title: Helminthosporium maydis T Toxin Increased Membrane Permeability to Ca in Susceptible Corn Mitochondria.
abstract: Though Helminthosporium maydis race T (HmT) toxin decreased active Ca(2+) uptake into mitochondria isolated from susceptible (T) but not resistant (N) corn (Kimber, Sze, 1984 Plant Physiol 74: 804-809 the mode of toxin action is not understood. This study shows that HmT toxin or A23187 (a Ca(2+) ionophore) dissipated a Ca(2+) gradient in T mitochondria. However, HmT toxin had no effect on Ca(2+) gradients in N mitochondria or microsomal vesicles from T or N corn. The results suggest that HmT toxin increased membrane permeability to Ca(2+) in mitochondria of T corn specifically.
authors: Department of Botany, University of Maryland, College Park, Maryland 20742.
authors: M J
authors: MJ
authors: Holden
authors: H
authors: H
authors: Sze