Die Photomodulation der Akkumulationsrate von Ascorbinsäure beim Senfkeimling (Sinapis albaL.) durch Phytochrom

摘要

Ascorbic acid accumulation in the mustard seedling is controlled byPfr(active phytochrome). Kinetic studies demonstrate thatPfrexerts a rapid and fully reversible control over the steady state rate of ascorbic acid accumulation. Following the terminology of Weisz (1967) for this type of metabolic control the term “photomodulation byPfr” is used.—The control byPfris independent of RNA synthesis. Therefore regulation of gene activity is probably not involved in photomodulation of the rate of ascorbic acid accumulation.—There is only a limited period within whichPfrcan control ascorbic acid accumulation. This period is fixed by the time pattern of “primary” differentiation in the seedling. There is no interaction between photomodulation byPfrand control by “primary” differentiation of ascorbic ac