Poleta), PCNA1 and PCNA2 in TLS-mediated UV resistance. A T-DNA insertion in POLH sensitized the growth of roots and whole plants to UV radiation, indicating that AtPoleta contributes to UV resistance. POLH alone did not complement the UV sensitivity conferred by deletion of yeast RAD30, which encodes Poleta, although AtPoleta exhibited cyclobutane dimer bypass activity in vitro, and interacted with yeast PCNA, as well as with Arabidopsis PCNA1 and PCNA2. Co-expression of POLH and PCNA2, but not PCNA1, restored normal UV resistance and mutation kinetics in the rad30 mutant. A single residue difference at site 201, which lies adjacent to the residue (lysine 164) ubiquitylated in PCNA, appeared responsible for the inability of PCNA1 to function with AtPoleta in UV-treated yeast. PCNA-interacting protein boxes and an ubiquitin-binding motif in AtPoleta were found to be required for the restoration of UV resistance in the rad30 mutant by POLH and PCNA2. These observations indicate that AtPoleta can catalyse TLS past UV-induced DNA damage, and links the biological activity of AtPoleta in UV-irradiated cells to PCNA2 and PCNA- and ubiquitin-binding motifs in AtPoleta.
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Affiliation(s)
- Heather J Anderson
- School of Life and Environmental Sciences, Deakin University, Geelong, Vic. 3217, Australia
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13
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Wong JH, Fiala KA, Suo Z, Ling H. Snapshots of a Y-family DNA polymerase in replication: substrate-induced conformational transitions and implications for fidelity of Dpo4. J Mol Biol 2008; 379:317-30. [PMID: 18448122 DOI: 10.1016/j.jmb.2008.03.038] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2007] [Revised: 02/19/2008] [Accepted: 03/19/2008] [Indexed: 11/24/2022]
Abstract
Y-family DNA polymerases catalyze translesion DNA synthesis over damaged DNA. Each Y-family polymerase has a polymerase core consisting of a palm, finger and thumb domain in addition to a fourth domain known as a little finger domain. It is unclear how each domain moves during nucleotide incorporation and what type of conformational changes corresponds to the rate-limiting step previously reported in kinetic studies. Here, we present three crystal structures of the prototype Y-family polymerase: apo-Dpo4 at 1.9 A resolution, Dpo4-DNA binary complex and Dpo4-DNA-dTMP ternary complex at 2.2 A resolution. Dpo4 undergoes dramatic conformational changes from the apo to the binary structures with a 131 degrees rotation of the little finger domain relative to the polymerase core upon DNA binding. This DNA-induced conformational change is verified in solution by our tryptophan fluorescence studies. In contrast, the polymerase core retains the same conformation in all three conformationally distinct states. Particularly, the finger domain which is responsible for checking base pairing between the template base and an incoming nucleotide retains a rigid conformation. The inflexibility of the polymerase core likely contributes to the low fidelity of Dpo4, in addition to its loose and solvent-accessible active site. Interestingly, while the binary and ternary complexes of Dpo4 retain an identical global conformation, the aromatic side chains of two conserved tyrosines at the nucleotide-binding site change orientations between the binary and ternary structures. Such local conformational changes may correspond to the rate-limiting step in the mechanism of nucleotide incorporation. Together, the global and local conformational transitions observed in our study provide a structural basis for the distinct kinetic steps of a catalytic cycle of DNA polymerization performed by a Y-family polymerase.
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Affiliation(s)
- Jimson H Wong
- Department of Biochemistry, University of Western Ontario, London, Ontario, Canada
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14
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Lone S, Townson SA, Uljon SN, Johnson RE, Brahma A, Nair DT, Prakash S, Prakash L, Aggarwal AK. Human DNA polymerase kappa encircles DNA: implications for mismatch extension and lesion bypass. Mol Cell 2007; 25:601-14. [PMID: 17317631 DOI: 10.1016/j.molcel.2007.01.018] [Citation(s) in RCA: 173] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2006] [Revised: 10/22/2006] [Accepted: 01/17/2007] [Indexed: 10/23/2022]
Abstract
Human DNA polymerase kappa (Pol kappa) is a proficient extender of mispaired primer termini on undamaged DNAs and is implicated in the extension step of lesion bypass. We present here the structure of Pol kappa catalytic core in ternary complex with DNA and an incoming nucleotide. The structure reveals encirclement of the DNA by a unique "N-clasp" at the N terminus of Pol kappa, which augments the conventional right-handed grip on the DNA by the palm, fingers, and thumb domains and the PAD and provides additional thermodynamic stability. The structure also reveals an active-site cleft that is constrained by the close apposition of the N-clasp and the fingers domain, and therefore can accommodate only a single Watson-Crick base pair. Together, DNA encirclement and other structural features help explain Pol kappa's ability to extend mismatches and to promote replication through various minor groove DNA lesions, by extending from the nucleotide incorporated opposite the lesion by another polymerase.
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Affiliation(s)
- Samer Lone
- Department of Structural and Chemical Biology, Mount Sinai School of Medicine, Box 1677, 1425 Madison Avenue, New York, NY 10029, USA
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15
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Nair DT, Johnson RE, Prakash L, Prakash S, Aggarwal AK. An incoming nucleotide imposes an anti to syn conformational change on the templating purine in the human DNA polymerase-iota active site. Structure 2006; 14:749-55. [PMID: 16615915 DOI: 10.1016/j.str.2006.01.010] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2005] [Revised: 01/12/2006] [Accepted: 01/12/2006] [Indexed: 10/24/2022]
Abstract
Substrate-induced conformational change of the protein is the linchpin of enzymatic reactions. Replicative DNA polymerases, for example, convert from an open to a closed conformation in response to dNTP binding. Human DNA polymerase-iota (hPoliota), a member of the Y family of DNA polymerases, differs strikingly from other polymerases in its much higher proficiency and fidelity for nucleotide incorporation opposite template purines than opposite template pyrimidines. We present here a crystallographic analysis of hPoliota binary complexes, which together with the ternary complexes show that, contrary to replicative DNA polymerases, the DNA, and not the polymerase, undergoes the primary substrate-induced conformational change. The incoming dNTP "pushes" templates A and G from the anti to the syn conformation dictated by a rigid hPoliota active site. Together, the structures posit a mechanism for template selection wherein dNTP binding induces a conformational switch in template purines for productive Hoogsteen base pairing.
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Affiliation(s)
- Deepak T Nair
- Structural Biology Program, Department of Physiology and Biophysics, Mount Sinai School of Medicine, Box 1677, 1425 Madison Avenue, New York, New York 10029, USA
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16
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Prakash S, Johnson RE, Prakash L. Eukaryotic translesion synthesis DNA polymerases: specificity of structure and function. Annu Rev Biochem 2005; 74:317-53. [PMID: 15952890 DOI: 10.1146/annurev.biochem.74.082803.133250] [Citation(s) in RCA: 789] [Impact Index Per Article: 41.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
This review focuses on eukaryotic translesion synthesis (TLS) DNA polymerases, and the emphasis is on Saccharomyces cerevisiae and human Y-family polymerases (Pols) eta, iota, kappa, and Rev1, as well as on Polzeta, which is a member of the B-family polymerases. The fidelity, mismatch extension ability, and lesion bypass efficiencies of these different polymerases are examined and evaluated in the context of their structures. One major conclusion is that, despite the overall similarity of basic structural features among the Y-family polymerases, there is a high degree of specificity in their lesion bypass properties. Some are able to bypass a particular DNA lesion, whereas others are efficient at only the insertion step or the extension step of lesion bypass. This functional divergence is related to the differences in their structures. Polzeta is a highly specialized polymerase specifically adapted for extending primer termini opposite from a diverse array of DNA lesions, and depending upon the DNA lesion, it contributes to lesion bypass in a mutagenic or in an error-free manner. Proliferating cell nuclear antigen (PCNA) provides the central scaffold to which TLS polymerases bind for access to the replication ensemble stalled at a lesion site, and Rad6-Rad18-dependent protein ubiquitination is important for polymerase exchange.
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Affiliation(s)
- Satya Prakash
- Sealy Center for Molecular Science, University of Texas Medical Branch, Galveston, Texas 77555-1061, USA.
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17
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Wang L, Wu M, Yan SF, Patel DJ, Geacintov NE, Broyde S. Accommodation of a 1S-(-)-benzo[c]phenanthrenyl-N6-dA adduct in the Y-family Dpo4 DNA polymerase active site: structural insights through molecular dynamics simulations. Chem Res Toxicol 2005; 18:441-56. [PMID: 15777084 PMCID: PMC4696753 DOI: 10.1021/tx049786v] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Molecular modeling and molecular dynamics simulations have been performed to elucidate feasible structures in the Y-family Dpo4 DNA polymerase for the 1S-(-)-trans-anti-B[c]Ph-N6-dA adduct, derived from the fjord region polycyclic aromatic hydrocarbon (PAH) benzo[c]phenanthrene. Three types of models were delineated as follows: an intercalation model, a model with the aromatic ring system in the polymerase major groove open pocket, and a -1 deletion major groove model. All four 2'-deoxyribonucleoside 5'-triphosphates (dNTPs) were considered in the first two cases, and a normal Watson-Crick partner positioned to have skipped the modified template was employed as the incoming dNTP in the -1 deletion case. The trajectories derived from the dynamics simulations were analyzed in detail to evaluate the extents of distortion for each system. Overall, our results suggest that the major groove model is the least distorted, followed by the -1 deletion model, while the intercalation model is perturbed the most. The syn-dGTP and syn-dATP mismatches opposite the lesion are well-accommodated in the major groove model, as is the normal Watson-Crick partner dTTP. The intercalation model appears most likely to impede the polymerase. More broadly, these models look reasonable for other PAH metabolite-derived adducts to adenine with similar 1S stereochemistry. Furthermore, these models suggest how error-prone translesion synthesis by Y-family polymerases might produce mutations that may play a role in the initiation of cancer.
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Affiliation(s)
| | | | | | | | | | - Suse Broyde
- To whom correspondence should be addressed. Tel: 212-998-8231. Fax: 212-995-4015.
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18
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Uljon SN, Johnson RE, Edwards TA, Prakash S, Prakash L, Aggarwal AK. Crystal structure of the catalytic core of human DNA polymerase kappa. Structure 2005; 12:1395-404. [PMID: 15296733 DOI: 10.1016/j.str.2004.05.011] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2004] [Revised: 05/13/2004] [Accepted: 05/20/2004] [Indexed: 10/26/2022]
Abstract
We present the crystal structure of the catalytic core of human DNA polymerase kappa (hPolkappa), the first structure of a human Y-family polymerase. hPolkappa is implicated in the proficient extension of mispaired primer termini on undamaged DNAs, and in the extension step of lesion bypass. The structure reveals a stubby "fingers" subdomain, which despite its small size appears to be tightly restrained with respect to a putative templating base. The structure also reveals a novel "thumb" subdomain that provides a basis for the importance of the N-terminal extension unique to hPolkappa. And, most surprisingly, the structure reveals the polymerase-associated domain (PAD) juxtaposed on the dorsal side of the "palm" subdomain, as opposed to the fingers subdomain. Together, these properties suggest that the hPolkappa active site is constrained at the site of the templating base and incoming nucleotide, but the polymerase is less constrained following translocation of the lesion.
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Affiliation(s)
- Sacha N Uljon
- Structural Biology Program, Department of Physiology and Biophysics, Mount Sinai School of Medicine, Box 1677, 1425 Madison Avenue, New York, New York 10029, USA
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19
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Nair DT, Johnson RE, Prakash S, Prakash L, Aggarwal AK. Replication by human DNA polymerase-iota occurs by Hoogsteen base-pairing. Nature 2004; 430:377-80. [PMID: 15254543 DOI: 10.1038/nature02692] [Citation(s) in RCA: 244] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2004] [Accepted: 05/28/2004] [Indexed: 11/09/2022]
Abstract
Almost all DNA polymerases show a strong preference for incorporating the nucleotide that forms the correct Watson-Crick base pair with the template base. In addition, the catalytic efficiencies with which any given polymerase forms the four possible correct base pairs are roughly the same. Human DNA polymerase-iota (hPoliota), a member of the Y family of DNA polymerases, is an exception to these rules. hPoliota incorporates the correct nucleotide opposite a template adenine with a several hundred to several thousand fold greater efficiency than it incorporates the correct nucleotide opposite a template thymine, whereas its efficiency for correct nucleotide incorporation opposite a template guanine or cytosine is intermediate between these two extremes. Here we present the crystal structure of hPoliota bound to a template primer and an incoming nucleotide. The structure reveals a polymerase that is 'specialized' for Hoogsteen base-pairing, whereby the templating base is driven to the syn conformation. Hoogsteen base-pairing offers a basis for the varied efficiencies and fidelities of hPoliota opposite different template bases, and it provides an elegant mechanism for promoting replication through minor-groove purine adducts that interfere with replication.
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Affiliation(s)
- Deepak T Nair
- Structural Biology Program, Department of Physiology and Biophysics, Mount Sinai School of Medicine, Box 1677, 1425 Madison Avenue, New York, New York 10029, USA
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20
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Trincao J, Johnson RE, Wolfle WT, Escalante CR, Prakash S, Prakash L, Aggarwal AK. Dpo4 is hindered in extending a G.T mismatch by a reverse wobble. Nat Struct Mol Biol 2004; 11:457-62. [PMID: 15077104 DOI: 10.1038/nsmb755] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2003] [Accepted: 02/27/2004] [Indexed: 11/09/2022]
Abstract
The ability or inability of a DNA polymerase to extend a mispair directly affects the establishment of genomic mutations. We report here kinetic analyses of the ability of Dpo4, a Y-family polymerase from Sulfolobus solfataricus, to extend from all mispairs opposite a template G or T. Dpo4 is equally inefficient at extending these mispairs, which include, surprisingly, a G.T mispair expected to conform closely to Watson-Crick geometry. To elucidate the basis of this, we solved the structure of Dpo4 bound to G.T-mispaired primer template in the presence of an incoming nucleotide. As a control, we also determined the structure of Dpo4 bound to a matched A-T base pair at the primer terminus. The structures offer a basis for the low efficiency of Dpo4 in extending a G.T mispair: a reverse wobble that deflects the primer 3'-OH away from the incoming nucleotide.
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Affiliation(s)
- Jose Trincao
- Structural Biology Program, Department of Physiology and Biophysics, Mount Sinai School of Medicine, Box 1677, 1425 Madison Avenue, New York, New York 10029, USA
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