Subcellular Localization of Zinc and Calcium in Bean (Phaseolus vulgaris L.) Tissues

Abstract

Two bean (Phaseolus vulgaris L.) cultivars differing in growth responses to zinc were examined for differences in uptake and subcellular localization of 0Zn during a 15-day growth period. The zinc-sensitive cultivar Sanilac showed initially a much higher rate of absorption, which declined after 24 hours. The zinc-tolerant cultivar Saginaw showed a slow but steady rate of absorption for 10 days. In roots as well as in stem callus tissues of both cultivars, three-fourths of the absorbed "5Zn was localized in the "cytoplasmic" supernatant fractions (containing ribosomes and vacuolar sap). Very little (less than 7%) "Zn was localized in the cell wall fraction. There was a much greater proportion of the absorbed "Zn localized in root mitochondria and nuclei of the zinc-sensitive Sanilac than in the zinc-tolerant Saginaw. Stem The intracellular localization of enzymes in plant tissues has received wide attention (2,4,6,8,11,15,16,18,20

Exclusion of metals from the symplasm: A possible mechanism of metal tolerance in higher plants

“…Rathore et jil_. (48) found less than 7% of total root Zn was localized in"tn~e cell wall fractions of Zn-tolerant and Zn-sensitive Phaseolus vulgaris. Godbold et jil_.…”

The role of calcium in regulating alginate-derived oligosaccharides in nitrogen metabolism of Brassica campestris L. var. utilis Tsen et Lee

“…Fresh leaves (samples weighing approximately 0.5 g) were washed twice with deionized water and homogenized manually in a pre-cooling homogenizing solution in a mortar as described by Rathore et al (1972). The homogenizing solution contained 0.25 mM sucrose, 50 mM Tris-maleate buffer (pH 7.8), 1 mM MgCl 2 , and 10 mM cysteine.…”

Synergistic effects of arbuscular mycorrhizal fungi and phosphate rock on heavy metal uptake and accumulation by an arsenic hyperaccumulator

“…Part of the plant sample was used to study subcellular As distribution while the other part was used to determine the total As concentration. Subcellular distributions of As were determined according to the methods described by Hans and Pathore et al [50,51]. Samples were homogenized in pre-cooled homogenized solution (0.25 mmol l −1 sucrose, 50 mmol l −1 Tris-maleate buffer) and 1 mmol l −1 MgCl 2 .…”