Adenylate cyclase and cyclic AMP phosphodiesterase activity during the mitotic cycle of Physarum polycephalum

1978 ◽  
Vol 85 (2) ◽  
pp. 579-584 ◽  
Author(s):  
James R. Lovely ◽  
Richard J. Threlfall
Keyword(s):  
Cyclic Amp ◽  
Adenylate Cyclase ◽  
Physarum Polycephalum ◽  
Mitotic Cycle ◽  
Phosphodiesterase Activity ◽  
Cyclic Amp Phosphodiesterase

scholarly journals Ontogenetic changes in adenylate cyclase, cyclic AMP phosphodiesterase and calmodulin in chick ventricular myocardium

1987 ◽  
Vol 243 (2) ◽  
pp. 525-531 ◽  
Author(s):  
P M Epstein ◽  
D M Andrenyak ◽  
C J Smith ◽  
A J Pappano
Keyword(s):  
Cyclic Amp ◽  
Embryonic Development ◽  
Adenylate Cyclase ◽  
Cyclic Nucleotide ◽  
Sodium Acetate ◽  
Specific Activity ◽  
Ventricular Myocardium ◽  
Phosphodiesterase Activity ◽  
Ontogenetic Changes ◽  
Cyclic Amp Phosphodiesterase

The activities of cyclic AMP phosphodiesterase (3′,5′-cyclic nucleotide 5′-nucleotidohydrolase, EC 3.1.4.17) and adenylate cyclase [ATP pyrophosphate-lyase (cyclizing), EC 4.6.1.1] and calmodulin content during development of chick ventricular myocardium were determined. The specific activity of cyclic AMP phosphodiesterase was relatively low in early embryos, increased during embryogenesis by about 4-fold to reach highest values just before hatching, and then decreased by approx. 30% within 1 week after hatching. In contrast, adenylate cyclase did not change during embryonic development, but increased by approx. 50% within 1 week after hatching. Calmodulin content remained constant at 9 micrograms/g wet wt. during embryonic development and decreased to 6 micrograms/g wet wt. by 1 week after hatching. DEAE-Sephacel chromatography of chick ventricular supernatant revealed a single major form of cyclic nucleotide phosphodiesterase activity in early embryonic (9-day E) and hatched (6-day H) chicks. This enzyme form was eluted at approx. 0.27 M-sodium acetate, hydrolysed both cyclic AMP and cyclic GMP, and was sensitive to stimulation by Ca2+-calmodulin, with an apparent Km for calmodulin of approx. 1 nM. In contrast, ventricular supernatant from late-embryonic (18-day E) chicks contained two forms of phosphodiesterase separable on DEAE-Sephacel: the same form as that seen at other ages, plus a cyclic AMP-specific form which was eluted at approx. 0.65 M-sodium acetate and was insensitive to stimulation by Ca2+-calmodulin. The ontogenetic changes in cyclic AMP phosphodiesterase activity in chick ventricular myocardium are consistent with reported ontogenetic changes in the steady-state contents of cyclic AMP in this tissue and suggest that this enzyme may be responsible for the changes that occur in this nucleotide during development of chick myocardium.

Cyclic AMP phosphodiesterase activity in mouse pancreatic islets Effects of calmodulin and phospholipids

1986 ◽  
Vol 111 (4) ◽  
pp. 533-538 ◽  
Author(s):  
Kirsten Capito ◽  
Carl Jørgen Hedeskov ◽  
Peter Thams
Keyword(s):  
Enzyme Activity ◽  
Cyclic Amp ◽  
Adenylate Cyclase ◽  
Pancreatic Islets ◽  
Total Activity ◽  
Particulate Fraction ◽  
Supernatant Fraction ◽  
Phosphodiesterase Activity ◽  
Cyclic Amp Phosphodiesterase ◽  
Mouse Pancreatic Islets

Abstract. The activity of cyclic AMP phosphodiesterase in mouse pancreatic islets was investigated. 85% of the total activity was found in a 27 000 g supernatant fraction. The phosphodiesterase activity in the supernatant fraction, but not in the particulate fraction, was stimulated approximately 20% by Ca2+ (10−5m) and calmodulin (1 μm). The Km (cyclic AMP) of the unstimulated enzyme in the supernatant fraction was 20 μm, and the Vmax was 2 nmol/min × mg protein−1. The possible influence of a range of phospholipids was investigated. PI* and PS (150 μg/ml) inhibited the enzyme 20–30% both in the absence and presence of Ca2+/calmodulin, whereas PE, PC and PA did not affect the enzyme activity. ATP (1 mm) did not affect the particulate or supernatant fraction phosphodiesterase either in the absence or presence of Ca2+/calmodulin or Ca2+/phospholipid. It is concluded that, contrary to islet adenylate cyclase, islet cyclic AMP phosphodiesterase may be regulated by Ca2+/calmodulin.

scholarly journals Regulation by forskolin of cyclic AMP phosphodiesterase and protein kinase C activity in LLC-PK1 cells

1991 ◽  
Vol 279 (1) ◽  
pp. 23-27 ◽  
Author(s):  
R J Anderson ◽  
R Breckon ◽  
D Colston
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Cyclic Amp ◽  
Adenylate Cyclase ◽  
Phosphodiesterase Activity ◽  
Cyclic Amp Phosphodiesterase ◽  
Kinase C ◽  
Naturally Occurring ◽  
Protein Kinase C Activity ◽  
Structural Identity

Forskolin, a naturally occurring activator of adenylate cyclase, inhibits total and high-affinity cyclic AMP phosphodiesterase activity in soluble and particulate fractions of cultured LLC-PK1 renal epithelial cells. The naturally occurring forskolin analogue 1,9-dideoxyforskolin, which does not stimulate adenylate cyclase activity, is a more potent inhibitor of cyclic AMP phosphodiesterase activity than forskolin. To clarify the structural feature of the forskolin molecule responsible for inhibition of cyclic AMP phosphodiesterase activity, the effects of two agents which share structural identity with portions of the forskolin ring were tested. The steroid 5-pregnenolone, but not the hexose alpha-D-galactose, inhibited cyclic AMP phosphodiesterase activity in LLC-PK1 cells. Forskolin and 1,9-dideoxyforskolin both stimulate protein kinase C activity in LLC-PK1 cells. The effect of 1,9-dideoxyforskolin in stimulating LLC-PK1 protein kinase C activity can be attenuated by staurosporine. Both 5-pregnenolone and alpha-D-galactose also stimulate protein kinase C activity in LLC-PK1 cells. 5-Pregnenolone and the phorbol ester phorbol 12-myristate 13-acetate cause translocation of protein kinase C from a soluble to a particulate fraction, while both 1,9-dideoxyforskolin and alpha-D-galactose increase protein kinase C activity in both soluble and particulate fractions. Our results demonstrate that forskolin exerts diverse enzymic effects in cultured LLC-PK1 cells.

Cloning and characterization of the low-affinity cyclic AMP phosphodiesterase gene of Saccharomyces cerevisiae

1987 ◽  
Vol 7 (10) ◽  
pp. 3629-3636
Author(s):  
J Nikawa ◽  
P Sass ◽  
M Wigler
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cyclic Amp ◽  
Copy Number ◽  
Growth Arrest ◽  
Yeast Cells ◽  
Phosphodiesterase Activity ◽  
Camp Phosphodiesterase ◽  
High Affinity ◽  
Cyclic Amp Phosphodiesterase

Saccharomyces cerevisiae contains two genes which encode cyclic AMP (cAMP) phosphodiesterase. We previously isolated and characterized PDE2, which encodes a high-affinity cAMP phosphodiesterase. We have now isolated the PDE1 gene of S. cerevisiae, which encodes a low-affinity cAMP phosphodiesterase. These two genes represent highly divergent branches in the evolution of phosphodiesterases. High-copy-number plasmids containing either PDE1 or PDE2 can reverse the growth arrest defects of yeast cells carrying the RAS2(Val-19) mutation. PDE1 and PDE2 appear to account for the aggregate cAMP phosphodiesterase activity of S. cerevisiae. Disruption of both PDE genes results in a phenotype which resembles that induced by the RAS2(Val-19) mutation. pde1- pde2- ras1- ras2- cells are viable.

scholarly journals In VitroEffect of Inhibin on Cyclic AMP-Phosphodiesterase Activity in Rat Testes

1982 ◽  
Vol 3 (1) ◽  
pp. 69-71
Author(s):  
ANIL R. SHETH ◽  
S. VIJAYALAKSHMI ◽  
PARUL R. SHETH ◽  
A. H. BANDIVDEKAR ◽  
SUDHIR B. MOODBIDRI
Keyword(s):  
Cyclic Amp ◽  
Phosphodiesterase Activity ◽  
Cyclic Amp Phosphodiesterase

scholarly journals Specific antibodies and the selective inhibitor ICI 118233 demonstrate that the hormonally stimulated ‘dense-vesicle’ and peripheral-plasma-membrane cyclic AMP phosphodiesterases display distinct tissue distributions in the rat

1987 ◽  
Vol 248 (3) ◽  
pp. 897-901 ◽  
Author(s):  
N J Pyne ◽  
N Anderson ◽  
B E Lavan ◽  
G Milligan ◽  
H G Nimmo ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Plasma Membrane ◽  
Cyclic Amp ◽  
Rat Liver ◽  
White Adipose Tissue ◽  
Tissue Homogenate ◽  
Phosphodiesterase Activity ◽  
Cyclic Amp Phosphodiesterase ◽  
Peripheral Plasma ◽  
Membrane Enzyme

Polyclonal-antibody preparations DV1 and PM1, raised against purified preparations of rat liver insulin-stimulated ‘dense-vesicle’ and peripheral-plasma-membrane cyclic AMP phosphodiesterases, were used to analyse rat liver homogenates by Western-blotting techniques. The antibody DV1 identified only the 63 kDa native subunit of the ‘dense-vesicle’ enzyme, and the antibody PM1 only the 52 kDa subunit of the plasma-membrane enzyme. These antibodies also detected the subunits of these two enzymes in homogenates of kidney, heart and white adipose tissue from rat. Quantitative immunoblotting demonstrated that the amount of these enzymes (by wt.) varied in these different tissues, as did the expression of these two enzymes, relative to each other, by a factor of as much as 7-fold. The ratio of the dense-vesicle enzyme to the peripheral-plasma-membrane enzyme was lowest in liver and kidney and highest in heart and white adipose tissue. ICI 118233 was shown to inhibit selectively the ‘dense-vesicle’ cyclic AMP phosphodiesterase in liver. It did this in a competitive fashion, with a Ki value of 3.5 microM. Inhibition of tissue-homogenate cyclic AMP phosphodiesterase activity by ICI 118233 was used as an index of the contribution to activity by the ‘dense-vesicle’ enzyme. By this method, a tissue distribution of the ‘dense-vesicle’ enzyme was obtained which was similar to that found by using the immunoblotting technique. The differential expression of isoenzymes of cyclic AMP phosphodiesterase activity in various tissues might reflect a functional adaptation, and may provide the basis for the different physiological actions of compounds which act as selective inhibitors.

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