Mediates sugar transport across membranes (By similarity). May regulate the expression of RAG1 a gene involved in V(D)J recombination. Interacts with TRPV2; the interaction probably occurs intracellularly and depends on TRPV2 N-glycosylation. May also localize to the endoplasmic reticulum. Expressed at high levels in lung, placenta, spleen and thymus, at intermediate levels in brain, heart, kidney and testis, and at low levels in bone marrow, liver and lymph node. Within the thymus expression is highest in non-lymphoid cells. Up-regulated in mammary gland during lactation. Belongs to the SWEET sugar transporter family.