The Experts below are selected from a list of 13605 Experts worldwide ranked by ideXlab platform
Richard J. Murphy - One of the best experts on this subject based on the ideXlab platform.
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X-ray micro-computed tomography in willow reveals tissue patterning of Reaction Wood and delay in programmed cell death
BMC plant biology, 2015Co-Authors: Nicholas J. B. Brereton, Michael J. Ray, Ian Shield, Angela Karp, Farah Ahmed, Dan Sykes, Richard J. MurphyAbstract:Background Variation in the Reaction Wood (RW) response has been shown to be a principle component driving differences in lignocellulosic sugar yield from the bioenergy crop willow. The phenotypic cause(s) behind these differences in sugar yield, beyond their common elicitor, however, remain unclear. Here we use X-ray micro-computed tomography (μCT) to investigate RW-associated alterations in secondary xylem tissue patterning in three dimensions (3D).
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Reaction Wood – a key cause of variation in cell wall recalcitrance in willow
Biotechnology for biofuels, 2012Co-Authors: Nicholas J. B. Brereton, Michael J. Ray, Ian Shield, Peter Martin, Angela Karp, Richard J. MurphyAbstract:Background The recalcitrance of lignocellulosic cell wall biomass to deconstruction varies greatly in angiosperms, yet the source of this variation remains unclear. Here, in eight genotypes of short rotation coppice willow (Salix sp.) variability of the Reaction Wood (RW) response and the impact of this variation on cell wall recalcitrance to enzymatic saccharification was considered.
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Reaction Wood a key cause of variation in cell wall recalcitrance in willow
Biotechnology for Biofuels, 2012Co-Authors: Nicholas J. B. Brereton, Michael J. Ray, Ian Shield, Peter Martin, Angela Karp, Richard J. MurphyAbstract:Background The recalcitrance of lignocellulosic cell wall biomass to deconstruction varies greatly in angiosperms, yet the source of this variation remains unclear. Here, in eight genotypes of short rotation coppice willow (Salix sp.) variability of the Reaction Wood (RW) response and the impact of this variation on cell wall recalcitrance to enzymatic saccharification was considered.
Nicholas J. B. Brereton - One of the best experts on this subject based on the ideXlab platform.
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X-ray micro-computed tomography in willow reveals tissue patterning of Reaction Wood and delay in programmed cell death
BMC plant biology, 2015Co-Authors: Nicholas J. B. Brereton, Michael J. Ray, Ian Shield, Angela Karp, Farah Ahmed, Dan Sykes, Richard J. MurphyAbstract:Background Variation in the Reaction Wood (RW) response has been shown to be a principle component driving differences in lignocellulosic sugar yield from the bioenergy crop willow. The phenotypic cause(s) behind these differences in sugar yield, beyond their common elicitor, however, remain unclear. Here we use X-ray micro-computed tomography (μCT) to investigate RW-associated alterations in secondary xylem tissue patterning in three dimensions (3D).
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Reaction Wood – a key cause of variation in cell wall recalcitrance in willow
Biotechnology for biofuels, 2012Co-Authors: Nicholas J. B. Brereton, Michael J. Ray, Ian Shield, Peter Martin, Angela Karp, Richard J. MurphyAbstract:Background The recalcitrance of lignocellulosic cell wall biomass to deconstruction varies greatly in angiosperms, yet the source of this variation remains unclear. Here, in eight genotypes of short rotation coppice willow (Salix sp.) variability of the Reaction Wood (RW) response and the impact of this variation on cell wall recalcitrance to enzymatic saccharification was considered.
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Reaction Wood a key cause of variation in cell wall recalcitrance in willow
Biotechnology for Biofuels, 2012Co-Authors: Nicholas J. B. Brereton, Michael J. Ray, Ian Shield, Peter Martin, Angela Karp, Richard J. MurphyAbstract:Background The recalcitrance of lignocellulosic cell wall biomass to deconstruction varies greatly in angiosperms, yet the source of this variation remains unclear. Here, in eight genotypes of short rotation coppice willow (Salix sp.) variability of the Reaction Wood (RW) response and the impact of this variation on cell wall recalcitrance to enzymatic saccharification was considered.
Patricia Roeckel-drevet - One of the best experts on this subject based on the ideXlab platform.
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The molecular mechanisms of Reaction Wood induction
2014Co-Authors: Kurt Fagerstedt, Kévin Tocquard, David Lopez, Mélanie Decourteix, Bernard Thibaut, Jean-louis Julien, Philippe Label, Nathalie Fournier-leblanc, Patricia Roeckel-drevetAbstract:Reaction Wood originates from cambial activity which will adjust cell division activity, cell wall structure and properties, so that the resulting growth event will be the appropriate response to endogenous and environmental stimuli. When addressing the question of the induction of Reaction Wood formation, the physical parameters inducing Reaction Wood are first presented leading to discuss the importance of gravisensing versus proprioception (sensing of the local curvature of the stem) in this process. Molecular candidates for the perception of cellular deformation that is hypothesized to occur in a gravistimulated stem are located at CPMCW (cytoskeleton-plasma membrane-cell wall) continuum. These candidates would mediate intracellular signalling. Insights from global approaches (e.g. transcriptome and proteome analyses) performed on tilted trees suggest calcium, reactive oxygen species and phosphatidy linositol signalling in the gravitropism sensing network. It has been unambiguously shown that several of the aux/IAA gene family mediators of auxin signal transduction pathway change on induction of tension Wood formation. Gibberellins and ethylene seem also to be involved in Reaction Wood formation. The role of the different plant hormones in upstream primary response to Reaction Wood sensing or alternatively in the transmission of the signal from the perception to the Reaction Wood forming cells is discussed.
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The molecular mechanisms of Reaction Wood induction.
2014Co-Authors: Kévin Tocquard, David Lopez, Mélanie Decourteix, Bernard Thibaut, Jean-louis Julien, Philippe Label, Nathalie Fournier-leblanc, Patricia Roeckel-drevetAbstract:The book is an essential reference source on Reaction Wood for Wood scientists and technologists, plant biologists, silviculturists, forest ecologists, and anyone involved in the growing of trees and the processing of Wood. It brings together our current understanding of all aspects of Reaction Wood, and is the first book to compare and discuss both compression Wood and tension Wood. Trees produce Reaction Wood to maintain the vertical orientation of their stems and the optimum angle of each branch. They achieve this by laying down fibre cell walls in which differences in physical and chemical structure from those of normal fibres are expressed as differential stresses across the stem or branch. This process, while of obvious value for the survival of the tree, causes serious problems for the utilisation of timber. Timber derived from trees containing significant amounts of Reaction Wood is subject to dimensional instability on drying, causing distortion and splitting. It is also difficult to work as timber, and for the pulp and paper industry the cost of removing the increased amount of lignin in compression Wood is substantial. This has both practical and economic consequences for industry. Understanding the factors controlling Reaction Wood formation and its effect on Wood structure is therefore fundamental to our understanding of the adaptation of trees to their environment and to the sustainable use of Wood.
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The molecular mechanisms of Reaction Wood induction.
The Biology of Reaction Wood, 2013Co-Authors: Kévin Tocquard, David Lopez, Mélanie Decourteix, Bernard Thibaut, Jean-louis Julien, Philippe Label, Nathalie Leblanc-fournier, Patricia Roeckel-drevetAbstract:Reaction Wood originates from cambial activity which adjust cell division activity, proportion of fibres, cell wall structure and properties, so that the resulting growth event will be the appropriate response to endogenous and environmental stimuli.
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Could thioredoxin h be involved in early response to gravitropic stimulation of poplar stems
2013Co-Authors: Wassim Azri, Jean-louis Julien, Eric Badel, Nicole Brunel, Jérôme Franchel, I. Ben-rejeb, Jean-pierre Jacquot, Stéphane Herbette, Patricia Roeckel-drevetAbstract:The perception of gravity is essential for plant development. Trees constantly develop specialized Woody tissues, termed « Reaction Wood » to correct inclined branch and stem growth in order to adopt an optimal position. Despite the economical impact of Reaction Wood occurrence and its importance from a developmental point of view, the perception and response to the gravitational stimulus have not been extensively studied in Woody species in which primary and secondary growth occur. Using complementary approaches (proteomics, qRT-PCR, immunolocalization), we have compared straight polar stems to stems that were inclined at 35° from the vertical axis for periods of time varying from 10 min to 6 hours depending on the experiments. The proteomics approach revealed that thirty six percent of the identified proteins that were differentially expressed after gravistimulation were established as potential Thioredoxin targets. qRT-PCR indicated an early induction of Thioredoxin h expression following gravistimulation. In situ immunolocalization indicated that Thioredoxin h protein co-localized with the amyloplasts located in the endodermal cells which may be specialized in gravity perception. These investigations suggest the involvement of Thioredoxin h in the first events of signal transduction in inclined poplar stems, leading to Reaction Wood formation.
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Proteome analysis of apical and basal regions of poplar stems under gravitropic stimulation.
Physiologia plantarum, 2009Co-Authors: Wassim Azri, Jean-louis Julien, Nicole Brunel, Stéphane Herbette, Christophe Chambon, Catherine Coutand, Jean-charles Leplé, Ichrak Ben Rejeb, Saïda Ammar, Patricia Roeckel-drevetAbstract:Gravity is a constant force guiding the direction of plant growth. In young poplar stem, reorientation of the apical region is mainly obtained by differential growth of elongating primary tissues. At the base, where elongation is achieved but where the cambium is active, reorientation is due to asymmetrical formation of Reaction Wood. After 45 min of gravistimulation, the stem showed no reorientation, but 1 week later, Reaction Wood was observed at the base of the stem. To determine the molecular mechanisms taking place at the top and base of the stem, after 45 min or 1 week of inclination, the changes induced in protein accumulation were studied by two-dimensional polyacrylamide gel electrophoresis and quantitatively analyzed using image analysis software. Around 300 protein spots were reproducibly detected and analyzed. Forty percent of these proteins showed significant changes after inclination. Mass spectrometry analysis of 135 spots led to the identification of 60 proteins involved in a wide range of activities and metabolisms. Very different patterns of protein expression were obtained according to conditions tested, highlighting the complexity of gravitropic responses. Our results suggest that primary and secondary tissues present specific mechanisms to sense reorientation and to respond to inclination. Some selected proteins are discussed.
Nobuo Yoshizawa - One of the best experts on this subject based on the ideXlab platform.
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Anatomy and lignin distribution of “compression-Wood-like Reaction Wood” in gardenia jasminoides
IAWA Journal, 2013Co-Authors: Haruna Aiso, Futoshi Ishiguri, Shinso Yokota, Kazuya Iizuka, Tokiko Hiraiwa, Nobuo YoshizawaAbstract:Anatomical characteristics and lignin distribution of ‘compression-Wood-like Reaction Wood’ in Gardenia jasminoides Ellis were investigated. Two coppiced stems of a tree were artificially inclined to form Reaction Wood (RW). One stem of the same tree was fixed straight as a control, and referred to as normal Wood (NW). Excessive positive values of surface-released strain were measured on the underside of RW stems. Anatomical characteristics of xylem formed on the underside of RW and in NW stems were also observed. The xylem formed on the underside exhibited a lack of S3 layer in the secondary fibre walls, an increase of pit aperture angle in the S2 layer, and an increase in lignin content. Some of the anatomical characteristics observed in the underside xylem resembled compression Wood in gymnosperms. These results suggest that the increase of microfibril angle in the secondary wall and an increase in lignin content in angiosperms might be common phenomena resembling compression Wood of gymnosperms.
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Wood Anatomy of nine Japanese HardWood species forming Reaction Wood without gelatinous fibers
IAWA Journal, 2010Co-Authors: R.s. Sultana, Futoshi Ishiguri, Shinso Yokota, Kazuya Iizuka, Tokiko Hiraiwa, Nobuo YoshizawaAbstract:The anatomy of Reaction Wood was studied in nine naturally growing Japanese hardWood species, all showing eccentric growth on the upper side of their leaning branches. The number of vessels decreased in the xylem of the upper side accompanying the formation of Reaction Wood. A typical G-layer was not detected in the Reaction Wood fibers, but an S3 layer was present in all nine species. The cellulose microfibril arrangement with an S helix was similar in the S3 layers of both Reaction and opposite Wood fibers. A decrease of lignin content occurred in the Reaction Wood fibers in all nine species. The coniferyl and sinapyl aldehyde units in the lignins were strongly reduced in the S2 layer of Reaction Wood fibers of four species, i.e., Euscaphis japonica, Rhododendron wadanum, Clerodendron trichotomum, and Daphne odora, and much less so in five other species, i.e., Viburnum dilatatum, Enkianthus subsessilis, Euonymus alatus, Ilex macropoda, and Ilex crenata. The syringyl content was lower in the S2 layer of Reaction Wood fibers than that in opposite Wood of all nine species. On the other hand, chemical analysis of lignin using the acetyl bromide method showed that, among the nine species, lignin content was reduced most strongly in Clerodendron trichotomum. Tension Wood-like characteristics are present on the upper side of leaning branches in all nine species, except that G-fibers are absent.
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Formation and Structure of Reaction Wood Fibers Forming No G-Layer in Some HardWood Species
Improvement of Forest Resources for Recyclable Forest Products, 2004Co-Authors: Nobuo Yoshizawa, Futoshi Ishiguri, Shinso Yokota, Toshihiro OnaAbstract:Woody plants develop special tissues, which are called Reaction Wood, on the inclined stems or branches. Tension Wood, Reaction Wood for hardWoods, can be characterized by the presence of gelatinous (G) -fibers which contain a thickened cellulosic inner layer (G-layer) [1, 2, 3]. However, some species of primitive hardWoods have been reported to frequently lack of G-fibers [4, 5, 6, 7]. No detailed information is available about the structure and chemical composition of tention Wood fibers in these species. In this paper, anatomical features of the tention Wood fibers in three species forming no G-layer were observed. In addition, distribution of guaiacyl- and syringyl-type lignins in the cell walls of both normal and tention Wood fibers was examined by visible light (VL) combined with microspectrophotometry after the Wiesner and Maule Reactions.
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Anatomy and lignin distribution of Reaction Wood in two Magnolia species
Wood Science and Technology, 2000Co-Authors: Nobuo Yoshizawa, Futoshi Ishiguri, A. Inami, S. Miyake, Shinso YokotaAbstract:Anatomical features of Reaction Wood formed in two Magnolia species, M. obovata Thunb. and M. kobus DC. which are considered to be among the primitive angiosperms, were observed. In addition, the distribution of guaiacyl and syringyl units of lignins in the cell walls of normal and Reaction Wood was examined using ultraviolet (UV)- and visible light (VL)- microspectrophotometry coupled with the Wiesner and Maule Reactions. The two Magnolia species formed a tension-like Reaction Wood without possessing the typical gelatinous layer (G-layer) on the upper side of the inclined stem or branch, in which a radial growth promotion occurred. Compared with the normal Wood, the Reaction Wood had the following anatomical features: (1) the secondary walls of fiber tracheids lacked the S3 layer, (2) the innermost layer of fiber-tracheid walls showed a small microfibril angle, a fact being similar to the orientation of the microfibril angle of the G-layer in tension Wood, and (3) the amounts of lignin decreased in the cell walls of fiber tracheids, especially with great decrease in proportion of guaiacyl units in lignins. In addition, VL-microspectrophotometry coupled with the Wiesner and Maule Reactions adopted in the present study showed potential to estimate the lignin contents in the cell walls and the proportion of guaiacyl and syringyl units in lignins.
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Formation and structure of Reaction Wood in Buxus microphylla var. insularis Nakai
Wood Science and Technology, 1992Co-Authors: Nobuo Yoshizawa, Sbinso Yokota, M. Satoh, Toshihiro IdeiAbstract:Anatomical differences in xylem between the upper and lower sides formed in the inclined stems of Buxus microphylla with different angular displacement from the vertical were examined microscopically. B. microphylla exhibited a pronounced growth promotion on the lower side of the inclined stems. Formation of tension Wood (gelatinous fibers) was not observed. Xylem formed on the lower side showed some interesting features resembling the compression Wood formed in gymnosperms. The Reaction Wood tracheids and vessels showed an excessive lignification in their secondary walls but lacked both helical cavities and an S_3 layer, features that were almost the same as those of primitive gymnosperms. These results indicate that B. microphylla has an ability to form compression Wood, suggesting that in the genus Buxus a different mechanism in the conducting elements was developed in the phylogenetic evolution.
Angela Karp - One of the best experts on this subject based on the ideXlab platform.
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X-ray micro-computed tomography in willow reveals tissue patterning of Reaction Wood and delay in programmed cell death
BMC plant biology, 2015Co-Authors: Nicholas J. B. Brereton, Michael J. Ray, Ian Shield, Angela Karp, Farah Ahmed, Dan Sykes, Richard J. MurphyAbstract:Background Variation in the Reaction Wood (RW) response has been shown to be a principle component driving differences in lignocellulosic sugar yield from the bioenergy crop willow. The phenotypic cause(s) behind these differences in sugar yield, beyond their common elicitor, however, remain unclear. Here we use X-ray micro-computed tomography (μCT) to investigate RW-associated alterations in secondary xylem tissue patterning in three dimensions (3D).
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Reaction Wood – a key cause of variation in cell wall recalcitrance in willow
Biotechnology for biofuels, 2012Co-Authors: Nicholas J. B. Brereton, Michael J. Ray, Ian Shield, Peter Martin, Angela Karp, Richard J. MurphyAbstract:Background The recalcitrance of lignocellulosic cell wall biomass to deconstruction varies greatly in angiosperms, yet the source of this variation remains unclear. Here, in eight genotypes of short rotation coppice willow (Salix sp.) variability of the Reaction Wood (RW) response and the impact of this variation on cell wall recalcitrance to enzymatic saccharification was considered.
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Reaction Wood a key cause of variation in cell wall recalcitrance in willow
Biotechnology for Biofuels, 2012Co-Authors: Nicholas J. B. Brereton, Michael J. Ray, Ian Shield, Peter Martin, Angela Karp, Richard J. MurphyAbstract:Background The recalcitrance of lignocellulosic cell wall biomass to deconstruction varies greatly in angiosperms, yet the source of this variation remains unclear. Here, in eight genotypes of short rotation coppice willow (Salix sp.) variability of the Reaction Wood (RW) response and the impact of this variation on cell wall recalcitrance to enzymatic saccharification was considered.
