Abstract
Leaf organizations in monocots are greatly diversified from those in dicots, and their structural relationships have been a matter of debate. In order to genetically dissect the leaf organization in monocots, we focused on "unifacial leaf" development, which was repeatedly evolved in a number of divergent species in monocots. Unifacial leaf develops bilaterally or radially symmetric leaf blade, in which leaf surface consists only of the abaxial side. From our observation, it was revealed that all of the leaf axes (i.e. adaxial-abaxial, distal-proximal, and central-lateral) are disorganized in unifacial leaves. Thus, comparative analyses between unifacial and normal bifacial leaf development should provide a number of information about leaf organization in monocots. In this report, we will discuss the mechanism of unifacial leaf development mainly based on the histological analyses, and will introduce our molecular genetic approaches to reveal the leaf organization in monocots.