Plant Shape: Molecular Aspects of Leaf Morphogenesis.

Plant morphogenesis is controlled by the integration of endogenous genetic programs and responses to exogenous signals. The leaf is a good subject for studying plant morphogenesis, the diversity of which is reflected in leaf shape. Early control of leaf shape relies on controlling leaf initiation at the shoot apical meristem (SAM), the rates and planes of cell division, and the polarity-dependent differentiation of leaf cells. Final leaf form involves coordination of the rates of division, enlargement, and differentiation of leaf cells. In addition, recent genetic studies have revealed a different mechanism that plays an important role in regulating leaf shape: the control of spatial and temporal expression by microRNA and programmed cell death. This brief review focuses on the genetic regulation of leaf shape, from the perspective of the spatial and temporal balance between cell division, cell enlargement, and cell differentiation, with special emphasis on our own studies. doi:10.1300/J411v17n01_09 [ABSTRACT FROM PUBLISHER]