Format

Send to

Choose Destination
Cell. 2002 Nov 27;111(5):703-8.

NAADP mobilizes Ca(2+) from reserve granules, lysosome-related organelles, in sea urchin eggs.

Author information

1
Department of Pharmacology, University of Oxford, Mansfield Road, OX1 3QT, Oxford, United Kingdom. grant.churchill@pharm.ox.ac.uk

Abstract

Nicotinic acid adenine dinucleotide phosphate (NAADP) mobilizes Ca(2+) in many cells and species. Unlike other Ca(2+)-mobilizing messengers, NAADP mobilizes Ca(2+) from an unknown store that is not the endoplasmic reticulum, the store traditionally associated with messenger-mediated Ca(2+) signaling. Here, we demonstrate the presence of a Ca(2+) store in sea urchin eggs mobilized by NAADP that is dependent on a proton gradient maintained by an ATP-dependent vacuolar-type proton pump. Moreover, we provide pharmacological and biochemical evidence that this Ca(2+) store is the reserve granule, the functional equivalent of a lysosome in the sea urchin egg. These findings represent an unsuspected mechanism for messenger-mediated Ca(2+) release from lysosome-related organelles.

PMID:
12464181
DOI:
10.1016/s0092-8674(02)01082-6
[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center