Arabidopsis TWISTED DWARF1 functionally interacts with Auxin Exporter ABCB1 on the root plasma membrane

TY - JOUR

T1 - Arabidopsis TWISTED DWARF1 functionally interacts with Auxin Exporter ABCB1 on the root plasma membrane

AU - Wang, Bangjun

AU - Bailly, Aurélien

AU - Zwiewka, Marta

AU - Henrichs, Sina

AU - Azzarello, Elisa

AU - Mancuso, Stefano

AU - Maeshima, Masayoshi

AU - Friml, Jirí

AU - Schulz, Alexander

AU - Geisler, Markus

PY - 2013

Y1 - 2013

N2 - Plant architecture is influenced by the polar, cell-to-cell transport of auxin that is primarily provided and regulated by plasma membrane efflux catalysts of the PIN-FORMED and B family of ABC transporter (ABCB) classes. The latter were shown to require the functionality of the FK506 binding protein42 TWISTED DWARF1 (TWD1), although underlying mechanisms are unclear. By genetic manipulation of TWD1 expression, we show here that TWD1 affects shootward root auxin reflux and, thus, downstream developmental traits, such as epidermal twisting and gravitropism of the root. Using immunological assays, we demonstrate a predominant lateral, mainly outward-facing, plasma membrane location for TWD1 in the root epidermis characterized by the lateral marker ABC transporter G36/PLEIOTROPIC DRUG-RESISTANCE8/PENETRATION3. At these epidermal plasma membrane domains, TWD1 colocalizes with nonpolar ABCB1. In planta bioluminescence resonance energy transfer analysis was used to verify specific ABC transporter B1 (ABCB1)-TWD1 interaction. Our data support a model in which TWD1 promotes lateral ABCB-mediated auxin efflux via protein-protein interaction at the plasma membrane, minimizing reflux from the root apoplast into the cytoplasm.

AB - Plant architecture is influenced by the polar, cell-to-cell transport of auxin that is primarily provided and regulated by plasma membrane efflux catalysts of the PIN-FORMED and B family of ABC transporter (ABCB) classes. The latter were shown to require the functionality of the FK506 binding protein42 TWISTED DWARF1 (TWD1), although underlying mechanisms are unclear. By genetic manipulation of TWD1 expression, we show here that TWD1 affects shootward root auxin reflux and, thus, downstream developmental traits, such as epidermal twisting and gravitropism of the root. Using immunological assays, we demonstrate a predominant lateral, mainly outward-facing, plasma membrane location for TWD1 in the root epidermis characterized by the lateral marker ABC transporter G36/PLEIOTROPIC DRUG-RESISTANCE8/PENETRATION3. At these epidermal plasma membrane domains, TWD1 colocalizes with nonpolar ABCB1. In planta bioluminescence resonance energy transfer analysis was used to verify specific ABC transporter B1 (ABCB1)-TWD1 interaction. Our data support a model in which TWD1 promotes lateral ABCB-mediated auxin efflux via protein-protein interaction at the plasma membrane, minimizing reflux from the root apoplast into the cytoplasm.

KW - binding cassette transporter

KW - cells

KW - efflux

KW - immunophilin

KW - lateral root

KW - localization

KW - p-glycoproteins

KW - pin

KW - plant development

KW - resistance

U2 - 10.1105/tpc.112.105999

DO - 10.1105/tpc.112.105999

M3 - Journal article

C2 - 23321285

SN - 1040-4651

VL - 25

SP - 202

EP - 214

JO - Plant Cell

JF - Plant Cell

IS - 1

ER -