In:
Proceedings of the National Academy of Sciences, Proceedings of the National Academy of Sciences, Vol. 98, No. 26 ( 2001-12-18), p. 14859-14864
Abstract:
Sponges (phylum Porifera) are the phylogenetically oldest
metazoan animals, their evolution dating back to 600 million years ago. Here we demonstrate that sponges express ADP-ribosyl cyclase activity,
which converts NAD + into cyclic ADP-ribose, a potent and
universal intracellular Ca 2+ mobilizer. In Axinella polypoides (Demospongiae, Axinellidae),
ADP-ribosyl cyclase was activated by temperature increases by means of an abscisic acid-induced, protein kinase A-dependent mechanism. The
thermosensor triggering this signaling cascade was a heat-activated cation channel. Elucidation of the complete thermosensing pathway in
sponges highlights a number of features conserved in higher organisms: ( i ) the cation channel thermoreceptor, sensitive to
heat, mechanical stress, phosphorylation, and anesthetics, shares all of the functional characteristics of the mammalian heat-activated
background K + channel responsible for central and
peripheral thermosensing; ( ii ) involvement of the
phytohormone abscisic acid and cyclic ADP-ribose as its second messenger is reminiscent of the drought stress signaling pathway in
plants. These results suggest an ancient evolutionary origin of this stress-signaling cascade in a common precursor of modern Metazoa and
Metaphyta.
Type of Medium:
Online Resource
ISSN:
0027-8424
,
1091-6490
DOI:
10.1073/pnas.261448698
Language:
English
Publisher:
Proceedings of the National Academy of Sciences
Publication Date:
2001
detail.hit.zdb_id:
209104-5
detail.hit.zdb_id:
1461794-8
SSG:
11
SSG:
12
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