During the second stage in photosynthesis, known as the Calvin Cycle, carbon is converted into glucose. This glucose is then used to synthesize the carbohydrates, proteins, lipids and many other compounds used in the construction and maintenance of the plant.
The Calvin cycle consists of many steps, each catalyzed by a different enzyme. Computer modeling and experimental measurements suggest that investment of resources between the enzymes of the cycle is not optimized for maximum photosynthetic productivity. RIPE is increasing and decreasing the gene expression of several enzymes within the leaf to achieve an optimized photosynthetic system.