Developmental regulation of protein kinase A expression and activity in Schistosoma mansoni

Brett E. Swierczewski, Stephen J. Davies*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

18 Scopus citations


cAMP-dependent protein kinases (PKAs) are the main transducers of cAMP signalling in eukaryotic cells. Recently we reported the identification and characterisation of a PKA catalytic subunit (SmPKA-C) in Schistosoma mansoni that is required for adult schistosome viability in vitro. To gain further insights into the role of SmPKA-C in biological processes during the schistosome life cycle, we undertook a quantitative analysis of SmPKA-C mRNA expression in different life cycle stages. Our data shows that SmPKA-C mRNA expression is developmentally regulated, with the highest levels of expression in cercariae and adult female worms. To evaluate the biological role of SmPKA-C in these developmental stages, cercariae and adult worms were treated with various concentrations of PKA inhibitors. Treatment of cercariae with H-89 or PKI 14-22 amide resulted in loss of viability suggesting that, as in adults, PKA is an essential enzyme activity in this infectious larval stage. In adult worms, in vitro exposure to sub-lethal concentrations of H-89 or PKI 14-22 amide resulted in inhibition of egg production in a dose-dependent manner. Furthermore, using a murine model of schistosome infection where S. mansoni fecundity is impaired, we show that reduced rates of egg production in vivo correlate with significant reductions in SmPKA-C mRNA expression and PKA activity. Finally, restoration of parasite egg production in vivo also resulted in normalisation of SmPKA-C mRNA expression and PKA activity. Taken together, our data suggest that PKA signalling is required for cercarial viability and may play a specific role in the reproductive activity of adult worms.

Original languageEnglish
Pages (from-to)929-935
Number of pages7
JournalInternational Journal for Parasitology
Issue number8
StatePublished - Jul 2010
Externally publishedYes


  • Blood fluke
  • Parasite development
  • Protein kinase A
  • Reproductive biology
  • Schistosoma mansoni
  • Schistosome


Dive into the research topics of 'Developmental regulation of protein kinase A expression and activity in Schistosoma mansoni'. Together they form a unique fingerprint.

Cite this