Cell-cell communication in Arabidopsis early embryogenesis.

The basic body plan of the adult plant is established during embryogenesis, resulting in the juvenile form of the seedling. Arabidopsis embryogenesis is distinguished by a highly regular pattern of cell divisions. Some of these divisions are asymmetric, generating daughter cells with different fates. However, their subsequent differentiation might still depend on cell-cell communication to be fully accomplished or maintained. In some cases, cell fate specification solely depends on cell-cell communication that in general plays an important role in the generation of positional information within the embryo. Although auxin-dependent signalling has received much attention, other ways of cell-cell communication have also been demonstrated or suggested. This review focuses on aspects of pattern formation and cell-cell communication during Arabidopsis embryogenesis up to the mid-globular stage of development.