Abstract
One of the longstanding questions for developmental biologists is how organisms acquire shape and size. In leaves of several Arabidopsis mutants, a decrease in cell number triggers an increase in the final cell volume. As a result, the decrease in leaf size is less great than the decrease in cell number; therefore, we call this phenomenon compensation. Although compensation has been reported previously, far less is known about its molecular mechanism(s). To explain the mechanism of the compensation, we hypothesized unknown co-ordinating systems for proliferation and enlargement of leaf cells. When cell proliferation is decreased by some obstacles, the co-ordinating system might trigger the compensation. In order to unveil the molecular mechanism(s) of compensation, we screened several mutants exhibiting the compensation and we successfully isolated 5 mutants that show typical compensation. Cloning of responsible genes by map-based cloning technique and detailed analyses of the compensation mutants will be reported.
