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. 1972 Feb;69(2):459–462. doi: 10.1073/pnas.69.2.459

Regulation of Adenosine 3′:5′-Cyclic Monophosphate Phosphodiesterase Activity in Fibroblasts by Intracellular Concentrations of Cyclic Adenosine Monophosphate

Massimo D'Armiento 1, George S Johnson 1, Ira Pastan 1
PMCID: PMC426480  PMID: 4333987

Abstract

Cyclic AMP-phosphodiesterase is present in various mouse fibroblasts. Contact-inhibited 3T3 cells contain two forms of the enzyme, one with a Km of 2.5 μM and the second with a Km of 71 μM. As 3T3 cells grow to confluency and cAMP concentrations rise, the activity of the first enzyme increases, whereas that of the second is unchanged. A line of SV40-transformed 3T3 cells with low cAMP concentration also has low levels of the cAMP-phosphodiesterase with a Km of 2.5 μM. Treatment of 3T3 and SV40-transformed 3T3 cells with dibutyryl cAMP and theophylline increases cAMP-phosphodiesterase accumulation. This accumulation is blocked by cycloheximide and actinomycin D. The newly formed enzyme resembles the higher affinity enzyme present in unstimulated cells, since it has a Km of 1.2-2.0 μM, and is stimulated by snake venom. In L cells in which cAMP concentrations are elevated by treatment with prostaglandin E1, cAMP phosphodiesterase also accumulates. We conclude that intracellular concentrations of cAMP regulate the synthesis of cAMP-phosphodiesterase, and that cAMP functions as an inducer of the enzyme.

Keywords: 3T3, dibutyryl cyclic AMP, SV40-transformed cells, Michaelis constants, L cells, prostaglandin E1

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. BUTCHER R. W., SUTHERLAND E. W. Adenosine 3',5'-phosphate in biological materials. I. Purification and properties of cyclic 3',5'-nucleotide phosphodiesterase and use of this enzyme to characterize adenosine 3',5'-phosphate in human urine. J Biol Chem. 1962 Apr;237:1244–1250. [PubMed] [Google Scholar]
  2. Cheung W. Y. Cyclic 3',5'-nucleotide phosphodiesterase. Demonstration of an activator. Biochem Biophys Res Commun. 1970 Feb 6;38(3):533–538. doi: 10.1016/0006-291x(70)90747-3. [DOI] [PubMed] [Google Scholar]
  3. Cheung W. Y. Cyclic 3',5'-nucleotide phosphodiesterase. Evidence for and properties of a protein activator. J Biol Chem. 1971 May 10;246(9):2859–2869. [PubMed] [Google Scholar]
  4. Johnson G. S., Friedman R. M., Pastan I. Restoration of several morphological characteristics of normal fibroblasts in sarcoma cells treated with adenosine-3':5'-cyclic monphosphate and its derivatives. Proc Natl Acad Sci U S A. 1971 Feb;68(2):425–429. doi: 10.1073/pnas.68.2.425. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. LOWRY O. H., ROSEBROUGH N. J., FARR A. L., RANDALL R. J. Protein measurement with the Folin phenol reagent. J Biol Chem. 1951 Nov;193(1):265–275. [PubMed] [Google Scholar]
  6. Otten J., Johnson G. S., Pastan I. Cyclic AMP levels in fibroblasts: relationship to growth rate and contact inhibition of growth. Biochem Biophys Res Commun. 1971 Sep;44(5):1192–1198. doi: 10.1016/s0006-291x(71)80212-7. [DOI] [PubMed] [Google Scholar]
  7. Pastan I., Perlman R. L. Cyclic AMP in metabolism. Nat New Biol. 1971 Jan 6;229(1):5–7. doi: 10.1038/newbio229005a0. [DOI] [PubMed] [Google Scholar]
  8. Peery C. V., Johnson G. S., Pastan I. Adenyl cyclase in normal and transformed fibroblasts in tissue culture. Activation by prostaglandins. J Biol Chem. 1971 Sep 25;246(18):5785–5790. [PubMed] [Google Scholar]
  9. Thompson W. J., Appleman M. M. Multiple cyclic nucleotide phosphodiesterase activities from rat brain. Biochemistry. 1971 Jan 19;10(2):311–316. [PubMed] [Google Scholar]

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