Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.


Logo for

Science 312 (5777): 1218-1220

Copyright © 2006 by the American Association for the Advancement of Science

AXR4 Is Required for Localization of the Auxin Influx Facilitator AUX1

S. Dharmasiri,1*{dagger} R. Swarup,2* K. Mockaitis,1* N. Dharmasiri,1{dagger} S. K. Singh,3 M. Kowalchyk,3 A. Marchant,3 S. Mills,4 G. Sandberg,3 M. J. Bennett,2{ddagger} M. Estelle1{ddagger}

Abstract: The AUX1 and PIN auxin influx and efflux facilitators are key regulators of root growth and development. For root gravitropism to occur, AUX1 and PIN2 must transport auxin via the lateral root cap to elongating epidermal cells. Genetic studies suggest that AXR4 functions in the same pathway as AUX1. Here we show that AXR4 is a previously unidentified accessory protein of the endoplasmic reticulum (ER) that regulates localization of AUX1 but not of PIN proteins. Loss of AXR4 resulted in abnormal accumulation of AUX1 in the ER of epidermal cells, indicating that the axr4 agravitropic phenotype is caused by defective AUX1 trafficking in the root epidermis.

1 Department of Biology, Indiana University, Bloomington, IN 47405, USA.
2 School of Biosciences, University of Nottingham, Loughborough LE12 5RD, UK.
3 Umeå Plant Science Centre, SLU, Umeå, Sweden.
4 School of Computer Science and Information Technology, University of Nottingham, Nottingham NG7 2UH, UK.

* These authors contributed equally to this work.

{dagger} Present address: Department of Biology, Texas State University–San Marcos, San Marcos, TX 78666, USA.

{ddagger} To whom correspondence should be addressed. E-mail: malcolm.bennett{at} (M.J.B.), maestell{at} (M.E.)

Auxin distribution is differentially affected by nitrate in roots of two rice cultivars differing in responsiveness to nitrogen.
W. Song, H. Sun, J. Li, X. Gong, S. Huang, X. Zhu, Y. Zhang, and G. Xu (2013)
Ann. Bot. 112, 1383-1393
   Abstract »    Full Text »    PDF »
Arabidopsis aux1rcr1 mutation alters AUXIN RESISTANT1 targeting and prevents expression of the auxin reporter DR5:GUS in the root apex.
J. Yu and C.-K. Wen (2013)
J. Exp. Bot. 64, 921-933
   Abstract »    Full Text »    PDF »
Auxin controls petal initiation in Arabidopsis.
E. R. Lampugnani, A. Kilinc, and D. R. Smyth (2013)
Development 140, 185-194
   Abstract »    Full Text »    PDF »
AUX/LAX Genes Encode a Family of Auxin Influx Transporters That Perform Distinct Functions during Arabidopsis Development.
B. Peret, K. Swarup, A. Ferguson, M. Seth, Y. Yang, S. Dhondt, N. James, I. Casimiro, P. Perry, A. Syed, et al. (2012)
PLANT CELL 24, 2874-2885
   Abstract »    Full Text »    PDF »
Polar localization of a symbiosis-specific phosphate transporter is mediated by a transient reorientation of secretion.
N. Pumplin, X. Zhang, R. D. Noar, and M. J. Harrison (2012)
PNAS 109, E665-E672
   Abstract »    Full Text »    PDF »
Regulation of Root Greening by Light and Auxin/Cytokinin Signaling in Arabidopsis.
K. Kobayashi, S. Baba, T. Obayashi, M. Sato, K. Toyooka, M. Keranen, E.-M. Aro, H. Fukaki, H. Ohta, K. Sugimoto, et al. (2012)
PLANT CELL 24, 1081-1095
   Abstract »    Full Text »    PDF »
Sphingolipids Containing Very-Long-Chain Fatty Acids Define a Secretory Pathway for Specific Polar Plasma Membrane Protein Targeting in Arabidopsis.
J. E. Markham, D. Molino, L. Gissot, Y. Bellec, K. Hematy, J. Marion, K. Belcram, J.-C. Palauqui, B. Satiat-JeuneMaitre, and J.-D. Faure (2011)
PLANT CELL 23, 2362-2378
   Abstract »    Full Text »    PDF »
Serotonin, a Tryptophan-Derived Signal Conserved in Plants and Animals, Regulates Root System Architecture Probably Acting as a Natural Auxin Inhibitor in Arabidopsis thaliana.
R. Pelagio-Flores, R. Ortiz-Castro, A. Mendez-Bravo, L. Macias-Rodriguez, and J. Lopez-Bucio (2011)
Plant Cell Physiol. 52, 490-508
   Abstract »    Full Text »    PDF »
RCD1 and SRO1 are necessary to maintain meristematic fate in Arabidopsis thaliana.
S. Teotia and R. S. Lamb (2011)
J. Exp. Bot. 62, 1271-1284
   Abstract »    Full Text »    PDF »
Endoplasmic Reticulum: The Rising Compartment in Auxin Biology.
J. Friml and A. R. Jones (2010)
Plant Physiology 154, 458-462
   Full Text »    PDF »
The march of the PINs: developmental plasticity by dynamic polar targeting in plant cells.
W. Grunewald and J. Friml (2010)
EMBO J. 29, 2700-2714
   Abstract »    Full Text »    PDF »
Arabidopsis ROOT UVB SENSITIVE2/WEAK AUXIN RESPONSE1 Is Required for Polar Auxin Transport.
L. Ge, W. Peer, S. Robert, R. Swarup, S. Ye, M. Prigge, J. D. Cohen, J. Friml, A. Murphy, D. Tang, et al. (2010)
PLANT CELL 22, 1749-1761
   Abstract »    Full Text »    PDF »
The RNA Binding Protein Tudor-SN Is Essential for Stress Tolerance and Stabilizes Levels of Stress-Responsive mRNAs Encoding Secreted Proteins in Arabidopsis.
N. F. dit Frey, P. Muller, F. Jammes, D. Kizis, J. Leung, C. Perrot-Rechenmann, and M. W. Bianchi (2010)
PLANT CELL 22, 1575-1591
   Abstract »    Full Text »    PDF »
Auxin Transporters--Why So Many?.
E. Zazimalova, A. S. Murphy, H. Yang, K. Hoyerova, and P. Hosek (2010)
Cold Spring Harb Perspect Biol 2, a001552
   Abstract »    Full Text »    PDF »
Arabidopsis Auxin Mutants Are Compromised in Systemic Acquired Resistance and Exhibit Aberrant Accumulation of Various Indolic Compounds.
W. M. Truman, M. H. Bennett, C. G. N. Turnbull, and M. R. Grant (2010)
Plant Physiology 152, 1562-1573
   Abstract »    Full Text »    PDF »
The auxin influx carriers AUX1 and LAX3 are involved in auxin-ethylene interactions during apical hook development in Arabidopsis thaliana seedlings.
F. Vandenbussche, J. Petrasek, P. Zadnikova, K. Hoyerova, B. Pesek, V. Raz, R. Swarup, M. Bennett, E. Zazimalova, E. Benkova, et al. (2010)
Development 137, 597-606
   Abstract »    Full Text »    PDF »
Mild salinity stimulates a stress-induced morphogenic response in Arabidopsis thaliana roots.
G. Zolla, Y. M. Heimer, and S. Barak (2010)
J. Exp. Bot. 61, 211-224
   Abstract »    Full Text »    PDF »
Mechanical Stimuli Modulate Lateral Root Organogenesis.
G. L. Richter, G. B. Monshausen, A. Krol, and S. Gilroy (2009)
Plant Physiology 151, 1855-1866
   Abstract »    Full Text »    PDF »
Auxin transport routes in plant development.
J. Petrasek and J. Friml (2009)
Development 136, 2675-2688
   Abstract »    Full Text »    PDF »
Abscisic Acid Represses Growth of the Arabidopsis Embryonic Axis after Germination by Enhancing Auxin Signaling.
C. Belin, C. Megies, E. Hauserova, and L. Lopez-Molina (2009)
PLANT CELL 21, 2253-2268
   Abstract »    Full Text »    PDF »
Arabidopsis ASA1 Is Important for Jasmonate-Mediated Regulation of Auxin Biosynthesis and Transport during Lateral Root Formation.
J. Sun, Y. Xu, S. Ye, H. Jiang, Q. Chen, F. Liu, W. Zhou, R. Chen, X. Li, O. Tietz, et al. (2009)
PLANT CELL 21, 1495-1511
   Abstract »    Full Text »    PDF »
Post-transcriptional regulation of auxin transport proteins: cellular trafficking, protein phosphorylation, protein maturation, ubiquitination, and membrane composition.
B. Titapiwatanakun and A. S. Murphy (2009)
J. Exp. Bot. 60, 1093-1107
   Abstract »    Full Text »    PDF »
Cellular and Molecular Requirements for Polar PIN Targeting and Transcytosis in Plants.
J. Kleine-Vehn, L. Langowski, J. Wisniewska, P. Dhonukshe, P. B Brewer, and J. Friml (2008)
Mol Plant 1, 1056-1066
   Abstract »    Full Text »    PDF »
The Binding of Auxin to the Arabidopsis Auxin Influx Transporter AUX1.
D. J. Carrier, N. T. A. Bakar, R. Swarup, R. Callaghan, R. M. Napier, M. J. Bennett, and I. D. Kerr (2008)
Plant Physiology 148, 529-535
   Abstract »    Full Text »    PDF »
A new mutant of Arabidopsis disturbed in its roots, right-handed slanting, and gravitropism defines a gene that encodes a heat-shock factor.
A. Fortunati, S. Piconese, P. Tassone, S. Ferrari, and F. Migliaccio (2008)
J. Exp. Bot.
   Abstract »    Full Text »    PDF »
Genetic Dissection of Hormonal Responses in the Roots of Arabidopsis Grown under Continuous Mechanical Impedance.
T. Okamoto, S. Tsurumi, K. Shibasaki, Y. Obana, H. Takaji, Y. Oono, and A. Rahman (2008)
Plant Physiology 146, 1651-1662
   Abstract »    Full Text »    PDF »
The Root Cap Determines Ethylene-Dependent Growth and Development in Maize Roots.
A. Hahn, R. Zimmermann, D. Wanke, K. Harter, and H. G. Edelmann (2008)
Mol Plant 1, 359-367
   Abstract »    Full Text »    PDF »
Functional Characterization of PaLAX1, a Putative Auxin Permease, in Heterologous Plant Systems.
K. Hoyerova, L. Perry, P. Hand, M. Lankova, T. Kocabek, S. May, J. Kottova, J. Paces, R. Napier, and E. Zazimalova (2008)
Plant Physiology 146, 1128-1141
   Abstract »    Full Text »    PDF »
Regulation of Root Nitrate Uptake at the NRT2.1 Protein Level in Arabidopsis thaliana.
J. Wirth, F. Chopin, V. Santoni, G. Viennois, P. Tillard, A. Krapp, L. Lejay, F. Daniel-Vedele, and A. Gojon (2007)
J. Biol. Chem. 282, 23541-23552
   Abstract »    Full Text »    PDF »
Ethylene Upregulates Auxin Biosynthesis in Arabidopsis Seedlings to Enhance Inhibition of Root Cell Elongation.
R. Swarup, P. Perry, D. Hagenbeek, D. Van Der Straeten, G. T.S. Beemster, G. Sandberg, R. Bhalerao, K. Ljung, and M. J. Bennett (2007)
PLANT CELL 19, 2186-2196
   Abstract »    Full Text »    PDF »
Subcellular Trafficking of the Arabidopsis Auxin Influx Carrier AUX1 Uses a Novel Pathway Distinct from PIN1.
J. Kleine-Vehn, P. Dhonukshe, R. Swarup, M. Bennett, and J. Friml (2006)
PLANT CELL 18, 3171-3181
   Abstract »    Full Text »    PDF »
Cytokinin-Mediated Cell Cycling Arrest of Pericycle Founder Cells in Lateral Root Initiation of Arabidopsis.
X. Li, X. Mo, H. Shou, and P. Wu (2006)
Plant Cell Physiol. 47, 1112-1123
   Abstract »    Full Text »    PDF »

To Advertise     Find Products

Science Signaling. ISSN 1937-9145 (online), 1945-0877 (print). Pre-2008: Science's STKE. ISSN 1525-8882