EMD-33692
Structure of the auxin exporter PIN1 in Arabidopsis thaliana in the NPA-bound state
EMD-33692
Single-particle3.3 Å
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Map released: 07/09/2022
Last modified: 06/11/2024
Sample Organism:
Arabidopsis thaliana,
Escherichia coli
Sample: AtPIN1 in complex with a nanobody and NPA
Fitted models: 7y9u (Avg. Q-score: 0.492)
Deposition Authors: Sun L
,
Liu X
,
Yang Z,
Xia J
Sample: AtPIN1 in complex with a nanobody and NPA
Fitted models: 7y9u (Avg. Q-score: 0.492)
Deposition Authors: Sun L
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Structural insights into auxin recognition and efflux by Arabidopsis PIN1.
Yang Z,
Xia J,
Hong J,
Zhang C,
Wei H
,
Ying W,
Sun C,
Sun L
,
Mao Y,
Gao Y,
Tan S
,
Friml J
,
Li D
,
Liu X
,
Sun L
(2022) Nature , 609 , 611 - 615
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(2022) Nature , 609 , 611 - 615
Abstract:
Polar auxin transport is unique to plants and coordinates their growth and development1,2. The PIN-FORMED (PIN) auxin transporters exhibit highly asymmetrical localizations at the plasma membrane and drive polar auxin transport3,4; however, their structures and transport mechanisms remain largely unknown. Here, we report three inward-facing conformation structures of Arabidopsis thaliana PIN1: the apo state, bound to the natural auxin indole-3-acetic acid (IAA), and in complex with the polar auxin transport inhibitor N-1-naphthylphthalamic acid (NPA). The transmembrane domain of PIN1 shares a conserved NhaA fold5. In the substrate-bound structure, IAA is coordinated by both hydrophobic stacking and hydrogen bonding. NPA competes with IAA for the same site at the intracellular pocket, but with a much higher affinity. These findings inform our understanding of the substrate recognition and transport mechanisms of PINs and set up a framework for future research on directional auxin transport, one of the most crucial processes underlying plant development.
Polar auxin transport is unique to plants and coordinates their growth and development1,2. The PIN-FORMED (PIN) auxin transporters exhibit highly asymmetrical localizations at the plasma membrane and drive polar auxin transport3,4; however, their structures and transport mechanisms remain largely unknown. Here, we report three inward-facing conformation structures of Arabidopsis thaliana PIN1: the apo state, bound to the natural auxin indole-3-acetic acid (IAA), and in complex with the polar auxin transport inhibitor N-1-naphthylphthalamic acid (NPA). The transmembrane domain of PIN1 shares a conserved NhaA fold5. In the substrate-bound structure, IAA is coordinated by both hydrophobic stacking and hydrogen bonding. NPA competes with IAA for the same site at the intracellular pocket, but with a much higher affinity. These findings inform our understanding of the substrate recognition and transport mechanisms of PINs and set up a framework for future research on directional auxin transport, one of the most crucial processes underlying plant development.