The phytohormone auxin is transported through the plant body either via vascular pathways or from cell to cell by specialized polar transport machinery. This machinery consists of a balanced system of passive diffusion combined with the activities of auxin influx and efflux carriers. Synthetic auxins that differ in the mechanisms of their transport across the plasma membrane together with polar auxin transport inhibitors have been used in many studies on particular auxin carriers and their role in plant development. However, the exact mechanism of action of auxin efflux and influx inhibitors has not been fully elucidated. In this report, the mechanism of action of the auxin influx inhibitors (1-naphthoxyacetic acid (1-NOA), 2-naphthoxyacetic acid (2-NOA), and 3-chloro-4-hydroxyphenylacetic acid (CHPAA)) is examined by direct measurements of auxin accumulation, cellular phenotypic analysis, as well as by localization studies of Arabidopsis thaliana L. auxin carriers heterologously expressed in Nicotiana tabacum L., cv. Bright Yellow cell suspensions. The mode of action of 1-NOA, 2-NOA, and CHPAA has been shown to be linked with the dynamics of the plasma membrane. The most potent inhibitor, 1-NOA, blocked the activities of both auxin influx and efflux carriers, whereas 2-NOA and CHPAA at the same concentration preferentially inhibited auxin influx. The results suggest that these, previously unknown, activities of putative auxin influx inhibitors regulate overall auxin transport across the plasma membrane depending on the dynamics of particular membrane vesicles.

Institute of Experimental Botany Academy of Sciences of the Czech Republic Rozvojová 263 CZ 165 02 Prague 6 Czech Republic

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An G. High efficiency transformation of cultured tobacco cells. Plant Physiology. 1985;79:568–570. PubMed PMC

Bainbridge K, Guyomarc'h S, Bayer E, Swarup R, Bennett M, Mandel T, Kuhlemeier C. Auxin influx carriers stabilize phyllotactic patterning. Genes and Development. 2008;22:810–823. PubMed PMC

Benková E, Michniewicz M, Sauer M, Teichmann T, Seifertová D, Jürgens G, Friml J. Local, efflux-dependent auxin gradients as a common module for plant organ formation. Cell. 2003;115:591–602. PubMed

Bennett MJ, Marchant A, Green HG, May ST, Ward SP, Millner PA, Walker AR, Schulz B, Feldmann KA. Arabidopsis AUX1 gene: a permease-like regulator of root gravitropism. Science. 1996;273:948–950. PubMed

Blilou I, Xu J, Wildwater M, Willemsen V, Paponov I, Friml J, Heidstra R, Aida M, Palme K, Scheres B. The PIN auxin efflux facilitator network controls growth and patterning in Arabidopsis roots. Nature. 2005;433:39–44. PubMed

Borner GHH, Sherrier DJ, Weimar T, Michaelson LV, Hawkins ND, MacAskill A, Napier JA, Beale MH, Lilley KS, Dupree P. Analysis of detergent-resistant membranes in Arabidopsis. Evidence for plasma membrane lipid rafts. Plant Physiology. 2005;137:104–116. PubMed PMC

Curtis MD, Grossniklaus U. A gateway cloning vector set for high-throughput functional analysis of genes in planta. Plant Physiology. 2003;133:462–469. PubMed PMC

Delbarre A, Müller P, Imhoff V, Guern J. Comparison of mechanisms controlling uptake and accumulation of 2,4-dichlorophenoxy acetic acid, naphthalene-1-acetic acid, and indole-3-acetic acid in suspension-cultured tobacco cells. Planta. 1996;198:532–541. PubMed

Dhonukshe P, Baluška F, Schlicht M, Hlavacka A, Šamaj J, Friml J, Gadella T. Endocytosis of cell surface material mediates cell plate formation during plant cytokinesis. Developmental Cell. 2006;10:137–150. PubMed

Dhonukshe P, Grigoriev I, Fischer R, et al. Auxin transport inhibitors impair vesicle motility and actin cytoskeleton dynamics in diverse eukaryotes. Proceedings of the National Academy of Sciences, USA. 2008;105:4489–4494. PubMed PMC

Dhonukshe P, Mathur J, Hülskamp M, Gadella TW. Microtubule plus-ends reveal essential links between intracellular polarization and localized modulation of endocytosis during division-plane establishment in plant cells. BMC Biology. 2005;3:11. PubMed PMC

Edgerton MD, Tropsha A, Jones AM. Modelling the auxin-binding site of auxin-binding protein 1 of maize. Phytochemistry. 1994;35:1111–1123.

Friml J, Benkova E, Blilou I, et al. AtPIN4 mediates sink-driven auxin gradients and root patterning in Arabidopsis. Cell. 2002b;108:661–673. PubMed

Friml J, Wisniewska J, Benková E, Mendgen K, Palme K. Lateral relocation of auxin efflux regulator PIN3 mediates tropism in Arabidopsis. Nature. 2002a;415:806–809. PubMed

Friml J. Auxin transport: shaping the plant. Current Opinion in Plant Biology. 2003;6:7–12. PubMed

Geldner N, Friml J, Stierhof YD, Jürgens G, Palme K. Auxin transport inhibitors block PIN1 cycling and vesicle trafficking. Nature. 2001;413:425–428. PubMed

Imhoff V, Muller P, Guern J, Delbarre A. Inhibitors of the carrier-mediated influx of auxin in suspension-cultured tobacco cells. Planta. 2000;210:580–588. PubMed

Jelínková A, Malínská K, Simon S, et al. Probing plant membranes with FM dyes: tracking, dragging or blocking? The Plant Journal. 2010;61:883–892. PubMed

Jones AR, Kramer EM, Knox K, Swarup R, Bennett MJ, Lazarus CM, Leyser HMO, Grierson CS. Auxin transport through non-hair cells sustains root-hair development. Nature Cell Biology. 2009;11:78–84. PubMed PMC

Kleine-Vehn J, Dhonukshe P, Swarup R, Bennett M, Friml J. Subcellular trafficking of the Arabidopsis auxin influx carrier AUX1 uses a novel pathway distinct from PIN1. The Plant Cell. 2006;18:3171–3181. PubMed PMC

Lomax TL, Muday GK, Rubery PH. Auxin transport. In: Davies PJ, editor. Plant hormones: physiology, biochemistry and molecular biology. Dordrecht, Netherlands: Kluwer; 1995. pp. 509–530.

Maisch J, Nick P. Actin is involved in auxin-dependent patterning. Plant Physiology. 2007;143:1695–1704. PubMed PMC

Marchant A, Bhalerao R, Casimiro I, Eklöf J, Casero PJ, Bennett M, Sandberg G. AUX1 promotes lateral root formation by facilitating indole-3-acetic acid distribution between sink and source tissues in the Arabidopsis seedling. The Plant Cell. 2002;14:589–597. PubMed PMC

Morris DA, Robinson JS. Targeting of auxin carriers to the plasma membrane: differential effects of brefeldin A on the traffic of auxin uptake and efflux carriers. Planta. 1998;205:606–612.

Morris DA, Friml J, Zažímalová E. The transport of auxins. In: Davies PJ, editor. Plant hormones: biosynthesis, signal transduction, action! Dordrecht, Boston, London: Kluwer Academic Publishers; 2004. pp. 437–470.

Nagata T, Nemoto Y, Hasezava S. Tobacco BY-2 cell line as the ‘Hela’ cell in the cell biology of higher plants. International Review of Cytology. 1992;132:1–30.

Nick P, Han M, An G. Auxin stimulates its own transport by shaping actin filaments. Plant Physiology. 2009;151:155–167. PubMed PMC

Noh B, Murphy AS, Spalding EP. Multidrug resistance-like genes of Arabidopsis required for auxin transport and auxin-mediated development. The Plant Cell. 2001;13:2441–2454. PubMed PMC

Parry G, Delbarre A, Marchant A, Swarup R, Napier R, Perrot-Rechenmann C, Bennett MJ. Novel auxin transport inhibitors phenocopy the auxin influx carrier mutation aux1. The Plant Journal. 2001;25:399–406. PubMed

Pernisová M, Klíma P, Horák J, et al. Cytokinins modulate auxin-induced organogenesis in plants via regulation of the auxin efflux. Proceedings of the National Academy of Sciences, USA. 2009;106:3609–3614. PubMed PMC

Petrášek J, Elčkner M, Morris DA, Zažímalová E. Auxin efflux carrier activity and auxin accumulation regulate cell division and polarity in tobacco cells. Planta. 2002;216:302–308. PubMed

Petrášek J, Černá A, Schwarzerová K, Elčkner M, Morris DA, Zažímalová E. Do phytotropins inhibit auxin efflux by impairing vesicle traffic? Plant Physiology. 2003;131:254–263. PubMed PMC

Petrášek J, Mravec J, Bouchard R, et al. PIN proteins perform a rate-limiting function in cellular auxin efflux. Science. 2006;312:914–918. PubMed

Petrášek J, Zažímalová E. The BY-2 cell line as a tool to study auxin transport. In: Nagata T, Matsuoka K, Inzé D, editors. Biotechnology in agriculture and forestry 58, Tobacco BY-2 cells: from cellular dynamics to omics. Berlin, Heidelberg: Springer-Verlag; 2006. pp. 107–117.

Rahman A, Ahamed A, Amakawa T, Goto N, Tsurumi S. Chromosaponin I specifically interacts with AUX1 protein in regulating the gravitropic response of arabidopsis roots. Plant Physiology. 2001;125:990–1000. PubMed PMC

Rubery PH. Phytotropins: receptors and endogenous ligands. Symposia of the Society for Experimental Biology. 1990;44:119–146. PubMed

Smith RS, Guyomarc'h S, Mandel T, Reinhardt D, Kuhlemeier C, Prusinkiewicz P. A plausible model for phyllotaxis. Proceedings of the National Academy of Sciences, USA. 2006;103:1301–1306. PubMed PMC

Souter M, Topping J, Pullen M, Friml J, Palme K, Hackett R, Grierson D, Lindsey K. hydra mutants of Arabidopsis are defective in sterol profiles and auxin and ethylene signaling. The Plant Cell. 2002;14:1017–1031. PubMed PMC

Swarup R, Friml J, Marchant A, Ljung K, Sandberg G, Palme G, Bennett MJ. Localization of the auxin permease AUX1 suggests two functionally distinct hormone transport pathways operate in the Arabidopsis root apex. Genes and Development. 2001;15:2648–2653. PubMed PMC

Swarup K, Benková E, Swarup R, et al. The auxin influx carrier LAX3 promotes lateral root emergence. Nature Cell Biology. 2008;10:946–954. PubMed

Titapiwatanakun B, Murphy AS. Post-transcriptional regulation of auxin transport proteins: cellular trafficking, protein phosphorylation, protein maturation, ubiquitination, and membrane composition. Journal of Experimental Botany. 2009;60:1093–1097. PubMed

Ugartechea-Chirino Y, Swarup R, Swarup K, Péret B, Whitworth M, Bennett M, Bougourd S. The AUX1 LAX family of auxin influx carriers is required for the establishment of embryonic root cell organization in Arabidopsis thaliana. Annals of Botany. 2010;105:277–289. PubMed PMC

Vandenbussche F, Petrášek J, Žádníková P, et al. The auxin influx carriers AUX1 and LAX3 are involved in auxin-ethylene interactions during apical hook development in Arabidopsis thaliana seedlings. Development. 2010;137:597–606. PubMed

Vanneste S, Friml J. Auxin: a trigger for change in plant development. Cell. 2009;136:1005–1016. PubMed

Vieten A, Sauer M, Brewer PB, Friml J. Molecular and cellular aspects of auxin-transport-mediated development. Trends in Plant Science. 2007;12:160–168. PubMed

Wilkinson S, Morris DA. Targeting of auxin carriers to the plasma membrane: effects of monensin on transmembrane auxin transport in Cucurbita pepo L. tissue. Planta. 1994;193:194–202.

Yang Y, Hammes UZ, Taylor CG, Schachtman DP, Nielsen E. High-affinity auxin transport by the AUX1 influx carrier protein. Current Biology. 2006;16:1123–1127. PubMed

Zažímalová E, Opatrný Z, Březinová A, Eder J. The effect of auxin starvation on the growth of auxin-dependent tobacco cell culture: dynamics of auxin reception and endogenous free IAA content. Journal of Experimental Botany. 1995;46:1205–1213.

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