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Pabba MK, Ritter C, Chagin VO, Meyer J, Celikay K, Stear JH, Loerke D, Kolobynina K, Prorok P, Schmid AK, Leonhardt H, Rohr K, Cardoso MC. Replisome loading reduces chromatin motion independent of DNA synthesis. eLife 2023; 12:RP87572. [PMID: 37906089 PMCID: PMC10617993 DOI: 10.7554/elife.87572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2023] Open
Abstract
Chromatin has been shown to undergo diffusional motion, which is affected during gene transcription by RNA polymerase activity. However, the relationship between chromatin mobility and other genomic processes remains unclear. Hence, we set out to label the DNA directly in a sequence unbiased manner and followed labeled chromatin dynamics in interphase human cells expressing GFP-tagged proliferating cell nuclear antigen (PCNA), a cell cycle marker and core component of the DNA replication machinery. We detected decreased chromatin mobility during the S-phase compared to G1 and G2 phases in tumor as well as normal diploid cells using automated particle tracking. To gain insight into the dynamical organization of the genome during DNA replication, we determined labeled chromatin domain sizes and analyzed their motion in replicating cells. By correlating chromatin mobility proximal to the active sites of DNA synthesis, we showed that chromatin motion was locally constrained at the sites of DNA replication. Furthermore, inhibiting DNA synthesis led to increased loading of DNA polymerases. This was accompanied by accumulation of the single-stranded DNA binding protein on the chromatin and activation of DNA helicases further restricting local chromatin motion. We, therefore, propose that it is the loading of replisomes but not their catalytic activity that reduces the dynamics of replicating chromatin segments in the S-phase as well as their accessibility and probability of interactions with other genomic regions.
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Affiliation(s)
| | - Christian Ritter
- Biomedical Computer Vision Group, BioQuant, IPMB, Heidelberg UniversityHeidelbergGermany
| | - Vadim O Chagin
- Department of Biology, Technical University of DarmstadtDarmstadtGermany
- Institute of Cytology RASSt. PetersburgRussian Federation
| | - Janis Meyer
- Biomedical Computer Vision Group, BioQuant, IPMB, Heidelberg UniversityHeidelbergGermany
| | - Kerem Celikay
- Biomedical Computer Vision Group, BioQuant, IPMB, Heidelberg UniversityHeidelbergGermany
| | - Jeffrey H Stear
- EMBL Australia Node in Single Molecule Science, University of New South WalesSydneyAustralia
| | - Dinah Loerke
- Department of Physics & Astronomy, University of DenverDenverUnited States
| | - Ksenia Kolobynina
- Department of Biology, Technical University of DarmstadtDarmstadtGermany
| | - Paulina Prorok
- Department of Biology, Technical University of DarmstadtDarmstadtGermany
| | - Alice Kristin Schmid
- Biomedical Computer Vision Group, BioQuant, IPMB, Heidelberg UniversityHeidelbergGermany
| | | | - Karl Rohr
- Biomedical Computer Vision Group, BioQuant, IPMB, Heidelberg UniversityHeidelbergGermany
| | - M Cristina Cardoso
- Department of Biology, Technical University of DarmstadtDarmstadtGermany
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2
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Zangarelli C, Arnaiz O, Bourge M, Gorrichon K, Jaszczyszyn Y, Mathy N, Escoriza L, Bétermier M, Régnier V. Developmental timing of programmed DNA elimination in Paramecium tetraurelia recapitulates germline transposon evolutionary dynamics. Genome Res 2022; 32:2028-2042. [PMID: 36418061 PMCID: PMC9808624 DOI: 10.1101/gr.277027.122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 11/11/2022] [Indexed: 11/24/2022]
Abstract
With its nuclear dualism, the ciliate Paramecium constitutes a unique model to study how host genomes cope with transposable elements (TEs). P. tetraurelia harbors two germline micronuclei (MICs) and a polyploid somatic macronucleus (MAC) that develops from one MIC at each sexual cycle. Throughout evolution, the MIC genome has been continuously colonized by TEs and related sequences that are removed from the somatic genome during MAC development. Whereas TE elimination is generally imprecise, excision of approximately 45,000 TE-derived internal eliminated sequences (IESs) is precise, allowing for functional gene assembly. Programmed DNA elimination is concomitant with genome amplification. It is guided by noncoding RNAs and repressive chromatin marks. A subset of IESs is excised independently of this epigenetic control, raising the question of how IESs are targeted for elimination. To gain insight into the determinants of IES excision, we established the developmental timing of DNA elimination genome-wide by combining fluorescence-assisted nuclear sorting with high-throughput sequencing. Essentially all IESs are excised within only one endoreplication round (32C to 64C), whereas TEs are eliminated at a later stage. We show that DNA elimination proceeds independently of replication. We defined four IES classes according to excision timing. The earliest excised IESs tend to be independent of epigenetic factors, display strong sequence signals at their ends, and originate from the most ancient integration events. We conclude that old IESs have been optimized during evolution for early and accurate excision by acquiring stronger sequence determinants and escaping epigenetic control.
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Affiliation(s)
- Coralie Zangarelli
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette Cedex, France
| | - Olivier Arnaiz
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette Cedex, France
| | - Mickaël Bourge
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette Cedex, France
| | - Kevin Gorrichon
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette Cedex, France
| | - Yan Jaszczyszyn
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette Cedex, France
| | - Nathalie Mathy
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette Cedex, France
| | - Loïc Escoriza
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette Cedex, France
| | - Mireille Bétermier
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette Cedex, France
| | - Vinciane Régnier
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette Cedex, France;,Université Paris Cité, UFR Sciences du Vivant, 75205 Paris Cedex 13, France
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3
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Rausch C, Zhang P, Casas-Delucchi CS, Daiß JL, Engel C, Coster G, Hastert FD, Weber P, Cardoso MC. Cytosine base modifications regulate DNA duplex stability and metabolism. Nucleic Acids Res 2021; 49:12870-12894. [PMID: 34133727 PMCID: PMC8682791 DOI: 10.1093/nar/gkab509] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 05/26/2021] [Accepted: 06/03/2021] [Indexed: 12/14/2022] Open
Abstract
DNA base modifications diversify the genome and are essential players in development. Yet, their influence on DNA physical properties and the ensuing effects on genome metabolism are poorly understood. Here, we focus on the interplay of cytosine modifications and DNA processes. We show by a combination of in vitro reactions with well-defined protein compositions and conditions, and in vivo experiments within the complex networks of the cell that cytosine methylation stabilizes the DNA helix, increasing its melting temperature and reducing DNA helicase and RNA/DNA polymerase speed. Oxidation of methylated cytosine, however, reverts the duplex stabilizing and genome metabolic effects to the level of unmodified cytosine. We detect this effect with DNA replication and transcription proteins originating from different species, ranging from prokaryotic and viral to the eukaryotic yeast and mammalian proteins. Accordingly, lack of cytosine methylation increases replication fork speed by enhancing DNA helicase unwinding speed in cells. We further validate that this cannot simply be explained by altered global DNA decondensation, changes in histone marks or chromatin structure and accessibility. We propose that the variegated deposition of cytosine modifications along the genome regulates DNA helix stability, thereby providing an elementary mechanism for local fine-tuning of DNA metabolism.
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Affiliation(s)
- Cathia Rausch
- Cell Biology and Epigenetics, Department of Biology, Technical University of Darmstadt, 64287 Darmstadt, Germany
| | - Peng Zhang
- Cell Biology and Epigenetics, Department of Biology, Technical University of Darmstadt, 64287 Darmstadt, Germany.,Center for Tissue Engineering and Stem Cell Research, Guizhou Medical University, Guiyang, Guizhou 550004, China
| | | | - Julia L Daiß
- Regensburg Center for Biochemistry, University of Regensburg, 93053 Regensburg, Germany
| | - Christoph Engel
- Regensburg Center for Biochemistry, University of Regensburg, 93053 Regensburg, Germany
| | - Gideon Coster
- Chester Beatty Laboratories, The Institute of Cancer Research, London SW3 6JB, UK
| | - Florian D Hastert
- Cell Biology and Epigenetics, Department of Biology, Technical University of Darmstadt, 64287 Darmstadt, Germany
| | - Patrick Weber
- Cell Biology and Epigenetics, Department of Biology, Technical University of Darmstadt, 64287 Darmstadt, Germany
| | - M Cristina Cardoso
- Cell Biology and Epigenetics, Department of Biology, Technical University of Darmstadt, 64287 Darmstadt, Germany
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Feldman T, Bercovich A, Moskovitz Y, Chapal-Ilani N, Mitchell A, Medeiros JJF, Biezuner T, Kaushansky N, Minden MD, Gupta V, Milyavsky M, Livneh Z, Tanay A, Shlush LI. Recurrent deletions in clonal hematopoiesis are driven by microhomology-mediated end joining. Nat Commun 2021; 12:2455. [PMID: 33911081 PMCID: PMC8080710 DOI: 10.1038/s41467-021-22803-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 03/29/2021] [Indexed: 01/19/2023] Open
Abstract
The mutational mechanisms underlying recurrent deletions in clonal hematopoiesis are not entirely clear. In the current study we inspect the genomic regions around recurrent deletions in myeloid malignancies, and identify microhomology-based signatures in CALR, ASXL1 and SRSF2 loci. We demonstrate that these deletions are the result of double stand break repair by a PARP1 dependent microhomology-mediated end joining (MMEJ) pathway. Importantly, we provide evidence that these recurrent deletions originate in pre-leukemic stem cells. While DNA polymerase theta (POLQ) is considered a key component in MMEJ repair, we provide evidence that pre-leukemic MMEJ (preL-MMEJ) deletions can be generated in POLQ knockout cells. In contrast, aphidicolin (an inhibitor of replicative polymerases and replication) treatment resulted in a significant reduction in preL-MMEJ. Altogether, our data indicate an association between POLQ independent MMEJ and clonal hematopoiesis and elucidate mutational mechanisms involved in the very first steps of leukemia evolution.
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Affiliation(s)
- Tzah Feldman
- Department of Immunology, Weizmann Institute of Science, Rehovot, Israel
| | - Akhiad Bercovich
- Department of Computer Science and Applied Mathematics, Weizmann Institute of Science, Rehovot, Israel
| | - Yoni Moskovitz
- Department of Immunology, Weizmann Institute of Science, Rehovot, Israel
| | - Noa Chapal-Ilani
- Department of Immunology, Weizmann Institute of Science, Rehovot, Israel
| | - Amanda Mitchell
- Princess Margaret Cancer Centre, University Health Network (UHN), Toronto, ON, Canada
| | - Jessie J F Medeiros
- Princess Margaret Cancer Centre, University Health Network (UHN), Toronto, ON, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Tamir Biezuner
- Department of Immunology, Weizmann Institute of Science, Rehovot, Israel
| | - Nathali Kaushansky
- Department of Immunology, Weizmann Institute of Science, Rehovot, Israel
| | - Mark D Minden
- Princess Margaret Cancer Centre, University Health Network (UHN), Toronto, ON, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
- Department of Medicine, University of Toronto, Toronto, ON, Canada
- Division of Medical Oncology and Hematology, University Health Network, Toronto, ON, Canada
| | - Vikas Gupta
- Princess Margaret Cancer Centre, University Health Network (UHN), Toronto, ON, Canada
- Department of Medicine, University of Toronto, Toronto, ON, Canada
- Division of Medical Oncology and Hematology, University Health Network, Toronto, ON, Canada
| | - Michael Milyavsky
- Department of Pathology, Tel-Aviv University, Tel-Aviv, Israel
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - Zvi Livneh
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Amos Tanay
- Department of Computer Science and Applied Mathematics, Weizmann Institute of Science, Rehovot, Israel
| | - Liran I Shlush
- Department of Immunology, Weizmann Institute of Science, Rehovot, Israel.
- Princess Margaret Cancer Centre, University Health Network (UHN), Toronto, ON, Canada.
- Division of Hematology, Rambam Healthcare Campus, Haifa, Israel.
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5
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Replication stress induces mitotic death through parallel pathways regulated by WAPL and telomere deprotection. Nat Commun 2019; 10:4224. [PMID: 31530811 PMCID: PMC6748914 DOI: 10.1038/s41467-019-12255-w] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Accepted: 08/29/2019] [Indexed: 02/07/2023] Open
Abstract
Mitotic catastrophe is a broad descriptor encompassing unclear mechanisms of cell death. Here we investigate replication stress-driven mitotic catastrophe in human cells and identify that replication stress principally induces mitotic death signalled through two independent pathways. In p53-compromised cells we find that lethal replication stress confers WAPL-dependent centromere cohesion defects that maintain spindle assembly checkpoint-dependent mitotic arrest in the same cell cycle. Mitotic arrest then drives cohesion fatigue and triggers mitotic death through a primary pathway of BAX/BAK-dependent apoptosis. Simultaneously, a secondary mitotic death pathway is engaged through non-canonical telomere deprotection, regulated by TRF2, Aurora B and ATM. Additionally, we find that suppressing mitotic death in replication stressed cells results in distinct cellular outcomes depending upon how cell death is averted. These data demonstrate how replication stress-induced mitotic catastrophe signals cell death with implications for cancer treatment and cancer genome evolution. Mitotic catastrophe is a regulated mechanism that responds to aberrant mitoses leading to removal of damaged cells. Here the authors reveal how replication stress induces mitotic death through pathways regulated by WAPL and telomere deprotection.
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Abstract
Genomic instability is a hallmark of cancer and a common feature of human disorders, characterized by growth defects, neurodegeneration, cancer predisposition, and aging. Recent evidence has shown that DNA replication stress is a major driver of genomic instability and tumorigenesis. Cells can undergo mitosis with under-replicated DNA or unresolved DNA structures, and specific pathways are dedicated to resolving these structures during mitosis, suggesting that mitotic rescue from replication stress (MRRS) is a key process influencing genome stability and cellular homeostasis. Deregulation of MRRS following oncogene activation or loss-of-function of caretaker genes may be the cause of chromosomal aberrations that promote cancer initiation and progression. In this review, we discuss the causes and consequences of replication stress, focusing on its persistence in mitosis as well as the mechanisms and factors involved in its resolution, and the potential impact of incomplete replication or aberrant MRRS on tumorigenesis, aging and disease.
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Affiliation(s)
- Michalis Fragkos
- a CNRS UMR8200 , University Paris-Saclay , Gustave Roussy, Villejuif , France
| | - Valeria Naim
- a CNRS UMR8200 , University Paris-Saclay , Gustave Roussy, Villejuif , France
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7
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Baranovskiy AG, Babayeva ND, Suwa Y, Gu J, Pavlov YI, Tahirov TH. Structural basis for inhibition of DNA replication by aphidicolin. Nucleic Acids Res 2014; 42:14013-21. [PMID: 25429975 PMCID: PMC4267640 DOI: 10.1093/nar/gku1209] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Natural tetracyclic diterpenoid aphidicolin is a potent and specific inhibitor of B-family DNA polymerases, haltering replication and possessing a strong antimitotic activity in human cancer cell lines. Clinical trials revealed limitations of aphidicolin as an antitumor drug because of its low solubility and fast clearance from human plasma. The absence of structural information hampered the improvement of aphidicolin-like inhibitors: more than 50 modifications have been generated so far, but all have lost the inhibitory and antitumor properties. Here we report the crystal structure of the catalytic core of human DNA polymerase α (Pol α) in the ternary complex with an RNA-primed DNA template and aphidicolin. The inhibitor blocks binding of dCTP by docking at the Pol α active site and by rotating the template guanine. The structure provides a plausible mechanism for the selectivity of aphidicolin incorporation opposite template guanine and explains why previous modifications of aphidicolin failed to improve its affinity for Pol α. With new structural information, aphidicolin becomes an attractive lead compound for the design of novel derivatives with enhanced inhibitory properties for B-family DNA polymerases.
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Affiliation(s)
- Andrey G Baranovskiy
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Nigar D Babayeva
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Yoshiaki Suwa
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Jianyou Gu
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Youri I Pavlov
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE 68198, USA Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Tahir H Tahirov
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE 68198, USA
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8
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Abstract
DNA polymerase δ (Pol δ) is a member of the B-family DNA polymerases and is one of the major replicative DNA polymerases in eukaryotes. In addition to chromosomal DNA replication it is also involved in DNA repair and recombination. Pol δ is a multi-subunit complex comprised of a catalytic subunit and accessory subunits. The latter subunits play a critical role in the regulation of Pol δ functions. Recent progress in the structural characterization of Pol δ, together with a vast number of biochemical and functional studies, provides the basis for understanding the intriguing mechanisms of its regulation during DNA replication, repair and recombination. In this chapter we review the current state of the Pol δ structure-function relationship with an emphasis on the role of its accessory subunits.
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Affiliation(s)
- Tahir H Tahirov
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE, 68198-7696, USA,
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9
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Schneikert J, Grohmann A, Behrens J. Truncated APC regulates the transcriptional activity of beta-catenin in a cell cycle dependent manner. Hum Mol Genet 2006; 16:199-209. [PMID: 17189293 DOI: 10.1093/hmg/ddl464] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Most colon cancer cells express truncated versions of the tumour suppressor Adenomatous Polyposis Coli (APC). These molecules are selected during tumourigenesis for impaired beta-catenin degrading activity. In this study, we describe that truncated APC can still control the activity of beta-catenin in colon cancer cell lines via its first 20 amino acid repeat. First, we show that both endogenous and ectopically expressed truncated APC molecules can bind to beta-catenin. Second, reduction of the levels of truncated APC by RNA interference increases the activity of a beta-catenin-dependent reporter gene and stimulates the expression of the beta-catenin target gene AXIN2/conductin. This occurs without alterations of the amounts of cytosolic beta-catenin. Conversely, ectopic expression of truncated APC decreases beta-catenin-dependent transcription without affecting the intensity of immunofluorescence staining of beta-catenin in transfected cells. Third, we reveal that the APC level increases when cells reach the G1-S boundary during cell cycle progression. Simultaneously, the amount of beta-catenin bound to APC increases and the transcriptional activity of beta-catenin drops in an APC-dependent manner. Again, this occurs independently of the amounts of either total or phosphorylated cytosolic beta-catenin. Together, these results indicate that truncated APC controls the ability of beta-catenin to activate transcription. As we also show that the inhibition involves the first 20 amino acid repeat of APC, our data suggest that colon cancer cells retain a truncated APC molecule containing at least the first 20 amino acid repeat to modulate the transcriptional activity of beta-catenin in a cell cycle-dependent manner.
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Affiliation(s)
- Jean Schneikert
- Nikolaus-Fiebiger-Center for Molecular Medicine, University Erlangen-Nürnberg, Glückstrasse 6, 91054 Erlangen, Germany
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De Rijck J, Van Maele B, Debyser Z. Positional effects of the central DNA flap in HIV-1-derived lentiviral vectors. Biochem Biophys Res Commun 2005; 328:987-94. [PMID: 15707975 DOI: 10.1016/j.bbrc.2005.01.052] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2005] [Indexed: 11/27/2022]
Abstract
During reverse transcription of the human immunodeficiency virus type 1 (HIV-1), a 90- or 99-nucleotide long DNA flap is formed at the centre of the viral cDNA. The presence of a central DNA flap in lentiviral vectors improves transduction efficiency significantly. We analysed the stimulation of lentiviral vector transduction by a DNA flap present at ectopic positions in the viral cDNA. A HIV-1 vector containing the cPPT/CTS fragment immediately downstream of the 5'-LTR performed as well as the wild-type cPPT-vector. Cloning of the cPPT/CTS fragment in front of the 3'-LTR resulted as well in a vector with higher transduction efficiency than a vector without central flap. These results demonstrate that the position of the DNA flap is not essential for its function in the context of HIV-1-derived lentiviral vectors. This may have consequences for vector design and our understanding of the functioning of the HIV-1 DNA flap.
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Affiliation(s)
- Jan De Rijck
- Laboratory for Molecular Virology and Gene Therapy, KULeuven and KULAK, Flanders, Belgium
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11
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Seo BB, Wang J, Flotte TR, Yagi T, Matsuno-Yagi A. Use of the NADH-quinone oxidoreductase (NDI1) gene of Saccharomyces cerevisiae as a possible cure for complex I defects in human cells. J Biol Chem 2000; 275:37774-8. [PMID: 10982813 DOI: 10.1074/jbc.m007033200] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The Ndi1 enzyme of Saccharomyces cerevisiae is a single subunit rotenone-insensitive NADH-quinone oxidoreductase that is located on the matrix side of the inner mitochondrial membrane. We have shown previously that the NDI1 gene can be functionally expressed in Chinese hamster cells (Seo, B. B., Kitajima-Ihara, T., Chan, E. K., Scheffler, I. E., Matsuno-Yagi, A., and Yagi, T. (1998) Proc. Natl. Acad. Sci. U. S. A. 95, 9167-9171) and human embryonal kidney 293 (HEK 293) cells (Seo, B. B., Matsuno-Yagi, A., and Yagi, T. (1999) Biochim. Biochem. Acta 1412, 56-65) and that the Ndi1 protein is capable of compensating respiratory deficiencies caused by defects in the host NADH-quinone oxidoreductase (complex I). To extend the potential use of this enzyme to repair complex I deficiencies in vivo, we constructed a recombinant adeno-associated virus vector carrying the NDI1 gene (rAAV-NDI1). With rAAV-NDI1 as the gene delivery method, we were able to achieve high transduction efficiencies (nearly 100%) even in 143B cells that are difficult to transfect by lipofection or calcium phosphate precipitation methods. The NDI1 gene was successfully introduced into non-proliferating human cells using rAAV-NDI1. The expressed Ndi1 protein was shown to be functionally active just as seen for proliferating cells. Furthermore, when cells were cultured under the conditions where energy has to be provided by respiration, the NDI1-transduced cells were able to grow even in the presence of added complex I inhibitor such as rotenone and 1-methyl-4-phenylpyridinium ion. In contrast, control cells that did not receive the NDI1 gene failed to survive as anticipated. The Ndi1 protein has a great potential as a molecular remedy for complex I defects, and it is highly likely that the same strategy can be extended to correction of other mitochondrial disorders.
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Affiliation(s)
- B B Seo
- Division of Biochemistry, the Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California 92037, USA
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12
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Metharom P, Takyar S, Xia HH, Ellem KA, Macmillan J, Shepherd RW, Wilcox GE, Wei MQ. Novel bovine lentiviral vectors based on Jembrana disease virus. J Gene Med 2000; 2:176-85. [PMID: 10894263 DOI: 10.1002/(sici)1521-2254(200005/06)2:3<176::aid-jgm106>3.0.co;2-q] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Safety is a concern that must be addressed prior to any clinical use of human immunodeficiency virus (HIV)-based lentiviral vectors in human patients. Unfortunately, efforts to examine the biosafety of the vectors in preclinical animal models are hampered due to the lack of animal models for HIV infection. We have developed new lentiviral vectors based on the recently characterised Jembrana Disease Virus (JDV), which infects a specific species of cattle naturally in Bali, Indonesia. METHODS Sequences from the JDV genome were amplified by splicing overlap extension polymerase chain reaction (PCR) for the construction of transfer vectors as well as a packaging construct. Co-transfection of these two plasmids into 293T cells with a third encoding a G glycoprotein of vesicular stomatitis virus produced pseudotyped, disabled, replication defective JDV vector particles. Viral titre was obtained by transducing the cells with the supernatant harvested from transfectants and determining the number of cells expressing the transgene. PCR and Southern blotting were used to detect the presence of potential replication-competent viruses as well as transgene integration. RESULTS Bicistronic JDV vectors encoding the green fluorescent protein (GFP) and the neomycin phosphotransferase were harvested with a titre range of 0.4-1.2 x 10(6) colony forming units/ml from vector-producing cells and were further concentrated by ultracentrifugation to the high titre of approximately 10(7) CFU/ml. Vectors encoding GFP were shown to transduce and integrate efficiently into the chromosomes of a range of primary and transformed cells of different origins in different differentiation status, including growth-arrested cells, with an efficiency of 25-75%. Exhaustive testing with a marker gene transfer assay in combination with a reverse transcriptase assay and PCR amplification of samples of serially passaged, transduced cells showed that no detectable amount of replication competent lentivirus (RCL) was produced. CONCLUSIONS We showed the feasibility of the development of gene transfer vectors based on a non-primate bovine lentivirus, which will provide the opportunity for examination of the efficacy and biosafety of lentiviral vector-mediated gene transfer in vivo in animal models. JDV-based vectors may be applicable and more readily acceptable than those from HIV for human gene therapy.
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Affiliation(s)
- P Metharom
- Gene Therapy Unit, Sir Albert Sakzewski Virus Research Centre, Royal Children's Hospital, Brisbane, Queensland, Australia
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13
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Fan X, Price CM. Coordinate regulation of G- and C strand length during new telomere synthesis. Mol Biol Cell 1997; 8:2145-55. [PMID: 9362059 PMCID: PMC25698 DOI: 10.1091/mbc.8.11.2145] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/1997] [Accepted: 08/25/1997] [Indexed: 02/05/2023] Open
Abstract
We have used the ciliate Euplotes to study the role of DNA polymerase in telomeric C strand synthesis. Euplotes provides a unique opportunity to study C strand synthesis without the complication of simultaneous DNA replication because millions of new telomeres are made at a stage in the life cycle when no general DNA replication takes place. Previously we showed that the C-strands of newly synthesized telomeres have a precisely controlled length while the G-strands are more heterogeneous. This finding suggested that, although synthesis of the G-strand (by telomerase) is the first step in telomere addition, a major regulatory step occurs during subsequent C strand synthesis. We have now examined whether G- and C strand synthesis might be regulated coordinately rather than by two independent mechanisms. We accomplished this by determining what happens to G- and C strand length if C strand synthesis is partially inhibited by aphidicolin. Aphidicolin treatment caused a general lengthening of the G-strands and a large increase in C strand heterogeneity. This concomitant change in both the G- and C strand length indicates that synthesis of the two strands is coordinated. Since aphidicolin is a very specific inhibitor of DNA pol alpha and pol delta, our results suggest that this coordinate length regulation is mediated by DNA polymerase.
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Affiliation(s)
- X Fan
- Department of Chemistry, University of Nebraska, Lincoln 68588, USA
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14
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Roe T, Chow SA, Brown PO. 3'-end processing and kinetics of 5'-end joining during retroviral integration in vivo. J Virol 1997; 71:1334-40. [PMID: 8995657 PMCID: PMC191188 DOI: 10.1128/jvi.71.2.1334-1340.1997] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Retroviral replication depends on integration of viral DNA into a host cell chromosome. Integration proceeds in three steps: 3'-end processing, the endonucleolytic removal of the two terminal nucleotides from each 3' end of the viral DNA; strand transfer, the joining of the 3' ends of viral DNA to host DNA; and 5'-end joining (or gap repair), the joining of the 5' ends of viral DNA to host DNA. The 5'-end joining step has never been investigated, either for retroviral integration or for any other transposition process. We have developed an assay for 5'-end joining in vivo and have examined the kinetics of 5'-end joining for Moloney murine leukemia virus (MLV). The interval between 3'-end and 5'-end joining is estimated to be less than 1 h. This assay will be a useful tool for examining whether viral or host components mediate 5'-end joining. MLV integrates its DNA only after its host cell has completed mitosis. We show that the extent of 3'-end processing is the same in unsynchronized and aphidicolin-arrested cells. 3'-end processing therefore does not depend on mitosis.
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Affiliation(s)
- T Roe
- Department of Biochemistry, Stanford University Medical Center, California 94305, USA
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15
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Naldini L, Blömer U, Gallay P, Ory D, Mulligan R, Gage FH, Verma IM, Trono D. In vivo gene delivery and stable transduction of nondividing cells by a lentiviral vector. Science 1996; 272:263-7. [PMID: 8602510 DOI: 10.1126/science.272.5259.263] [Citation(s) in RCA: 3614] [Impact Index Per Article: 129.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A retroviral vector system based on the human immunodeficiency virus (HIV) was developed that, in contrast to a murine leukemia virus-based counterpart, transduced heterologous sequences into HeLa cells and rat fibroblasts blocked in the cell cycle, as well as into human primary macrophages. Additionally, the HIV vector could mediate stable in vivo gene transfer into terminally differentiated neurons. The ability of HIV-based viral vectors to deliver genes in vivo into nondividing cells could increase the applicability of retroviral vectors in human gene therapy.
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Affiliation(s)
- L Naldini
- Salk Institute, La Jolla, CA 92037, USA
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16
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Abstract
Synthetic oligonucleotides of defined sequence were used to examine the mechanism of calf thymus DNA polymerase alpha inhibition by aphidicolin. Aphidicolin competes with each of the four dNTPs for binding to a pol alpha-DNA binary complex and thus should not be viewed as a dCTP analogue. Kinetic evidence shows that inhibition proceeds through the formation of a pol alpha.DNA.aphidicolin ternary complex, while DNase I protection experiments provide direct physical evidence. When deoxyguanosine is the next base to be replicated, Ki = 0.2 microM. In contrast, the Ki is 10-fold higher when the other dNMPs are at this position. Formation of a pol alpha.DNA.aphidicolin ternary complex did not inhibit the primase activity of the pol alpha.primase complex. Neither the rate of primer synthesis nor the size distribution of primers 2-10 nucleotides long was changed. Elongation of the primase-synthesized primers by pol alpha was inhibited both by ternary complex formation using exogenously added DNA and by aphidicolin alone.
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Affiliation(s)
- R Sheaff
- Department of Chemistry and Biochemistry, University of Colorado, Boulder 80309-0215
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17
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Richard MC, Litvak S, Castroviejo M. DNA polymerase B from wheat embryos: a plant delta-like DNA polymerase. Arch Biochem Biophys 1991; 287:141-50. [PMID: 1654800 DOI: 10.1016/0003-9861(91)90399-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Studies in eucaryotic cells (mainly animals and yeast) indicate that at least two DNA polymerases are involved in DNA replication at the level of the replication fork: DNA polymerase alpha, which is associated with DNA primase, is involved in the replication of the lagging strand; DNA polymerase delta, associated with an exonuclease activity, synthesizes the forward continuous DNA strand. Much less information exists concerning plant systems. Previous work from this laboratory provided preliminary evidence of an association between DNA polymerase B from wheat embryo and an exonucleolytic activity. In this paper, we present additional data on the biochemical properties of DNA polymerase B. An improved purification procedure described in this article has been developed. During all the purification steps the nuclease activity was associated with DNA polymerase activity. A biochemical study of this enzyme activity shows that it is an exonuclease which hydrolyses DNA in the 3' to 5' direction. Moreover, this exonuclease confers a proofreading function to DNA polymerase B. Comparison of DNA polymerase B properties (template specificity, sensitivity to DNA replication inhibitors like aphidicolin and butyl-phenyl dGTP, copurification of DNA polymerase and exonuclease activities) with those of animal DNA polymerase delta indicates that these enzymes share many common features. To our knowledge, this is the first report of DNA polymerase delta in higher plants.
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Affiliation(s)
- M C Richard
- Institut de Biochimie Cellulaire et Neurochimie, Bordeaux, France
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18
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Bambara RA, Jessee CB. Properties of DNA polymerases delta and epsilon, and their roles in eukaryotic DNA replication. BIOCHIMICA ET BIOPHYSICA ACTA 1991; 1088:11-24. [PMID: 1846563 DOI: 10.1016/0167-4781(91)90147-e] [Citation(s) in RCA: 92] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- R A Bambara
- Department of Biochemistry, University of Rochester, NY
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19
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Affiliation(s)
- F W Perrino
- Joseph Gottstein Memorial Cancer Research Laboratory, Department of Pathology, University of Washington, Seattle 98195
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20
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Abstract
The identities and precise roles of the DNA polymerase(s) involved in mammalian cell DNA replication are uncertain. Circumstantial evidence suggests that DNA polymerase alpha and at least one form of DNA polymerase delta, that which is stimulated by Proliferating Cell Nuclear Antigen, catalyze mammalian cell replicative DNA synthesis. Further, the in vitro properties of polymerases alpha and delta suggest a model for their coordinate action at the replication fork. The present paper summarizes the current status of DNA polymerases alpha and delta in DNA replication, and describes newly available approaches to the study of those enzymes.
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Affiliation(s)
- R V Talanian
- Department of Pharmacology, University of Massachusetts Medical School, Worcester 01655
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21
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Bender MA. Time course of enhancement of chromosomal aberration production in human lymphocytes by post-treatment with aphidicolin following X-irradiation in G2. Mutat Res 1989; 213:175-83. [PMID: 2503716 DOI: 10.1016/0027-5107(89)90149-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- M A Bender
- Medical Department, Brookhaven National Laboratory, Upton, NY 11973
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22
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Yasui W, Ryoji M. Characterization of early DNA synthesis in Xenopus eggs after injection of circular plasmid DNA. Nucleic Acids Res 1989; 17:3709-23. [PMID: 2734101 PMCID: PMC317852 DOI: 10.1093/nar/17.10.3709] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Circular plasmid DNA is known to replicate when injected into unfertilized eggs of Xenopus laevis. We characterized early DNA synthesis which precedes the replication. Incorporation of a radioactive precursor into covalent closed circular DNA becomes detectable as early as 2 minutes after injection. Judging from the sensitivity to aphidicolin, replicative DNA polymerase alpha or delta is involved in this reaction. However, analysis of density-labeled product as well as detection of newly synthesized, unmethylated strands by restriction endonuclease DpnI digestion, both indicated that most if not all, of the synthesized DNA is present as short repair-like patches in the injected DNA molecules. They are present randomly in all the HaeIII fragments of injected DNA, and transcriptional activation of the 5S RNA gene inserted in the plasmid does not affect the distribution. Only a minor fraction of injected DNA is utilized for this reaction, and 12% of such DNA molecules are further chased into replicated progeny DNA. This efficiency of replication is nearly the same as that of bulk injected DNA which has not been subjected to the early DNA synthesis. We concluded that, despite the common use of replicative DNA polymerase, the early DNA synthesis and the subsequent DNA replication are mutually independent processes.
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Affiliation(s)
- W Yasui
- Department of Molecular and Experimental Medicine, Scripps Clinic and Research Foundation, La Jolla, CA 92037
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23
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Involvement of proliferating cell nuclear antigen (cyclin) in DNA replication in living cells. Mol Cell Biol 1989. [PMID: 2564636 DOI: 10.1128/mcb.9.1.57] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Proliferating cell nuclear antigen (PCNA) (also called cyclin) is known to stimulate the activity of DNA polymerase delta but not the other DNA polymerases in vitro. We injected a human autoimmune antibody against PCNA into unfertilized eggs of Xenopus laevis and examined the effects of this antibody on the replication of injected plasmid DNA as well as egg chromosomes. The anti-PCNA antibody inhibited plasmid replication by up to 67%, demonstrating that PCNA is involved in plasmid replication in living cells. This result further implies that DNA polymerase delta is necessary for plasmid replication in vivo. Anti-PCNA antibody alone did not block plasmid replication completely, but the residual replication was abolished by coinjection of a monoclonal antibody against DNA polymerase alpha. Anti-DNA polymerase alpha alone inhibited plasmid replication by 63%. Thus, DNA polymerase alpha is also required for plasmid replication in this system. In similar studies on the replication of egg chromosomes, the inhibition by anti-PCNA antibody was only 30%, while anti-DNA polymerase alpha antibody blocked 73% of replication. We concluded that the replication machineries of chromosomes and plasmid differ in their relative content of DNA polymerase delta. In addition, we obtained evidence through the use of phenylbutyl deoxyguanosine, an inhibitor of DNA polymerase alpha, that the structure of DNA polymerase alpha holoenzyme for chromosome replication is significantly different from that for plasmid replication.
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24
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Zuber M, Tan EM, Ryoji M. Involvement of proliferating cell nuclear antigen (cyclin) in DNA replication in living cells. Mol Cell Biol 1989; 9:57-66. [PMID: 2564636 PMCID: PMC362145 DOI: 10.1128/mcb.9.1.57-66.1989] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Proliferating cell nuclear antigen (PCNA) (also called cyclin) is known to stimulate the activity of DNA polymerase delta but not the other DNA polymerases in vitro. We injected a human autoimmune antibody against PCNA into unfertilized eggs of Xenopus laevis and examined the effects of this antibody on the replication of injected plasmid DNA as well as egg chromosomes. The anti-PCNA antibody inhibited plasmid replication by up to 67%, demonstrating that PCNA is involved in plasmid replication in living cells. This result further implies that DNA polymerase delta is necessary for plasmid replication in vivo. Anti-PCNA antibody alone did not block plasmid replication completely, but the residual replication was abolished by coinjection of a monoclonal antibody against DNA polymerase alpha. Anti-DNA polymerase alpha alone inhibited plasmid replication by 63%. Thus, DNA polymerase alpha is also required for plasmid replication in this system. In similar studies on the replication of egg chromosomes, the inhibition by anti-PCNA antibody was only 30%, while anti-DNA polymerase alpha antibody blocked 73% of replication. We concluded that the replication machineries of chromosomes and plasmid differ in their relative content of DNA polymerase delta. In addition, we obtained evidence through the use of phenylbutyl deoxyguanosine, an inhibitor of DNA polymerase alpha, that the structure of DNA polymerase alpha holoenzyme for chromosome replication is significantly different from that for plasmid replication.
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Affiliation(s)
- M Zuber
- W. M. Keck Autoimmune Disease Center, La Jolla, California
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25
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Burgers PM. Eukaryotic DNA polymerases alpha and delta: conserved properties and interactions, from yeast to mammalian cells. PROGRESS IN NUCLEIC ACID RESEARCH AND MOLECULAR BIOLOGY 1989; 37:235-80. [PMID: 2505329 DOI: 10.1016/s0079-6603(08)60700-x] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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26
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Dresler SL, Frattini MG. Analysis of butylphenyl-guanine, butylphenyl-deoxyguanosine, and butylphenyl-deoxyguanosine triphosphate inhibition of DNA replication and ultraviolet-induced DNA repair synthesis using permeable human fibroblasts. Biochem Pharmacol 1988; 37:1033-7. [PMID: 3355581 DOI: 10.1016/0006-2952(88)90506-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The purine base and nucleoside analogues N2-(p-n-butylphenyl)-guanine (BuPh-Gua) and N2-(p-n-butylphenyl)-2'-deoxyguanosine (BuPh-dGuo) are strong inhibitors of isolated mammalian DNA polymerase alpha, but are less potent that expected as inhibitors of DNA replication in intact cultured cells [G. E. Wright, L. W. Dudycz, Z. Kazimierczuk, N. C. Brown and N. N. Khan, J. med. Chem. 30, 109 (1987)]. The mechanistic basis for these observations was explored using permeable human fibroblasts. DNA replication in the permeable cells was inhibited only slightly by BuPh-Gua and BuPh-dGuo at 100 microM, the highest concentration which could be attained. Similar results were obtained for ultraviolet-induced DNA repair synthesis, a process which is though to involve the same DNA polymerase as replication. More detailed studies were performed using the corresponding nucleotide analogue, N2-(p-n-butylphenyl)-2'-deoxyguanosine-5'-triphosphate (BuPh-dGTP), which is much more water-soluble than the base and nucleoside. The apparent Ki values for BuPh-dGTP inhibition of both replication and ultraviolet-induced repair synthesis in permeable cells were approximately 3 microM. These values are several hundred-fold greater than the apparent Ki for BuPh-dGTP inhibition of isolated human DNA polymerase alpha, which is approximately 10 nM. We conclude that BuPh-Gua and BuPh-dGuo are poor inhibitors of DNA replication in intact cells not because of permeability barriers, but because, unlike polymerase alpha, cellular DNA synthesis is relatively insensitive to this group of inhibitors. These results suggest that polymerase alpha may not be a good general model for predicting the potency of base, deoxyribonucleoside and deoxyribonucleotide analogues as inhibitors of mammalian cellular DNA replication. The fact that the permeable cell systems accurately reflect the relative insensitivity to butylphenyl-guanine derivatives of mammalian DNA replication suggests that permeable cells may be useful tools in future studies of base and nucleoside analogues.
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Affiliation(s)
- S L Dresler
- Department of Pathology, Washington University School of Medicine, St. Louis, MO 63110
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27
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Kaiserman HB, Benbow RM. Characterization of a stable, major DNA polymerase alpha species devoid of DNA primase activity. Nucleic Acids Res 1987; 15:10249-65. [PMID: 3697091 PMCID: PMC339942 DOI: 10.1093/nar/15.24.10249] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
We have purified from Xenopus laevis ovaries a major DNA polymerase alpha species that lacked DNA primase activity. This primase-devoid DNA polymerase alpha species exhibited the same sensitivity as the DNA polymerase DNA primase alpha to BuAdATP and BuPdGTP, nucleotide analogs capable of distinguishing between DNA polymerase delta and DNA polymerase DNA primase alpha. The primase-devoid DNA polymerase alpha species also lacked significant nuclease activity indicative of the alpha-like (rather than delta-like) nature of the DNA polymerase. Using a poly(dT) template, the primase-devoid DNA polymerase alpha species elongated an oligo(rA10) primer up to 51-fold more effectively than an oligo(dA10) primer. In direct contrast, the DNA polymerase DNA primase alpha complex showed only a 4.6-fold preference for oligoribonucleotide primers at the same template/primer ratio. The catalytic differences between the two DNA polymerase alpha species were most dramatic at a template/primer ratio of 300. The primase-devoid DNA polymerase alpha species was found at high levels throughout oocyte and embryonic development. This suggests that the primase-devoid DNA polymerase alpha species could play a physiological role during DNA chain elongation in vivo, even if it is chemically related to DNA polymerase DNA primase alpha.
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Affiliation(s)
- H B Kaiserman
- Department of Zoology, Iowa State University, Ames 50011-3223
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28
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Decker RS, Yamaguchi M, Possenti R, Bradley MK, DePamphilis ML. In vitro initiation of DNA replication in simian virus 40 chromosomes. J Biol Chem 1987. [DOI: 10.1016/s0021-9258(18)61044-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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29
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Zhang SJ, Lee MY. Biochemical characterization and development of DNA polymerases alpha and delta in the neonatal rat heart. Arch Biochem Biophys 1987; 252:24-31. [PMID: 3813535 DOI: 10.1016/0003-9861(87)90004-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The ontogeny of DNA polymerase activity in the neonatal rat heart was studied. The DNA polymerase activities in rat heart extracts were identified as DNA polymerase alpha and DNA polymerase delta activities by their purification and characterization, by the use of a specific inhibitor (BuAdATP), and by a specific monoclonal antibody against DNA polymerase alpha. Using these inhibitors, it was shown that the two activities declined in parallel during the maturation and terminal differentiation of the heart.
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30
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Crute JJ, Wahl AF, Bambara RA. Purification and characterization of two new high molecular weight forms of DNA polymerase delta. Biochemistry 1986; 25:26-36. [PMID: 3954990 DOI: 10.1021/bi00349a005] [Citation(s) in RCA: 125] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Two high molecular weight DNA polymerases, which we have designated delta I and delta II, have been purified from calf thymus tissue. Using Bio Rex-70, DEAE-Sephadex A-25, and DNA affinity resin chromatography followed by sucrose gradient sedimentation, we purified DNA polymerase delta I 1400-fold to a specific activity of 10 000 nmol of nucleotide incorporated h-1 mg-1, and DNA polymerase delta II was purified 4100-fold to a final specific activity of 30 000 nmol of nucleotide incorporated h-1 mg-1. The native molecular weights of DNA polymerase delta I and DNA polymerase delta II are 240 000 and 290 000, respectively. Both enzymes have similarities to other purified delta-polymerases previously reported in their ability to degrade single-stranded DNA in a 3' to 5' direction, affinity for an AMP-hexane-agarose matrix, high activity on poly(dA) X oligo(dT) template, and relative resistance to the polymerase alpha inhibitors N2-(p-n-butylphenyl)dATP and N2-(p-n-butylphenyl)dGTP. These two forms of DNA polymerase delta also share several common features with alpha-type DNA polymerases. Both calf DNA polymerase delta I and DNA polymerase delta II are similar to calf DNA polymerase alpha in molecular weight, are inhibited by the alpha-polymerase inhibitors N-ethylmaleimide and aphidicolin, contain an active DNA-dependent RNA polymerase or primase activity, display a similar extent of processive DNA synthesis, and are stimulated by millimolar concentrations of ATP. We propose that calf DNA polymerase delta I, which also has a template specificity essentially identical with that of calf DNA polymerase alpha, could be an exonuclease-containing form of a DNA replicative enzyme.
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31
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Lee MY, Toomey NL, Wright GE. Differential inhibition of human placental DNA polymerases delta and alpha by BuPdGTP and BuAdATP. Nucleic Acids Res 1985; 13:8623-30. [PMID: 3936020 PMCID: PMC322157 DOI: 10.1093/nar/13.23.8623] [Citation(s) in RCA: 72] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The p-n-butylphenyl- and p-n-butylanilino- substituted analogs of dGTP and dATP, respectively, were tested as inhibitors of purified human placental DNA polymerases alpha and delta. It was observed that DNA polymerase alpha activity was potently inhibited by these analogs with I0.5 values as low as the nanomolar range, whereas DNA polymerase delta activity was poorly inhibited, with I0.5 values of ca. 100 micromolar. These results argue for a distinct identity of these two enzymes, and demonstrate the usefulness of these analogs as probes of DNA polymerase structures. In addition, these analogs provide a rapid method for the discrimination of the two enzyme activities and a means for the selective assay of DNA polymerase delta. Aphidicolin inhibited both DNA polymerases.
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32
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Abstract
DNA polymerases alpha and delta from bone marrow are similar in many respects, the major known difference being the exonuclease activity of delta. Differential inhibitors of alpha and delta have been sought to assist in their functional and physical separation. Butylphenyl deoxyguanosine triphosphate is one. It effectively inhibits alpha at less than 1 microM concentration, whereas more than 100 microM is required to similarly inhibit delta. Another is the monoclonal antibody, SJK 132-20, which neutralizes the polymerase activity of alpha but not delta. These differential inhibitors further define alpha and delta as separate categories of eukaryotic DNA polymerase and promise to facilitate the study of both.
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