The Arabidopsis Root Tip (Phospho)Proteomes at Growth-Promoting versus Growth-Repressing Conditions Reveal Novel Root Growth Regulators
Natalia Nikonorova,
Evan Murphy,
Cassio Flavio Fonseca de Lima,
Shanshuo Zhu,
Brigitte van de Cotte,
Lam Dai Vu,
Daria Balcerowicz,
Lanxin Li,
Xiangpei Kong,
Gieljan De Rop,
Tom Beeckman,
Jiří Friml,
Kris Vissenberg,
Peter C. Morris,
Zhaojun Ding,
Ive De Smet
Affiliations
Natalia Nikonorova
Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
Evan Murphy
Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, Loughborough LE12 5RD, UK
Cassio Flavio Fonseca de Lima
Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
Shanshuo Zhu
Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
Brigitte van de Cotte
Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
Lam Dai Vu
Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
Daria Balcerowicz
Integrated Molecular Plant Physiology Research, Biology Department, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium
Lanxin Li
Institute of Science and Technology (IST) Austria, 3400 Klosterneuburg, Austria
Xiangpei Kong
The Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao 266237, China
Gieljan De Rop
Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
Tom Beeckman
Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
Jiří Friml
Institute of Science and Technology (IST) Austria, 3400 Klosterneuburg, Austria
Kris Vissenberg
Integrated Molecular Plant Physiology Research, Biology Department, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium
Peter C. Morris
Institute for Life and Earth Sciences, School of Energy, Geosciences, Infrastructure and Society, Heriot-Watt University, Riccarton, Edinburgh EH14 4AS, UK
Zhaojun Ding
The Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao 266237, China
Ive De Smet
Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
Auxin plays a dual role in growth regulation and, depending on the tissue and concentration of the hormone, it can either promote or inhibit division and expansion processes in plants. Recent studies have revealed that, beyond transcriptional reprogramming, alternative auxin-controlled mechanisms regulate root growth. Here, we explored the impact of different concentrations of the synthetic auxin NAA that establish growth-promoting and -repressing conditions on the root tip proteome and phosphoproteome, generating a unique resource. From the phosphoproteome data, we pinpointed (novel) growth regulators, such as the RALF34-THE1 module. Our results, together with previously published studies, suggest that auxin, H+-ATPases, cell wall modifications and cell wall sensing receptor-like kinases are tightly embedded in a pathway regulating cell elongation. Furthermore, our study assigned a novel role to MKK2 as a regulator of primary root growth and a (potential) regulator of auxin biosynthesis and signalling, and suggests the importance of the MKK2 Thr31 phosphorylation site for growth regulation in the Arabidopsis root tip.
