Arabidopsis WAT1 is a vacuolar auxin transport facilitator required for auxin homoeostasis

0421943 - ÚEB 2014 RIV GB eng J - Journal Article
Ranocha, P. - Dima, O. - Nagy, R. - Novák, Ondřej - Goffner, D. … Total 18 authors
Arabidopsis WAT1 is a vacuolar auxin transport facilitator required for auxin homoeostasis.
Nature Communications. Roč. 4, č. 2013 (2013). E-ISSN 2041-1723
R&D Projects: GA MŠMT LK21306
Institutional research plan: CEZ:AV0Z50380511
Keywords : BINDING PROTEIN-1 * POLAR TRANSPORT * PLANTS
Subject RIV: EF - Botanics
Impact factor: 10.742, year: 2013

The plant hormone auxin (indole-3-acetic acid, IAA) has a crucial role in plant development. Its spatiotemporal distribution is controlled by a combination of biosynthetic, metabolic and transport mechanisms. Four families of auxin transporters have been identified that mediate transport across the plasma or endoplasmic reticulum membrane. Here we report the discovery and the functional characterization of the first vacuolar auxin transporter. We demonstrate that WALLS ARE THIN1 (WAT1), a plant-specific protein that dictates secondary cell wall thickness of wood fibres, facilitates auxin export from isolated Arabidopsis vacuoles in yeast and in Xenopus oocytes. We unambiguously identify IAA and related metabolites in isolated Arabidopsis vacuoles, suggesting a key role for the vacuole in intracellular auxin homoeostasis. Moreover, local auxin application onto wat1 mutant stems restores fibre cell wall thickness. Our study provides new insight into the complexity of auxin transport in plants and a means to dissect auxin function during fibre differentiation.
Permanent Link: http://hdl.handle.net/11104/0228211