Development of stress tolerance in crop plants by introduction of a cyanobacterial flavodoxin

ZURBRIGGEN M; TOGNETTI V; VALLE E; HAJIREZAEI MR; CARRILLO N

Mar del Plata, Argentina.

Congreso; XLIII Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB); 2007

Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB)

Plants growing under natural conditions unavoidably face episodic situations of environmental stress in the course of their life times. They have developed numerous strategies to survive in such adverse conditions. Crops, instead, are selected by humans for their high productivity in agriculture, but this is usually not accompanied by increased resistance to hostile environments (diseases, unfavorable climates or inappropriate soils) that are responsible for most agricultural losses. Oxidative stress leads to decreased levels of the electron transport protein ferredoxin (Fd). Under these conditions, cyanobacteria and some algae induce the synthesis of the flavoprotein flavodoxin (Fld), which can provide a functional substitution of Fd in many of its crucial functions in the chloroplasts. Transgenic tobacco plants expressing Anabaena Fld in chloroplasts displayed enhanced tolerance to oxidative stress conditions and iron deficiency. Transformation of related Solanaceae (tomato, potato) yielded essentially the same tolerant phenotypes when challenged with the redox cycling herbicide paraquat and exposed to drought conditions. Protocols to incorporate Fld into several other crops, including cereals and Brassicaceae are currently under way. The Fld gene-based strategy could be a useful biotechnological tool to improve crop yields and to gain at least some wastelands for agriculture.