Ethylene-Mediated Phospholipid Catabolic Pathway in Glucose-Starved Carrot Suspension Cells

다국어 초록 (Multilingual Abstract)

Clurose (Glc) starvation of suspension-cultured carrot (Daucus carota L.) celIs resulted in sequential activation of phospholipid catabolic enzymes. Among the assayed enzymes involved in the degradation, phospholipas D (PLD) and lipolytic acyl hydrolase were activated at the early part of starvation, and these activities were followed by ?-oxidation and the glyoxylate cyrle enzymer in order. The activity of PLD and lipolytic acyl hydrolase was further comfirmed by in vivo-labeling experiments. It was demonstrated that Glc added to a medium containing starving cells inhibited the phospholipid catabolir activities, indicating that phospholipid catabolism is negatively regulated by Glc. There was a burst of ethylene production 6 h after starvation. Ethylene added exogeneously to a Glc-sufficient medium activated PLD, indicating that ethylene acts as an element in the signal transduction pathway leading from Glc depletion to PLD activation. Activation of lipid peroxidation, suggestive of cell death, occurred immediately after the decrease of the phospholipid degradation, suggesting that the observed phospholipid catabolic pathway is part of the metabolic strategies by which cells effectively survive under Glc starvation.

목차 (Table of Contents)

• 1.Abstracts
• 2.MATERIALS AND METHODS
• 3.RESULTS
• 4.DISCUSSION
• 5.ACKNOWLEDGMENTS
• 6.LITERATURE CITED