Submitted to: Trends in Plant Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/18/2003
Publication Date: 7/21/2003
Citation: CARLES, C.C., FLETCHER, J.C. SHOOT APICAL MERISTEM MAINTENANCE: THE ART OF A DYNAMIC BALANCE. TRENDS IN PLANT SCIENCE. 2003. Interpretive Summary: This article is a comprehensive review of the recent scientific literature detailing 1) the molecular mechanisms that permit stem cells to be maintained at the growing tips of plants in order to generate new leaves and flowers, and 2) the temporal mechanisms that stop stem cell production to allow flower development to proceed.
Technical Abstract: The aerial structure of higher plants derives from cells at the tip of the stem, in the shoot apical meristem (SAM). Throughout the life of a plant, the SAM produces stem tissues and lateral organs, and also regenerates itself. For correct growth, the plant must maintain a constant flow of cells through the meristem, where the input of dividing pluripotent stem cells offsets the output of differentiating cells. This flow depends on extracellular signaling within the SAM, governed by a spatial regulatory feedback loop that maintains a reservoir of stem cells, and on factors that prevent meristem cells from differentiating prematurely. The terminating floral meristem incorporates the spatial regulation scheme into a temporal regulation pathway involving flower patterning factors.