WOX5-IAA17 feedback circuit-mediated cellular auxin response is crucial for the patterning of root stem cell niches in arabidopsis Journal Article


Author(s): Tian, Huiyu; Wabnik, Krzysztof; Niu, Tiantian; Li, Hongjiang; Yu, Qianqian; Pollmann, Stephan; Vanneste, Steffen; Govaerts, Willy J; Rolčík, Jakub; Geisler, Markus; Friml, Jiří; Ding, Zhaojun
Article Title: WOX5-IAA17 feedback circuit-mediated cellular auxin response is crucial for the patterning of root stem cell niches in arabidopsis
Affiliation IST Austria
Abstract: In plants, the patterning of stem cell-enriched meristems requires a graded auxin response maximum that emerges from the concerted action of polar auxin transport, auxin biosynthesis, auxin metabolism, and cellular auxin response machinery. However, mechanisms underlying this auxin response maximum-mediated root stem cell maintenance are not fully understood. Here, we present unexpected evidence that WUSCHEL-RELATED HOMEOBOX 5 (WOX5) transcription factor modulates expression of auxin biosynthetic genes in the quiescent center (QC) of the root and thus provides a robust mechanism for the maintenance of auxin response maximum in the root tip. This WOX5 action is balanced through the activity of indole-3-acetic acid 17 (IAA17) auxin response repressor. Our combined genetic, cell biology, and computational modeling studies revealed a previously uncharacterized feedback loop linking WOX5-mediated auxin production to IAA17-dependent repression of auxin responses. This WOX5-IAA17 feedback circuit further assures the maintenance of auxin response maximum in the root tip and thereby contributes to the maintenance of distal stem cell (DSC) populations. Our experimental studies and in silico computer simulations both demonstrate that the WOX5-IAA17 feedback circuit is essential for the maintenance of auxin gradient in the root tip and the auxin-mediated root DSC differentiation.
Keywords: Computer Simulation; auxin maximum; IAA17/AXR3; root patterning; WOX5
Journal Title: Molecular Plant
Volume: 7
Issue 2
ISSN: 1752-9867
Publisher: Oxford University Press  
Date Published: 2014-02-01
Start Page: 277
End Page: 289
Sponsor: This work was supported by funding from: the National Natural Science Foundation of China (No. 31222005 and No. 31270327), the ‘Qilu Scholarship’ from Shandong University of China and from the Ministry of Education (11200081963024) and ‘1000-talents Plan’
DOI: 10.1093/mp/sst118
Notes: We acknowledge Ben Scheres, Tom J. Guilfoyle, and Thomas Laux sharing published materials and Keke Yi, Jürgen Kleine-Vehn, Seth Davis, and Xu Chen for critical reading of the manuscript. Z.D. and K.W. planned experiments. Z.D., K.W., H.T., T.N., S.P., and J.R. performed experiments. J.F., Z.D., M.G., Z.D., K.W., S.V., W.G., H.L., M.G., and J.F. analyzed the data. Z.D., K.W., and H.T. wrote the paper.
Open access: no