Identification of a novel isoform of the cyclic-nucleotide phosphodiesterase PDE3A expressed in vascular smooth-muscle myocytes

Research output: Contribution to journalArticle

Abstract

We have identified a new cyclic-nucleotide phosphodiesterase isoform, PDE3A, and cloned its cDNA from cultured aortic myocytes. The nucleotide sequence of its coding region is similar to that of the previously cloned myocardial isoform except for the absence of the initial 300-400 nt that are present in the latter, as confirmed by reverse-transcriptase-mediated PCR, 5' rapid amplification of cDNA ends and a ribonuclease protection assay. Expression in Spodoptera frugiperda (Sf9) cells yields a protein with catalytic activity and inhibitor sensitivity typical of the PDE3 family. The recombinant protein's molecular mass of approx. 131 kDa is compatible with translation from an ATG sequence corresponding to nt 436-438 of the myocardial PDE3A coding region. Antibodies against residues 424-460 (nt 1270-1380) and 1125-1141 (nt 3373-3423) of the myocardial isoform react with an approx. 118 kDa band in Western blots of homogenates of human aortic myocytes, whereas antibodies against residues 29-42 (nt 85-126) do not react with any bands in these homogenates. Our results suggest that a vascular smooth-muscle isoform ('PDE3A2') is a product of the same gene as the longer myocardial ('PDE3A1') and the shorter placental ('PDE3A3') isoforms and is generated pre-translationally in a manner that results in the absence of the 145 N-terminal amino acids of PDE3A1.

Details

Authors
  • Young-Hun Choi
  • Dag Ekholm
  • Judith Krall
  • Faiyaz Ahmad
  • Eva Degerman
  • Vincent C. Manganiello
  • Matthew A. Movsesian
Organisations
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Biochemistry and Molecular Biology

Keywords

  • intracellular signalling, protein phosphorylation, second messengers, vasodilation
Original languageEnglish
Pages (from-to)41-50
JournalBiochemical Journal
Volume353
Issue numberPt 1
Publication statusPublished - 2001
Publication categoryResearch
Peer-reviewedYes