To investigate the effects of deep-sea temperatures and hydrostatic pressures on transmembrane signal transduction, the Ax adenosine receptor/inhibitory G protein/adenylyl cyclase complex was studied in brain membranes from two congeneric marine fishes that live at different depths. These scorpaenid species, Sebastolobus alascanus and S. altivelis, have been used as a model system to study adap...

Adenylyl cyclases are a nine-member family of differentially regulated enzymes responsible for the synthesis of cAMP. cAMP is an important second messenger that contributes to the regulation of airway smooth muscle tone. However, little is known regarding the expression and regulation of adenylyl cyclase isoforms in airway smooth muscle cells. Nondegenerate specific primers were designed for al...

Cholera toxin alters intestinal function by stimulation of adenylyl cyclase [ATP pyrophosphate-lyase (cyclizing) or adenylate cyclase, EC 4.6.1.1]. The mechanism of this activation is unknown and particularly puzzling because adenylyl cyclase is confined to the basal lateral membrane of enterocytes, whereas it is the brush border membrane that binds the toxin and contains proteins that undergo ...

PAM (Protein Associated with Myc) is an almost ubiquitously expressed protein that is one of the most potent inhibitors of adenylyl cyclase activity known so far. Here we show that PAM is localized at the endoplasmic reticulum in HeLa cells and that upon serum treatment PAM is recruited to the plasma membrane, causing an inhibition of adenylyl cyclase activity. We purified the serum factor that...

cAMP is a key player in the intracellular signaling pathways of hormones, neurotransmitters, odorants, and chemokines. By activating PKA and cyclic nucleotide-gated ion channels, this protean second messenger can change cellular attributes as diverse as the membrane potential and the rate of cell division. The key step in regulating intracellular cAMP is modulation of adenylyl cyclase activity....

Cyclase-associated protein (CAP) is an evolutionarily conserved regulator of the G-actin/F-actin ratio and, in yeast, is involved in regulating the adenylyl cyclase activity. We show that cell polarization, F-actin organization, and phototaxis are altered in a Dictyostelium CAP knockout mutant. Furthermore, in complementation assays we determined the roles of the individual domains in signaling...

OBJECTIVE It has been assumed that some behavioral changes associated with repeated exposure to dopaminergic psychostimulant drugs might be explained by changes in activity of dopamine receptors, including the dopamine D(1) receptor, which is linked by a stimulatory G protein to the effector enzyme adenylyl cyclase. To establish whether dopamine D(1) receptor function might be altered in human ...

The adenylyl cyclase gene, cyr1, of Schizosaccharomyces pombe has been cloned. We have begun an analysis of the function and regulation of adenylyl cyclase by disrupting this gene and by over-expressing all or parts of this gene in various strains. cyr1- strains are viable and contain no measurable cyclic AMP. They conjugate and sporulate under conditions that normally inhibit wild-type strains...

OBJECTIVE cAMP is a critical regulator of metabolic and cardiovascular function. However, the role of genetic variability in the regulation of cAMP-mediated effects is unclear. Therefore, we assessed the effect of the expression of a recently identified missense genetic variant of adenylyl cyclase isoform 6 (ADCY6 S674). METHODS AND RESULTS In rat vascular smooth muscle cells, gene transfer o...

Whereas mobilization of intracellular Ca 2 1 stimulates neuronal adenylyl cyclase via Ca 2 1 /calmodulin, mobilized Ca 2 1 directly inhibits adenylyl cyclase in other tissues. To determine the physiologic role of the Ca 2 1 -dependent interaction between Na 1 /Ca 2 1 exchange and b -adrenergic signal transduction in the intact heart, digoxin (0.3 mg/kg) was administered intravenously in rabbits...