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Mandemaker IK, Zhou D, Bruens ST, Dekkers DH, Verschure PJ, Edupuganti RR, Meshorer E, Demmers JAA, Marteijn JA. Histone H1 eviction by the histone chaperone SET reduces cell survival following DNA damage. J Cell Sci 2020; 133:jcs235473. [PMID: 32184266 DOI: 10.1242/jcs.235473] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Accepted: 02/27/2020] [Indexed: 08/31/2023] Open
Abstract
Many chromatin remodeling and modifying proteins are involved in the DNA damage response, where they stimulate repair or induce DNA damage signaling. Interestingly, we identified that downregulation of the histone H1 (H1)-interacting protein SET results in increased resistance to a wide variety of DNA damaging agents. We found that this increased resistance does not result from alleviation of an inhibitory effect of SET on DNA repair but, rather, is the consequence of a suppressed apoptotic response to DNA damage. Furthermore, we provide evidence that the histone chaperone SET is responsible for the eviction of H1 from chromatin. Knockdown of H1 in SET-depleted cells resulted in re-sensitization of cells to DNA damage, suggesting that the increased DNA damage resistance in SET-depleted cells is the result of enhanced retention of H1 on chromatin. Finally, clonogenic survival assays showed that SET and p53 act epistatically in the attenuation of DNA damage-induced cell death. Taken together, our data indicate a role for SET in the DNA damage response as a regulator of cell survival following genotoxic stress.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Imke K Mandemaker
- Erasmus MC, University Medical Center Rotterdam, Department of Molecular Genetics, Oncode Institute, Wytemaweg 80, 3015 CN Rotterdam, The Netherlands
| | - Di Zhou
- Erasmus MC, University Medical Center Rotterdam, Department of Molecular Genetics, Oncode Institute, Wytemaweg 80, 3015 CN Rotterdam, The Netherlands
| | - Serena T Bruens
- Erasmus MC, University Medical Center Rotterdam, Department of Molecular Genetics, Oncode Institute, Wytemaweg 80, 3015 CN Rotterdam, The Netherlands
| | - Dick H Dekkers
- Proteomics Center, Erasmus University Medical Center, 3015 CN Rotterdam, The Netherlands
| | - Pernette J Verschure
- Swammerdam Institute for Life Sciences, University of Amsterdam, 1098 XH Amsterdam, The Netherlands
| | - Raghu R Edupuganti
- The Department of Genetics, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Edmond J. Safra campus, 91904 Jerusalem, Israel
| | - Eran Meshorer
- The Department of Genetics, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Edmond J. Safra campus, 91904 Jerusalem, Israel
- The Edmond and Lily Safra Center for Brain Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Jeroen A A Demmers
- Proteomics Center, Erasmus University Medical Center, 3015 CN Rotterdam, The Netherlands
| | - Jurgen A Marteijn
- Erasmus MC, University Medical Center Rotterdam, Department of Molecular Genetics, Oncode Institute, Wytemaweg 80, 3015 CN Rotterdam, The Netherlands
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2
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Okita K, Yamakawa T, Matsumura Y, Sato Y, Amano N, Watanabe A, Goshima N, Yamanaka S. An Efficient Nonviral Method to Generate Integration-Free Human-Induced Pluripotent Stem Cells from Cord Blood and Peripheral Blood Cells. Stem Cells 2013. [DOI: 10.1002/stem.1293] [Citation(s) in RCA: 503] [Impact Index Per Article: 45.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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3
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Reiss-Sklan E, Levitzki A, Naveh-Many T. The complex regulation of HIC (Human I-mfa domain containing protein) expression. PLoS One 2009; 4:e6152. [PMID: 19582149 PMCID: PMC2701633 DOI: 10.1371/journal.pone.0006152] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2009] [Accepted: 06/08/2009] [Indexed: 11/18/2022] Open
Abstract
Human I-mfa domain containing protein (HIC) differentially regulates transcription from viral promoters. HIC affects the Wnt pathway, the JNK/SAPK pathway and the activity of positive transcription elongation factor-b (P-TEFb). Studies exploring HIC function in mammalian cells used ectopically expressed HIC due to undetected endogenous HIC protein. HIC mRNA contains exceptionally long 5' and 3' untranslated regions (UTRs) compared to the average length of mRNA UTRs. Here we show that HIC protein is subject to strict repression at multiple levels. The HIC mRNA UTRs reduce the expression of HIC or of a reporter protein: The HIC 3'-UTR decreases both HIC and reporter mRNA levels, whereas upstream open reading frames located in the 5'-UTR repress the translation of HIC or of the reporter protein. In addition, ectopically expressed HIC protein is degraded by the proteasome, with a half-life of approximately 1 h, suggesting that upon activation, HIC expression in cells may be transient. The strict regulation of HIC expression at the levels of mRNA stability, translation efficiency and protein stability suggests that expression of the HIC protein and its involvement in the various pathways is required only under specific cellular conditions.
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Affiliation(s)
- Ella Reiss-Sklan
- Department of Biological Chemistry, Institute of Life Science, The Hebrew University, Jerusalem, Israel
| | - Alexander Levitzki
- Department of Biological Chemistry, Institute of Life Science, The Hebrew University, Jerusalem, Israel
| | - Tally Naveh-Many
- Minerva Center for Calcium and Bone Metabolism, Nephrology Services, Hadassah Hebrew University Medical Center, Jerusalem, Israel
- * E-mail:
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4
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Abstract
We performed a functional genetic screen to find novel antiapoptotic genes that are under the regulation of the oncoprotein c-Src. Several clones were identified, including subunit S5a of the 26S proteasome. We found that S5a rescued Saos-2 cells from apoptosis induced by Src inhibitor 4-amino-5-(4-methylphenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine (PP1). S5a mRNA and protein levels were downregulated as a result of Src inhibition, either by siRNA or PP1. In cell lines that possess high activity of Src S5a levels were elevated. Cloning of the S5a promoter region showed that S5a transcription responds to several stimuli. Analysis of the promoter sequence revealed a binding site for Tcf/Lef-1 transcription factor. Indeed, beta-catenin significantly induced transcription from the S5a promoter, whereas EMSA studies showed that Lef-1 binds the S5a promoter-binding site. Furthermore, we also found that PP1 and LY294002, but not PD98059 inhibit the S5a promoter activity. These results suggest that S5a is regulated during apoptosis at the transcriptional level and that S5a upregulation by antiapoptotic signals can contribute to cell survival.
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Affiliation(s)
- Yael Gus
- The Hebrew University, Department of Biological Chemistry, Silberman Institute, Givat Ram, Jerusalem 91904, Israel
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5
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Lerdrup M, Holmberg C, Dietrich N, Shaulian E, Herdegen T, Jäättelä M, Kallunki T. Depletion of the AP-1 repressor JDP2 induces cell death similar to apoptosis. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2005; 1745:29-37. [PMID: 16026868 DOI: 10.1016/j.bbamcr.2005.06.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2004] [Revised: 05/27/2005] [Accepted: 06/01/2005] [Indexed: 01/31/2023]
Abstract
JDP2 is a ubiquitously expressed nuclear protein that efficiently represses the activity of the transcription factor AP-1. Thus far, all studies of JDP2 function have relied on the ectopic expression of the protein. In this study, we use a different approach: depletion of JDP2 from cells. Specific depletion of JDP2 resulted in p53-independent cell death that resembles apoptosis and was evident at 72 h. The death mechanism was caspase dependent as the cells could be rescued by treatment with caspase inhibitor zVAD. Our studies suggest that JDP2 functions as a general survival protein, not only following UV-irradiation, as reported earlier, but also under normal culture conditions. Thus, our data support that JDP2 is a cellular survival protein whose presence is necessary for normal cellular function.
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Affiliation(s)
- M Lerdrup
- Apoptosis Department, Institute of Biological Cancer Research, Danish Cancer Society, Strandboulevarden 49, DK-2100 Copenhagen, Denmark
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6
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Koh EY, Chen T, Daley GQ. Novel retroviral vectors to facilitate expression screens in mammalian cells. Nucleic Acids Res 2002; 30:e142. [PMID: 12490733 PMCID: PMC140091 DOI: 10.1093/nar/gnf142] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
As tools for functional genomics, expression profiling and proteomics provide correlative data, while expression cloning screens can link genes directly to biological function. However, technical limitations of gene transfer, expression, and recovery of candidate genes have limited wider application of genome-wide expression screens. Here we describe the pEYK retroviral vectors, which maintain high titers and robust gene expression while addressing the major bottleneck of expression cloning--efficient candidate gene recovery. By exploiting schemes for enhanced PCR rescue or strategies for direct isolation of proviral DNA as plasmids in bacterial hosts, the pEYK vectors facilitate cDNA isolation from selected cells and enable rapid iteration of screens and genetic reversion analyses to validate gene candidates. These vectors have proven useful to identify genes linked to cell proliferation, senescence and apoptosis.
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Affiliation(s)
- Eugene Y Koh
- Whitehead Institute, Nine Cambridge Center, Cambridge, MA 02142, USA
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7
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Richie CT, Peterson C, Lu T, Hittelman WN, Carpenter PB, Legerski RJ. hSnm1 colocalizes and physically associates with 53BP1 before and after DNA damage. Mol Cell Biol 2002; 22:8635-47. [PMID: 12446782 PMCID: PMC139863 DOI: 10.1128/mcb.22.24.8635-8647.2002] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2002] [Revised: 05/07/2002] [Accepted: 09/19/2002] [Indexed: 11/20/2022] Open
Abstract
snm1 mutants of Saccharomyces cerevisiae have been shown to be specifically sensitive to DNA interstrand crosslinking agents but not sensitive to monofunctional alkylating agents, UV, or ionizing radiation. Five homologs of SNM1 have been identified in the mammalian genome and are termed SNM1, SNM1B, Artemis, ELAC2, and CPSF73. To explore the functional role of human Snm1 in response to DNA damage, we characterized the cellular distribution and dynamics of human Snm1 before and after exposure to DNA-damaging agents. Human Snm1 was found to localize to the cell nucleus in three distinct patterns. A particular cell showed diffuse nuclear staining, multiple nuclear foci, or one or two larger bodies confined to the nucleus. Upon exposure to ionizing radiation or an interstrand crosslinking agent, the number of cells exhibiting Snm1 bodies was reduced, while the population of cells with foci increased dramatically. Indirect immunofluorescence studies also indicated that the human Snm1 protein colocalized with 53BP1 before and after exposure to ionizing radiation, and a physical interaction was confirmed by coimmunoprecipitation assays. Furthermore, human Snm1 foci formed after ionizing radiation were largely coincident with foci formed by human Mre11 and to a lesser extent with those formed by BRCA1, but not with those formed by human Rad51. Finally, we mapped a region of human Snm1 of approximately 220 amino acids that was sufficient for focus formation when attached to a nuclear localization signal. Our results indicate a novel function for human Snm1 in the cellular response to double-strand breaks formed by ionizing radiation.
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Affiliation(s)
- Christopher T Richie
- Department of Molecular Genetics, M. D. Anderson Cancer Center, Houston, Texas 77030, USA
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8
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French CA, Masson JY, Griffin CS, O'Regan P, West SC, Thacker J. Role of mammalian RAD51L2 (RAD51C) in recombination and genetic stability. J Biol Chem 2002; 277:19322-30. [PMID: 11912211 DOI: 10.1074/jbc.m201402200] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The highly conserved RAD51 protein has a central role in homologous recombination. Five novel RAD51-like genes have been identified in mammalian cells, but little is known about their functions. A DNA damage-sensitive hamster cell line, irs3, was found to have a mutation in the RAD51L2 gene and an undetectable level of RAD51L2 protein. Resistance of irs3 to DNA-damaging agents was significantly increased by expression of the human RAD51L2 gene, but not by other RAD51-like genes or RAD51 itself. Consistent with a role for RAD51L2 in homologous recombination, irs3 cells show a reduction in sister chromatid exchange, an increase in isochromatid breaks, and a decrease in damage-dependent RAD51 focus formation compared with wild type cells. As recently demonstrated for human cells, we show that RAD51L2 forms part of two separate complexes of hamster RAD51-like proteins. Strikingly, neither complex of RAD51-like proteins is formed in irs3 cells. Our results demonstrate that RAD51L2 has a key role in mammalian RAD51-dependent processes, contingent on the formation of protein complexes involved in homologous recombination repair.
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Affiliation(s)
- Catherine A French
- Medical Research Council, Radiation & Genome Stability Unit, Harwell, Oxfordshire OX11 0RD, United Kingdom
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9
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Egeblad M, Mortensen OH, Jäättelä M. Truncated ErbB2 receptor enhances ErbB1 signaling and induces reversible, ERK-independent loss of epithelial morphology. Int J Cancer 2001; 94:185-91. [PMID: 11668496 DOI: 10.1002/ijc.1459] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Shedding of the extracellular domain of the ErbB2 tyrosine kinase receptor and expression of the remaining NH(2)-terminally truncated ErbB2 correlates with lymph node metastases and adverse outcome in human breast cancer. To study the possible signaling from such a truncated receptor, MCF-7 human breast cancer cells expressing NH(2)-terminally truncated ErbB2 (DeltaNErbB2) were compared with cells overexpressing wild-type ErbB2. Expression of DeltaNErbB2 in MCF-7 cells resulted in sustained activation of extracellular signal-regulated kinases (ERK) 1/2, extensive loss of the epithelial morphology, appearance of vesicles and long protrusions as well as pronounced scattering of the cells. Similar alterations were observed upon ErbB2 overexpression but at much lower levels. Employing cell clones with inducible expression of DeltaNErbB2, it was revealed that the morphological changes were fully reversible and depended on continuous expression of DeltaNErbB2 but not on the activation of the ERK1/2 pathway. Interestingly, the expression of DeltaNErbB2 resulted also in the increased expression and phosphorylation of ErbB1 as well as in the prolonged ligand-induced activation of the ErbB1 signaling pathway. In conclusion, constitutive signaling upon expression of the truncated ErbB2 receptor in human breast cancer cells promotes morphological changes indicative of a more motile and aggressive phenotype.
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Affiliation(s)
- M Egeblad
- Apoptosis Laboratory, Institute of Cancer Biology, Danish Cancer Society, Denmark
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10
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Van Craenenbroeck K, Vanhoenacker P, Haegeman G. Episomal vectors for gene expression in mammalian cells. EUROPEAN JOURNAL OF BIOCHEMISTRY 2000; 267:5665-78. [PMID: 10971576 DOI: 10.1046/j.1432-1327.2000.01645.x] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
An important reason for preferring mammalian cells for heterologous gene expression is their ability to make authentic proteins containing post-translational modifications similar to those of the native protein. The development of expression systems for mammalian cells has been ongoing for several years, resulting in a wide variety of effective expression vectors. The aim of this review is to highlight episomal expression vectors. Such episomal plasmids are usually based on sequences from DNA viruses, such as BK virus, bovine papilloma virus 1 and Epstein-Barr virus. In this review we will mainly focus on the improvements made towards the usefulness of these systems for gene expression studies and gene therapy.
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11
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Sutherland LC, Edwards SE, Cable HC, Poirier GG, Miller BA, Cooper CS, Williams GT. LUCA-15-encoded sequence variants regulate CD95-mediated apoptosis. Oncogene 2000; 19:3774-81. [PMID: 10949932 DOI: 10.1038/sj.onc.1203720] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Using an expression cloning system to discover novel genes involved in apoptosis, we identified a 326 bp bone marrow cDNA fragment (termed Je2) that suppresses, upon transfection, CD95-mediated apoptosis in Jurkat T cells. Sequence homology revealed that Je2 maps to 3p21.3, to an intronic region of the candidate TSG LUCA-15 locus. It represents, in fact, an antisense transcript to the 3'-UTR of two novel splice variants of this gene. Overexpression of sequence representing one of these splice variants (a 2.6 kb cDNA termed Clone 26), inhibited proliferation of Jurkat cells and sensitized them to CD95-mediated apoptosis. This study therefore implicates the LUCA-15 gene locus in the control of apoptosis.
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Affiliation(s)
- L C Sutherland
- School of Life Sciences, Keele University, Staffordshire, UK
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12
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Egeblad M, Jäättelä M. Cell death induced by TNF or serum starvation is independent of ErbB receptor signaling in MCF-7 breast carcinoma cells. Int J Cancer 2000; 86:617-25. [PMID: 10797281 DOI: 10.1002/(sici)1097-0215(20000601)86:5<617::aid-ijc3>3.0.co;2-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The ErbB receptor tyrosine kinase family consists of the epidermal growth factor (EGF) receptor (ErbB1) and three related receptors (ErbB2, ErbB3, ErbB4). Their intrinsic tyrosine kinases can be activated by receptor-dimerization induced by numerous ligands or overexpression. ErbB receptors are frequently overexpressed in breast cancer, and their overexpression is associated with protection from apoptosis. To directly assess their role in apoptosis sensitivity of breast cancer cells, we established MCF-7 breast carcinoma cell lines overexpressing each ErbB receptor alone or in all possible pairs. Overexpression of ErbB1, ErbB2 and ErbB4 receptors was enough to activate them as judged by their phosphorylation, whereas co-expression of other ErbB receptors was necessary for the phosphorylation of the ErbB3. Surprisingly, overexpression of the ErbB receptors even when combined with treatment with their ligands (EGF, transforming growth factor alpha, betacellulin, neuregulins) failed to protect the MCF-7 cells from cell death induced by either tumor necrosis factor (TNF) or serum starvation. During starvation TGF-alpha, however, increased the cell size of the ErbB1 overexpressing cell line, and neuregulin1-beta1 increased that of all cell lines. In conclusion, our data does not support the role of ErbB receptors in the regulation of cell death induced by TNF or serum starvation, and the observed association in breast cancer may be due to other concomitant changes.
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Affiliation(s)
- M Egeblad
- Apoptosis Laboratory, Institute of Cancer Biology, Danish Cancer Society, Copenhagen, Denmark
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13
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Abstract
Epstein-Barr nuclear antigen 1, or EBNA-1, is required for the replication of the EBV genome as an extra-chromosomal element and is a key transcriptional regulator of this virus's latent gene expression. In this review we will describe the salient features of EBNA-1 and oriP, the latent origin of EBV to which EBNA-1 binds site-specifically. EBNA-1's association with host cellular factors, its association with metaphase chromosomes, and its ability to link DNAs to which it binds will be discussed in relation to its roles in replication and transcriptional activation. Although the mechanisms by which EBNA-1 facilitates replication and transcription largely remain enigmatic, EBV's viral replicon has been exploited successfully for applications in gene therapy and in the design of eukaryotic vectors for use in cell culture.
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Affiliation(s)
- E R Leight
- McArdle Laboratory for Cancer Research, University of Wisconsin Medical School, 1400 University Avenue, Madison, WI 53706, USA
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14
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Tanaka J, Miwa Y, Miyoshi K, Ueno A, Inoue H. Construction of Epstein-Barr virus-based expression vector containing mini-oriP. Biochem Biophys Res Commun 1999; 264:938-43. [PMID: 10544034 DOI: 10.1006/bbrc.1999.1617] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Epstein-Barr virus (EBV)-based vectors are extrachromosomal vectors carrying a replicational origin, oriP (about 2200 bp) and a replication initiation factor (EBNA-1) which are sufficient for autonomous replication. Because one disadvantage of these vectors is their large sizes, we examined the effect of partial deletion of oriP on the effectiveness of the EBV-based vectors, using an enhanced green fluorescent protein (EGFP) as a reporter to monitor gene expression. Results indicated that 954 bp-deleted mini-oriP is useful in primate cells since the vector showed high efficiency of stable transfection, a high ratio of EGFP-positive cells, and high recovery of intact plasmid DNA from transfected cells.
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Affiliation(s)
- J Tanaka
- Department of Biochemistry, School of Dentistry, University of Tokushima, 3-18-15 Kuramoto, Tokushima, 770-8504, Japan
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15
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Affiliation(s)
- D Mackey
- McArdle Laboratory for Cancer Research, University of Wisconsin, Madison 53706, USA
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16
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Kurimasa A, Kumano S, Boubnov NV, Story MD, Tung CS, Peterson SR, Chen DJ. Requirement for the kinase activity of human DNA-dependent protein kinase catalytic subunit in DNA strand break rejoining. Mol Cell Biol 1999; 19:3877-84. [PMID: 10207111 PMCID: PMC84245 DOI: 10.1128/mcb.19.5.3877] [Citation(s) in RCA: 225] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The catalytic subunit of DNA-dependent protein kinase (DNA-PKcs) is an enormous, 470-kDa protein serine/threonine kinase that has homology with members of the phosphatidylinositol (PI) 3-kinase superfamily. This protein contributes to the repair of DNA double-strand breaks (DSBs) by assembling broken ends of DNA molecules in combination with the DNA-binding factors Ku70 and Ku80. It may also serve as a molecular scaffold for recruiting DNA repair factors to DNA strand breaks. This study attempts to better define the role of protein kinase activity in the repair of DNA DSBs. We constructed a contiguous 14-kb human DNA-PKcs cDNA and demonstrated that it can complement the DNA DSB repair defects of two mutant cell lines known to be deficient in DNA-PKcs (M059J and V3). We then created deletion and site-directed mutations within the conserved PI 3-kinase domain of the DNA-PKcs gene to test the importance of protein kinase activity for DSB rejoining. These DNA-PKcs mutant constructs are able to express the protein but fail to complement the DNA DSB or V(D)J recombination defects of DNA-PKcs mutant cells. These results indicate that the protein kinase activity of DNA-PKcs is essential for the rejoining of DNA DSBs in mammalian cells. We have also determined a model structure for the DNA-PKcs kinase domain based on comparisons to the crystallographic structure of a cyclic AMP-dependent protein kinase. This structure gives some insight into which amino acid residues are crucial for the kinase activity in DNA-PKcs.
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Affiliation(s)
- A Kurimasa
- Life Sciences Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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17
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Piret B, Schoonbroodt S, Piette J. The ATM protein is required for sustained activation of NF-kappaB following DNA damage. Oncogene 1999; 18:2261-71. [PMID: 10327072 DOI: 10.1038/sj.onc.1202541] [Citation(s) in RCA: 137] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Cells lacking an intact ATM gene are hypersensitive to ionizing radiation and show multiple defects in the cell cycle-coupled checkpoints. DNA damage usually triggers cell cycle arrest through, among other things, the activation of p53. Another DNA-damage responsive factor is NF-kappaB. It is activated by various stress situations, including oxidative stress, and by DNA-damaging compounds such as topoisomerase poisons. We found that cells from Ataxia Telangiectasia patients exhibit a defect in NF-kappaB activation in response to treatment with camptothecin, a topoisomerase I poison. In AT cells, this activation is shortened or suppressed, compared to that observed in normal cells. Ectopic expression of the ATM protein in AT cells increases the activation of NF-kappaB in response to camptothecin. MO59J glioblastoma cells that do not express the DNA-PK catalytic subunit respond normally to camptothecin. These results support the hypothesis that NF-kappaB is a DNA damage-responsive transcription factor and that its activation pathway by DNA damage shares some components with the one leading to p53 activation.
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Affiliation(s)
- B Piret
- Laboratory of Fundamental Virology and Immunology, University of Liège, CHU, Belgium
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18
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Li L, Peterson CA, Kanter-Smoler G, Wei YF, Ramagli LS, Sunnerhagen P, Siciliano MJ, Legerski RJ. hRAD17, a structural homolog of the Schizosaccharomyces pombe RAD17 cell cycle checkpoint gene, stimulates p53 accumulation. Oncogene 1999; 18:1689-99. [PMID: 10208430 DOI: 10.1038/sj.onc.1202469] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The RAD17 gene product of S. Pombe is an essential component of the checkpoint control pathway which responds to both DNA damage and disruption of replication. We have identified a human cDNA that encodes a polypeptide which is structurally conserved with the S. Pombe Rad17 protein. The human gene, designated hRAD17, predicts an encoded protein of 590 amino acids and a molecular weight of 69 kD. Amino acid sequence alignment revealed that hRadl7 has 28.3% and 52.5% similarity with the S. Pombe Rad17 protein, and 21.8% identity and 45.8% similarity to the budding yeast cell cycle checkpoint protein, Rad 24. When introduced into the S. Pombe rad17 mutant, hRAD17 was able to partially revert its hydroxyurea and ionizing radiation hypersensitivity, but not its UV hypersensitivity. Permanent overexpression of the hRAD17 gene in human fibrosarcoma cells resulted in p53 activation and a significant reduction of S- and G2/M-phase cells accompanied by an accumulation of the G1-phase population, suggesting that hRAD17 may have a role in cell cycle checkpoint control. Immunostaining of HT-1080 cells transiently transfected with a hRAD17 construct confirmed the nuclear accumulation of p53, which mimics the induction caused by DNA damage. Using FISH analysis, we have mapped the hRAD17 locus to human chromosome 5q11.2.
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Affiliation(s)
- L Li
- Department of Experimental Radiation Oncology, University of Texas, MD Anderson Cancer Center, Houston 77030, USA
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19
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Shiloh Y, Bar-Shira A, Galanty Y, Ziv Y. Cloning and expression of large mammalian cDNAs: lessons from ATM. GENETIC ENGINEERING 1998; 20:239-48. [PMID: 9666562 DOI: 10.1007/978-1-4899-1739-3_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Y Shiloh
- Department of Human Genetics, Sackler School of Medicine, Tel Aviv University, Israel
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20
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Cartwright R, Tambini CE, Simpson PJ, Thacker J. The XRCC2 DNA repair gene from human and mouse encodes a novel member of the recA/RAD51 family. Nucleic Acids Res 1998; 26:3084-9. [PMID: 9628903 PMCID: PMC147676 DOI: 10.1093/nar/26.13.3084] [Citation(s) in RCA: 119] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We recently identified a positional candidate for the XRCC2 DNA repair gene at human chromosome 7q36.1. We have now cloned the cDNA for this gene from both human and mouse and show that it is a highly conserved novel member of the recA / RAD51 recombination repair gene family. The cDNA is able to complement significantly the phenotype of a unique cell line, irs1 , which shows extreme sensitivity to DNA cross-linking agents and genetic instability. Thisphenotype is consistent with a role for the XRCC2 gene in recombination repair in somatic cells, suggesting that in addition to RAD51 , other members of this gene family have an important function in high fidelity repair processes in mammals. Despite this function, the XRCC2 gene transcript is expressed at a very low level in somatic tissue, but is elevated in mouse testis, suggesting an additional role in meiosis.
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Affiliation(s)
- R Cartwright
- Medical Research Council, Radiation and Genome Stability Unit, Harwell, Oxfordshire OX11 0RD, UK
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21
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Cartwright R, Dunn AM, Simpson PJ, Tambini CE, Thacker J. Isolation of novel human and mouse genes of the recA/RAD51 recombination-repair gene family. Nucleic Acids Res 1998; 26:1653-9. [PMID: 9512535 PMCID: PMC147465 DOI: 10.1093/nar/26.7.1653] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Genes from the recA/RAD51 family play essential roles in homologous recombination in all organisms. Using sequence homologies from eukaryotic members of this family we have identified fragments of two additional mammalian genes with homology to RAD51. Cloning the full-length cDNAs for both human and mouse genes showed that the sequences are highly conserved, and that the predicted proteins have characteristic features of this gene family. One of the novel genes (R51H2) occurs in two forms in human cDNA, differing extensively at the 3' end, probably due to an unusual form of alternative splicing. The new genes (R51H2 and R51H3) were mapped to human chromosomes 14q23-24 and 17q1.2, respectively. Expression studies showed that R51H2 is expressed at lower levels than R51H3 , but that expression of both genes occurs at elevated levels in the testis compared with other tissues. The combination of gene structure conservation and the transcript expression patterns suggests that these new members of the recA/RAD51 family may also function in homologous recombination-repair pathways.
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Affiliation(s)
- R Cartwright
- Medical Research Council, Radiation and Genome Stability Unit, Harwell, Oxfordshire OX11 0RD, UK
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22
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Dosanjh MK, Collins DW, Fan W, Lennon GG, Albala JS, Shen Z, Schild D. Isolation and characterization of RAD51C, a new human member of the RAD51 family of related genes. Nucleic Acids Res 1998; 26:1179-84. [PMID: 9469824 PMCID: PMC147393 DOI: 10.1093/nar/26.5.1179] [Citation(s) in RCA: 135] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The yeast and human RAD51 genes encode strand-transfer proteins that are thought to be involved in both recombinational repair of DNA damage and meiotic recombination. In yeast, the Rad51 family of related proteins also includes Rad55, Rad57 and Dmc1. In mammalian cells, five genes in this family have been identified (HsRAD51, XRCC2, XRCC3, RAD51B/hREC2 and HsDMC1), and here we report the isolation of the sixth member, RAD51C. RAD51C was originally identified by a computer screen of the EST database. A full-length approximately 1.3 kb cDNA clone has been isolated that encodes a protein of 376 aa, having a 18-26% aa identity with other human Rad51 family members. RAD51C includes a previously mapped sequenced-tagged site location near the end of chromosome 17q. The RAD51C transcript is expressed in various human tissues, with highest level of expression in testis, followed by heart muscle, spleen and prostate. Yeast two-hybrid experiments indicate that the Rad51C protein binds to two other members of the Rad51 protein family (Xrcc3 and Rad51B) but not to itself. These findings suggest that Rad51C may function similarly to the yeast Rad55 or Rad57 proteins, rather than as a Rad51 functional homolog.
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Affiliation(s)
- M K Dosanjh
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
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23
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Abstract
XP group C protein (XPC) and a human homologue of RAD23, HHR23B, have previously been shown to copurify in a tightly associated complex. Here, we show that XPC interacts in vivo, by means of the yeast two-hybrid system, with both HHR23B and a second homologue of RAD23, HHR23A. Domain mapping studies have revealed that both RAD23 homologues interact with XPC at the same highly conserved region in the C-terminal half of the protein. XPC mutants deleted within this domain and that are highly deficient in binding both RAD23 homologues are also highly defective in complementing XPC cells in vivo. Domain mapping studies have also identified a region in the N-terminal half of HHR23B that contains the XPC interactive site. This domain is highly conserved among HHR23B, HHR23A, and RAD23.
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Affiliation(s)
- L Li
- Department of Molecular Genetics, University of Texas M.D. Anderson Cancer Center, Houston 77030, USA
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24
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Simpson K, Huxley C. A shuttle system for transfer of YACs between yeast and mammalian cells. Nucleic Acids Res 1996; 24:4693-9. [PMID: 8972855 PMCID: PMC146308 DOI: 10.1093/nar/24.23.4693] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The development of a system for shuttling DNA cloned as yeast artificial chromosomes (YACs) between yeast and mammalian cells requires that the DNA is maintained as extrachromosomal elements in both cell types. We have recently shown that circular YACs carrying the Epstein-Barr virus origin of plasmid replication (oriP) are maintained as stable, episomal elements in a human kidney cell line constitutively expressing the viral transactivator protein EBNA-1. Here, we demonstrate that a 90-kb episomal YAC can be isolated intact from human cells by a simple alkaline lysis procedure and shuttled back into Saccharomyces cerevisiae by spheroplast transformation. In addition, we demonstrate that the 90-kb YAC can be isolated intact from yeast cells. The ability to shuttle large, intact fragments of DNA between yeast and human cells should provide a powerful tool in the manipulation and analysis of functional regions of mammalian DNA.
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Affiliation(s)
- K Simpson
- Department of Biochemistry and Molecular Genetics, Imperial College School of Medicine at St. Mary's, London, UK
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25
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Brookman KW, Lamerdin JE, Thelen MP, Hwang M, Reardon JT, Sancar A, Zhou ZQ, Walter CA, Parris CN, Thompson LH. ERCC4 (XPF) encodes a human nucleotide excision repair protein with eukaryotic recombination homologs. Mol Cell Biol 1996; 16:6553-62. [PMID: 8887684 PMCID: PMC231657 DOI: 10.1128/mcb.16.11.6553] [Citation(s) in RCA: 96] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
ERCC4 is an essential human gene in the nucleotide excision repair (NER) pathway, which is responsible for removing UV-C photoproducts and bulky adducts from DNA. Among the NER genes, ERCC4 and ERCC1 are also uniquely involved in removing DNA interstrand cross-linking damage. The ERCC1-ERCC4 heterodimer, like the homologous Rad10-Rad1 complex, was recently found to possess an endonucleolytic activity that incises on the 5' side of damage. The ERCC4 gene, assigned to chromosome 16p13.1-p13.2, was previously isolated by using a chromosome 16 cosmid library. It corrects the defect in Chinese hamster ovary (CHO) mutants of NER complementation group 4 and is implicated in complementation group F of the human disorder xeroderma pigmentosum. We describe the ERCC4 gene structure and functional cDNA sequence encoding a 916-amino-acid protein (104 kDa), which has substantial homology with the eukaryotic DNA repair and recombination proteins MEI-9 (Drosophila melanogaster), Rad16 (Schizosaccharomyces pombe), and Rad1 (Saccharomyces cerevisiae). ERCC4 cDNA efficiently corrected mutants in rodent NER complementation groups 4 and 11, showing the equivalence of these groups, and ERCC4 protein levels were reduced in mutants of both groups. In cells of an XP-F patient, the ERCC4 protein level was reduced to less than 5%, consistent with XPF being the ERCC4 gene. The considerable identity (40%) between ERCC4 and MEI-9 suggests a possible involvement of ERCC4 in meiosis. In baboon tissues, ERCC4 was expressed weakly and was not significantly higher in testis than in nonmeiotic tissues.
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Affiliation(s)
- K W Brookman
- Biology and Biotechnology Research Program, Lawrence Livermore National Laboratory, Livermore, California 94551-0808, USA
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26
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Simpson K, McGuigan A, Huxley C. Stable episomal maintenance of yeast artificial chromosomes in human cells. Mol Cell Biol 1996; 16:5117-26. [PMID: 8756669 PMCID: PMC231512 DOI: 10.1128/mcb.16.9.5117] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Plasmids carrying the Epstein-Barr virus origin of plasmid replication (oriP) have been shown to replicate autonomously in latently infected human cells (J. Yates, N. Warren, D. Reisman, and B. Sugden, Proc. Natl. Acad. Sci. USA 81:3806-3810, 1984). We demonstrate that addition of this domain is sufficient for stable episomal maintenance of yeast artificial chromosomes (YACs), up to at least 660 kb, in human cells expressing the viral protein EBNA-1. To better approximate the latent viral genome, YACs were circularized before addition of the oriP domain by homologous recombination in yeast cells. The resulting OriPYACs were maintained as extrachromosomal molecules over long periods in selection; a 90-kb OriPYAC was unrearranged in all cell lines analyzed, whereas the intact form of a 660-kb molecule was present in two of three cell lines. The molecules were also relatively stable in the absence of selection. This finding indicates that the oriP-EBNA-1 interaction is sufficient to stabilize episomal molecules of at least 660 kb and that such elements do not undergo rearrangements over time. Fluorescence in situ hybridization analysis demonstrated a close association of OriPYACs, some of which were visible as pairs, with host cell chromosomes, suggesting that the episomes replicate once per cell cycle and that stability is achieved by attachment to host chromosomes, as suggested for the viral genome. The wide availability of YAC libraries, the ease of manipulation of cloned sequences in yeast cells, and the episomal stability make OriPYACs ideal for studying gene function and control of gene expression.
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MESH Headings
- Antigens, Viral/biosynthesis
- Antigens, Viral/genetics
- Cell Line, Transformed
- Chromosomes, Artificial, Yeast/physiology
- Chromosomes, Human/ultrastructure
- DNA, Circular/genetics
- DNA, Fungal/genetics
- DNA, Recombinant/genetics
- DNA-Binding Proteins/biosynthesis
- DNA-Binding Proteins/genetics
- Epstein-Barr Virus Nuclear Antigens
- Extrachromosomal Inheritance
- Herpesvirus 4, Human/genetics
- Humans
- In Situ Hybridization, Fluorescence
- Kidney/cytology
- Plasmids/physiology
- Replication Origin
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Affiliation(s)
- K Simpson
- Imperial College School of Medicine at St. Mary's London, United Kingdom
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27
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Dauwalder B, Amaya-Manzanares F, Mattox W. A human homologue of the Drosophila sex determination factor transformer-2 has conserved splicing regulatory functions. Proc Natl Acad Sci U S A 1996; 93:9004-9. [PMID: 8799144 PMCID: PMC38585 DOI: 10.1073/pnas.93.17.9004] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Regulation of gene expression through alternative pre-mRNA splicing appears to occur in all metazoans, but most of our knowledge about splicing regulators derives from studies on genetically identified factors from Drosophila. Among the best studied of these is the transformer-2 (TRA-2) protein which, in combination with the transformer (TRA) protein, directs sex-specific splicing of pre-mRNA from the sex determination gene doublesex (dsx). Here we report the identification of htra-2 alpha, a human homologue of tra-2. Two alternative types of htra-2 alpha cDNA clones were identified that encode different protein isoforms with striking organizational similarity to Drosophila tra-2 proteins. When expressed in flies, one hTRA-2 alpha isoform partially replaces the function of Drosophila TRA-2, affecting both female sexual differentiation and alternative splicing of dsx pre-mRNA. Like Drosophila TRA-2, the ability of hTRA-2 alpha to regulate dsx is female-specific and depends on the presence of the dsx splicing enhancer. These results demonstrate that htra-2 alpha has conserved a striking degree of functional specificity during evolution and leads us to suggest that, although they are likely to serve different roles in development, the tra-2 products of flies and humans have similar molecular functions.
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Affiliation(s)
- B Dauwalder
- Department of Molecular Genetics, University of Texas, M. D. Anderson Cancer Center, Houston 77030, USA
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28
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Itoh T, Shiomi T, Shiomi N, Harada Y, Wakasugi M, Matsunaga T, Nikaido O, Friedberg EC, Yamaizumi M. Rodent complementation group 8 (ERCC8) corresponds to Cockayne syndrome complementation group A. Mutat Res 1996; 362:167-74. [PMID: 8596535 DOI: 10.1016/0921-8777(95)00046-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
US31 is a UV-sensitive mutant cell line (rodent complementation group 8) derived from a mouse T cell line L5178Y. We analyzed removal kinetics for UV-induced cyclobutane pyrimidine dimers and (6-4) photoproducts in US31 cells using monoclonal antibodies against these photoproducts. While nearly all (6-4) photoproducts were repaired within 6 h after UV-irradiation, more than 70% of cyclobutane pyrimidine dimers remained unrepaired even 24 h after UV-irradiation. These kinetics resembled those of Cockayne syndrome (CS) cells. Since US31 cells had a low efficiency of cell fusion and transfection, which hampered both complementation tests and gene cloning, we constructed fibroblastic complementation group 8 cell line 6L1030 by fusion of US31 cells with X-irradiated normal mouse fibroblastic LTA cells. Complementation tests by cell fusion and transfection using 6L1030 cells revealed that rodent complementation group 8 corresponded to CS complementation group A.
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Affiliation(s)
- T Itoh
- Department of Cell Genetics, Kumamoto University School of Medicine, Japan
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29
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Carstens CP, Gallo JC, Maher VM, McCormick JJ, Fahl WE. A system utilizing Epstein-Barr virus-based expression vectors for the functional cloning of human fibroblast growth regulators. Gene 1995; 164:195-202. [PMID: 7590331 DOI: 10.1016/0378-1119(95)00466-j] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The acquired ability of adherent mammalian cells to grow in suspension is closely linked to tumorigenic transformation. The anchorage-independence phenotype is likely to result from bypassing an adherence-responsive cell-cycle check-point at the G1/S boundary of the cell cycle. In order to identify genes that are part of or act upon the anchorage signal transduction pathway, we have developed a system which allows functional cloning of regulatory genes by expression of libraries of cDNA inserts either in the sense or antisense direction. The system is comprised of two components: (i) the library expression vectors, CMV-EL and C1E-EL, containing EBoriP for replication in EBN A-1-expressing cells, an expression cassette with a multiple cloning site suitable for directional insertion of cDNA libraries generated by standard protocols, and loxP sites which allow rapid manipulation of recovered vectors without the use of restriction enzymes and (ii) the EBNA-1-producing cell line, BB-5, a derivative of the immortalized, non-tumorigenic and anchorage-dependent human fibroblast cell line, MSU1.1. The growth characteristics of BB-5 cells did not differ from its parental cell line. BB-5 cells supported the episomal replication of CMV-EL and C1E-EL and allowed recovery of the vector from Hirt lysates of transfected BB-5 cells. BB-5 cells transformed to anchorage-independent growth by transfection with a mutant c-Ha-ras gene inserted into CMV-EL could be accurately and efficiently identified in a background of non-transfected BB5 cells by screening for anchorage-independent colonies with the aid of computer-assisted image analysis.
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Affiliation(s)
- C P Carstens
- McArdle Laboratory for Cancer Research, University of Wisconsin Medical School, Madison 53706, USA
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30
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Steimle V, Mach B. Complementation cloning of mammalian transcriptional regulators: the example of MHC class II gene regulators. Curr Opin Genet Dev 1995; 5:646-51. [PMID: 8664553 DOI: 10.1016/0959-437x(95)80034-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Cloning by complementation of mutant cell lines is a powerful way in which to identify and isolate important regulatory genes on the basis of functional assays. The recent cloning of two essential regulators of major histocompatibility complex (MHC) class II gene expression has not only advanced our understanding of the complex mechanisms controlling these genes, but also helps to illustrate the feasibility of this approach for the study of mammalian gene regulation.
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Affiliation(s)
- V Steimle
- Department of Genetics and Microbiology, University of Geneva Medical School, Switzerland
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31
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Abstract
Recent years have seen a dramatic expansion in the range of applications of expression cloning techniques. New vectors and detection methods promise to further broaden the applicability of function-based screening approaches to problems in gene discovery. A major theme in the past year has been the introduction of engineered reporter cells that heighten the sensitivity with which clones expressing cDNAs can be identified.
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Affiliation(s)
- B Seed
- Department of Molecular Biology, Massachusetts General Hospital, Boston 02114, USA
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32
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Li L, Lu X, Peterson CA, Legerski RJ. An interaction between the DNA repair factor XPA and replication protein A appears essential for nucleotide excision repair. Mol Cell Biol 1995; 15:5396-402. [PMID: 7565690 PMCID: PMC230789 DOI: 10.1128/mcb.15.10.5396] [Citation(s) in RCA: 201] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Replication protein A (RPA) is required for simian virus 40-directed DNA replication in vitro and for nucleotide excision repair (NER). Here we report that RPA and the human repair protein XPA specifically interact both in vitro and in vivo. Mapping of the RPA-interactive domains in XPA revealed that both of the largest subunits of RPA, RPA-70 and RPA-34, interact with XPA at distinct sites. A domain involved in mediating the interaction with RPA-70 was located between XPA residues 153 and 176. Deletion of highly conserved motifs within this region identified two mutants that were deficient in binding RPA in vitro and highly defective in NER both in vitro and in vivo. A second domain mediating the interaction with RPA-34 was identified within the first 58 residues in XPA. Deletion of this region, however, only moderately affects the complementing activity of XPA in vivo. Finally, the XPA-RPA complex is shown to have a greater affinity for damaged DNA than XPA alone. Taken together, these results indicate that the interaction between XPA and RPA is required for NER but that only the interaction with RPA-70 is essential.
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Affiliation(s)
- L Li
- Department of Molecular Genetics, University of Texas M. D. Anderson Cancer Center, Houston 77030, USA
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33
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Henning KA, Li L, Iyer N, McDaniel LD, Reagan MS, Legerski R, Schultz RA, Stefanini M, Lehmann AR, Mayne LV, Friedberg EC. The Cockayne syndrome group A gene encodes a WD repeat protein that interacts with CSB protein and a subunit of RNA polymerase II TFIIH. Cell 1995; 82:555-64. [PMID: 7664335 DOI: 10.1016/0092-8674(95)90028-4] [Citation(s) in RCA: 344] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The hereditary disease Cockayne syndrome (CS) is characterized by a complex clinical phenotype. CS cells are abnormally sensitive to ultraviolet radiation and are defective in the repair of transcriptionally active genes. The cloned CSB gene encodes a member of a protein family that includes the yeast Snf2 protein, a component of the transcriptional regulator Swi/Snf. We report the cloning of the CSA cDNA, which can encode a WD repeat protein. Mutations in the cDNA have been identified in CS-A cell lines. CSA protein interacts with CSB protein and with p44 protein, a subunit of the human RNA polymerase II transcription factor IIH. These observations suggest that the products of the CSA and CSB genes are involved in transcription.
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Affiliation(s)
- K A Henning
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas 75235, USA
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34
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Tebbs RS, Zhao Y, Tucker JD, Scheerer JB, Siciliano MJ, Hwang M, Liu N, Legerski RJ, Thompson LH. Correction of chromosomal instability and sensitivity to diverse mutagens by a cloned cDNA of the XRCC3 DNA repair gene. Proc Natl Acad Sci U S A 1995; 92:6354-8. [PMID: 7603995 PMCID: PMC41516 DOI: 10.1073/pnas.92.14.6354] [Citation(s) in RCA: 210] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The mutagen-sensitive CHO line irs1SF was previously isolated on the basis of hypersensitivity to ionizing radiation and was found to be chromosomally unstable as well as cross-sensitive to diverse kinds of DNA-damaging agents. The analysis of somatic cell hybrids formed between irs1SF and human lymphocytes implicated a human gene (defined as XRCC3; x-ray repair cross-complementing), which partially restored mitomycin C resistance to the mutant. A functional cDNA that confers mitomycin C resistance was transferred to irs1SF cells by transforming them with an expression cDNA library and obtaining primary and secondary transformants. Functional cDNA clones were recovered from a cosmid library prepared from a secondary transformant. Transformants also showed partial correction of sensitivity to cisplatin and gamma-rays, efficient correction of chromosomal instability, and substantially improved plating efficiency and growth rate. The XRCC3 cDNA insert is approximately 2.5 kb and detects an approximately 3.0-kb mRNA on Northern blots. The cDNA was mapped by fluorescence in situ hybridization to human chromosome 14q32.3, which was consistent with the chromosome concordance data of two independent hybrid clone panels.
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Affiliation(s)
- R S Tebbs
- Biology and Biotechnology Research Program, Lawrence Livermore National Laboratory, CA 94551-0808, USA
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35
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Brickell PM, Patel MS. Epstein-Barr virus replication studies and their application to vector design. Mol Biotechnol 1995; 3:199-205. [PMID: 7552689 DOI: 10.1007/bf02789330] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Vectors containing elements of the Epstein-Barr virus genome are used primarily to maintain cloned DNA inserts as plasmids in mammalian cells. However, Epstein-Bar-virus-based vectors have also been valuable tools in the hands of those studying the life cycle of Epstein-Barr virus. In this article, we discuss those characteristics of Epstein-Barr virus and its life cycle that have been used in vector construction and describe methods that are particularly applicable to the use of Epstein-Barr-virus-based vectors.
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Affiliation(s)
- P M Brickell
- Department of Molecular Pathology, University College London Medical School, UK
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36
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Li L, Peterson CA, Lu X, Legerski RJ. Mutations in XPA that prevent association with ERCC1 are defective in nucleotide excision repair. Mol Cell Biol 1995; 15:1993-8. [PMID: 7891694 PMCID: PMC230426 DOI: 10.1128/mcb.15.4.1993] [Citation(s) in RCA: 107] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The human repair proteins XPA and ERCC1 have been shown to be absolutely required for the incision step of nucleotide excision repair, and recently we identified an interaction between these two proteins both in vivo and in vitro (L. Li, S. J. Elledge, C. A. Peterson, E. S. Bales, and R. J. Legerski, Proc. Natl. Acad. Sci. USA 91:5012-5016, 1994). In this report, we demonstrate the functional relevance of this interaction. The ERCC1-binding domain on XPA was previously mapped to a region containing two highly conserved XPA sequences, Gly-72 to Phe-75 and Glu-78 to Glu-84, which are termed the G and E motifs, respectively. Site-specific mutagenesis was used to independently delete these motifs and create two XPA mutants referred to as delta G and delta E. In vitro, the binding of ERCC1 to delta E was reduced by approximately 70%, and binding to delta G was undetectable; furthermore, both mutants failed to complement XPA cell extracts in an in vitro DNA repair synthesis assay. In vivo, the delta E mutant exhibited an intermediate level of complementation of XPA cells and the delta G mutant exhibited little or no complementation. In addition, the delta G mutant inhibited repair synthesis in wild-type cell extracts, indicating that it is a dominant negative mutant. The delta E and delta G mutations, however, did not affect preferential binding of XPA to damaged DNA. These results suggest that the association between XPA and ERCC1 is a required step in the nucleotide excision repair pathway and that the probable role of the interaction is to recruit the ERCC1 incision complex to the damage site. Finally, the affinity of the XPA-ERCC1 complex was found to increase as a function of salt concentration, indicating a hydrophobic interaction; the half-life of the complex was determined to be approximately 90 min.
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Affiliation(s)
- L Li
- Department of Molecular Genetics, University of Texas M. D. Anderson Cancer Center, Houston 77030
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37
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Ziv Y, Bar-Shira A, Jorgensen TJ, Russell PS, Sartiel A, Shows TB, Eddy RL, Buchwald M, Legerski R, Schimke RT, Shiloh Y. Human cDNA clones that modify radiomimetic sensitivity of ataxia-telangiectasia (group A) cells. SOMATIC CELL AND MOLECULAR GENETICS 1995; 21:99-111. [PMID: 7570189 DOI: 10.1007/bf02255785] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Genes responsible for genetic diseases with increased sensitivity to DNA-damaging agents can be identified using complementation cloning. This strategy is based on in vitro complementation of the cellular sensitivity by gene transfer. Ataxia-telangiectasia (A-T) is a multisystem autosomal recessive disorder involving cellular sensitivity to ionizing radiation and radiomimetic drugs. A-T is genetically heterogeneous, with four complementation groups. We attempted to identify cDNA clones that modify the radiomimetic sensitivity of A-T cells assigned to complementation group [A-T(A)]. The cells were transfected with human cDNA libraries cloned in episomal vectors, and various protocols of radiomimetic selection were applied. Thirteen cDNAs rescued from survivor cells were found to confer various degrees of radiomimetic resistance to A-T(A) cells upon repeated introduction, and one of them also partially influenced another feature of the A-T phenotype, radioresistant DNA synthesis. None of the clones mapped to the A-T locus on chromosome 11q22-23. Nine of the clones were derived from known genes, some of which are involved in cellular stress responses. We concluded that a number of different genes, not necessarily associated with A-T, can influence the response of A-T cells to radiomimetic drugs, and hence the complementation cloning approach may be less applicable to A-T than to other diseases involving abnormal processing of DNA damage.
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MESH Headings
- Antibiotics, Antineoplastic/pharmacology
- Antigens, Viral/biosynthesis
- Antigens, Viral/genetics
- Ataxia Telangiectasia/genetics
- Cell Line, Transformed
- Cell Survival/drug effects
- Cell Survival/radiation effects
- Cerebellum/metabolism
- Chromosome Mapping
- Cloning, Molecular
- DNA Replication
- DNA, Complementary
- DNA-Binding Proteins/biosynthesis
- DNA-Binding Proteins/genetics
- Dose-Response Relationship, Drug
- Dose-Response Relationship, Radiation
- Epstein-Barr Virus Nuclear Antigens
- Fibroblasts/metabolism
- Gene Library
- Genes, Recessive
- Genetic Complementation Test
- Genetic Vectors
- HeLa Cells
- Humans
- Lymphocytes/metabolism
- Promoter Regions, Genetic
- Simian virus 40
- Streptonigrin/pharmacology
- Transfection
- Zinostatin/pharmacology
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Affiliation(s)
- Y Ziv
- Department of Human Genetics, Sackler School of Medicine, Tel Aviv University, Ramat Aviv, Israel
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38
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39
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[5] Epstein-barr viral plasmid vectors and their amplifiable derivatives. ACTA ACUST UNITED AC 1995. [DOI: 10.1016/s1067-2389(06)80037-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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40
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Abstract
Vectors based on Epstein-Barr virus (EBV) have been useful for cloning and gene expression studies in primate cells. However, these vectors do not replicate in rodent cells. We demonstrate here that the addition of large fragments of mammalian DNA to vectors containing the EBNA-1 gene (encoding the Epstein-Barr nuclear antigen-1) and the family of repeats from EBV generates autonomously replicating vectors which are stably maintained as extrachromosomal plasmids in hamster cells. By using a density-shift assay in Cs2SO4 density gradients, we demonstrate that the plasmids replicate once per cell cycle at high efficiency. These plasmids represent, for rodent cells, the only available class of stable, autonomous vectors replicating once per cell cycle. It is likely that this type of EBV-based autonomous replication system can also be extended to other organisms for which stable, extrachromosomal plasmid systems are not available.
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Affiliation(s)
- P J Krysan
- Department of Genetics, Stanford University School of Medicine, CA 94305
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41
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Li L, Bales ES, Peterson CA, Legerski RJ. Characterization of molecular defects in xeroderma pigmentosum group C. Nat Genet 1993; 5:413-7. [PMID: 8298653 DOI: 10.1038/ng1293-413] [Citation(s) in RCA: 100] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Xeroderma pigmentosum (XP) is a rare autosomal recessive disease of humans characterized by an accelerated chronic degeneration of sun-exposed areas of the body, including an elevated risk of developing cancers of the skin. We recently reported the isolation of a gene XPCC that complements the repair deficiency of cultured XP-C cells. Here we report the results of a characterization of XPCC at the nucleotide level in five XP-C cell lines. Each cell line exhibited a unique mutation that correlated well with the cellular DNA repair deficiency and the clinical severity of the disease. These results extend our previous observations and indicate that defects in XPCC cause Xeroderma pigmentosum group C.
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Affiliation(s)
- L Li
- Department of Molecular Genetics, University of Texas M.D. Anderson Cancer Center, Houston 77030
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42
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Human ERCC5 cDNA-cosmid complementation for excision repair and bipartite amino acid domains conserved with RAD proteins of Saccharomyces cerevisiae and Schizosaccharomyces pombe. Mol Cell Biol 1993. [PMID: 8413238 DOI: 10.1128/mcb.13.10.6393] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Several human genes related to DNA excision repair (ER) have been isolated via ER cross-species complementation (ERCC) of UV-sensitive CHO cells. We have now isolated and characterized cDNAs for the human ERCC5 gene that complement CHO UV135 cells. The ERCC5 mRNA size is about 4.6 kb. Our available cDNA clones are partial length, and no single clone was active for UV135 complementation. When cDNAs were mixed pairwise with a cosmid clone containing an overlapping 5'-end segment of the ERCC5 gene, DNA transfer produced UV-resistant colonies with 60 to 95% correction of UV resistance relative to either a genomic ERCC5 DNA transformant or the CHO AA8 progenitor cells. cDNA-cosmid transformants regained intermediate levels (20 to 45%) of ER-dependent reactivation of a UV-damaged pSVCATgpt reporter plasmid. Our evidence strongly implicates an in situ recombination mechanism in cDNA-cosmid complementation for ER. The complete deduced amino acid sequence of ERCC5 was reconstructed from several cDNA clones encoding a predicted protein of 1,186 amino acids. The ERCC5 protein has extensive sequence similarities, in bipartite domains A and B, to products of RAD repair genes of two yeasts, Saccharomyces cerevisiae RAD2 and Schizosaccharomyces pombe rad13. Sequence, structural, and functional data taken together indicate that ERCC5 and its relatives are probable functional homologs. A second locus represented by S. cerevisiae YKL510 and S. pombe rad2 genes is structurally distinct from the ERCC5 locus but retains vestigial A and B domain similarities. Our analyses suggest that ERCC5 is a nuclear-localized protein with one or more highly conserved helix-loop-helix segments within domains A and B.
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43
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MacInnes MA, Dickson JA, Hernandez RR, Learmonth D, Lin GY, Mudgett JS, Park MS, Schauer S, Reynolds RJ, Strniste GF. Human ERCC5 cDNA-cosmid complementation for excision repair and bipartite amino acid domains conserved with RAD proteins of Saccharomyces cerevisiae and Schizosaccharomyces pombe. Mol Cell Biol 1993; 13:6393-402. [PMID: 8413238 PMCID: PMC364698 DOI: 10.1128/mcb.13.10.6393-6402.1993] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Several human genes related to DNA excision repair (ER) have been isolated via ER cross-species complementation (ERCC) of UV-sensitive CHO cells. We have now isolated and characterized cDNAs for the human ERCC5 gene that complement CHO UV135 cells. The ERCC5 mRNA size is about 4.6 kb. Our available cDNA clones are partial length, and no single clone was active for UV135 complementation. When cDNAs were mixed pairwise with a cosmid clone containing an overlapping 5'-end segment of the ERCC5 gene, DNA transfer produced UV-resistant colonies with 60 to 95% correction of UV resistance relative to either a genomic ERCC5 DNA transformant or the CHO AA8 progenitor cells. cDNA-cosmid transformants regained intermediate levels (20 to 45%) of ER-dependent reactivation of a UV-damaged pSVCATgpt reporter plasmid. Our evidence strongly implicates an in situ recombination mechanism in cDNA-cosmid complementation for ER. The complete deduced amino acid sequence of ERCC5 was reconstructed from several cDNA clones encoding a predicted protein of 1,186 amino acids. The ERCC5 protein has extensive sequence similarities, in bipartite domains A and B, to products of RAD repair genes of two yeasts, Saccharomyces cerevisiae RAD2 and Schizosaccharomyces pombe rad13. Sequence, structural, and functional data taken together indicate that ERCC5 and its relatives are probable functional homologs. A second locus represented by S. cerevisiae YKL510 and S. pombe rad2 genes is structurally distinct from the ERCC5 locus but retains vestigial A and B domain similarities. Our analyses suggest that ERCC5 is a nuclear-localized protein with one or more highly conserved helix-loop-helix segments within domains A and B.
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Affiliation(s)
- M A MacInnes
- Life Sciences Division, Los Alamos National Laboratory, New Mexico 87545
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44
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Liu P, Tarlé SA, Hajra A, Claxton DF, Marlton P, Freedman M, Siciliano MJ, Collins FS. Fusion between transcription factor CBF beta/PEBP2 beta and a myosin heavy chain in acute myeloid leukemia. Science 1993; 261:1041-4. [PMID: 8351518 DOI: 10.1126/science.8351518] [Citation(s) in RCA: 542] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The pericentric inversion of chromosome 16 [inv(16)(p13q22)] is a characteristic karyotypic abnormality associated with acute myeloid leukemia, most commonly of the M4Eo subtype. The 16p and 16q breakpoints were pinpointed by yeast artificial chromosome and cosmid cloning, and the two genes involved in this inversion were identified. On 16q the inversion occurred near the end of the coding region for CBF beta, also known as PEBP2 beta, a subunit of a heterodimeric transcription factor regulating genes expressed in T cells; on 16p a smooth muscle myosin heavy chain (SMMHC) gene (MYH11) was interrupted. In six of six inv(16) patient samples tested, an in-frame fusion messenger RNA was demonstrated that connected the first 165 amino acids of CBF beta with the tail region of SMMHC. The repeated coiled coil of SMMHC may result in dimerization of the CBF beta fusion protein, which in turn would lead to alterations in transcriptional regulation and contribute to leukemic transformation.
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Affiliation(s)
- P Liu
- Howard Hughes Medical Institute, Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor 48109
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45
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Legerski R, Peterson C. Expression cloning of a human DNA repair gene involved in xeroderma pigmentosum group C. Nature 1992; 359:70-3. [PMID: 1522891 DOI: 10.1038/359070a0] [Citation(s) in RCA: 179] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Xeroderma pigmentosum (XP) is a rare human autosomal recessive disease characterized by solar sensitivity, high predisposition for developing cancers on areas exposed to sunlight, and, in some cases, neurological abnormalities. XP cells are defective in DNA repair, and complementation of this defect has been used to identify eight genetic groups (A-G and variant). We have developed a simple, highly efficient complementary DNA expression system for use in human cells. Here we use this system to isolate a cDNA clone that restores the ultraviolet sensitivity and unscheduled DNA synthesis of XP-C cells to normal levels. The XP-C complementing clone XPCC encodes a highly hydrophilic protein which is composed of a predicted 823 amino acids and shares limited homology with the product of the yeast DNA repair gene RAD4. The XPCC transcript is undetectable by northern blotting in most XP-C cell lines examined.
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Affiliation(s)
- R Legerski
- Department of Molecular Genetics, University of Texas, M. D. Anderson Cancer Center, Houston 77030
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