FLUORIDE-INDUCED INHIBITION OF STARCH BIOSYNTHESIS IN DEVELOPING POTATO, SOLANUM-TUBEROSUM L, TUBERS IS ASSOCIATED WITH PYROPHOSPHATE ACCUMULATION

被引:18
作者
VIOLA, R
DAVIES, HV
机构
[1] Department of Cellular Physiology, Scottish Crop Research Institute, Invergowrie
关键词
D O I
10.1104/pp.97.2.638
中图分类号
Q94 [植物学];
学科分类号
071001 ;
摘要
Pretreatment of discs excised from developing tubers of potato (Solanum tuberosum L.) with 10 millimolar sodium fluoride induced a transient increase in 3-phosphoglycerate content. This was followed by increases in triose-phosphate, fructose 1,6-bisphosphate and hexose-phosphate (glucose 6-phosphate + fructose 6-phosphate + glucose 1-phosphate). The effect of fluoride is attributed to an inhibition of glycolysis and a stimulation of triose-phosphate recycling (the latter confirmed by the pattern of C-13-labeling [NMR] in sucrose when tissue was supplied with [2-C-13]glucose). Fluoride inhibited the incorporation of [U-C-14] glucose, [U-C-14]sucrose, [U-C-14]glucose 1-phosphate, and [U-C-14] glycerol into starch. The incorporation of [U-C-14]ADPglucose was unaffected. Inhibition of starch biosynthesis was accompanied by an almost proportional increase in the incorporation of C-14 into sucrose. The inhibition of starch synthesis was accompanied by a 10-fold increase in tissue pyrophosphate (PPi) content. Although the subcellular localization of PPi was not determined, a hypothesis is presented that argues that the PPi accumulates in the amyloplast due to inhibition of alkaline inorganic pyrophosphatase by fluoride ions.
引用
收藏
页码:638 / 643
页数:6
相关论文
共 32 条