Possible roles of inositol 1,4,5-trisphosphate 3-kinase B in calcium homeostasis.

Some aspects of the roles of inositol trisphosphate (Insp3) and inositol tetrakisphosphate (Insp4) in Ca2+ homeostasis in terms of inositol trisphosphate 3-kinase B (IP3K-B) localization and activity are discussed. The model that we propose is also compatible with IP3K-B participating in the widely reported phenomenon of quantal release of Ca2+ from internal stores, at least in some biological systems.