Understanding inositol pyrophosphate metabolism and function: Kinetic characterization of the DIPPs.

Highlights: [•] Understanding inositol pyrophosphate turnover through kinetic study of Ddp1p/DIPPs. [•] k cat values for 1-InsP7 are 5–20-fold higher than those for 5-InsP7 and InsP8. [•] InsP7 does not regulate CDK5, the human homologue of the yeast Pho85 cyclin kinase. [•] Kinetics imply differential expression of DIPP isoforms sets signaling sensitivity. [•] Metabolically and functionally separate routes for InsP8 synthesis and hydrolysis. [ABSTRACT FROM AUTHOR]