Auxin efflux by PIN-FORMED proteins is activated by two different protein kinases, D6 PROTEIN KINASE and PINOID
- Technische Universität München, Germany
- Universität Regensburg, Germany
- Salk Institute for Biological Studies, United States
- Göttingen University Medical Center, Germany
- Université Evry, France
- Syngenta Seeds B.V, Netherlands
- King Abdullah University of Science and Technology, Saudi Arabia
- Max-Planck-Institute of Molecular Plant Physiology, Germany
Abstract
The development and morphology of vascular plants is critically determined by synthesis and proper distribution of the phytohormone auxin. The directed cell-to-cell distribution of auxin is achieved through a system of auxin influx and efflux transporters. PIN-FORMED (PIN) proteins are proposed auxin efflux transporters, and auxin fluxes can seemingly be predicted based on the - in many cells - asymmetric plasma membrane distribution of PINs. Here, we show in a heterologous Xenopus oocyte system as well as in Arabidopsis thaliana inflorescence stems that PIN-mediated auxin transport is directly activated by D6 PROTEIN KINASE (D6PK) and PINOID (PID)/WAG kinases of the Arabidopsis AGCVIII kinase family. At the same time, we reveal that D6PKs and PID have differential phosphosite preferences. Our study suggests that PIN activation by protein kinases is a crucial component of auxin transport control that must be taken into account to understand auxin distribution within the plant.
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Animal experimentation: This study was performed in strict accordance with the recommendations and guidelines based on the Tierschutzgesetz (TierSchG) of the Federal Republic of Germany.
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© 2014, Zourelidou et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Auxin efflux by PIN-FORMED proteins is activated by two different protein kinases, D6 PROTEIN KINASE and PINOID
eLife 3:e02860.
https://doi.org/10.7554/eLife.02860
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