title: Elicitor-Induced Changes in Ca2+ Influx, K+ Efflux, and 4-Hydroxybenzoic Acid Synthesis in Protoplasts of Daucus carota L.
abstract: Suspension-cultured carrot cells (Daucus carota) and their protoplasts respond to a fungal elicitor prepared from the culture medium of Pythium aphanidermatum by accumulating 4-hydroxybenzoic acid (4-HBA). Protoplasts release the compound into the culture medium. Using 45CaCl2 as a tracer, we were able to demonstrate that the secretion of 4-HBA is preceded by a rapid increase in the Ca2+ influx and a concomitant K+ efflux. If the increased Ca2+ influx was prevented by ethyleneglycol-bis([beta]-aminoethylether)-N,N[prime]-tetraacetic acid, 4-HBA synthesis was inhibited by 70%. These results are discussed with regard to signal transduction from the plasma membrane to the nucleus of carrot protoplasts.
authors.affiliation: Botanical Institute, University of Tubingen, Auf der Morgenstelle 1, D-72076 Tubingen, Germany.
authors.forename: M.
authors.initials: M
authors.lastname: Bach
authors.forename: J. P.
authors.initials: JP
authors.lastname: Schnitzler
authors.forename: H. U.
authors.initials: HU
authors.lastname: Seitz