Kana Yamada

My research is to understand molecular evolution of Rubisco sub-units in Angiosperms.
RUBISCO is the most abundant protein and the key enzyme of photosynthesis. The different types of photosynthesis present in flowering plants have different efficiencies to concentrate and metabolite atmospheric CO₂. In particular, two types, called C3 and C4, have evolved multiple times in specific plant families like the grasses. The key enzyme in photosynthesis is RUBISCO, which is constituted of 8 small and 8 large subunits, encoded by the rbcS and rbcL genes, respectively. Both genes are involved in the CO₂ fixation pathway but the specific role of each gene is not known very well.
In this study, I investigate the evolution of the rbcS and rbcL genes for all flowering plant species. I estimate the occurrence of episodic events of positive selection along the branches of the phylogenetic trees of both genes to better understand the functional constraint during their evolution. I further estimate the coevolution between the two subunits to better understand the possible functional and structural interactions existing between them. The large-scale evolutionary analyses are complemented by a more detailed investigation of the evolution of this rbcL/rbcS complex in C3 and C4 transitions in grasses.