1. ABC transporter OsABCG18 controls the shootward transport of cytokinins and grain yield in rice
- Author
-
Kewei Zhang, Jiangzhe Zhao, Engao Zhu, Zhang Yanjun, Mengyuan Zhang, Biao Fan, Min Ju, and Ningning Yu
- Subjects
0106 biological sciences ,0301 basic medicine ,Cytokinins ,Physiology ,long-distance translocation ,Green Fluorescent Proteins ,Nicotiana benthamiana ,ATP-binding cassette transporter ,Plant Science ,efflux transporter ,01 natural sciences ,Plant Roots ,03 medical and health sciences ,chemistry.chemical_compound ,cytokinin ,Gene Expression Regulation, Plant ,heterocyclic compounds ,Vascular tissue ,Phylogeny ,Plant Proteins ,Oryza sativa ,biology ,Chemistry ,grain yield ,fungi ,Xylem ,food and beverages ,Biological Transport ,Oryza ,biology.organism_classification ,Research Papers ,Cell biology ,030104 developmental biology ,Phenotype ,Shoot ,Cytokinin ,Mutation ,ATP-Binding Cassette Transporters ,Growth and Development ,ABC transporter ,Cytokinin transport ,rice (Oryza sativa L.) ,Edible Grain ,Plant Shoots ,010606 plant biology & botany - Abstract
Cytokinins are one of the most important phytohormones and play essential roles in multiple life processes in planta. Root-derived cytokinins are transported to the shoots via long-distance transport. The mechanisms of long-distance transport of root-derived cytokinins remain to be demonstrated. In this study, we report that OsABCG18, a half-size ATP-binding cassette transporter from rice (Oryza sativa L.), is essential for the long-distance transport of root-derived cytokinins. OsABCG18 encodes a plasma membrane protein and is primarily expressed in the vascular tissues of the root, stem, and leaf midribs. Cytokinin profiling, as well as [14C]trans-zeatin tracer, and xylem sap assays, demonstrated that the shootward transport of root-derived cytokinins was significantly suppressed in the osabcg18 mutants. Transport assays in tobacco (Nicotiana benthamiana) indicated that OsABCG18 exhibited efflux transport activities for various substrates of cytokinins. While the mutation reduced root-derived cytokinins in the shoot and grain yield, overexpression of OsABCG18 significantly increased cytokinins in the shoot and improved grain yield. The findings for OsABCG18 as a transporter for long-distance transport of cytokinin provide new insights into the cytokinin transport mechanism and a novel strategy to increase cytokinins in the shoot and promote grain yield., OsABCG18 is essential for long-distance transport of cytokinins from root to shoot, and promotes grain yield in rice.
- Published
- 2019