RIVERSIDE, Calif. Plant stem-cells are master cells located at the tip of the stem and are part of a structure called the shoot apical meristem (SAM). Here, the stem cellsall clumped togetherdivide throughout the life of the plant to give rise to other cells, resulting in the formation of above-ground organs such as leaves, flowers, branches and stem.
But despite the important role the stem cells play in plant development, their molecular composition has eluded researchers for long.
Now, working on Arabidopsis, a mustard-like plant that is a model for studying plant biology, a team of researchers at UC Riverside has identified all the genes expressed in the plant's stem cells.
The researchers also identified all the genes expressed in two other SAM cells: niche cells (which are located just beneath the stem cells and which provide signals that regulate the stem cells), and differentiating cells (which are generated by, and surround, the stem cells).
The final product of the researchers' work is a genome-scale, expression map of SAMan achievement that paves the way to developing better varieties of crops and plants.
Besides revealing the molecular pathways that stem cells employ, the discovery also can help scientists better understand why stem cellsin both plants and animalsgive rise to specialized cells at all.
Study results appear online this week in the early edition of the Proceedings of the National Academy of Sciences.
"Our study is the first to reveal the stem-cell signatures for any plant and the first to provide a global view of which genes are expressed, and where, within the SAM," said G. Venugopala Reddy, the lead author of the study and an assistant professor of plant cell biology in the Department of Botany and Plant Sciences. "Since SAM stem-cells are responsible for for
|Contact: Iqbal Pittalwala|
University of California - Riverside