Abstract
The metabolism of source organs in plants change during the development of the sink organs. The regulation of this metabolism is important in the control of crop productivity. To elucidate these regulation systems, we constructed model experiments using Arabidopsis to analyze metabolic and gene expression changes during leaf-stage progression and after removal of the reproductive organs. Leaf gene expression levels and content of major amino acids, both of which decreased during leaf-stage progression, increased after removal of the reproductive organs. In particular, the levels of expression of cytokinin-biosynthesis genes and cytokinin-responsive genes and the cytokinin content increased after removal of the reproductive organs. Analysis of plants with knockout of a cytokinin-biosynthetic gene (AtIPT3) and a cytokinin-receptor gene (AHK3) suggest that cytokinins regulate communication between reproductive and vegetative organs.
