Inositol pyrophosphate messengers regulate arbuscular mycorrhizal symbiosis and phosphate uptake in Lotus japonicus.

Inositol pyrophosphates (PP-InsPs) are key nutrient messengers in plants, but their protein receptors remain poorly defined. Using a systems-level affinity screen with biotinylated InsP₆, InsP₇, and I...

Inositol pyrophosphates (PP-InsPs) are highly phosphorylated signaling molecules that regulate diverse cellular processes, including phosphate homeostasis and energy metabolism across species. Despit...

Inositol phosphates control many central processes in eukaryotic cells including nutrient availability, growth, and motility. Kinetic resolution of a key modulator of their signaling functions, the turnover of the phosphate groups on the inositol ring, has been hampered by slow uptake, high dilution, and constraining growth conditions in radioactive pulse-labeling approaches. Here, we demonstrate a rapid (seconds to minutes) and nonradioactive labeling strategy of inositol polyphosphates through 18O-water in yeast, human cells, and amoeba, which can be applied in any media. In combination with capillary electrophoresis and mass spectrometry, 18O-water labeling simultaneously dissects the in vivo phosphate group dynamics of a broad spectrum of even rare inositol phosphates. The good temporal resolution allowed us to discover vigorous phosphate group exchanges in some inositol polyphosphates and pyrophosphates, whereas others remain remarkably inert. We propose a model in which the biosynthetic pathway of inositol polyphosphates and pyrophosphates is organized in distinct, kinetically separated pools. While transfer of compounds between those pools is slow, each pool undergoes rapid internal phosphate cycling. This might enable the pools to perform distinct signaling functions while being metabolically connected.

Inositol pyrophosphates (PP-InsPs) are central regulators of eukaryotic signaling events. While certain PP-InsP isomers have been conclusively linked to the regulation of phosphate homeostasis throug...

Maize big embryo mutants reveal that inositol phosphate signaling controls embryo size.

Voigt et al. show that the 5′-inositol phosphatase gene inppl1a drives notochord expansion independent of vacuole fusion. Defects in notochord expansion are exacerbated by locomotion, causing more sev...

A noncanonical pathway of DELLA regulation by a conserved inositol pyrophosphate synthase was identified in the liverwort, Marchantia polymorpha, that lacks the canonical gibberellin-induced DELLA deg...

Inositol (pyro)phosphates represent a vital class of intracellular messengers that govern multiple biological processes. The last decade has experienced a surge of interest in the functions of this c...