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© 2001 by The American Society for Biochemistry and Molecular Biology, Inc.
Prolonged Inactivation of Nicotinic Acid Adenine Dinucleotide Phosphate-induced Ca2+ Release Mediates a Spatiotemporal Ca2+ Memory* and
From the Department of Pharmacology, University of Oxford, Oxford
OX1 3QT, United Kingdom
Although numerous extracellular stimuli
are coupled to increases in intracellular Ca2+,
different stimuli are thought to achieve specificity by eliciting different spatiotemporal Ca2+ increases. We investigated
the effect of nicotinic acid adenine dinucleotide phosphate (NAADP)
inactivation on spatiotemporal Ca2+ signals in intact sea
urchin eggs. The photorelease of NAADP but not inositol
1,4,5-trisphosphate or cyclic ADP-ribose resulted in
self-inactivation. When NAADP was released first locally and subsequently globally, the spatial pattern of the first response shaped
that of the second. Specifically, the local release of NAADP created a
Ca2+ gradient that was reversed during the subsequent
global release of NAADP. Neither cyclic ADP-ribose nor inositol
1,4,5-trisphosphate showed a similar effect. In contrast to
homogenates, NAADP inactivation was reversible in intact eggs with
resensitization occurring in ~20 min. Because initial NAADP responses
affect later responses, NAADP can serve as a mechanism for a
Ca2+ memory that has both spatial and temporal components.
This NAADP-mediated Ca2+ memory provides a novel mechanism
for cells to control spatiotemporal Ca2+ increases.
* This work was supported by the Wellcome Trust.The costs of publication of this article were defrayed in part by the payment of page charges. The article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
To whom correspondence should be addressed: Dept. of Pharmacology,
University of Oxford, Mansfield Road, Oxford OX1 3QT, United Kingdom.
Tel.: 01865-271-606; Fax: 01865-271-853; E-mail: grant. churchill@pharm.ox.ac.uk.
Copyright © 2001 by The American Society for Biochemistry and Molecular Biology, Inc. THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
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Science Signaling. ISSN 1937-9145 (online), 1945-0877 (print). Pre-2008: Science's STKE. ISSN 1525-8882