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Planta Med 2002; 68(11): 1039-1041
DOI: 10.1055/s-2002-35655
Letter
© Georg Thieme Verlag Stuttgart · New York

Differential Activation of Protein Kinase C Isoforms by Euxanthone, Revealed by an In Vivo Yeast Phenotypic Assay

Lucília Saraiva1 , 2 , Paula Fresco1 , Eugénia Pinto2 , Anake Kijjoa3 , Maria José Gonzalez4 , Jorge Gonçalves1
  • 1Serviço de Farmacologia, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal
  • 2Serviço de Microbiologia, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal
  • 3Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto, Portugal
  • 4Serviço de Química Orgânica, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal
Further Information

Publication History

Received: April 8, 2002

Accepted: June 1, 2002

Publication Date:
26 November 2002 (online)

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Abstract

The protein kinase C (PKC) modulatory effects of euxanthone, isolated from the wood of Cratoxylum maingayi, on isoforms α, βI, δ, η and ζ were characterised using an alternative in vivo yeast phenotypic assay. The present study shows that euxanthone can activate isoforms α, βI, δ, η and ζ, being more effective on PKC-βI, -δ, -η and -ζ than the established PKC activators used (the phorbol ester PMA and arachidonic acid for PKC-ζ). Furthermore, euxanthone presents differences on its potency towards individual PKC isoforms, showing a remarkable selectivity for PKC-ζ. These results can help to clarify the molecular basis of the euxanthone-mediated effects.

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Dr. Jorge Gonçalves

Laboratório de Farmacologia

Faculdade de Farmácia, Universidade do Porto

Rua Aníbal Cunha 164

P 4050-047 Porto, Portugal

Phone: +351 222078932

Fax: +35122078969

Email: jorge.goncalves@ff.up.pt