3- and 4-phosphorylated phosphatidylinositols in the aquatic plant Spirodela polyrhiza L.

摘要

Labelling of Spirodela polyrhiza L. plants with [3H]inositol and [32P]Pi yielded a series of phosphoinositides which were identified as PtdIns, PtdIns4P and PtdIns(4,5)P2. In addition, systematic degradation of a phospholipid extract identified PtdIns3P. Analysis of the distribution of 32P label between the monoester and diester phosphate groups of PtdIns3P and PtdIns4P revealed differences in the labelling of the monoester phosphate, suggesting that the two PtdInsP species are not synthesized or metabolized in a co-ordinate manner.