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Published on: July 15, 2012
Coordination of Ca2+ signalling by NAADP
S Patel1, G C Churchill, A Galione
1Dept of Pharmacology, University of Oxford, Mansfield Road, OX1 3QT, Oxford, UK. sandip.patel@pharmacology.ox.ac.uk
Trends in Biochemical Sciences
|August 16, 2001
Summary
Nicotinic acid adenine dinucleotide phosphate (NAADP) mobilizes intracellular calcium stores. NAADP likely shapes cellular calcium signals by interacting with other calcium release pathways.
Area of Science:
- Cell Biology
- Biochemistry
- Physiology
Background:
- Nicotinic acid adenine dinucleotide phosphate (NAADP) is a potent intracellular calcium (Ca2+) mobilizer.
- NAADP-sensitive Ca2+ channels are distinct from those activated by inositol trisphosphate (IP3) and cyclic ADP-ribose (cADPR).
Purpose of the Study:
- To investigate the role of NAADP in shaping cytosolic Ca2+ signals.
- To explore the functional coupling between NAADP-mediated Ca2+ release and other pathways.
Main Methods:
- Studies were conducted in intact cells.
- Functional coupling ('channel chatter') between different Ca2+ release pathways was examined.
Main Results:
- NAADP mobilizes intracellular Ca2+ stores across various cell types.
- Evidence supports functional coupling between NAADP, IP3, and cADPR-mediated Ca2+ release pathways.
- This 'channel chatter' suggests complex regulation of cytosolic Ca2+ signals.
Conclusions:
- NAADP plays a significant role in regulating intracellular Ca2+ dynamics.
- The interplay between NAADP and other Ca2+ signaling pathways is crucial for cellular function.
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