Abstract
During plant leaf development, cell proliferation in leaf primordia and following cell expansion driven by vacuolation occurs in coordinated manner. When the cell proliferation is inhibited, extraordinary cell expansion is often induced. This phenomenon, called compensation syndrome, might reflect endogenous mechanism that coordinates cell proliferation and cell expansion. Despite extensive studies in recent years, this mechanism remains largely unknown.
To analyze this mechanism, we investigated the mutants that show increased cell number and decreased cell size, opposite to compensation. We isolated four such Arabidopsis mutants. Time-course analysis of the cell number and cell size in the 1st leaf revealed that all the mutants have longer cell proliferation period. As to the cell expansion, one mutant showed normal speed with shorter expansion period and the others showed slower expansion speed than the wild type. The latter indicates elevated cell proliferation activity attenuates the cell expansion. Further analyses are now in progress.
