Novel compartment implicated in calcium signaling--is it an "induced coupling domain"?
The endoplasmic reticulum (ER) is not simply a uniform continuous organelle, but is spatially and functionally heterogeneous with nonuniform distribution of endoplasmic Ca(2+)-handling proteins, such as Ca(2+)-binding proteins, Ca(2+) pumps, and Ca(2+)-release channels. Such nonuniform distribution of Ca(2+)-handling proteins is thought to create a spatially divided calcium store and to contribute to the generation of complex intracellular Ca(2+) dynamics. In addition to the particular distribution of these Ca(2+)-handling proteins within ER, extracellular stimuli may also stimulate the formation of dynamic new ER compartments containing Ca(2+)-handling proteins. These compartments containing Ca(2+)-handling proteins have potential roles in Ca(2+) signaling; specifically, they may function as "induced coupling domains" between the ER and plasma membrane, thereby allowing Ca(2+) entry into the ER.
Hisatsune
Chihiro
C
Laboratory for Developmental Neurobiology, RIKEN Brain Science Institute (BSI), 2-1 Hirosawa, Wako City, Saitama 351-0198, Japan.
Mikoshiba
Katsuhiko
K
D000818:Animals; D015220:Calcium Channels / Q000502:physiology; D020013:Calcium Signaling / Q000502:physiology*; D002451:Cell Compartmentation; D029721:Drosophila Proteins / Q000502:physiology; D004331:Drosophila melanogaster / Q000502:physiology; D004721:Endoplasmic Reticulum / Q000502:physiology* / Q000648:ultrastructure; D006801:Humans; D053496:Inositol 1,4,5-Trisphosphate Receptors; D008565:Membrane Proteins / Q000502:physiology; D046912:Multiprotein Complexes; D009363:Neoplasm Proteins / Q000502:physiology; D034622:RNA Interference; D018160:Receptors, Cytoplasmic and Nuclear / Q000502:physiology; D000071737:Stromal Interaction Molecule 1; D010738:Type C Phospholipases / Q000502:physiology
D015220:Calcium Channels; D029721:Drosophila Proteins; C506926:ITPR1 protein, human; D053496:Inositol 1,4,5-Trisphosphate Receptors; D008565:Membrane Proteins; D046912:Multiprotein Complexes; D009363:Neoplasm Proteins; D018160:Receptors, Cytoplasmic and Nuclear; C103530:STIM1 protein, human; C502662:Stim protein, Drosophila; D000071737:Stromal Interaction Molecule 1; D010738:Type C Phospholipases