Morphological Responses and Molecular Modifications in Tomato Plants after Mechanical Stimulation

Abstract

Study of the growth responses of Lycopersicon esculentum (Mill. cv. VFN8) to mechanical stimulation applied to a single young internode showed a rapid and sharp decrease in stem elongation and an inhibition of elongation of several internodes, indicative of information transmission in the plant. A new tomato cDNA partial clone encoding calmodulin was isolated and used to study the time course of the gene induction in response to the rubbing treatment. Northern blot analysis showed a maximum accumulation of calmodulin mRNA 2 h after mechanical stimulation, not only in the rubbed internode, but also in upper and lower internodes and in young leaves. Treatment of the plant with calcium and EGTA showed the involvement of calcium and, in particular, intracellular calcium in calmodulin gene expression and cellular response.

High frequency (900 MHz) low amplitude (5 V m−1) electromagnetic field: a genuine environmental stimulus that affects transcription, translation, calcium and energy charge in tomato

“…Since all of the transcripts: calm-n6 (Depège et al 1997), lecdpk1 (Chico et al 2002) and pin2 (Pearce et al 1991) are wound-up-regulated, we were able to further probe the similarities between wounding and RF-EMF treatment and since two of them (calm-n6, lecdpk1) encode calcium-binding proteins, we examined the eVects of varying calcium availability to determine if there was any feedback mechanism involved in their transcription. Finally, we also measured ATP concentration and adenylate energy charge (AEC) after RF-EMF exposure, as well as the eVect of a potent uncoupling agent, CCCP, on transcript accumulation, in order to assess the inXuence of RF-EMF on plant cell energy status and to correlate this with changes in mRNA abundances.…”

Microwave Irradiation Affects Gene Expression in Plants

“…Plants may be appropriate experimental subjects, in the sense that they are highly sensitive to environmental signals [9][10][11] and plant studies raise less emotional concern than studies on animals or humans. Moreover, radiation from a GSM telephone or from a 105 GHz Gunn oscillator has been shown to have an effect comparable to that of a variety of environmental stimuli (such as manipulation stress, drought, wind and cold shock) in inducing physiological modifications (production of numerous epidermal meristems in the hypocotyls) or modifications of the proteome (pI shift, appearance or disappearance of a spot in 2D electrophoresis) in flax seedlings; [12][13][14][15] modifications of the proteome have also been observed in Arabidopsis seedlings subjected to stimuli such as cold shock or radiation from a GSM telephone.…”

Ara-Rhizotron: An Effective Culture System to Study Simultaneously Root and Shoot Development of Arabidopsis

“…Compared to substrate cultures, hydroponic culture has the advantage of being easier to sample root systems. But, even if root observations are not destructive, manipulations of plants can cause stress, which modifies plant growth and functioning (Bloom and Sukrapanna, 1990;Depege et al, 1997;Giridhar and Jaffe, 1988;Latimer, 1998;McKendree and Smith, 1990). In addition, the period of morphological study is limited because roots get into a tangle after about 15 days of culture.…”