Scientists Map Plant Stem Cell Genes

Plants have their own version of animal stem cells. Plant stem cells, or meristems, can morph themselves into almost any cell type. Above-ground plant parts such as flowers, leaves and seeds are generated by shoot apical meristems (SAM), a specific type of meristems located at the tip of the stem. Unlike animal stem cells, shoot apical meristems are capable of producing any type of cell as long as the plant is growing. Despite the important roles of stem cells, their molecular composition has long eluded scientists.

Working with the plant model Arabidopsis thaliana, G.V. Reddy and colleagues at the University of California Riverside have identified all the genes expressed in plant stem cells. They have also pinpointed the genes expressed in differentiating cells and niche cells, cells that regulate plant meristematic cell fate decisions. The findings will help scientists better understand the molecular pathways employed by stem cells and may pave the way for the development of better crop and plant varieties. The study will also help scientists gain insights into basic questions such as what constitutes stem cell identity and why stem cells in both plants and animals give rise to specialized cells at all.

The paper appears in the early edition of PNAS. For more information, read http://newsroom.ucr.edu/cgi-bin/display.cgi?id=2029