New molecular players in capacitative Ca2+ entry.
Capacitative Ca2+ entry links the emptying of intracellular Ca2+ stores to the activation of store-operated Ca2+ channels in the plasma membrane. In the twenty years since the inception of the concept of capacitative Ca2+ entry, a number of activation mechanisms have been proposed, and there has been considerable interest in the possibility that TRP channels function as store-operated channels. However, in the past two years, two major players in both the signaling and permeation mechanisms for store-operated channels have been discovered: Stim1 and the Orai proteins. Stim1 is an endoplasmic reticulum Ca2+ sensor. It appears to act by redistributing within a small component of the endoplasmic reticulum, approaching the plasma membrane, but does not seem to translocate into the plasma membrane. Stim1 signals to plasma membrane Orai proteins, which constitute pore-forming subunits of store-operated channels.
Putney
James W
JW
National Institute of Environmental Health Sciences - NIH, PO Box 12233, Research Triangle Park, NC 27709, USA. putney@niehs.nih.gov
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D020013:Calcium Signaling / Q000502:physiology*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism; D004331:Drosophila melanogaster; D025802:Electric Capacitance; D004791:Enzyme Inhibitors / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D000071740:ORAI1 Protein; D000071737:Stromal Interaction Molecule 1; D019284:Thapsigargin / Q000378:metabolism; D050051:Transient Receptor Potential Channels / Q000235:genetics / Q000378:metabolism
D029721:Drosophila Proteins; D004791:Enzyme Inhibitors; D008565:Membrane Proteins; D000071740:ORAI1 Protein; C502662:Stim protein, Drosophila; D000071737:Stromal Interaction Molecule 1; D050051:Transient Receptor Potential Channels; C510747:olf186-F protein, Drosophila; D019284:Thapsigargin; D002118:Calcium