Structures and mechanism of the plant PIN-FORMED auxin transporter

Kien Lam Ung, Mikael Winkler, Lukas Schulz, Martina Kolb, Dorina P. Janacek, Emil Dedic, David L. Stokes, Ulrich Z. Hammes () and Bjørn Panyella Pedersen ()
Additional contact information
Kien Lam Ung: Aarhus University
Mikael Winkler: Aarhus University
Lukas Schulz: Technical University of Munich
Martina Kolb: Technical University of Munich
Dorina P. Janacek: Technical University of Munich
Emil Dedic: Aarhus University
David L. Stokes: New York University School of Medicine
Ulrich Z. Hammes: Technical University of Munich
Bjørn Panyella Pedersen: Aarhus University

Nature, 2022, vol. 609, issue 7927, 605-610

Abstract: Abstract Auxins are hormones that have central roles and control nearly all aspects of growth and development in plants1–3. The proteins in the PIN-FORMED (PIN) family (also known as the auxin efflux carrier family) are key participants in this process and control auxin export from the cytosol to the extracellular space4–9. Owing to a lack of structural and biochemical data, the molecular mechanism of PIN-mediated auxin transport is not understood. Here we present biophysical analysis together with three structures of Arabidopsis thaliana PIN8: two outward-facing conformations with and without auxin, and one inward-facing conformation bound to the herbicide naphthylphthalamic acid. The structure forms a homodimer, with each monomer divided into a transport and scaffold domain with a clearly defined auxin binding site. Next to the binding site, a proline–proline crossover is a pivot point for structural changes associated with transport, which we show to be independent of proton and ion gradients and probably driven by the negative charge of the auxin. The structures and biochemical data reveal an elevator-type transport mechanism reminiscent of bile acid/sodium symporters, bicarbonate/sodium symporters and sodium/proton antiporters. Our results provide a comprehensive molecular model for auxin recognition and transport by PINs, link and expand on a well-known conceptual framework for transport, and explain a central mechanism of polar auxin transport, a core feature of plant physiology, growth and development.

Date: 2022
References: Add references at CitEc
Citations: View citations in EconPapers (3)

Downloads: (external link)
https://www.nature.com/articles/s41586-022-04883-y Abstract (text/html)
Access to the full text of the articles in this series is restricted.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:nature:v:609:y:2022:i:7927:d:10.1038_s41586-022-04883-y

Ordering information: This journal article can be ordered from
https://www.nature.com/

DOI: 10.1038/s41586-022-04883-y

Access Statistics for this article

Nature is currently edited by Magdalena Skipper

More articles in Nature from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().