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A Plausible Mechanism for Auxin Patterning Along the Developing Root

Overview
Journal BMC Syst Biol
Publisher Biomed Central
Specialty Biology
Date 2010 Jul 29
PMID 20663170
Citations 34
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Abstract

Background: In plant roots, auxin is critical for patterning and morphogenesis. It regulates cell elongation and division, the development and maintenance of root apical meristems, and other processes. In Arabidopsis, auxin distribution along the central root axis has several maxima: in the root tip, in the basal meristem and at the shoot/root junction. The distal maximum in the root tip maintains the stem cell niche. Proximal maxima may trigger lateral or adventitious root initiation.

Results: We propose a reflected flow mechanism for the formation of the auxin maximum in the root apical meristem. The mechanism is based on auxin's known activation and inhibition of expressed PIN family auxin carriers at low and high auxin levels, respectively. Simulations showed that these regulatory interactions are sufficient for self-organization of the auxin distribution pattern along the central root axis under varying conditions. The mathematical model was extended with rules for discontinuous cell dynamics so that cell divisions were also governed by auxin, and by another morphogen Division Factor which combines the actions of cytokinin and ethylene on cell division in the root. The positional information specified by the gradients of these two morphogens is able to explain root patterning along the central root axis.

Conclusion: We present here a plausible mechanism for auxin patterning along the developing root, that may provide for self-organization of the distal auxin maximum when the reverse fountain has not yet been formed or has been disrupted. In addition, the proximal maxima are formed under the reflected flow mechanism in response to periods of increasing auxin flow from the growing shoot. These events may predetermine lateral root initiation in a rhyzotactic pattern. Another outcome of the reflected flow mechanism - the predominance of lateral or adventitious roots in different plant species - may be based on the different efficiencies with which auxin inhibits its own transport in different species, thereby distinguishing two main types of plant root architecture: taproot vs. fibrous.

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References
1.
Smith R, Guyomarch S, Mandel T, Reinhardt D, Kuhlemeier C, Prusinkiewicz P . A plausible model of phyllotaxis. Proc Natl Acad Sci U S A. 2006; 103(5):1301-6. PMC: 1345713. DOI: 10.1073/pnas.0510457103. View

2.
van den Berg C, Willemsen V, HAGE W, Weisbeek P, Scheres B . Cell fate in the Arabidopsis root meristem determined by directional signalling. Nature. 1995; 378(6552):62-5. DOI: 10.1038/378062a0. View

3.
De Smet I, Tetsumura T, De Rybel B, Frei Dit Frey N, Laplaze L, Casimiro I . Auxin-dependent regulation of lateral root positioning in the basal meristem of Arabidopsis. Development. 2007; 134(4):681-90. DOI: 10.1242/dev.02753. View

4.
Merks R, Van de Peer Y, Inze D, Beemster G . Canalization without flux sensors: a traveling-wave hypothesis. Trends Plant Sci. 2007; 12(9):384-90. DOI: 10.1016/j.tplants.2007.08.004. View

5.
Sabatini S, Beis D, Wolkenfelt H, Murfett J, Guilfoyle T, Malamy J . An auxin-dependent distal organizer of pattern and polarity in the Arabidopsis root. Cell. 1999; 99(5):463-72. DOI: 10.1016/s0092-8674(00)81535-4. View