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Perlo V, Furtado A, Botha FC, Margarido GRA, Hodgson‐Kratky K, Choudhary H, Gladden J, Simmons B, Henry RJ. Transcriptome and metabolome integration in sugarcane through culm development. Food Energy Secur 2022. [DOI: 10.1002/fes3.421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Affiliation(s)
- Virginie Perlo
- Queensland Alliance for Agriculture and Food Innovation University of Queensland Brisbane Australia
| | - Agnelo Furtado
- Queensland Alliance for Agriculture and Food Innovation University of Queensland Brisbane Australia
| | - Frederik C. Botha
- Queensland Alliance for Agriculture and Food Innovation University of Queensland Brisbane Australia
| | - Gabriel R. A. Margarido
- Departamento de Genética, Escola Superior de Agricultura “Luiz de Queiroz” Universidade de São Paulo São Paulo Brazil
| | - Katrina Hodgson‐Kratky
- Queensland Alliance for Agriculture and Food Innovation University of Queensland Brisbane Australia
| | - Hemant Choudhary
- Joint BioEnergy Institute Emeryville CA USA
- Sandia National Laboratories Livermore CA USA
| | - John Gladden
- Joint BioEnergy Institute Emeryville CA USA
- Sandia National Laboratories Livermore CA USA
| | | | - Robert J. Henry
- Queensland Alliance for Agriculture and Food Innovation University of Queensland Brisbane Australia
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Takatsuka H, Shibata A, Umeda M. Genome Maintenance Mechanisms at the Chromatin Level. Int J Mol Sci 2021; 22:ijms221910384. [PMID: 34638727 PMCID: PMC8508675 DOI: 10.3390/ijms221910384] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 09/22/2021] [Accepted: 09/24/2021] [Indexed: 12/12/2022] Open
Abstract
Genome integrity is constantly threatened by internal and external stressors, in both animals and plants. As plants are sessile, a variety of environment stressors can damage their DNA. In the nucleus, DNA twines around histone proteins to form the higher-order structure “chromatin”. Unraveling how chromatin transforms on sensing genotoxic stress is, thus, key to understanding plant strategies to cope with fluctuating environments. In recent years, accumulating evidence in plant research has suggested that chromatin plays a crucial role in protecting DNA from genotoxic stress in three ways: (1) changes in chromatin modifications around damaged sites enhance DNA repair by providing a scaffold and/or easy access to DNA repair machinery; (2) DNA damage triggers genome-wide alterations in chromatin modifications, globally modulating gene expression required for DNA damage response, such as stem cell death, cell-cycle arrest, and an early onset of endoreplication; and (3) condensed chromatin functions as a physical barrier against genotoxic stressors to protect DNA. In this review, we highlight the chromatin-level control of genome stability and compare the regulatory systems in plants and animals to find out unique mechanisms maintaining genome integrity under genotoxic stress.
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Affiliation(s)
- Hirotomo Takatsuka
- School of Biological Science and Technology, College of Science and Engineering, Kanazawa University, Kakuma-Machi, Kanazawa 920-1192, Japan;
| | - Atsushi Shibata
- Signal Transduction Program, Gunma University Initiative for Advanced Research (GIAR), 3-39-22, Showa-Machi, Maebashi 371-8511, Japan;
| | - Masaaki Umeda
- Graduate School of Science and Technology, Nara Institute of Science and Technology, Ikoma 630-0192, Japan
- Correspondence:
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Khan MS, Kumar S, Singh RK, Singh J, Duttamajumder SK, Kapur R. Characterization of leaf transcriptome, development and utilization of unigenes-derived microsatellite markers in sugarcane ( Saccharum sp. hybrid). PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS : AN INTERNATIONAL JOURNAL OF FUNCTIONAL PLANT BIOLOGY 2018; 24:665-682. [PMID: 30042621 PMCID: PMC6041238 DOI: 10.1007/s12298-018-0563-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Revised: 05/14/2018] [Accepted: 05/22/2018] [Indexed: 06/08/2023]
Abstract
Sugarcane (Saccharum species hybrid) is the major source of sugar (> 80% sugar) in the world and is cultivated in more than 115 countries. It has recently gained attention as a source of biofuel (ethanol). Due to genomic complexity, the development of new genomic resources is imperative in understanding the gene regulation and function, and to fine tune the genetic improvement of sugarcane. In this study, a cDNA library was constructed from mature leaves so as to develop ESTs resources which were further compared with nucleotide and protein databases to explore the functional identity of sugarcane genes. The non-redundant ESTs (unigenes) were categorized into 18 metabolic functions. The major categories were bioenergetics and photosynthesis (4%), cell metabolism (5%), development related protein (3%), membrane-related, mobile genetic elements (5%), signal transduction (2%), DNA (1%), RNA (1%) and protein (2%) metabolism, other metabolic processes (3%), transcription factors (1%), transport (4%) and proteins related to stress/defense (4%). From 540 unique ESTs, 212 simple sequence repeats were identified, of which 206 were from 463 singlets and six were mined from 77 contig sequences. A total of 540 unique EST sequences were used for SSR search of which 97 (17.9%) contained specified SSR motifs, generating 212 unique SSRs. The genes characterized in this study and the EST-derived microsatellite markers identified from the cDNA library will enrich genomic resources for association- and linkage-mapping studies in sugarcane.
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Affiliation(s)
- Mohammad Suhail Khan
- ICAR-Indian Institute of Sugarcane Research, Raibareli Road, P.O. Dilkusha, Lucknow, U.P. 226002 India
| | - Sanjeev Kumar
- ICAR-Indian Institute of Sugarcane Research, Raibareli Road, P.O. Dilkusha, Lucknow, U.P. 226002 India
| | - Ram Kewal Singh
- ICAR-Indian Institute of Sugarcane Research, Raibareli Road, P.O. Dilkusha, Lucknow, U.P. 226002 India
- Present Address: Division of Crop Science, Indian Council of Agricultural Research, Dr. Rajendra Prasad Road, Krishi Bhawan, New Delhi, 110 001 India
| | - Jyotsnendra Singh
- ICAR-Indian Institute of Sugarcane Research, Raibareli Road, P.O. Dilkusha, Lucknow, U.P. 226002 India
| | | | - Raman Kapur
- ICAR-Indian Institute of Sugarcane Research, Raibareli Road, P.O. Dilkusha, Lucknow, U.P. 226002 India
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Manova V, Gruszka D. DNA damage and repair in plants - from models to crops. FRONTIERS IN PLANT SCIENCE 2015; 6:885. [PMID: 26557130 PMCID: PMC4617055 DOI: 10.3389/fpls.2015.00885] [Citation(s) in RCA: 168] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2015] [Accepted: 10/05/2015] [Indexed: 05/17/2023]
Abstract
The genomic integrity of every organism is constantly challenged by endogenous and exogenous DNA-damaging factors. Mutagenic agents cause reduced stability of plant genome and have a deleterious effect on development, and in the case of crop species lead to yield reduction. It is crucial for all organisms, including plants, to develop efficient mechanisms for maintenance of the genome integrity. DNA repair processes have been characterized in bacterial, fungal, and mammalian model systems. The description of these processes in plants, in contrast, was initiated relatively recently and has been focused largely on the model plant Arabidopsis thaliana. Consequently, our knowledge about DNA repair in plant genomes - particularly in the genomes of crop plants - is by far more limited. However, the relatively small size of the Arabidopsis genome, its rapid life cycle and availability of various transformation methods make this species an attractive model for the study of eukaryotic DNA repair mechanisms and mutagenesis. Moreover, abnormalities in DNA repair which proved to be lethal for animal models are tolerated in plant genomes, although sensitivity to DNA damaging agents is retained. Due to the high conservation of DNA repair processes and factors mediating them among eukaryotes, genes and proteins that have been identified in model species may serve to identify homologous sequences in other species, including crop plants, in which these mechanisms are poorly understood. Crop breeding programs have provided remarkable advances in food quality and yield over the last century. Although the human population is predicted to "peak" by 2050, further advances in yield will be required to feed this population. Breeding requires genetic diversity. The biological impact of any mutagenic agent used for the creation of genetic diversity depends on the chemical nature of the induced lesions and on the efficiency and accuracy of their repair. More recent targeted mutagenesis procedures also depend on host repair processes, with different pathways yielding different products. Enhanced understanding of DNA repair processes in plants will inform and accelerate the engineering of crop genomes via both traditional and targeted approaches.
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Affiliation(s)
- Vasilissa Manova
- Department of Molecular Genetics, Institute of Plant Physiology and Genetics, Bulgarian Academy of SciencesSofia
| | - Damian Gruszka
- Department of Genetics, Faculty of Biology and Environment Protection, University of SilesiaKatowice, Poland
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Gruszka D, Marzec M, Szarejko I. The barley EST DNA Replication and Repair Database (bEST-DRRD) as a tool for the identification of the genes involved in DNA replication and repair. BMC PLANT BIOLOGY 2012; 12:88. [PMID: 22697361 PMCID: PMC3410793 DOI: 10.1186/1471-2229-12-88] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Accepted: 06/14/2012] [Indexed: 05/29/2023]
Abstract
BACKGROUND The high level of conservation of genes that regulate DNA replication and repair indicates that they may serve as a source of information on the origin and evolution of the species and makes them a reliable system for the identification of cross-species homologs. Studies that had been conducted to date shed light on the processes of DNA replication and repair in bacteria, yeast and mammals. However, there is still much to be learned about the process of DNA damage repair in plants. DESCRIPTION These studies, which were conducted mainly using bioinformatics tools, enabled the list of genes that participate in various pathways of DNA repair in Arabidopsis thaliana (L.) Heynh to be outlined; however, information regarding these mechanisms in crop plants is still very limited. A similar, functional approach is particularly difficult for a species whose complete genomic sequences are still unavailable. One of the solutions is to apply ESTs (Expressed Sequence Tags) as the basis for gene identification. For the construction of the barley EST DNA Replication and Repair Database (bEST-DRRD), presented here, the Arabidopsis nucleotide and protein sequences involved in DNA replication and repair were used to browse for and retrieve the deposited sequences, derived from four barley (Hordeum vulgare L.) sequence databases, including the "Barley Genome version 0.05" database (encompassing ca. 90% of barley coding sequences) and from two databases covering the complete genomes of two monocot models: Oryza sativa L. and Brachypodium distachyon L. in order to identify homologous genes. Sequences of the categorised Arabidopsis queries are used for browsing the repositories, which are located on the ViroBLAST platform. The bEST-DRRD is currently used in our project during the identification and validation of the barley genes involved in DNA repair. CONCLUSIONS The presented database provides information about the Arabidopsis genes involved in DNA replication and repair, their expression patterns and models of protein interactions. It was designed and established to provide an open-access tool for the identification of monocot homologs of known Arabidopsis genes that are responsible for DNA-related processes. The barley genes identified in the project are currently being analysed to validate their function.
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Affiliation(s)
- Damian Gruszka
- Department of Genetics, Faculty of Biology and Environment Protection, University of Silesia, Jagiellonska 28, 40-032, Katowice, Poland
| | - Marek Marzec
- Department of Genetics, Faculty of Biology and Environment Protection, University of Silesia, Jagiellonska 28, 40-032, Katowice, Poland
| | - Iwona Szarejko
- Department of Genetics, Faculty of Biology and Environment Protection, University of Silesia, Jagiellonska 28, 40-032, Katowice, Poland
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Vonarx EJ, Tabone EK, Osmond MJ, Anderson HJ, Kunz BA. Arabidopsis homologue of human transcription factor IIH/nucleotide excision repair factor p44 can function in transcription and DNA repair and interacts with AtXPD. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2006; 46:512-21. [PMID: 16623910 DOI: 10.1111/j.1365-313x.2006.02705.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Eukaryotic general transcription factor (TF) IIH is composed of 10 proteins, seven of which are also required for nucleotide excision repair (NER) of UV radiation-induced DNA damage in human cells and yeast. Plant homologues of the human TFIIH subunits XPB and XPD that function in NER have been isolated but none has been shown to operate in transcription. Here we address the capabilities of Arabidopsis thaliana AtGTF2H2 and AtXPD, homologues of the essential interacting human/yeast TFIIH components p44/Ssl1 and XPD/Rad3, respectively. Expression of AtGTF2H2 or AtXPD cDNAs in yeast ssl1 or rad3 mutants temperature-sensitive for growth due to thermolabile transcription of mRNA restored growth and so transcription at the non-permissive temperature. AtGTF2H2 also complemented the NER deficiency of the corresponding yeast mutant, as measured by full recovery of UV resistance, whereas AtXPD did not despite being necessary for NER in Arabidopsis. UV treatment did not upregulate transcription of AtGTF2H2 or AtXPD in Arabidopsis. Suppression of a yeast translation initiation defect by the ssl1-1 mutation was prevented by expression of AtGTF2H2. Deletion of SSL1 in a yeast strain expressing AtGTF2H2 did not affect growth or confer UV sensitivity, demonstrating that AtGTF2H2 can perform all essential transcription functions and UV damage repair duties of Ssl1 in its absence. Furthermore, AtGTF2H2 interacted with AtXPD and yeast Rad3, and AtXPD also interacted with yeast Ssl1 in two-hybrid assays. Our results indicate that AtGTF2H2 can act in transcription and NER, and suggest that it participates in both processes in Arabidopsis as part of TFIIH.
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Affiliation(s)
- Edward J Vonarx
- School of Life and Environmental Sciences, Deakin University, Geelong, Victoria 3217, Australia
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Kunz BA, Cahill DM, Mohr PG, Osmond MJ, Vonarx EJ. Plant responses to UV radiation and links to pathogen resistance. INTERNATIONAL REVIEW OF CYTOLOGY 2006; 255:1-40. [PMID: 17178464 DOI: 10.1016/s0074-7696(06)55001-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Increased incident ultraviolet (UV) radiation due to ozone depletion has heightened interest in plant responses to UV because solar UV wavelengths can reduce plant genome stability, growth, and productivity. These detrimental effects result from damage to cell components including nucleic acids, proteins, and membrane lipids. As obligate phototrophs, plants must counter the onslaught of cellular damage due to prolonged exposure to sunlight. They do so by attenuating the UV dose received through accumulation of UV-absorbing secondary metabolites, neutralizing reactive oxygen species produced by UV, monomerizing UV-induced pyrimidine dimers by photoreactivation, extracting UV photoproducts from DNA via nucleotide excision repair, and perhaps transiently tolerating the presence of DNA lesions via replicative bypass of the damage. The signaling mechanisms controlling these responses suggest that UV exposure also may be beneficial to plants by increasing cellular immunity to pathogens. Indeed, pathogen resistance can be enhanced by UV treatment, and recent experiments suggest DNA damage and its processing may have a role.
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Affiliation(s)
- Bernard A Kunz
- School of Life and Environmental Sciences, Deakin University, Geelong, Victoria 3217, Australia
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Kunz BA, Anderson HJ, Osmond MJ, Vonarx EJ. Components of nucleotide excision repair and DNA damage tolerance in Arabidopsis thaliana. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2005; 45:115-27. [PMID: 15645454 DOI: 10.1002/em.20094] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
As obligate phototrophs, and despite shielding strategies, plants sustain DNA damage caused by UV radiation in sunlight. By inhibiting DNA replication and transcription, such damage may contribute to the detrimental effects of UV radiation on the growth, productivity, and genetic stability of higher plants. However, there is evidence that plants can reverse UV-induced DNA damage by photoreactivation or remove it via nucleotide excision repair. In addition, plants may have mechanisms for tolerating UV photoproducts as a means of avoiding replicative arrest. Recently, phenotypic characterization of plant mutants, functional complementation studies, and cDNA analysis have implicated genes isolated from the model plant Arabidopsis thaliana in nucleotide excision repair or tolerance of UV-induced DNA damage. Here, we briefly review features of these processes in human cells, collate information on Arabidopsis homologs of the relevant genes, and summarize the experimental findings that link certain of these plant genes to nucleotide excision repair or damage tolerance.
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Affiliation(s)
- Bernard A Kunz
- School of Biological and Chemical Sciences, Deakin University, Geelong, Victoria, Australia.
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Morgante PG, Berra CM, Nakabashi M, Costa RMA, Menck CFM, Van Sluys MA. Functional XPB/RAD25 redundancy in Arabidopsis genome: characterization of AtXPB2 and expression analysis. Gene 2004; 344:93-103. [PMID: 15656976 DOI: 10.1016/j.gene.2004.10.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2004] [Revised: 09/24/2004] [Accepted: 10/05/2004] [Indexed: 11/20/2022]
Abstract
The xeroderma pigmentosum complementation group B (XPB) protein is involved in both DNA repair and transcription in human cells. It is a component of the transcription factor IIH (TFIIH) and is responsible for DNA helicase activity during nucleotide (nt) excision repair (NER). Its high evolutionary conservation has allowed identification of homologous proteins in different organisms, including plants. In contrast to other organisms, Arabidopsis thaliana harbors a duplication of the XPB orthologue (AtXPB1 and AtXPB2), and the proteins encoded by the duplicated genes are very similar (95% amino acid identity). Complementation assays in yeast rad25 mutant strains suggest the involvement of AtXPB2 in DNA repair, as already shown for AtXPB1, indicating that these proteins may be functionally redundant in the removal of DNA lesions in A. thaliana. Although both genes are expressed in a constitutive manner during the plant life cycle, Northern blot analyses suggest that light modulates the expression level of both XPB copies, and transcript levels increase during early stages of development. Considering the high similarity between AtXPB1 and AtXPB2 and that both of predicted proteins may act in DNA repair, it is possible that this duplication may confer more flexibility and resistance to DNA damaging agents in thale cress.
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Affiliation(s)
- Patrícia G Morgante
- Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, Rua do Matão 277, Cidade Universitária, São Paulo, 05508-900, SP, Brazil
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Liu Z, Hong SW, Escobar M, Vierling E, Mitchell DL, Mount DW, Hall JD. Arabidopsis UVH6, a homolog of human XPD and yeast RAD3 DNA repair genes, functions in DNA repair and is essential for plant growth. PLANT PHYSIOLOGY 2003; 132:1405-14. [PMID: 12857822 PMCID: PMC167080 DOI: 10.1104/pp.103.021808] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2003] [Revised: 03/30/2003] [Accepted: 04/17/2003] [Indexed: 05/18/2023]
Abstract
To evaluate the genetic control of stress responses in Arabidopsis, we have analyzed a mutant (uvh6-1) that exhibits increased sensitivity to UV light, a yellow-green leaf coloration, and mild growth defects. We have mapped the uvh6-1 locus to chromosome I and have identified a candidate gene, AtXPD, within the corresponding region. This gene shows sequence similarity to the human (Homo sapiens) XPD and yeast (Saccharomyces cerevisiae) RAD3 genes required for nucleotide excision repair. We propose that UVH6 is equivalent to AtXPD because uvh6-1 mutants carry a mutation in a conserved residue of AtXPD and because transformation of uvh6-1 mutants with wild-type AtXPD DNA suppresses both UV sensitivity and other defective phenotypes. Furthermore, the UVH6/AtXPD protein appears to play a role in repair of UV photoproducts because the uvh6-1 mutant exhibits a moderate defect in the excision of UV photoproducts. This defect is also suppressed by transformation with UVH6/AtXPD DNA. We have further identified a T-DNA insertion in the UVH6/AtXPD gene (uvh6-2). Plants carrying homozygous insertions were not detected in analyses of progeny from plants heterozygous for the insertion. Thus, homozygous insertions appear to be lethal. We conclude that the UVH6/AtXPD gene is required for UV resistance and is an essential gene in Arabidopsis.
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Affiliation(s)
- Zongrang Liu
- Departments of Molecular and Cellular Biology, University of Arizona, Tucson, Arizona 85721, USA
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Hays JB. Arabidopsis thaliana, a versatile model system for study of eukaryotic genome-maintenance functions. DNA Repair (Amst) 2002; 1:579-600. [PMID: 12509283 DOI: 10.1016/s1568-7864(02)00093-9] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Abstract
The genome of the model plant Arabidopsis thaliana encodes many orthologs of human genome-maintenance proteins, and in several important cases plant DNA repair and mutation-antagonism functions resemble their mammalian counterparts more closely than do those of established microbial models. These orthologs, in conjunction with the powerful tools now available for work with Arabidopsis and the practical advantages of its small size and rapid life cycle, now make it an attractive model system for study of eukaryotic DNA repair and mutagenesis. Already, null mutations that inactivate proteins involved in repair of DNA double-strand breaks or in DNA translesion synthesis and are lethal in mice have proved to be tolerated by plants. This review compares in some detail the genome-maintenance activities encoded by plants, mammals and microbes, and describes important Arabidopsis tools and life cycle characteristics. It concludes with selected examples that illustrate Arabidopsis advantages and/or reveal new insights into genome-maintenance functions of general interest.
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Affiliation(s)
- John B Hays
- Department of Environmental and Molecular Toxicology, 1007 ALS Building, Oregon State University, Corvallis, OR 97331-7301, USA.
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Abstract
Oxidative stress response in plants is still poorly understood in comparison with the correspondent phenomenon in bacteria, yeast and mammals. For instance, nitric oxide is assumed to play various roles in plants although no nitric oxide synthase gene has yet been isolated. This research reports the results of a search of the sugarcane expressed sequence tag (SUCEST) database for homologous sequences involved in the oxidative stress response. I have not found any gene similar to nitric oxide synthase in the SUCEST database although an alternative pathway for nitric oxide synthesis was proposed. I have also found several genes involved in antioxidant defense, e.g. metal chelators, low molecular weight compounds, antioxidant enzymes and repair systems. Ascorbate (vitamin C) is a key antioxidant in plants because it reaches high concentrations in cells and is a substrate for ascorbate peroxidase, an enzyme that I found in different isoforms in the SUCEST database. I also found many enzymes involved in the biosynthesis of low molecular weight antioxidants, which may be potential targets for genetic manipulation. The engineering of plants for increased vitamin C and E production may lead to improvements in the nutritional value and stress tolerance of sugarcane. The components of the antioxidant defense system interact and their synthesis is probably closely regulated. Transcription factors involved in regulation of the oxidative stress response in bacteria, yeast and mammals differ considerably among themselves and when I used them to search the SUCEST database only genes with weak similarities were found, suggesting that these transcription regulators are not very conserved. The involvement of reactive oxygen species and antioxidants in plant defense against pathogens is also discussed.
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Lima W, Medina-Silva R, Galhardo R, Menck C. Distribution of DNA repair-related ESTs in sugarcane. Genet Mol Biol 2001. [DOI: 10.1590/s1415-47572001000100019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
DNA repair pathways are necessary to maintain the proper genomic stability and ensure the survival of the organism, protecting it against the damaging effects of endogenous and exogenous agents. In this work, we made an analysis of the expression patterns of DNA repair-related genes in sugarcane, by determining the EST (expressed sequence tags) distribution in the different cDNA libraries of the SUCEST transcriptome project. Three different pathways - photoreactivation, base excision repair and nucleotide excision repair - were investigated by employing known DNA repair proteins as probes to identify homologous ESTs in sugarcane, by means of computer similarity search. The results showed that DNA repair genes may have differential expressions in tissues, depending on the pathway studied. These in silico data provide important clues on the potential variation of gene expression, to be confirmed by direct biochemical analysis.
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