Substrate Recognition and Transport Mechanism of the PIN-FORMED Auxin Exporters

Overview

Journal Trends Biochem Sci

Specialty Biochemistry

Date 2023 Aug 13

PMID 37574372

Authors

Kien Lam Ung

Lukas Schulz

David L Stokes

Ulrich Z Hammes

Bjorn Panyella Pedersen

Affiliations

Soon will be listed here.

Abstract

Auxins are pivotal plant hormones that regulate plant growth and transmembrane polar auxin transport (PAT) direct patterns of development. The PIN-FORMED (PIN) family of membrane transporters mediate auxin export from the plant cell and play crucial roles in PAT. Here we describe the recently solved structures of PIN transporters, PIN1, PIN3, and PIN8, and also their mechanisms of substrate recognition and transport of auxin. We compare structures of PINs in both inward- and outward-facing conformations, as well as PINs with different binding configurations for auxin. By this comparative analysis, a model emerges for an elevator transport mechanism. Central structural elements necessary for function are identified, and we show that these are shared with other distantly related protein families.

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