In touch: plant responses to mechanical stimuli

Abstract

Contents Summary 1 Introduction 2 Fast and fascinating – thigmonasty and thigmotropism 2 Subcellular touch‐induced movements 10 Thigmomorphogenesis 10 Discovery of the Arabidopsis TCH genes 12 Microarray identification of touch‐inducible genes 12 Regulation of TCH gene expression 13 Acknowledgements 14 References 14 Summary Perception and response to mechanical stimuli are likely essential at the cellular and organismal levels. Elaborate and impressive touch responses of plants capture the imagination as such behaviors are unexpected in otherwise often quiescent creatures. Touch responses can turn plants into aggressors against animals, trapping and devouring them, and enable flowers to be active in ensuring crosspollination and shoots to climb to sunlit heights. Morphogenesis is also influenced by mechanical perturbations, including both dynamic environmental stimuli, such as wind, and constant forces, such as gravity. Even individual cells must sense turgor and wall integrity, and subcellular organelles can translocate in response to mechanical perturbations. Signaling molecules and hormones, including intracellular calcium, reactive oxygen species, octadecanoids and ethylene, have been implicated in touch responses. Remarkably, touch‐induced gene expression is widespread; more than 2.5% of Arabidopsis genes are rapidly up‐regulated in touch‐stimulated plants. Many of these genes encode calcium‐binding, cell wall modifying, defense, transcription factor and kinase proteins. With these genes as tools, molecular genetic methods may enable elucidation of mechanisms of touch perception, signal transduction and response regulation.

The mutual responses of higher plants to environment: Physiological and microbiological aspects

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“…This is the reason that ion homeostasis and redox state have been brought to attention [4][5][6][7][21][22][23][24][25][26][27][28][29][111][112][113][114][115][116][117][118][119]. The series of the above reactions and processes occurring at different soil-root biointerfaces is regulated and controlled by plant gene regulatory network system spatially and temporally on the basis of responding to plant developmental cues, through which plants can elegantly respond to the changing environment [8][9][10][11][12][13][14][15][16][17][18][45][46][47][48][49]62,[76][77][78][79][94][95][96][97][98]. This network system has be...…”

“…Physiological and microbiological responses of higher plants to environment have been studied extensively over the world, especially by targeting model plants and crop plants [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. Abiotic stresses in environment are linked with all the living process of higher plants and greatly influence plant productivity developmental cues and environmental stimuli, most of which are the important factors affecting eco-environment such as low temperature, drought, salinity and UV-B radiation, which often occur in terrestrial ecosystem.…”

Self-shaping composites with programmable bioinspired microstructures

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Actuation systems in plants as prototypes for bioinspired devices

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