ศูนย์นวัตกรรมเทคโนโลยีหลังการเก็บเกี่ยว

Characterization of carbon dioxide stress-induced ethylene biosynthesis in cucumber (Cucumis sativus L.) fruit.

Mathooko, F. M.; Inaba, A.; Nakamura, R.;

Plant and Cell Physiology Year: 1998 Vol: 39 Issue: 3 Pages: 285-293 Ref: 46 ref.

1998

บทคัดย่อ

Carbon dioxide-induced ethylene biosynthesis was investigated in cucumber cv. Sharp 1 fruits. A series of inhibitors were tested to determine the involvement of de novo protein synthesis, new mRNA synthesis, protein kinase activity, and phosphoprotein phosphatase activity in CO2 stress-induced ethylene biosynthesis. CO2 stimulated ethylene production through the induction of 1-aminocyclopropane-1-carboxylate (ACC) synthase and ACC oxidase activities. Induction of ACC synthase activity led to ACC accumulation. Cycloheximide blocked CO2 stress-induced ethylene biosynthesis, whereas cordycepin had no effect. Dibucaine and 6-dimethylaminopurine, inhibitors of protein kinases, blocked CO2 stress-induced increases in ethylene production, ACC synthase activity, and ACC content, but did not block the increase in ACC oxidase activity. Cantharidin, a potent inhibitor of protein phosphatase type 1 and type 2A, stimulated CO2 stress-induced ethylene production, ACC synthase activity, and ACC accumulation, b

ut had no additional effect on CO2 stress-induced ACC oxidase activity. In the presence of dibucaine or cycloheximide, the stimulation of CO2 stress-induced ethylene biosynthesis by cantharidin was blocked. It is suggested that CO1 stress-induced ethylene biosynthesis may be regulated post-transcriptionally, and that induction involves the synthesis of novel protein(s) in the cytosol. The results identify protein phosphorylation and dephosphorylation as requirements in one or more of the steps involved in the CO2 signal transduction pathway that leads to induction of ethylene biosynthesis, and in particular, to the induction of ACC synthase, presumably the key enzyme in the ethylene biosynthetic pathway.