TY - JOUR ID - 2420 TI - Receptor-mediated activation of a plant Ca2+-permeable ion channel involved in pathogen defense JO - Proc. Natl. Acad. Sci. U.S.A. PY - 1997 SP - 2751-2755 AU - Zimmermann, S. AU - Nürnberger, T. AU - Frachisse, J.-M. AU - Wirtz, W. AU - Guern, J. AU - Hedrich, R. AU - Scheel, D. AU - VL - 94 UR - DO - 10.1073/pnas.94.6.2751 AB - Pathogen recognition at the plant cell surface typically results in the initiation of a multicomponent defense response. Transient influx of Ca2+ across the plasma membrane is postulated to be part of the signaling chain leading to pathogen resistance. Patch-clamp analysis of parsley protoplasts revealed a novel Ca2+-permeable, La3+-sensitive plasma membrane ion channel of large conductance (309 pS in 240 mM CaCl2). At an extracellular Ca2+ concentration of 1 mM, which is representative of the plant cell apoplast, unitary channel conductance was determined to be 80 pS. This ion channel (LEAC, for large conductance elicitor-activated ion channel) is reversibly activated upon treatment of parsley protoplasts with an oligopeptide elicitor derived from a cell wall protein of Phytophthora sojae. Structural features of the elicitor found previously to be essential for receptor binding, induction of defense-related gene expression, and phytoalexin formation are identical to those required for activation of LEAC. Thus, receptor-mediated stimulation of this channel appears to be causally involved in the signaling cascade triggering pathogen defense in parsley. A2 - C1 - Biochemistry of Plant Interactions ER -