Molecule s of Interest myo - Inositol - 1 , 2 , 3 , 4 , 5 , 6 - hexa kis phosphate

myo-Inositol-1,2,3,4,5,6-hexakisphosphate (Ins P6) was first described as an abundant form of phosphorus in plant seeds and other plant tissues and dubbed ‘‘phytic acid’’. Subsequently it was found to be a common constituent in eukaryotic cells, its metabolism a basic component of cellular housekeeping. In addition to phosphate, myo-inositol (Ins) and mineral storage and retrieval in plant organs and tissues, other roles for Ins P6 include service as a major metabolic pool in Ins phosphate and pyrophosphate pathways involved in signaling and regulation; possibly as an effector or ligand in these processes; as a form of energy currency and in ATP regeneration; in RNA export and DNA repair; and as an anti-oxidant. The relatively recent demonstration that pyrophosphate-containing derivatives of Ins P6 can function as phosphate donors in the regeneration of ATP is reminiscent of the proposal, made four decades ago in studies of seed development, that Ins P6 itself may serve in this function. Studies of Ins P6 in non-plant systems rarely include the consideration that this compound might represent a significant fraction of cellular P; cellular phosphate nutrition has been viewed as either not interesting or of little importance. However, there may be few fundamental differences among diverse eukaryotes in both the metabolic pathways involving Ins P6 and the spectrum of possible roles for it and its metabolites. Published by Elsevier Ltd.