摘要
We report the characterization of magnesium (Mg) transport from external solution to xylem by using xylem fluid analysis in rice (Oryza sativa L. Nipponbare). It was indicated that Mg uptake and/or xylem loading was mediated by two transport systems, a saturable and a linear component. The Km value of the saturable component was approximately 20 mu M, and the saturated concentration was calculated to be 1.5 mM. Using a multi-compartment transport box with excised roots, the transfer from external solution to xylem was shown to be inhibited by hexaamminecobalt(III) {[Co(III)(NH3)6], Co-Hex}, a selective inhibitor of CorA-mediated influx of Mg2+, suggesting that the MRS2/MGT genes that belong to the superfamily of CorA-type membrane proteins are involved in the Mg transport system.
- 出版日期2011-4