Abstract
Photosynthetic organisms exist under various light intensities. This ability is purchased by two mechanisms; the dissipation of excess light energy as heat and the adjustment of the antenna size.
Plants have large antenna of photosystems when they grow under low light intensities, and small antenna under high light. However, the mechanisms and the physiological roles of the adjustment of the antenna size have not been fully understood. We found that expression of chlorohyllide a oxygenase (CAO) is regulated by light intensities, and that the level of CAO mRNA was strongly correlated to antenna size. CAO over expressed A. thaliana completely lost the ability to alter the antenna size responding to light intensities. Using these transgenic plants, we will talk about the mechanisms and the physiological roles of adjusting the antenna size.
