Structure and function of the <i>Arabidopsis</i> ABC transporter ABCB19 in brassinosteroid export

2024/03/21 by Wei Ying, Yaowei Wang, Hong Wei +13 · 2 voices · 4 citations
Agricultural and Biological Sciences · Biochemistry, Genetics and Molecular Biology · #Plant Molecular Biology Research #Photosynthetic Processes and Mechanisms #Plant Stress Responses and Tolerance

paper · doi:10.1126/science.adj4591

openalex publication_date 2024/03/21 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31

Abstract

Brassinosteroids are steroidal phytohormones that regulate plant development and physiology, including adaptation to environmental stresses. Brassinosteroids are synthesized in the cell interior but bind receptors at the cell surface, necessitating a yet to be identified export mechanism. Here, we show that a member of the ATP-binding cassette (ABC) transporter superfamily, ABCB19, functions as a brassinosteroid exporter. We present its structure in both the substrate-unbound and the brassinosteroid-bound states. Bioactive brassinosteroids are potent activators of ABCB19 ATP hydrolysis activity, and transport assays showed that ABCB19 transports brassinosteroids. In Arabidopsis thaliana , ABCB19 and its close homolog, ABCB1, positively regulate brassinosteroid responses. Our results uncover an elusive export mechanism for bioactive brassinosteroids that is tightly coordinated with brassinosteroid signaling.

Citations

• Floral dip: a simplified method for Agrobacterium ‐mediated transformation of Arabidopsis thaliana
• A Brassinosteroid-Insensitive Mutant in Arabidopsis thaliana Exhibits Multiple Defects in Growth and Development
• <scp>UCSF ChimeraX</scp>: Structure visualization for researchers, educators, and developers
• Highly accurate protein structure prediction with AlphaFold

Cited by

• The ABC transporter SmABCG1 mediates tanshinones export from the peridermic cells of <i>Salvia miltiorrhiza</i> root
• The deubiquitinase UBP15 and the E3 ubiquitin ligase PUB17 coordinate GLK1 stability in apple anthocyanin deposition
• Understanding brassinosteroid‐centric phytohormone interactions for crop improvement
• Tailored for swift recognition: A structural perspective on secondary active plant hormone transporters

Discussions

• Structural and functional analysis of ABCB19 demonstrates its role as a brassinosteroid transporter Paper: doi.org/10.1126/science.adj4591 (15/34) [bsky, 1 points, 1 comments]
• Structure and function of the ABC transporter ABCB19 in brassinosteroid export. Science Check the #cryoEM #structure this #membrane #ABC #transporter #protein in the UniTmp database: https://pdbtm.un [bsky, 0 points, 0 comments]

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