First published online January 26, 2007
Development 134, 401e (2007)
© The Company of Biologists Limited
Auxin: putting down roots
The initiation of new lateral roots in Arabidopsis occurs at
predictable distances from the growing tip and depends on auxin transport and
redistribution. However, the precise mechanism that regulates the positioning
of new roots has remained elusive. Tom Beeckman and colleagues now show, on
p. 681, how oscillating
waves of auxin accumulation and response in the cells that exit the root
meristem bring about the regular left-right alternating pattern of lateral
root development along the main root axis. AUX1, an auxin influx carrier, is
essential for this left-right patterning in response to gravity; it transports
auxin from cells exiting the root tip back to those still in the root tip.
Cells between the growing tip and the meristem display an oscillatory
responsiveness to auxin with a periodicity of 15 hours. The authors
demonstrate that this peak in auxin responsiveness corresponds precisely with
the formation of a lateral root. Thus cells are primed for root development
while still in the root tip.
Related articles in Development:
- Auxin-dependent regulation of lateral root positioning in the basal meristem of Arabidopsis
- Ive De Smet, Takuya Tetsumura, Bert De Rybel, Nicolas Frei dit Frey, Laurent Laplaze, Ilda Casimiro, Ranjan Swarup, Mirande Naudts, Steffen Vanneste, Dominique Audenaert, Dirk Inzé, Malcolm J. Bennett, and Tom Beeckman
Development 2007 134: 681-690.
[Abstract]
[Full Text]
