Cerulenin has been used to investigate the mechanism by which leaf strips ofCentranthus ruber(L.) Lam et D.C. increase their capacity for solute uptake during a period of incubation in CaSO4(“aging”). α-Aminoisobutyric acid was used to assess uptake capability. The leaf strips developed their uptake capacity for at least 8–10 h after excision. Cerulenin, if added to the aging medium immediately after cutting or at any time during the aging process, almost completely halted this development, but did not bring about loss of the uptake capacity already achieved. That cerulenin was specifically interfering with fatty-acid biosynthesis was indicated by the fact that it drastically depressed incorporation of labelled acetate into the lipid fraction but did not affect the incorporation of labelled alanine. Cycloheximide strongly inhibited the development of uptake capacity, but sensitivity to actinomycin D was not evident for at least 2 h. The results are consistent with the concept that slicing leads to immediate damage to tissue membranes and that “aging” is a process of membrane repair, involving renewed synthesis of membrane lipids and membran
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