ECB-ART-47880
Cell
2002 Nov 27;1115:703-8. doi: 10.1016/s0092-8674(02)01082-6.
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NAADP mobilizes Ca(2+) from reserve granules, lysosome-related organelles, in sea urchin eggs.
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.
PubMed ID: 12464181
Article link: Cell
Genes referenced: LOC100887844 LOC576539