Post-genome analysis of plant intact vacuole

Abstract

Vacuole plays an important role in maintaining the homeostasis of plant cells, that is, the maintenance of the turgor pressure, the accumulation of inorganic ions and metabolites and the degradation of discarded proteins. These functions of the vacuole predict that the vacuole include many kind of substances. We have analyzed contents of intact vacuoles directly and comprehensively by using CE-MS and FT-ICR-MS. There are organic phosphate compounds in the vacuole irrespective that the vacuole includes phosphatase. The proteomic analysis of vacuolar membrane and vacuolar sap was also conducted. Relationship between proteins and metabolites in the vacuole is discussed. We have overexpressed the unknown tonoplast proteins of Arabidopsis suspension-cultured cells whose function are unknown. We will report the comparative analysis of the vacuolar metabolites of the wild-type and transgenic cells.