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Auxin inhibits endocytosis and promotes its own efflux from cells

Abstract

One of the mechanisms by which signalling molecules regulate cellular behaviour is modulating subcellular protein translocation. This mode of regulation is often based on specialized vesicle trafficking, termed constitutive cycling, which consists of repeated internalization and recycling of proteins to and from the plasma membrane1. No such mechanism of hormone action has been shown in plants although several proteins, including the PIN auxin efflux facilitators, exhibit constitutive cycling2,3. Here we show that a major regulator of plant development, auxin, inhibits endocytosis. This effect is specific to biologically active auxins and requires activity of the Calossin-like protein BIG. By inhibiting the internalization step of PIN constitutive cycling, auxin increases levels of PINs at the plasma membrane. Concomitantly, auxin promotes its own efflux from cells by a vesicle-trafficking-dependent mechanism. Furthermore, asymmetric auxin translocation during gravitropism is correlated with decreased PIN internalization. Our data imply a previously undescribed mode of plant hormone action: by modulating PIN protein trafficking, auxin regulates PIN abundance and activity at the cell surface, providing a mechanism for the feedback regulation of auxin transport.

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Figure 1: Auxins inhibit internalization of constitutively cycling proteins.
Figure 2: Auxin inhibits endocytosis, increases the amount of PIN2 protein at the plasma membrane and stimulates its own efflux from tobacco cells.
Figure 3: BIG protein is required for the auxin-dependent inhibition of endocytosis.
Figure 4: Correlation between auxin translocation and the rate of PIN2 internalization in course of root gravitropism.

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References

  1. Royle, S. & Murrell-Lagnado, R. Constitutive cycling: a general mechanism to regulate cell surface proteins. BioEssays 25, 39–46 (2003)

    Article  PubMed  Google Scholar 

  2. Geldner, N., Friml, J., Stierhof, Y.-D., Jürgens, G. & Palme, K. Auxin transport inhibitors block PIN1 cycling and vesicle trafficking. Nature 413, 425–428 (2001)

    Article  ADS  CAS  PubMed  Google Scholar 

  3. Geldner, N. et al. The Arabidopsis GNOM ARF-GEF mediates endosomal re-cycling, auxin transport, and auxin-dependent plant growth. Cell 112, 219–230 (2003)

    Article  CAS  PubMed  Google Scholar 

  4. Friml, J., Wisniewska, J., Benková, E., Mendgen, K. & Palme, K. Lateral relocation of auxin efflux regulator AtPIN3 mediates tropism in Arabidopsis. Nature 415, 806–809 (2002)

    Article  ADS  PubMed  Google Scholar 

  5. Friml, J. et al. Efflux-dependent auxin gradients establish the apical-basal axis of Arabidopsis. Nature 426, 147–153 (2003)

    Article  ADS  CAS  PubMed  Google Scholar 

  6. Benková, E. et al. Local, efflux-dependent auxin gradients as a common module for plant organ formation. Cell 115, 591–602 (2003)

    Article  PubMed  Google Scholar 

  7. Gray, W. R., Kepinski, S., Rouse, D., Leyser, O. & Estelle, M. Auxin regulates SCFTIR1-dependent degradation of AUX/IAA proteins. Nature 414, 271–276 (2001)

    Article  ADS  CAS  PubMed  Google Scholar 

  8. Friml, J. Auxin transport—shaping the plant. Curr. Opin. Plant Biol. 6, 7–12 (2003)

    Article  CAS  PubMed  Google Scholar 

  9. Baluška, F. et al. F-actin-dependent endocytosis of cell wall pectins in meristematic root cells. Insights from brefeldin A-induced compartments. Plant Physiol. 130, 422–431 (2002)

    Article  PubMed  PubMed Central  Google Scholar 

  10. Von Gadow, A., Joubert, E. & Hansmann, C. F. Comparison of the antioxidant activity of aspalathin with that of other plant phenols of rooibos tea (Aspalathus linearis), alpha-tocopherol, BHT, and BHA. J. Agric. Food Chem. 45, 632–638 (1997)

    Article  CAS  Google Scholar 

  11. Karlin-Neumann, G., Brusslan, J. & Tobin, E. Phytochrome control of the tms2 gene in transgenic Arabidopsis: a strategy for selecting mutants in the signal transduction pathway. Plant Cell 3, 573–582 (1991)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  12. Boerjan, W. et al. Superroot, a recessive mutation in Arabidopsis, confers auxin overproduction. Plant Cell 7, 1405–1419 (1995)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  13. Zhao, Y. et al. A role for flavin monooxygenase-like enzymes in auxin biosynthesis. Science 291, 306–309 (2001)

    Article  ADS  CAS  PubMed  Google Scholar 

  14. Swarup, R. et al. Localisation of the auxin permease AUX1 suggests two functionally distinct hormone transport pathways operate in the Arabidopsis root apex. Genes Dev. 15, 2648–2653 (2001)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  15. Xu, J. & Scheres, B. Dissection of Arabidopsis ADP-RIBOSYLATION FACTOR 1 function in epidermal cell polarity. Plant Cell 17, 525–536 (2005)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  16. Emans, N., Zimmermann, S. & Fischer, R. Uptake of a fluorescent marker in plant cells is sensitive to brefeldin A and wortmannin. Plant Cell 14, 71–86 (2002)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  17. Delbarre, A., Muller, 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 198, 532–541 (1996)

    Article  CAS  PubMed  Google Scholar 

  18. Ruegger, M. et al. Reduced naphthylphthalamic acid binding in the tir3 mutant of Arabidopsis is associated with a reduction in polar auxin transport and diverse morphological defects. Plant Cell 9, 745–757 (1997)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  19. Gil, P. et al. BIG: a calossin-like protein required for polar auxin transport in Arabidopsis. Genes Dev. 15, 1985–1997 (2001)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  20. Kanyuka, K. et al. Mutations in the huge Arabidopsis gene BIG affect a range of hormone and light responses. Plant J. 35, 57–70 (2003)

    Article  CAS  PubMed  Google Scholar 

  21. Berleth, T. & Sachs, T. Plant morphogenesis: long-distance coordination and local patterning. Curr. Opin. Plant Biol. 4, 57–62 (2001)

    Article  CAS  PubMed  Google Scholar 

  22. Morris, D. A. Transmembrane auxin carrier systems—dynamic regulators of polar auxin transport. Plant Growth Regul. 32, 161–172 (2000)

    Article  CAS  PubMed  Google Scholar 

  23. Petrášek, J., Elčkner, M., Morris, D. A. & Zažímalová, E. Auxin efflux carrier activity and auxin accumulation regulate cell division and polarity in tobacco cells. Planta 216, 302–308 (2002)

    Article  PubMed  Google Scholar 

  24. Petrášek, J. et al. Do phytotropins inhibit auxin efflux by impairing vesicle traffic? Plant Physiol. 131, 254–263 (2003)

    Article  PubMed  PubMed Central  Google Scholar 

  25. Delarue, M., Muller, P., Bellini, C. & Delbarre, A. Increased auxin efflux in the IAA-overproducing sur1 mutant of Arabidopsis thaliana: a mechanism of reducing auxin levels? Physiol. Plant. 107, 120–127 (1999)

    Article  CAS  Google Scholar 

  26. Richards, S., Hillman, T. & Stern, M. Mutations in the Drosophila pushover gene confer increased neuronal excitability and spontaneous synaptic vesicle fusion. Genetics 142, 1215–1223 (1996)

    CAS  PubMed  PubMed Central  Google Scholar 

  27. Cutler, S., Ehrhardt, D., Griffitts, J. & Somerville, C. Random GFP::cDNA fusions enable visualisation of subcellular structures in cells of Arabidopsis at a high frequency. Proc. Natl Acad. Sci. USA 97, 3718–3723 (2000)

    Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

  28. Friml, J., Benková, E., Mayer, U., Palme, K. & Muster, G. Automated whole-mount localization techniques for plant seedlings. Plant J. 34, 115–124 (2003)

    Article  CAS  PubMed  Google Scholar 

  29. Friml, J. et al. AtPIN4 mediates sink-driven auxin gradients and root patterning in Arabidopsis. Cell 108, 661–673 (2002)

    Article  CAS  PubMed  Google Scholar 

  30. Pimpl, P. et al. In situ localization and in vitro induction of plant COPI -coated vesicles. Plant Cell 12, 2219–2236 (2000)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

Download references

Acknowledgements

We thank C. Bellini, M. Bennett, M. Estelle, M. Grebe, W. Michalke, D. Robinson and Y. Zhao for sharing material, and E. Benková, P. Brewer, J. Eder, J. Malbeck, C. Oecking, M. Sauer, H. Stransky and D. Weijers for technical assistance and discussions. This work was supported by the Volkswagenstiftung (J.F. and T.P.), the F. Ebert Stiftung (J.K.-V.), the Deutsche Forschungsgemeinschaft (N.G., G.J. and Y.-D. S.), the Grant Agency of the Academy of Sciences of the Czech Republic (J.P. and E.Z.) and the Royal Society of London (D.A.M.).

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Correspondence to Jir̆í Friml.

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Reprints and permissions information is available at npg.nature.com/reprintsandpermissions. The authors declare no competing financial interests.

Supplementary information

Supplementary Figure S1

Auxins inhibit BFA-induced internalisation of constitutively cycling PM markers. (JPG 337 kb)

Supplementary Figure S2

Inhibitors of protein expression and degradation confirm BFA-visualized constitutive cycling of PIN1. (JPG 66 kb)

Supplementary Figure S3

Other plant hormones do not inhibit internalisation of constitutively cycling proteins. (JPG 109 kb)

Supplementary Figure S4

5 µM concentrations of NAA and 2,4-D inhibit BFA-induced internalisation of constitutively cycling proteins. (JPG 336 kb)

Supplementary Figure S5

IAA is unstable in Arabidopsis medium but, if stabilised, it inhibits BFA-induced internalisation at 5 µM concentrations. (JPG 178 kb)

Supplementary Figure S6

Auxins down-regulate but do not completely block BFA-induced internalisation of constitutively cycling proteins. (JPG 127 kb)

Supplementary Figure S7

NAA does not influence BFA uptake in Arabidopsis root tissues. (JPG 73 kb)

Supplementary Figure S8

Auxins do not affect the morphology of selected subcellular structures. (JPG 146 kb)

Supplementary Figure S9

Auxins inhibit the BFA-induced internalisation of PM proteins but do not affect BFA-induced aggregation of endosomes. (JPG 160 kb)

Supplementary Figure S10

Auxin efflux in suspension-cultured BY-2 and VBI-0 tobacco cells. (JPG 72 kb)

Supplementary data legends (DOC 38 kb)

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Paciorek, T., Zažímalová, E., Ruthardt, N. et al. Auxin inhibits endocytosis and promotes its own efflux from cells. Nature 435, 1251–1256 (2005). https://doi.org/10.1038/nature03633

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