Title
An anion conductance, the essential component of the hydroxyl-radical-induced Ion current in plant roots
Author
IGOR POTTOSIN
ALBERTO ISAAC ZEPEDA JAZO
JAYACUMAR BOSE
Access level
Open Access
Alternative identifier
isni/0000 0004 0428 7635
isni/0000 0004 0611 9213
Subjects
Summary or description
Oxidative stress signaling is essential for plant adaptation to hostile environments. Previous studies revealed the essentiality of hydroxyl radicals (HO•)-induced activation of massive K+ efflux and a smaller Ca2+ influx as an important component of plant adaptation to a broad range of abiotic stresses. Such activation would modify membrane potential making it more negative. Contrary to these expectations, here, we provide experimental evidence that HO• induces a strong depolarization, from −130 to −70 mV, which could only be explained by a substantial HO•-induced efflux of intracellular anions. Application of Gd3+ and NPPB, non-specific blockers of cation and anion conductance, respectively, reduced HO• induced ion fluxes instantaneously, implying a direct block of the dual conductance. The selectivity of an early instantaneous HO•-induced whole cell current fluctuated from more anionic to more cationic and vice versa, developing a higher cation selectivity at later times. The parallel electroneutral efflux of K+ and anions should underlie a substantial leak of the cellular electrolyte, which may affect the cell’s turgor and metabolic status. The physiological implications of these findings are discussed in the context of cell fate determination, and ROS and cytosolic K+ signaling
Publisher
MDPI
Publish date
March 18, 2018
Publication type
Article
Information Resource
Language
English
Source repository
Repositorio institucional de la Universidad de Colima
Downloads
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