Reactions of corn root tissue to calcium

Journal Article · Sun Jan 01 04:00:00 EST 1984 · Plant Physiol. (Engl. Transl.); (United States)

DOI:https://doi.org/10.1104/pp.76.2.403· OSTI ID:5004563

de Quintero, M R; Hanson, J B

Washing corn (Zea mays L.) root tissue in water causes loss of about one-third of the exchangeable Ca/sup 2 +/ over the first 10 to 15 minutes. Upon transfer to K/sup +/-containing solutions, the tissue shows a short period of rapid K/sup +/ influx which subsequently declines. Addition of 0.1 millimolar Ca/sup 2 +/ decreases the initial rapid K/sup +/ influx, but increases the sustained rate of K/sup +/ and Cl/sup -/ uptake. It was confirmed that 0.1 millimolar Ca/sup 2 +/ is more effective than higher concentrations for the initial inhibition, and that Mg/sup 2 +/ will substitute. The inhibition arises from a mild shock affect of restoring Ca/sup 2 +/. With 0.1 millimolar Ca/sup 2 +/ net H/sup +/ efflux is blocked for 10 to 15 minutes and the cells are depolarized by about 30 millivolts. However, 1 millimolar Ca/sup 2 +/ rapidly produces increased K/sup +/ influx and blocks net H/sup +/ efflux for only a few minutes; blockage is preceded by a brief net H/sup +/ influx which may restore and increase ion transport by reactivating the plasmalemma H/sup +/-ATPase. Stimulation of electrogenic H/sup +/-pumping with fusicoccin eliminates the shock responses and minimizes Ca/sup 2 +/ effects on K/sup +/ influx. Fusicoccin also strongly decreases Ca/sup 2 +/ influx, but has no effect on Ca/sup 2 +/ efflux. Ice temperatures and high pH decreased Ca/sup 2 +/ efflux, but uncoupler and chlorpromazine did not. It is suggested that the inhibitory and promotive actions of Ca/sup 2 +/ are manifested through decreases or increases in the protonmotive force. 29 references, 11 figures, 1 table.

• Research Organization: Univ. of Illinois, Urbana
• DOE Contract Number: AC02-76EV00790
• OSTI ID: 5004563
• Journal Information: Plant Physiol. (Engl. Transl.); (United States), Journal Name: Plant Physiol. (Engl. Transl.); (United States) Vol. 76; ISSN PPHYA
• Country of Publication: United States
• Language: English

Related Subjects

560303* -- Chemicals Metabolism & Toxicology-- Plants-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ACID ANHYDRASES
ALKALI METAL COMPOUNDS
ALKALINE EARTH METAL COMPOUNDS
ATP-ASE
BIOLOGICAL EFFECTS
BODY
CALCIUM COMPOUNDS
CATIONS
CEREALS
CHARGED PARTICLES
ELECTROPHYSIOLOGY
ENZYME ACTIVITY
ENZYMES
GRASS
HYDROGEN IONS
HYDROGEN IONS 1 PLUS
HYDROLASES
IONS
MAIZE
MEMBRANE TRANSPORT
PHOSPHOHYDROLASES
PHYSIOLOGY
PLANT TISSUES
PLANTS
POTASSIUM COMPOUNDS
ROOTS
TISSUES
UPTAKE