Mediates active uptake of hexoses by sugar:proton symport (Probable). Can transport glucose, fructose, mannose, galactose, xylose and ribose (PubMed:18506478). Expressed in leaf blades, leaf sheaths, anthers, ovaries and embryos. Expressed at low levels in roots and shoots. Induced by glucose, sucrose and salt stress. Belongs to the major facilitator superfamily. Sugar transporter (TC 2.A.1.1) family.