Structures and mechanisms of the Arabidopsis cytokinin transporter AZG1.
Nat Plants
; 10(1): 180-191, 2024 01.
Article
em En
| MEDLINE
| ID: mdl-38172575
ABSTRACT
Cytokinins are essential for plant growth and development, and their tissue distributions are regulated by transmembrane transport. Recent studies have revealed that members of the 'Aza-Guanine Resistant' (AZG) protein family from Arabidopsis thaliana can mediate cytokinin uptake in roots. Here we present 2.7 to 3.3 Å cryo-electron microscopy structures of Arabidopsis AZG1 in the apo state and in complex with its substrates trans-zeatin (tZ), 6-benzyleaminopurine (6-BAP) or kinetin. AZG1 forms a homodimer and each subunit shares a similar topology and domain arrangement with the proteins of the nucleobase/ascorbate transporter (NAT) family. These structures, along with functional analyses, reveal the molecular basis for cytokinin recognition. Comparison of the AZG1 structures determined in inward-facing conformations and predicted by AlphaFold2 in the occluded conformation allowed us to propose that AZG1 may carry cytokinins across the membrane through an elevator mechanism.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Arabidopsis
/
Proteínas de Arabidopsis
Idioma:
En
Ano de publicação:
2024
Tipo de documento:
Article
País de afiliação:
China