ISSN:
1399-3054
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Biology
Notes:
The effects of external K+, H+ and Ca2+ concentrations on the intracellular K+ concentration, [K+]i, and the K+-ATPase activity in 2-day-old mung bean roots [Vigna mungo (L.) Hepper] were investigated. [K+]i, in mung bean roots was markedly decreased by external K+ or H+ stress and did not recover the initial value even after the stress was removed. This decrease in [K+]i, gradually disappeared with the addition of (Ca2+. Ca2+ may offset the harmful effects of ion stress. Ca2+ seems to have two effects on K+ transport; control of K+ permeability and activation of K+ uptake, although K+-ATPase activity was inhibited by Ca2+ concentrations higher than 10–4 M. We suggest that Ca2+ activates K+ uptake indirectly through the acidification of the cytoplasm.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1399-3054.1985.tb04260.x
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