Spatial regulation of trichome formation in Arabidopsis thaliana.

Trichomes in Arabidopsis are single-celled hairs that develop from epidermal cells regularly distributed on leaves, sepals and stems. Trichome formation in Arabidopsis is emerging as a genetic and molecular model system for the analysis of the spatial regulation of cell type specification in plants. In this review we focus on two aspects of trichome initiation: the regulation of organ and tissue layer specificity and the establishment of an epidermal spacing pattern.