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Stahlberg R, Stephens NR, Cleland RE, et al. Shade-Induced Action Potentials in Helianthus annuus L. Originate Primarily from the Epicotyl. Plant Signal Behav. 2006;1(1):15-22doi: 10.4161/psb.1.1.2275.
Stahlberg, R., Stephens, N. R., Cleland, R. E., & Van Volkenburgh, E. (2006). Shade-Induced Action Potentials in Helianthus annuus L. Originate Primarily from the Epicotyl. Plant signaling & behavior, 1(1), 15-22. https://doi.org/10.4161/psb.1.1.2275
Stahlberg, Rainer, et al. "Shade-Induced Action Potentials in Helianthus annuus L. Originate Primarily from the Epicotyl." Plant signaling & behavior vol. 1,1 (2006): 15-22. doi: https://doi.org/10.4161/psb.1.1.2275
Stahlberg R, Stephens NR, Cleland RE, Van Volkenburgh E. Shade-Induced Action Potentials in Helianthus annuus L. Originate Primarily from the Epicotyl. Plant Signal Behav. 2006 Jan;1(1):15-22. doi: 10.4161/psb.1.1.2275. PMID: 19521471; PMCID: PMC2633695.
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Plant Signal Behav. 2006 Jan;1(1):15-22. doi: 10.4161/psb.1.1.2275.

Shade-Induced Action Potentials in Helianthus annuus L. Originate Primarily from the Epicotyl.

Plant signaling & behavior

Rainer Stahlberg, Nicholas R Stephens, Robert E Cleland, Elizabeth Van Volkenburgh

Affiliations

  1. Department of Biology; University of Washington; Seattle, Washington USA.

PMID: 19521471 PMCID: PMC2633695 DOI: 10.4161/psb.1.1.2275

Abstract

Repeated observations that shading (a drastic reduction in illumination rate) increased the generation of spikes (rapidly reversed depolarizations) in leaves and stems of many cucumber and sunflower plants suggests a phenomenon widespread among plant organs and species. Although shaded leaves occasionally generate spikes and have been suggested to trigger systemic action potentials (APs) in sunflower stems, we never found leaf-generated spikes to propagate out of the leaf and into the stem. On the contrary, our data consistently implicate the epicotyl as the location where most spikes and APs (propagating spikes) originate. Microelectrode studies of light and shading responses in mesophyll cells of leaf strips and in epidermis/cortex cells of epicotyl segments confirm this conclusion and show that spike induction is not confined to intact plants. 90% of the epicotyl-generated APs undergo basipetal propagation to the lower epicotyl, hypocotyl and root. They propagate with an average rate of 2 +/- 0.3 mm s(-1) and always undergo a large decrement from the hypocotyl to the root. The few epicotyl-derived APs that can be tracked to leaf blades (< 10%) undergo either a large decrement or fail to be transmitted at all. Occasionally (5% of the observations) spikes were be generated in hypocotyl and lower epicotyl that moved towards the upper epicotyl unaltered, decremented, or amplified. This study confirms that plant APs arise to natural, nontraumatic changes. In simultaneous recordings with epicotyl growth, AP generation was found to parallel the acceleration of stem growth under shade. The possible relatedness of both processes must be further investigated.

Keywords: AP propaqgation; Helianthus annuus L.; action potentials; amplification; decrement; natural induction; stem growth

References

  1. Plant Physiol. 1997 Nov;115(3):1083-1088 - PubMed
  2. Planta. 1996 Dec;200(4):416-25 - PubMed
  3. Plant Physiol. 1997 Jan;113(1):209-217 - PubMed
  4. Plant Cell Environ. 1984;7:171-8 - PubMed
  5. FEBS Lett. 1996 Jul 29;390(3):275-9 - PubMed
  6. Plant Cell Environ. 1995;18:33-41 - PubMed
  7. Planta. 1988 Apr;174(1):8-18 - PubMed
  8. Planta. 1978 Jan;138(2):173-9 - PubMed
  9. Plant Cell Environ. 1994;17:1143-51 - PubMed
  10. Planta. 1992 Jul;187(4):523-31 - PubMed
  11. Planta. 2000 Dec;212(1):1-8 - PubMed
  12. Planta. 2005 Feb;220(4):550-8 - PubMed
  13. Plant Physiol. 1992 May;99(1):96-102 - PubMed
  14. Symp Soc Exp Biol. 1966;20:49-73 - PubMed

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