Adenylate cyclase (AC) enzyme uses ATP as its substrate to produce Cyclic AMP (cAMP), a ubiquitous signalling molecule that mediates many cellular processes by activating cAMP- dependent kinases and also inducing protein-protein interactions. Mammalian adenylate cyclase has nine closely related membrane-bound isoforms (AC1-9) showing significant sequence homology and sharing the same overall structure: two hydrophobic transmembrane domains, and two cytoplasmic domains that are responsible for the catalytic activity. These isoforms differ in both their tissue specificity and their regulation [1,2]. This entry represents a region of unknown function found in many of these isoforms. It is part of the N-terminal cytoplasmic domain but its presence is not necessary for catalytic activity [3].

1: Regulation and role of adenylyl cyclase isoforms. Hanoune J, Defer N; Annu Rev Pharmacol Toxicol. 2001;41:145-174. PMID:11264454

2: Regulation and organization of adenylyl cyclases and cAMP. Cooper DM; Biochem J. 2003;375:517-529. PMID:12940771

3: Crystal structure of the catalytic domains of adenylyl cyclase in a complex with Gsalpha.GTPgammaS. Tesmer JJ, Sunahara RK, Gilman AG, Sprang SR; Science. 1997;278:1907-1916. PMID:9417641