Adenylate Cyclase III/ADCY3

Adenylate cyclases are enzymes which interact with and are activated by the GTP bound alpha subunits of trimeric G-proteins. Activated adenylate cyclases are responsible for the production of the important "second messenger" signalling molecule cyclic-AMP, which is generated from ATP. The type III adenylate cyclase enzyme is localized in the membranes surrounding the cilia in neurons.

Adenylate cyclase type III is a large complex molecule of, in the human, 1145 amino acids with a deduced molecular weight of 129kDa. The protein may be variably glycosylated, so that on SDS-PAGE and western blots it runs as a diffuse band of about 160kDa in cortex and about 200kDa in olfactory epithelium. The molecule has a complex structure, with 12 transmembrane domains and two cyclase domains. Each cyclase domain is immediately C-terminal to 6 transmembrane segments, but only the second, C-terminal cyclase is believed to be catalytically active.