title: High adenylyl cyclase activity and in vivo cAMP fluctuations in corals suggest central physiological role.
abstract: Corals are an ecologically and evolutionarily significant group, providing the framework for coral reef biodiversity while representing one of the most basal of metazoan phyla. However, little is known about fundamental signaling pathways in corals. Here we investigate the dynamics of cAMP, a conserved signaling molecule that can regulate virtually every physiological process. Bioinformatics revealed corals have both transmembrane and soluble adenylyl cyclases (AC). Endogenous cAMP levels in live corals followed a potential diel cycle, as they were higher during the day compared to the middle of the night. Coral homogenates exhibited some of the highest cAMP production rates ever to be recorded in any organism; this activity was inhibited by calcium ions and stimulated by bicarbonate. In contrast, zooxanthellae or mucus had >1000-fold lower AC activity. These results suggest that cAMP is an important regulator of coral physiology, especially in response to light, acid/base disturbances and inorganic carbon levels.
authors: Scripps Institution of Oceanography, Marine Biology Research Division, La Jolla, California, United States of America.
authors: K L
authors: KL
authors: Barott
authors: Y
authors: Y
authors: Helman
authors: L
authors: L
authors: Haramaty
authors: M E
authors: ME
authors: Barron
authors: K C
authors: KC
authors: Hess
authors: J
authors: J
authors: Buck
authors: L R
authors: LR
authors: Levin
authors: M
authors: M
authors: Tresguerres
mesh_terms: D000262:Adenylyl Cyclases / Q000378:metabolism*; D000818:Animals; D037421:Anthozoa / Q000187:drug effects / Q000201:enzymology* / Q000502:physiology*; D001639:Bicarbonates / Q000494:pharmacology; D002940:Circadian Rhythm / Q000187:drug effects; D000242:Cyclic AMP / Q000096:biosynthesis / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D010802:Phylogeny; D017386:Sequence Homology, Amino Acid
chemical_list: D001639:Bicarbonates; D000242:Cyclic AMP; D000262:Adenylyl Cyclases