1
|
Chakalova L, Russev G. Transcriptionally active and inactive mouse beta-globin gene loci are repaired at similar rates after ultraviolet irradiation. EUROPEAN JOURNAL OF BIOCHEMISTRY 1999; 261:667-73. [PMID: 10215882 DOI: 10.1046/j.1432-1327.1999.00332.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
It has been demonstrated, by Northern blot and in situ hybridization, that the mouse erythroleukaemia cell line F4N-Sofia constitutively expresses the beta-globin genes. The recently developed quantitative assay for DNA repair has been used to study the overall repair rate in the beta-globin gene domain in this cell line after ultraviolet irradiation and to compare it with the repair rate of the same chromatin domain in mouse Ehrlich ascites tumour cells which do not express the beta-globin genes. The results showed that in both cases the 5'-end of the domain was repaired preferentially and that the repair rates in the two cell lines were very similar despite the different transcription state of the genes.
Collapse
Affiliation(s)
- L Chakalova
- Institute of Molecular Biology, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | | |
Collapse
|
2
|
Prosperi E. Multiple roles of the proliferating cell nuclear antigen: DNA replication, repair and cell cycle control. PROGRESS IN CELL CYCLE RESEARCH 1998; 3:193-210. [PMID: 9552415 DOI: 10.1007/978-1-4615-5371-7_15] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The proliferating cell nuclear antigen (PCNA), the auxiliary protein of DNA polymerase delta and epsilon, is involved in DNA replication and repair. This protein forms a homotrimeric structure which, encircling DNA, loads the polymerase on the DNA template. A role for PCNA in the cell cycle control is recognised on the basis of the interaction with cyclins, cyclin-dependent kinases (cdks) and the cdk-inhibitor p21 waf1/cip1/sdi1 protein. Association with the growth-arrest and DNA-damage inducible proteins gadd45 and MyD118, further demonstrates the role of PCNA as a component of the cell cycle control apparatus.
Collapse
Affiliation(s)
- E Prosperi
- Dipartimento di Biologia Animale, Università di Pavia, Italy
| |
Collapse
|
3
|
Clarke DJ, Giménez-Abián JF, Tönnies H, Neitzel H, Sperling K, Downes CS, Johnson RT. Creation of monosomic derivatives of human cultured cell lines. Proc Natl Acad Sci U S A 1998; 95:167-71. [PMID: 9419347 PMCID: PMC18162 DOI: 10.1073/pnas.95.1.167] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Monosomic mammalian cell lines would be ideal for studying gene dosage effects, including gene imprinting, and for systematic isolation of recessive somatic mutants parallel to the invaluable mutants derived from haploid yeast. But autosomal monosomies are lethal in early development; although monosomies appear in tumors, deriving cell lines from these tumors is difficult and cannot provide several syngenic lines. We have developed a strategy for generating stable monosomic human cells, based on random autosomal integration of the gpt plasmid, partial inhibition of DNA topoisomerase II during mitosis to promote chromatid nondisjunction, and selection against retention of gpt. These are likely to be valuable as a source of otherwise inaccessible mutants. The strategy can also be used to generate partial mammalian monosomies, which are desirable as a source of information on recessive genes and gene imprinting.
Collapse
Affiliation(s)
- D J Clarke
- Cancer Research Campaign Mammalian Cell DNA Repair Research Group, Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, United Kingdom
| | | | | | | | | | | | | |
Collapse
|
4
|
|
5
|
Affiliation(s)
- M Hall
- Cancer Research Campaign Mammalian Cell DNA Repair Group, Department of Zoology, Cambridge, U.K
| | | |
Collapse
|
6
|
Francino MP, Chao L, Riley MA, Ochman H. Asymmetries generated by transcription-coupled repair in enterobacterial genes. Science 1996; 272:107-9. [PMID: 8600517 DOI: 10.1126/science.272.5258.107] [Citation(s) in RCA: 100] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Although certain replication errors occur at different frequencies on each of the complementary strands of DNA, it remains unclear whether this bias is prevalent enough during chromosome replication to affect sequence evolution. Here, nucleotide substitutions in enteric bacteria were examined, and no difference in mutation rates was detected between the leading and lagging strands, but in comparing the coding and noncoding strands, and excess of C-->T changes was observed on the coding strand. This asymmetry is best explained by transcription-coupled repair on the noncoding strand. Although the vast majority of mutations are thought to arise from spontaneous errors during replication, this result implicates DNA damage as a substantial source of mutations in the wild.
Collapse
Affiliation(s)
- M P Francino
- Department of Biology, University of Rochester, NY 14627, USA
| | | | | | | |
Collapse
|
7
|
Abstract
The formation of DNA photoproducts by ultraviolet (UV) light is responsible for induction of mutations and development of skin cancer. To understand UV mutagenesis, it is important to know the mechanisms of formation and repair of these lesions. Cyclobutane pyrimidine dimers and (6-4)photoproducts are the two major classes of UV-induced DNA lesions. Their distribution along DNA sequences in vivo is strongly influenced by nucleosomes and other DNA binding proteins. Repair of UV photoproducts is dependent on the transcriptional status of the sequences to be repaired and on the chromatin environment. Sensitive techniques are now available to study repair of UV damage at the level of nucleotide resolution in mammalian cells. With the aid of in vitro systems, the entire nucleotide excision repair process has been reconstituted from purified protein components with naked DNA as a substrate. Future work will focus on the development of in vitro assays for transcription-coupled repair and repair in chromatin.
Collapse
Affiliation(s)
- S Tornaletti
- Department of Biology, Beckman Research Institute of the City of Hope, Duarte, CA 91010, USA
| | | |
Collapse
|
8
|
Coates PJ, Save V, Ansari B, Hall PA. Demonstration of DNA damage/repair in individual cells using in situ end labelling: association of p53 with sites of DNA damage. J Pathol 1995; 176:19-26. [PMID: 7542331 DOI: 10.1002/path.1711760105] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
We describe the development and application of in situ end labelling (ISEL) to identity sites of damaged DNA in the nuclei of individual cells. In cell culture, exposure to a variety of genotoxic agents induced a dose and time-dependent increase in nuclear labelling. In addition, examination of histological sections of human skin exposed to solar-stimulated UV light showed ISEL in both keratinocytes and superficial dermal cells, with the same spatial and temporal distribution as that of a marker of DNA repair, PCNA (proliferating cell nuclear antigen). Using co-localization techniques and confocal microscopy, we found increased levels of p53 in many ISEL-positive cells in vitro, with a similar distribution of labelling in the nucleus. This observation provides further evidence for a direct role of p53 in the recognition of damaged DNA. Thus, ISEL should prove a convenient method for demonstrating genotoxic insult in individual cells and in histological material, and may have value in toxicological screening. This high-resolution microscopy technique can also be used to compare the spatial distribution of various proteins implicated in the response to DNA damage with the sites of the lesion.
Collapse
Affiliation(s)
- P J Coates
- Department of Pathology, Ninewells Hospital and Medical School, University of Dundee, U.K
| | | | | | | |
Collapse
|
9
|
McCready S. Repair of 6-4 photoproducts and cyclobutane pyrimidine dimers in rad mutants of Saccharomyces cerevisiae. Mutat Res 1994; 315:261-73. [PMID: 7526203 DOI: 10.1016/0921-8777(94)90037-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Repair rates of both pyrimidine-pyrimidone (6-4) photoproducts and cyclobutane pyrimidine dimers have been measured in the UV-sensitive mutants of Saccharomyces cerevisiae: rad1 to rad12 and rad14 to rad24. A dot blot immunoassay for UV photoproducts was used which measures lesions in the genome as a whole and which distinguishes 6-4 photoproducts from cyclobutane dimers. The principal findings are: (1) Wild-type yeast cells, like normal mammalian cells, repair 6-4 photoproducts more rapidly than cyclobutane dimers. (2) All mutants that are defective in repair are defective in repair of both lesions. (3) The most sensitive alleles of rad1, rad2, rad3, rad4 and rad10 show no repair of either lesion. (4) Leaky alleles of rad1, rad3 and rad14 show a very marked difference in repair rates of the two lesions, rather like the human XPA revertant cell line XP129 and the Chinese hamster mutants UV61 and V-H1. (5) No mutant repairs cyclobutane dimers more rapidly than 6-4 photoproducts.
Collapse
Affiliation(s)
- S McCready
- Department of Biochemistry, University of Oxford, UK
| |
Collapse
|
10
|
The RAD7 and RAD16 genes, which are essential for pyrimidine dimer removal from the silent mating type loci, are also required for repair of the nontranscribed strand of an active gene in Saccharomyces cerevisiae. Mol Cell Biol 1994. [PMID: 8065346 DOI: 10.1128/mcb.14.9.6135] [Citation(s) in RCA: 117] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The rad16 mutant of Saccharomyces cerevisiae was previously shown to be impaired in removal of UV-induced pyrimidine dimers from the silent mating-type loci (D. D. Bang, R. A. Verhage, N. Goosen, J. Brouwer, and P. van de Putte, Nucleic Acids Res. 20:3925-3931, 1992). Here we show that rad7 as well as rad7 rad16 double mutants have the same repair phenotype, indicating that the RAD7 and RAD16 gene products might operate in the same nucleotide excision repair subpathway. Dimer removal from the genome overall is essentially incomplete in these mutants, leaving about 20 to 30% of the DNA unrepaired. Repair analysis of the transcribed RPB2 gene shows that the nontranscribed strand is not repaired at all in rad7 and rad16 mutants, whereas the transcribed strand is repaired in these mutants at a fast rate similar to that in RAD+ cells. When the results obtained with the RPB2 gene can be generalized, the RAD7 and RAD16 proteins not only are essential for repair of silenced regions but also function in repair of nontranscribed strands of active genes in S. cerevisiae. The phenotype of rad7 and rad16 mutants closely resembles that of human xeroderma pigmentosum complementation group C (XP-C) cells, suggesting that RAD7 and RAD16 in S. cerevisiae function in the same pathway as the XPC gene in human cells. RAD4, which on the basis of sequence homology has been proposed to be the yeast XPC counterpart, seems to be involved in repair of both inactive and active yeast DNA, challenging the hypothesis that RAD4 and XPC are functional homologs.
Collapse
|
11
|
Verhage R, Zeeman AM, de Groot N, Gleig F, Bang DD, van de Putte P, Brouwer J. The RAD7 and RAD16 genes, which are essential for pyrimidine dimer removal from the silent mating type loci, are also required for repair of the nontranscribed strand of an active gene in Saccharomyces cerevisiae. Mol Cell Biol 1994; 14:6135-42. [PMID: 8065346 PMCID: PMC359140 DOI: 10.1128/mcb.14.9.6135-6142.1994] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The rad16 mutant of Saccharomyces cerevisiae was previously shown to be impaired in removal of UV-induced pyrimidine dimers from the silent mating-type loci (D. D. Bang, R. A. Verhage, N. Goosen, J. Brouwer, and P. van de Putte, Nucleic Acids Res. 20:3925-3931, 1992). Here we show that rad7 as well as rad7 rad16 double mutants have the same repair phenotype, indicating that the RAD7 and RAD16 gene products might operate in the same nucleotide excision repair subpathway. Dimer removal from the genome overall is essentially incomplete in these mutants, leaving about 20 to 30% of the DNA unrepaired. Repair analysis of the transcribed RPB2 gene shows that the nontranscribed strand is not repaired at all in rad7 and rad16 mutants, whereas the transcribed strand is repaired in these mutants at a fast rate similar to that in RAD+ cells. When the results obtained with the RPB2 gene can be generalized, the RAD7 and RAD16 proteins not only are essential for repair of silenced regions but also function in repair of nontranscribed strands of active genes in S. cerevisiae. The phenotype of rad7 and rad16 mutants closely resembles that of human xeroderma pigmentosum complementation group C (XP-C) cells, suggesting that RAD7 and RAD16 in S. cerevisiae function in the same pathway as the XPC gene in human cells. RAD4, which on the basis of sequence homology has been proposed to be the yeast XPC counterpart, seems to be involved in repair of both inactive and active yeast DNA, challenging the hypothesis that RAD4 and XPC are functional homologs.
Collapse
Affiliation(s)
- R Verhage
- Laboratory of Molecular Genetics, Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, The Netherlands
| | | | | | | | | | | | | |
Collapse
|
12
|
Bardwell AJ, Bardwell L, Wang Z, Siede W, Reagan MS, Tomkinson AE, Friedberg AS, Pittenger C, Feaver WJ, Svejstrup J. Recent insights on DNA repair. The mechanism of damaged nucleotide excision in eukaryotes and its relationship to other cellular processes. Ann N Y Acad Sci 1994; 726:281-91. [PMID: 8092684 DOI: 10.1111/j.1749-6632.1994.tb52829.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- A J Bardwell
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas 75235
| | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Jackson DA, Hassan AB, Errington RJ, Cook PR. Sites in human nuclei where damage induced by ultraviolet light is repaired: localization relative to transcription sites and concentrations of proliferating cell nuclear antigen and the tumour suppressor protein, p53. J Cell Sci 1994; 107 ( Pt 7):1753-60. [PMID: 7983145 DOI: 10.1242/jcs.107.7.1753] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The repair of damage induced in DNA by ultraviolet light involves excision of the damaged sequence and synthesis of new DNA to repair the gap. Sites of such repair synthesis were visualized by incubating permeabilized HeLa or MRC-5 cells with the DNA precursor, biotin-dUTP, in a physiological buffer; then incorporated biotin was immunolabeled with fluorescent antibodies. Repair did not take place at sites that reflected the DNA distribution; rather, sites were focally concentrated in a complex pattern. This pattern changed with time; initially intense repair took place at transcriptionally active sites but when transcription became inhibited it continued at sites with little transcription. Repair synthesis in vitro also occurred in the absence of transcription. Repair sites generally contained a high concentration of proliferating cell nuclear antigen but not the tumour-suppressor protein, p53.
Collapse
Affiliation(s)
- D A Jackson
- CRC Nuclear Structure and Function Research Group, Sir William Dunn School of Pathology, University of Oxford, UK
| | | | | | | |
Collapse
|
14
|
Jackson DA, Balajee AS, Mullenders L, Cook PR. Sites in human nuclei where DNA damaged by ultraviolet light is repaired: visualization and localization relative to the nucleoskeleton. J Cell Sci 1994; 107 ( Pt 7):1745-52. [PMID: 7983144 DOI: 10.1242/jcs.107.7.1745] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The repair of damage induced in DNA by ultraviolet light involves excision of the damage and then repair synthesis to fill the gap. We investigated the sites of repair synthesis using MRC-5 fibroblasts and HeLa cells in G1 phase. Cells were encapsulated in agarose microbeads to protect them during manipulation, irradiated, incubated to allow repair to initiate, and permeabilized with streptolysin O to allow entry of labelled triphosphates; [32P]dTTP was incorporated into acid-insoluble material in a dose-dependent manner. Incubation with biotin-16-dUTP allowed sites of incorporation to be indirectly immunolabeled using a FITC-conjugated antibody; sites were not diffusely spread throughout nuclei but concentrated in discrete foci. This is similar to sites of S phase activity that are attached to an underlying nucleoskeleton. After treatment with an endonuclease, most repaired DNA electroeluted from beads with chromatin fragments; this was unlike nascent DNA made during S phase and suggests that repaired DNA is not as closely associated with the skeleton. However, the procedure destroyed repair activity, so repaired DNA might be attached in vivo through a polymerase that was removed electrophoretically. Therefore this approach cannot be used to determine decisively whether repair sites are associated with a skeleton in vivo.
Collapse
Affiliation(s)
- D A Jackson
- CRC Nuclear Structure and Function Research Group, Sir William Dunn School of Pathology, University of Oxford, UK
| | | | | | | |
Collapse
|
15
|
Sehlmeyer U, Wobus AM. Lower mutation frequencies are induced by ENU in undifferentiated embryonic cells than in differentiated cells of the mouse in vitro. Mutat Res 1994; 324:69-76. [PMID: 7515473 DOI: 10.1016/0165-7992(94)90070-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The pluripotent embryonic carcinoma cells of line P19 established from undifferentiated cells of the early mouse embryo and their differentiated progeny, the epithelioid ectoderm-like EPI-7 cells, were investigated for the induction of mutations at the HPRT locus by the alkylating agent N-ethyl-N-nitrosourea (ENU). We showed that the cytotoxic effects of ENU after a 5-h treatment were lower in undifferentiated P19 cells than in differentiated EPI-7 cells. The IC50 values of ENU in the two cell lines amounted to 0.6 mg/ml and 0.09 mg/ml for P19 and EPI-7 cells, respectively. The induction of 6-thioguanine-resistant mutants by ENU (1.0 mg/ml) determined after an expression time of 8 days for both cell lines resulted in similar mutation frequencies. Using expression times of 8 days for P19 and 11.75 days for EPI-7 cells, taking into account the longer generation time of differentiated EPI-7 cells (13.7 +/- 3.6 h) in comparison to undifferentiated P19 cells (9.3 +/- 0.9 h), ENU induced significantly higher mutant frequencies in EPI-7 cells (4865 mutants/10(6) cells) than in P19 cells (282 mutants/10(6) cells). Our results and data from the literature on UV irradiation-induced repair support the idea that the induction of lower mutation frequencies in embryonic cells may correlate with different proliferation capacities, cell cycle parameters and/or different mechanisms of DNA repair in embryonic stem cells and differentiated cells, respectively.
Collapse
Affiliation(s)
- U Sehlmeyer
- Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany
| | | |
Collapse
|
16
|
Wang Z, Svejstrup JQ, Feaver WJ, Wu X, Kornberg RD, Friedberg EC. Transcription factor b (TFIIH) is required during nucleotide-excision repair in yeast. Nature 1994; 368:74-6. [PMID: 8107888 DOI: 10.1038/368074a0] [Citation(s) in RCA: 128] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Nucleotide-excision repair (NER) is an important cellular defence mechanism against mutagenesis and carcinogenesis. The essential yeast genes RAD3 (ref. 2) and SSL2 (RAD25), homologues of the human xeroderma pigmentosum genes XPD and XPB respectively, have been implicated in NER in yeast. The products of these genes are also subunits of (Rad3 protein) or associate with (Ssl2 protein) purified yeast RNA polymerase II transcription initiation factor b, the counterpart of human TFIIH. Rad3 and Ssl2 proteins may participate directly in NER. Alternatively, they may function exclusively as transcription factors that support NER by influencing the expression of other NER genes. Here we show that defective NER in rad3 mutant extracts can be specifically complemented by purified transcription factor b. Similarly, defective NER in ssl2 mutant extracts is corrected by purified factor b/Ssl2 complex. These results support a direct role of factor b during NER in yeast. Hence, factor b (TFIIH) has a dual role in transcription and NER.
Collapse
Affiliation(s)
- Z Wang
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas 75235
| | | | | | | | | | | |
Collapse
|