Wound signal

Direction and Rate of Flow of the Wound Signal, PIIF... 

Naoumkina M, Farag MA, Summer LW, Tang Y, Liu C-J, Dixon RA. 2007. Different mechanism for phytoalexins induction by pathogen and wound signals in Medicago truncatula. Proc Natl Acad Sci USA 104 17909-17915. 

LE-ACS2 and LE-AC5 4 are expressed in fruits but not in etiolated seedlings (Mori unpublished results). LE-AC5 2 is not expressed in young and mature leaves, roots, petals and pistils, but is expressed in stamens, mature and senescent anthers, and senescent petals [93]. It appears that LE-AC5 2 is expressed in senescent tissues. Senescence is also accompanied by cell degradation which certainly generates the wound signal. 

LI, C.Y., LIU, G.H., XU, C.C., LEE, G.I., BAUER, P., LING, H.Q., GANAL, M.W., HOWE, G.A., The tomato Suppressor of prosystemin-mediated responses2 gene encodes a fatty acid desaturase required for the biosynthesis of jasmonic acid and the production of a systemic wound signal for defense gene expression. Plant Ce//, 2003,15, 1646-1661. 

Surprisingly, this treatment (excision of the apex) led to polysome formation which was greater 1 h after excision than 10 h after auxin treatment of the intact plant [8]. In efforts to circumvent this wound-evoked polysome formation, we excised the tissue at a point 5 cm below the apex and were again surprised. Polysome formation in the apical 1 cm was almost as massive as in tissue wounded at the 1 cm point. In fact, polysome formation took place in the apical 1 cm within 15 min of inflicting a wound at a point 20 cm distant. This led to our realization that there was a rapidly-generated (and bidirectionally-transmitted) wound signal that could very rapidly elicit polysome formation in distant tissue [8, 18]. 

Numerous physical, chemical and electrochemical wound signals have been described [4], with the two major candidates here being electrochemical (presumably action potentials) and hormonal (presumably ethylene). 

Campos-Vargas R, Saltveit ME (2002) Involvement of putative chemical wound signals in the induction of phenolic metabolism in wounded lettuce. Physiol Plant 114 73... 

Even a plant may communicate with long-distance calcium waves. S. A. Mousavi et al. Glutamate receptor-like genes mediate leaf-to-leaf wound signalling. 2013. Nature 500(7463), p. 422. DOI 10.1038/naturel2478. 

Park, J.H. et al. (2002) A knock-out mutation in allene oxide synthase results in male sterility and defective wound signal transduction in Arabidopsis due to a block in jasmonic acid biosynthesis. Plant J. 31, 1-12... 

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