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Interactions between calcium release pathways: multiple messengers and multiple stores
1Department of Pharmacology, Oxford University, Mansfield Road, OX1 3QT, Oxford, UK. antony.galione@pharm.ox.ac.uk
Cell Calcium
|January 25, 2003
Summary
Cyclic adenosine diphosphate ribose (cADPR) and nicotinic acid adenine dinucleotide phosphate (NAADP) are key calcium (Ca2+) messengers. They work with myo-inositol 1,4,5-trisphosphate (IP3) to generate complex Ca2+ signaling patterns in cells.
Area of Science:
- Cellular Biology
- Biochemistry
- Physiology
Background:
- Calcium ions (Ca2+) are crucial intracellular messengers.
- Complex Ca2+ signaling patterns are generated by various molecules.
- Cyclic adenosine diphosphate ribose (cADPR) and nicotinic acid adenine dinucleotide phosphate (NAADP) have emerged as significant Ca2+ releasing messengers.
Purpose of the Study:
- To review the roles of cADPR and NAADP in Ca2+ signaling.
- To discuss the interplay between different Ca2+ messengers and release channels.
- To explore how cells generate distinct Ca2+ signaling signatures.
Main Methods:
- Literature review of Ca2+ signaling mechanisms.
- Analysis of the distinct structures and functions of cADPR, NAADP, and IP3.
- Examination of Ca2+ release channels (e.g., RYRs) and Ca2+ stores (e.g., ER, acidic granules).
Main Results:
- cADPR enhances ryanodine receptor sensitivity, prolonging Ca2+ signals via Ca2+-induced Ca2+ release (CICR).
- NAADP triggers local Ca2+ signals from acidic stores, which can be amplified by CICR.
- IP3 and cADPR mobilize Ca2+ from the endoplasmic reticulum, while NAADP acts on different stores.
Conclusions:
- Multiple Ca2+ mobilizing messengers (cADPR, NAADP, IP3) and Ca2+ stores contribute to specific Ca2+ signaling patterns.
- The interplay between these messengers and release mechanisms allows for diverse cellular responses.
- Cells utilize distinct combinations of messengers to produce unique Ca2+ signaling signatures based on stimuli.
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