Transformation and characterization of Solanum lycopersicum lines for the expression of flavodiiron proteins from the moss Physcomitrium patens

In photosynthetic eukaryotes the linear electron flow (LEF) is the main mechanism for conversion of light into biochemical energy and involves the transport of electrons through a series of membrane-bound complexes (Photosystem II, Cytochrome b6f, Photosystem I). However, environmental changes and metabolic requirements caused the evolution of regulatory mechanisms like pseudo-cyclic electron flow (PCEF), which can be carried out by flavodiiron proteins (FLVs) because of their ability to divert electrons from Photosystem I to O2 during sudden changes in light intensity. Since FLVs are found throughout photosynthetic eukaryotes except for angiosperms, the aim of this thesis is to investigate the effects of the expression of FLVA/B proteins from Physcomitrium patens on Solanum lycopersicum, an angiosperm with relevant agronomic value. This project is articulated into three topics, first the isolation and photosynthetic characterization under different conditions of S. lycopersicum lines with constitutive FLVA/B expression. Then, the assessment of FLVs activity in different organs of the plant, focusing on the flower and the fruit. Finally, the generation of lines with leaf-specific FLVs expression, which involves the identification of appropriate promoters from leaf-specific genes and the incorporation of said promoters in a transcriptional activation system, later used to transform WT S. lycopersicum plants.