The transient nature of the oligogalaturonide‐induced ion fluxes of tobacco cells is not correlated with fragmentation of the oligogalacturonides

Abstract

SummaryThe metabolism by suspension-cultured tobacco cells of oligogalacturonides was investigated. Dodecagalacturonic acid-

Sensitivity of Different Ecotypes and Mutants ofArabidopsis thaliana toward the Bacterial Elicitor Flagellin Correlates with the Presence of Receptor-binding Sites

“…Suspension-cultured plant cells react to elicitors within minutes and have thus been widely used to study elicitor perception and elicitor responses (1). Changes in protein phosphorylation, activation of MAP kinases, and altered ion fluxes across the plasma membrane, including increased efflux of K ϩ and Cl Ϫ and increased influx of H ϩ and Ca 2ϩ are among the earliest responses observed (13)(14)(15)(16). These alterations in ion fluxes precede the actual defense responses and are believed to be involved in elicitor signaling.…”

Extracellular H2O2 Induced by Oligogalacturonides Is Not Involved in the Inhibition of the Auxin-Regulated rolB Gene Expression in Tobacco Leaf Explants

“…Because OGs have been shown to induce H 2 O 2 in several plant tissues and cells (Legendre et al, 1993;Svalheim and Robertsen, 1993;Levine et al, 1994;Mathieu et al, 1998;Spiro et al, 1998;Stennis et al, 1998;Orozco-Cardenas and Ryan, 1999), we determined whether this response also occurred in rolB-GUS explants. RolB-GUS explants were cultured in the presence of IAA (0.6 m), OGs (DP of 9-18; 10 g/mL), or water (controls) added at time 0 or 8 h later.…”

“…The earliest detectable responses induced by OGs are the activation of specific ion channels leading to influx of H ϩ and Ca 2ϩ and efflux of K ϩ (Messiaen and Van Cutsem, 1994;Mathieu et al, 1998;Spiro et al, 1998), and the transient formation of reactive oxygen species (ROS) such as O 2 Ϫ , H 2 O 2 , and ⅐OH (Svalheim and Robertsen, 1993;Levine et al, 1994). How OGs cause the generation of ROS is not known.…”

Desensitization of GSTF8 Induction by a Prior Chemical Treatment Is Long Lasting and Operates in a Tissue-Dependent Manner

“…For example, in some light responses, desensitization ranges from seconds to minutes (e.g. Govorunova et al, 1997;Mathieu et al, 1998;Baum et al, 1999), whereas desensitization of the mitogen-activated protein kinase response in tomato (Lycopersicon esculentum) to elicitors lasted less than 120 min (Holley et al, 2003). In soybean (Glycine max), cultured cells pretreated with a chemical elicitor were able to be quickly restimulated by the same or different elicitors, with the refractory period having a half-life of 20 min (Chandra et al, 2000).…”