How do inositol phosphates regulate calcium signaling?

FASEB J. 1989 Jun;3(8):1899-905. doi: 10.1096/fasebj.3.8.2542110.


Activation of a variety of cell surface receptors results in the phospholipase C-catalyzed hydrolysis of the minor plasma membrane phospholipid phosphatidylinositol 4,5-bisphosphate, with concomitant formation of inositol 1,4,5-trisphosphate and diacylglycerol. There is strong evidence that inositol 1,4,5-trisphosphate stimulates Ca2+ release from intracellular stores. The Ca2+-releasing actions of inositol 1,4,5-trisphosphate are terminated by its metabolism through two distinct pathways. Inositol 1,4,5-trisphosphate is dephosphorylated by a 5-phosphatase to inositol 1,4-bisphosphate; alternatively, inositol 1,4,5-trisphosphate can also be phosphorylated to inositol 1,3,4,5-tetrakisphosphate by a 3-kinase. Although the mechanism of Ca2+ mobilization is understood, the precise mechanisms involved in Ca2+ entry are not known; the proposal that inositol 1,4,5-trisphosphate secondarily elicits Ca2+ entry by emptying an intracellular Ca2+ pool is considered.

Publication types

  • Review

MeSH terms

  • Animals
  • Calcium / metabolism*
  • Calcium Channels*
  • Cell Membrane / metabolism
  • Humans
  • Inositol 1,4,5-Trisphosphate
  • Inositol 1,4,5-Trisphosphate Receptors
  • Inositol Phosphates / metabolism*
  • Phosphorylation
  • Receptors, Cell Surface / metabolism
  • Receptors, Cytoplasmic and Nuclear*
  • Signal Transduction*
  • Sugar Phosphates / metabolism*
  • Type C Phospholipases / metabolism


  • Calcium Channels
  • ITPR1 protein, human
  • Inositol 1,4,5-Trisphosphate Receptors
  • Inositol Phosphates
  • Receptors, Cell Surface
  • Receptors, Cytoplasmic and Nuclear
  • Sugar Phosphates
  • Inositol 1,4,5-Trisphosphate
  • Type C Phospholipases
  • Calcium