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Sloan DB, Broz AK, Kuster SA, Muthye V, Peñafiel-Ayala A, Marron JR, Lavrov DV, Brieba LG. Expansion of the MutS Gene Family in Plants. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.17.603841. [PMID: 39071318 PMCID: PMC11275761 DOI: 10.1101/2024.07.17.603841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
The MutS gene family is distributed across the tree of life and is involved in recombination, DNA repair, and protein translation. Multiple evolutionary processes have expanded the set of MutS genes in plants relative to other eukaryotes. Here, we investigate the origins and functions of these plant-specific genes. Land plants, green algae, red algae, and glaucophytes share cyanobacterial-like MutS1 and MutS2 genes that presumably were gained via plastid endosymbiotic gene transfer. MutS1 was subsequently lost in some taxa, including seed plants, whereas MutS2 was duplicated in Viridiplantae (i.e., land plants and green algae) with widespread retention of both resulting paralogs. Viridiplantae also have two anciently duplicated copies of the eukaryotic MSH6 gene (i.e., MSH6 and MSH7) and acquired MSH1 via horizontal gene transfer - potentially from a nucleocytovirus. Despite sharing the same name, "plant MSH1" is not directly related to the gene known as MSH1 in some fungi and animals, which may be an ancestral eukaryotic gene acquired via mitochondrial endosymbiosis and subsequently lost in most eukaryotic lineages. There has been substantial progress in understanding the functions of MSH1 and MSH6/MSH7 in plants, but the roles of the cyanobacterial-like MutS1 and MutS2 genes remain uncharacterized. Known functions of bacterial homologs and predicted protein structures, including fusions to diverse nuclease domains, provide hypotheses about potential molecular mechanisms. Because most plant-specific MutS proteins are targeted to the mitochondria and/or plastids, the expansion of this family appears to have played a large role in shaping plant organelle genetics.
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Affiliation(s)
- Daniel B Sloan
- Department of Biology, Colorado State University, Fort Collins, CO, USA
| | - Amanda K Broz
- Department of Biology, Colorado State University, Fort Collins, CO, USA
| | - Shady A Kuster
- Department of Biology, Colorado State University, Fort Collins, CO, USA
- Cell and Molecular Biology Program, Colorado State University, Fort Collins, CO, USA
| | - Viraj Muthye
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Alejandro Peñafiel-Ayala
- Unidad de Genómica Avanzada, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Irapuato, Gto, México
| | - Jennifer R Marron
- Department of Biology, Colorado State University, Fort Collins, CO, USA
| | - Dennis V Lavrov
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA, USA
| | - Luis G Brieba
- Unidad de Genómica Avanzada, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Irapuato, Gto, México
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2
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Jiang L, Guo T, Song X, Jiang H, Lu M, Luo J, Rossi V, He Y. MSH7 confers quantitative variation in pollen fertility and boosts grain yield in maize. PLANT BIOTECHNOLOGY JOURNAL 2024; 22:1372-1386. [PMID: 38263872 PMCID: PMC11022798 DOI: 10.1111/pbi.14272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 11/15/2023] [Accepted: 12/08/2023] [Indexed: 01/25/2024]
Abstract
Fertile pollen is critical for the survival, fitness, and dispersal of flowering plants, and directly contributes to crop productivity. Extensive mutational screening studies have been carried out to dissect the genetic regulatory network determining pollen fertility, but we still lack fundamental knowledge about whether and how pollen fertility is controlled in natural populations. We used a genome-wide association study (GWAS) to show that ZmGEN1A and ZmMSH7, two DNA repair-related genes, confer natural variation in maize pollen fertility. Mutants defective in these genes exhibited abnormalities in meiotic or post-meiotic DNA repair, leading to reduced pollen fertility. More importantly, ZmMSH7 showed evidence of selection during maize domestication, and its disruption resulted in a substantial increase in grain yield for both inbred and hybrid. Overall, our study describes the first systematic examination of natural genetic effects on pollen fertility in plants, providing valuable genetic resources for optimizing male fertility. In addition, we find that ZmMSH7 represents a candidate for improvement of grain yield.
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Affiliation(s)
- Luguang Jiang
- National Maize Improvement Center of China, College of Agronomy and BiotechnologyChina Agricultural UniversityBeijingChina
| | - Ting Guo
- Institute of Genetics and Developmental Biology, Key Laboratory of Seed InnovationChinese Academy of SciencesBeijingChina
| | - Xinyuan Song
- Jilin Provincial Key Laboratory of Agricultural Biotechnology, Agro‐Biotechnology Research InstituteJilin Academy of Agricultural SciencesChangchunChina
| | - Huan Jiang
- National Maize Improvement Center of China, College of Agronomy and BiotechnologyChina Agricultural UniversityBeijingChina
| | - Minhui Lu
- Center for Crop Functional Genomics and Molecular BreedingChina Agricultural UniversityBeijingChina
| | - Jinhong Luo
- National Maize Improvement Center of China, College of Agronomy and BiotechnologyChina Agricultural UniversityBeijingChina
- Institute of Genetics and Developmental Biology, Key Laboratory of Seed InnovationChinese Academy of SciencesBeijingChina
| | - Vincenzo Rossi
- Council for Agricultural Research and EconomicsResearch Centre for Cereal and Industrial CropsBergamoItaly
| | - Yan He
- National Maize Improvement Center of China, College of Agronomy and BiotechnologyChina Agricultural UniversityBeijingChina
- Institute of Genetics and Developmental Biology, Key Laboratory of Seed InnovationChinese Academy of SciencesBeijingChina
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3
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Gonzalez V, Figueroa NR, Spampinato CP. Plant-specific environmental and developmental signals regulate the mismatch repair protein MSH6 in Arabidopsis thaliana. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2024; 342:112050. [PMID: 38401766 DOI: 10.1016/j.plantsci.2024.112050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 02/19/2024] [Accepted: 02/20/2024] [Indexed: 02/26/2024]
Abstract
The DNA mismatch repair (MMR) is a postreplicative system that guarantees genomic stability by correcting mispaired and unpaired nucleotides. In eukaryotic nuclei, MMR is initiated by the binding of heterodimeric MutS homologue (MSH) complexes to the DNA error or lesion. Among these proteins, MSH2-MSH6 is the most abundant heterodimer. Even though the MMR mechanism and proteins are highly conserved throughout evolution, physiological differences between species can lead to different regulatory features. Here, we investigated how light, sugar, and/or hormones modulate Arabidopsis thaliana MSH6 expression pattern. We first characterized the promoter region of MSH6. Phylogenetic shadowing revealed three highly conserved regions. These regions were analyzed by the generation of deletion constructs of the MSH6 full-length promoter fused to the β-glucuronidase (GUS) gene. Combined, our in silico and genetic analyses revealed that a 121-bp promoter fragment was necessary for MSH6 expression and contained potential cis-acting elements involved in light- and hormone-responsive gene expression. Accordingly, light exposure or sugar treatment of four-day old A. thaliana seedlings triggered an upregulation of MSH6 in shoot and root apical meristems. Appropriately, MSH6 was also induced by the stem cell inducer WUSCHEL. Further, the stimulatory effect of light was dependent on the presence of phyA. In addition, treatment of seedlings with auxin or cytokinin also caused an upregulation of MSH6 under darkness. Consistent with auxin signals, MSH6 expression was suppressed in the GATA23 RNAi line compared with the wild type. Our results provide evidence that endogenous factors and environmental signals controlling plant growth and development regulate the MSH6 protein in A. thaliana.
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Affiliation(s)
- Valentina Gonzalez
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario 2000, Argentina
| | - Nicolás R Figueroa
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario 2000, Argentina
| | - Claudia P Spampinato
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario 2000, Argentina.
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4
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Ramos RS, Spampinato CP. Deficiency of the Arabidopsis mismatch repair MSH6 attenuates Pseudomonas syringae invasion. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2023; 332:111713. [PMID: 37068662 DOI: 10.1016/j.plantsci.2023.111713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 04/12/2023] [Accepted: 04/14/2023] [Indexed: 05/27/2023]
Abstract
The MutS homolog 6 (MSH6) is a nuclear DNA mismatch repair (MMR) gene that encodes the MSH6 protein. MSH6 interacts with MSH2 to form the MutSα heterodimer. MutSα corrects DNA mismatches and unpaired nucleotides arising during DNA replication, deamination of 5-methylcytosine, and recombination between non-identical DNA sequences. In addition to correcting DNA biosynthetic errors, MutSα also recognizes chemically damaged DNA bases. Here, we show that inactivation of MSH6 affects the basal susceptibility of Arabidopsis thaliana to Pseudomonas syringae pv tomato DC3000. The msh6 T-DNA insertional mutant exhibited a reduced susceptibility to the bacterial invasion. This heightened basal resistance of msh6 mutants appears to be dependent on an increased stomatal closure, an accumulation of H2O2 and double-strand breaks (DSBs) and a constitutive expression of pathogenesis-related (NPR1 and PR1) and DNA damage response (RAD51D and SOG1) genes. Complementation of this mutant with the MSH6 wild type allele under the control of its own promoter resulted in reversal of the basal bacterial resistance phenotype and the stomatal closure back to wild type levels. Taken together, these results demonstrate that inactivation of MSH6 increases Arabidopsis basal susceptibility to the bacterial pathogen and suggests a link between DNA repair and stress signaling in plants.
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Affiliation(s)
- Rocío S Ramos
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000 Rosario, Argentina
| | - Claudia P Spampinato
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000 Rosario, Argentina.
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5
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Emmenecker C, Mézard C, Kumar R. Repair of DNA double-strand breaks in plant meiosis: role of eukaryotic RecA recombinases and their modulators. PLANT REPRODUCTION 2023; 36:17-41. [PMID: 35641832 DOI: 10.1007/s00497-022-00443-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 05/09/2022] [Indexed: 06/15/2023]
Abstract
Homologous recombination during meiosis is crucial for the DNA double-strand breaks (DSBs) repair that promotes the balanced segregation of homologous chromosomes and enhances genetic variation. In most eukaryotes, two recombinases RAD51 and DMC1 form nucleoprotein filaments on single-stranded DNA generated at DSB sites and play a central role in the meiotic DSB repair and genome stability. These nucleoprotein filaments perform homology search and DNA strand exchange to initiate repair using homologous template-directed sequences located elsewhere in the genome. Multiple factors can regulate the assembly, stability, and disassembly of RAD51 and DMC1 nucleoprotein filaments. In this review, we summarize the current understanding of the meiotic functions of RAD51 and DMC1 and the role of their positive and negative modulators. We discuss the current models and regulators of homology searches and strand exchange conserved during plant meiosis. Manipulation of these repair factors during plant meiosis also holds a great potential to accelerate plant breeding for crop improvements and productivity.
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Affiliation(s)
- Côme Emmenecker
- Institut Jean-Pierre Bourgin (IJPB), Université Paris-Saclay, INRAE, AgroParisTech, 78000, Versailles, France
- University of Paris-Sud, Université Paris-Saclay, 91405, Orsay, France
| | - Christine Mézard
- Institut Jean-Pierre Bourgin (IJPB), CNRS, Université Paris-Saclay, INRAE, AgroParisTech, 78000, Versailles, France.
| | - Rajeev Kumar
- Institut Jean-Pierre Bourgin (IJPB), Université Paris-Saclay, INRAE, AgroParisTech, 78000, Versailles, France.
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6
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Chirinos-Arias MC, Spampinato CP. Role of the mismatch repair protein MSH7 in Arabidopsis adaptation to acute salt stress. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2021; 169:280-290. [PMID: 34823145 DOI: 10.1016/j.plaphy.2021.11.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 11/11/2021] [Accepted: 11/16/2021] [Indexed: 06/13/2023]
Abstract
DNA mismatch repair (MMR) is a highly conserved pathway in evolution responsible for maintaining genomic stability. MMR is initiated when MutS proteins recognize and repair single base-base mismatches and small loops of unpaired nucleotides as well as certain types of DNA damage. Arabidopsis thaliana and other plants contain MutS protein homologs (MSH) found in other eukaryotic organisms and a unique MSH7 polypeptide. In this study, we first evaluated transient expression profiles of ten-days old pAtMSH7:GUS transgenic seedlings at different recovery times after an acute treatment for 48 hs with100 mM NaCl. GUS histochemical staining indicated that MSH7 expression is repressed by salt exposure but recovers progressively. Then, ten-days old mutants harboring two independent msh7 alleles were exposed for 48 hs with100 mM NaCl and different traits were measured over recovery time. Salt treated msh7 seedlings were defective in G2/M arrest. As a result, msh7 seedlings showed a reduced salt inhibitory effect as evidenced by a decreased reduction of rosette and leaf areas, stomatal density, total leaf number, silique length and seed number per silique. These findings suggest that disruption of MSH7 activity could be a promising approach for plant adaptive responses to salinity stress.
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Affiliation(s)
- Michelle C Chirinos-Arias
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000, Rosario, Argentina
| | - Claudia P Spampinato
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000, Rosario, Argentina.
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7
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Raina A, Sahu PK, Laskar RA, Rajora N, Sao R, Khan S, Ganai RA. Mechanisms of Genome Maintenance in Plants: Playing It Safe With Breaks and Bumps. Front Genet 2021; 12:675686. [PMID: 34239541 PMCID: PMC8258418 DOI: 10.3389/fgene.2021.675686] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 05/04/2021] [Indexed: 01/14/2023] Open
Abstract
Maintenance of genomic integrity is critical for the perpetuation of all forms of life including humans. Living organisms are constantly exposed to stress from internal metabolic processes and external environmental sources causing damage to the DNA, thereby promoting genomic instability. To counter the deleterious effects of genomic instability, organisms have evolved general and specific DNA damage repair (DDR) pathways that act either independently or mutually to repair the DNA damage. The mechanisms by which various DNA repair pathways are activated have been fairly investigated in model organisms including bacteria, fungi, and mammals; however, very little is known regarding how plants sense and repair DNA damage. Plants being sessile are innately exposed to a wide range of DNA-damaging agents both from biotic and abiotic sources such as ultraviolet rays or metabolic by-products. To escape their harmful effects, plants also harbor highly conserved DDR pathways that share several components with the DDR machinery of other organisms. Maintenance of genomic integrity is key for plant survival due to lack of reserve germline as the derivation of the new plant occurs from the meristem. Untowardly, the accumulation of mutations in the meristem will result in a wide range of genetic abnormalities in new plants affecting plant growth development and crop yield. In this review, we will discuss various DNA repair pathways in plants and describe how the deficiency of each repair pathway affects plant growth and development.
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Affiliation(s)
- Aamir Raina
- Mutation Breeding Laboratory, Department of Botany, Aligarh Muslim University, Aligarh, India
- Botany Section, Women’s College, Aligarh Muslim University, Aligarh, India
| | - Parmeshwar K. Sahu
- Department of Genetics and Plant Breeding, Indira Gandhi Agriculture University, Raipur, India
| | | | - Nitika Rajora
- National Agri-Food Biotechnology Institute, Mohali, India
| | - Richa Sao
- Department of Genetics and Plant Breeding, Indira Gandhi Agriculture University, Raipur, India
| | - Samiullah Khan
- Mutation Breeding Laboratory, Department of Botany, Aligarh Muslim University, Aligarh, India
| | - Rais A. Ganai
- Watson-Crick Centre for Molecular Medicine, Islamic University of Science and Technology, Awantipora, India
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Higgins EE, Howell EC, Armstrong SJ, Parkin IAP. A major quantitative trait locus on chromosome A9, BnaPh1, controls homoeologous recombination in Brassica napus. THE NEW PHYTOLOGIST 2021; 229:3281-3293. [PMID: 33020949 PMCID: PMC7984352 DOI: 10.1111/nph.16986] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 09/23/2020] [Indexed: 05/09/2023]
Abstract
Ensuring faithful homologous recombination in allopolyploids is essential to maintain optimal fertility of the species. Variation in the ability to control aberrant pairing between homoeologous chromosomes in Brassica napus has been identified. The current study exploited the extremes of such variation to identify genetic factors that differentiate newly resynthesised B. napus, which is inherently unstable, and established B. napus, which has adapted to largely control homoeologous recombination. A segregating B. napus mapping population was analysed utilising both cytogenetic observations and high-throughput genotyping to quantify the levels of homoeologous recombination. Three quantitative trait loci (QTL) were identified that contributed to the control of homoeologous recombination in the important oilseed crop B. napus. One major QTL on BnaA9 contributed between 32 and 58% of the observed variation. This study is the first to assess homoeologous recombination and map associated QTLs resulting from deviations in normal pairing in allotetraploid B. napus. The identified QTL regions suggest candidate meiotic genes that could be manipulated in order to control this important trait and further allow the development of molecular markers to utilise this trait to exploit homoeologous recombination in a crop.
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Affiliation(s)
- Erin E. Higgins
- Agriculture and Agri‐Food Canada107 Science PlaceSaskatoonSKS7N 0X2Canada
| | - Elaine C. Howell
- School of BiosciencesUniversity of BirminghamEdgbastonBirminghamB15 2TTUK
| | - Susan J. Armstrong
- School of BiosciencesUniversity of BirminghamEdgbastonBirminghamB15 2TTUK
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9
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Serra H, Svačina R, Baumann U, Whitford R, Sutton T, Bartoš J, Sourdille P. Ph2 encodes the mismatch repair protein MSH7-3D that inhibits wheat homoeologous recombination. Nat Commun 2021; 12:803. [PMID: 33547285 PMCID: PMC7865012 DOI: 10.1038/s41467-021-21127-1] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Accepted: 01/13/2021] [Indexed: 02/06/2023] Open
Abstract
Meiotic recombination is a critical process for plant breeding, as it creates novel allele combinations that can be exploited for crop improvement. In wheat, a complex allohexaploid that has a diploid-like behaviour, meiotic recombination between homoeologous or alien chromosomes is suppressed through the action of several loci. Here, we report positional cloning of Pairing homoeologous 2 (Ph2) and functional validation of the wheat DNA mismatch repair protein MSH7-3D as a key inhibitor of homoeologous recombination, thus solving a half-century-old question. Similar to ph2 mutant phenotype, we show that mutating MSH7-3D induces a substantial increase in homoeologous recombination (up to 5.5 fold) in wheat-wild relative hybrids, which is also associated with a reduction in homologous recombination. These data reveal a role for MSH7-3D in meiotic stabilisation of allopolyploidy and provides an opportunity to improve wheat's genetic diversity through alien gene introgression, a major bottleneck facing crop improvement.
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Affiliation(s)
- Heïdi Serra
- Genetics, Diversity and Ecophysiology of Cereals, UMR 1095, INRAE, Université Clermont Auvergne, Clermont-Ferrand, France. .,Genetics, Reproduction and Development, CNRS, Inserm, Université Clermont Auvergne, Clermont-Ferrand, France.
| | - Radim Svačina
- Institute of Experimental Botany of the Czech Academy of Sciences, Centre of the Region Hana for Biotechnological and Agricultural Research, Olomouc, Czech Republic
| | - Ute Baumann
- School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, PMB1, Glen Osmond, SA, Australia
| | - Ryan Whitford
- School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, PMB1, Glen Osmond, SA, Australia
| | - Tim Sutton
- School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, PMB1, Glen Osmond, SA, Australia.,South Australian Research and Development Institute, Adelaide, SA, Australia
| | - Jan Bartoš
- Institute of Experimental Botany of the Czech Academy of Sciences, Centre of the Region Hana for Biotechnological and Agricultural Research, Olomouc, Czech Republic
| | - Pierre Sourdille
- Genetics, Diversity and Ecophysiology of Cereals, UMR 1095, INRAE, Université Clermont Auvergne, Clermont-Ferrand, France.
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10
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The Dark Side of UV-Induced DNA Lesion Repair. Genes (Basel) 2020; 11:genes11121450. [PMID: 33276692 PMCID: PMC7761550 DOI: 10.3390/genes11121450] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 11/27/2020] [Accepted: 11/29/2020] [Indexed: 12/12/2022] Open
Abstract
In their life cycle, plants are exposed to various unfavorable environmental factors including ultraviolet (UV) radiation emitted by the Sun. UV-A and UV-B, which are partially absorbed by the ozone layer, reach the surface of the Earth causing harmful effects among the others on plant genetic material. The energy of UV light is sufficient to induce mutations in DNA. Some examples of DNA damage induced by UV are pyrimidine dimers, oxidized nucleotides as well as single and double-strand breaks. When exposed to light, plants can repair major UV-induced DNA lesions, i.e., pyrimidine dimers using photoreactivation. However, this highly efficient light-dependent DNA repair system is ineffective in dim light or at night. Moreover, it is helpless when it comes to the repair of DNA lesions other than pyrimidine dimers. In this review, we have focused on how plants cope with deleterious DNA damage that cannot be repaired by photoreactivation. The current understanding of light-independent mechanisms, classified as dark DNA repair, indispensable for the maintenance of plant genetic material integrity has been presented.
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11
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Gonzalez V, Spampinato CP. The mismatch repair protein MSH6 regulates somatic recombination in Arabidopsis thaliana. DNA Repair (Amst) 2020; 87:102789. [PMID: 31945543 DOI: 10.1016/j.dnarep.2020.102789] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 11/29/2019] [Accepted: 01/08/2020] [Indexed: 11/28/2022]
Abstract
The mismatch repair (MMR) pathway promotes genome stability by controlling the fidelity of replication and recombination. The first step of the pathway involves recognition of the mismatch by heterodimers composed of MutS homologs (MSH). Although MSH6 has been well characterized in yeasts and humans, the role of the plant protein has not been extensively studied. We first analyzed gene expression in Arabidopsis thaliana. The use of transgenic plants expressing the β-glucuronidase (GUS) reporter gene under the control of approximately 1-kb region upstream of the start codon of the AtMSH6 gene demonstrated that MSH6 is preferentially expressed in undifferentiated cells with an intense cell division rate. We then examined protein function in meiotic and somatic recombination. Suppression of AtMSH6 did not affect the rate of meiotic recombination, but increased the frequency of recombination between two homeologous repeats of a marker gene by 3-fold relative to wild-type plants. Expression of the AtMSH6 gene under the control of its own promoter in msh6 homozygous mutant plants rescued the altered somatic recombination phenotype. We conclude that MSH6 shows a functional conservation across different biological kingdoms and a functional specificity in plants.
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Affiliation(s)
- Valentina Gonzalez
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000, Rosario, Argentina
| | - Claudia P Spampinato
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000, Rosario, Argentina.
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12
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Chirinos-Arias MC, Spampinato CP. Growth and development of AtMSH7 mutants in Arabidopsis thaliana. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2020; 146:329-336. [PMID: 31785519 DOI: 10.1016/j.plaphy.2019.11.035] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 11/18/2019] [Accepted: 11/22/2019] [Indexed: 06/10/2023]
Abstract
DNA mismatch repair (MMR) is a highly conserved biological pathway that improves the fidelity of DNA replication and recombination. MMR is initiated when MutS proteins recognize mismatches and small loops of unpaired nucleotides. Arabidopsis thaliana and other plants encode MutS protein homologs (MSH) conserved among other eukaryotic organisms, but also encode an extra MSH polypeptide (MSH7). In order to better understand the role of MSH7 in vivo, a full set of phenotypic parameters that covered the development of the plant from seed imbibition to flowering and seed maturation was analyzed in A. thaliana harboring two different msh7 alleles. Plants deficient in MSH7 show statistically significant faster germination rates, longer primary roots during the juvenile vegetative phase, and higher cauline leaf and axillary and lateral inflorescence numbers compared with wild type. We also quantified number, length and area of siliques and seed number per silique. Disruption of MSH7 resulted in a higher number of smaller siliques than wild type. There were no differences in seed number per silique between genotypes. These findings suggest that mutant plant growth appears to be caused by an impaired cell cycle checkpoint that allows cell division without adequate DNA repair. This increase in proliferation activity demonstrates a functional and temporal link between DNA repair and cell cycle regulation.
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Affiliation(s)
- Michelle C Chirinos-Arias
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000, Rosario, Argentina
| | - Claudia P Spampinato
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000, Rosario, Argentina.
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13
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Llabata P, Richter J, Faus I, Słomiňska-Durdasiak K, Zeh LH, Gadea J, Hauser MT. Involvement of the eIF2α Kinase GCN2 in UV-B Responses. FRONTIERS IN PLANT SCIENCE 2019; 10:1492. [PMID: 31850012 PMCID: PMC6892979 DOI: 10.3389/fpls.2019.01492] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 10/28/2019] [Indexed: 05/12/2023]
Abstract
GCN2 (general control nonrepressed 2) is a serine/threonine-protein kinase that regulates translation in response to stressors such as amino acid and purin deprivation, cold shock, wounding, cadmium, and UV-C exposure. Activated GCN2 phosphorylates the α-subunit of the eukaryotic initiation factor 2 (eIF2) leading to a drastic inhibition of protein synthesis and shifting translation to specific mRNAs. To investigate the role of GCN2 in responses to UV-B radiation its activity was analyzed through eIF2α phosphorylation assays in mutants of the specific UV-B and stress signaling pathways of Arabidopsis thaliana. EIF2α phosphorylation was detectable 30 min after UV-B exposure, independent of the UV-B photoreceptor UV RESISTANCE LOCUS8 and its downstream signaling components. GCN2 dependent phosphorylation of eIF2α was also detectable in mutants of the stress related MAP kinases, MPK3 and MPK6 and their negative regulator map kinase phosphatase1 (MKP1). Transcription of downstream components of the UV-B signaling pathway, the Chalcone synthase (CHS) was constitutively higher in gcn2-1 compared to wildtype and further increased upon UV-B while GLUTATHIONE PEROXIDASE7 (GPX7) behaved similarly to wildtype. The UVR8 independent FAD-LINKED OXIDOREDUCTASE (FADox) had a lower basal expression in gcn2-1 which was increased upon UV-B. Since high fluence rates of UV-B induce DNA damage the expression of the RAS ASSOCIATED WITH DIABETES PROTEIN51 (RAD51) was quantified before and after UV-B. While the basal expression was similar to wildtype it was significantly less induced upon UV-B in the gcn2-1 mutant. This expression pattern correlates with the finding that gcn2 mutants develop less cyclobutane pyrimidine dimers after UV-B exposure. Quantification of translation with the puromycination assay revealed that gcn2 mutants have an increased rate of translation which was also higher upon UV-B. Growth of gcn2 mutants to chronic UV-B exposure supports GCN2's role as a negative regulator of UV-B responses. The elevated resistance of gcn2 mutants towards repeated UV-B exposure points to a critical role of GCN2 in the regulation of translation upon UV-B.
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Affiliation(s)
- Paula Llabata
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Universidad Politécnica de Valencia (UPV), Consejo Superior de Investigaciones Científicas (CSIC), Ciudad Politécnica de la Innovación (CPI), Valencia, Spain
- Institute of Applied Genetics and Cell Biology, BOKU University of Natural Resources and Life Sciences, Vienna, Austria
- Bellvitge Biomedical Research Institute IDIBELL, Barcelona, Spain
| | - Julia Richter
- Institute of Applied Genetics and Cell Biology, BOKU University of Natural Resources and Life Sciences, Vienna, Austria
| | - Isabel Faus
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Universidad Politécnica de Valencia (UPV), Consejo Superior de Investigaciones Científicas (CSIC), Ciudad Politécnica de la Innovación (CPI), Valencia, Spain
| | - Karolina Słomiňska-Durdasiak
- Institute of Applied Genetics and Cell Biology, BOKU University of Natural Resources and Life Sciences, Vienna, Austria
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, Germany
| | - Lukas Hubert Zeh
- Institute of Applied Genetics and Cell Biology, BOKU University of Natural Resources and Life Sciences, Vienna, Austria
| | - Jose Gadea
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Universidad Politécnica de Valencia (UPV), Consejo Superior de Investigaciones Científicas (CSIC), Ciudad Politécnica de la Innovación (CPI), Valencia, Spain
| | - Marie-Theres Hauser
- Institute of Applied Genetics and Cell Biology, BOKU University of Natural Resources and Life Sciences, Vienna, Austria
- *Correspondence: Marie-Theres Hauser,
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Roy Chowdhury M, Basak J. Tiny Yet Indispensable Plant MicroRNAs Are Worth to Explore as Key Components for Combating Genotoxic Stresses. FRONTIERS IN PLANT SCIENCE 2019; 10:1197. [PMID: 31636646 PMCID: PMC6788304 DOI: 10.3389/fpls.2019.01197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Accepted: 08/30/2019] [Indexed: 05/03/2023]
Abstract
Plants being sessile are always exposed to various stresses including biotic and abiotic stresses. Some of these stresses are genotoxic to cells causing DNA damage by forming lesions which include altered bases, cross-links, and breaking of DNA strands, which in turn hamper the genomic integrity. In order to survive through all these adverse conditions, plants have evolved different DNA repair mechanisms. As seen from the mammalian system and different human diseases, various microRNAs (miRNAs) can target the 3'-untranslated region of mRNAs that code for the proteins involved in DNA repair pathways. Since miRNAs play an important role in plant cells by regulating various metabolic pathways, it can also be possible that miRNAs play an important role in DNA repair pathways too. However, till date, only a handful of plant miRNAs have been identified to play important role in combating genotoxic stresses in plants. Limitation of information regarding involvement of miRNAs in DNA repair as well as in ROS scavenging prompted us to gather information about plant miRNAs specific for these tasks. This mini-review aims to present pertinent literature dealing with different genotoxic stresses that cause genome instability as well as plant specific responses to survive the damage. This is intertwined with the involvement of miRNAs in genotoxic stress in plants, challenges of applying miRNAs as a tool to combat DNA damage along with ways to overcome these challenges, and finally, the future prospective of these understudied aspects.
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Affiliation(s)
- Moumita Roy Chowdhury
- Computational Structural Biology Lab, Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, India
| | - Jolly Basak
- Laboratory of Plant Stress Biology, Department of Biotechnology, Visva-Bharati, University Santiniketan, India
- *Correspondence: Jolly Basak,
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van Tol N, Rolloos M, van Loon P, van der Zaal BJ. MeioSeed: a CellProfiler-based program to count fluorescent seeds for crossover frequency analysis in Arabidopsis thaliana. PLANT METHODS 2018; 14:32. [PMID: 29692862 PMCID: PMC5905130 DOI: 10.1186/s13007-018-0298-3] [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: 12/08/2017] [Accepted: 04/07/2018] [Indexed: 05/02/2023]
Abstract
BACKGROUND The formation of crossovers during meiosis is pivotal for the redistribution of traits among the progeny of sexually reproducing organisms. In plants the molecular mechanisms underlying the formation of crossovers have been well established, but relatively little is known about the factors that determine the exact location and the frequency of crossover events in the genome. In the model plant species Arabidopsis, research on these factors has been greatly facilitated by reporter lines containing linked fluorescence marker genes under control of promoters active in seeds or pollen, allowing for the visualization of crossover events by fluorescence microscopy. However, the usefulness of these reporter lines to screen for novel modulators of crossover frequency in a high throughput manner relies on the availability of programs that can accurately count fluorescent seeds. Such a program was previously not available in scientific literature. RESULTS Here we present MeioSeed, a novel CellProfiler-based program that accurately counts GFP and RFP fluorescent Arabidopsis seeds with adjustable detection thresholds for fluorescence intensity, making use of a robust seed classifier which was trained by machine learning in Ilastik. Using the previously published reporter line Col3-4/20 as an example, we explain the use of MeioSeed and the steps taken to optimize the thresholding settings of the program to fit the published model for recombination frequency and transgene segregation. The use of MeioSeed is illustrated by investigating salt stress as a novel abiotic trigger for changes in crossover frequency in Col3-4/20 (♂) × Ler-0 (♀) F1 hybrids. Salt stress was found to trigger increases in crossover frequency between the marker genes of up to 70% compared to the control treatment without salt stress. Genotyping of control and salt treated populations revealed that the changes in crossover frequency were not limited to the region between the marker genes, but that fluctuations in crossover frequency are likely to occur genome-wide after treatment with high salt concentrations. CONCLUSIONS MeioSeed allows for the high throughput recognition and counting of fluorescent Arabidopsis seeds and can facilitate the screening for novel abiotic and biotic modulators of crossover frequency using reporter lines in Arabidopsis.
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Affiliation(s)
- Niels van Tol
- Faculty of Science, Institute of Biology Leiden, Leiden University, Sylviusweg 72, 2333 BE Leiden, The Netherlands
| | - Martijn Rolloos
- Faculty of Science, Institute of Biology Leiden, Leiden University, Sylviusweg 72, 2333 BE Leiden, The Netherlands
| | - Peter van Loon
- Rijk Zwaan Breeding BV, Eerste Kruisweg, 4793 RS Fijnaart, The Netherlands
| | - Bert J. van der Zaal
- Faculty of Science, Institute of Biology Leiden, Leiden University, Sylviusweg 72, 2333 BE Leiden, The Netherlands
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Sarma S, Pandey AK, Sharma K, Ravi M, Sreelakshmi Y, Sharma R. MutS-Homolog2 silencing generates tetraploid meiocytes in tomato ( Solanum lycopersicum). PLANT DIRECT 2018; 2:e00017. [PMID: 31245679 PMCID: PMC6508528 DOI: 10.1002/pld3.17] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2017] [Revised: 09/07/2017] [Accepted: 09/12/2017] [Indexed: 05/16/2023]
Abstract
MSH2 is the core protein of MutS-homolog family involved in recognition and repair of the errors in the DNA. While other members of MutS-homolog family reportedly regulate mitochondrial stability, meiosis, and fertility, MSH2 is believed to participate mainly in mismatch repair. The search for polymorphism in MSH2 sequence in tomato accessions revealed both synonymous and nonsynonymous SNPs; however, SIFT algorithm predicted that none of the SNPs influenced MSH2 protein function. The silencing of MSH2 gene expression by RNAi led to phenotypic abnormalities in highly silenced lines, particularly in the stamens with highly reduced pollen formation. MSH2 silencing exacerbated formation of UV-B-induced thymine dimers and blocked light-induced repair of the dimers. The MSH2 silencing also affected the progression of male meiosis to a varying degree with either halt of meiosis at zygotene stage or formation of diploid tetrads. The immunostaining of male meiocytes with centromere localized CENPC (centromere protein C) antibody showed the presence of 48 univalent along with 24 bivalent chromosomes suggesting abnormal tetraploid meiosis. The mitotic cells of root tips of silenced lines showed diploid nuclei but lacked intervening cell plates leading to cells with syncytial nuclei. Thus, we speculate that tetraploid pollen mother cells may have arisen due to the fusion of syncytial nuclei before the onset of meiosis. It is likely that in addition to mismatch repair (MMR), MSH2 may have an additional role in regulating ploidy stability.
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Affiliation(s)
- Supriya Sarma
- Repository of Tomato Genomics ResourcesDepartment of Plant SciencesSchool of Life SciencesUniversity of HyderabadHyderabadIndia
- Present address:
Centre for Cellular and Molecular BiologyHyderabadIndia
| | - Arun Kumar Pandey
- Repository of Tomato Genomics ResourcesDepartment of Plant SciencesSchool of Life SciencesUniversity of HyderabadHyderabadIndia
- Present address:
International Crops Research Institute for the Semi‐Arid Tropics (ICRISAT)HyderabadIndia
| | - Kapil Sharma
- Repository of Tomato Genomics ResourcesDepartment of Plant SciencesSchool of Life SciencesUniversity of HyderabadHyderabadIndia
| | - Maruthachalam Ravi
- School of BiologyIndian Institute of Science Education and ResearchThiruvananthapuramKeralaIndia
| | - Yellamaraju Sreelakshmi
- Repository of Tomato Genomics ResourcesDepartment of Plant SciencesSchool of Life SciencesUniversity of HyderabadHyderabadIndia
| | - Rameshwar Sharma
- Repository of Tomato Genomics ResourcesDepartment of Plant SciencesSchool of Life SciencesUniversity of HyderabadHyderabadIndia
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Spampinato CP. Protecting DNA from errors and damage: an overview of DNA repair mechanisms in plants compared to mammals. Cell Mol Life Sci 2017; 74:1693-1709. [PMID: 27999897 PMCID: PMC11107726 DOI: 10.1007/s00018-016-2436-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Revised: 12/01/2016] [Accepted: 12/05/2016] [Indexed: 01/10/2023]
Abstract
The genome integrity of all organisms is constantly threatened by replication errors and DNA damage arising from endogenous and exogenous sources. Such base pair anomalies must be accurately repaired to prevent mutagenesis and/or lethality. Thus, it is not surprising that cells have evolved multiple and partially overlapping DNA repair pathways to correct specific types of DNA errors and lesions. Great progress in unraveling these repair mechanisms at the molecular level has been made by several talented researchers, among them Tomas Lindahl, Aziz Sancar, and Paul Modrich, all three Nobel laureates in Chemistry for 2015. Much of this knowledge comes from studies performed in bacteria, yeast, and mammals and has impacted research in plant systems. Two plant features should be mentioned. Plants differ from higher eukaryotes in that they lack a reserve germline and cannot avoid environmental stresses. Therefore, plants have evolved different strategies to sustain genome fidelity through generations and continuous exposure to genotoxic stresses. These strategies include the presence of unique or multiple paralogous genes with partially overlapping DNA repair activities. Yet, in spite (or because) of these differences, plants, especially Arabidopsis thaliana, can be used as a model organism for functional studies. Some advantages of this model system are worth mentioning: short life cycle, availability of both homozygous and heterozygous lines for many genes, plant transformation techniques, tissue culture methods and reporter systems for gene expression and function studies. Here, I provide a current understanding of DNA repair genes in plants, with a special focus on A. thaliana. It is expected that this review will be a valuable resource for future functional studies in the DNA repair field, both in plants and animals.
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Affiliation(s)
- Claudia P Spampinato
- Facultad de Ciencias Bioquímicas y Farmacéuticas, Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Universidad Nacional de Rosario, Suipacha 531, 2000, Rosario, Argentina.
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18
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Fina JP, Masotti F, Rius SP, Crevacuore F, Casati P. HAC1 and HAF1 Histone Acetyltransferases Have Different Roles in UV-B Responses in Arabidopsis. FRONTIERS IN PLANT SCIENCE 2017; 8:1179. [PMID: 28740501 PMCID: PMC5502275 DOI: 10.3389/fpls.2017.01179] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 06/20/2017] [Indexed: 05/17/2023]
Abstract
Arabidopsis has 12 histone acetyltransferases grouped in four families: the GNAT/HAG, the MYST/HAM, the p300/CBP/HAC and the TAFII250/HAF families. We previously showed that ham1 and ham2 mutants accumulated higher damaged DNA after UV-B exposure than WT plants. In contrast, hag3 RNA interference transgenic plants showed less DNA damage and lower inhibition of plant growth by UV-B, and increased levels of UV-B-absorbing compounds. These results demonstrated that HAM1, HAM2, and HAG3 participate in UV-B-induced DNA damage repair and signaling. In this work, to further explore the role of histone acetylation in UV-B responses, a putative function of other acetyltransferases of the HAC and the HAF families was analyzed. Neither HAC nor HAF acetyltrasferases participate in DNA damage and repair after UV-B radiation in Arabidopsis. Despite this, haf1 mutants presented lower inhibition of leaf and root growth by UV-B, with altered expression of E2F transcription factors. On the other hand, hac1 plants showed a delay in flowering time after UV-B exposure and changes in FLC and SOC1 expression patterns. Our data indicate that HAC1 and HAF1 have crucial roles for in UV-B signaling, confirming that, directly or indirectly, both enzymes also have a role in UV-B responses.
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Pelin A, Moteshareie H, Sak B, Selman M, Naor A, Eyahpaise MÈ, Farinelli L, Golshani A, Kvac M, Corradi N. The genome of an Encephalitozoon cuniculi type III strain reveals insights into the genetic diversity and mode of reproduction of a ubiquitous vertebrate pathogen. Heredity (Edinb) 2016; 116:458-65. [PMID: 26837273 DOI: 10.1038/hdy.2016.4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Revised: 12/10/2015] [Accepted: 12/18/2015] [Indexed: 02/07/2023] Open
Abstract
Encephalitozoon cuniculi is a model microsporidian species with a mononucleate nucleus and a genome that has been extensively studied. To date, analyses of genome diversity have revealed the existence of four genotypes in E. cuniculi (EcI, II, III and IV). Genome sequences are available for EcI, II and III, and are all very divergent, possibly diploid and genetically homogeneous. The mechanisms that cause low genetic diversity in E. cuniculi (for example, selfing, inbreeding or a combination of both), as well as the degree of genetic variation in their natural populations, have been hard to assess because genome data have been so far gathered from laboratory-propagated strains. In this study, we aim to tackle this issue by analyzing the complete genome sequence of a natural strain of E. cuniculi isolated in 2013 from a steppe lemming. The strain belongs to the EcIII genotype and has been designated EcIII-L. The EcIII-L genome sequence harbors genomic features intermediate to known genomes of II and III lab strains, and we provide primers that differentiate the three E. cuniculi genotypes using a single PCR. Surprisingly, the EcIII-L genome is also highly homogeneous, harbors signatures of heterozygosity and also one strain-specific single-nucleotide polymorphism (SNP) that introduces a stop codon in a key meiosis gene, Spo11. Functional analyses using a heterologous system demonstrate that this SNP leads to a deficient meiosis in a model fungus. This indicates that EcIII-L meiotic machinery may be presently broken. Overall, our findings reveal previously unsuspected genome diversity in E. cuniculi, some of which appears to affect genes of primary importance for the biology of this pathogen.
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Affiliation(s)
- A Pelin
- Department of Biology, Canadian Institute for Advanced Research, University of Ottawa, Ottawa, ON, Canada
| | - H Moteshareie
- Department of Biology, Carleton University, Ottawa, Ontario, Canada.,Ottawa Institute of Systems Biology, Carleton University, Ottawa, Ontario, Canada
| | - B Sak
- Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic, České Budějovice, Czech Republic
| | - M Selman
- Department of Biology, Canadian Institute for Advanced Research, University of Ottawa, Ottawa, ON, Canada
| | - A Naor
- Department of Biology, Canadian Institute for Advanced Research, University of Ottawa, Ottawa, ON, Canada
| | - M-È Eyahpaise
- Department of Biology, Canadian Institute for Advanced Research, University of Ottawa, Ottawa, ON, Canada
| | - L Farinelli
- FASTERIS S.A., Ch. du Pont-du-Centenaire 109, Plan-les-Ouates, Switzerland
| | - A Golshani
- Department of Biology, Carleton University, Ottawa, Ontario, Canada.,Ottawa Institute of Systems Biology, Carleton University, Ottawa, Ontario, Canada
| | - M Kvac
- Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic, České Budějovice, Czech Republic
| | - N Corradi
- Department of Biology, Canadian Institute for Advanced Research, University of Ottawa, Ottawa, ON, Canada
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20
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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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