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Yang Y, Chaffin TA, Shao Y, Balasubramanian VK, Markillie M, Mitchell H, Rubio‐Wilhelmi MM, Ahkami AH, Blumwald E, Neal Stewart C. Novel synthetic inducible promoters controlling gene expression during water-deficit stress with green tissue specificity in transgenic poplar. PLANT BIOTECHNOLOGY JOURNAL 2024; 22:1596-1609. [PMID: 38232002 PMCID: PMC11123411 DOI: 10.1111/pbi.14289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Revised: 11/16/2023] [Accepted: 01/03/2024] [Indexed: 01/19/2024]
Abstract
Synthetic promoters may be designed using short cis-regulatory elements (CREs) and core promoter sequences for specific purposes. We identified novel conserved DNA motifs from the promoter sequences of leaf palisade and vascular cell type-specific expressed genes in water-deficit stressed poplar (Populus tremula × Populus alba), collected through low-input RNA-seq analysis using laser capture microdissection. Hexamerized sequences of four conserved 20-base motifs were inserted into each synthetic promoter construct. Two of these synthetic promoters (Syn2 and Syn3) induced GFP in transformed poplar mesophyll protoplasts incubated in 0.5 M mannitol solution. To identify effect of length and sequence from a valuable 20 base motif, 5' and 3' regions from a basic sequence (GTTAACTTCAGGGCCTGTGG) of Syn3 were hexamerized to generate two shorter synthetic promoters, Syn3-10b-1 (5': GTTAACTTCA) and Syn3-10b-2 (3': GGGCCTGTGG). These promoters' activities were compared with Syn3 in plants. Syn3 and Syn3-10b-1 were specifically induced in transient agroinfiltrated Nicotiana benthamiana leaves in water cessation for 3 days. In stable transgenic poplar, Syn3 presented as a constitutive promoter but had the highest activity in leaves. Syn3-10b-1 had stronger induction in green tissues under water-deficit stress conditions than mock control. Therefore, a synthetic promoter containing the 5' sequence of Syn3 endowed both tissue-specificity and water-deficit inducibility in transgenic poplar, whereas the 3' sequence did not. Consequently, we have added two new synthetic promoters to the poplar engineering toolkit: Syn3-10b-1, a green tissue-specific and water-deficit stress-induced promoter, and Syn3, a green tissue-preferential constitutive promoter.
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Affiliation(s)
- Yongil Yang
- Center for Agricultural Synthetic BiologyUniversity of Tennessee Institute of AgricultureKnoxvilleTennesseeUSA
| | - Timothy A. Chaffin
- Center for Agricultural Synthetic BiologyUniversity of Tennessee Institute of AgricultureKnoxvilleTennesseeUSA
| | - Yuanhua Shao
- Center for Agricultural Synthetic BiologyUniversity of Tennessee Institute of AgricultureKnoxvilleTennesseeUSA
- Department of Plant SciencesUniversity of TennesseeKnoxvilleTennesseeUSA
| | | | - Meng Markillie
- Environmental Molecular Sciences Laboratory, Pacific Northwest National LaboratoryRichlandWAUSA
| | - Hugh Mitchell
- Environmental Molecular Sciences Laboratory, Pacific Northwest National LaboratoryRichlandWAUSA
| | | | - Amir H. Ahkami
- Environmental Molecular Sciences Laboratory, Pacific Northwest National LaboratoryRichlandWAUSA
| | - Eduardo Blumwald
- Department of Plant SciencesUniversity of CaliforniaDavisCaliforniaUSA
| | - C. Neal Stewart
- Center for Agricultural Synthetic BiologyUniversity of Tennessee Institute of AgricultureKnoxvilleTennesseeUSA
- Department of Plant SciencesUniversity of TennesseeKnoxvilleTennesseeUSA
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Bibik JD, Sahu A, Kim B, Unda F, Andersen TB, Mansfield SD, Maravelias CT, Sharkey TD, Hamberger BR. Engineered poplar for bioproduction of the triterpene squalene. PLANT BIOTECHNOLOGY JOURNAL 2024. [PMID: 38507185 DOI: 10.1111/pbi.14345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 12/30/2023] [Accepted: 03/10/2024] [Indexed: 03/22/2024]
Abstract
Building sustainable platforms to produce biofuels and specialty chemicals has become an increasingly important strategy to supplement and replace fossil fuels and petrochemical-derived products. Terpenoids are the most diverse class of natural products that have many commercial roles as specialty chemicals. Poplar is a fast growing, biomassdense bioenergy crop with many species known to produce large amounts of the hemiterpene isoprene, suggesting an inherent capacity to produce significant quantities of other terpenes. Here we aimed to engineer poplar with optimized pathways to produce squalene, a triterpene commonly used in cosmetic oils, a potential biofuel candidate, and the precursor to the further diversified classes of triterpenoids and sterols. The squalene production pathways were either re-targeted from the cytosol to plastids or co-produced with lipid droplets in the cytosol. Squalene and lipid droplet co-production appeared to be toxic, which we hypothesize to be due to disruption of adventitious root formation, suggesting a need for tissue specific production. Plastidial squalene production enabled up to 0.63 mg/g fresh weight in leaf tissue, which also resulted in reductions in isoprene emission and photosynthesis. These results were also studied through a technoeconomic analysis, providing further insight into developing poplar as a production host.
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Affiliation(s)
- Jacob D Bibik
- Cell and Molecular Biology Program, Michigan State University, East Lansing, Michigan, USA
- DOE Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, Michigan, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA
| | - Abira Sahu
- DOE Plant Research Laboratory, Michigan State University, East Lansing, Michigan, USA
- The Plant Resilience Institute, Michigan State University, East Lansing, Michigan, USA
| | - Boeun Kim
- DOE Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, Michigan, USA
- Andlinger Center for Energy and the Environment, Princeton University, Princeton, New Jersey, USA
| | - Faride Unda
- DOE Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, Michigan, USA
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, British Columbia, Canada
| | - Trine B Andersen
- DOE Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, Michigan, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA
| | - Shawn D Mansfield
- DOE Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, Michigan, USA
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Botany, Faculty of Science, University of British Columbia, Vancouver, British Columbia, Canada
| | - Christos T Maravelias
- Andlinger Center for Energy and the Environment, Princeton University, Princeton, New Jersey, USA
- Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey, USA
| | - Thomas D Sharkey
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA
- DOE Plant Research Laboratory, Michigan State University, East Lansing, Michigan, USA
- The Plant Resilience Institute, Michigan State University, East Lansing, Michigan, USA
| | - Björn R Hamberger
- Cell and Molecular Biology Program, Michigan State University, East Lansing, Michigan, USA
- DOE Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, Michigan, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA
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3
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Song Q, Kong L, Yang X, Jiao B, Hu J, Zhang Z, Xu C, Luo K. PtoMYB142, a poplar R2R3-MYB transcription factor, contributes to drought tolerance by regulating wax biosynthesis. TREE PHYSIOLOGY 2022; 42:2133-2147. [PMID: 35640137 DOI: 10.1093/treephys/tpac060] [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: 03/18/2022] [Accepted: 05/19/2022] [Indexed: 06/15/2023]
Abstract
Drought is one of the main environmental factors that limit plant development and growth. Accordingly, plants have evolved strategies to prevent water loss under drought stress, such as stomatal closure, maintenance of root water uptake, enhancement of stem water transport, and synthesis and deposition of cuticular wax. However, the molecular evidence of cuticular wax biosynthesis regulation in response to drought is limited in woody plants. Here, we identified an MYB transcription factor, Populus tomentosa Carr. MYB transcription factor (PtoMYB142), in response to drought stress from P. tomentosa. Over-expression of PtoMYB142 (PtoMYB142-OE) resulted in increased wax accumulation in poplar leaves, and significantly enhanced drought resistance. We found that the expression of wax biosynthesis genes CER4 and 3-ketoacyl CoA synthase (KCS) were markedly induced under drought stress, and significantly up-regulated in PtoMYB142-OE lines. Biochemical analysis confirmed that PtoMYB142 could directly bind to the promoter of CER4 and KCS6, and regulate their expression in P. tomentosa. Taken together, this study reveals that PtoMYB142 regulates cuticular wax biosynthesis to adapt to water-deficient conditions.
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Affiliation(s)
- Qin Song
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, School of Life Sciences, Southwest University, Chongqing 400715, China
- Key Laboratory of Eco-environments of Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Lingfei Kong
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Xuerui Yang
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Bo Jiao
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, School of Life Sciences, Southwest University, Chongqing 400715, China
- Institute of Biotechnology and Food Science, Hebei Academy of Agriculture and Forestry Sciences, Shijiazhuang 050051, China
| | - Jian Hu
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Zhichao Zhang
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Changzheng Xu
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, School of Life Sciences, Southwest University, Chongqing 400715, China
- Key Laboratory of Eco-environments of Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Keming Luo
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, School of Life Sciences, Southwest University, Chongqing 400715, China
- Key Laboratory of Eco-environments of Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China
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Xu H, Giannetti A, Sugiyama Y, Zheng W, Schneider R, Watanabe Y, Oda Y, Persson S. Secondary cell wall patterning-connecting the dots, pits and helices. Open Biol 2022; 12:210208. [PMID: 35506204 PMCID: PMC9065968 DOI: 10.1098/rsob.210208] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 04/07/2022] [Indexed: 01/04/2023] Open
Abstract
All plant cells are encased in primary cell walls that determine plant morphology, but also protect the cells against the environment. Certain cells also produce a secondary wall that supports mechanically demanding processes, such as maintaining plant body stature and water transport inside plants. Both these walls are primarily composed of polysaccharides that are arranged in certain patterns to support cell functions. A key requisite for patterned cell walls is the arrangement of cortical microtubules that may direct the delivery of wall polymers and/or cell wall producing enzymes to certain plasma membrane locations. Microtubules also steer the synthesis of cellulose-the load-bearing structure in cell walls-at the plasma membrane. The organization and behaviour of the microtubule array are thus of fundamental importance to cell wall patterns. These aspects are controlled by the coordinated effort of small GTPases that probably coordinate a Turing's reaction-diffusion mechanism to drive microtubule patterns. Here, we give an overview on how wall patterns form in the water-transporting xylem vessels of plants. We discuss systems that have been used to dissect mechanisms that underpin the xylem wall patterns, emphasizing the VND6 and VND7 inducible systems, and outline challenges that lay ahead in this field.
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Affiliation(s)
- Huizhen Xu
- School of Biosciences, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Alessandro Giannetti
- Department of Plant and Environmental Sciences, University of Copenhagen, 1871 Frederiksberg C, Denmark
| | - Yuki Sugiyama
- The Sainsbury Laboratory, University of Cambridge, Bateman Street, Cambridge CB2 1LR, UK
| | - Wenna Zheng
- School of Biosciences, The University of Melbourne, Parkville, Victoria 3010, Australia
- Department of Plant and Environmental Sciences, University of Copenhagen, 1871 Frederiksberg C, Denmark
| | - René Schneider
- Institute of Biochemistry and Biology, Plant Physiology Department, University of Potsdam, 14476 Potsdam, Germany
| | - Yoichiro Watanabe
- Institute for Research Initiatives, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan
| | - Yoshihisa Oda
- Department of Gene Function and Phenomics, National Institute of Genetics, 1111 Yata, Mishima, Shizuoka 411-8540, Japan
- Department of Genetics, The Graduate University for Advanced Studies, SOKENDAI, 1111 Yata, Mishima, Shizuoka 411-8540, Japan
| | - Staffan Persson
- School of Biosciences, The University of Melbourne, Parkville, Victoria 3010, Australia
- Department of Plant and Environmental Sciences, University of Copenhagen, 1871 Frederiksberg C, Denmark
- Copenhagen Plant Science Center, University of Copenhagen, 1871 Frederiksberg C, Denmark
- Joint International Research Laboratory of Metabolic and Developmental Sciences, State Key Laboratory of Hybrid Rice, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, People's Republic of China
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Ahlawat YK, Nookaraju A, Harman-Ware AE, Doeppke C, Biswal AK, Joshi CP. Genetic Modification of KNAT7 Transcription Factor Expression Enhances Saccharification and Reduces Recalcitrance of Woody Biomass in Poplars. FRONTIERS IN PLANT SCIENCE 2021; 12:762067. [PMID: 34795688 PMCID: PMC8594486 DOI: 10.3389/fpls.2021.762067] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 10/06/2021] [Indexed: 06/13/2023]
Abstract
The precise role of KNAT7 transcription factors (TFs) in regulating secondary cell wall (SCW) biosynthesis in poplars has remained unknown, while our understanding of KNAT7 functions in other plants is continuously evolving. To study the impact of genetic modifications of homologous and heterologous KNAT7 gene expression on SCW formation in transgenic poplars, we prepared poplar KNAT7 (PtKNAT7) overexpression (PtKNAT7-OE) and antisense suppression (PtKNAT7-AS) vector constructs for the generation of transgenic poplar lines via Agrobacterium-mediated transformation. Since the overexpression of homologous genes can sometimes result in co-suppression, we also overexpressed Arabidopsis KNAT7 (AtKNAT7-OE) in transgenic poplars. In all these constructs, the expression of KNAT7 transgenes was driven by developing xylem (DX)-specific promoter, DX15. Compared to wild-type (WT) controls, many SCW biosynthesis genes downstream of KNAT7 were highly expressed in poplar PtKNAT7-OE and AtKNAT7-OE lines. Yet, no significant increase in lignin content of woody biomass of these transgenic lines was observed. PtKNAT7-AS lines, however, showed reduced expression of many SCW biosynthesis genes downstream of KNAT7 accompanied by a reduction in lignin content of wood compared to WT controls. Syringyl to Guaiacyl lignin (S/G) ratios were significantly increased in all three KNAT7 knockdown and overexpression transgenic lines than WT controls. These transgenic lines were essentially indistinguishable from WT controls in terms of their growth phenotype. Saccharification efficiency of woody biomass was significantly increased in all transgenic lines than WT controls. Overall, our results demonstrated that developing xylem-specific alteration of KNAT7 expression affects the expression of SCW biosynthesis genes, impacting at least the lignification process and improving saccharification efficiency, hence providing one of the powerful tools for improving bioethanol production from woody biomass of bioenergy crops and trees.
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Affiliation(s)
- Yogesh Kumar Ahlawat
- Department of Biological Sciences, Michigan Technological University, Houghton, MI, United States
- Department of Horticultural Sciences, University of Florida, Gainesville, FL, United States
| | | | - Anne E. Harman-Ware
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, United States
| | - Crissa Doeppke
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, United States
| | - Ajaya K. Biswal
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, United States
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, United States
| | - Chandrashekhar P. Joshi
- Department of Biological Sciences, Michigan Technological University, Houghton, MI, United States
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Cho JS, Kim MH, Bae EK, Choi YI, Jeon HW, Han KH, Ko JH. Field evaluation of transgenic hybrid poplars with desirable wood properties and enhanced growth for biofuel production by bicistronic expression of PdGA20ox1 and PtrMYB3 in wood-forming tissue. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:177. [PMID: 34493336 PMCID: PMC8425128 DOI: 10.1186/s13068-021-02029-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 08/28/2021] [Indexed: 06/12/2023]
Abstract
BACKGROUND To create an ideotype woody bioenergy crop with desirable growth and biomass properties, we utilized the viral 2A-meidated bicistronic expression strategy to express both PtrMYB3 (MYB46 ortholog of Populus trichocarpa, a master regulator of secondary wall biosynthesis) and PdGA20ox1 (a GA20-oxidase from Pinus densiflora that produces gibberellins) in wood-forming tissue (i.e., developing xylem). RESULTS Transgenic Arabidopsis plants expressing the gene construct DX15::PdGA20ox1-2A-PtrMYB3 showed a significant increase in both stem fresh weight (threefold) and secondary wall thickening (1.27-fold) relative to wild-type (WT) plants. Transgenic poplars harboring the same gene construct grown in a greenhouse for 60 days had a stem fresh weight up to 2.6-fold greater than that of WT plants. In a living modified organism (LMO) field test conducted for 3 months of active growing season, the stem height and diameter growth of the transgenic poplars were 1.7- and 1.6-fold higher than those of WT plants, respectively, with minimal adverse growth defects. Although no significant changes in secondary wall thickening of the stem tissue of the transgenic poplars were observed, cellulose content was increased up to 14.4 wt% compared to WT, resulting in improved saccharification efficiency of the transgenic poplars. Moreover, enhanced woody biomass production by the transgenic poplars was further validated by re-planting in the same LMO field for additional two growing seasons. CONCLUSIONS Taken together, these results show considerably enhanced wood formation of our transgenic poplars, with improved wood quality for biofuel production.
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Affiliation(s)
- Jin-Seong Cho
- Department of Plant & Environmental New Resources, Kyung Hee University, 446-701, Yongin, Republic of Korea
- Abio Materials Co., Ltd, Cheonan, 31005, Republic of Korea
| | - Min-Ha Kim
- Department of Plant & Environmental New Resources, Kyung Hee University, 446-701, Yongin, Republic of Korea
| | - Eun-Kyung Bae
- Division of Forest Biotechnology, National Institute of Forest Science, 441-847, Suwon, Republic of Korea
| | - Young-Im Choi
- Division of Forest Biotechnology, National Institute of Forest Science, 441-847, Suwon, Republic of Korea
| | - Hyung-Woo Jeon
- Department of Plant & Environmental New Resources, Kyung Hee University, 446-701, Yongin, Republic of Korea
| | - Kyung-Hwan Han
- Department of Horticulture and Department of Forestry, Michigan State University, East Lansing, MI, 48824-1222, USA.
| | - Jae-Heung Ko
- Department of Plant & Environmental New Resources, Kyung Hee University, 446-701, Yongin, Republic of Korea.
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Kim MH, Tran TNA, Cho JS, Park EJ, Lee H, Kim DG, Hwang S, Ko JH. Wood transcriptome analysis of Pinus densiflora identifies genes critical for secondary cell wall formation and NAC transcription factors involved in tracheid formation. TREE PHYSIOLOGY 2021; 41:1289-1305. [PMID: 33440425 DOI: 10.1093/treephys/tpab001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 01/04/2021] [Indexed: 05/27/2023]
Abstract
Although conifers have significant ecological and economic value, information on transcriptional regulation of wood formation in conifers is still limited. Here, to gain insight into secondary cell wall (SCW) biosynthesis and tracheid formation in conifers, we performed wood tissue-specific transcriptome analyses of Pinus densiflora (Korean red pine) using RNA sequencing. In addition, to obtain full-length transcriptome information, PacBio single molecule real-time iso-sequencing was carried out using RNAs from 28 tissues of P. densiflora. Subsequent comparative tissue-specific transcriptome analysis successfully pinpointed critical genes encoding key proteins involved in biosynthesis of the major secondary wall components (cellulose, galactoglucomannan, xylan and lignin). Furthermore, we predicted a total of 62 NAC (NAM, ATAF1/2 and CUC2) family transcription factor members and identified seven PdeNAC genes preferentially expressed in developing xylem tissues in P. densiflora. Protoplast-based transcriptional activation analysis found that four PdeNAC genes, homologous to VND, NST and SND/ANAC075, upregulated GUS activity driven by an SCW-specific cellulose synthase promoter. Consistently, transient overexpression of the four PdeNACs induced xylem vessel cell-like SCW deposition in both tobacco (Nicotiana benthamiana) and Arabidopsis leaves. Taken together, our data provide a foundation for further research to unravel transcriptional regulation of wood formation in conifers, especially SCW formation and tracheid differentiation.
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Affiliation(s)
- Min-Ha Kim
- Department of Plant & Environmental New Resources, Kyung Hee University, 1732 Deogyeong-daero, Yongin 17104, Republic of Korea
| | - Thi Ngoc Anh Tran
- Department of Plant & Environmental New Resources, Kyung Hee University, 1732 Deogyeong-daero, Yongin 17104, Republic of Korea
| | - Jin-Seong Cho
- Department of Plant & Environmental New Resources, Kyung Hee University, 1732 Deogyeong-daero, Yongin 17104, Republic of Korea
| | - Eung-Jun Park
- Division of Forest Biotechnology, National Institute of Forest Science, 39 Onjeong-ro, Suwon 16631, Republic of Korea
| | - Hyoshin Lee
- Division of Forest Biotechnology, National Institute of Forest Science, 39 Onjeong-ro, Suwon 16631, Republic of Korea
| | - Dong-Gwan Kim
- Department of Bioindustry and Bioresource Engineering, Department of Molecular Biology and Plant Engineering Research Institute, Sejong University, 209 Neungdong-ro, Seoul 05006, Republic of Korea
| | - Seongbin Hwang
- Department of Bioindustry and Bioresource Engineering, Department of Molecular Biology and Plant Engineering Research Institute, Sejong University, 209 Neungdong-ro, Seoul 05006, Republic of Korea
| | - Jae-Heung Ko
- Department of Plant & Environmental New Resources, Kyung Hee University, 1732 Deogyeong-daero, Yongin 17104, Republic of Korea
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Cao Y, Xu X, Jiang L. Integrative analysis of the RNA interference toolbox in two Salicaceae willow species, and their roles in stress response in poplar (Populus trichocarpa Torr. & Gray). Int J Biol Macromol 2020; 162:1127-1139. [DOI: 10.1016/j.ijbiomac.2020.06.235] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 05/31/2020] [Accepted: 06/24/2020] [Indexed: 10/24/2022]
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9
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Han X, An Y, Zhou Y, Liu C, Yin W, Xia X. Comparative transcriptome analyses define genes and gene modules differing between two Populus genotypes with contrasting stem growth rates. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:139. [PMID: 32782475 PMCID: PMC7415184 DOI: 10.1186/s13068-020-01758-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 06/29/2020] [Indexed: 05/04/2023]
Abstract
BACKGROUND Wood provides an important biomass resource for biofuel production around the world. The radial growth of tree stems is central to biomass production for forestry and biofuels, but it is challenging to dissect genetically because it is a complex trait influenced by many genes. In this study, we adopted methods of physiology, transcriptomics and genetics to investigate the regulatory mechanisms of tree radial growth and wood development. RESULTS Physiological comparison showed that two Populus genotypes presented different rates of radial growth of stems and accumulation of woody biomass. A comparative transcriptional network approach was used to define and characterize functional differences between two Populus genotypes. Analyses of transcript profiles from wood-forming tissue of the two genotypes showed that 1542, 2295 and 2110 genes were differentially expressed in the pre-growth, fast-growth and post-growth stages, respectively. The co-expression analyses identified modules of co-expressed genes that displayed distinct expression profiles. Modules were further characterized by correlating transcript levels with genotypes and physiological traits. The results showed enrichment of genes that participated in cell cycle and division, whose expression change was consistent with the variation of radial growth rates. Genes related to secondary vascular development were up-regulated in the faster-growing genotype in the pre-growth stage. We characterized a BEL1-like (BELL) transcription factor, PeuBELL15, which was up-regulated in the faster-growing genotype. Analyses of transgenic Populus overexpressing as well as CRISPR/Cas9-induced mutants for BELL15 showed that PeuBELL15 improved accumulation of glucan and lignin, and it promoted secondary vascular growth by regulating the expression of genes relevant for cellulose synthases and lignin biosynthesis. CONCLUSIONS This study illustrated that active division and expansion of vascular cambium cells and secondary cell wall deposition of xylem cells contribute to stem radial increment and biomass accumulation, and it identified relevant genes for these complex growth traits, including a BELL transcription factor gene PeuBELL15. This provides genetic resources for improving and breeding elite genotypes with fast growth and high wood biomass.
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Affiliation(s)
- Xiao Han
- State Key Laboratory of Subtropical Silviculture, College of Forestry and Biotechnology, Zhejiang A&F University, Lin’an, Hangzhou, 311300 China
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083 China
| | - Yi An
- Sino-Australia Plant Cell Wall Research Centre, State Key Laboratory of Subtropical Silviculture, College of Forestry and Biotechnology, Zhejiang A&F University, Lin’an, Hangzhou, 311300 China
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083 China
| | - Yangyan Zhou
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083 China
| | - Chao Liu
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083 China
| | - Weilun Yin
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083 China
| | - Xinli Xia
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083 China
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Patatin-Related Phospholipase AtpPLAIIIα Affects Lignification of Xylem in Arabidopsis and Hybrid Poplars. PLANTS 2020; 9:plants9040451. [PMID: 32260242 PMCID: PMC7238252 DOI: 10.3390/plants9040451] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 04/01/2020] [Accepted: 04/02/2020] [Indexed: 12/21/2022]
Abstract
Lipid acyl hydrolase are a diverse group of enzymes that hydrolyze the ester or amide bonds of fatty acid in plant lipids. Patatin-related phospholipase AIIIs (pPLAIIIs) are one of major lipid acyl hydrolases that are less closely related to potato tuber patatins and are plant-specific. Recently, overexpression of ginseng-derived PgpPLAIIIβ was reported to be involved in the reduced level of lignin content in Arabidopsis and the mature xylem layer of poplar. The presence of lignin-polysaccharides renders cell walls recalcitrant for pulping and biofuel production. The tissue-specific regulation of lignin biosynthesis, without altering all xylem in plants, can be utilized usefully by keeping mechanical strength and resistance to various environmental stimuli. To identify another pPLAIII homolog from Arabidopsis, constitutively overexpressed AtpPLAIIIα was characterized for xylem lignification in two well-studied model plants, Arabidopsis and poplar. The characterization of gene function in annual and perennial plants with respect to lignin biosynthesis revealed the functional redundancy of less lignification via downregulation of lignin biosynthesis-related genes.
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Li Y, Dong C, Hu M, Bai Z, Tong C, Zuo R, Liu Y, Cheng X, Cheng M, Huang J, Liu S. Identification of Flower-Specific Promoters through Comparative Transcriptome Analysis in Brassica napus. Int J Mol Sci 2019; 20:ijms20235949. [PMID: 31779216 PMCID: PMC6928827 DOI: 10.3390/ijms20235949] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 11/20/2019] [Accepted: 11/25/2019] [Indexed: 01/24/2023] Open
Abstract
Brassica napus (oilseed rape) is an economically important oil crop worldwide. Sclerotinia stem rot (SSR) caused by Sclerotinia sclerotiorum is a threat to oilseed rape production. Because the flower petals play pivotal roles in the SSR disease cycle, it is useful to express the resistance-related genes specifically in flowers to hinder further infection with S. sclerotiorum. To screen flower-specific promoters, we first analyzed the transcriptome data from 12 different tissues of the B. napus line ZS11. In total, 249 flower-specific candidate genes with high expression in petals were identified, and the expression patterns of 30 candidate genes were verified by quantitative real-time transcription-PCR (qRT-PCR) analysis. Furthermore, two novel flower-specific promoters (FSP046 and FSP061 promoter) were identified, and the tissue specificity and continuous expression in petals were determined in transgenic Arabidopsis thaliana with fusing the promoters to β-glucuronidase (GUS)-reporter gene. GUS staining, transcript expression pattern, and GUS activity analysis indicated that FSP046 and FSP061 promoter were strictly flower-specific promoters, and FSP046 promoter had a stronger activity. The two promoters were further confirmed to be able to direct GUS expression in B. napus flowers using transient expression system. The transcriptome data and the flower-specific promoters screened in the present study will benefit fundamental research for improving the agronomic traits as well as disease and pest control in a tissue-specific manner.
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Kim MH, Cho JS, Jeon HW, Sangsawang K, Shim D, Choi YI, Park EJ, Lee H, Ko JH. Wood Transcriptome Profiling Identifies Critical Pathway Genes of Secondary Wall Biosynthesis and Novel Regulators for Vascular Cambium Development in Populus. Genes (Basel) 2019; 10:E690. [PMID: 31500311 PMCID: PMC6770981 DOI: 10.3390/genes10090690] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 09/02/2019] [Accepted: 09/04/2019] [Indexed: 12/23/2022] Open
Abstract
Wood, the most abundant biomass on Earth, is composed of secondary xylem differentiated from vascular cambium. However, the underlying molecular mechanisms of wood formation remain largely unclear. To gain insight into wood formation, we performed a series of wood-forming tissue-specific transcriptome analyses from a hybrid poplar (Populus alba × P. glandulosa, clone BH) using RNA-seq. Together with shoot apex and leaf tissue, cambium and xylem tissues were isolated from vertical stem segments representing a gradient of secondary growth developmental stages (i.e., immature, intermediate, and mature stem). In a comparative transcriptome analysis of the 'developing xylem' and 'leaf' tissue, we could identify critical players catalyzing each biosynthetic step of secondary wall components (e.g., cellulose, xylan, and lignin). Several candidate genes involved in the initiation of vascular cambium formation were found via a co-expression network analysis using abundantly expressed genes in the 'intermediate stem-derived cambium' tissue. We found that transgenic Arabidopsis plants overexpressing the PtrHAM4-1, a GRAS family transcription factor, resulted in a significant increase of vascular cambium development. This phenotype was successfully reproduced in the transgenic poplars overexpressing the PtrHAM4-1. Taken together, our results may serve as a springboard for further research to unravel the molecular mechanism of wood formation, one of the most important biological processes on this planet.
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Affiliation(s)
- Min-Ha Kim
- Department of Plant & Environmental New Resources, Kyung Hee University, Yongin 446-701, Korea.
| | - Jin-Seong Cho
- Department of Plant & Environmental New Resources, Kyung Hee University, Yongin 446-701, Korea.
| | - Hyung-Woo Jeon
- Department of Plant & Environmental New Resources, Kyung Hee University, Yongin 446-701, Korea.
- School of Life and Environmental Sciences, The University of Sydney, Camperdown, NSW 2006, Australia.
| | - Kanidta Sangsawang
- Department of Plant & Environmental New Resources, Kyung Hee University, Yongin 446-701, Korea.
| | - Donghwan Shim
- Korea Forest Research Institute, Suwon 16631, Korea.
| | - Young-Im Choi
- Korea Forest Research Institute, Suwon 16631, Korea.
| | - Eung-Jun Park
- Korea Forest Research Institute, Suwon 16631, Korea.
| | - Hyoshin Lee
- Korea Forest Research Institute, Suwon 16631, Korea.
| | - Jae-Heung Ko
- Department of Plant & Environmental New Resources, Kyung Hee University, Yongin 446-701, Korea.
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Cho J, Jeon H, Kim M, Vo TK, Kim J, Park E, Choi Y, Lee H, Han K, Ko J. Wood forming tissue-specific bicistronic expression of PdGA20ox1 and PtrMYB221 improves both the quality and quantity of woody biomass production in a hybrid poplar. PLANT BIOTECHNOLOGY JOURNAL 2019; 17:1048-1057. [PMID: 30515982 PMCID: PMC6523601 DOI: 10.1111/pbi.13036] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 09/27/2018] [Accepted: 10/28/2018] [Indexed: 05/22/2023]
Abstract
With the exponential growth of the human population and industrial developments, research on renewable energy resources is required to alleviate environmental and economic impacts caused by the consumption of fossil fuels. In this study, we present a synthetic biological application of a wood forming tissue-specific bicistronic gene expression system to improve both the quantity and quality of woody biomass to minimize undesirable growth penalties. Our transgenic poplars, designed to express both PdGA20ox1 (a GA20-oxidase from Pinus densiflora producing bioactive gibberellin, GA) and PtrMYB221 (a MYB transcription factor negatively regulating lignin biosynthesis) under the developing xylem (DX) tissue-specific promoter (i.e., DX15::PdGA20ox1-2A-PtrMYB221 poplar), resulted in a 2-fold increase in biomass quantity compared to wild-type (WT), without undesirable growth defects. A similar phenotype was observed in transgenic Arabidopsis plants harboring the same gene constructs. These phenotypic consequences were further verified in the field experiments. Importantly, our transgenic poplars exhibited an improved quality of biomass with reduced lignin content (~16.0 wt%) but increased holocellulose content (~6.6 wt%). Furthermore, the saccharification efficiency of our transgenic poplar increased significantly by up to 8%. Our results demonstrate that the controlled production of both GA and a secondary wall modifying regulator in the same spatio-temporal manner can be utilized as an efficient biotechnological tool for producing the desired multi-purpose woody biomass.
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Affiliation(s)
- Jin‐Seong Cho
- Department of Plant & Environmental New ResourcesKyung Hee UniversityYonginKorea
| | - Hyung‐Woo Jeon
- Department of Plant & Environmental New ResourcesKyung Hee UniversityYonginKorea
| | - Min‐Ha Kim
- Department of Plant & Environmental New ResourcesKyung Hee UniversityYonginKorea
| | - The K. Vo
- Department of Chemical EngineeringKyung Hee UniversityYonginKorea
| | - Jinsoo Kim
- Department of Chemical EngineeringKyung Hee UniversityYonginKorea
| | - Eung‐Jun Park
- Division of Forest BiotechnologyKorea Forest Research InstituteSuwonKorea
| | - Young‐Im Choi
- Division of Forest BiotechnologyKorea Forest Research InstituteSuwonKorea
| | - Hyoshin Lee
- Division of Forest BiotechnologyKorea Forest Research InstituteSuwonKorea
| | - Kyung‐Hwan Han
- Department of Horticulture and Department of ForestryMichigan State UniversityEast LansingMIUSA
| | - Jae‐Heung Ko
- Department of Plant & Environmental New ResourcesKyung Hee UniversityYonginKorea
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14
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Abstract
Balsam poplar (Populus balsamifera L.) is a transcontinental tree species in North America, making it an ideal species to study intra-specific hybrid vigour as a tool for increasing genetic gain in growth. We tested the hypothesis that intra-specific breeding of disparate populations of balsam poplar would lead to the expression of hybrid vigour and we determined the role of endogenous hormones linked to ecophysiological and growth performance. In September 2009, three field trials were established in Canada (two in Alberta (AB), i.e., Fields AB1 and AB2, and one in Quebec (QC), i.e., Field QC1) in conjunction with Alberta-Pacific Forest Industries Inc. and the Ministry of Forests, Wildlife and Parks, Quebec. Five male parents from each province as well as five female parents from QC and four female parents from AB were used for breeding intra-regional and inter-regional crosses. Based on a significant difference at year six for height and diameter, from the AB1 and AB2 field trials, the AB × QC cross-type was selected for further study. Cuttings from the AB × QC cross-type were grown in a randomized complete block design under near-optimal greenhouse conditions. Families were identified as slow- or fast-growing, and the relationship between hormone levels and growth performance of the genotypes within the families were examined. In late June, after 34 days of growth, internode tissue samples collected from each progeny were analyzed for gibberellic acids, indole-3-acetic acid, and abscisic acid content. Stem volume of two-month-old rooted cuttings, grown under optimal greenhouse conditions, was positively and significantly correlated with the photosynthetic rate, greenhouse growth, and stem volume of 8-year-old field-grown trees (Fields AB1 values: r = 0.629 and p = 0.012; AB2 values: r = 0.619 and p = 0.014, and QC1 values: r = 0.588 and p = 0.021, respectively). We determined that disparate and native populations of balsam poplar can be bred to produce superior progeny with enhanced stem growth traits.
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Chao Q, Gao Z, Zhang D, Zhao B, Dong F, Fu C, Liu L, Wang B. The developmental dynamics of the Populus stem transcriptome. PLANT BIOTECHNOLOGY JOURNAL 2019; 17:206-219. [PMID: 29851301 PMCID: PMC6330540 DOI: 10.1111/pbi.12958] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 05/23/2018] [Accepted: 05/27/2018] [Indexed: 05/20/2023]
Abstract
The Populus shoot undergoes primary growth (longitudinal growth) followed by secondary growth (radial growth), which produces biomass that is an important source of energy worldwide. We adopted joint PacBio Iso-Seq and RNA-seq analysis to identify differentially expressed transcripts along a developmental gradient from the shoot apex to the fifth internode of Populus Nanlin895. We obtained 87 150 full-length transcripts, including 2081 new isoforms and 62 058 new alternatively spliced isoforms, most of which were produced by intron retention, that were used to update the Populus annotation. Among these novel isoforms, there are 1187 long non-coding RNAs and 356 fusion genes. Using this annotation, we found 15 838 differentially expressed transcripts along the shoot developmental gradient, of which 1216 were transcription factors (TFs). Only a few of these genes were reported previously. The differential expression of these TFs suggests that they may play important roles in primary and secondary growth. AP2, ARF, YABBY and GRF TFs are highly expressed in the apex, whereas NAC, bZIP, PLATZ and HSF TFs are likely to be important for secondary growth. Overall, our findings provide evidence that long-read sequencing can complement short-read sequencing for cataloguing and quantifying eukaryotic transcripts and increase our understanding of the vital and dynamic process of shoot development.
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Affiliation(s)
- Qing Chao
- Key Laboratory of PhotobiologyPhotosynthesis Research CenterInstitute of BotanyChinese Academy of SciencesBeijingChina
| | - Zhi‐Fang Gao
- Key Laboratory of PhotobiologyPhotosynthesis Research CenterInstitute of BotanyChinese Academy of SciencesBeijingChina
- University of Chinese Academy of SciencesBeijingChina
| | - Dong Zhang
- Biomarker Technologies CorporationBeijingChina
| | - Biligen‐Gaowa Zhao
- Key Laboratory of PhotobiologyPhotosynthesis Research CenterInstitute of BotanyChinese Academy of SciencesBeijingChina
- University of Chinese Academy of SciencesBeijingChina
| | - Feng‐Qin Dong
- The Key Laboratory of Plant Molecular PhysiologyInstitute of BotanyChinese Academy of SciencesBeijingChina
| | - Chun‐Xiang Fu
- Key Laboratory of BiofuelsQingdao Engineering Research Center of Biomass Resources and EnvironmentQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoShandongChina
| | - Li‐Jun Liu
- College of ForestryShandong Agricultural UniversityTai‐AnShandongChina
| | - Bai‐Chen Wang
- Key Laboratory of PhotobiologyPhotosynthesis Research CenterInstitute of BotanyChinese Academy of SciencesBeijingChina
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Bdeir R, Muchero W, Yordanov Y, Tuskan GA, Busov V, Gailing O. Quantitative trait locus mapping of Populus bark features and stem diameter. BMC PLANT BIOLOGY 2017; 17:224. [PMID: 29179673 PMCID: PMC5704590 DOI: 10.1186/s12870-017-1166-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Accepted: 11/10/2017] [Indexed: 05/08/2023]
Abstract
BACKGROUND Bark plays important roles in photosynthate transport and storage, along with physical and chemical protection. Bark texture varies extensively among species, from smooth to fissured to deeply furrowed, but its genetic control is unknown. This study sought to determine the main genomic regions associated with natural variation in bark features and stem diameter. Quantitative trait loci (QTL) were mapped using an interspecific pseudo-backcross pedigree (Populus trichocarpa x P. deltoides and P. deltoides) for bark texture, bark thickness and diameter collected across three years, two sites and three biological replicates per site. RESULTS QTL specific to bark texture were highly reproducible in shared intervals across sites, years and replicates. Significant positive correlations and co-localization between trait QTL suggest pleiotropic regulators or closely linked genes. A list of candidate genes with related putative function, location close to QTL maxima and with the highest expression level in the phloem, xylem and cambium was identified. CONCLUSION Candidate genes for bark texture included an ortholog of Arabidopsis ANAC104 (PopNAC128), which plays a role in lignified fiber cell and ray development, as well as Pinin and Fasciclin (PopFLA) genes with a role in cell adhesion, cell shape and migration. The results presented in this study provide a basis for future genomic characterization of genes found within the QTL for bark texture, bark thickness and diameter in order to better understand stem and bark development in Populus and other woody perennial plants. The QTL mapping approach identified a list of prime candidate genes for further validation using functional genomics or forward genetics approaches.
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Affiliation(s)
- Roba Bdeir
- School of Forest Resources and Environmental Science, Michigan Technological University, 1400 Townsend Drive, Houghton, MI 49931 USA
| | - Wellington Muchero
- Biosciences Division, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831 USA
| | - Yordan Yordanov
- Departement of Biology, Eastern Illinois University, 600 Lincoln Ave, Charleston, IL 61920 USA
| | - Gerald A. Tuskan
- Biosciences Division, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831 USA
| | - Victor Busov
- School of Forest Resources and Environmental Science, Michigan Technological University, 1400 Townsend Drive, Houghton, MI 49931 USA
| | - Oliver Gailing
- School of Forest Resources and Environmental Science, Michigan Technological University, 1400 Townsend Drive, Houghton, MI 49931 USA
- Present address: Forest Genetics and Forest Tree Breeding, Faculty of Forest Sciences, University of Göttingen, Büsgenweg 2, 37077 Göttingen, Germany
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17
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Biotechnological Strategies to Improve Plant Biomass Quality for Bioethanol Production. BIOMED RESEARCH INTERNATIONAL 2017; 2017:7824076. [PMID: 28951875 PMCID: PMC5603102 DOI: 10.1155/2017/7824076] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 07/13/2017] [Accepted: 07/19/2017] [Indexed: 11/17/2022]
Abstract
The transition from an economy dependent on nonrenewable energy sources to one with higher diversity of renewables will not be a simple process. It requires an important research effort to adapt to the dynamics of the changing energy market, sort costly processes, and avoid overlapping with social interest markets such as food and livestock production. In this review, we analyze the desirable traits of raw plant materials for the bioethanol industry and the molecular biotechnology strategies employed to improve them, in either plants already under use (as maize) or proposed species (large grass families). The fundamentals of these applications can be found in the mechanisms by which plants have evolved different pathways to manage carbon resources for reproduction or survival in unexpected conditions. Here, we review the means by which this information can be used to manipulate these mechanisms for commercial uses, including saccharification improvement of starch and cellulose, decrease in cell wall recalcitrance through lignin modification, and increase in plant biomass.
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18
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Cho JS, Nguyen VP, Jeon HW, Kim MH, Eom SH, Lim YJ, Kim WC, Park EJ, Choi YI, Ko JH. Overexpression of PtrMYB119, a R2R3-MYB transcription factor from Populus trichocarpa, promotes anthocyanin production in hybrid poplar. TREE PHYSIOLOGY 2016; 36:1162-76. [PMID: 27259636 DOI: 10.1093/treephys/tpw046] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 04/26/2016] [Indexed: 05/12/2023]
Abstract
Anthocyanins are a group of colorful and bioactive natural pigments with important physiological and ecological functions in plants. We found an MYB transcription factor (PtrMYB119) from Populus trichocarpa that positively regulates anthocyanin production when expressed under the control of the CaMV 35S promoter in transgenic Arabidopsis Amino acid sequence analysis revealed that PtrMYB119 is highly homologous to Arabidopsis PAP1 (PRODUCTION OF ANTHOCYANIN PIGMENT1), a well-known transcriptional activator of anthocyanin biosynthesis. Independently produced transgenic poplars overexpressing PtrMYB119 or PtrMYB120 (a paralogous gene to PtrMYB119) (i.e., 35S::PtrMYB119 and 35S::PtrMYB120, respectively) showed elevated accumulation of anthocyanins in the whole plants, including leaf, stem and even root tissues. Using a reverse-phase high-performance liquid chromatography, we confirmed that the majority of the accumulated anthocyanin in our transgenic poplar is cyanidin-3-O-glucoside. Gene expression analyses revealed that most of the genes involved in the anthocyanin biosynthetic pathway were highly upregulated in 35S::PtrMYB119 poplars compared with the nontransformed control poplar. Among these genes, expression of PtrCHS1 (Chalcone Synthase1) and PtrANS2 (Anthocyanin Synthase2), which catalyze the initial and last steps of anthocyanin biosynthesis, respectively, was upregulated by up to 350-fold. Subsequent transient activation assays confirmed that PtrMYB119 activated the transcription of both PtrCHS1 and PtrANS2 Interestingly, expression of MYB182, a repressor of both anthocyanin and proanthocyanidin (PA) biosynthesis, was largely suppressed in 35S::PtrMYB119 poplars, while expression of MYB134, an activator of PA biosynthesis, was not changed significantly. More interestingly, high-level accumulation of anthocyanins in 35S::PtrMYB119 poplars did not have an adverse effect on plant growth. Taken together, our results demonstrate that PtrMYB119 and PtrMYB120 function as transcriptional activators of anthocyanin accumulation in both Arabidopsis and poplar.
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Affiliation(s)
- Jin-Seong Cho
- Department of Plant & Environmental New Resources, Kyung Hee University, Yongin 446-701, Yongin 17104, Republic of Korea Division of Forest Biotechnology, Korea Forest Research Institute, Suwon 16631, Republic of Korea
| | - Van Phap Nguyen
- Department of Plant & Environmental New Resources, Kyung Hee University, Yongin 446-701, Yongin 17104, Republic of Korea
| | - Hyung-Woo Jeon
- Department of Plant & Environmental New Resources, Kyung Hee University, Yongin 446-701, Yongin 17104, Republic of Korea
| | - Min-Ha Kim
- Department of Plant & Environmental New Resources, Kyung Hee University, Yongin 446-701, Yongin 17104, Republic of Korea
| | - Seok Hyun Eom
- Department of Horticultural Biotechnology, Kyung Hee University, Yongin 17104, Republic of Korea
| | - You Jin Lim
- Department of Horticultural Biotechnology, Kyung Hee University, Yongin 17104, Republic of Korea
| | - Won-Chan Kim
- School of Applied Biosciences, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Eung-Jun Park
- Division of Forest Biotechnology, Korea Forest Research Institute, Suwon 16631, Republic of Korea
| | - Young-Im Choi
- Division of Forest Biotechnology, Korea Forest Research Institute, Suwon 16631, Republic of Korea
| | - Jae-Heung Ko
- Department of Plant & Environmental New Resources, Kyung Hee University, Yongin 446-701, Yongin 17104, Republic of Korea
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Nguyen VP, Cho JS, Choi YI, Lee SW, Han KH, Ko JH. Evaluation of a novel promoter from Populus trichocarpa for mature xylem tissue specific gene delivery. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2016; 104:226-233. [PMID: 27038601 DOI: 10.1016/j.plaphy.2016.03.033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Revised: 03/23/2016] [Accepted: 03/26/2016] [Indexed: 06/05/2023]
Abstract
Wood (i.e., secondary xylem) is an important raw material for many industrial applications. Mature xylem (MX) tissue-specific genetic modification offers an effective means to improve the chemical and physical properties of the wood. Here, we describe a promoter that drives strong gene expression in a MX tissue-specific manner. Using whole-transcriptome genechip analyses of different tissue types of poplar, we identified five candidate genes that had strong expression in the MX tissue. The putative promoter sequences of the five MX-specific genes were evaluated for their promoter activity in both transgenic Arabidopsis and poplar. Among them, we found the promoter of Potri.013G007900.1 (called the PtrMX3 promoter) had the strongest activity in MX and thus was further characterized. In the stem and root tissues of transgenic Arabidopsis plants, the PtrMX3 promoter activity was found exclusively in MX tissue. MX-specific activity of the promoter was reproduced in the stem tissue of transgenic poplar plants. The PtrMX3 promoter activity was not influenced by abiotic stresses or exogenously applied growth regulators, indicating the PtrMX3 promoter is bona fide MX tissue-specific. Our study provides a strong MX-specific promoter for MX-specific modifications of woody biomass.
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Affiliation(s)
- Van Phap Nguyen
- Department of Plant & Environmental New Resources, Kyung Hee University, Yongin 17104, Republic of Korea
| | - Jin-Seong Cho
- Department of Plant & Environmental New Resources, Kyung Hee University, Yongin 17104, Republic of Korea; Division of Forest Biotechnology, Korea Forest Research Institute, Suwon 16631, Republic of Korea
| | - Young-Im Choi
- Division of Forest Biotechnology, Korea Forest Research Institute, Suwon 16631, Republic of Korea
| | - Sang-Won Lee
- Department of Genetic Engineering & Crop Biotech Institute, Kyung Hee University, Yongin 17104, Republic of Korea
| | - Kyung-Hwan Han
- Department of Horticulture and Department of Forestry, Michigan State University, East Lansing, MI 48824-1222, USA
| | - Jae-Heung Ko
- Department of Plant & Environmental New Resources, Kyung Hee University, Yongin 17104, Republic of Korea.
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Jeon HW, Cho JS, Park EJ, Han KH, Choi YI, Ko JH. Developing xylem-preferential expression of PdGA20ox1, a gibberellin 20-oxidase 1 from Pinus densiflora, improves woody biomass production in a hybrid poplar. PLANT BIOTECHNOLOGY JOURNAL 2016; 14:1161-70. [PMID: 26503830 DOI: 10.1111/pbi.12484] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Revised: 08/07/2015] [Accepted: 09/06/2015] [Indexed: 05/21/2023]
Abstract
Woody biomass has gained popularity as an environmentally friendly, renewable and sustainable resource for liquid fuel production. Here, we demonstrate biotechnological improvement of the quantity and quality of woody biomass by employing developing xylem (DX)-preferential production of gibberellin (GA), a phytohormone that positively regulates stem growth. First, for the proof of concept experiment, we produced transgenic Arabidopsis plants expressing GA20-oxidase, a key enzyme in the production of bioactive GAs, from Pinus densiflora (PdGA20ox1) under the control of either a constitutive 35S promoter, designated 35S::PdGA20ox1, or a DX-specific promoter (originated from poplar), designated DX15::PdGA20ox1. As we hypothesized, both transgenic Arabidopsis plants (35S::PdGA20ox1 and DX15::PdGA20ox1) exhibited an accelerated stem growth that resulted in a large increase of biomass, up to 300% compared to wild-type control plants, together with increased secondary wall thickening and elongation of fibre cells. Next, we applied our concept to the production of transgenic poplar trees. Both transgenic poplar trees (35S::PdGA20ox1 and DX15::PdGA20ox1) showed dramatic increases in biomass, up to 300%, with accelerated stem growth and xylem differentiation. Cell wall monosaccharide composition analysis revealed that in both Arabidopsis and poplar, glucose and xylose contents were significantly increased. However, undesirable phenotypes of 35S::PdGA20ox1 poplar, including poor root growth and leaf development, were found. Interestingly, DX15::PdGA20ox1 poplar resulted in a reduction of undesirable phenotypes. Our results indicate that the controlled production of GAs through a tissue-specific promoter can be utilized as an efficient biotechnological tool for producing enhanced plant biomass, minimizing unwanted effects.
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Affiliation(s)
- Hyung-Woo Jeon
- Department of Plant & Environmental New Resources, Kyung Hee University, Yongin, Korea
| | - Jin-Seong Cho
- Department of Plant & Environmental New Resources, Kyung Hee University, Yongin, Korea
- Division of Forest Biotechnology, Korea Forest Research Institute, Suwon, Korea
| | - Eung-Jun Park
- Division of Forest Biotechnology, Korea Forest Research Institute, Suwon, Korea
| | - Kyung-Hwan Han
- Department of Horticulture and Department of Forestry, Michigan State University, East Lansing, MI, USA
| | - Young-Im Choi
- Division of Forest Biotechnology, Korea Forest Research Institute, Suwon, Korea
| | - Jae-Heung Ko
- Department of Plant & Environmental New Resources, Kyung Hee University, Yongin, Korea
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21
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Terol J, Tadeo F, Ventimilla D, Talon M. An RNA-Seq-based reference transcriptome for Citrus. PLANT BIOTECHNOLOGY JOURNAL 2016; 14:938-50. [PMID: 26261026 DOI: 10.1111/pbi.12447] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Revised: 06/04/2015] [Accepted: 07/01/2015] [Indexed: 05/20/2023]
Abstract
Previous RNA-Seq studies in citrus have been focused on physiological processes relevant to fruit quality and productivity of the major species, especially sweet orange. Less attention has been paid to vegetative or reproductive tissues, while most Citrus species have never been analysed. In this work, we characterized the transcriptome of vegetative and reproductive tissues from 12 Citrus species from all main phylogenetic groups. Our aims were to acquire a complete view of the citrus transcriptome landscape, to improve previous functional annotations and to obtain genetic markers associated with genes of agronomic interest. 28 samples were used for RNA-Seq analysis, obtained from 12 Citrus species: C. medica, C. aurantifolia, C. limon, C. bergamia, C. clementina, C. deliciosa, C. reshni, C. maxima, C. paradisi, C. aurantium, C. sinensis and Poncirus trifoliata. Four different organs were analysed: root, phloem, leaf and flower. A total of 3421 million Illumina reads were produced and mapped against the reference C. clementina genome sequence. Transcript discovery pipeline revealed 3326 new genes, the number of genes with alternative splicing was increased to 19,739, and a total of 73,797 transcripts were identified. Differential expression studies between the four tissues showed that gene expression is overall related to the physiological function of the specific organs above any other variable. Variants discovery analysis revealed the presence of indels and SNPs in genes associated with fruit quality and productivity. Pivotal pathways in citrus such as those of flavonoids, flavonols, ethylene and auxin were also analysed in detail.
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Affiliation(s)
- Javier Terol
- Centro de Genómica, Instituto Valenciano de Investigaciones Agrarias (IVIA), Moncada, Valencia, Spain
| | - Francisco Tadeo
- Centro de Genómica, Instituto Valenciano de Investigaciones Agrarias (IVIA), Moncada, Valencia, Spain
| | - Daniel Ventimilla
- Centro de Genómica, Instituto Valenciano de Investigaciones Agrarias (IVIA), Moncada, Valencia, Spain
| | - Manuel Talon
- Centro de Genómica, Instituto Valenciano de Investigaciones Agrarias (IVIA), Moncada, Valencia, Spain
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Paul S, Wildhagen H, Janz D, Teichmann T, Hänsch R, Polle A. Tissue- and Cell-Specific Cytokinin Activity in Populus × canescens Monitored by ARR5::GUS Reporter Lines in Summer and Winter. FRONTIERS IN PLANT SCIENCE 2016; 7:652. [PMID: 27242853 PMCID: PMC4865519 DOI: 10.3389/fpls.2016.00652] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 04/28/2016] [Indexed: 05/20/2023]
Abstract
Cytokinins play an important role in vascular development. But knowledge on the cellular localization of this growth hormone in the stem and other organs of woody plants is lacking. The main focus of this study was to investigate the occurrence and cellular localization of active cytokinins in leaves, roots, and along the stem of Populus × canescens and to find out how the pattern is changed between summer and winter. An ARR5::GUS reporter construct was used to monitor distribution of active cytokinins in different tissues of transgenic poplar lines. Three transgenic lines tested under outdoor conditions showed no influence of ARR5::GUS reporter construct on the growth performance compared with the wild-type, but one line lost the reporter activity. ARR5::GUS activity indicated changes in the tissue- and cell type-specific pattern of cytokinin activity during dormancy compared with the growth phase. ARR5::GUS activity, which was present in the root tips in the growing season, disappeared in winter. In the stem apex ground tissue, ARR5::GUS activity was higher in winter than in summer. Immature leaves from tissue-culture grown plants showed inducible ARR5::GUS activity. Leaf primordia in summer showed ARR5::GUS activity, but not the expanded leaves of outdoor plants or leaf primordia in winter. In stem cross sections, the most prominent ARR5::GUS activity was detected in the cortex region and in the rays of bark in summer and in winter. In the cambial zone the ARR5::GUS activity was more pronounced in the dormant than in growth phase. The pith and the ray cells adjacent to the vessels also displayed ARR5::GUS activity. In silico analyses of the tissue-specific expression patterns of the whole PtRR type-A family of poplar showed that PtRR10, the closest ortholog to the Arabidopsis ARR5 gene, was usually the most highly expressed gene in all tissues. In conclusion, gene expression and tissue-localization indicate high activity of cytokinins not only in summer, but also in winter. The presence of the signal in meristematic tissues supports their role in meristem maintenance. The reporter lines will be useful to study the involvement of cytokinins in acclimation of poplar growth to stress.
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Affiliation(s)
- Shanty Paul
- Department of Forest Botany and Tree Physiology, Georg-August-Universität GöttingenGöttingen, Germany
| | - Henning Wildhagen
- Department of Forest Botany and Tree Physiology, Georg-August-Universität GöttingenGöttingen, Germany
| | - Dennis Janz
- Department of Forest Botany and Tree Physiology, Georg-August-Universität GöttingenGöttingen, Germany
| | - Thomas Teichmann
- Department of Forest Botany and Tree Physiology, Georg-August-Universität GöttingenGöttingen, Germany
| | - Robert Hänsch
- Department of Molecular and Cell Biology of Plants, Institute for Plant Biology, University of TechnologyBraunschweig, Germany
| | - Andrea Polle
- Department of Forest Botany and Tree Physiology, Georg-August-Universität GöttingenGöttingen, Germany
- *Correspondence: Andrea Polle,
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Gonzalez E, Brereton NJB, Marleau J, Guidi Nissim W, Labrecque M, Pitre FE, Joly S. Meta-transcriptomics indicates biotic cross-tolerance in willow trees cultivated on petroleum hydrocarbon contaminated soil. BMC PLANT BIOLOGY 2015; 15:246. [PMID: 26459343 PMCID: PMC4603587 DOI: 10.1186/s12870-015-0636-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Accepted: 09/30/2015] [Indexed: 05/09/2023]
Abstract
BACKGROUND High concentrations of petroleum hydrocarbon (PHC) pollution can be hazardous to human health and leave soils incapable of supporting agricultural crops. A cheap solution, which can help restore biodiversity and bring land back to productivity, is cultivation of high biomass yielding willow trees. However, the genetic mechanisms which allow these fast-growing trees to tolerate PHCs are as yet unclear. METHODS Salix purpurea 'Fish Creek' trees were pot-grown in soil from a former petroleum refinery, either lacking or enriched with C10-C50 PHCs. De novo assembled transcriptomes were compared between tree organs and impartially annotated without a priori constraint to any organism. RESULTS Over 45% of differentially expressed genes originated from foreign organisms, the majority from the two-spotted spidermite, Tetranychus urticae. Over 99% of T. urticae transcripts were differentially expressed with greater abundance in non-contaminated trees. Plant transcripts involved in the polypropanoid pathway, including phenylalanine ammonia-lyase (PAL), had greater expression in contaminated trees whereas most resistance genes showed higher expression in non-contaminated trees. CONCLUSIONS The impartial approach to annotation of the de novo transcriptomes, allowing for the possibility for multiple species identification, was essential for interpretation of the crop's response treatment. The meta-transcriptomic pattern of expression suggests a cross-tolerance mechanism whereby abiotic stress resistance systems provide improved biotic resistance. These findings highlight a valuable but complex biotic and abiotic stress response to real-world, multidimensional contamination which could, in part, help explain why crops such as willow can produce uniquely high biomass yields on challenging marginal land.
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Affiliation(s)
- Emmanuel Gonzalez
- Institut de recherche en biologie végétale, University of Montreal, 4101 Sherbrooke E, Montreal, QC, H1X 2B2, Canada.
| | - Nicholas J B Brereton
- Institut de recherche en biologie végétale, University of Montreal, 4101 Sherbrooke E, Montreal, QC, H1X 2B2, Canada.
| | - Julie Marleau
- Institut de recherche en biologie végétale, University of Montreal, 4101 Sherbrooke E, Montreal, QC, H1X 2B2, Canada.
| | | | - Michel Labrecque
- Institut de recherche en biologie végétale, University of Montreal, 4101 Sherbrooke E, Montreal, QC, H1X 2B2, Canada.
- Montreal Botanical Gardens, 4101 Sherbrooke E, Montreal, QC, H1X 2B2, Canada.
| | - Frederic E Pitre
- Institut de recherche en biologie végétale, University of Montreal, 4101 Sherbrooke E, Montreal, QC, H1X 2B2, Canada.
- Montreal Botanical Gardens, 4101 Sherbrooke E, Montreal, QC, H1X 2B2, Canada.
| | - Simon Joly
- Institut de recherche en biologie végétale, University of Montreal, 4101 Sherbrooke E, Montreal, QC, H1X 2B2, Canada.
- Montreal Botanical Gardens, 4101 Sherbrooke E, Montreal, QC, H1X 2B2, Canada.
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24
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Engineering Plant Biomass Lignin Content and Composition for Biofuels and Bioproducts. ENERGIES 2015. [DOI: 10.3390/en8087654] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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25
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Hefer CA, Mizrachi E, Myburg AA, Douglas CJ, Mansfield SD. Comparative interrogation of the developing xylem transcriptomes of two wood-forming species: Populus trichocarpa and Eucalyptus grandis. THE NEW PHYTOLOGIST 2015; 206:1391-405. [PMID: 25659405 DOI: 10.1111/nph.13277] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Accepted: 12/04/2014] [Indexed: 05/15/2023]
Abstract
Wood formation is a complex developmental process governed by genetic and environmental stimuli. Populus and Eucalyptus are fast-growing, high-yielding tree genera that represent ecologically and economically important species suitable for generating significant lignocellulosic biomass. Comparative analysis of the developing xylem and leaf transcriptomes of Populus trichocarpa and Eucalyptus grandis together with phylogenetic analyses identified clusters of homologous genes preferentially expressed during xylem formation in both species. A conserved set of 336 single gene pairs showed highly similar xylem preferential expression patterns, as well as evidence of high functional constraint. Individual members of multi-gene orthologous clusters known to be involved in secondary cell wall biosynthesis also showed conserved xylem expression profiles. However, species-specific expression as well as opposite (xylem versus leaf) expression patterns observed for a subset of genes suggest subtle differences in the transcriptional regulation important for xylem development in each species. Using sequence similarity and gene expression status, we identified functional homologs likely to be involved in xylem developmental and biosynthetic processes in Populus and Eucalyptus. Our study suggests that, while genes involved in secondary cell wall biosynthesis show high levels of gene expression conservation, differential regulation of some xylem development genes may give rise to unique xylem properties.
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Affiliation(s)
- Charles A Hefer
- Department of Botany, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Eshchar Mizrachi
- Department of Genetics, Forestry and Agricultural Biotechnology Institute (FABI), Genomics Research Institute (GRI), University of Pretoria, Private bag X20, Pretoria, 0028, South Africa
| | - Alexander A Myburg
- Department of Genetics, Forestry and Agricultural Biotechnology Institute (FABI), Genomics Research Institute (GRI), University of Pretoria, Private bag X20, Pretoria, 0028, South Africa
| | - Carl J Douglas
- Department of Botany, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Shawn D Mansfield
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Forest Sciences Centre, 4030-2424 Main Mall, Vancouver, BC, V6T 1Z4, Canada
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Tian F, Wang T, Xie Y, Zhang J, Hu J. Genome-wide identification, classification, and expression analysis of 14-3-3 gene family in Populus. PLoS One 2015; 10:e0123225. [PMID: 25867623 PMCID: PMC4395111 DOI: 10.1371/journal.pone.0123225] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2014] [Accepted: 02/17/2015] [Indexed: 11/18/2022] Open
Abstract
Background In plants, 14-3-3 proteins are encoded by a large multigene family and are involved in signaling pathways to regulate plant development and protection from stress. Although twelve Populus 14-3-3s were identified based on the Populus trichocarpa genome V1.1 in a previous study, no systematic analysis including genome organization, gene structure, duplication relationship, evolutionary analysis and expression compendium has been conducted in Populus based on the latest P. trichocarpa genome V3.0. Principal Findings Here, a comprehensive analysis of Populus 14-3-3 family is presented. Two new 14-3-3 genes were identified based on the latest P. trichocarpa genome. In P. trichocarpa, fourteen 14-3-3 genes were grouped into ε and non-ε group. Exon-intron organizations of Populus 14-3-3s are highly conserved within the same group. Genomic organization analysis indicated that purifying selection plays a pivotal role in the retention and maintenance of Populus 14-3-3 family. Protein conformational analysis indicated that Populus 14-3-3 consists of a bundle of nine α-helices (α1-α9); the first four are essential for formation of the dimer, while α3, α5, α7, and α9 form a conserved peptide-binding groove. In addition, α1, α3, α5, α7, and α9 were evolving at a lower rate, while α2, α4, and α6 were evolving at a relatively faster rate. Microarray analyses showed that most Populus 14-3-3s are differentially expressed across tissues and upon exposure to various stresses. Conclusions The gene structures and their coding protein structures of Populus 14-3-3s are highly conserved among group members, suggesting that members of the same group might also have conserved functions. Microarray and qRT-PCR analyses showed that most Populus 14-3-3s were differentially expressed in various tissues and were induced by various stresses. Our investigation provided a better understanding of the complexity of the 14-3-3 gene family in poplars.
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Affiliation(s)
- Fengxia Tian
- College of Life Science and Technology, Nanyang Normal University, 1638 Wolong Road, Nanyang, Henan, China
- State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of the State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, China
| | - Tan Wang
- College of Life Science and Technology, Nanyang Normal University, 1638 Wolong Road, Nanyang, Henan, China
- State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of the State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, China
| | - Yuli Xie
- College of Life Science and Technology, Nanyang Normal University, 1638 Wolong Road, Nanyang, Henan, China
- State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of the State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, China
| | - Jin Zhang
- State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of the State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, China
- * E-mail: (JZ); (JH)
| | - Jianjun Hu
- State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of the State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, China
- * E-mail: (JZ); (JH)
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27
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Ratke C, Pawar PMA, Balasubramanian VK, Naumann M, Duncranz ML, Derba-Maceluch M, Gorzsás A, Endo S, Ezcurra I, Mellerowicz EJ. Populus GT43 family members group into distinct sets required for primary and secondary wall xylan biosynthesis and include useful promoters for wood modification. PLANT BIOTECHNOLOGY JOURNAL 2015; 13:26-37. [PMID: 25100045 DOI: 10.1111/pbi.12232] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Revised: 06/24/2014] [Accepted: 06/29/2014] [Indexed: 05/05/2023]
Abstract
The plant GT43 protein family includes xylosyltransferases that are known to be required for xylan backbone biosynthesis, but have incompletely understood specificities. RT-qPCR and histochemical (GUS) analyses of expression patterns of GT43 members in hybrid aspen, reported here, revealed that three clades of the family have markedly differing specificity towards secondary wall-forming cells (wood and extraxylary fibres). Intriguingly, GT43A and B genes (corresponding to the Arabidopsis IRX9 clade) showed higher specificity for secondary-walled cells than GT43C and D genes (IRX14 clade), although both IRX9 and IRX14 are required for xylosyltransferase activity. The remaining genes, GT43E, F and G (IRX9-L clade), showed broad expression patterns. Transient transactivation analyses of GT43A and B reporters demonstrated that they are activated by PtxtMYB021 and PNAC085 (master secondary wall switches), mediated in PtxtMYB021 activation by an AC element. The high observed secondary cell wall specificity of GT43B expression prompted tests of the efficiency of its promoter (pGT43B), relative to the CaMV 35S (35S) promoter, for overexpressing a xylan acetyl esterase (CE5) or downregulating REDUCED WALL ACETYLATION (RWA) family genes and thus engineering wood acetylation. CE5 expression was weaker when driven by pGT43B, but it reduced wood acetyl content substantially more efficiently than the 35S promoter. RNAi silencing of the RWA family, which was ineffective using 35S, was achieved when using GT43B promoter. These results show the utility of the GT43B promoter for genetically engineering properties of wood and fibres.
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Affiliation(s)
- Christine Ratke
- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences (SLU), Umeå, Sweden
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28
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Kim WC, Kim JY, Ko JH, Kang H, Kim J, Han KH. AtC3H14, a plant-specific tandem CCCH zinc-finger protein, binds to its target mRNAs in a sequence-specific manner and affects cell elongation in Arabidopsis thaliana. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2014; 80:772-84. [PMID: 25228083 DOI: 10.1111/tpj.12667] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2014] [Revised: 08/27/2014] [Accepted: 08/29/2014] [Indexed: 05/19/2023]
Abstract
AtC3H14 (At1 g66810) is a plant-specific tandem CCCH zinc-finger (TZF) protein that belongs to the 68-member CCCH family in Arabidopsis thaliana. In animals, TZFs have been shown to bind and recruit target mRNAs to the cytoplasmic foci where mRNA decay enzymes are active. However, it is not known whether plant TZF proteins such as AtC3H14 function. So far, no mRNA targets of plant TZFs have been identified. We have obtained several lines of experimental evidence in support of our hypothesis that AtC3H14 is involved in post-transcriptional regulation of its target genes. Nucleic acid binding assays using [(35) S]-labeled AtC3H14 protein showed that AtC3H14 could bind to ssDNA, dsDNA, and ribohomopolymers, suggesting its RNA-binding activity. RNA immunoprecipitation (RIP) assay identified several putative target RNAs of AtC3H14, including a polygalacturonase, a well-known cell wall modifying gene. RNA electrophoretic mobility shift assays (RNA-EMSA) were used to confirm the RIP results and demonstrate that the TZF domain of AtC3H14 is required for the target RNA binding. Microarray analysis of 35S::AtC3H14 plants revealed that many of the cell wall elongation and/or modification-associated genes were differentially expressed, which is consistent with the cell elongation defect phenotype and the changes in the cell wall monosaccharide composition. In addition, yeast activation assay showed that AtC3H14 also function as a transcriptional activator, which is consistent with the previous finding that AtC3H14 activate the secondary wall biosynthesis genes. Taken together, we conclude that AtC3H14 may play a key role in both transcriptional and post-transcriptional regulation.
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Affiliation(s)
- Won-Chan Kim
- Department of Horticulture and Department of Forestry, Michigan State University, East Lansing, MI, 48824-1222, USA; DOE-Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI, 48824-1222, USA
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29
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Xu P, Kong Y, Song D, Huang C, Li X, Li L. Conservation and functional influence of alternative splicing in wood formation of Populus and Eucalyptus. BMC Genomics 2014; 15:780. [PMID: 25209012 PMCID: PMC4287496 DOI: 10.1186/1471-2164-15-780] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2014] [Accepted: 09/08/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Wood formation in tree species is regulated by multiple factors at various layers. Alternative splicing (AS) occurs within a large number of genes in wood formation. However, the functional implications and conservation of the AS occurrence are not well understood. RESULTS In this study, we profiled AS events in wood-forming tissues of Populus and Eucalyptus, and analyzed their functional implications as well as inter-species conservation. 28.3% and 20.7% of highly expressed transcripts in the developing xylem of Populus and Eucalyptus respectively were affected by AS events. Around 42% of the AS events resulted in changes to the original reading frame. 25.0% (in Populus) and 26.8% (in Eucalyptus) of the AS events may cause protein domain modification. In the process of wood formation, about 28% of AS-occurring genes were putative orthologs and 71 conserved AS events were identified in the two species. CONCLUSION Through analysis of AS events in developing xylem of two tree species, this study reveals an array of new information regarding AS occurrence and function in tree development.
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Affiliation(s)
| | | | | | | | | | - Laigeng Li
- National Key Laboratory of Plant Molecular Genetics and Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, 300 Fenglin Rd, Shanghai, 200032, China.
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30
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Mewalal R, Mizrachi E, Mansfield SD, Myburg AA. Cell wall-related proteins of unknown function: missing links in plant cell wall development. PLANT & CELL PHYSIOLOGY 2014; 55:1031-43. [PMID: 24683037 DOI: 10.1093/pcp/pcu050] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Lignocellulosic biomass is an important feedstock for the pulp and paper industry as well as emerging biofuel and biomaterial industries. However, the recalcitrance of the secondary cell wall to chemical or enzymatic degradation remains a major hurdle for efficient extraction of economically important biopolymers such as cellulose. It has been estimated that approximately 10-15% of about 27,000 protein-coding genes in the Arabidopsis genome are dedicated to cell wall development; however, only about 130 Arabidopsis genes thus far have experimental evidence validating cell wall function. While many genes have been implicated through co-expression analysis with known genes, a large number are broadly classified as proteins of unknown function (PUFs). Recently the functionality of some of these unknown proteins in cell wall development has been revealed using reverse genetic approaches. Given the large number of cell wall-related PUFs, how do we approach and subsequently prioritize the investigation of such unknown genes that may be essential to or influence plant cell wall development and structure? Here, we address the aforementioned question in two parts; we first identify the different kinds of PUFs based on known and predicted features such as protein domains. Knowledge of inherent features of PUFs may allow for functional inference and a concomitant link to biological context. Secondly, we discuss omics-based technologies and approaches that are helping identify and prioritize cell wall-related PUFs by functional association. In this way, hypothesis-driven experiments can be designed for functional elucidation of many proteins that remain missing links in our understanding of plant cell wall biosynthesis.
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Affiliation(s)
- Ritesh Mewalal
- Department of Genetics, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Private bag X20, Hatfield, Pretoria, 0028, South Africa
| | - Eshchar Mizrachi
- Department of Genetics, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Private bag X20, Hatfield, Pretoria, 0028, South Africa
| | - Shawn D Mansfield
- Department of Wood Science, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Alexander A Myburg
- Department of Genetics, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Private bag X20, Hatfield, Pretoria, 0028, South Africa
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31
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Lignin bioengineering. Curr Opin Biotechnol 2014; 26:189-98. [DOI: 10.1016/j.copbio.2014.01.002] [Citation(s) in RCA: 109] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Revised: 12/24/2013] [Accepted: 01/06/2014] [Indexed: 01/08/2023]
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32
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Porth I, Klapšte J, Skyba O, Hannemann J, McKown AD, Guy RD, DiFazio SP, Muchero W, Ranjan P, Tuskan GA, Friedmann MC, Ehlting J, Cronk QCB, El-Kassaby YA, Douglas CJ, Mansfield SD. Genome-wide association mapping for wood characteristics in Populus identifies an array of candidate single nucleotide polymorphisms. THE NEW PHYTOLOGIST 2013; 200:710-726. [PMID: 23889164 DOI: 10.1111/nph.12422] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2013] [Accepted: 06/18/2013] [Indexed: 05/02/2023]
Abstract
Establishing links between phenotypes and molecular variants is of central importance to accelerate genetic improvement of economically important plant species. Our work represents the first genome-wide association study to the inherently complex and currently poorly understood genetic architecture of industrially relevant wood traits. Here, we employed an Illumina Infinium 34K single nucleotide polymorphism (SNP) genotyping array that generated 29,233 high-quality SNPs in c. 3500 broad-based candidate genes within a population of 334 unrelated Populus trichocarpa individuals to establish genome-wide associations. The analysis revealed 141 significant SNPs (α ≤ 0.05) associated with 16 wood chemistry/ultrastructure traits, individually explaining 3-7% of the phenotypic variance. A large set of associations (41% of all hits) occurred in candidate genes preselected for their suggested a priori involvement with secondary growth. For example, an allelic variant in the FRA8 ortholog explained 21% of the total genetic variance in fiber length, when the trait's heritability estimate was considered. The remaining associations identified SNPs in genes not previously implicated in wood or secondary wall formation. Our findings provide unique insights into wood trait architecture and support efforts for population improvement based on desirable allelic variants.
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Affiliation(s)
- Ilga Porth
- Department of Wood Science, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
| | - Jaroslav Klapšte
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
- Department of Dendrology and Forest Tree Breeding, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences, Prague, 165 21, Czech Republic
| | - Oleksandr Skyba
- Department of Wood Science, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
| | - Jan Hannemann
- Department of Biology and Centre for Forest Biology, University of Victoria, Victoria, BC, Canada, V8W 3N5
| | - Athena D McKown
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
| | - Robert D Guy
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
| | - Stephen P DiFazio
- Department of Biology, West Virginia University, Morgantown, WV, 26506-6057, USA
| | - Wellington Muchero
- BioSciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Priya Ranjan
- BioSciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Gerald A Tuskan
- BioSciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Michael C Friedmann
- Department of Botany, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
| | - Juergen Ehlting
- Department of Biology and Centre for Forest Biology, University of Victoria, Victoria, BC, Canada, V8W 3N5
| | - Quentin C B Cronk
- Department of Botany, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
| | - Yousry A El-Kassaby
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
| | - Carl J Douglas
- Department of Botany, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
| | - Shawn D Mansfield
- Department of Wood Science, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
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Yang F, Mitra P, Zhang L, Prak L, Verhertbruggen Y, Kim JS, Sun L, Zheng K, Tang K, Auer M, Scheller HV, Loqué D. Engineering secondary cell wall deposition in plants. PLANT BIOTECHNOLOGY JOURNAL 2013; 11:325-35. [PMID: 23140549 PMCID: PMC3644865 DOI: 10.1111/pbi.12016] [Citation(s) in RCA: 131] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Revised: 09/21/2012] [Accepted: 09/25/2012] [Indexed: 05/17/2023]
Abstract
Lignocellulosic biomass was used for thousands of years as animal feed and is now considered a great sugar source for biofuels production. It is composed mostly of secondary cell walls built with polysaccharide polymers that are embedded in lignin to reinforce the cell wall structure and maintain its integrity. Lignin is the primary material responsible for biomass recalcitrance to enzymatic hydrolysis. During plant development, deep reductions of lignin cause growth defects and often correlate with the loss of vessel integrity that adversely affects water and nutrient transport in plants. The work presented here describes a new approach to decrease lignin content while preventing vessel collapse and introduces a new strategy to boost transcription factor expression in native tissues. We used synthetic biology tools in Arabidopsis to rewire the secondary cell network by changing promoter-coding sequence associations. The result was a reduction in lignin and an increase in polysaccharide depositions in fibre cells. The promoter of a key lignin gene, C4H, was replaced by the vessel-specific promoter of transcription factor VND6. This rewired lignin biosynthesis specifically for vessel formation while disconnecting C4H expression from the fibre regulatory network. Secondly, the promoter of the IRX8 gene, secondary cell wall glycosyltransferase, was used to express a new copy of the fibre transcription factor NST1, and as the IRX8 promoter is induced by NST1, this also created an artificial positive feedback loop (APFL). The combination of strategies-lignin rewiring with APFL insertion-enhances polysaccharide deposition in stems without over-lignifying them, resulting in higher sugar yields after enzymatic hydrolysis.
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Affiliation(s)
- Fan Yang
- Joint BioEnergy Institute, Physical Biosciences Division, Lawrence Berkeley National LaboratoryOne Cyclotron Road, Berkeley, CA, USA
| | - Prajakta Mitra
- Joint BioEnergy Institute, Physical Biosciences Division, Lawrence Berkeley National LaboratoryOne Cyclotron Road, Berkeley, CA, USA
| | - Ling Zhang
- Joint BioEnergy Institute, Physical Biosciences Division, Lawrence Berkeley National LaboratoryOne Cyclotron Road, Berkeley, CA, USA
- FSN Plant Biotechnology R&D Centre, Shanghai Jiaotong UniversityShanghai, China
| | - Lina Prak
- Joint BioEnergy Institute, Physical Biosciences Division, Lawrence Berkeley National LaboratoryOne Cyclotron Road, Berkeley, CA, USA
| | - Yves Verhertbruggen
- Joint BioEnergy Institute, Physical Biosciences Division, Lawrence Berkeley National LaboratoryOne Cyclotron Road, Berkeley, CA, USA
| | - Jin-Sun Kim
- Joint BioEnergy Institute, Physical Biosciences Division, Lawrence Berkeley National LaboratoryOne Cyclotron Road, Berkeley, CA, USA
| | - Lan Sun
- Joint BioEnergy Institute, Physical Biosciences Division, Lawrence Berkeley National LaboratoryOne Cyclotron Road, Berkeley, CA, USA
| | - Kejian Zheng
- Joint BioEnergy Institute, Physical Biosciences Division, Lawrence Berkeley National LaboratoryOne Cyclotron Road, Berkeley, CA, USA
| | - Kexuan Tang
- FSN Plant Biotechnology R&D Centre, Shanghai Jiaotong UniversityShanghai, China
| | - Manfred Auer
- Joint BioEnergy Institute, Physical Biosciences Division, Lawrence Berkeley National LaboratoryOne Cyclotron Road, Berkeley, CA, USA
| | - Henrik V Scheller
- Joint BioEnergy Institute, Physical Biosciences Division, Lawrence Berkeley National LaboratoryOne Cyclotron Road, Berkeley, CA, USA
| | - Dominique Loqué
- Joint BioEnergy Institute, Physical Biosciences Division, Lawrence Berkeley National LaboratoryOne Cyclotron Road, Berkeley, CA, USA
- *Correspondence (fax 510 486 4252; email )
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Creux NM, Bossinger G, Myburg AA, Spokevicius AV. Induced somatic sector analysis of cellulose synthase (CesA) promoter regions in woody stem tissues. PLANTA 2013; 237:799-812. [PMID: 23132521 DOI: 10.1007/s00425-012-1792-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Accepted: 10/17/2012] [Indexed: 05/20/2023]
Abstract
The increasing focus on plantation forestry as a renewable source of cellulosic biomass has emphasized the need for tools to study the unique biology of woody genera such as Eucalyptus, Populus and Pinus. The domestication of these woody crops is hampered by long generation times, and breeders are now looking to molecular approaches such as marker-assisted breeding and genetic modification to accelerate tree improvement. Much of what is known about genes involved in the growth and development of plants has come from studies of herbaceous models such as Arabidopsis and rice. However, transferring this information to woody plants often proves difficult, especially for genes expressed in woody stems. Here we report the use of induced somatic sector analysis (ISSA) for characterization of promoter expression patterns directly in the stems of Populus and Eucalyptus trees. As a case study, we used previously characterized primary and secondary cell wall-related cellulose synthase (CesA) promoters cloned from Eucalyptus grandis. We show that ISSA can be used to elucidate the phloem and xylem expression patterns of the CesA genes in Eucalyptus and Populus stems and also show that the staining patterns differ in Eucalyptus and Populus stems. These findings show that ISSA is an efficient approach to investigate promoter function in the developmental context of woody plant tissues and raise questions about the suitability of heterologous promoters for genetic manipulation in plant species.
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Affiliation(s)
- Nicky M Creux
- Department of Genetics, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Private Bag X20, Pretoria, 0028, South Africa
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Petersen PD, Lau J, Ebert B, Yang F, Verhertbruggen Y, Kim JS, Varanasi P, Suttangkakul A, Auer M, Loqué D, Scheller HV. Engineering of plants with improved properties as biofuels feedstocks by vessel-specific complementation of xylan biosynthesis mutants. BIOTECHNOLOGY FOR BIOFUELS 2012; 5. [PMID: 23181474 PMCID: PMC3537538 DOI: 10.1186/1754-6834-5-84] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
BACKGROUND Cost-efficient generation of second-generation biofuels requires plant biomass that can easily be degraded into sugars and further fermented into fuels. However, lignocellulosic biomass is inherently recalcitrant toward deconstruction technologies due to the abundant lignin and cross-linked hemicelluloses. Furthermore, lignocellulosic biomass has a high content of pentoses, which are more difficult to ferment into fuels than hexoses. Engineered plants with decreased amounts of xylan in their secondary walls have the potential to render plant biomass a more desirable feedstock for biofuel production. RESULTS Xylan is the major non-cellulosic polysaccharide in secondary cell walls, and the xylan deficient irregular xylem (irx) mutants irx7, irx8 and irx9 exhibit severe dwarf growth phenotypes. The main reason for the growth phenotype appears to be xylem vessel collapse and the resulting impaired transport of water and nutrients. We developed a xylan-engineering approach to reintroduce xylan biosynthesis specifically into the xylem vessels in the Arabidopsis irx7, irx8 and irx9 mutant backgrounds by driving the expression of the respective glycosyltransferases with the vessel-specific promoters of the VND6 and VND7 transcription factor genes. The growth phenotype, stem breaking strength, and irx morphology was recovered to varying degrees. Some of the plants even exhibited increased stem strength compared to the wild type. We obtained Arabidopsis plants with up to 23% reduction in xylose levels and 18% reduction in lignin content compared to wild-type plants, while exhibiting wild-type growth patterns and morphology, as well as normal xylem vessels. These plants showed a 42% increase in saccharification yield after hot water pretreatment. The VND7 promoter yielded a more complete complementation of the irx phenotype than the VND6 promoter. CONCLUSIONS Spatial and temporal deposition of xylan in the secondary cell wall of Arabidopsis can be manipulated by using the promoter regions of vessel-specific genes to express xylan biosynthetic genes. The expression of xylan specifically in the xylem vessels is sufficient to complement the irx phenotype of xylan deficient mutants, while maintaining low overall amounts of xylan and lignin in the cell wall. This engineering approach has the potential to yield bioenergy crop plants that are more easily deconstructed and fermented into biofuels.
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Affiliation(s)
- Pia Damm Petersen
- Feedstocks Division, Joint Bioenergy Institute, 5885 Hollis St, Emeryville, CA, 94608, USA
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA, 94720, USA
- Department of Plant Biology and Biotechnology, University of Copenhagen, 40 Thorvaldsensvej, Frederiksberg C, DK-1871, Denmark
| | - Jane Lau
- Feedstocks Division, Joint Bioenergy Institute, 5885 Hollis St, Emeryville, CA, 94608, USA
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA, 94720, USA
| | - Berit Ebert
- Feedstocks Division, Joint Bioenergy Institute, 5885 Hollis St, Emeryville, CA, 94608, USA
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA, 94720, USA
| | - Fan Yang
- Feedstocks Division, Joint Bioenergy Institute, 5885 Hollis St, Emeryville, CA, 94608, USA
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA, 94720, USA
| | - Yves Verhertbruggen
- Feedstocks Division, Joint Bioenergy Institute, 5885 Hollis St, Emeryville, CA, 94608, USA
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA, 94720, USA
| | - Jin Sun Kim
- Feedstocks Division, Joint Bioenergy Institute, 5885 Hollis St, Emeryville, CA, 94608, USA
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA, 94720, USA
| | - Patanjali Varanasi
- Technology Division, Joint Bioenergy Institute, 5885 Hollis St, Emeryville, CA, 94608, USA
- Sandia National Laboratories, 7011 East Avenue, Livermore, CA, 94550, USA
| | - Anongpat Suttangkakul
- Feedstocks Division, Joint Bioenergy Institute, 5885 Hollis St, Emeryville, CA, 94608, USA
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA, 94720, USA
- Department of Genetics, Faculty of Science, Kasetsart University, Bangkok, 10900, Thailand
| | - Manfred Auer
- Technology Division, Joint Bioenergy Institute, 5885 Hollis St, Emeryville, CA, 94608, USA
- Life Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA, 94720, USA
| | - Dominique Loqué
- Feedstocks Division, Joint Bioenergy Institute, 5885 Hollis St, Emeryville, CA, 94608, USA
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA, 94720, USA
| | - Henrik Vibe Scheller
- Feedstocks Division, Joint Bioenergy Institute, 5885 Hollis St, Emeryville, CA, 94608, USA
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA, 94720, USA
- Department of Plant & Microbial Biology, University of California, Berkeley, CA, 94720, USA
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Jirschitzka J, Mattern DJ, Gershenzon J, D'Auria JC. Learning from nature: new approaches to the metabolic engineering of plant defense pathways. Curr Opin Biotechnol 2012; 24:320-8. [PMID: 23141769 DOI: 10.1016/j.copbio.2012.10.014] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Revised: 10/12/2012] [Accepted: 10/18/2012] [Indexed: 12/31/2022]
Abstract
Biotechnological manipulation of plant defense pathways can increase crop resistance to herbivores and pathogens while also increasing yields of medicinal, industrial, flavor and fragrance compounds. The most successful achievements in engineering defense pathways can be attributed to researchers striving to imitate natural plant regulatory mechanisms. For example, the introduction of transcription factors that control several genes in one pathway is often a valuable strategy to increase flux in that pathway. The use of multi-gene cassettes which mimic natural gene clusters can facilitate coordinated regulation of a pathway and speed transformation efforts. The targeting of defense pathway genes to organs and tissues in which the defensive products are typically made and stored can also increase yield as well as defensive potential.
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Affiliation(s)
- Jan Jirschitzka
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Strasse 8, D-07745 Jena, Germany
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