IMPROVEMENT OF PHOTOSYNTHESIS AND STRESS TOLERANCE IN TRANSGENIC TOBACCO PLANTS BY EXPRESSING CYANOBACTERIAL FLAVODIIRON PROTEINS:

GÓMEZ R; CARRILLO N; HAJIREZAEI M-R; LODEYRO, A. F

Córdoba

Congreso; LII Reunión Anual de SAIB; 2016

Sociedad Argentina de Investigación en Bioquímica y Biología Molecular

IMPROVEMENT OFPHOTOSYNTHESIS AND STRESS TOLERANCE IN TRANSGENIC TOBACCO PLANTS BY EXPRESSINGCYANOBACTERIAL FLAVODIIRON PROTEINS: GÓMEZ, Rodrigo1*, LODEYRO, Anabella1,HAJIREZAEI,Mohammad-R.2, CARRILLO, Néstor11IBR -CONICET. Ocampo y Esmeralda, Rosario, Argentina. 2IPK Corrensstrasse3, Gatersleben, Germany. Flavodi-ironproteins (Flvs) are an large family of enzymes distributed among bacteria,archaea, protists and gymnosperm plants but absent from angiosperms. In the cyanobacteriumSynechoystis sp. PCC 6803, Flvs areencoded by four different genes (flv1-4) and form two functional heterodimers. Thefirst one, Flv1-Flv3 is a soluble NADPH-reductase which dissipates the excessof reduction power consuming NADPH and transferring the hydrides to dioxygen toform water in a single step. The action of these enzymes helps to avoidoxidative stress under unfavorable grown conditions. Using Agrobacteriummediated transformation we generated plants expressing Flv1-Flv3 dimer inchloroplasts. Those plants were used to evaluate stress tolerance andphotosynthetic performance under different growing conditions. As a result of in vivo chlorophyll fluorescence assayswe could show improvements in photosynthetic efficiency and faster dissipationof excessive energy of the transgenic compared with wild type plants, evenunder stressful conditions. Moreover, plants expressing Flv1-Flv3 displaybigger size than controls as we could determined by comparing the total leavesarea and fresh/dry weights. Taken together, these observations suggest anincrease in stress tolerance, faster adaptation to environmental fluctuations andenhance biomass production by expressing the cyanobacterial Flv1-Flv3 dimer inhigher plants.