Abstract
Pondweed (Potamogeton distinctus A.Benn.) displays tolerance to anoxia. Elongation of overwintered turions is promoted by oxygen-free conditions, and it is influenced by chemicals which have effects on a plasma membrane (PM) H+-ATPase, suggesting that PM H+-ATPase plays an important role in survival under anoxic conditions. We examined the activity of PM H+-ATPase, its protein amounts, and phosphorylation levels of the domain binding 14-3-3 proteins in pondweed turions and etiolated hypocotyls of pea (Pisum sativum) which cannot survive over one day in anoxia. In pondweed turions, the PM H+-ATPase activity and its phosphorylation levels were maintained under anoxia. On the other hands, both fusicoccin and okadaic acid, which promoted PM H+-ATPase activity, had slightly promotive effects on survival of pea hypocotyls under anoxia, suggesting that a role of PM H+-ATPase is important for anoxic tolerance of plant cells.
