Inositol 1,4,5 trisphosphate (IP3) receptor.
The intensive molecular and biochemical study of IP(3)R has made great progress in elucidating the following unique properties of IP(3)R: 1) IP(3) dependent Ca(2+) release is quantal in nature; 2) IP(3)R allosterically and dynamically changes its form; 3) IP(3)R is functional even though it is fragmented by proteases into several pieces; 4) IP(3)R forms a functional association with a variety of molecules inside the cell, and with the channels on the plasma membrane; 5) the extremely high IP(3) binding affinity (500 approximately 1000 times higher than the original IP(3)R) sequence in the IP(3) binding region is covered with a suppressor sequence at the N-terminal. In parallel with these biochemical studies, studies on the role of IP(3)R during development have greatly advanced. Since IP(3)R was identified as a developmentally regulated phospho-glycoprotein, the Ca(2+) channel P400, it has diverse but essential functions in development and normal cell function.
Mikoshiba
Katsuhiko
K
The Institute of Medical Science, The University of Tokyo, Japan. mikosiba@ims.u-tokyo.ac.jp
D000818:Animals; D002118:Calcium / Q000378:metabolism; D015220:Calcium Channels / Q000502:physiology*; D020013:Calcium Signaling / Q000502:physiology; D002147:Calmodulin / Q000502:physiology; D053496:Inositol 1,4,5-Trisphosphate Receptors; D051379:Mice; D018160:Receptors, Cytoplasmic and Nuclear / Q000502:physiology*
D015220:Calcium Channels; D002147:Calmodulin; D053496:Inositol 1,4,5-Trisphosphate Receptors; D018160:Receptors, Cytoplasmic and Nuclear; D002118:Calcium