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Hegde PM, Dutta A, Sengupta S, Mitra J, Adhikari S, Tomkinson AE, Li GM, Boldogh I, Hazra TK, Mitra S, Hegde ML. The C-terminal Domain (CTD) of Human DNA Glycosylase NEIL1 Is Required for Forming BERosome Repair Complex with DNA Replication Proteins at the Replicating Genome: DOMINANT NEGATIVE FUNCTION OF THE CTD. J Biol Chem 2015; 290:20919-20933. [PMID: 26134572 DOI: 10.1074/jbc.m115.642918] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Indexed: 12/21/2022] Open
Abstract
The human DNA glycosylase NEIL1 was recently demonstrated to initiate prereplicative base excision repair (BER) of oxidized bases in the replicating genome, thus preventing mutagenic replication. A significant fraction of NEIL1 in cells is present in large cellular complexes containing DNA replication and other repair proteins, as shown by gel filtration. However, how the interaction of NEIL1 affects its recruitment to the replication site for prereplicative repair was not investigated. Here, we show that NEIL1 binarily interacts with the proliferating cell nuclear antigen clamp loader replication factor C, DNA polymerase δ, and DNA ligase I in the absence of DNA via its non-conserved C-terminal domain (CTD); replication factor C interaction results in ∼8-fold stimulation of NEIL1 activity. Disruption of NEIL1 interactions within the BERosome complex, as observed for a NEIL1 deletion mutant (N311) lacking the CTD, not only inhibits complete BER in vitro but also prevents its chromatin association and reduced recruitment at replication foci in S phase cells. This suggests that the interaction of NEIL1 with replication and other BER proteins is required for efficient repair of the replicating genome. Consistently, the CTD polypeptide acts as a dominant negative inhibitor during in vitro repair, and its ectopic expression sensitizes human cells to reactive oxygen species. We conclude that multiple interactions among BER proteins lead to large complexes, which are critical for efficient BER in mammalian cells, and the CTD interaction could be targeted for enhancing drug/radiation sensitivity of tumor cells.
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Affiliation(s)
- Pavana M Hegde
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, Texas 77030
| | - Arijit Dutta
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, Texas 77030; Departments of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas 77555
| | - Shiladitya Sengupta
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, Texas 77030
| | - Joy Mitra
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, Texas 77030
| | - Sanjay Adhikari
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, Texas 77030
| | - Alan E Tomkinson
- Department of Internal Medicine and University of New Mexico Cancer Center, University of New Mexico, Albuquerque, New Mexico 87131
| | - Guo-Min Li
- Department of Toxicology and Cancer Biology and Markey Cancer Center, University of Kentucky College of Medicine, Lexington, Kentucky 40536
| | - Istvan Boldogh
- Departments of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas 77555
| | - Tapas K Hazra
- Departments of Internal Medicine, University of Texas Medical Branch, Galveston, Texas 77555
| | - Sankar Mitra
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, Texas 77030; Departments of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas 77555; Weill Medical College of Cornell University, New York, New York.
| | - Muralidhar L Hegde
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, Texas 77030; Weill Medical College of Cornell University, New York, New York; Houston Methodist Neurological Institute, Houston, Texas 77030.
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2
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Abstract
DNA repair mechanisms are critical for maintaining the integrity of genomic DNA, and their loss is associated with cancer predisposition syndromes. Studies in Saccharomyces cerevisiae have played a central role in elucidating the highly conserved mechanisms that promote eukaryotic genome stability. This review will focus on repair mechanisms that involve excision of a single strand from duplex DNA with the intact, complementary strand serving as a template to fill the resulting gap. These mechanisms are of two general types: those that remove damage from DNA and those that repair errors made during DNA synthesis. The major DNA-damage repair pathways are base excision repair and nucleotide excision repair, which, in the most simple terms, are distinguished by the extent of single-strand DNA removed together with the lesion. Mistakes made by DNA polymerases are corrected by the mismatch repair pathway, which also corrects mismatches generated when single strands of non-identical duplexes are exchanged during homologous recombination. In addition to the true repair pathways, the postreplication repair pathway allows lesions or structural aberrations that block replicative DNA polymerases to be tolerated. There are two bypass mechanisms: an error-free mechanism that involves a switch to an undamaged template for synthesis past the lesion and an error-prone mechanism that utilizes specialized translesion synthesis DNA polymerases to directly synthesize DNA across the lesion. A high level of functional redundancy exists among the pathways that deal with lesions, which minimizes the detrimental effects of endogenous and exogenous DNA damage.
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Chaurasia P, Sen R, Bhaumik SR. Functional analysis of Rad14p, a DNA damage recognition factor in nucleotide excision repair, in regulation of transcription in vivo. J Biol Chem 2012. [PMID: 23188830 DOI: 10.1074/jbc.m112.413716] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Rad14p is a DNA damage recognition factor in nucleotide excision repair. Intriguingly, we show here that Rad14p associates with the promoter of a galactose-inducible GAL1 gene after transcriptional induction in the absence of DNA lesion. Such an association of Rad14p facilitates the recruitment of TBP, TFIIH, and RNA polymerase II to the GAL1 promoter. Furthermore, the association of RNA polymerase II with the GAL1 promoter is significantly decreased in the absence of Rad14p, when the coding sequence was deleted. These results support the role of Rad14p in transcriptional initiation. Consistently, the level of GAL1 mRNA is significantly decreased in the absence of Rad14p. Similar results are also obtained at other galactose-inducible GAL genes such as GAL7 and GAL10. Likewise, Rad14p promotes transcription of other non-GAL genes such as CUP1, CTT1, and STL1 after transcriptional induction. However, the effect of Rad14p on the steady-state levels of transcription of GAL genes or constitutively active genes such as ADH1, PGK1, PYK1, and RPS5 is not observed. Thus, Rad14p promotes initial transcription but does not appear to regulate the steady-state level. Collectively, our results unveil a new role of Rad14p in stimulating transcription in addition to its well-known function in nucleotide excision repair.
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Affiliation(s)
- Priyasri Chaurasia
- Department of Biochemistry and Molecular Biology, Southern Illinois University, School of Medicine, Carbondale, Illinois 62901, USA
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4
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Gillet LCJ, Schärer OD. Molecular mechanisms of mammalian global genome nucleotide excision repair. Chem Rev 2006; 106:253-76. [PMID: 16464005 DOI: 10.1021/cr040483f] [Citation(s) in RCA: 463] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Ludovic C J Gillet
- Institute for Molecular Cancer Research, University of Zürich, Switzerland
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5
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Aboussekhra A, Al-Sharif IS. Homologous recombination is involved in transcription-coupled repair of UV damage in Saccharomyces cerevisiae. EMBO J 2005; 24:1999-2010. [PMID: 15902273 PMCID: PMC1142603 DOI: 10.1038/sj.emboj.7600665] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2004] [Accepted: 04/08/2005] [Indexed: 01/17/2023] Open
Abstract
To efficiently protect the integrity of genetic information, transcription is connected to nucleotide excision repair (NER), which allows preferential repair of the transcribed DNA strands (TS). As yet, the molecular basis of this connection remains elusive in eukaryotic cells. Here we show that, in haploids, the RAD26 gene is essential for the preferential repair of the TS during G1. However, in G2/M phase there is an additional RAD51-dependent process that enhances repair of TS. Importantly, the simultaneous deletion of both RAD26 and RAD51 led to complete abolishment of strand-specific repair during G2/M, indicating that these genes act through two independent but complementary subpathways. In diploids, however, RAD51 is involved in repair of the TS even in G1 phase, which unveils the implication of homologous recombination in the preferential repair of the TS. Importantly, the abolishment of NER, by abrogation of RAD1 or RAD14, completely stopped repair of UV damage even during G2/M phase. These results show the existence of functional cross-talk between transcription, homologous recombination and NER.
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Affiliation(s)
- Abdelilah Aboussekhra
- Department of Biological and Medical Research, King Faisal Specialist Hospital & Research Center, Riyadh, Saudi Arabia.
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6
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Ramsey KL, Smith JJ, Dasgupta A, Maqani N, Grant P, Auble DT. The NEF4 complex regulates Rad4 levels and utilizes Snf2/Swi2-related ATPase activity for nucleotide excision repair. Mol Cell Biol 2004; 24:6362-78. [PMID: 15226437 PMCID: PMC434245 DOI: 10.1128/mcb.24.14.6362-6378.2004] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Nucleotide excision repair factor 4 (NEF4) is required for repair of nontranscribed DNA in Saccharomyces cerevisiae. Rad7 and the Snf2/Swi2-related ATPase Rad16 are NEF4 subunits. We report previously unrecognized similarity between Rad7 and F-box proteins. Rad16 contains a RING domain embedded within its ATPase domain, and the presence of these motifs in NEF4 suggested that NEF4 functions as both an ATPase and an E3 ubiquitin ligase. Mutational analysis provides strong support for this model. The Rad16 ATPase is important for NEF4 function in vivo, and genetic analysis uncovered new interactions between NEF4 and Rad23, a repair factor that links repair to proteasome function. Elc1 is the yeast homologue of a mammalian E3 subunit, and it is a novel component of NEF4. Moreover, the E2s Ubc9 and Ubc13 were linked to the NEF4 repair pathway by genetic criteria. Mutations in NEF4 or Ubc13 result in elevated levels of the DNA damage recognition protein Rad4 and an increase in ubiquitylated species of Rad23. As Rad23 also controls Rad4 levels, these results suggest a complex system for globally regulating repair activity in vivo by controlling turnover of Rad4.
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Affiliation(s)
- Kerrington L Ramsey
- Department of Biochemistry and Molecular Genetics, University of Virginia Health System, Charlottesville, VA 22908-0733, USA
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Reardon JT, Sancar A. Molecular anatomy of the human excision nuclease assembled at sites of DNA damage. Mol Cell Biol 2002; 22:5938-45. [PMID: 12138203 PMCID: PMC133982 DOI: 10.1128/mcb.22.16.5938-5945.2002] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2002] [Revised: 05/20/2002] [Accepted: 05/23/2002] [Indexed: 11/20/2022] Open
Abstract
Human nucleotide excision repair is initiated by six repair factors (XPA, RPA, XPC-HR23B, TFIIH, XPF-ERCC1, and XPG) which sequentially assemble at sites of DNA damage and effect excision of damage-containing oligonucleotides. We here describe the molecular anatomy of the human excision nuclease assembled at the site of a psoralen-adducted thymine. Three polypeptides, primarily positioned 5' to the damage, are in close physical proximity to the psoralen lesion and thus are cross-linked to the damaged DNA: these proteins are RPA70, RPA32, and the XPD subunit of TFIIH. While both XPA and XPC bind damaged DNA and are required for XPD cross-linking to the psoralen-adducted base, neither XPA nor XPC is cross-linked to the psoralen adduct. The presence of other repair factors, in particular TFIIH, alters the mode of RPA binding and the position of its subunits relative to the psoralen lesion. Based on these results, we propose that RPA70 makes the initial contact with psoralen-damaged DNA but that within preincision complexes, it is RPA32 and XPD that are in close contact with the lesion.
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Affiliation(s)
- Joyce T Reardon
- Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599,USA
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8
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Abstract
Several types of helix-distorting DNA lesions block the passage of elongating RNA polymerase II. Surprisingly, such transcription-blocking lesions are usually repaired considerably faster than non-obstructive lesions in the non-transcribed strand or in the genome overall. In this review, our knowledge of eukaryotic transcription-coupled repair (TCR) will be considered from the point of view of transcription, and current models for the mechanism of TCR will be discussed.
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Affiliation(s)
- Jesper Q Svejstrup
- Imperial Cancer Research Fund, Clare Hall Laboratories, Blanche Lane, South Mimms, Hertfordshire EN6 3LD, UK.
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9
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Abstract
Eukaryotic cells can repair many types of DNA damage. Among the known DNA repair processes in humans, one type--nucleotide excision repair (NER)--specifically protects against mutations caused indirectly by environmental carcinogens. Humans with a hereditary defect in NER suffer from xeroderma pigmentosum and have a marked predisposition to skin cancer caused by sunlight exposure. How does NER protect against skin cancer and possibly other types of environmentally induced cancer in humans?
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Affiliation(s)
- E C Friedberg
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas 75390-9072, USA.
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10
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Araújo SJ, Nigg EA, Wood RD. Strong functional interactions of TFIIH with XPC and XPG in human DNA nucleotide excision repair, without a preassembled repairosome. Mol Cell Biol 2001; 21:2281-91. [PMID: 11259578 PMCID: PMC86862 DOI: 10.1128/mcb.21.7.2281-2291.2001] [Citation(s) in RCA: 140] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In mammalian cells, the core factors involved in the damage recognition and incision steps of DNA nucleotide excision repair are XPA, TFIIH complex, XPC-HR23B, replication protein A (RPA), XPG, and ERCC1-XPF. Many interactions between these components have been detected, using different physical methods, in human cells and for the homologous factors in Saccharomyces cerevisiae. Several human nucleotide excision repair (NER) complexes, including a high-molecular-mass repairosome complex, have been proposed. However, there have been no measurements of activity of any mammalian NER protein complex isolated under native conditions. In order to assess relative strengths of interactions between NER factors, we captured TFIIH from cell extracts with an anti-cdk7 antibody, retaining TFIIH in active form attached to magnetic beads. Coimmunoprecipitation of other NER proteins was then monitored functionally in a reconstituted repair system with purified proteins. We found that all detectable TFIIH in gently prepared human cell extracts was present in the intact nine-subunit form. There was no evidence for a repair complex that contained all of the NER components. At low ionic strength TFIIH could associate with functional amounts of each NER factor except RPA. At physiological ionic strength, TFIIH associated with significant amounts of XPC-HR23B and XPG but not other repair factors. The strongest interaction was between TFIIH and XPC-HR23B, indicating a coupled role of these proteins in early steps of repair. A panel of antibodies was used to estimate that there are on the order of 10(5) molecules of each core NER factor per HeLa cell.
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Affiliation(s)
- S J Araújo
- Imperial Cancer Research Fund, Clare Hall Laboratories, South Mimms, Hertfordshire EN6 3LD, United Kingdom
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11
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Friedberg EC. Rous-Whipple Award Lecture. Nucleotide excision repair and cancer predisposition: A journey from man to yeast to mice. THE AMERICAN JOURNAL OF PATHOLOGY 2000; 157:693-701. [PMID: 10980107 PMCID: PMC1885695 DOI: 10.1016/s0002-9440(10)64581-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 05/18/2000] [Indexed: 01/21/2023]
Affiliation(s)
- E C Friedberg
- Laboratory of Molecular Pathology, Department of Pathology, The University of Texas Southwestern Medical Center, Dallas, Texas 75390-9072, USA.
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12
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Batty D, Rapic'-Otrin V, Levine AS, Wood RD. Stable binding of human XPC complex to irradiated DNA confers strong discrimination for damaged sites. J Mol Biol 2000; 300:275-90. [PMID: 10873465 DOI: 10.1006/jmbi.2000.3857] [Citation(s) in RCA: 175] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Nucleotide excision repair (NER) of DNA damage requires an efficient means of discrimination between damaged and non-damaged DNA. Cells from humans with xeroderma pigmentosum group C do not perform NER in the bulk of the genome and are corrected by XPC protein, which forms a complex with hHR23B protein. This complex preferentially binds to some types of damaged DNA, but the extent of discrimination in comparison to other NER proteins has not been clear. Recombinant XPC, hHR23B, and XPC-hHR23B complex were purified. In a reconstituted repair system, hHR23B stimulated XPC activity tenfold. Electrophoretic mobility-shift competition measurements revealed a 400-fold preference for binding of XPC-hHR23B to UV damaged over non-damaged DNA. This damage preference is much greater than displayed by the XPA protein. The discrimination power is similar to that determined here in parallel for the XP-E factor UV-DDB, despite the considerably greater molar affinity of UV-DDB for DNA. Binding of XPC-hHR23B to UV damaged DNA was very fast. Damaged DNA-XPC-hHR23B complexes were stable, with half of the complexes remaining four hours after challenge with excess UV-damaged DNA at 30 degrees C. XPC-hHR23B had a higher level of affinity for (6-4) photoproducts than cyclobutane pyrimidine dimers, and some affinity for DNA treated with cisplatin and alkylating agents. XPC-hHR23B could bind to single-stranded M13 DNA, but only poorly to single-stranded homopolymers. The strong preference of XPC complex for structures in damaged duplex DNA indicates its importance as a primary damage recognition factor in non-transcribed DNA during human NER.
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Affiliation(s)
- D Batty
- Imperial Cancer Research Fund, Clare Hall Laboratories, South Mimms, Hertfordshire EN6 3LD, UK
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13
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Feaver WJ, Huang W, Gileadi O, Myers L, Gustafsson CM, Kornberg RD, Friedberg EC. Subunit interactions in yeast transcription/repair factor TFIIH. Requirement for Tfb3 subunit in nucleotide excision repair. J Biol Chem 2000; 275:5941-6. [PMID: 10681587 DOI: 10.1074/jbc.275.8.5941] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A yeast strain harboring a temperature-sensitive allele of TFB3 (tfb3(ts)), the 38-kDa subunit of the RNA polymerase II transcription/nucleotide excision repair factor TFIIH, was found to be sensitive to ultraviolet (UV) radiation and defective for nucleotide excision repair in vitro. Interestingly, tfb3(ts) failed to grow on medium containing caffeine. A comprehensive pairwise two-hybrid analysis between yeast TFIIH subunits identified novel interactions between Rad3 and Tfb3, Tfb4 and Ssl1, as well as Ssl2 and Tfb2. These interactions have facilitated a more complete model of the structure of TFIIH and the nucleotide excision repairosome.
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Affiliation(s)
- W J Feaver
- Laboratory of Molecular Pathology, Department of Pathology, University of Texas Southwestern Medical Center, Dallas, Texas 75235-9072, USA
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14
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Abstract
The main pathway by which mammalian cells remove DNA damage caused by UV light and some other mutagens is nucleotide excision repair (NER). The best characterised components of the human NER process are those proteins defective in the inherited disorder xeroderma pigmentosum (XP). The proteins known to be involved in the first steps of the NER reaction (damage recognition and incision-excision) are heterotrimeric RPA, XPA, the 6 to 9 subunit TFIIH, XPC-hHR23B, XPG, and ERCC1-XPF. Many interactions between these proteins have been found in recent years using different methods both in mammalian cells and for the homologous proteins in yeast. There are virtually no quantitative measurements of the relative strengths of these interactions. Higher order associations between these proteins in solution and even the existence of a complete "repairosome" complex have been reported, which would have implications both for the mechanism of repair and for the interplay between NER and other cellular processes. Nevertheless, evidence for a completely pre-assembled functional repairosome in solution is inconclusive and the order of action of repair factors on damaged DNA is uncertain.
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Affiliation(s)
- S J Araújo
- Imperial Cancer Research Fund, Clare Hall Laboratories, South Mimms, Hertfordshire, UK
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15
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Abstract
Human excision nuclease removes DNA damage by concerted dual incisions bracketing the lesion. The dual incisions are accomplished by sequential and partly overlapping actions of six repair factors, RPA, XPA, XPC, TFIIH, XPG, and XPF.ERCC1. Of these, RPA, XPA, and XPC have specific binding affinity for damaged DNA. To learn about the role of these three proteins in damage recognition and the order of assembly of the excision nuclease, we measured the binding affinities of XPA, RPA, and XPC to a DNA fragment containing a single (6-4) photoproduct and determined the rate of damage excision under a variety of reaction conditions. We found that XPC has the highest affinity to DNA and that RPA has the highest selectivity for damaged DNA. Under experimental conditions conducive to binding of either XPA + RPA or XPC to damaged DNA, the rate of damage removal was about 5-fold faster for reactions in which XPA + RPA was the first damage recognition factor presented to DNA compared with reactions in which XPC was the first protein that had the opportunity to bind to DNA. We conclude that RPA and XPA are the initial damage sensing factors of human excision nuclease.
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Affiliation(s)
- M Wakasugi
- Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599-7260, USA
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Wu X, Braithwaite E, Wang Z. DNA ligation during excision repair in yeast cell-free extracts is specifically catalyzed by the CDC9 gene product. Biochemistry 1999; 38:2628-35. [PMID: 10052932 DOI: 10.1021/bi982592s] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Excision repair of DNA is an important cellular response to DNA damage induced by radiation and many chemicals. In eukaryotes, base excision repair (BER) and nucleotide excision repair (NER) are two major excision repair pathways which are completed by a DNA ligation step. Using a cell-free system, we have determined the DNA ligase requirement during BER and NER of the yeast S. cerevisiae. Under nonpermissive conditions in extracts of the cdc9-2 temperature-sensitive mutant, DNA ligation in both BER and NER pathways was defective, and the repair patches were enlarged. At the permissive temperature (23 degrees C), DNA ligation during excision repair was only partially functional in the mutant extracts. In contrast, deleting the DNA ligase IV gene did not affect DNA ligation of BER or NER. Defective DNA ligation of BER and NER in cdc9-2 mutant extracts was complemented in vitro by purified yeast Cdc9 protein, but not by DNA ligase IV even when overexpressed. These results demonstrate that the ligation step of excision repair in yeast cell-free extracts is catalyzed specifically by the Cdc9 protein, the homologue of mammalian DNA ligase I.
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Affiliation(s)
- X Wu
- Graduate Center for Toxicology, University of Kentucky, Lexington 40536, USA
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17
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You Z, Feaver WJ, Friedberg EC. Yeast RNA polymerase II transcription in vitro is inhibited in the presence of nucleotide excision repair: complementation of inhibition by Holo-TFIIH and requirement for RAD26. Mol Cell Biol 1998; 18:2668-76. [PMID: 9566886 PMCID: PMC110646 DOI: 10.1128/mcb.18.5.2668] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The Saccharomyces cerevisiae transcription factor IIH (TFIIH) is essential both for transcription by RNA polymerase II (RNAP II) and for nucleotide excision repair (NER) of damaged DNA. We have established cell extracts which support RNAP II transcription from the yeast CYC1 promoter or NER of transcriptionally silent damaged DNA on independent plasmid templates and substrates. When plasmid templates and substrates for both processes are simultaneously incubated with these extracts, transcription is significantly inhibited. This inhibition is strictly dependent on active NER and can be complemented with purified holo-TFIIH. These results suggest that in the presence of active NER, TFIIH is preferentially mobilized from the basal transcription machinery for use in NER. Inhibition of transcription in the presence of active NER requires the RAD26 gene, the yeast homolog of the human Cockayne syndrome group B gene (CSB).
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Affiliation(s)
- Z You
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas 75235, USA
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