Back in the water: The return of the inositol phosphates

Following the discovery of inositol-1,4,5-trisphosphate as a second messeng er, many other inositol phosphates were discovered in quick succession, wit h some understanding of their synthesis pathways and a few guesses at their possible functions. But then it all seemed to go comparatively quiet, with an explosion of interest in the inositol lipids. Now the water-soluble pha se is once again becoming a focus of interest. Old and new data point to a new vista of inositol phosphates, with functions in many diverse aspects of cell biology, such as ion-channel physiology, membrane dynamics and nuclea r signalling.