Real-time, in vivo intracellular recordings of caterpillar-induced depolarization waves in sieve elements using aphid electrodes.
Plants propagate electrical signals in response to artificial wounding. However, little is known about the electrophysiological responses of the phloem to wounding, and whether natural damaging stimuli induce propagating electrical signals in this tissue. Here, we used living aphids and the direct current (DC) version of the electrical penetration graph (EPG) to detect changes in the membrane potential of Arabidopsis sieve elements (SEs) during caterpillar wounding. Feeding wounds in the lamina induced fast depolarization waves in the affected leaf, rising to maximum amplitude (c. 60 mV) within 2 s. Major damage to the midvein induced fast and slow depolarization waves in unwounded neighbor leaves, but only slow depolarization waves in non-neighbor leaves. The slow depolarization waves rose to maximum amplitude (c. 30 mV) within 14 s. Expression of a jasmonate-responsive gene was detected in leaves in which SEs displayed fast depolarization waves. No electrical signals were detected in SEs of unwounded neighbor leaves of plants with suppressed expression of GLR3.3 and GLR3.6. EPG applied as a novel approach to plant electrophysiology allows cell-specific, robust, real-time monitoring of early electrophysiological responses in plant cells to damage, and is potentially applicable to a broad range of plant-herbivore interactions.
Department of Molecular Plant Biology, University of Lausanne, 1015, Lausanne, Switzerland.|Institute for Molecular Plant Physiology and Biophysics, Julius-von-Sachs-Platz 2, 97082, Würzburg, Germany.
Vicenta
V
Salvador-Recatalà
EPG Systems, Dillenburg 12, 6703, CJ Wageningen, the Netherlands.
W Freddy
WF
Tjallingii
Department of Molecular Plant Biology, University of Lausanne, 1015, Lausanne, Switzerland.
Edward E
EE
Farmer
D000818:Animals; D001042:Aphids; D017360:Arabidopsis / Q000235:genetics / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics; D003517:Cyclopentanes; D004594:Electrophysiology / Q000379:methods*; D005247:Feeding Behavior; D018506:Gene Expression Regulation, Plant; D060434:Herbivory; D008564:Membrane Potentials; D009687:Nuclear Proteins / Q000235:genetics; D054883:Oxylipins; D018515:Plant Leaves / Q000502:physiology*
D029681:Arabidopsis Proteins; D003517:Cyclopentanes; C525049:JAS1 protein, Arabidopsis; D009687:Nuclear Proteins; D054883:Oxylipins; C011006:jasmonic acid
Arabidopsis; aphid; electrical penetration graph (EPG); electrical signal; glutamate receptor-like channels; insect damage; ion channels; jasmonate; phloem