Involvement of a Low-P Induced Glycerol-3-Phosphate Transporter, GmGLPT1, in Soybean Sucrose/Phosphorus Antiport

摘要

The major facilitator superfamily represents the largest group of secondary membrane transporters in the cell. Here we report a member of this superfamily, GmGLPT1, which is induced by low-phosphorus ( P) and involved in the sucrose/ phosphate antiport. Quantitative PCR analysis showed that the expression level of GmGLPT1 was strongly increased by P starvation after long-term low P treatment. Furthermore, its expression patterns under low P conditions were different in two soybean genotypes contrasting in P efficiency, the tendency was similar with that of the sucrose concentration in plants. Constitutively overexpression of GmGLPT1 in soybean hairy roots resulted in the accumulation of sucrose and the efflux of P in the roots, implying that GmGLPT1 might be involved in sucrose/phosphorus antiport. Subcellular localization of GmGLPT1 proteins fused to GFP after transient transformation using onion epidermal cells showed that it was localized to the plasma membrane.