title: Ca(2+) signalling by IP(3) receptors.
abstract: The Ca(2)                         (+) signals evoked by inositol 1,4,5-trisphosphate (IP(3)) are built from elementary Ca(2)                         (+) release events involving progressive recruitment of IP(3) receptors (IP(3)R), intracellular Ca(2)                         (+) channels that are expressed in almost all animal cells. The smallest events ('blips') result from opening of single IP(3)R. Larger events ('puffs') reflect the near-synchronous opening of a small cluster of IP(3)R. These puffs become more frequent as the stimulus intensity increases and they eventually trigger regenerative Ca(2)                         (+) waves that propagate across the cell. This hierarchical recruitment of IP(3)R is important in allowing Ca(2)                         (+) signals to be delivered locally to specific target proteins or more globally to the entire cell. Co-regulation of IP(3)R by Ca(2)                         (+) and IP(3), the ability of a single IP(3)R rapidly to mediate a large efflux of Ca(2)                         (+) from the endoplasmic reticulum, and the assembly of IP(3)R into clusters are key features that allow IP(3)R to propagate Ca(2)                         (+) signals regeneratively. We review these properties of IP(3)R and the structural basis of IP(3)R behavior.
authors.affiliation: Department of Pharmacology, Tennis Court Road, CB2 1PD, Cambridge, UK, cwt1000@cam.ac.uk.
authors.forename: Colin W
authors.initials: CW
authors.lastname: Taylor
authors.forename: David L
authors.initials: DL
authors.lastname: Prole
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism*; D020013:Calcium Signaling; D005057:Eukaryotic Cells / Q000378:metabolism*; D005786:Gene Expression Regulation; D006801:Humans; D015544:Inositol 1,4,5-Trisphosphate / Q000378:metabolism*; D053496:Inositol 1,4,5-Trisphosphate Receptors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015640:Ion Channel Gating; D017136:Ion Transport; D008958:Models, Molecular; D011485:Protein Binding
chemical_list: D053496:Inositol 1,4,5-Trisphosphate Receptors; D015544:Inositol 1,4,5-Trisphosphate; D002118:Calcium