Functional expression of a plant plasma membrane transporter in Xenopus oocytes

[摘要]

A full-length cDNA clone for the H⁺/hexose co-transporter (STP1) from Arabidopsis thaliana has been transcribed in vitro and the mRNA injected into Xenopus oocytes. Under optimized conditions, oocytes injected with the STPI mRNA accumulated 3-O-[methyl-¹⁴C]glucose at rates of more than a 1000-fold greater than water-injected control oocytes. A hexose-elicited depolarization of the oocyte membrane potential was demonstrated, and uptake was shown to be stimulated by low external pH, confirming the activity of a H⁺/hexose co-transport system. This is the first example of the functional expression of a plant membrane transporter in oocytes.

[学科分类] 生物化学/生物物理

[关键词] Arabidopsis thaliana;Hexose transporter;Proton symporter;Heterologous expression;Xenopus oocyte;3-OMG;3-O-methylglucose;MBS;modified Barth's saline;SDS;sodium dodecyl sulphate