title: Rapid Hormone-induced Hyperpolarization of the Oat Coleoptile Transmembrane Potential.
abstract: The effects of the plant growth substances indoleacetic acid (IAA) and fusicoccin on the transmembrane potential of Avena coleoptile cells (at 27-29 C) were studied. Fusicoccin caused hyperpolarization of the membrane potential which started after a lag of less than 20 seconds, and which on average reached -49 mv at an external K(+) concentration of 1 mm and -75 mv at 0.1 mm K(+). IAA caused a hyperpolarization of -25 mv starting after a lag of 7 to 8 minutes. These results suggest that fusicoccin and IAA both activate electrogenic H(+) extrusion.
authors: Department of Botany, Washington State University, Pullman, Washington 99163.
authors: R E
authors: RE
authors: Cleland
authors: H B
authors: HB
authors: Prins
authors: J R
authors: JR
authors: Harper
authors: N
authors: N
authors: Higinbotham