Root Apical Meristems

Ji‐Young Lee, Duke University, Durham, North Carolina, USA
Philip N Benfey, Duke University, Durham, North Carolina, USA

Published online: April 2007

DOI: 10.1002/9780470015902.a0020121

Root apical meristems are populations of cells at the root tip that divide and form all the tissues of the root. The fate of divided cells is determined by positional signals. The iterative process of cell division, elongation and differentiation promotes root growth. An important aspect of growth is balancing the rate of cell division and differentiation, which is regulated by the quiescent centre.

Keywords: root; apical meristem; plant growth factors; positional signals

Figure 1. The atlas of the root tip of Arabidopsis thaliana as a representative root meristem. The organization of the root apical meristem is enlarged and major tissues are colour-coded. The first T-shape arrangement of divided cells (marked in bold lines) indicates the formative cell division.
Figure 2. Gene regulatory pathways for formative cell divisions and tissue specification. Gene regulatory pathways of (a) epidermis (b) endodermis and cortex (c) xylem and phloem and (d) QC are shown. , positive regulation; intcal , negative regulation; protein movement.
Figure 3. Regulation of root apical meristem organization by growth factors. (a) Stem cell maintenance by auxin and the gravitropic response by auxin and cytokinin. Green and blue lines respectively indicate the flow of auxin and cytokinin. The relative amounts are indicated by the line thickness. (b) The cytokinin regulation pathway and stele development.
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 Further Reading
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Related Sub-Topics:

Plant Development | Meristems | Genes, Molecules and Cellular Processes | Cell Differentiation and Stem Cells | Roots and Root Systems
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Article Title: Root Apical Meristems
 
How to Cite close
Lee, Ji‐Young, and Benfey, Philip N(Apr 2007) Root Apical Meristems. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1002/9780470015902.a0020121]