Expression of a sugar-transporter gene family in a photoautotrophic suspension culture of Chenopodium rubrum L.

Photoautotrophic suspension-culture cells of Chenopodium rubrum L. were shifted to mixotrophic growth by adding glucose to investigate whether the activities of plant sugar transporters, as well as the expression of the corresponding genes, are regulated in response to sugars. The rate of D-glucose uptake was shown not to be affected by mixotrophic growth in the presence of D-glucose. The polymerase chain reaction (PCR) technique was applied to amplify cDNA and genomic fragments from monosaccharide-carrier genes. Seven members of a monosaccharide-carrier family were identified of which three were found to be expressed in the suspension-culture cells. The expression of the monosaccharide-carrier genes was independent of the presence of D-glucose.