Talk global, act local-patterning the Arabidopsis embryo.
The primary axis and main tissue types of Arabidopsis are laid down in the early embryo. Apical-to-basal auxin flux functions as a global organizer of the axis, and recent reports are clarifying our mechanistic understanding of how a graded auxin distribution is generated and interpreted. Polar targeting of PIN transporters in the cells of the embryo is dynamic and linked to their phosphorylation status, suggesting a flexible mechanism for regulating auxin flux in space and time. PLETHORA transcription factors then interpret the graded auxin distribution to provide positional values along the axis in a dose-dependent manner. A comparable framework for tissue patterning in the radial dimension is still lacking, although cell surface signaling probably plays a key role.
Nawy
Tal
T
Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, United States. nawy@cshl.edu
Lukowitz
Wolfgang
W
Bayer
Martin
M
D017360:Arabidopsis / Q000196:embryology* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000378:metabolism; D019521:Body Patterning / Q000502:physiology*; D002450:Cell Communication / Q000502:physiology; D007210:Indoleacetic Acids / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism
D029681:Arabidopsis Proteins; D007210:Indoleacetic Acids; C493246:PLT1 protein, Arabidopsis; C493247:PLT2 protein, Arabidopsis; D014157:Transcription Factors