Inositol 1,4,5-trisphosphate receptors as signal integrators.
The inositol 1,4,5 trisphosphate (IP3) receptor (IP3R) is a Ca2+ release channel that responds to the second messenger IP3. Exquisite modulation of intracellular Ca2+ release via IP3Rs is achieved by the ability of IP3R to integrate signals from numerous small molecules and proteins including nucleotides, kinases, and phosphatases, as well as nonenzyme proteins. Because the ion conduction pore composes only approximately 5% of the IP3R, the great bulk of this large protein contains recognition sites for these substances. Through these regulatory mechanisms, IP3R modulates diverse cellular functions, which include, but are not limited to, contraction/excitation, secretion, gene expression, and cellular growth. We review the unique properties of the IP3R that facilitate cell-type and stimulus-dependent control of function, with special emphasis on protein-binding partners.
Patterson
Randen L
RL
Department of Neuroscience, Johns Hopkins University, Johns Hopkins Medical School, Baltimore, Maryland 21205, USA. rpatter1@jhmi.edu
Boehning
Darren
D
Snyder
Solomon H
SH
D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D017209:Apoptosis / Q000502:physiology; D015220:Calcium Channels / Q000737:chemistry / Q000378:metabolism*; D020013:Calcium Signaling; D002135:Calcium-Binding Proteins / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D053496:Inositol 1,4,5-Trisphosphate Receptors; D046911:Macromolecular Substances; D008954:Models, Biological; D008958:Models, Molecular; D010766:Phosphorylation; D011487:Protein Conformation; D018160:Receptors, Cytoplasmic and Nuclear / Q000737:chemistry / Q000378:metabolism*; D015398:Signal Transduction; D022061:Tacrolimus Binding Protein 1A / Q000737:chemistry / Q000378:metabolism
D015220:Calcium Channels; D002135:Calcium-Binding Proteins; C506926:ITPR1 protein, human; D053496:Inositol 1,4,5-Trisphosphate Receptors; D046911:Macromolecular Substances; D018160:Receptors, Cytoplasmic and Nuclear; D000255:Adenosine Triphosphate; D022061:Tacrolimus Binding Protein 1A