Database of articles cited by EMDB/PDB/SASBDB data

Keywords
Structure methods	All X-ray diffraction NMR electron microscopy small angle scattering neutron diffraction fiber diffraction powder diffraction infrared spectroscopy EPR fluorescence transfer theoretical model Hybrid
Author
Journal
IF	>30 >20 >10 >5 all

Title	Structures and mechanism of the AUX/LAX transporters involved in auxin import.
Journal, issue, pages	Nat Plants, Vol. 11, Issue 8, Page 1670-1680, Year 2025
Publish date	Aug 4, 2025
Authors	Kien Lam Ung / Lukas Schulz / Lorena Zuzic / Bjørn Lildal Amsinck / Sarah Koutnik-Abele / Ines Benhammouche / Camilla Gottlieb Andersen / Lynette Nel / Birgit Schiøtt / David L Stokes / Ulrich Zeno Hammes / Bjørn Panyella Pedersen /
PubMed Abstract	Auxins are plant hormones that direct the growth and development of organisms on the basis of environmental cues. Indole-3-acetic acid (IAA) is the most abundant auxin in most plants. A variety of ...Auxins are plant hormones that direct the growth and development of organisms on the basis of environmental cues. Indole-3-acetic acid (IAA) is the most abundant auxin in most plants. A variety of membrane transport proteins work together to distribute auxins. These include the AUX/LAX protein family that mediate auxin import from the apoplast to the cytosol. Here we use structural and biophysical approaches combined with molecular dynamics to study transport by Arabidopsis thaliana LAX3, which is essential for plant root formation. Transport assays document high-affinity transport of IAA, as well as competitive behaviour of the synthetic phenoxyacetic acid auxin herbicide 2,4-dichlorophenoxyacetic acid and the auxin transport inhibitors 1-naphthoxyacetic acid and 2-naphthoxyacetic acid. Four cryo-EM structures were solved with resolutions of 2.9-3.4 Å: an inward open apo structure, two inward semi-occluded structures in complex with IAA and 2,4-dichlorophenoxyacetic acid, and a fully occluded structure in complex with 2-naphthoxyacetic acid. Structurally, LAX3 consists of a bundle and a scaffold domain. The ligand-binding site is sandwiched between these domains with two histidines occupying positions analogous to the sodium-binding sites in distantly related sodium:neurotransmitter transporters. This architecture suggests that these histidines couple transport to the proton motive force. Molecular dynamics simulations are used to explore substrate binding and release, including their dependence on specific protonation states. This study advances our understanding of auxin recognition and transport by AUX/LAX, providing insights into a fundamental aspect of plant physiology and development.
External links	Nat Plants / PubMed:40759769 / PubMed Central
Methods	EM (single particle)
Resolution	2.88 - 3.43 Å
Structure data	51894 9h61 EMDB-51894, PDB-9h61: Auxin transporter-like protein 3 (LAX3) in the inward occluded state in complex with auxin (Indole-3-acetic acid, IAA) Method: EM (single particle) / Resolution: 3.21 Å 51895 9h62 EMDB-51895, PDB-9h62: Auxin transporter-like protein 3 (LAX3) in the inward occluded state in complex with 2,4-Dichlorophenoxyacetic acid (2,4-D) Method: EM (single particle) / Resolution: 3.43 Å 51896 9h63 EMDB-51896, PDB-9h63: Auxin transporter-like protein 3 (LAX3) in the fully occluded state in complex with 2-naphthoxyacetic acid (2-NOA) Method: EM (single particle) / Resolution: 2.88 Å 53308 9qqm EMDB-53308, PDB-9qqm: Auxin transporter-like protein 3 (LAX3) in the inward open state, apo Method: EM (single particle) / Resolution: 3.16 Å
Chemicals	ChemComp-IAC: 1H-INDOL-3-YLACETIC ACID / hormoneYM ChemComp-HOH: WATER ChemComp-CFA: (2,4-DICHLOROPHENOXY)ACETIC ACID PDB-1isn*: Crystal structure of merlin FERM domain
Source	arabidopsis thaliana (thale cress)
Keywords	MEMBRANE PROTEIN / Auxin transmembrane transport / AAAP family / APC superfamily / TRANSPORT PROTEIN