Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:4.6.1.1 (adenylate cyclase)
 19,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The intracellular distribution of measles virus inclusion bodies in persistently infected human cells (AV3A1/MV) changed markedly following continuous exposure to 3', 5' cyclic adenosine monophosphate (cAMP). When assayed by immunofluorescence, the number of cells with intranuclear virus inclusions increased from 5 to 10% to 80 to 90% after exposure to 1 mM-cAMP for 4 days. Exposure of cells to cAMP also resulted in a twofold increase in the average number of inclusions in invaded nuclei. Similar but less pronounced changes occurred in cells treated with inducers of adenylate cyclase and an inhibitor of phosphodiesterase. Examination of cAMP-treated cells by electron microscopy indicated that viral inclusion bodies consisted of typical helical nucleocapsids. No evidence of nucleocapsids crossing the nuclear membrane (through nuclear pores) was found.
J Gen Virol 1985 Sep
PMID:Enhanced intranuclear expression of measles virus following exposure of persistently infected cells to cyclic AMP. 299 91

Forskolin, an activator of adenylate cyclase, depressed spontaneous locomotor activity when injected intracerebroventricularly into mice in doses of 10 and 100 micrograms. The findings suggest that increases in brain cAMP levels may be associated with a reduction in excitability.
Gen Pharmacol 1985
PMID:Depressant effect of forskolin on spontaneous locomotor activity in mice. 299 73

We investigated the relationship in Saccharomyces cerevisiae between the cell cycle start function, CDC25, and two mutants defining components of the cAMP pathway. The thermolabile adenylate cyclase mutant cyr1-2(ts) is phenotypically similar to the temperature-sensitive mutant cdc25(ts) in that both mutants, when shifted to the restrictive temperature, arrest in G1 of the cell cycle and permit the initiation of meiosis and sporulation. The mutant bcy1 [a lesion resulting in a low level of regulatory (R) subunit and a high level of active, catalytic (C) subunit of the cAMP-dependent protein kinase] suppresses the temperature-sensitive phenotype of cyr1-2(ts) and confers an asporogenous phenotype. We found that cdc25(ts) complemented cyr1-2(ts), and, unlike cyr1-2(ts), was not suppressible by bcy1, demonstrating that CYR1 and CDC25 must encode different functions. Also our results indicate that CDC25 does not encode the R subunit of the cAMP-dependent protein kinase. In addition, although the cdc25(ts)bcy1 double mutant was temperature sensitive like cdc25(ts), we found that the cdc25(ts)bcy1 homozygous diploid was asporogenous like bcy1/bcy1. The inability of the cdc25(ts)bcy1 double mutant to sporulate demonstrated that CDC25 does not encode the C subunit of the cAMP kinase, and indicated that the CDC25 function modulates the cAMP pathway to control meiosis and sporulation. Further, the temperature-sensitive phenotype of the double mutant, and hence the inability of bcy1 to suppress cdc25(ts), suggested that a second CDC25 cell cycle function exists which is independent of the cAMP pathway.(ABSTRACT TRUNCATED AT 250 WORDS)
J Gen Microbiol 1986 May
PMID:Control of the cAMP pathway by the cell cycle start function, CDC25, in Saccharomyces cerevisiae. 302 94

The role of cyclic AMP (cAMP) as mediator of ACTH action on interrenal steroidogenesis was evaluated in juvenile coho salmon (Oncorhynchus kisutch). Head kidneys (containing the interrenal cells) were incubated in the absence or presence of putative adenylate cyclase activators (forskolin and cholera toxin), ACTH combined with putative adenylate cyclase inhibitors (hydrolysis-resistant ATP analogs), dibutyryl cyclic (dbc) AMP, dbcGMP, or phosphatidylinositol. The cortisol content of the incubation medium was subsequently determined by radioimmunoassay. Forskolin markedly stimulated cortisol secretion by interrenal cells. Adenylate cyclase inhibitors depressed the steroidogenic response to ACTH. Dibutyryl cAMP, but not dbcGMP, enhanced steroid secretion. Thus, cAMP seems to be an important "second messenger" for ACTH action on salmon interrenal cells. In contrast to findings in mammalian adrenocortical cells, exogenous phosphatidylinositol and cholera toxin failed to stimulate corticosteroid secretion in salmon interrenal cells. However, it was unclear whether these negative findings were an artifact resulting from the use of kidney tissue fragments instead of isolated interrenal cells.
Gen Comp Endocrinol 1986 Aug
PMID:Adenylate cyclase activators and inhibitors, cyclic nucleotide analogs, and phosphatidylinositol: effects on interrenal function of coho salmon (Oncorhynchus kisutch) in vitro. 302 80

In Escherichia coli K12 expression of the adenylate cyclase gene is subject to multiple controls. In order to gain understanding of the regulation of adenylate cyclase synthesis, operon and protein fusions were constructed by in vitro recombination either into bacteriophage lambda or low-copy-number plasmids, or directly on the chromosome at the cya locus. The fusions were used in physiological experiments as probes to study transcriptional and translational controls of cya expression. It was found that adenylate cyclase synthesis was insensitive to glucose effects. As already described by other workers, the CAP-cAMP complex had a moderate negative control on cya expression. In addition it was observed that concomitant with a severe slackening of growth rate, specific to the growth of cya strains in rich medium, cya expression was considerably enhanced. This increase of adenylate cyclase synthesis did not appear to be directly dependent on the presence of a functional cAMP receptor (CAP), and seemed to be controlled at the level of transcription. Finally, translation of the cya message was very weak when compared to cya transcription (the mRNA level was the same in protein and operon fusions.
J Gen Microbiol 1988 Feb
PMID:Aspects of the regulation of adenylate cyclase synthesis in Escherichia coli K12. 304 35

Various truncated CYR1 genes of Saccharomyces cerevisiae were fused to efficient promoters and expressed in Escherichia coli and S. cerevisiae cells with or without the RAS genes. The catalytic domain of adenylate cyclase encoded by the 3'-terminal 1.3 kb region of the open reading frame of the CYR1 gene produced cyclic AMP, irrespective of the presence of RAS genes. The product of the 3'-terminal 2.1 kb region of CYR1 showed guanine nucleotide-dependent adenylate cyclase activity and produced a large amount of cAMP in the presence of the RAS gene. Thus, the domain encoded by the 0.8 kb region adjacent to the catalytic domain is associated with the regulatory function of the RAS products. The cyr1 RAS1 RAS2 cells carrying the 3'-terminal 1.3 kb region of CYR1 were unable to respond to environmental signals such as sulfur starvation and temperature shift, but the cyr1 cells carrying the 2.1 kb region and at least one RAS gene were able to respond to these signals. The environmental signals may be transferred to the adenylate cyclase system through the RAS products.
Mol Gen Genet 1987 Dec
PMID:Identification of the domain of Saccharomyces cerevisiae adenylate cyclase associated with the regulatory function of RAS products. 332 73

Several strains of Escherichia coli K12 were compared for activity of the periplasmic "pH 2.5 acid phosphatase", an enzyme whose expression is regulated negatively by cyclic AMP. Two distinct enzyme levels differing by about four-fold were observed. This strain-dependent difference does not involve modifications in the structure of the enzyme, but results from a difference in its expression. We show that strains with a high- or a low level of enzyme differ in the gene locus appR located in the 59 min region of the chromosome, a site remote from the structural gene appA; the appR+ versus appR enzyme ratio is 3-4 in wild-type strains, adenylate cyclase-deficient strains (cya) or cyclic AMP receptor protein-deficient strains (crp) grown in rich medium or in glucose minimal medium, but is close to 1 in cya strains in the presence of 0.1 mM cyclic AMP and in wild-type strains grown with succinate as carbon source; in a crp genetic background, appR strains, contrary to appR+ strains, are able to grow on minimal medium with succinate as the sole carbon source. The selection, from an appR+ crp strain, of clones growing on succinate-minimal medium, yielded mutations in the same region of the chromosome and showing the same phenotype as "naturally-occurring" appR strains. All appR strains analysed so far showed other similar deficiencies. The possibility that mutated appR gene products might function as weak substitutes for a functional cAMP-CRP complex is discussed.
Mol Gen Genet 1986 Feb
PMID:Pleiotropic mutations in appR reduce pH 2.5 acid phosphatase expression and restore succinate utilisation in CRP-deficient strains of Escherichia coli. 351 93

Melanophore-stimulating hormone (MSH) release from the pars intermedia of the pituitary gland is probably regulated by multiple factors of hypothalamic origin. We have examined a number of potential regulatory factors for their effects on MSH release from the amphibian Xenopus laevis. Serotonin and acetylcholine have no effect on MSH release. Both adrenaline and noradrenaline inhibit release of MSH in a dose-dependent manner. Studies with specific receptor agonists and antagonists reveal that these neurotransmitters exert their in vitro effects primarily through a dopamine D-2 receptor, although an alpha-adrenergic receptor could not be excluded. We further conclude that the pars intermedia of X. laevis lacks a beta-adrenergic receptor for the regulation of MSH secretion from the pars intermedia. In mammals, this receptor activates the adenylate cyclase system. Our studies reveal that despite the lack of beta-adrenergic receptors, cyclic-AMP is likely an intracellular factor involved in the stimulation of MSH release.
Gen Comp Endocrinol 1986 Sep
PMID:Regulation of melanotropin release from the pars intermedia of the amphibian Xenopus laevis: evaluation of the involvement of serotonergic, cholinergic, or adrenergic receptor mechanisms. 355 70

Basal and stimulated adenylate cyclase specific activity was characterized in gill plasma membrane of freshwater-adapted trout by measuring the conversion of [alpha-32P]ATP into [alpha-32P]cyclic AMP. Both basal and isoproterenol- or sodium fluoride-stimulated enzyme activities were linear with time and protein concentration. The optimum activities were obtained using a pH buffer of 7.5 and a temperature of 20 degrees. The Km for ATP was 0.5 mM in the presence or absence of the stimulators. The presence of 10(-5) M guanosine-5'-triphosphate and 4 X 10(-3) M MgCl2 (2.41 X 10(-3) M free Mg2+) was required to optimize not only the basal activity but also the stimulation ratio (test/control) produced by these agents. On the contrary, Ca2+ was inhibitory. IC50 for CaCl2 was 5 X 10(-4) M (10(-7) M free Ca2+) in the presence or absence of the stimulators. Under these conditions, the basal adenylate cyclase specific activity was 400-450 pmol/mg protein/10 min. A maximal stimulation was produced by isoproterenol or PGE1 10(-5) M (50% increase over basal activity) or by glucagon 5.7 X 10(-10) M (30%). In addition, this enzyme displayed high sensitivity to sodium fluoride which induced a particularly large maximal effect (370%) at a concentration of 10(-2) M.
Gen Comp Endocrinol 1987 Aug
PMID:Basal and stimulated adenylate cyclase activity in the gill epithelium of the rainbow trout. 362 74

Human serum enhanced the PGE1 stimulated adenyl cyclase activity in membrane rich fraction of rat calvaria, but heated serum did not. Human C6 enhanced the PGE1 stimulated adenyl cyclase activity. C6 did not enhance the PTH stimulated adenyl cyclase activity. The enhancement of the PGE1 stimulated adenyl cyclase activity with C6 was due to increasing Vmax. The enhancement of the enzyme activity with C6 was significantly inhibited with anti-C6 antibody. Adenyl cyclase was not activated with C6 alone.
Gen Pharmacol 1986
PMID:Effect of sixth component of complement on the prostaglandin E1 stimulated adenyl cyclase activity in rat calvaria. 378 Dec 5


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>