Role of xyloglucan in gravitropic bending of azuki bean epicotyl

Ikushima, Toshimitsu; Soga, Kouichi; Hoson, Takayuki; Shimmen, Teruo

doi:10.1111/j.1399-3054.2007.01047.x

Cited by 10 publications

(13 citation statements)

References 127 publications

(157 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As highlighted by the Darwins (1880), differential pressure in the upper and lower part is also a candidate explanation for differential growth during tropisms. However, direct measurements using cellular pressure probes demonstrate that, although changes in pressure do induce changes in strain rate in plants, no significant difference in pressure has been observed between the upper and lower parts of graviresponding organs (Tomos et al, 1989;Cosgrove, 1990b, Kutschera andNiklas, 2007;Ikushima et al, 2008).…”

Section: Osmo-hydraulic Motorsmentioning

confidence: 99%

“…A resistance is a biophysical process that counteracts the motor system by absorbing part of the free energy, either by storing it in a potential form that cannot be used for producing the movement (e.g. blocking of the gravitropic movement by a stiff stake storing elastic energy out of the gravitropic organ; Yamashita et al, 2007;Ikushima et al, 2008) or by dissipating this free energy into heat (a degraded form of energy) through some friction. There are two types of resistances: those internal to the motor (reducing its energetic efficiency) and those external.…”

Section: A Brief Overview Of the Molecular And Cellular Biology Of Grmentioning

confidence: 99%

“…The visco-plastic resistance of the cell wall decreases quickly with auxin, at least in the epidermal outer cell wall (see Kutschera and Niklas, 2007 for a review). This is probably due to cell wall acidification triggering expansin-dependent weakening of hydrogen bonds and, in the longer term, to auxin-induced expression of expansin (Muday and Rahman, 2008, but see counterarguments in Ikushima et al, 2008). Differential changes in pectin and xyloglucan polymer size in the upper and lower parts of bean epicotyls also correlates to differential changes in wall extensibility as a response to inclination, and not bending (Ikushima et al,.…”

Section: Osmo-hydraulic Motorsmentioning

confidence: 99%

“…(TW, tension wood; NW, normal wood.) exocytotic rate of matrix polymer deposition (see Ikushima et al, 2008, for a review). Note that it is bending, but not inclination angle, that has been shown to induce differential changes in the cortical microtubules (MT) between the upper and lower epidermis during gravitropic movement.…”

Section: Osmo-hydraulic Motorsmentioning

confidence: 99%

“…Consider the case of mutants or inhibitors affecting cytoskeleton dynamics (Palmieri et al, 2007). Cytoskeleton dynamics is known potentially to affect statolith movements (Morita and Tasaka, 2004), mechanosensing (Perbal and Driss-Ecole, 2003), PIN relocalization, cell wall growth (Ikushima et al, 2008), and the list could well go on! Using integrative models and related experiments, it might be possible quantitatively to analyse the individual contributions of these effects to the overall gravitropic phenotype (Meskauskas et al, 1999b;Moulia et al, 2006).…”

Section: De Mðs;tþdtþ %mentioning

confidence: 99%

See 4 more Smart Citations

The power and control of gravitropic movements in plants: a biomechanical and systems biology view

Moulia

Fournier

2009

Journal of Experimental Botany

155

198

View full text Add to dashboard Cite

The study of gravitropic movements in plants has enjoyed a long history of research going back to the pioneering works of the 19th century and the famous book entitled 'The power of movement in plants' by Charles and Francis Darwin. Over the last few decades, the emphasis has shifted towards the cellular and molecular biology of gravisensing and the onset of auxin gradients across the organs. However, our understanding of plant movement cannot be completed before quantifying spatio-temporal changes in curvature and how they are produced through the motor process of active bending and controlled by gravisensing. This review sets out to show how combining approaches borrowed from continuum mechanics (kinematic imaging, structural modelling) with approaches from physiology and modern molecular biology has made it possible to generate integrative biomechanical models of the processes involved in gravitropism at several levels. The physiological and biomechanical bases are reviewed and two of the most complete integrative models of the gravireaction organ available are then compared, highlighting how the comparison between movements driven by differential growth and movements driven by reaction wood formation in woody organs has provided highly informative key insights. The advantages of these models as tools for analysing genetic control through quantitative process-based phenotyping as well as for identifying target traits for ecological studies are discussed. It is argued that such models are tools for a systems biology approach to gravitropic movement that has the potential to resolve at least some of the research questions raised 150 years ago.

show abstract

Section: Osmo-hydraulic Motorsmentioning

confidence: 99%

Section: A Brief Overview Of the Molecular And Cellular Biology Of Grmentioning

confidence: 99%

Section: Osmo-hydraulic Motorsmentioning

confidence: 99%

Section: Osmo-hydraulic Motorsmentioning

confidence: 99%

Section: De Mðs;tþdtþ %mentioning

confidence: 99%

See 3 more Smart Citations

The power and control of gravitropic movements in plants: a biomechanical and systems biology view

Moulia

Fournier

2009

Journal of Experimental Botany

155

198

View full text Add to dashboard Cite

show abstract

Physical and Mechanical Properties of Reaction Wood

Clair

Thibaut

2013

The Biology of Reaction Wood

View full text Add to dashboard Cite

Reaction wood produces very peculiar maturation stresses at the tree periphery, i.e. compressive stress or very high tensile stress, for compression and tension wood, respectively, as compared to moderately high tensile stress for normal wood. This means that both its mechanical state and its mechanical and physical properties differ from normal wood.Compression wood shows big differences from normal wood in conifers, for all physical and mechanical properties: higher density and axial crushing strength (MOR) but lower modulus of elasticity (MOE), far higher axial (longitudinal) shrinkage but lower radial and tangential shrinkage, sometimes even lower than the axial shrinkage.For tension wood things are less simple and can vary a lot from hardwood species to species. Globally there are no systematic differences in density and transverse shrinkage; MOE tends to be a little higher while MOR is slightly lower. However, axial shrinkage is much higher for tension wood with a gelatinous layer (G layer) than normal wood due to the specific gel-like organization of matrix in the G layer. For tension wood without a G layer (which is rather frequent) axial shrinkage is around two times higher than in normal wood. This paradoxical shrinkage is thought to originate from the release of maturation stresses during drying.Overall the very high tensile stress and stored elastic energy in tension wood lead to problems in wood processing (end splitting and board warping), which is far less the case for compression wood. But due to the large difference in properties relative B. Clair (*)

show abstract