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Senanayake M, Lin CY, Mansfield SD, Eudes A, Davison BH, Pingali SV, O'Neill H. Ectopic Production of 3,4-Dihydroxybenzoate in Planta Affects Cellulose Structure and Organization. Biomacromolecules 2024; 25:3542-3553. [PMID: 38780531 DOI: 10.1021/acs.biomac.4c00187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2024]
Abstract
Lignocellulosic biomass is a highly sustainable and largely carbon dioxide neutral feedstock for the production of biofuels and advanced biomaterials. Although thermochemical pretreatment is typically used to increase the efficiency of cell wall deconstruction, genetic engineering of the major plant cell wall polymers, especially lignin, has shown promise as an alternative approach to reduce biomass recalcitrance. Poplar trees with reduced lignin content and altered composition were previously developed by overexpressing bacterial 3-dehydroshikimate dehydratase (QsuB) enzyme to divert carbon flux from the shikimate pathway. In this work, three transgenic poplar lines with increasing QsuB expression levels and different lignin contents were studied using small-angle neutron scattering (SANS) and wide-angle X-ray scattering (WAXS). SANS showed that although the cellulose microfibril cross-sectional dimension remained unchanged, the ordered organization of the microfibrils progressively decreased with increased QsuB expression. This was correlated with decreasing total lignin content in the QsuB lines. WAXS showed that the crystallite dimensions of cellulose microfibrils transverse to the growth direction were not affected by the QsuB expression, but the crystallite dimensions parallel to the growth direction were decreased by ∼20%. Cellulose crystallinity was also decreased with increased QsuB expression, which could be related to high levels of 3,4-dihydroxybenzoate, the product of QsuB expression, disrupting microfibril crystallization. In addition, the cellulose microfibril orientation angle showed a bimodal distribution at higher QsuB expression levels. Overall, this study provides new structural insights into the impact of ectopic synthesis of small-molecule metabolites on cellulose organization and structure that can be used for future efforts aimed at reducing biomass recalcitrance.
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Affiliation(s)
- Manjula Senanayake
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Chien-Yuan Lin
- Joint BioEnergy Institute, Emeryville, California 94608, United States
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Shawn D Mansfield
- Department of Wood Science, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
- Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Aymerick Eudes
- Joint BioEnergy Institute, Emeryville, California 94608, United States
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Brian H Davison
- BioSciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Sai Venkatesh Pingali
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Hugh O'Neill
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
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2
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Bryant N, Zhang J, Feng K, Shu M, Ployet R, Chen JG, Muchero W, Yoo CG, Tschaplinski TJ, Pu Y, Ragauskas AJ. Novel candidate genes for lignin structure identified through genome-wide association study of naturally varying Populus trichocarpa. FRONTIERS IN PLANT SCIENCE 2023; 14:1153113. [PMID: 37215291 PMCID: PMC10197963 DOI: 10.3389/fpls.2023.1153113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Accepted: 04/03/2023] [Indexed: 05/24/2023]
Abstract
Populus is a promising lignocellulosic feedstock for biofuels and bioproducts. However, the cell wall biopolymer lignin is a major barrier in conversion of biomass to biofuels. To investigate the variability and underlying genetic basis of the complex structure of lignin, a population of 409 three-year-old, naturally varying Populus trichocarpa genotypes were characterized by heteronuclear single quantum coherence (HSQC) nuclear magnetic resonance (NMR). A subsequent genome-wide association study (GWAS) was conducted using approximately 8.3 million single nucleotide polymorphisms (SNPs), which identified 756 genes that were significantly associated (-log10(p-value)>6) with at least one lignin phenotype. Several promising candidate genes were identified, many of which have not previously been reported to be associated with lignin or cell wall biosynthesis. These results provide a resource for gaining insights into the molecular mechanisms of lignin biosynthesis and new targets for future genetic improvement in poplar.
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Affiliation(s)
- Nathan Bryant
- Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, TN, United States
| | - Jin Zhang
- Center for Bioenergy Innovation, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
| | - Kai Feng
- Center for Bioenergy Innovation, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
| | - Mengjun Shu
- Center for Bioenergy Innovation, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
| | - Raphael Ployet
- Center for Bioenergy Innovation, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
| | - Jin-Gui Chen
- Center for Bioenergy Innovation, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
| | - Wellington Muchero
- Center for Bioenergy Innovation, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
| | - Chang Geun Yoo
- Department of Chemical Engineering, State University of New York College of Environmental Science and Forestry, Syracuse, NY, United States
| | - Timothy J. Tschaplinski
- Center for Bioenergy Innovation, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
| | - Yunqiao Pu
- Center for Bioenergy Innovation, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
| | - Arthur J. Ragauskas
- Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, TN, United States
- Center for Bioenergy Innovation, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
- Center for Renewable Carbon, Department of Forestry, Wildlife, and Fisheries, University of Tennessee Institute of Agriculture, Knoxville, TN, United States
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Wang E, Ballachay R, Cai G, Cao Y, Trajano HL. Predicting xylose yield from prehydrolysis of hardwoods: A machine learning approach. FRONTIERS IN CHEMICAL ENGINEERING 2022. [DOI: 10.3389/fceng.2022.994428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Hemicelluloses are amorphous polymers of sugar molecules that make up a major fraction of lignocellulosic biomasses. They have applications in the bioenergy, textile, mining, cosmetic, and pharmaceutical industries. Industrial use of hemicellulose often requires that the polymer be hydrolyzed into constituent oligomers and monomers. Traditional models of hemicellulose degradation are kinetic, and usually only appropriate for limited operating regimes and specific species. The study of hemicellulose hydrolysis has yielded substantial data in the literature, enabling a diverse data set to be collected for general and widely applicable machine learning models. In this paper, a dataset containing 1955 experimental data points on batch hemicellulose hydrolysis of hardwood was collected from 71 published papers dated from 1985 to 2019. Three machine learning models (ridge regression, support vector regression and artificial neural networks) are assessed on their ability to predict xylose yield and compared to a kinetic model. Although the performance of ridge regression was unsatisfactory, both support vector regression and artificial neural networks outperformed the simple kinetic model. The artificial neural network outperformed support vector regression, reducing the mean absolute error in predicting soluble xylose yield of test data to 6.18%. The results suggest that machine learning models trained on historical data may be used to supplement experimental data, reducing the number of experiments needed.
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de Vries L, MacKay HA, Smith RA, Mottiar Y, Karlen SD, Unda F, Muirragui E, Bingman C, Vander Meulen K, Beebe ET, Fox BG, Ralph J, Mansfield SD. pHBMT1, a BAHD-family monolignol acyltransferase, mediates lignin acylation in poplar. PLANT PHYSIOLOGY 2022; 188:1014-1027. [PMID: 34977949 PMCID: PMC8825253 DOI: 10.1093/plphys/kiab546] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 10/26/2021] [Indexed: 05/13/2023]
Abstract
Poplar (Populus) lignin is naturally acylated with p-hydroxybenzoate ester moieties. However, the enzyme(s) involved in the biosynthesis of the monolignol-p-hydroxybenzoates have remained largely unknown. Here, we performed an in vitro screen of the Populus trichocarpa BAHD acyltransferase superfamily (116 genes) using a wheatgerm cell-free translation system and found five enzymes capable of producing monolignol-p-hydroxybenzoates. We then compared the transcript abundance of the five corresponding genes with p-hydroxybenzoate concentrations using naturally occurring unrelated genotypes of P. trichocarpa and revealed a positive correlation between the expression of p-hydroxybenzoyl-CoA monolig-nol transferase (pHBMT1, Potri.001G448000) and p-hydroxybenzoate levels. To test whether pHBMT1 is responsible for the biosynthesis of monolignol-p-hydroxybenzoates, we overexpressed pHBMT1 in hybrid poplar (Populus alba × P. grandidentata) (35S::pHBMT1 and C4H::pHBMT1). Using three complementary analytical methods, we showed that there was an increase in soluble monolignol-p-hydroxybenzoates and cell-wall-bound monolignol-p-hydroxybenzoates in the poplar transgenics. As these pendent groups are ester-linked, saponification releases p-hydroxybenzoate, a precursor to parabens that are used in pharmaceuticals and cosmetics. This identified gene could therefore be used to engineer lignocellulosic biomass with increased value for emerging biorefinery strategies.
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Affiliation(s)
- Lisanne de Vries
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
- US Department of Energy (DOE) Great Lakes Bioenergy Research Center, the Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, Wisconsin 53726, USA
| | - Heather A MacKay
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Rebecca A Smith
- US Department of Energy (DOE) Great Lakes Bioenergy Research Center, the Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, Wisconsin 53726, USA
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Yaseen Mottiar
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
- US Department of Energy (DOE) Great Lakes Bioenergy Research Center, the Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, Wisconsin 53726, USA
| | - Steven D Karlen
- US Department of Energy (DOE) Great Lakes Bioenergy Research Center, the Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, Wisconsin 53726, USA
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Faride Unda
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
- US Department of Energy (DOE) Great Lakes Bioenergy Research Center, the Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, Wisconsin 53726, USA
| | - Emilia Muirragui
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Craig Bingman
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Kirk Vander Meulen
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Emily T Beebe
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Brian G Fox
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - John Ralph
- US Department of Energy (DOE) Great Lakes Bioenergy Research Center, the Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, Wisconsin 53726, USA
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Shawn D Mansfield
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
- US Department of Energy (DOE) Great Lakes Bioenergy Research Center, the Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, Wisconsin 53726, USA
- Author for communication:
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Mahon EL, de Vries L, Jang SK, Middar S, Kim H, Unda F, Ralph J, Mansfield SD. Exogenous chalcone synthase expression in developing poplar xylem incorporates naringenin into lignins. PLANT PHYSIOLOGY 2022; 188:984-996. [PMID: 34718804 PMCID: PMC8825309 DOI: 10.1093/plphys/kiab499] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Accepted: 09/30/2021] [Indexed: 05/03/2023]
Abstract
Lignin, a polyphenolic polymer, is a major chemical constituent of the cell walls of terrestrial plants. The biosynthesis of lignin is a highly plastic process, as highlighted by an increasing number of noncanonical monomers that have been successfully identified in an array of plants. Here, we engineered hybrid poplar (Populus alba x grandidentata) to express chalcone synthase 3 (MdCHS3) derived from apple (Malus domestica) in lignifying xylem. Transgenic trees displayed an accumulation of the flavonoid naringenin in xylem methanolic extracts not inherently observed in wild-type trees. Nuclear magnetic resonance analysis revealed the presence of naringenin in the extract-free, cellulase-treated xylem lignin of MdCHS3-poplar, indicating the incorporation of this flavonoid-derived compound into poplar secondary cell wall lignins. The transgenic trees also displayed lower total cell wall lignin content and increased cell wall carbohydrate content and performed significantly better in limited saccharification assays than their wild-type counterparts.
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Affiliation(s)
- Elizabeth L Mahon
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC, Canada
- US Department of Energy, Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, Madison, Wisconsin, USA
| | - Lisanne de Vries
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC, Canada
- US Department of Energy, Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, Madison, Wisconsin, USA
| | - Soo-Kyeong Jang
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC, Canada
| | - Sandeep Middar
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC, Canada
| | - Hoon Kim
- US Department of Energy, Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, Madison, Wisconsin, USA
| | - Faride Unda
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC, Canada
- US Department of Energy, Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, Madison, Wisconsin, USA
| | - John Ralph
- US Department of Energy, Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, Madison, Wisconsin, USA
- Department of Biochemistry, University of Wisconsin, Madison, Wisconsin, USA
| | - Shawn D Mansfield
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC, Canada
- US Department of Energy, Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, Madison, Wisconsin, USA
- Author for communication:
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6
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Mottiar Y, Mansfield SD. Lignin p-Hydroxybenzoylation Is Negatively Correlated With Syringyl Units in Poplar. FRONTIERS IN PLANT SCIENCE 2022; 13:938083. [PMID: 35937345 PMCID: PMC9355280 DOI: 10.3389/fpls.2022.938083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 06/13/2022] [Indexed: 05/15/2023]
Abstract
The lignin found in the cell walls of poplar fibres is decorated with ester-linked p-hydroxybenzoate moieties that originate from the participation of acylated monolignols in lignin polymerisation. Although little is known about the biological implications of these cell-wall constituents, it has historically been postulated that acylated monolignols might promote lignification in syringyl lignin-rich species such as poplar. However, cell-wall-bound p-hydroxybenzoate groups were negatively correlated with syringyl units in a collection of 316 unrelated genotypes of black cottonwood (Populus trichocarpa). Based upon this observation, several alternative hypotheses on the occurrence of lignin acylation are presented.
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7
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Yu T, Hu Y, Zhang Y, Zhao R, Yan X, Dayananda B, Wang J, Jiao Y, Li J, Yi X. Whole-Genome Sequencing of Acer catalpifolium Reveals Evolutionary History of Endangered Species. Genome Biol Evol 2021; 13:6456308. [PMID: 34878129 PMCID: PMC8677443 DOI: 10.1093/gbe/evab271] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/02/2021] [Indexed: 01/27/2023] Open
Abstract
Acer catalpifolium is an endangered species restricted to remote localities of West China. Understanding the genomic content and evolution of A. catalpifolium is essential to conservation efforts of this rare and ecologically valuable plant. Here, we report a high-quality genome of A. catalpifolium consisting of ∼654 Mbp and ∼35,132 protein-coding genes. We detected 969 positively selected genes in two Acer genomes compared with four other eudicots, 65 of which were transcription factors. We hypothesize that these positively selected mutations in transcription factors might affect their function and thus contribute to A. catalpifolium’s decline-type population. We also identified 179 significantly expanded gene families compared with 12 other eudicots, some of which are involved in stress responses, such as the FRS–FRF family. We inferred that A. catalpifolium has experienced gene family expansions to cope with environmental stress in its evolutionary history. Finally, 109 candidate genes encoding key enzymes in the lignin biosynthesis pathway were identified in A. catalpifolium; of particular note were the large range and high copy number of cinnamyl alcohol dehydrogenase genes. The chromosome-level genome of A. catalpifolium presented here may serve as a fundamental genomic resource for better understanding endangered Acer species, informing future conservation efforts.
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Affiliation(s)
- Tao Yu
- Beijing Key Laboratory for Forest Resources and Ecosystem Processes, Beijing Forestry University, China
| | - Yiheng Hu
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yuyang Zhang
- The National-Local Joint Engineering Laboratory of High Efficiency and Superior-Quality Cultivation and Fruit Deep Processing Technology on Characteristic Fruit Trees, College of Plant Science, Tarim University, Alear, China
| | - Ran Zhao
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Beijing, China
| | - Xueqing Yan
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Buddhi Dayananda
- School of Agriculture and Food Sciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Jinpeng Wang
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yuannian Jiao
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Junqing Li
- Beijing Key Laboratory for Forest Resources and Ecosystem Processes, Beijing Forestry University, China
| | - Xin Yi
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Beijing, China
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8
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Wood and Pulping Properties Variation of Acacia crassicarpa A.Cunn. ex Benth. and Sampling Strategies for Accurate Phenotyping. FORESTS 2020. [DOI: 10.3390/f11101043] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Research Highlights: This study provides a comprehensive set of wood and pulping properties of Acacia crassicarpa A.Cunn. ex Benth. to assess variation and efficient sampling strategies for whole-tree level phenotyping. Background and Objectives: A. crassicarpa is an important tree species in Southeast Asia, with limited knowledge about its wood properties. The objective of this study was to characterize important wood properties and pulping performance of improved germplasm of the species. Furthermore, we investigated within-tree patterns of variation and evaluated the efficiency of phenotyping strategies. Materials and Methods: Second-generation progeny trials were studied, where forty 50-month-old trees were selected for destructive sampling and assessed for wood density, kraft pulp yield, α-cellulose, carbohydrate composition, and lignin content and composition (S/G ratio). We estimated the phenotypic correlations among traits determined within-tree longitudinal variation and its importance for whole-tree level phenotyping. Results: The mean whole-tree disc basic density was 481 kg/m3, and the screened kraft pulp yield was 53.8%. The reliabilities of each sampling position to predict whole-tree properties varied with different traits. For basic density, pulp yield, and glucose content, the ground-level sampling could reliably predict the whole-tree property. With near infrared reflectance spectroscopy predictions as an indirect measurement method for disc basic density, we verified reduced reliability values for breast height sampling but sufficiently correlated to allow accurate ranking and efficient selection of genotypes in a breeding program context. Conclusions: We demonstrated the quality of A. crassicarpa as a wood source for the pulping industry. The wood and pulping traits have high levels of phenotypic variation, and standing tree sampling strategies can be performed for both ranking and high-accuracy phenotyping purposes.
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9
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Thornburg NE, Pecha MB, Brandner DG, Reed ML, Vermaas JV, Michener WE, Katahira R, Vinzant TB, Foust TD, Donohoe BS, Román-Leshkov Y, Ciesielski PN, Beckham GT. Mesoscale Reaction-Diffusion Phenomena Governing Lignin-First Biomass Fractionation. CHEMSUSCHEM 2020; 13:4495-4509. [PMID: 32246557 DOI: 10.1002/cssc.202000558] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Indexed: 05/21/2023]
Abstract
Lignin solvolysis from the plant cell wall is the critical first step in lignin depolymerization processes involving whole biomass feedstocks. However, little is known about the coupled reaction kinetics and transport phenomena that govern the effective rates of lignin extraction. Here, we report a validated simulation framework that determines intrinsic, transport-independent kinetic parameters for the solvolysis of lignin, hemicellulose, and cellulose upon incorporation of feedstock characteristics for the methanol-based extraction of poplar as an example fractionation process. Lignin fragment diffusion is predicted to compete on the same time and length scales as reactions of lignin within cell walls and longitudinal pores of typical milled particle sizes, and mass transfer resistances are predicted to dominate the solvolysis of poplar particles that exceed approximately 2 mm in length. Beyond the approximately 2 mm threshold, effectiveness factors are predicted to be below 0.25, which implies that pore diffusion resistances may attenuate observable kinetic rate measurements by at least 75 % in such cases. Thus, researchers are recommended to conduct kinetic evaluations of lignin-first catalysts using biomass particles smaller than approximately 0.2 mm in length to avoid feedstock-specific mass transfer limitations in lignin conversion studies. Overall, this work highlights opportunities to improve lignin solvolysis by genetic engineering and provides actionable kinetic information to guide the design and scale-up of emerging biorefinery strategies.
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Affiliation(s)
- Nicholas E Thornburg
- National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO, 80401, USA
| | - M Brennan Pecha
- Biosciences Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO, 80401, USA
| | - David G Brandner
- National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO, 80401, USA
| | - Michelle L Reed
- Biosciences Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO, 80401, USA
| | - Josh V Vermaas
- Biosciences Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO, 80401, USA
| | - William E Michener
- Biosciences Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO, 80401, USA
| | - Rui Katahira
- National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO, 80401, USA
| | - Todd B Vinzant
- Biosciences Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO, 80401, USA
| | - Thomas D Foust
- National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO, 80401, USA
| | - Bryon S Donohoe
- Biosciences Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO, 80401, USA
| | - Yuriy Román-Leshkov
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA
| | - Peter N Ciesielski
- Biosciences Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO, 80401, USA
| | - Gregg T Beckham
- National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO, 80401, USA
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10
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Si J, Quan M, Xiao L, Xie J, Du Q, Zhang D. Genetic interactions among Pto-miR319 family members and their targets influence growth and wood properties in Populus tomentosa. Mol Genet Genomics 2020; 295:855-870. [PMID: 32361785 DOI: 10.1007/s00438-020-01667-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 03/16/2020] [Indexed: 11/25/2022]
Abstract
MicroRNAs (miRNAs) play crucial roles in all aspects of plant growth and development, but the genetic interactions of miRNAs and their target genes in woody plants are largely unknown. Here, we integrated association genetics and expression profiling to decipher the allelic variations and interactions of the Pto-MIR319 family of miRNAs and 12 putative Pto-miR319 target genes related to wood formation in 435 unrelated individuals of Populus tomentosa Carrière (Chinese white poplar). Expression pattern analysis showed that among all pairings between expressions of pre-miRNA of Pto-MIR319 members and targets, 70.0% showed negative correlation of expression levels (r = - 0.944 to 0.674, P < 0.01) in eight tissues and organs of poplar, suggesting that Pto-miR319 may participate in the regulatory network of wood formation. Single SNP-based association studies identified 137 significant associations (P < 0.01, Q < 0.1), representing 126 unique SNPs from Pto-MIR319 members and their targets, with 10 tree growth traits, revealing that these genetic factors have common roles related to wood formation. Epistasis analysis uncovered 105 significant SNP-SNP associations (P < 0.01) influencing the 10 traits, demonstrating the close genetic interactions between Pto-MIR319 family members and the 12 Pto-miR319 target genes. Notably, one common SNP, in the precursor region of Pto-MIR319e, affected the stability of Pto-MIR319e's secondary structure by altering the stem-loop structure and minimum free energy, contributing to variations in the expression of Pto-MIR319e and Pto-miR319e target genes. This study enriches the understanding of the functions of miR319 family miRNAs in poplar and exemplifies a feasible approach to exploring the genetic effects underlying miRNA-mRNA interactions related to complex traits in trees.
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Affiliation(s)
- Jingna Si
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, P. R. China.,Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, P. R. China
| | - Mingyang Quan
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, P. R. China.,Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, P. R. China.,Beijing Advanced Innovation Center for Tree Breeding By Molecular Design, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, P. R. China
| | - Liang Xiao
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, P. R. China.,Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, P. R. China
| | - Jianbo Xie
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, P. R. China.,Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, P. R. China
| | - Qingzhang Du
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, P. R. China.,Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, P. R. China.,Beijing Advanced Innovation Center for Tree Breeding By Molecular Design, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, P. R. China
| | - Deqiang Zhang
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, P. R. China. .,Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, P. R. China. .,Beijing Advanced Innovation Center for Tree Breeding By Molecular Design, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, P. R. China.
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11
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Wang S, Yamaguchi M, Grienenberger E, Martone PT, Samuels AL, Mansfield SD. The Class II KNOX genes KNAT3 and KNAT7 work cooperatively to influence deposition of secondary cell walls that provide mechanical support to Arabidopsis stems. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 101:293-309. [PMID: 31587430 DOI: 10.1111/tpj.14541] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 08/01/2019] [Accepted: 08/09/2019] [Indexed: 05/10/2023]
Abstract
The transcription factor KNOTTED ARABIDOPSIS THALIANA7 (KNAT7) is a Class II KNOTTED1-like homeobox (KNOX2) gene that, in interfascicular fibres, acts as a negative regulator of secondary cell wall biosynthesis. In addition, knat7 loss-of-function mutants display an irregular xylem (irx) phenotype, suggesting a potential positive regulatory role in xylem vessel secondary cell wall deposition. Although our understanding of the role of KNAT7 is evolving, the function(s) of the closely related KNOX2 genes, KNAT3, KNAT4, and KNAT5, in secondary wall formation still remain unclear. We found that all four Arabidopsis KNOX2 genes were expressed in the inflorescence stems. However, only the knat3 knat7 double mutants showed a phenotype, displaying an enhanced irx phenotypes relative to the single mutants, as well as decreased interfascicular fibre cell wall thickness. Moreover, knat3 knat7 double mutants had reduced stem tensile and flexural strength compared with wild-type and single mutants. In contrast, KNAT3 overexpression resulted in thicker interfascicular fibre secondary cell walls in inflorescence stems, suggesting a potential positive regulation in interfascicular fibre secondary wall development. This work identifies KNAT3 as a potential transcriptional activator working together with KNAT7 to promote secondary cell wall biosynthesis in xylem vessels, while concurrently acting antagonistically with KNAT7 to influence secondary wall formation in interfascicular fibres.
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Affiliation(s)
- Shumin Wang
- Department of Botany, University of British Columbia, Vancouver, BC, Canada
| | - Masatoshi Yamaguchi
- Graduate School of Science and Engineering, Saitama University, Saitama, Japan
| | - Etienne Grienenberger
- Institut de biologie moléculaire des plantes (IBMP), CNRS UPR 2357, Strasbourg, France
| | - Patrick T Martone
- Department of Botany, University of British Columbia, Vancouver, BC, Canada
| | - A Lacey Samuels
- Department of Botany, University of British Columbia, Vancouver, BC, Canada
| | - Shawn D Mansfield
- Department of Wood Science, University of British Columbia, Vancouver, BC, Canada
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12
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Guerra FP, Suren H, Holliday J, Richards JH, Fiehn O, Famula R, Stanton BJ, Shuren R, Sykes R, Davis MF, Neale DB. Exome resequencing and GWAS for growth, ecophysiology, and chemical and metabolomic composition of wood of Populus trichocarpa. BMC Genomics 2019; 20:875. [PMID: 31747881 PMCID: PMC6864938 DOI: 10.1186/s12864-019-6160-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Accepted: 10/09/2019] [Indexed: 12/26/2022] Open
Abstract
Background Populus trichocarpa is an important forest tree species for the generation of lignocellulosic ethanol. Understanding the genomic basis of biomass production and chemical composition of wood is fundamental in supporting genetic improvement programs. Considerable variation has been observed in this species for complex traits related to growth, phenology, ecophysiology and wood chemistry. Those traits are influenced by both polygenic control and environmental effects, and their genome architecture and regulation are only partially understood. Genome wide association studies (GWAS) represent an approach to advance that aim using thousands of single nucleotide polymorphisms (SNPs). Genotyping using exome capture methodologies represent an efficient approach to identify specific functional regions of genomes underlying phenotypic variation. Results We identified 813 K SNPs, which were utilized for genotyping 461 P. trichocarpa clones, representing 101 provenances collected from Oregon and Washington, and established in California. A GWAS performed on 20 traits, considering single SNP-marker tests identified a variable number of significant SNPs (p-value < 6.1479E-8) in association with diameter, height, leaf carbon and nitrogen contents, and δ15N. The number of significant SNPs ranged from 2 to 220 per trait. Additionally, multiple-marker analyses by sliding-windows tests detected between 6 and 192 significant windows for the analyzed traits. The significant SNPs resided within genes that encode proteins belonging to different functional classes as such protein synthesis, energy/metabolism and DNA/RNA metabolism, among others. Conclusions SNP-markers within genes associated with traits of importance for biomass production were detected. They contribute to characterize the genomic architecture of P. trichocarpa biomass required to support the development and application of marker breeding technologies.
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Affiliation(s)
- Fernando P Guerra
- Department of Plant Sciences, University of California at Davis, 262C Robbins Hall, Mail Stop 4, Davis, CA, 95616, USA.,Instituto de Ciencias Biológicas, Universidad de Talca, Talca, P.O. Box 747, 3460000, Chile
| | - Haktan Suren
- Department of Forest Resources and Environmental Conservation, Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061, USA
| | - Jason Holliday
- Department of Forest Resources and Environmental Conservation, Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061, USA
| | - James H Richards
- Department of Land, Air and Water Resources, University of California, Davis, CA, 95616, USA
| | - Oliver Fiehn
- Department of Molecular and Cellular Biology & Genome Center, University of California, Davis, CA, 95616, USA
| | - Randi Famula
- Department of Plant Sciences, University of California at Davis, 262C Robbins Hall, Mail Stop 4, Davis, CA, 95616, USA
| | - Brian J Stanton
- Biological Research Group, GreenWood Resources, Portland, OR, 97201, USA
| | - Richard Shuren
- Biological Research Group, GreenWood Resources, Portland, OR, 97201, USA
| | - Robert Sykes
- National Renewable Energy Laboratory, Golden, CO, 80401, USA
| | - Mark F Davis
- National Renewable Energy Laboratory, Golden, CO, 80401, USA
| | - David B Neale
- Department of Plant Sciences, University of California at Davis, 262C Robbins Hall, Mail Stop 4, Davis, CA, 95616, USA. .,Bioenergy Research Center, University of California at Davis, Davis, CA, 95616, USA.
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13
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Taylor G, Donnison IS, Murphy-Bokern D, Morgante M, Bogeat-Triboulot MB, Bhalerao R, Hertzberg M, Polle A, Harfouche A, Alasia F, Petoussi V, Trebbi D, Schwarz K, Keurentjes JJB, Centritto M, Genty B, Flexas J, Grill E, Salvi S, Davies WJ. Sustainable bioenergy for climate mitigation: developing drought-tolerant trees and grasses. ANNALS OF BOTANY 2019; 124:513-520. [PMID: 31665761 PMCID: PMC6821384 DOI: 10.1093/aob/mcz146] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 09/23/2019] [Indexed: 05/29/2023]
Abstract
BACKGROUND AND AIMS Bioenergy crops are central to climate mitigation strategies that utilize biogenic carbon, such as BECCS (bioenergy with carbon capture and storage), alongside the use of biomass for heat, power, liquid fuels and, in the future, biorefining to chemicals. Several promising lignocellulosic crops are emerging that have no food role - fast-growing trees and grasses - but are well suited as bioenergy feedstocks, including Populus, Salix, Arundo, Miscanthus, Panicum and Sorghum. SCOPE These promising crops remain largely undomesticated and, until recently, have had limited germplasm resources. In order to avoid competition with food crops for land and nature conservation, it is likely that future bioenergy crops will be grown on marginal land that is not needed for food production and is of poor quality and subject to drought stress. Thus, here we define an ideotype for drought tolerance that will enable biomass production to be maintained in the face of moderate drought stress. This includes traits that can readily be measured in wide populations of several hundred unique genotypes for genome-wide association studies, alongside traits that are informative but can only easily be assessed in limited numbers or training populations that may be more suitable for genomic selection. Phenotyping, not genotyping, is now the major bottleneck for progress, since in all lignocellulosic crops studied extensive use has been made of next-generation sequencing such that several thousand markers are now available and populations are emerging that will enable rapid progress for drought-tolerance breeding. The emergence of novel technologies for targeted genotyping by sequencing are particularly welcome. Genome editing has already been demonstrated for Populus and offers significant potential for rapid deployment of drought-tolerant crops through manipulation of ABA receptors, as demonstrated in Arabidopsis, with other gene targets yet to be tested. CONCLUSIONS Bioenergy is predicted to be the fastest-developing renewable energy over the coming decade and significant investment over the past decade has been made in developing genomic resources and in collecting wild germplasm from within the natural ranges of several tree and grass crops. Harnessing these resources for climate-resilient crops for the future remains a challenge but one that is likely to be successful.
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Affiliation(s)
- G Taylor
- School of Biological Sciences, University of Southampton, Southampton, UK
- Department of Plant Sciences, University of California at Davis, Davis, CA, USA
| | - I S Donnison
- Institute of Biological, Environmental & Rural Sciences (IBERS), Aberystwyth University, Plas Gogerddan, Aberystwyth, Ceredigion, UK
| | | | - M Morgante
- Department of Agricultural and Environmental Sciences, University of Udine, Via delle Scienze, Udine, Italy
| | | | - R Bhalerao
- Department of Forest Genetics and Plant Physiology, Umea Plant Sciences Centre, Swedish University of Agricultural Sciences, Umea, Sweden
| | - M Hertzberg
- SweTree Technologies AB, SE-904 03 Umeå, Sweden
| | - A Polle
- Büsgen‐Institute, Department of Forest Botany and Tree Physiology, Georg‐August University, Göttingen, Germany
| | - A Harfouche
- Department for Innovation in Biological, Agro-food and Forest Systems, University of Tuscia, Viterbo, Italy
| | - F Alasia
- Franco Alasia Vivai, Strada Solerette, Savigliano, Italy
| | - V Petoussi
- Department of Sociology, University of Crete, Rethymno, Greece
| | - D Trebbi
- Geneticlab, Via Roveredo, Pordenone, Italy
| | - K Schwarz
- Julius Kühn‐Institut (JKI) Bundesforschungsinstitut für Kulturpflanzen, Institute for Crop and Soil Science, Bundesallee 50, D‐38116 Braunschweig, Germany
| | - J J B Keurentjes
- Laboratory of Genetics, Wageningen University & Research, Droevendaalsesteeg, Wageningen, The Netherlands
| | - M Centritto
- Trees and Timber Institute, National Research Council of Italy, Sesto Fiorentino, Italy
| | - B Genty
- Aix-Marseille University, CEA, CNRS, BIAM, UMR 7265, Saint Paul lez Durance, France
| | - J Flexas
- Research Group on Plant Biology under Mediterranean Conditions, Departament de Biologia, Universitat de les Illes Balears, Carretera de Valldemossa, Palma de Mallorca, Illes Balears, Spain
| | - E Grill
- Lehrstuhl für Botanik, Technische Universität München, Freising, Germany
| | - S Salvi
- Department of Agricultural and Food Sciences, University of Bologna, Viale Fanin, Bologna, Italy
| | - W J Davies
- Lancaster Environment Centre, Lancaster University, Lancaster, UK
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14
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Allona I, Kirst M, Boerjan W, Strauss S, Sederoff R. Editorial: Forest Genomics and Biotechnology. FRONTIERS IN PLANT SCIENCE 2019; 10:1187. [PMID: 31681350 PMCID: PMC6806019 DOI: 10.3389/fpls.2019.01187] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2019] [Accepted: 08/29/2019] [Indexed: 06/10/2023]
Affiliation(s)
- Isabel Allona
- Centro de Biotecnología y Genómica de Plantas (CBGP, UPM-INIA), Universidad Politécnica de Madrid (UPM) - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus de Montegancedo, Pozuelo de Alarcón, Madrid, Spain
- Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid (UPM), Madrid, Spain
| | - Matias Kirst
- School of Forest Resources and Conservation, University of Florida, Gainesville, FL, United States
| | - Wout Boerjan
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Center for Plant Systems Biology, VIB, Ghent, Belgium
| | - Steven Strauss
- Department of Forest Ecosystems and Society, Oregon State University, Corvallis, OR, United States
| | - Ronald Sederoff
- Department of Forestry and Environmental Resources, North Carolina State University, Raleigh, NC, United States
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15
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Weighill D, Tschaplinski TJ, Tuskan GA, Jacobson D. Data Integration in Poplar: 'Omics Layers and Integration Strategies. Front Genet 2019; 10:874. [PMID: 31608114 PMCID: PMC6773870 DOI: 10.3389/fgene.2019.00874] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2019] [Accepted: 08/20/2019] [Indexed: 12/20/2022] Open
Abstract
Populus trichocarpa is an important biofuel feedstock that has been the target of extensive research and is emerging as a model organism for plants, especially woody perennials. This research has generated several large ‘omics datasets. However, only few studies in Populus have attempted to integrate various data types. This review will summarize various ‘omics data layers, focusing on their application in Populus species. Subsequently, network and signal processing techniques for the integration and analysis of these data types will be discussed, with particular reference to examples in Populus.
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Affiliation(s)
- Deborah Weighill
- The Bredesen Center for Interdisciplinary Research and Graduate Education, University of Tennessee, Knoxville, Knoxville, TN, United States.,Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
| | - Timothy J Tschaplinski
- The Bredesen Center for Interdisciplinary Research and Graduate Education, University of Tennessee, Knoxville, Knoxville, TN, United States.,Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
| | - Gerald A Tuskan
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
| | - Daniel Jacobson
- The Bredesen Center for Interdisciplinary Research and Graduate Education, University of Tennessee, Knoxville, Knoxville, TN, United States.,Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
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16
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Indole-3-acetic acid has long-term effects on long non-coding RNA gene methylation and growth in Populus tomentosa. Mol Genet Genomics 2019; 294:1511-1525. [DOI: 10.1007/s00438-019-01593-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Accepted: 07/05/2019] [Indexed: 01/07/2023]
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17
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Marco de Lima B, Cappa EP, Silva-Junior OB, Garcia C, Mansfield SD, Grattapaglia D. Quantitative genetic parameters for growth and wood properties in Eucalyptus "urograndis" hybrid using near-infrared phenotyping and genome-wide SNP-based relationships. PLoS One 2019; 14:e0218747. [PMID: 31233563 PMCID: PMC6590816 DOI: 10.1371/journal.pone.0218747] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Accepted: 06/07/2019] [Indexed: 12/30/2022] Open
Abstract
A thorough understanding of the heritability, genetic correlations and additive and non-additive variance components of tree growth and wood properties is a requisite for effective tree breeding. This knowledge is essential to maximize genetic gain, that is, the amount of increase in trait performance achieved annually through directional selection. Understanding the genetic attributes of traits targeted by breeding is also important to sustain decade-long genetic progress, that is, the progress made by increasing the average genetic value of the offspring as compared to that of the parental generation. In this study, we report quantitative genetic parameters for fifteen growth, wood chemical and physical traits for the world-famous Eucalyptus urograndis hybrid (E. grandis × E. urophylla). These traits directly impact the optimal use of wood for cellulose pulp, paper, and energy production. A population of 1,000 trees sampled in a progeny trial was phenotyped directly or following the development and use of near-infrared spectroscopy calibration models. Trees were genotyped with 33,398 SNPs and 24,001 DArT-seq genome-wide markers and genomic realized relationship matrices (GRM) were used for parameter estimation with an individual-tree additive-dominant mixed model. Wood chemical properties and wood density showed stronger genetic control than growth, cellulose and fiber traits. Additive effects are the main drivers of genetic variation for all traits, but dominance plays an equally or more important role for growth, singularly in this hybrid. GRM´s with >10,000 markers provided stable relationships estimates and more accurate parameters than pedigrees by capturing the full genetic relationships among individuals and disentangling the non-additive from the additive genetic component. Low correlations between growth and wood properties indicate that simultaneous selection for wood traits can be applied with minor effects on genetic gain for growth. Conversely, moderate to strong correlations between wood density and chemical traits exist, likely due to their interdependency on cell wall structure such that responses to selection will be connected for these traits. Our results illustrate the advantage of using genome-wide marker data to inform tree breeding in general and have important consequences for operational breeding of eucalypt urograndis hybrids.
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Affiliation(s)
- Bruno Marco de Lima
- EMBRAPA Genetic Resources and Biotechnology, Brasilia, DF, Brazil
- Department of Genetics, University of São Paulo, Piracicaba, SP, Brazil
| | - Eduardo P. Cappa
- Instituto de Recursos Biológicos, Centro de Investigación en Recursos Naturales, Instituto Nacional de Tecnología Agropecuaria (INTA), Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Orzenil B. Silva-Junior
- EMBRAPA Genetic Resources and Biotechnology, Brasilia, DF, Brazil
- Graduate Program in Genomic Sciences, Universidade Católica de Brasília, Brasília, DF, Brazil
| | | | - Shawn D. Mansfield
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, British Columbia, Canada
| | - Dario Grattapaglia
- EMBRAPA Genetic Resources and Biotechnology, Brasilia, DF, Brazil
- Graduate Program in Genomic Sciences, Universidade Católica de Brasília, Brasília, DF, Brazil
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18
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Hallingbäck HR, Berlin S, Nordh NE, Weih M, Rönnberg-Wästljung AC. Genome Wide Associations of Growth, Phenology, and Plasticity Traits in Willow [ Salix viminalis (L.)]. FRONTIERS IN PLANT SCIENCE 2019; 10:753. [PMID: 31249579 PMCID: PMC6582754 DOI: 10.3389/fpls.2019.00753] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 05/23/2019] [Indexed: 05/10/2023]
Abstract
The short rotation biomass crop willow (Salix genera) has been of interest for bioenergy but recently also for biofuel production. For a faster development of new varieties molecular markers could be used as selection tool in an early stage of the breeding cycle. To identify markers associated with growth traits, genome-wide association mapping was conducted using a population of 291 Salix viminalis accessions collected across Europe and Russia and a large set of genotyping-by-sequencing markers. The accessions were vegetatively propagated and planted in replicated field experiments, one in Southern Sweden and one in Central Sweden. Phenology data, including bud burst and leaf senescence, as well as different growth traits were collected and measured repeatedly between 2010 and 2017 at both field environments. A value of the plasticity for each accession was calculated for all traits that were measured the same year in both environments as the normalized accession value in one environment subtracted by the corresponding value in the other environment. Broad-sense accession heritabilities and narrow-sense chip heritabilities ranged from 0.68 to 0.95 and 0.45 to 0.99, respectively for phenology traits and from 0.56 to 0.85 and 0.24 to 0.97 for growth traits indicating a considerable genetic component for most traits. Population structure and kinship between accessions were taken into account in the association analyses. In total, 39 marker-trait associations were found where four were specifically connected to plasticity and interestingly one particular marker was associated to several different plasticity growth traits. Otherwise association consistency was poor, possibly due to accession by environment interactions which were demonstrated by the low structure adjusted accession correlations across environments (ranging from 0.40 to 0.58). However, one marker association with biomass fresh weight was repeatedly observed in the same environment over two harvest years. For some traits where several associations were found, the markers jointly explained over 20% of the accession variation. The result from this study using a population of unrelated accessions has given useful information about marker-trait associations especially highlighting marker-plasticity associations and genotype-by-environment interactions as important factors to take account of in future strategies of Salix breeding.
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Affiliation(s)
- Henrik R. Hallingbäck
- Department of Plant Biology, Uppsala BioCenter, Linnean Centre for Plant Biology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Sofia Berlin
- Department of Plant Biology, Uppsala BioCenter, Linnean Centre for Plant Biology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Nils-Erik Nordh
- Department of Crop Production Ecology, Linnean Centre for Plant Biology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Martin Weih
- Department of Crop Production Ecology, Linnean Centre for Plant Biology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Ann-Christin Rönnberg-Wästljung
- Department of Plant Biology, Uppsala BioCenter, Linnean Centre for Plant Biology, Swedish University of Agricultural Sciences, Uppsala, Sweden
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19
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Ohlsson JA, Hallingbäck HR, Jebrane M, Harman-Ware AE, Shollenberger T, Decker SR, Sandgren M, Rönnberg-Wästljung AC. Genetic variation of biomass recalcitrance in a natural Salix viminalis (L.) population. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:135. [PMID: 31171936 PMCID: PMC6545741 DOI: 10.1186/s13068-019-1479-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 05/25/2019] [Indexed: 05/21/2023]
Abstract
BACKGROUND Salix spp. are high-productivity crops potentially used for lignocellulosic biofuels such as bioethanol. In general, pretreatment is needed to facilitate the enzymatic depolymerization process. Biomass resistance to degradation, i.e., biomass recalcitrance, is a trait which can be assessed by measuring the sugar released after combined pretreatment and enzymatic hydrolysis. We have examined genetic parameters of enzymatic sugar release and other traits related to biorefinery use in a population of 286 natural Salix viminalis clones. Furthermore, we have evaluated phenotypic and genetic correlations between these traits and performed a genomewide association mapping analysis using a set of 19,411 markers. RESULTS Sugar release (glucose and xylose) after pretreatment and enzymatic saccharification proved highly variable with large genetic and phenotypic variations, and chip heritability estimates (h 2) of 0.23-0.29. Lignin syringyl/guaiacyl (S/G) ratio and wood density were the most heritable traits (h 2 = 0.42 and 0.59, respectively). Sugar release traits were positively correlated, phenotypically and genetically, with biomass yield and lignin S/G ratio. Association mapping revealed seven marker-trait associations below a suggestive significance threshold, including one marker associated with glucose release. CONCLUSIONS We identified lignin S/G ratio and shoot diameter as heritable traits that could be relatively easily evaluated by breeders, making them suitable proxy traits for developing low-recalcitrance varieties. One marker below the suggestive threshold for marker associations was identified for sugar release, meriting further investigation while also highlighting the difficulties in employing genomewide association mapping for complex traits.
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Affiliation(s)
- Jonas A. Ohlsson
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Henrik R. Hallingbäck
- Department of Plant Biology, Uppsala BioCenter, Linnean Centre for Plant Biology, Swedish University of Agricultural Sciences, P.O. Box 7080, 750 07 Uppsala, Sweden
- Department of Plant Physiology and Forest Genetics, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Mohamed Jebrane
- Department of Forest Biomaterials and Technology/Wood Science, Swedish University of Agricultural Sciences, Box 7008, 750 07 Uppsala, Sweden
| | - Anne E. Harman-Ware
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO USA
- Center for Bioenergy Innovation, National Renewable Energy Laboratory, Golden, CO USA
| | - Todd Shollenberger
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO USA
| | - Stephen R. Decker
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO USA
| | - Mats Sandgren
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Ann-Christin Rönnberg-Wästljung
- Department of Plant Biology, Uppsala BioCenter, Linnean Centre for Plant Biology, Swedish University of Agricultural Sciences, P.O. Box 7080, 750 07 Uppsala, Sweden
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20
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Tuskan GA, Muchero W, Tschaplinski TJ, Ragauskas AJ. Population-level approaches reveal novel aspects of lignin biosynthesis, content, composition and structure. Curr Opin Biotechnol 2019; 56:250-257. [PMID: 30925430 DOI: 10.1016/j.copbio.2019.02.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 02/20/2019] [Accepted: 02/22/2019] [Indexed: 10/27/2022]
Abstract
Population-level studies enabled by high-throughput phenotyping have revealed significant variation in lignin characteristics including content, S:G:H ratio, inter-unit linkage distributions, and molecular weights across multiple plant species. Coupled with genome-wide association mapping studies (GWAS) targeted at linking genetic mutations to phenotype, significant progress has been made in associating putative causal mutations to variation in lignin characteristics. Despite this progress, there are few examples, in which these associations have been molecularly validated to provide new insights into the genetic regulation of lignin biosynthesis. Given a recent report of a GWAS-discovered 5-enolpyruvylshikimate-3-phosphate (EPSP) synthase moonlighting as a transcriptional regulator of lignin biosynthesis, the potential to bridge scientific disciplines in order to uncover hidden elements of lignin biosynthesis has been demonstrated, offering a path to alter lignin characteristics via genetic manipulation in order to expedite lignin valorization. To maximize this potential, however, there is a crucial need for (1) broader surveys of naturally varying diverse plant populations and (2) analytical platforms that can resolve subtle properties at fine chemical and biological scales.
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Affiliation(s)
- Gerald A Tuskan
- Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States.
| | - Wellington Muchero
- Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States
| | - Timothy J Tschaplinski
- Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States
| | - Arthur J Ragauskas
- Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States; University of Tennessee Governor's Chair, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States
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Wang L, Du Q, Xie J, Zhou D, Chen B, Yang H, Zhang D. Genetic variation in transcription factors and photosynthesis light-reaction genes regulates photosynthetic traits. TREE PHYSIOLOGY 2018; 38:1871-1885. [PMID: 30032300 DOI: 10.1093/treephys/tpy079] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 06/19/2018] [Indexed: 06/08/2023]
Abstract
Transcription factors (TFs) play crucial roles in regulating the production of the components required for photosynthesis; elucidating the mechanisms by which underlying genetic variation in TFs affects complex photosynthesis-related traits may improve our understanding of photosynthesis and identify ways to improve photosynthetic efficiency. Promoter analysis of 96 nuclear-encoded Populus tomentosa Carr. genes within this pathway revealed 47 motifs responsive to light, stress, hormones and organ-specific regulation, as well as 86 TFs that might bind these motifs. Using phenotype-genotype associations, we identified 244 single-nucleotide polymorphisms (SNPs) within 105 genes associated with 12 photosynthesis-related traits. Most (30.33%) of these SNPs were located in intronic regions and these SNPs explained 18.66% of the mean phenotypic variation in the photosynthesis-related traits. Additionally, expression quantitative trait loci (eQTL) mapping identified 216 eQTLs associated with 110 eGenes (genes regulated by eQTLs), explaining 14.12% of the variability of gene expression. The lead SNPs of 12.04% of the eQTLs also contributed to phenotypic variation. Among these, a SNP in zf-Dof 5.6 (G120_9287) affected photosynthesis by modulating the expression of a sub-regulatory network of eight other TFs, which in turn regulate 55 photosynthesis-related genes. Furthermore, epistasis analysis identified a large interacting network representing 732 SNP-SNP pairs, of which 354 were photosynthesis gene-TF pairs, emphasizing the important roles of TFs in affecting photosynthesis-related traits. We combined eQTL and epistasis analysis and found 32 TFs harboring eQTLs being epistatic to their targets (identified by eQTL analysis), of which 15 TFs were also associated with photosynthesis traits. We therefore constructed a schematic model of TFs involved in regulating the photosynthetic light reaction pathway. Taken together, our results provide insight into the genetic regulation of photosynthesis, and may drive progress in the marker-assisted selection of desirable P. tomentosa genotypes with more efficient photosynthesis.
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Affiliation(s)
- Longxin Wang
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
| | - Qingzhang Du
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
| | - Jianbo Xie
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
| | - Daling Zhou
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
| | - Beibei Chen
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
| | - Haijiao Yang
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
| | - Deqiang Zhang
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
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Improving wood properties for wood utilization through multi-omics integration in lignin biosynthesis. Nat Commun 2018; 9:1579. [PMID: 29679008 PMCID: PMC5910405 DOI: 10.1038/s41467-018-03863-z] [Citation(s) in RCA: 122] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 03/16/2018] [Indexed: 11/21/2022] Open
Abstract
A multi-omics quantitative integrative analysis of lignin biosynthesis can advance the strategic engineering of wood for timber, pulp, and biofuels. Lignin is polymerized from three monomers (monolignols) produced by a grid-like pathway. The pathway in wood formation of Populus trichocarpa has at least 21 genes, encoding enzymes that mediate 37 reactions on 24 metabolites, leading to lignin and affecting wood properties. We perturb these 21 pathway genes and integrate transcriptomic, proteomic, fluxomic and phenomic data from 221 lines selected from ~2000 transgenics (6-month-old). The integrative analysis estimates how changing expression of pathway gene or gene combination affects protein abundance, metabolic-flux, metabolite concentrations, and 25 wood traits, including lignin, tree-growth, density, strength, and saccharification. The analysis then predicts improvements in any of these 25 traits individually or in combinations, through engineering expression of specific monolignol genes. The analysis may lead to greater understanding of other pathways for improved growth and adaptation. A systematic analysis of lignin biosynthetic genes to quantitatively understand their effect on wood properties is still lacking. Here, the authors integrate transcriptomic, proteomic, fluxomic and phenomic data to quantify the impact of perturbations of transcript abundance on lignin biosynthesis and wood properties.
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23
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Phenotypic and Genotypic Correlations for Wood Properties of Hybrid Poplar Clones of Southern Quebec. FORESTS 2018. [DOI: 10.3390/f9030140] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Escamez S, Latha Gandla M, Derba-Maceluch M, Lundqvist SO, Mellerowicz EJ, Jönsson LJ, Tuominen H. A collection of genetically engineered Populus trees reveals wood biomass traits that predict glucose yield from enzymatic hydrolysis. Sci Rep 2017; 7:15798. [PMID: 29150693 PMCID: PMC5693926 DOI: 10.1038/s41598-017-16013-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 11/06/2017] [Indexed: 11/09/2022] Open
Abstract
Wood represents a promising source of sugars to produce bio-based renewables, including biofuels. However, breaking down lignocellulose requires costly pretreatments because lignocellulose is recalcitrant to enzymatic saccharification. Increasing saccharification potential would greatly contribute to make wood a competitive alternative to petroleum, but this requires improving wood properties. To identify wood biomass traits associated with saccharification, we analyzed a total of 65 traits related to wood chemistry, anatomy and structure, biomass production and saccharification in 40 genetically engineered Populus tree lines. These lines exhibited broad variation in quantitative traits, allowing for multivariate analyses and mathematical modeling. Modeling revealed that seven wood biomass traits associated in a predictive manner with saccharification of glucose after pretreatment. Four of these seven traits were also negatively associated with biomass production, suggesting a trade-off between saccharification potential and total biomass, which has previously been observed to offset the overall sugar yield from whole trees. We therefore estimated the "total-wood glucose yield" (TWG) from whole trees and found 22 biomass traits predictive of TWG after pretreatment. Both saccharification and TWG were associated with low abundant, often overlooked matrix polysaccharides such as arabinose and rhamnose which possibly represent new markers for improved Populus feedstocks.
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Affiliation(s)
- Sacha Escamez
- Department of Plant Physiology, Umeå University, Umeå Plant Science Centre (UPSC), SE-901 87, Umeå, Sweden.
| | | | - Marta Derba-Maceluch
- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå Plant Science Centre (UPSC), SE-901 83, Umeå, Sweden
| | - Sven-Olof Lundqvist
- INNVENTIA AB, RISE Bioeconomy, Drottning Kristinas väg 61 B, SE-114 28, Stockholm, Sweden
| | - Ewa J Mellerowicz
- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå Plant Science Centre (UPSC), SE-901 83, Umeå, Sweden
| | - Leif J Jönsson
- Department of Chemistry, Umeå University, SE-901 87, Umeå, Sweden
| | - Hannele Tuominen
- Department of Plant Physiology, Umeå University, Umeå Plant Science Centre (UPSC), SE-901 87, Umeå, Sweden.
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25
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Duan H, Cao S, Zheng H, Hu D, Lin J, Cui B, Lin H, Hu R, Wu B, Sun Y, Li Y. Genetic Characterization of Chinese fir from Six Provinces in Southern China and Construction of a Core Collection. Sci Rep 2017; 7:13814. [PMID: 29062029 PMCID: PMC5653812 DOI: 10.1038/s41598-017-13219-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 09/20/2017] [Indexed: 12/03/2022] Open
Abstract
Large ex situ germplasm collections of plants generally contain significant diversity. A set of 700 well-conserved Chinese fir (Cunninghamia lanceolata (Lamb.) Hook) clones from six provinces in southern China in the ex situ gene bank of Longshan State Forest, was analyzed using 21 simple sequence repeat markers, with the aim of assessing the genetic diversity of these germplasm resources. Genetic analysis revealed extensive genetic variation among the accessions, with an average of 8.31 alleles per locus and a mean Shannon index of 1.331. Excluding loci with null alleles, we obtained a low level of genetic differentiation among provinces, consistent with the interpopulation genetic variation (1%). Three clusters were identified by STRUCTURE, which did not match the individuals’ geographical provenances. Ten traits related to growth and wood properties were quantified in these individuals, and there was substantial variation in all traits across individuals, these provide a potential source of variation for genetic improvement of the Chinese fir. Screening large collections for multiple-trait selective breeding programs is laborious and expensive; a core collection of 300 accessions, representative of the germplasm, was established, based on genotypic and phenotypic data. The identified small, but diverse, collections will be useful for further genome-wide association studies.
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Affiliation(s)
- Hongjing Duan
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design. National Engineering Laboratory for Tree Breeding, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, 100083, Beijing, People's Republic of China
| | - Sen Cao
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design. National Engineering Laboratory for Tree Breeding, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, 100083, Beijing, People's Republic of China
| | - Huiquan Zheng
- Guangdong Provincial Key Laboratory of Bio-control for the Forest Disease and Pest, Guangdong Academy of Forestry, 510520, Guangzhou, People's Republic of China
| | - Dehuo Hu
- Guangdong Provincial Key Laboratory of Bio-control for the Forest Disease and Pest, Guangdong Academy of Forestry, 510520, Guangzhou, People's Republic of China
| | - Jun Lin
- The ex situ gene bank of Longshan State Forest Farm, 512221, Guangzhou, Guangdong Province, People's Republic of China
| | - Binbin Cui
- Department of Biochemistry, Baoding University, 071000, Baoding, Hebei Province, People's Republic of China
| | - Huazhong Lin
- Fujian Jiangle State-owned Forestry Farm, Fujian, 353300, China
| | - Ruiyang Hu
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design. National Engineering Laboratory for Tree Breeding, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, 100083, Beijing, People's Republic of China
| | - Bo Wu
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design. National Engineering Laboratory for Tree Breeding, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, 100083, Beijing, People's Republic of China
| | - Yuhan Sun
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design. National Engineering Laboratory for Tree Breeding, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, 100083, Beijing, People's Republic of China
| | - Yun Li
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design. National Engineering Laboratory for Tree Breeding, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, 100083, Beijing, People's Republic of China.
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26
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McKown AD, Klápště J, Guy RD, Soolanayakanahally RY, La Mantia J, Porth I, Skyba O, Unda F, Douglas CJ, El-Kassaby YA, Hamelin RC, Mansfield SD, Cronk QCB. Sexual homomorphism in dioecious trees: extensive tests fail to detect sexual dimorphism in Populus †. Sci Rep 2017; 7:1831. [PMID: 28500332 PMCID: PMC5431824 DOI: 10.1038/s41598-017-01893-z] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Accepted: 04/05/2017] [Indexed: 11/09/2022] Open
Abstract
The evolution of sexual dimorphism and expansion of sex chromosomes are both driven through sexual conflict, arising from differing fitness optima between males and females. Here, we pair work in poplar (Populus) describing one of the smallest sex-determining regions known thus far in complex eukaryotes (~100 kbp) with comprehensive tests for sexual dimorphism using >1300 individuals from two Populus species and assessing 96 non-reproductive functional traits. Against expectation, we found sexual homomorphism (no non-reproductive trait differences between the sexes), suggesting that gender is functionally neutral with respect to non-reproductive features that affect plant survival and fitness. Combined with a small sex-determining region, we infer that sexual conflict may be effectively stymied or non-existent within these taxa. Both sexual homomorphism and the small sex-determining region occur against a background of strong environmental selection and local adaptation in Populus. This presents a powerful hypothesis for the evolution of dioecious species. Here, we suggest that environmental selection may be sufficient to suppress and stymy sexual conflict if it acts orthogonal to sexual selection, thereby placing limitations on the evolution of sexual dimorphism and genomic expansion of sex chromosomes.
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Affiliation(s)
- Athena D McKown
- Department of Forest and Conservation Sciences, Faculty of Forestry, University of British Columbia, Forest Sciences Centre, Vancouver, BC V6T 1Z4, Canada.
| | - Jaroslav Klápště
- Department of Dendrology and Forest Tree Breeding, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences, Prague, 165 21, Czech Republic.,Scion (New Zealand Forest Research Institute Ltd.), Whakarewarewa, Rotorua, 3046, New Zealand
| | - Robert D Guy
- Department of Forest and Conservation Sciences, Faculty of Forestry, University of British Columbia, Forest Sciences Centre, Vancouver, BC V6T 1Z4, Canada
| | - Raju Y Soolanayakanahally
- Saskatoon Research and Development Centre, Agriculture and Agri-Food Canada, Saskatoon, SK, S7N 0X2, Canada
| | - Jonathan La Mantia
- United States Department of Agriculture-Agricultural Research Service (USDA-ARS), Corn and Soybean Research, Wooster, OH, 44691, USA
| | - Ilga Porth
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Forest Sciences Centre, Vancouver, BC V6T 1Z4, Canada.,Département des sciences du bois et de la forêt, Faculté de foresterie, de géographie et de géomatique, Université Laval, Québec, QC G1V 0A6, Canada
| | - Oleksandr Skyba
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Forest Sciences Centre, Vancouver, BC V6T 1Z4, Canada
| | - Faride Unda
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Forest Sciences Centre, Vancouver, BC V6T 1Z4, Canada
| | - Carl J Douglas
- Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Yousry A El-Kassaby
- Department of Forest and Conservation Sciences, Faculty of Forestry, University of British Columbia, Forest Sciences Centre, Vancouver, BC V6T 1Z4, Canada
| | - Richard C Hamelin
- Department of Forest and Conservation Sciences, Faculty of Forestry, University of British Columbia, Forest Sciences Centre, Vancouver, BC V6T 1Z4, Canada
| | - Shawn D Mansfield
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Forest Sciences Centre, Vancouver, BC V6T 1Z4, Canada
| | - Quentin C B Cronk
- Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
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27
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Single-Step BLUP with Varying Genotyping Effort in Open-Pollinated Picea glauca. G3-GENES GENOMES GENETICS 2017; 7:935-942. [PMID: 28122953 PMCID: PMC5345723 DOI: 10.1534/g3.116.037895] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Maximization of genetic gain in forest tree breeding programs is contingent on the accuracy of the predicted breeding values and precision of the estimated genetic parameters. We investigated the effect of the combined use of contemporary pedigree information and genomic relatedness estimates on the accuracy of predicted breeding values and precision of estimated genetic parameters, as well as rankings of selection candidates, using single-step genomic evaluation (HBLUP). In this study, two traits with diverse heritabilities [tree height (HT) and wood density (WD)] were assessed at various levels of family genotyping efforts (0, 25, 50, 75, and 100%) from a population of white spruce (Picea glauca) consisting of 1694 trees from 214 open-pollinated families, representing 43 provenances in Québec, Canada. The results revealed that HBLUP bivariate analysis is effective in reducing the known bias in heritability estimates of open-pollinated populations, as it exposes hidden relatedness, potential pedigree errors, and inbreeding. The addition of genomic information in the analysis considerably improved the accuracy in breeding value estimates by accounting for both Mendelian sampling and historical coancestry that were not captured by the contemporary pedigree alone. Increasing family genotyping efforts were associated with continuous improvement in model fit, precision of genetic parameters, and breeding value accuracy. Yet, improvements were observed even at minimal genotyping effort, indicating that even modest genotyping effort is effective in improving genetic evaluation. The combined utilization of both pedigree and genomic information may be a cost-effective approach to increase the accuracy of breeding values in forest tree breeding programs where shallow pedigrees and large testing populations are the norm.
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28
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Gong C, Du Q, Xie J, Quan M, Chen B, Zhang D. Dissection of Insertion-Deletion Variants within Differentially Expressed Genes Involved in Wood Formation in Populus. FRONTIERS IN PLANT SCIENCE 2017; 8:2199. [PMID: 29403506 PMCID: PMC5778123 DOI: 10.3389/fpls.2017.02199] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 12/14/2017] [Indexed: 05/02/2023]
Abstract
Short insertions and deletions (InDels) are one of the major genetic variants and are distributed widely across the genome; however, few investigations of InDels have been conducted in long-lived perennial plants. Here, we employed a combination of RNA-seq and population resequencing to identify InDels within differentially expressed (DE) genes underlying wood formation in a natural population of Populus tomentosa (435 individuals) and utilized InDel-based association mapping to detect the causal variants under additive, dominance, and epistasis underlying growth and wood properties. In the present paper, 5,482 InDels detected from 629 DE genes showed uneven distributions throughout all 19 chromosomes, and 95.9% of these loci were diallelic InDels. Seventy-four InDels (positive false discovery rate q ≤ 0.10) from 68 genes exhibited significant additive/dominant effects on 10 growth and wood-properties, with an average of 14.7% phenotypic variance explained. Potential pleiotropy was observed in one-third of the InDels (representing 24 genes). Seven genes exhibited significantly differential expression among the genotypic classes of associated InDels, indicating possible important roles for these InDels. Epistasis analysis showed that overlapping interacting genes formed unique interconnected networks for each trait, supporting the putative biochemical links that control quantitative traits. Therefore, the identification and utilization of InDels in trees will be recognized as an effective marker system for molecular marker-assisted breeding applications, and further facilitate our understanding of quantitative genomics.
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Affiliation(s)
- Chenrui Gong
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
- College of Forestry, Henan Agricultural University, Zhengzhou, China
| | - Qingzhang Du
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, China
| | - Jianbo Xie
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
| | - Mingyang Quan
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
| | - Beibei Chen
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
| | - Deqiang Zhang
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
- *Correspondence: Deqiang Zhang,
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29
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Johnson AM, Kim H, Ralph J, Mansfield SD. Natural acetylation impacts carbohydrate recovery during deconstruction of Populus trichocarpa wood. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:48. [PMID: 28250816 PMCID: PMC5322675 DOI: 10.1186/s13068-017-0734-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Accepted: 02/14/2017] [Indexed: 05/05/2023]
Abstract
BACKGROUND Significant variation in the inherent degree of acetylation naturally exists in the xylem cell walls of Populus trichocarpa. During pretreatment, endogenous acetate hydrolyzes to acetic acid that can subsequently catalyze the breakdown of poplar wood, increasing the efficiency of biomass pretreatment. RESULTS Poplar genotypes varying in cell wall composition were pretreated in 0.3% H2SO4 in non-isothermal batch reactors. Acetic acid released from the wood was positively related to sugar release during pretreatment (R ≥ 0.9), and inversely proportional to the lignin content of the poplar wood (R = 0.6). CONCLUSION There is significant variation in wood chemistry among P. trichocarpa genotypes. This study elucidated patterns of cell wall deconstruction and clearly links carbohydrate solubilization to acetate release. Tailoring biomass feedstocks for acetate release could enhance pretreatment efficiencies.
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Affiliation(s)
- Amanda M. Johnson
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC Canada
| | - Hoon Kim
- Department of Biochemistry, University of Wisconsin, Madison, WI USA
- Department of Energy Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, Madison, WI USA
| | - John Ralph
- Department of Biochemistry, University of Wisconsin, Madison, WI USA
- Department of Energy Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, Madison, WI USA
| | - Shawn D. Mansfield
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC Canada
- Department of Energy Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, Madison, WI USA
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30
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Gene Expression Patterns of Wood Decay Fungi Postia placenta and Phanerochaete chrysosporium Are Influenced by Wood Substrate Composition during Degradation. Appl Environ Microbiol 2016; 82:4387-4400. [PMID: 27208101 DOI: 10.1128/aem.00134-16] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 05/08/2016] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Identification of the specific genes and enzymes involved in the fungal degradation of lignocellulosic biomass derived from feedstocks with various compositions is essential to the development of improved bioenergy processes. In order to elucidate the effect of substrate composition on gene expression in wood-rotting fungi, we employed microarrays based on the annotated genomes of the brown- and white-rot fungi, Rhodonia placenta (formerly Postia placenta) and Phanerochaete chrysosporium, respectively. We monitored the expression of genes involved in the enzymatic deconstruction of the cell walls of three 4-year-old Populus trichocarpa (poplar) trees of genotypes with distinct cell wall chemistries, selected from a population of several hundred trees grown in a common garden. The woody substrates were incubated with wood decay fungi for 10, 20, and 30 days. An analysis of transcript abundance in all pairwise comparisons highlighted 64 and 84 differentially expressed genes (>2-fold, P < 0.05) in P. chrysosporium and P. placenta, respectively. Cross-fungal comparisons also revealed an array of highly differentially expressed genes (>4-fold, P < 0.01) across different substrates and time points. These results clearly demonstrate that gene expression profiles of P. chrysosporium and P. placenta are influenced by wood substrate composition and the duration of incubation. Many of the significantly expressed genes encode "proteins of unknown function," and determining their role in lignocellulose degradation presents opportunities and challenges for future research. IMPORTANCE This study describes the variation in expression patterns of two wood-degrading fungi (brown- and white-rot fungi) during colonization and incubation on three different naturally occurring poplar substrates of differing chemical compositions, over time. The results clearly show that the two fungi respond differentially to their substrates and that several known and, more interestingly, currently unknown genes are highly misregulated in response to various substrate compositions. These findings highlight the need to characterize several unknown proteins for catalytic function but also as potential candidate proteins to improve the efficiency of enzymatic cocktails to degrade lignocellulosic substrates in industrial applications, such as in a biochemically based bioenergy platform.
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31
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Xie J, Tian J, Du Q, Chen J, Li Y, Yang X, Li B, Zhang D. Association genetics and transcriptome analysis reveal a gibberellin-responsive pathway involved in regulating photosynthesis. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:3325-38. [PMID: 27091876 DOI: 10.1093/jxb/erw151] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Gibberellins (GAs) regulate a wide range of important processes in plant growth and development, including photosynthesis. However, the mechanism by which GAs regulate photosynthesis remains to be understood. Here, we used multi-gene association to investigate the effect of genes in the GA-responsive pathway, as constructed by RNA sequencing, on photosynthesis, growth, and wood property traits, in a population of 435 Populus tomentosa By analyzing changes in the transcriptome following GA treatment, we identified many key photosynthetic genes, in agreement with the observed increase in measurements of photosynthesis. Regulatory motif enrichment analysis revealed that 37 differentially expressed genes related to photosynthesis shared two essential GA-related cis-regulatory elements, the GA response element and the pyrimidine box. Thus, we constructed a GA-responsive pathway consisting of 47 genes involved in regulating photosynthesis, including GID1, RGA, GID2, MYBGa, and 37 photosynthetic differentially expressed genes. Single nucleotide polymorphism (SNP)-based association analysis showed that 142 SNPs, representing 40 candidate genes in this pathway, were significantly associated with photosynthesis, growth, and wood property traits. Epistasis analysis uncovered interactions between 310 SNP-SNP pairs from 37 genes in this pathway, revealing possible genetic interactions. Moreover, a structural gene-gene matrix based on a time-course of transcript abundances provided a better understanding of the multi-gene pathway affecting photosynthesis. The results imply a functional role for these genes in mediating photosynthesis, growth, and wood properties, demonstrating the potential of combining transcriptome-based regulatory pathway construction and genetic association approaches to detect the complex genetic networks underlying quantitative traits.
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Affiliation(s)
- Jianbo Xie
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China
| | - Jiaxing Tian
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China
| | - Qingzhang Du
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China
| | - Jinhui Chen
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China
| | - Ying Li
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China
| | - Xiaohui Yang
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China
| | - Bailian Li
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China Department of Forestry, North Carolina State University, Raleigh, NC 27695-8203, USA
| | - Deqiang Zhang
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China
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Tian J, Song Y, Du Q, Yang X, Ci D, Chen J, Xie J, Li B, Zhang D. Population genomic analysis of gibberellin-responsive long non-coding RNAs in Populus. JOURNAL OF EXPERIMENTAL BOTANY 2016; 67:2467-82. [PMID: 26912799 DOI: 10.1093/jxb/erw057] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Long non-coding RNAs (lncRNAs) participate in a wide range of biological processes, but lncRNAs in plants remain largely unknown; in particular, we lack a systematic identification of plant lncRNAs involved in hormone responses. Moreover, allelic variation in lncRNAs remains poorly characterized at a large scale. Here, we conducted high-throughput RNA-sequencing of leaves from control and gibberellin (GA)-treated Populus tomentosa and identified 7655 reliably expressed lncRNAs. Among the 7655 lncRNAs, the levels of 410 lncRNAs changed in response to GA. Seven GA-responsive lncRNAs were predicted to be putative targets of 18 miRNAs, and one GA-responsive lncRNA (TCONS_00264314) was predicted to be a target mimic of ptc-miR6459b. Computational analysis predicted 939 potential cis-regulated target genes and 965 potential trans-regulated target genes for GA-responsive lncRNAs. Functional annotation of these potential target genes showed that they participate in many different biological processes, including auxin signal transduction and synthesis of cellulose and pectin, indicating that GA-responsive lncRNAs may influence growth and wood properties. Finally, single nucleotide polymorphism (SNP)-based association analysis showed that 112 SNPs from 52 GA-responsive lncRNAs and 1014 SNPs from 296 potential target genes were significantly associated with growth and wood properties. Epistasis analysis also provided evidence for interactions between lncRNAs and their potential target genes. Our study provides a comprehensive view of P. tomentosa lncRNAs and offers insights into the potential functions and regulatory interactions of GA-responsive lncRNAs, thus forming the foundation for future functional analysis of GA-responsive lncRNAs in P. tomentosa.
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Affiliation(s)
- Jiaxing Tian
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, PR China Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, PR China
| | - Yuepeng Song
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, PR China Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, PR China
| | - Qingzhang Du
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, PR China Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, PR China
| | - Xiaohui Yang
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, PR China Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, PR China
| | - Dong Ci
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, PR China Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, PR China
| | - Jinhui Chen
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, PR China Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, PR China
| | - Jianbo Xie
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, PR China Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, PR China
| | - Bailian Li
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, PR China Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, PR China. Department of Forestry, North Carolina State University, Raleigh, NC 27695-8203, USA
| | - Deqiang Zhang
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, PR China Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, PR China.
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Implementation of the Realized Genomic Relationship Matrix to Open-Pollinated White Spruce Family Testing for Disentangling Additive from Nonadditive Genetic Effects. G3-GENES GENOMES GENETICS 2016; 6:743-53. [PMID: 26801647 PMCID: PMC4777135 DOI: 10.1534/g3.115.025957] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The open-pollinated (OP) family testing combines the simplest known progeny evaluation and quantitative genetics analyses as candidates’ offspring are assumed to represent independent half-sib families. The accuracy of genetic parameter estimates is often questioned as the assumption of “half-sibling” in OP families may often be violated. We compared the pedigree- vs. marker-based genetic models by analysing 22-yr height and 30-yr wood density for 214 white spruce [Picea glauca (Moench) Voss] OP families represented by 1694 individuals growing on one site in Quebec, Canada. Assuming half-sibling, the pedigree-based model was limited to estimating the additive genetic variances which, in turn, were grossly overestimated as they were confounded by very minor dominance and major additive-by-additive epistatic genetic variances. In contrast, the implemented genomic pairwise realized relationship models allowed the disentanglement of additive from all nonadditive factors through genetic variance decomposition. The marker-based models produced more realistic narrow-sense heritability estimates and, for the first time, allowed estimating the dominance and epistatic genetic variances from OP testing. In addition, the genomic models showed better prediction accuracies compared to pedigree models and were able to predict individual breeding values for new individuals from untested families, which was not possible using the pedigree-based model. Clearly, the use of marker-based relationship approach is effective in estimating the quantitative genetic parameters of complex traits even under simple and shallow pedigree structure.
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Watkins DW, de Moraes MMGA, Asbjornsen H, Mayer AS, Licata J, Lopez JG, Pypker TG, Molina VG, Marques GF, Carneiro ACG, Nuñez HM, Önal H, da Nobrega Germano B. Bioenergy Development Policy and Practice Must Recognize Potential Hydrologic Impacts: Lessons from the Americas. ENVIRONMENTAL MANAGEMENT 2015; 56:1295-1314. [PMID: 25813630 DOI: 10.1007/s00267-015-0460-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Accepted: 03/19/2015] [Indexed: 06/04/2023]
Abstract
Large-scale bioenergy production will affect the hydrologic cycle in multiple ways, including changes in canopy interception, evapotranspiration, infiltration, and the quantity and quality of surface runoff and groundwater recharge. As such, the water footprints of bioenergy sources vary significantly by type of feedstock, soil characteristics, cultivation practices, and hydro-climatic regime. Furthermore, water management implications of bioenergy production depend on existing land use, relative water availability, and competing water uses at a watershed scale. This paper reviews previous research on the water resource impacts of bioenergy production-from plot-scale hydrologic and nutrient cycling impacts to watershed and regional scale hydro-economic systems relationships. Primary gaps in knowledge that hinder policy development for integrated management of water-bioenergy systems are highlighted. Four case studies in the Americas are analyzed to illustrate relevant spatial and temporal scales for impact assessment, along with unique aspects of biofuel production compared to other agroforestry systems, such as energy-related conflicts and tradeoffs. Based on the case studies, the potential benefits of integrated resource management are assessed, as is the need for further case-specific research.
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Affiliation(s)
- David W Watkins
- Department of Civil and Environmental Engineering, Michigan Technological University, Houghton, MI, USA.
| | | | - Heidi Asbjornsen
- Department of Natural Resources and Environment, University of New Hampshire, Durham, NH, USA
| | - Alex S Mayer
- Department of Civil and Environmental Engineering, Michigan Technological University, Houghton, MI, USA
| | - Julian Licata
- Instituto Nacional de Tecnología Agropecuraria, Buenos Aires, Argentina
| | - Jose Gutierrez Lopez
- Department of Natural Resources and Environment, University of New Hampshire, Durham, NH, USA
| | - Thomas G Pypker
- Department of Natural Resource Science, Thompson Rivers University, Kamloops, BC, Canada
| | - Vivianna Gamez Molina
- Department of Civil, Environmental, and Sustainable Engineering, Arizona State University, Tempe, AZ, USA
| | - Guilherme Fernandes Marques
- Department of Civil Engineering, Instituto de Pesquisas Hidráulicas (IPH), Universidade Federal Do Rio Grande do Sul, Porto Alegre, Brazil
| | | | - Hector M Nuñez
- Department of Economics, Centro de Investigación y Docencia Económicas (CIDE), Aguascalientes, Mexico
| | - Hayri Önal
- Department of Agricultural and Consumer Economics, University of Illinois at Urbana-Champaign, Champaign, IL, USA
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Porth I, Klápště J, McKown AD, La Mantia J, Guy RD, Ingvarsson PK, Hamelin R, Mansfield SD, Ehlting J, Douglas CJ, El-Kassaby YA. Evolutionary Quantitative Genomics of Populus trichocarpa. PLoS One 2015; 10:e0142864. [PMID: 26599762 PMCID: PMC4658102 DOI: 10.1371/journal.pone.0142864] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 10/27/2015] [Indexed: 11/23/2022] Open
Abstract
Forest trees generally show high levels of local adaptation and efforts focusing on understanding adaptation to climate will be crucial for species survival and management. Here, we address fundamental questions regarding the molecular basis of adaptation in undomesticated forest tree populations to past climatic environments by employing an integrative quantitative genetics and landscape genomics approach. Using this comprehensive approach, we studied the molecular basis of climate adaptation in 433 Populus trichocarpa (black cottonwood) genotypes originating across western North America. Variation in 74 field-assessed traits (growth, ecophysiology, phenology, leaf stomata, wood, and disease resistance) was investigated for signatures of selection (comparing QST -FST) using clustering of individuals by climate of origin (temperature and precipitation). 29,354 SNPs were investigated employing three different outlier detection methods and marker-inferred relatedness was estimated to obtain the narrow-sense estimate of population differentiation in wild populations. In addition, we compared our results with previously assessed selection of candidate SNPs using the 25 topographical units (drainages) across the P. trichocarpa sampling range as population groupings. Narrow-sense QST for 53% of distinct field traits was significantly divergent from expectations of neutrality (indicating adaptive trait variation); 2,855 SNPs showed signals of diversifying selection and of these, 118 SNPs (within 81 genes) were associated with adaptive traits (based on significant QST). Many SNPs were putatively pleiotropic for functionally uncorrelated adaptive traits, such as autumn phenology, height, and disease resistance. Evolutionary quantitative genomics in P. trichocarpa provides an enhanced understanding regarding the molecular basis of climate-driven selection in forest trees and we highlight that important loci underlying adaptive trait variation also show relationship to climate of origin. We consider our approach the most comprehensive, as it uncovers the molecular mechanisms of adaptation using multiple methods and tests. We also provide a detailed outline of the required analyses for studying adaptation to the environment in a population genomics context to better understand the species’ potential adaptive capacity to future climatic scenarios.
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Affiliation(s)
- Ilga Porth
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
- Département des Sciences du Bois et de la Forêt, Faculté de Foresterie, de Géographie et de Géomatique, Université Laval, Québec, QC, G1V 0A6 Canada
| | - Jaroslav Klápště
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
- Department of Genetics and Physiology of Forest Trees, Czech University of Life Sciences, Prague, 165 21, Czech Republic
| | - Athena D. McKown
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Jonathan La Mantia
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
- Corn, Soybean and Wheat Quality Research Unit, United States Department of Agriculture, Wooster, Ohio, 44691 United States of America
| | - Robert D. Guy
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Pär K. Ingvarsson
- Department of Ecology and Environmental Science, Umeå University, Umeå, SE-901 87, Sweden
| | - Richard Hamelin
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Shawn D. Mansfield
- Department of Wood Science, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Jürgen Ehlting
- Department of Biology and Centre for Forest Biology, University of Victoria, Victoria, BC V8W 3N5, Canada
| | - Carl J. Douglas
- Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Yousry A. El-Kassaby
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
- * E-mail:
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Swamy PS, Hu H, Pattathil S, Maloney VJ, Xiao H, Xue LJ, Chung JD, Johnson VE, Zhu Y, Peter GF, Hahn MG, Mansfield SD, Harding SA, Tsai CJ. Tubulin perturbation leads to unexpected cell wall modifications and affects stomatal behaviour in Populus. JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:6507-18. [PMID: 26246616 PMCID: PMC4588895 DOI: 10.1093/jxb/erv383] [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] [Indexed: 05/03/2023]
Abstract
Cortical microtubules are integral to plant morphogenesis, cell wall synthesis, and stomatal behaviour, presumably by governing cellulose microfibril orientation. Genetic manipulation of tubulins often leads to abnormal plant development, making it difficult to probe additional roles of cortical microtubules in cell wall biogenesis. Here, it is shown that expressing post-translational C-terminal modification mimics of α-tubulin altered cell wall characteristics and guard cell dynamics in transgenic Populus tremula x alba that otherwise appear normal. 35S promoter-driven transgene expression was high in leaves but unusually low in xylem, suggesting high levels of tubulin transgene expression were not tolerated in wood-forming tissues during regeneration of transformants. Cellulose, hemicellulose, and lignin contents were unaffected in transgenic wood, but expression of cell wall-modifying enzymes, and extractability of lignin-bound pectin and xylan polysaccharides were increased in developing xylem. The results suggest that pectin and xylan polysaccharides deposited early during cell wall biogenesis are more sensitive to subtle tubulin perturbation than cellulose and matrix polysaccharides deposited later. Tubulin perturbation also affected guard cell behaviour, delaying drought-induced stomatal closure as well as light-induced stomatal opening in leaves. Pectins have been shown to confer cell wall flexibility critical for reversible stomatal movement, and results presented here are consistent with microtubule involvement in this process. Taken together, the data show the value of growth-compatible tubulin perturbations for discerning microtubule functions, and add to the growing body of evidence for microtubule involvement in non-cellulosic polysaccharide assembly during cell wall biogenesis.
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Affiliation(s)
- Prashant S Swamy
- School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA
| | - Hao Hu
- School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA Department of Genetics, University of Georgia, Athens, GA 30602, USA
| | - Sivakumar Pattathil
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA
| | - Victoria J Maloney
- Department of Wood Science, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Hui Xiao
- Laboratory for Macromolecular Analysis and Proteomics, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Liang-Jiao Xue
- School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA Department of Genetics, University of Georgia, Athens, GA 30602, USA
| | - Jeng-Der Chung
- Division of Silviculture, Taiwan Forestry Research Institute, Taipei 10066, Taiwan
| | - Virgil E Johnson
- School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA Department of Genetics, University of Georgia, Athens, GA 30602, USA
| | - Yingying Zhu
- School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA Department of Genetics, University of Georgia, Athens, GA 30602, USA
| | - Gary F Peter
- School of Forest Resources and Conservation, University of Florida, Gainesville, FL 32611, USA
| | - Michael G Hahn
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA
| | - Shawn D Mansfield
- Department of Wood Science, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Scott A Harding
- School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA Department of Genetics, University of Georgia, Athens, GA 30602, USA
| | - Chung-Jui Tsai
- School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA Department of Genetics, University of Georgia, Athens, GA 30602, USA
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Du Q, Wang L, Yang X, Gong C, Zhang D. Populus endo-β-1,4-glucanases gene family: genomic organization, phylogenetic analysis, expression profiles and association mapping. PLANTA 2015; 241:1417-34. [PMID: 25716095 DOI: 10.1007/s00425-015-2271-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2014] [Accepted: 02/19/2015] [Indexed: 05/05/2023]
Abstract
Extensive characterization of the poplar GH9 gene family provides new insights into GH9 function and evolution in woody species, and may drive novel progress for molecular breeding in trees. In higher plants, endo-β-1,4-glucanases (cellulases) belonging to the glycosyl hydrolase family 9 (GH9) have roles in cell wall synthesis, remodeling and degradation. To increase the understanding of the GH9 family in perennial woody species, we conducted an extensive characterization of the GH9 family in the model tree species, Populus. We characterized 25 putative GH9 members in Populus with three subclasses (A, B, and C), using structures and bioinformatic analysis. Phylogenetic analyses of 114 GH9s from plant (dicot, monocot, and conifer) and bacterial species (outgroup) demonstrated that plant GH9s are monophyletic with respect to bacteria GH9s. Three subclasses, A, B, and C, of plant GH9 are formed before the divergence of angiosperms and gymnosperms. Chromosomal localization and duplications of GH9s in the Populus genome showed that eight paralogous pairs remained in conserved positions on segmental duplicated blocks, suggesting duplication of chromosomal segments has contributed to the family expansion. By examining tissue-specific expression profiles for all 25 members, we found that GH9 members exhibited distinct but partially overlapping expression patterns, while certain members have higher transcript abundance in mature or developing xylem. Based on our understanding of intraspecific variation and linkage disequilibrium of two KORRIGANs (PtoKOR1 and PtoKOR2) in natural population of Populus tomentosa, two non-synonymous SNPs in PtoKOR1 associated with fiber width and holocellulose content were obtained. Characterizations of the poplar GH9 family provide new insights into GH9 function and evolution in woody species, and may drive novel progress for molecular breeding in trees.
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Affiliation(s)
- Qingzhang Du
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, People's Republic of China,
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Allelic Variation in Cinnamyl Alcohol Dehydrogenase (LoCAD) Associated with Wood Properties of Larix olgensis. FORESTS 2015. [DOI: 10.3390/f6051649] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Variation in the Growth Traits and Wood Properties of Hybrid White Poplar Clones. FORESTS 2015. [DOI: 10.3390/f6041107] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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40
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Porth I, El-Kassaby YA. Using Populus as a lignocellulosic feedstock for bioethanol. Biotechnol J 2015; 10:510-24. [PMID: 25676392 DOI: 10.1002/biot.201400194] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Revised: 11/11/2014] [Accepted: 12/30/2014] [Indexed: 11/10/2022]
Abstract
Populus species along with species from the sister genus Salix will provide valuable feedstock resources for advanced second-generation biofuels. Their inherent fast growth characteristics can particularly be exploited for short rotation management, a time and energy saving cultivation alternative for lignocellulosic feedstock supply. Salicaceae possess inherent cell wall characteristics with favorable cellulose to lignin ratios for utilization as bioethanol crop. We review economically important traits relevant for intensively managed biofuel crop plantations, genomic and phenotypic resources available for Populus, breeding strategies for forest trees dedicated to bioenergy provision, and bioprocesses and downstream applications related to opportunities using Salicaceae as a renewable resource. Challenges need to be resolved for every single step of the conversion process chain, i.e., starting from tree domestication for improved performance as a bioenergy crop, bioconversion process, policy development for land use changes associated with advanced biofuels, and harvest and supply logistics associated with industrial-scale biorefinery plants using Populus as feedstock. Significant hurdles towards cost and energy efficiency, environmental friendliness, and yield maximization with regards to biomass pretreatment, saccharification, and fermentation of celluloses and the sustainability of biorefineries as a whole still need to be overcome.
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Affiliation(s)
- Ilga Porth
- Forest and Conservation Sciences, University of British Columbia, Vancouver, Canada.
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41
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Muchero W, Guo J, DiFazio SP, Chen JG, Ranjan P, Slavov GT, Gunter LE, Jawdy S, Bryan AC, Sykes R, Ziebell A, Klápště J, Porth I, Skyba O, Unda F, El-Kassaby YA, Douglas CJ, Mansfield SD, Martin J, Schackwitz W, Evans LM, Czarnecki O, Tuskan GA. High-resolution genetic mapping of allelic variants associated with cell wall chemistry in Populus. BMC Genomics 2015; 16:24. [PMID: 25613058 PMCID: PMC4307895 DOI: 10.1186/s12864-015-1215-z] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2014] [Accepted: 01/02/2015] [Indexed: 11/13/2022] Open
Abstract
Background QTL cloning for the discovery of genes underlying polygenic traits has historically been cumbersome in long-lived perennial plants like Populus. Linkage disequilibrium-based association mapping has been proposed as a cloning tool, and recent advances in high-throughput genotyping and whole-genome resequencing enable marker saturation to levels sufficient for association mapping with no a priori candidate gene selection. Here, multiyear and multienvironment evaluation of cell wall phenotypes was conducted in an interspecific P. trichocarpa x P. deltoides pseudo-backcross mapping pedigree and two partially overlapping populations of unrelated P. trichocarpa genotypes using pyrolysis molecular beam mass spectrometry, saccharification, and/ or traditional wet chemistry. QTL mapping was conducted using a high-density genetic map with 3,568 SNP markers. As a fine-mapping approach, chromosome-wide association mapping targeting a QTL hot-spot on linkage group XIV was performed in the two P. trichocarpa populations. Both populations were genotyped using the 34 K Populus Infinium SNP array and whole-genome resequencing of one of the populations facilitated marker-saturation of candidate intervals for gene identification. Results Five QTLs ranging in size from 0.6 to 1.8 Mb were mapped on linkage group XIV for lignin content, syringyl to guaiacyl (S/G) ratio, 5- and 6-carbon sugars using the mapping pedigree. Six candidate loci exhibiting significant associations with phenotypes were identified within QTL intervals. These associations were reproducible across multiple environments, two independent genotyping platforms, and different plant growth stages. cDNA sequencing for allelic variants of three of the six loci identified polymorphisms leading to variable length poly glutamine (PolyQ) stretch in a transcription factor annotated as an ANGUSTIFOLIA C-terminus Binding Protein (CtBP) and premature stop codons in a KANADI transcription factor as well as a protein kinase. Results from protoplast transient expression assays suggested that each of the polymorphisms conferred allelic differences in the activation of cellulose, hemicelluloses, and lignin pathway marker genes. Conclusion This study illustrates the utility of complementary QTL and association mapping as tools for gene discovery with no a priori candidate gene selection. This proof of concept in a perennial organism opens up opportunities for discovery of novel genetic determinants of economically important but complex traits in plants. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-1215-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Wellington Muchero
- BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
| | - Jianjun Guo
- BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA. .,Current address: Department of Plant Biology, Carnegie Institute for Science, Stanford, CA, 94305, USA.
| | - Stephen P DiFazio
- Department of Biology, West Virginia University, Morgantown, WV, 26506, USA.
| | - Jin-Gui Chen
- BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
| | - Priya Ranjan
- BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
| | - Gancho T Slavov
- Institute of Biological, Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, SY23 3EB, UK.
| | - Lee E Gunter
- BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
| | - Sara Jawdy
- BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
| | - Anthony C Bryan
- BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
| | - Robert Sykes
- Bioscience Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO 80401, USA.
| | - Angela Ziebell
- Bioscience Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO 80401, USA.
| | - Jaroslav Klápště
- Department of Forest and Conservation Sciences, Faculty of Forestry, University of British Columbia, Forest Sciences Centre, 2424 Main Mall, Vancouver, BC, V6T 1Z4, Canada. .,Department of Genetics and Physiology of Forest Trees, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences in Prague, Kamýcká 129, 165 21, Praha 6, Czech Republic.
| | - Ilga Porth
- Department of Forest and Conservation Sciences, Faculty of Forestry, University of British Columbia, Forest Sciences Centre, 2424 Main Mall, Vancouver, BC, V6T 1Z4, Canada.
| | - Oleksandr Skyba
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Forest Sciences Centre, 2424 Main Mall, Vancouver, BC, V6T 1Z4, Canada.
| | - Faride Unda
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Forest Sciences Centre, 2424 Main Mall, Vancouver, BC, V6T 1Z4, Canada.
| | - Yousry A El-Kassaby
- Department of Forest and Conservation Sciences, Faculty of Forestry, University of British Columbia, Forest Sciences Centre, 2424 Main Mall, Vancouver, BC, V6T 1Z4, Canada.
| | - 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, 2424 Main Mall, Vancouver, BC, V6T 1Z4, Canada.
| | - Joel Martin
- U.S. Department of Energy Joint Genome Institute, Walnut Creek, CA, 94598, USA.
| | - Wendy Schackwitz
- U.S. Department of Energy Joint Genome Institute, Walnut Creek, CA, 94598, USA.
| | - Luke M Evans
- Department of Biology, West Virginia University, Morgantown, WV, 26506, USA.
| | - Olaf Czarnecki
- BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
| | - Gerald A Tuskan
- BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
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42
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Verlinden MS, Fichot R, Broeckx LS, Vanholme B, Boerjan W, Ceulemans R. Carbon isotope compositions (δ(13) C) of leaf, wood and holocellulose differ among genotypes of poplar and between previous land uses in a short-rotation biomass plantation. PLANT, CELL & ENVIRONMENT 2015; 38:144-156. [PMID: 24906162 DOI: 10.1111/pce.12383] [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: 10/29/2013] [Revised: 05/26/2014] [Accepted: 05/27/2014] [Indexed: 06/03/2023]
Abstract
The efficiency of water use to produce biomass is a key trait in designing sustainable bioenergy-devoted systems. We characterized variations in the carbon isotope composition (δ(13) C) of leaves, current year wood and holocellulose (as proxies for water use efficiency, WUE) among six poplar genotypes in a short-rotation plantation. Values of δ(13) Cwood and δ(13) Cholocellulose were tightly and positively correlated, but the offset varied significantly among genotypes (0.79-1.01‰). Leaf phenology was strongly correlated with δ(13) C, and genotypes with a longer growing season showed a higher WUE. In contrast, traits related to growth and carbon uptake were poorly linked to δ(13) C. Trees growing on former pasture with higher N-availability displayed higher δ(13) C as compared with trees growing on former cropland. The positive relationships between δ(13) Cleaf and leaf N suggested that spatial variations in WUE over the plantation were mainly driven by an N-related effect on photosynthetic capacities. The very coherent genotype ranking obtained with δ(13) C in the different tree compartments has some practical outreach. Because WUE remains largely uncoupled from growth in poplar plantations, there is potential to identify genotypes with satisfactory growth and higher WUE.
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Affiliation(s)
- M S Verlinden
- Department of Biology, Research Group of Plant and Vegetation Ecology, University of Antwerp, Wilrijk, B-2610, Belgium
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43
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Xu B, Tian J, Du Q, Gong C, Pan W, Zhang D. Single nucleotide polymorphisms in a cellulose synthase gene (PtoCesA3) are associated with growth and wood properties in Populus tomentosa. PLANTA 2014; 240:1269-86. [PMID: 25143249 DOI: 10.1007/s00425-014-2149-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Accepted: 08/08/2014] [Indexed: 05/21/2023]
Abstract
In plants, the composition and organization of the cell wall determine cell shape, enable cell expansion, and affect the properties of woody tissues. Cellulose synthase (CesA) genes encode the enzymes involved in the synthesis of cellulose which is the major component of plant primary and secondary cell walls. Here, we isolated a full-length PtoCesA3 cDNA from the stem cambium tissue of Populus tomentosa. Tissue-specific expression profiling showed that PtoCesA3 is highly expressed during primary cell wall formation. Estimation of single nucleotide polymorphism (SNP) diversity and linkage disequilibrium (LD) revealed that PtoCesA3 harbors high SNP diversity (π(T) = 0.00995 and θ(w) = 0.0102) and low LD (r(2) ≥ 0.1, within 1,280 bp). Association analysis in a P. tomentosa association population (460 individuals) showed that seven SNPs (false discovery rate Q < 0.10) and five haplotypes (Q < 0.10) were significantly associated with growth and wood properties, explaining 4.09-7.02% of the phenotypic variance. All significant marker-trait associations were validated in at least one of the three smaller subsets (climatic regions) while five associations were repeated in the linkage population. Variation in RNA transcript abundance among genotypic classes of significant loci was also confirmed in the association or linkage populations. Identification of PtoCesA3 and examining its allelic polymorphisms using association studies open an avenue to understand the mechanism of cellulose synthesis in the primary cell wall and its effects on the properties of woody tissues.
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Affiliation(s)
- Baohua Xu
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, People's Republic of China
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44
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Chen D, Neumann K, Friedel S, Kilian B, Chen M, Altmann T, Klukas C. Dissecting the phenotypic components of crop plant growth and drought responses based on high-throughput image analysis. THE PLANT CELL 2014; 26:4636-55. [PMID: 25501589 PMCID: PMC4311194 DOI: 10.1105/tpc.114.129601] [Citation(s) in RCA: 178] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Revised: 11/20/2014] [Accepted: 11/21/2014] [Indexed: 05/18/2023]
Abstract
Significantly improved crop varieties are urgently needed to feed the rapidly growing human population under changing climates. While genome sequence information and excellent genomic tools are in place for major crop species, the systematic quantification of phenotypic traits or components thereof in a high-throughput fashion remains an enormous challenge. In order to help bridge the genotype to phenotype gap, we developed a comprehensive framework for high-throughput phenotype data analysis in plants, which enables the extraction of an extensive list of phenotypic traits from nondestructive plant imaging over time. As a proof of concept, we investigated the phenotypic components of the drought responses of 18 different barley (Hordeum vulgare) cultivars during vegetative growth. We analyzed dynamic properties of trait expression over growth time based on 54 representative phenotypic features. The data are highly valuable to understand plant development and to further quantify growth and crop performance features. We tested various growth models to predict plant biomass accumulation and identified several relevant parameters that support biological interpretation of plant growth and stress tolerance. These image-based traits and model-derived parameters are promising for subsequent genetic mapping to uncover the genetic basis of complex agronomic traits. Taken together, we anticipate that the analytical framework and analysis results presented here will be useful to advance our views of phenotypic trait components underlying plant development and their responses to environmental cues.
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Affiliation(s)
- Dijun Chen
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), D-06466 Gatersleben, Germany Department of Bioinformatics, College of Life Sciences, Zhejiang University, Hangzhou 310058, P.R. China
| | - Kerstin Neumann
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), D-06466 Gatersleben, Germany
| | - Swetlana Friedel
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), D-06466 Gatersleben, Germany
| | - Benjamin Kilian
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), D-06466 Gatersleben, Germany
| | - Ming Chen
- Department of Bioinformatics, College of Life Sciences, Zhejiang University, Hangzhou 310058, P.R. China
| | - Thomas Altmann
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), D-06466 Gatersleben, Germany
| | - Christian Klukas
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), D-06466 Gatersleben, Germany
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Geraldes A, Farzaneh N, Grassa CJ, McKown AD, Guy RD, Mansfield SD, Douglas CJ, Cronk QCB. Landscape genomics of Populus trichocarpa: the role of hybridization, limited gene flow, and natural selection in shaping patterns of population structure. Evolution 2014; 68:3260-80. [PMID: 25065449 DOI: 10.1111/evo.12497] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Accepted: 07/08/2014] [Indexed: 01/17/2023]
Abstract
Populus trichocarpa is an ecologically important tree across western North America. We used a large population sample of 498 accessions over a wide geographical area genotyped with a 34K Populus SNP array to quantify geographical patterns of genetic variation in this species (landscape genomics). We present evidence that three processes contribute to the observed patterns: (1) introgression from the sister species P. balsamifera, (2) isolation by distance (IBD), and (3) natural selection. Introgression was detected only at the margins of the species' distribution. IBD was significant across the sampled area as a whole, but no evidence of restricted gene flow was detected in a core of drainages from southern British Columbia (BC). We identified a large number of FST outliers. Gene Ontology analyses revealed that FST outliers are overrepresented in genes involved in circadian rhythm and response to red/far-red light when the entire dataset is considered, whereas in southern BC heat response genes are overrepresented. We also identified strong correlations between geoclimate variables and allele frequencies at FST outlier loci that provide clues regarding the selective pressures acting at these loci.
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Affiliation(s)
- Armando Geraldes
- Department of Botany, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada.
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McKown AD, Klápště J, Guy RD, Geraldes A, Porth I, Hannemann J, Friedmann M, Muchero W, Tuskan GA, Ehlting J, Cronk QCB, El-Kassaby YA, Mansfield SD, Douglas CJ. Genome-wide association implicates numerous genes underlying ecological trait variation in natural populations of Populus trichocarpa. THE NEW PHYTOLOGIST 2014; 203:535-553. [PMID: 24750093 DOI: 10.1111/nph.12815] [Citation(s) in RCA: 110] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Accepted: 03/14/2014] [Indexed: 05/02/2023]
Abstract
In order to uncover the genetic basis of phenotypic trait variation, we used 448 unrelated wild accessions of black cottonwood (Populus trichocarpa) from much of its range in western North America. Extensive data from large-scale trait phenotyping (with spatial and temporal replications within a common garden) and genotyping (with a 34 K Populus single nucleotide polymorphism (SNP) array) of all accessions were used for gene discovery in a genome-wide association study (GWAS). We performed GWAS with 40 biomass, ecophysiology and phenology traits and 29,355 filtered SNPs representing 3518 genes. The association analyses were carried out using a Unified Mixed Model accounting for population structure effects among accessions. We uncovered 410 significant SNPs using a Bonferroni-corrected threshold (P<1.7×10(-6)). Markers were found across 19 chromosomes, explained 1-13% of trait variation, and implicated 275 unique genes in trait associations. Phenology had the largest number of associated genes (240 genes), followed by biomass (53 genes) and ecophysiology traits (25 genes). The GWAS results propose numerous loci for further investigation. Many traits had significant associations with multiple genes, underscoring their genetic complexity. Genes were also identified with multiple trait associations within and/or across trait categories. In some cases, traits were genetically correlated while in others they were not.
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Affiliation(s)
- Athena D McKown
- Department of Forest and Conservation Sciences, Faculty of Forestry, University of British Columbia, Forest Sciences Centre, 2424 Main Mall, Vancouver, BC, V6T 1Z4, Canada
| | - Jaroslav Klápště
- Department of Forest and Conservation Sciences, Faculty of Forestry, University of British Columbia, Forest Sciences Centre, 2424 Main Mall, Vancouver, BC, V6T 1Z4, Canada
- Department of Dendrology and Forest Tree Breeding, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences, Prague, 165 21, Czech Republic
| | - Robert D Guy
- Department of Forest and Conservation Sciences, Faculty of Forestry, University of British Columbia, Forest Sciences Centre, 2424 Main Mall, Vancouver, BC, V6T 1Z4, Canada
| | - Armando Geraldes
- Department of Botany, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Ilga Porth
- Department of Forest and Conservation Sciences, Faculty of Forestry, University of British Columbia, Forest Sciences Centre, 2424 Main Mall, Vancouver, BC, V6T 1Z4, Canada
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Forest Sciences Centre, 2424 Main Mall, Vancouver, BC, V6T 1Z4, Canada
| | - Jan Hannemann
- Department of Biology and Centre for Forest Biology, University of Victoria, Victoria, BC, V8W 3N5, Canada
| | - Michael Friedmann
- Department of Botany, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Wellington Muchero
- 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
| | - Jürgen Ehlting
- Department of Biology and Centre for Forest Biology, University of Victoria, Victoria, BC, V8W 3N5, Canada
| | - Quentin C B Cronk
- Department of Botany, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Yousry A El-Kassaby
- Department of Forest and Conservation Sciences, Faculty of Forestry, University of British Columbia, Forest Sciences Centre, 2424 Main Mall, Vancouver, BC, V6T 1Z4, Canada
| | - Shawn D Mansfield
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Forest Sciences Centre, 2424 Main Mall, Vancouver, BC, V6T 1Z4, Canada
| | - Carl J Douglas
- Department of Botany, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
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Ragauskas AJ, Beckham GT, Biddy MJ, Chandra R, Chen F, Davis MF, Davison BH, Dixon RA, Gilna P, Keller M, Langan P, Naskar AK, Saddler JN, Tschaplinski TJ, Tuskan GA, Wyman CE. Lignin Valorization: Improving Lignin Processing in the Biorefinery. Science 2014; 344:1246843. [DOI: 10.1126/science.1246843] [Citation(s) in RCA: 2410] [Impact Index Per Article: 241.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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48
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Tian J, Chang M, Du Q, Xu B, Zhang D. Single-nucleotide polymorphisms in PtoCesA7 and their association with growth and wood properties in Populus tomentosa. Mol Genet Genomics 2014; 289:439-55. [PMID: 24549852 DOI: 10.1007/s00438-014-0824-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Accepted: 02/04/2014] [Indexed: 12/30/2022]
Abstract
Cellulose synthase (CesA) genes encode the enzymes that synthesize cellulose; therefore, CesAs play central roles in plant development and affect the yield and quality of wood, essential properties for industrial applications of plant biomass. To effectively manipulate wood biosynthesis in trees and improve wood quality, we thus require a better understanding of the natural variation in CesAs. Association studies have emerged as a powerful tool for identification of variation associated with quantitative traits. Here, we used a candidate gene-based association mapping approach to identify PtoCesA7 allelic variants that associate with growth and wood quality traits in Populus tomentosa. We isolated a full-length PtoCesA7 cDNA and observed high PtoCesA7 expression in xylem, consistent with the xylem-specific expression of CesA7. Nucleotide diversity and linkage disequilibrium (LD) in PtoCesA7, sampled from the P. tomentosa natural distribution, revealed that PtoCesA7 harbors high nucleotide diversity (π(T) = 0.0091) and low LD (r(2) ≥ 0.1, within 800 bp). By association analysis, we identified seven single-nucleotide polymorphisms (SNPs) (false discovery rate Q < 0.10) and 12 haplotypes (Q < 0.10) that associated with growth and wood properties, explaining 3.62-10.59 % of the phenotypic variance. We also validated 9 of the 10 significant marker-trait associations in at least one of three smaller subsets (climatic regions) or in a linkage-mapping population. Thus, our study identified functional PtoCesA7 allelic variants associated with growth and wood quality traits, giving new insights into genes affecting wood quality and quantity. From an applied perspective, the SNPs revealed in this study have potential applications in marker-assisted breeding.
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Affiliation(s)
- Jiaxing Tian
- National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, People's Republic of China
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49
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Porth I, Klápště J, McKown AD, La Mantia J, Hamelin RC, Skyba O, Unda F, Friedmann MC, Cronk QC, Ehlting J, Guy RD, Mansfield SD, El-Kassaby YA, Douglas CJ. Extensive functional pleiotropy of REVOLUTA substantiated through forward genetics. PLANT PHYSIOLOGY 2014; 164:548-54. [PMID: 24309192 PMCID: PMC3912088 DOI: 10.1104/pp.113.228783] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
In plants, genes may sustain extensive pleiotropic functional properties by individually affecting multiple, distinct traits. We discuss results from three genome-wide association studies of approximately 400 natural poplar (Populus trichocarpa) accessions phenotyped for 60 ecological/biomass, wood quality, and rust fungus resistance traits. Single-nucleotide polymorphisms (SNPs) in the poplar ortholog of the class III homeodomain-leucine zipper transcription factor gene REVOLUTA (PtREV) were significantly associated with three specific traits. Based on SNP associations with fungal resistance, leaf drop, and cellulose content, the PtREV gene contains three potential regulatory sites within noncoding regions at the gene's 3' end, where alternative splicing and messenger RNA processing actively occur. The polymorphisms in this region associated with leaf abscission and cellulose content are suggested to represent more recent variants, whereas the SNP associated with leaf rust resistance may be more ancient, consistent with REV's primary role in auxin signaling and its functional evolution in supporting fundamental processes of vascular plant development.
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50
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