SODIUM POTASSIUM ROOT DEFECTIVE1 (NaKR1; previously called NPCC6) encodes a soluble metal binding protein that is specifically expressed in companion cells of the phloem. The nakr1-1 mutant phenotype includes high Na(+), K(+), Rb(+), and starch accumulation in leaves, short roots, late flowering, and decreased long-distance transport of sucrose. Using traditional and DNA microarray-based deleti...

In order to study of the effect of priming and salinity on physiological and chemical characteristics of wheat(Triticum aestivum L.), an experiment was carried out at the Experimental Farm of Shiraz University. Results showedthat primed plants significantly reduced its gas exchanges by accelerating senescence under a series of salt stress,which became more serious along with the increasing of s...

Here, we show that the Na/K-ATPase interacts with caveolin-1 (Cav1) and regulates Cav1 trafficking. Graded knockdown of Na/K-ATPase decreases the plasma membrane pool of Cav1, which results in a significant reduction in the number of caveolae on the cell surface. These effects are independent of the pumping function of Na/K-ATPase, and instead depend on interaction between Na/K-ATPase and Cav1 ...

Several hormones and cytokines stimulate the cellular Na+/H+ antiporter and this stimulation may be a signal transduction mechanism to mediate gene expression. We find that tumor necrosis factor rapidly stimulates both the Na+/H+ antiporter and the accumulation of mRNA coding for granulocyte-macrophage colony-stimulating factor and interleukin-6 in fibroblasts. Further experiments show that the...

Chloride (Cl-) is an essential micronutrient for plant growth, but can be toxic at high concentrations resulting in reduced growth and yield. Although saline soils are generally dominated by both sodium (Na+) and Cl- ions, compared to Na+ toxicity, very little is known about physiological and genetic control mechanisms of tolerance to Cl- toxicity. In hydroponics and field studies, a bread whea...

The effects of cryoextraction on transport characteristics of rabbit lenses were evaluated by measuring Na+ and Ca++ levels, initial rates of 86Rb accumulation, and bioelectric potentials. The results demonstrate that membrane damage results from cryoextraction and is partially reversible during subsequent culture. While the decline in potential often exceeds 30 mV, maximum recovery of 80% occu...

Decoding of fast cytosolic Ca(2+) concentration ([Ca(2+)](i)) transients by mitochondria was studied in permeabilized cat ventricular myocytes. Mitochondrial [Ca(2+)] ([Ca(2+)](m)) was measured with fluo-3 trapped inside mitochondria after removal of cytosolic indicator by plasma membrane permeabilization with digitonin. Elevation of extramitochondrial [Ca(2+)] ([Ca(2+)](em)) to >0.5 microM res...

Potassium ion and Na(+) influx and efflux rates into and from excised barley roots are compared with the maximum capacity of accumulation. Potassium ion and Na(+) influx and efflux involve a cation exchange that is independent of simultaneous exchange of the accompanying anion. These exchange fluxes depend on the concentration and cation composition of the solutions from which they originate. S...

Selenium toxicity was investigated in cultured rabbit lenses to provide further information about the role of Ca++ in Se cataract. At a dose of 0.1 mM for 20 hr, Se induces a 10% change in Na levels within 6 hr, a 30% increase after 20 hr, and a three-fold increase within 48 hr of subsequent culture after removal of Se. In contrast, Ca++ levels remained normal throughout the first 24 hr. Only a...

To date, no gene expression comparisons have been conducted between highly salt tolerant halophytes and related glycophytes. Therefore, I investigated the effects of salinity on ion accumulation and expression of candidate salt tolerance genes in the highly tolerant salt accumulating halophyte Salicornia dolichostachya and the taxonomically related glycophytic Spinacia oleracea. S. dolichostach...