AUTHOR=Rahman Nawreen , Buck Jochen , Levin Lonny R.

TITLE=pH sensing via bicarbonate-regulated “soluble” adenylyl cyclase (sAC)

JOURNAL=Frontiers in Physiology

VOLUME=4

YEAR=2013

URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2013.00343

DOI=10.3389/fphys.2013.00343

ISSN=1664-042X

ABSTRACT=<p>Soluble adenylyl cyclase (sAC) is a source of the second messenger cyclic adenosine 3′, 5′ monophosphate (cAMP). sAC is directly regulated by bicarbonate (HCO<sup>−</sup><sub>3</sub>) ions. In living cells, HCO<sup>−</sup><sub>3</sub> ions are in nearly instantaneous equilibrium with carbon dioxide (CO<sub>2</sub>) and pH due to the ubiquitous presence of carbonic anhydrases. Numerous biological processes are regulated by CO<sub>2</sub>, HCO<sup>−</sup><sub>3</sub>, and/or pH, and in a number of these, sAC has been shown to function as a physiological CO<sub>2</sub>/HCO<sub>3</sub>/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.</p>