(22S,23S)-Homobrassinolide was tested for its effect on the electric cell potential, proton extrusion, ferricyanide reduction, and amino acid and sucrose uptake of leaves of Egeria densa Planchon. In the light, (22S,23S)-homobrassinolide and its derivative, 2alpha-3alpha-dihydroxy-5alpha-stigmast-22-en-6-one, were similar to each other and similar to fusicoccin in causing hyperpolarization and ...

Chemically induced dimerization is an important tool in chemical biology for the analysis of protein function in cells. Here we report the use of the natural product fusicoccin (FC) to induce dimerization of 14-3-3-fused target proteins with proteins tagged to the C terminus (CT) of the H(+)-ATPase PMA2. To prevent nonproductive or detrimental interactions of the 14-3-3 proteins and CT fusions ...

Symbiotic dinitrogen fixation of legume nodules is fuelled by phloem-imported carbohydrates. These have to pass several cell layers to reach cells infected with Rhizobium bacteroids. It is unclear whether apoplastic steps are involved in carbohyd-rate translocation within the nodule. Protoplasts were isolated from the infected and uninfected cells of the central tissue of Vicia faba nodules usi...

Expansins are wall proteins that mediate a type of acid-induced extension in isolated plant cell walls (S. McQueen-Mason, D.M. Durachko, D.J. Cosgrove [1992] Plant Cell 4: 1425-1433). To assess the role of these proteins in the process of cell enlargement in living tissues, we compared the spatial and temporal growth patterns of oat (Avena sativa L.) coleoptiles with four wall properties relate...

The cytoplasmic pH of growing pollen tubes of Lilium longiflorum Thunb. was measured using the pH-sensitive fluorescent dye 2',7'-bis-(carboxyethyl)-5(6')-carboxyfl uorescein and confocal fluorescence ratio imaging. The average cytoplasmic pH in the clear zone of the pollen tube tip was pH 7.11, and no consistent pH gradients were detected in the clear zone, averaging around -1.00 milli pH unit...