Rapid systemic up-regulation of genes after heat-wounding and electrical stimulation

• Autorzy: Davies E , Vian A. , Vian C. , Stankovic B.
• Języki publikacji: EN

Abstrakty

EN

When one leaf of a tomato plant is electrically-stimulated or heat-wounded, proteinase inhibitor genes are rapidly up-regulated in distant leaves. The identity of the systemic wound signal(s) is not yet known, but major candidates include hormones transmitted via the phloem or the xylem, the electrically-stimulated self-propagating electrical signal in the phloem (the action potential, AP), or the heat-wound-induced surge in hydraulic pressure in the xylem evoking a local change in membrane potential in adjacent living cells (the variation potential, VP). In order to discriminate between these signals we have adopted two approaches. The first approach involves applying stimuli that evoke known signals and determining whether these signals have similar effects on the “model” transcripts for proteinase inhibitors (pin) and calmodulin (cal). Here we show that a heat wound almost invariably evokes a VP, while an electrical stimulation occasionally evokes an AP, and both of these signals induce accumulation of transcripts encoding proteinase inhibitors. The second approach involves identifying the array of genes turned on by heat-wounding. To this end, we have constructed a subtractive library for heat-wounded tissue, isolated over 800 putatively up-regulated clones, and shown that all but two of the fifty that we have analyzed by Northern hybridization are, indeed, up-regulated. Here we show the early kinetics of up-regulation of three of these transcripts in the terminal (4th) leaf in response to heat-wounding the 3rd leaf, about 5 cm away. Even though these transcripts show somewhat different time courses of induction, with one peaking at 30 min, another at 15 min, and another at 5 min after flaming of a distant leaf, they all exhibit a similar pattern, i.e., a transient period of transcript accumulation preceding a period of transcript decrease, followed by a second period of transcript accumulation.

Słowa kluczowe

EN

variation potential; gene; calmodulin; action potential; leaf; electrical stimulation; tomato

• Wydawca: -
• Czasopismo: Acta Physiologiae Plantarum
• Rocznik: 1997
• Tom: 19
• Numer: 4
• Opis fizyczny: p.571-576,fig.

Twórcy

autor

Davies E

autor

Vian A.

autor

Vian C.

autor

Stankovic B.

Bibliografia

• Bowles D.J. 1993. Local and systemic signals in the wound response. Sem.Cell Biol., 4: 103–111.
• Braam J., Davis R.W. 1990. Rain-, wind-, and touch-induced expression of calmodulin and calmodulin-related genes in Arabidopsis. Cell, 60: 357–364.
• Graham J.S., Hall G., Pearce G., Ryan C.A. 1986. Regulation of synthesis of proteinase inhibitors I and II mRNAs in leaves of wounded tomato plants. Planta, 169: 399–405.
• Herde O., Atzorn R., Fisahn J., Wasternack C., Wilmitzer L., Peńa-Cortes H. 1996. Localized wounding by heat initiates the accumulation of proteinase inhibitor II in abscisic acid-deficient plants by triggering jasmonic acid biosynthesis. Plant Physiol., 112: 853–860.
• Malone M., Alarcon J.-J., Palumbo L. 1994. A hydraulic interpretation of rapid, long-distance wound signaling in the tomato. Planta, 193: 181–185.
• McGurl B., Orozco-Cardenas M., Pearce G., Ryan C.A. 1994. Overexpression of the prosystemin gene in transgenic tomato plants generates a systemic signal that constitutively induces proteinase inhibitor synthesis. Proc. Natl. Acad. Sci. USA, 91: 9799–9802.
• Narvaez-Vasquez J., Pearce G., Orozco-Cardenas M.L., Franceschi V.R., Ryan C.A. 1995. Autoradiographic and biochemical evidence for the systemic translocation of systemin in tomato plants. Planta, 195: 593–600.
• Peńa-Cortes H., Fisahn J., Wilmitzer L. 1995. Signals involved in wound-induced proteinase inhibitor II gene expression in tomato and potato plants. Proc. Natl. Acad. Sci. USA, 92: 4106–4113.
• Stankovic B., Davies E. 1996. Both action potentials and variation potentials induce proteinase inhibitor gene expression in tomato. FEBS Lett., 390: 275–279.
• Stankovic B., Davies E. 1997. Intercellular communication in plants: electrical stimulation of proteinase inhibitor gene expression in tomato. Planta, 202: 402–406.
• Wildon D.C., Thain J.F., Minchin P.E.H., Gubb I.R., Reilly A.J., Skipper Y.D., Doherty H.M., O’Donnell P.J. Bowles D.J. 1992. Electrical signalling and systemic proteinase inhibitor induction in the wounded plant. Nature, 360: 62–65.