How do transcription factors control the fates of cells that express them? One class of plant transcription factors has recently been shown to function by regulating the synthesis of cytokinin and gibberellin hormones--mobile molecules more usually associated with long-distance signalling.

During postembryonic development, all organs of a plant are ultimately derived from a few pluripotent stem cells found in specialized structures called apical meristems. Here we discuss our current knowledge about the regulation of plant stem cells and their environments with main emphasis on the shoot apical meristem of Arabidopsis thaliana. Recent studies suggest that stem cells are localized...

A major source of diversity in flowering plant form is the extensive variability of leaf shape and size. Leaf formation is initiated by recruitment of a handful of cells flanking the shoot apical meristem (SAM) to develop into a complex three-dimensional structure. Leaf organogenesis depends on activities of several distinct meristems that are established and spatiotemporally differentiated aft...

Genetic and molecular analysis in Arabidopsis has identified components of a putative cell signalling pathway that appears to regulate the balance between stem cell proliferation and fate specification in meristems.