pH sensing via bicarbonate-regulated “soluble” adenylyl cyclase (sAC)
نویسندگان
چکیده
Soluble adenylyl cyclase (sAC) is a source of the second messenger cyclic adenosine 3', 5' monophosphate (cAMP). sAC is directly regulated by bicarbonate (HCO(-) 3) ions. In living cells, HCO(-) 3 ions are in nearly instantaneous equilibrium with carbon dioxide (CO2) and pH due to the ubiquitous presence of carbonic anhydrases. Numerous biological processes are regulated by CO2, HCO(-) 3, and/or pH, and in a number of these, sAC has been shown to function as a physiological CO2/HCO3/pH sensor. In this review, we detail the known pH sensing functions of sAC, and we discuss two highly-studied, pH-dependent pathways in which sAC might play a role.
منابع مشابه
Role of the bicarbonate-responsive soluble adenylyl cyclase in pH sensing and metabolic regulation
The evolutionarily conserved soluble adenylyl cyclase (sAC, adcy10) was recently identified as a unique source of cAMP in the cytoplasm and the nucleus. Its activity is regulated by bicarbonate and fine-tuned by calcium. As such, and in conjunction with carbonic anhydrase (CA), sAC constitutes an HCO(-) 3/CO(-) 2/pH sensor. In both alpha-intercalated cells of the collecting duct and the clear c...
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Carbon dioxide (CO(2)) is produced by living organisms as a byproduct of metabolism. In physiological systems, CO(2) is unequivocally linked with bicarbonate (HCO(3)(-)) and pH via a ubiquitous family of carbonic anhydrases, and numerous biological processes are dependent upon a mechanism for sensing the level of CO(2), HCO(3), and/or pH. The discovery that soluble adenylyl cyclase (sAC) is dir...
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Soluble adenylyl cyclase (sAC) represents a novel form of mammalian adenylyl cyclase structurally, molecularly, and biochemically distinct from the G protein-regulated, transmembrane adenylyl cyclases (tmACs). sAC possesses no transmembrane domains and is insensitive to classic modulators of tmACs, such as heterotrimeric G proteins and P site ligands. Thus, sAC defines an independently regulate...
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