Tetcyclasis and abscisic acid-sensitive reduction of extracellular ferricyanide by mesophyll cells of Valerianella locusta and Lemna gibba

Electron transport across the plasma membrane of Valerianella locusta mesophyll cells and intact fronds of Lemna gibba, induced by 10 super(-3) M ferricyanide, was inhibited by tetcyclacis, an inhibitor regarded to be specific for cytochrome P-450 mono-oxygenases. The effect was dependent on the con...

Full description

Saved in:
Bibliographic Details
Published in:Journal of experimental botany 1993-01, Vol.44 (258), p.35-39
Main Authors: Betz, C, Ullrich, C I, Hartung, W
Format: Article
Language:English
Subjects:
Freshwater
Lemna gibba
Valerianella locusta
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Electron transport across the plasma membrane of Valerianella locusta mesophyll cells and intact fronds of Lemna gibba, induced by 10 super(-3) M ferricyanide, was inhibited by tetcyclacis, an inhibitor regarded to be specific for cytochrome P-450 mono-oxygenases. The effect was dependent on the concentration of tetcyclacis and the duration of preincubation. The apparent rate of transmembrane electron transport increased in the presence of catalase, indicating tetcyclacis-induced H sub(2)O sub(2)-production or additional tetcyclacis-independent H sub(2)O sub(2) release. The findings suggest an interaction of cytochrome P-450 with the plasma membrane-located electron transport chain. This redox-chain could be involved in the degradation of abscisic acid, being located at the plasma membrane. This assumption is supported by the finding that ABA inhibits extracellular ferricyanide reduction.
ISSN:0022-0957