VvpGLT, a grapevine gene encoding for a plastidic localized glucose transporter

Abstract

Glucose transporters mediate the membrane transport of a variable range of glucose, which play a crucial role in sugar distribution throughout the plant. To investigate the significance of glucose transporters during grapevine (Vitis vinifera L.) fruit development, a cDNA clone of a putative glucose transporter gene VvpGLT was isolated by screening the grapevine cDNA library. Phylogenetic comparison of the amino acid sequences showed the highest similarity to the AtpGLcT gene from Arabidopsis thaliana. The 1,629 bp VvpGLT cDNA clone was heterologously expressed in yeast resulting that VvpGLT was able to work as a glucose transporter in Saccharomyces cerevisiae, suggesting that VvpGLT is a gene that encodes for a glucose transporter. Induction of VvpGLT-GFP fusion protein expression in transgenic yeast and VvpGLT-GFP transient expression in onion epidermal cells revealed its plastidic localization. Based on the above analyses of VvpGLT, this is the first report of a functional plastidic localized glucose transporter in grapevine. © Springer-Verlag Berlin Heidelberg 2014.