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Karafiátová M, Bojdová T, Stejskalová M, Harnádková N, Kumar V, Houben A, Chen J, Doležalová A, Honys D, Bartoš J. Unravelling the unusual: chromosome elimination, nondisjunction and extra pollen mitosis characterize the B chromosome in wild sorghum. THE NEW PHYTOLOGIST 2024. [PMID: 39010685 DOI: 10.1111/nph.19954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Accepted: 06/17/2024] [Indexed: 07/17/2024]
Abstract
The B chromosomes exhibit diverse behaviour compared with conventional genetic models. The capacity of the B chromosome either to accumulate or to be eliminated in a tissue-specific manner is dependent on biological processes related to aberrant cell division(s), but here yet remains compatible with normal development. We studied B chromosome elimination in Sorghum purpureosericeum embryos through cryo-sections and demonstrated the B chromosome instability during plant growth using flow cytometry, molecular markers and fluorescent in situ hybridization techniques. Consequently, using B chromosome-specific probes we revealed the non-Mendelian inheritance of B chromosomes in developing pollen. We disclosed that the occurrence of the B chromosome is specific to certain tissues or organs. The distribution pattern is mainly caused by an extensive elimination that functions primarily during embryo development and persists throughout plant development. Furthermore, we described that B chromosome accumulation can occur either by nondisjunction at first pollen mitosis (PMI) or the initiation of extra nuclear division(s) during pollen development. Our study demonstrates the existence of a not-yet-fully described B chromosome drive process, which is likely under the control of the B chromosome.
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Affiliation(s)
- Miroslava Karafiátová
- Institute of Experimental Botany of the Czech Academy of Sciences, Centre of Plant Structural and Functional Genomics, Šlechtitelů 31, 779 00, Olomouc, Czech Republic
| | - Tereza Bojdová
- Institute of Experimental Botany of the Czech Academy of Sciences, Centre of Plant Structural and Functional Genomics, Šlechtitelů 31, 779 00, Olomouc, Czech Republic
- Department of Cell Biology and Genetics, Faculty of Science, Palacky University, Šlechtitelů 27, 779 00, Olomouc, Czech Republic
| | - Magdaléna Stejskalová
- Institute of Experimental Botany of the Czech Academy of Sciences, Centre of Plant Structural and Functional Genomics, Šlechtitelů 31, 779 00, Olomouc, Czech Republic
| | - Natália Harnádková
- Institute of Experimental Botany of the Czech Academy of Sciences, Centre of Plant Structural and Functional Genomics, Šlechtitelů 31, 779 00, Olomouc, Czech Republic
| | - Vinod Kumar
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02, Prague 6 - Lysolaje, Czech Republic
| | - Andreas Houben
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), 06466, Seeland OT Gatersleben, Germany
| | - Jianyong Chen
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), 06466, Seeland OT Gatersleben, Germany
| | - Alžběta Doležalová
- Institute of Experimental Botany of the Czech Academy of Sciences, Centre of Plant Structural and Functional Genomics, Šlechtitelů 31, 779 00, Olomouc, Czech Republic
| | - David Honys
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, Rozvojová 263, 165 02, Prague 6 - Lysolaje, Czech Republic
| | - Jan Bartoš
- Institute of Experimental Botany of the Czech Academy of Sciences, Centre of Plant Structural and Functional Genomics, Šlechtitelů 31, 779 00, Olomouc, Czech Republic
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2
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Zumkeller C, Schindler D, Felder J, Waldminghaus T. Modular Assembly of Synthetic Secondary Chromosomes. Methods Mol Biol 2024; 2819:157-187. [PMID: 39028507 DOI: 10.1007/978-1-0716-3930-6_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2024]
Abstract
The development of novel DNA assembly methods in recent years has paved the way for the construction of synthetic replicons to be used for basic research and biotechnological applications. A learning-by-building approach can now answer questions about how chromosomes must be constructed to maintain genetic information. Here we describe an efficient pipeline for the design and assembly of synthetic, secondary chromosomes in Escherichia coli based on the popular modular cloning (MoClo) system.
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Affiliation(s)
- Celine Zumkeller
- Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Branch for Bioresources, Giessen, Germany
| | - Daniel Schindler
- Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
- Center for Synthetic Microbiology (SYNMIKRO), Marburg, Germany
| | - Jennifer Felder
- Technische Universität Darmstadt, Faculty of Biology, Darmstadt, Germany
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3
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Jiao Y, Wang Y. Towards Plant Synthetic Genomics. BIODESIGN RESEARCH 2023; 5:0020. [PMID: 37849467 PMCID: PMC10578142 DOI: 10.34133/bdr.0020] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 10/04/2023] [Indexed: 10/19/2023] Open
Abstract
Rapid advances in DNA synthesis techniques have allowed the assembly and engineering of viral and microbial genomes. Multicellular eukaryotic organisms, with their larger genomes, abundant transposons, and prevalent epigenetic regulation, present a new frontier to synthetic genomics. Plant synthetic genomics have long been proposed, and exciting progress has been made using the top-down approach. In this perspective, we propose applying bottom-up genome synthesis in multicellular plants, starting from the model moss Physcomitrium patens, in which homologous recombination, DNA delivery, and regeneration are possible, although further optimizations are necessary. We then discuss technical barriers, including genome assembly and plant transformation, associated with synthetic genomics in seed plants.
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Affiliation(s)
- Yuling Jiao
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences,
Peking University, Beijing 100871, China
- Peking-Tsinghua Center for Life Sciences, Center for Quantitative Biology, Academy for Advanced Interdisciplinary Studies,
Peking University, Beijing 100871, China
- Peking University Institute of Advanced Agricultural Sciences, Shandong Laboratory of Advanced Agricultural Sciences in Weifang, Weifang, Shandong 261325, China
| | - Ying Wang
- College of Life Sciences,
University of Chinese Academy of Sciences, Beijing 100049, China
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4
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Xu C, Birchler JA. Editorial: Plant artificial chromosomes: progress and perspectives. FRONTIERS IN PLANT SCIENCE 2023; 14:1290386. [PMID: 37822343 PMCID: PMC10562729 DOI: 10.3389/fpls.2023.1290386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 09/14/2023] [Indexed: 10/13/2023]
Affiliation(s)
- Chunhui Xu
- Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao, China
| | - James A. Birchler
- Division of Biological Sciences, University of Missouri at Columbia, Columbia, MO, United States
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5
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Gomide MDS, Leitão MDC, Coelho CM. Biocircuits in plants and eukaryotic algae. FRONTIERS IN PLANT SCIENCE 2022; 13:982959. [PMID: 36212277 PMCID: PMC9545776 DOI: 10.3389/fpls.2022.982959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 08/22/2022] [Indexed: 06/16/2023]
Abstract
As one of synthetic biology's foundations, biocircuits are a strategy of genetic parts assembling to recognize a signal and to produce a desirable output to interfere with a biological function. In this review, we revisited the progress in the biocircuits technology basis and its mandatory elements, such as the characterization and assembly of functional parts. Furthermore, for a successful implementation, the transcriptional control systems are a relevant point, and the computational tools help to predict the best combinations among the biological parts planned to be used to achieve the desirable phenotype. However, many challenges are involved in delivering and stabilizing the synthetic structures. Some research experiences, such as the golden crops, biosensors, and artificial photosynthetic structures, can indicate the positive and limiting aspects of the practice. Finally, we envision that the modulatory structural feature and the possibility of finer gene regulation through biocircuits can contribute to the complex design of synthetic chromosomes aiming to develop plants and algae with new or improved functions.
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Affiliation(s)
- Mayna da Silveira Gomide
- Laboratory of Synthetic Biology, Department of Genetics and Morphology, Institute of Biological Science, University of Brasília (UnB), Brasília, Distrito Federal, Brazil
- School of Medicine, Federal University of Juiz de Fora (UFJF), Juiz de Fora, Minas Gerais, Brazil
| | - Matheus de Castro Leitão
- Laboratory of Synthetic Biology, Department of Genetics and Morphology, Institute of Biological Science, University of Brasília (UnB), Brasília, Distrito Federal, Brazil
| | - Cíntia Marques Coelho
- Laboratory of Synthetic Biology, Department of Genetics and Morphology, Institute of Biological Science, University of Brasília (UnB), Brasília, Distrito Federal, Brazil
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6
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Abstract
The supernumerary B chromosome of maize is dispensable, containing no vital genes, and thus is variable in number and presence in lines of maize. In order to be maintained in populations, it has a drive mechanism consisting of nondisjunction at the pollen mitosis that produces the two sperm cells, and then the sperm with the two B chromosomes has a preference for fertilizing the egg as opposed to the central cell in the process of double fertilization. The sequence of the B chromosome coupled with B chromosomal aberrations has localized features involved with nondisjunction and preferential fertilization, which are present at the centromeric region. The predicted genes from the sequence have paralogues dispersed across all A chromosomes and have widely different divergence times suggesting that they have transposed to the B chromosome over evolutionary time followed by degradation or have been co-opted for the selfish functions of the supernumerary chromosome.
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Affiliation(s)
- James A. Birchler
- Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Hua Yang
- Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA
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7
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Flavell RB. Perspective: 50 years of plant chromosome biology. PLANT PHYSIOLOGY 2021; 185:731-753. [PMID: 33604616 PMCID: PMC8133586 DOI: 10.1093/plphys/kiaa108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 12/04/2020] [Indexed: 06/12/2023]
Abstract
The past 50 years has been the greatest era of plant science discovery, and most of the discoveries have emerged from or been facilitated by our knowledge of plant chromosomes. At last we have descriptive and mechanistic outlines of the information in chromosomes that programs plant life. We had almost no such information 50 years ago when few had isolated DNA from any plant species. The important features of genes have been revealed through whole genome comparative genomics and testing of variants using transgenesis. Progress has been enabled by the development of technologies that had to be invented and then become widely available. Arabidopsis (Arabidopsis thaliana) and rice (Oryza sativa) have played extraordinary roles as model species. Unexpected evolutionary dramas were uncovered when learning that chromosomes have to manage constantly the vast numbers of potentially mutagenic families of transposons and other repeated sequences. The chromatin-based transcriptional and epigenetic mechanisms that co-evolved to manage the evolutionary drama as well as gene expression and 3-D nuclear architecture have been elucidated these past 20 years. This perspective traces some of the major developments with which I have become particularly familiar while seeking ways to improve crop plants. I draw some conclusions from this look-back over 50 years during which the scientific community has (i) exposed how chromosomes guard, readout, control, recombine, and transmit information that programs plant species, large and small, weed and crop, and (ii) modified the information in chromosomes for the purposes of genetic, physiological, and developmental analyses and plant improvement.
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Affiliation(s)
- Richard B Flavell
- International Wheat Yield Partnership, 1500 Research Parkway, College Station, TX 77843, USA
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8
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Dawe RK. Charting the path to fully synthetic plant chromosomes. Exp Cell Res 2020; 390:111951. [PMID: 32151492 DOI: 10.1016/j.yexcr.2020.111951] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 03/03/2020] [Accepted: 03/05/2020] [Indexed: 02/06/2023]
Abstract
The concepts of synthetic biology have the potential to transform plant genetics, both in how we analyze genetic pathways and how we transfer that knowledge into useful applications. While synthetic biology can be applied at the level of the single gene or small groups of genes, this commentary focuses on the ultimate challenge of designing fully synthetic plant chromosomes. Engineering at this scale will allow us to manipulate whole genome architecture and to modify multiple pathways and traits simultaneously. Advances in genome synthesis make it likely that the initial phases of plant chromosome construction will occur in bacteria and yeast. Here I discuss the next steps, including specific ways of overcoming technical barriers associated with plant transformation, functional centromere design, and ensuring accurate meiotic transmission.
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Affiliation(s)
- R Kelly Dawe
- Department of Genetics and Department of Plant Biology, University of Georgia, Athens, GA, 30602, USA.
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9
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Rycroft T, Hamilton K, Haas CN, Linkov I. A quantitative risk assessment method for synthetic biology products in the environment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 696:133940. [PMID: 31446290 DOI: 10.1016/j.scitotenv.2019.133940] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 08/13/2019] [Accepted: 08/14/2019] [Indexed: 06/10/2023]
Abstract
The need to prevent possible adverse environmental health impacts resulting from synthetic biology (SynBio) products is widely acknowledged in both the SynBio risk literature and the global regulatory community. To-date, however, discussions of potential risks of SynBio products have been largely speculative, and the limited attempts to characterize the risks of SynBio products have been non-uniform and entirely qualitative. As the SynBio discipline continues to accelerate and bring forth novel, highly-engineered life forms, a standardized risk assessment framework will become critical for ensuring that the environmental risks of these products are characterized in a consistent, reliable, and objective manner that incorporates all SynBio-unique risk factors. In their current forms, established risk assessment frameworks - including those that address traditional genetically modified organisms - fall short of the features required of this standard framework. To address this gap, we propose the Quantitative Risk Assessment Method for Synthetic Biology Products (QRA-SynBio) - an incremental build on established risk assessment methodologies that supplements traditional paradigms with the SynBio risk factors that are currently absent, and necessitates quantitative analysis for more transparent and objective risk characterizations. We demonstrate through a hypothetical case study that the proposed framework facilitates defensible quantification of the environmental risks of SynBio products in both foreseeable and hypothetical use scenarios. Additionally, we show how the quantitative nature of the proposed method can promote increased experimental investigation into the true likelihood of hazard and exposure parameters and highlight the most sensitive parameters where uncertainty should be reduced, ultimately leading to more targeted SynBio risk research and yielding more precise characterizations of risk.
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Affiliation(s)
- Taylor Rycroft
- Environmental Laboratory, U.S. Army Engineer Research and Development Center, Concord, MA, USA.
| | - Kerry Hamilton
- School for Sustainable Engineering and the Built Environment & The Biodesign Institute Center for Environmental Health Engineering, Arizona State University, Tempe, AZ, USA
| | - Charles N Haas
- Department of Civil, Architectural and Environmental Engineering, Drexel University, Philadelphia, PA, USA
| | - Igor Linkov
- Environmental Laboratory, U.S. Army Engineer Research and Development Center, Concord, MA, USA
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10
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Samodelov SL, Zurbriggen MD. Quantitatively Understanding Plant Signaling: Novel Theoretical-Experimental Approaches. TRENDS IN PLANT SCIENCE 2017; 22:685-704. [PMID: 28668509 DOI: 10.1016/j.tplants.2017.05.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2016] [Revised: 05/15/2017] [Accepted: 05/16/2017] [Indexed: 06/07/2023]
Abstract
With the need to respond to and integrate a multitude of external and internal stimuli, plant signaling is highly complex, exhibiting signaling component redundancy and high interconnectedness between individual pathways. We review here novel theoretical-experimental approaches in manipulating plant signaling towards the goal of a comprehensive understanding and targeted quantitative control of plant processes. We highlight approaches taken in the field of synthetic biology used in other systems and discuss their applicability in plants. Finally, we introduce existing tools for the quantitative analysis and monitoring of plant signaling and the integration of experimentally obtained quantitative data into mathematical models. Incorporating principles of synthetic biology into plant sciences more widely will lead this field forward in both fundamental and applied research.
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Affiliation(s)
- Sophia L Samodelov
- Institute of Synthetic Biology and Cluster of Excellence on Plant Sciences (CEPLAS), University of Düsseldorf, Düsseldorf, Germany; Spemann Graduate School of Biology and Medicine (SGBM), University of Freiburg, Freiburg, Germany
| | - Matias D Zurbriggen
- Institute of Synthetic Biology and Cluster of Excellence on Plant Sciences (CEPLAS), University of Düsseldorf, Düsseldorf, Germany.
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11
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Synthetic genetic circuits in crop plants. Curr Opin Biotechnol 2017; 49:16-22. [PMID: 28772191 DOI: 10.1016/j.copbio.2017.07.003] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 06/26/2017] [Accepted: 07/03/2017] [Indexed: 11/22/2022]
Abstract
The love affair between crop breeding and genetics began over a century ago and has continued unabated, from mass selection programs to targeted genome modifications. Synthetic genetic circuits, a recent development, are combinations of regulatory and coding DNA introduced into a crop plant to achieve a desired function. Genetic circuits could accelerate crop improvement, allowing complex traits to be rationally designed and requisite DNA parts delivered directly into a genome of interest. However, there is not yet a standardized pipeline from exploratory laboratory testing to crop trials, and bringing transgenic products to market remains a considerable barrier. We highlight successes so far and future developments necessary to make genetic circuits a viable crop improvement technology over this century.
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12
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Abstract
New technologies are redefining how plant biology will meet societal challenges in health, nutrition, agriculture, and energy. Rapid and inexpensive genome and transcriptome sequencing is being exploited to discover biochemical pathways that provide tools needed for synthetic biology in both plant and microbial systems. Metabolite detection at the cellular and subcellular levels is complementing gene sequencing for pathway discovery and metabolic engineering. The crafting of plant and microbial metabolism for the synthetic biology platforms of tomorrow will require precise gene editing and delivery of entire complex pathways. Plants sustain life and are key to discovery and development of new medicines and agricultural resources; increased research and training in plant science will accelerate efforts to harness the chemical wealth of the plant kingdom.
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Affiliation(s)
- Eleanore T Wurtzel
- Department of Biological Sciences, Lehman College, The City University of New York, 250 Bedford Park Boulevard West, Bronx, NY 10468, USA. The Graduate School and University Center-CUNY, 365 Fifth Avenue, New York, NY 10016-4309, USA.
| | - Toni M Kutchan
- Donald Danforth Plant Science Center, 975 North Warson Road, St. Louis, MO 63132, USA.
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13
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Shih PM, Liang Y, Loqué D. Biotechnology and synthetic biology approaches for metabolic engineering of bioenergy crops. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2016; 87:103-17. [PMID: 27030440 DOI: 10.1111/tpj.13176] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2015] [Revised: 03/18/2016] [Accepted: 03/22/2016] [Indexed: 05/26/2023]
Abstract
The Green Revolution has fuelled an exponential growth in human population since the mid-20th century. Due to population growth, food and energy demands will soon surpass supply capabilities. To overcome these impending problems, significant improvements in genetic engineering will be needed to complement breeding efforts in order to accelerate the improvement of agronomical traits. The new field of plant synthetic biology has emerged in recent years and is expected to support rapid, precise, and robust engineering of plants. In this review, we present recent advances made in the field of plant synthetic biology, specifically in genome editing, transgene expression regulation, and bioenergy crop engineering, with a focus on traits related to lignocellulose, oil, and soluble sugars. Ultimately, progress and innovation in these fields may facilitate the development of beneficial traits in crop plants to meet society's bioenergy needs.
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Affiliation(s)
- Patrick M Shih
- Joint BioEnergy Institute, Emery Station East, 5885 Hollis St, 4th Floor, Emeryville, CA, 94608, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA, 94720, USA
| | - Yan Liang
- Joint BioEnergy Institute, Emery Station East, 5885 Hollis St, 4th Floor, Emeryville, CA, 94608, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA, 94720, USA
| | - Dominique Loqué
- Joint BioEnergy Institute, Emery Station East, 5885 Hollis St, 4th Floor, Emeryville, CA, 94608, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA, 94720, USA
- Université Lyon 1, INSA de Lyon, CNRS, UMR5240, Microbiologie, Adaptation et Pathogénie, 10 rue Raphaël Dubois, F-69622, Villeurbanne, France
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14
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Puchta H. Using CRISPR/Cas in three dimensions: towards synthetic plant genomes, transcriptomes and epigenomes. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2016; 87:5-15. [PMID: 26677816 DOI: 10.1111/tpj.13100] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Revised: 11/23/2015] [Accepted: 11/25/2015] [Indexed: 05/21/2023]
Abstract
It is possible to target individual sequence motives within genomes by using synthetic DNA-binding domains. This one-dimensional approach has been used successfully in plants to induce mutations or for the transcriptional regulation of single genes. When the CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 system was discovered, a tool became available allowing the extension of this approach from one to three dimensions and to construct at least partly synthetic entities on the genome, epigenome and transcriptome levels. The second dimension can be obtained by targeting the Cas9 protein to multiple unique genomic sites by applying multiple different single guiding (sg) RNAs, each defining a different DNA-binding site. Finally, the simultaneous use of phylogenetically different Cas9 proteins or sgRNAs that harbour different types of protein binding motives, allows for a third dimension of control. Thus, different types of enzyme activities - fused either to one type of Cas9 orthologue or to one type of RNA-binding domain specific to one type of sgRNA - can be targeted to multiple different genomic sites simultaneously. Thus, it should be possible to induce quantitatively different levels of expression of certain sets of genes and at the same time to repress other genes, redefining the nuclear transcriptome. Likewise, by the use of different types of histone-modifying and/or DNA (de)methylating activities, the epigenome of plants should be reprogrammable. On our way to synthetic plant genomes, the next steps will be to use complex genome engineering approaches within or between species borders to restructure and recombine natural or artificial chromosomes.
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Affiliation(s)
- Holger Puchta
- Botanical Institute II, Karlsruhe Institute of Technology, POB 6980, 76049, Karlsruhe, Germany
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15
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Generation of a Maize B Centromere Minimal Map Containing the Central Core Domain. G3-GENES GENOMES GENETICS 2015; 5:2857-64. [PMID: 26511496 PMCID: PMC4683656 DOI: 10.1534/g3.115.022889] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The maize B centromere has been used as a model for centromere epigenetics and as the basis for building artificial chromosomes. However, there are no sequence resources for this important centromere. Here we used transposon display for the centromere-specific retroelement CRM2 to identify a collection of 40 sequence tags that flank CRM2 insertion points on the B chromosome. These were confirmed to lie within the centromere by assaying deletion breakpoints from centromere misdivision derivatives (intracentromere breakages caused by centromere fission). Markers were grouped together on the basis of their association with other markers in the misdivision series and assembled into a pseudocontig containing 10.1 kb of sequence. To identify sequences that interact directly with centromere proteins, we carried out chromatin immunoprecipitation using antibodies to centromeric histone H3 (CENH3), a defining feature of functional centromeric sequences. The CENH3 chromatin immunoprecipitation map was interpreted relative to the known transmission rates of centromere misdivision derivatives to identify a centromere core domain spanning 33 markers. A subset of seven markers was mapped in additional B centromere misdivision derivatives with the use of unique primer pairs. A derivative previously shown to have no canonical centromere sequences (Telo3-3) lacks these core markers. Our results provide a molecular map of the B chromosome centromere and identify key sequences within the map that interact directly with centromeric histone H3.
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16
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Schindler D, Waldminghaus T. Synthetic chromosomes. FEMS Microbiol Rev 2015; 39:871-91. [DOI: 10.1093/femsre/fuv030] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/26/2015] [Indexed: 12/22/2022] Open
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