RT Journal Article
SR Electronic
T1 Expression of human recombinant cAMP phosphodiesterase isozyme IV reverses growth arrest phenotypes in phosphodiesterase-deficient yeast.
JF Molecular Pharmacology
JO Mol Pharmacol
FD American Society for Pharmacology and Experimental Therapeutics
SP 109
OP 113
VO 39
IS 2
A1 M M McHale
A1 L B Cieslinski
A1 W K Eng
A1 R K Johnson
A1 T J Torphy
A1 G P Livi
YR 1991
UL http://molpharm.aspetjournals.org/content/39/2/109.abstract
AB The low-Km cAMP-specific phosphodiesterases (PDEases) are of great pharmacological significance because of their involvement in regulating cAMP concentrations, which, in turn, are responsible for mediating the cellular response to extracellular signals such as hormones and neurotransmitters. We recently reported the isolation of a cDNA clone that encodes a human monocyte low-Km, rolipram-sensitive, cAMP PDEase (isozyme IV). We have engineered the inducible expression of this human PDEase in yeast. Cells of Saccharomyces cerevisiae contain two genes that encode cAMP PDEases. PDEase-deficient mutants are viable but exhibit specific growth arrest phenotypes associated with elevated intracellular cAMP content; these phenotypes include heat shock sensitivity and the inability to grow on acetate as a carbon source. We show that functional expression of our human cAMP PDEase in a genetically engineered PDEase-deficient strain of S. cerevisiae reverses these aberrant phenotypes. Furthermore, under conditions for growth arrest, rolipram is cytotoxic to PDEase-deficient mutants expressing the human cAMP PDEase, indicating that it is capable of inhibiting the human recombinant enzyme in vivo. This system can be used in the development of a yeast cell-based assay for isozyme-selective inhibitors of the human recombinant cAMP PDEase.