GIULIETTI Ana Maria
Involvement of the PLC/PKC pathway in chitosan-induced anthraquinone production by Rubia tinctorum L. cell cultures
VASCONSUELO, A.; GIULIETTI A M; PICOTTO G; RODRÍGUEZ TALOU J; BOLAND, R.
Año: 2003 vol. 165 p. 429 - 429
Abstract The signal transduction pathway by which the plant elicitor Chitosan affects secondary metabolite formation in Rubia tinctorum was investigated. Chitosan significantly stimulated (100%) anthraquinone (Aqs) synthesis in cultured R. tinctorum. The action of the elicitor could be greatly reduced by inhibition of phospholipase C (neomycin, U-73122) and protein kinase C (PKC) (calphostin C, bisindolylmaleimide, PKC down-regulation). The phorbol ester PMA mimicked the effects of Chitosan on Aqs production. Furthermore, a marked increase in PKC activity and PKC á associated to the cell membranes was observed in response to the elicitor. Compound 2-APB, a blocker of IP3 receptor-mediated release of Ca2+ from inner stores, inhibited Chitosan stimulation of Aqs formation. These results indicate that Chitosan modulation of Aqs levels in R. tinctorum involves activation of the phopholipase C/PKC pathway, with the Ca2+-dependent PKC á isoform playing a major role.