Early events in signalling high-temperature stress in tobacco BY2 cells involve alterations in membrane fluidity and enhanced hydrogen peroxide production.

Alterations in membrane fluidity are among the early events in plants that detect changes in ambient temperature. However, signal transduction downstream of the membrane-associated processes is still not well understood. We have focused here on the role of hydrogen peroxide (H(2)O(2)) in high-temperature signalling in relation to changes in membrane fluidity in cells of tobacco (Nicotiana tabacum L.

The effect of glucose on chloride uptake by Chlorella : II. Effect of intracellular acidification on chloride uptake.

Glucose at 5 mM inhibited chloride uptake by Chlorella fusca in the light and in the dark by 30±10% and acidified the cell interior by 0.2 units (measured with 5.5-dimethyl-oxazolidine-2.

The effect of glucose on chloride uptake by Chlorella : I. General characteristics of chloride transport.

Active Cl(-) uptake by Chlorella fusca was examined by using (36)Cl as a label. Under light/air conditions chloride influx from a 2.4·10(-5) M solution was 4.

The effect of the uncoupler carbonyl cyanide m-chlorophenylhydrazone on K+ transport, ATP level and intracellular pH of Chlorella fusca.

1. Low concentrations of the uncoupler carbonyl cyanide m-chlorophenylhydrazone (CCCP) induced net K+ uptake by Chlorella fusca, optimal concentrations being 3 microM CCCP in the light and 1 microM CCCP in the dark. Higher concentrations increasingly stimulated K+ release.

Influence of permeant acids and bases on net potassium uptake by Chlorella.

Salts of membrane-permeant acids and bases strongly influence net K uptake by Chlorella fusca. Na phenylacetate, acetate, isobutyrate, propionate, and butyrate added to buffered algal suspensions containing 0.1-0.