Boron is required for the stimulation of the ferricyanide‐induced proton release by auxins in suspension‐cultured cells of Daucus carota and Lycopersicon esculentum

Abstract

Boron deficiency reduces the ferricyanide‐induced net proton release of suspension‐cultured carrot (Daucus carota L.) and tomato (Lycopersicon esculentum Mill.) cells by more than 50%. This effect is reversed within 60 to 90 min by the addition of B. Vanadate (400 μM) completely suppresses the proton release, indicating an ATPasedriven process. The differences between B treatments do not appear when auxins are omitted from the experimental solution, but can be observed within less than 30 min after the addition of auxin to auxin‐deficient cell cultures. This suggests, that an adequate supply of B is required for the auxin action to take place. The results are discussed with respect to the primary functions of B in membranes and transport processes, and its possible influence on auxin‐induced metabolic events.

Body Weight Reducing Effect of Oral Boric Acid Intake

“…Lots of studies have shown that supplemental boron stimulates proton pumping in plants, causes hyperpolarization of the membrane potential, and increases potassium uptake. Along with these findings, there have been reports of a boron-mediated increase in ferricyanide reduction 19 - 22 . There is also strong evidence that boron is involved in lignin biosynthesis and in cell wall cross-linking in plants 23 .…”

Glycosylinositol phosphorylceramides from Rosa cell cultures are boron‐bridged in the plasma membrane and form complexes with rhamnogalacturonan II

“…Much evidence suggests that B also plays a role in the structure and function of the plant plasma membrane ( Loomis and Durst, 1992 ; Blevins and Lukaszewski, 1998 ). Within minutes, B deprivation inhibits P i and Rb + uptake ( Pollard et al ., 1977 ; Goldbach, 1985 ) and ferricyanide-induced H + release ( Goldbach et al ., 1990 ), suggesting that B does not act only by maintaining wall integrity. Withholding B also causes visible abnormalities at the wall–membrane interface and is likely to be involved in the organisation of transvacuolar cytoplasmic strands and/or to participate in wall–membrane attachment ( Hirsch and Torrey, 1980 ; Bassil et al ., 2004 ).…”

Effects of Boron on Growth, and Chlorophyll and Mineral Contents of Shoots of the Apple Rootstock MM 106 cultured in vitro

“…In contrast, in our experiments higher B concentrations in the culture medium (> 0.1 mM) exerted a negative effect on the plasma membrane properties of explants and thus decreased K + uptake. In addition, B might influence plant reactions to environmental stimuli by modifying their response to auxins (Goldbach et al 1990).…”