Dxs expression in Morinda citrifolia cell suspension cultures to increase anthraquinones production

QUEVEDO, CV; PERASSOLO, M; BUSTO, VD; CARDILLO, AB; MARTÍNEZ, CA; GIULIETTI, AM; RODRÍGUEZ TALOU, JULIÁN

Carlos Paz, Córdoba, Argentina

Congreso; XLIV Reunión Anual de la SAIB; 2008

Sociedad Argentina de Investigación Bioquímica y Biología Molecular (SAIB)

Plant cell suspension cultures are attractive alternatives for large scale production of plant-derived natural products. Morinda citrifolia is able to produce Anthraquinones (AQs) that have a potential therapeutic use. AQs are anthracene derivatives whose basal structure, 9, 10-dioxoanthracene, can be substituted resulting in a diversity of structures. The A and B rings of AQs are synthetized from shikimic and á-ketoglutaric acids via the ischorismate/o-succinylbenzoate pathway. The C ring is originated from the 2-C-methyl-D-erythritol 4-phosphate pathway (MEP). 1-deoxy-D-Xylulose-5-phosphate synthase (DXS), the first enzyme in the MEP pathway converts pyruvate and glyceraldehyde 3-phosphate into 1-deoxy-D-Xylulose-5-phosphate. The aim of this work was to overexpress the DXS in M. citrifolia suspension cultures. The dxs cDNA from Catharantus roseus was inserted into the binary vector pMOG22-GUS, with hygromycin resistance, GUS reporter gene and the left and right T-DNA borders from A. tumefaciens. M citrifolia cell cultures were transformed by biolistic and A. tumefaciens strain LBA4404 methods. Transformation was confirmed by analysis of the GUS reporter gene. Transgenic cells lines showed significantly higher levels of AQs (21% and 30% after 3 and 6 days of culture; p>0.01) and higher DXS activity (60% in a 6 day-culture; p>0.05) compared to wild type cell lines.