Anthraquinones elicitation and oxidative burst in Rubia Tinctorum cell suspensions

PERASSOLO, M; BUSTO, VD; QUVEDO, CV; CARDILLO, AB; MARTINEZ, CA; CUADRADO, V; MERINI, LJ; RODRIGUEZ TALOU, J

Mar del Plata - Buenos Aires

Congreso; XLIII Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (S.A.I.B.).; 2007

In Rubia tinctorum cell suspensions, anthraquinones (AQs) production is induced by elicitors such as chitosan. This defense response also includes generation of reactive oxygen species (ROS) and cell death. It has been recently showed that chitosan induction of anthraquinone synthesis in R. tinctorum involves the stimulation of PLC, intracellular Ca2+ mobilization and PI3K, which mediates MAPK activation. In the present work we study the relationship between elicitation, oxidative burst and cell death. Elicitation with chitosan (200 mg/l) stimulates AQs synthesis in R. tinctorum L. cultures at 24 and 48 hr. An increase in H2O2 production at 6 and 24 hr was observed and correlated with higher levels of cell death. Addition of chitosan and diphenylene iodonium (DPI), an inhibitor of H2O2 generation, resulted in a decrease in cell death and H2O2 production. In both treatments similar levels of AQs accumulation were observed. In cultures treated with chitosan and lanthanum chloride, an intracellular calcium channel blocker, cell death and AQs production decreased showing that both processes require an increase in cytosolic calcium levels. The relationship between elicitation and ROS generation is under study.