Insulin-independent facilitative glucose transporter. D-glucose(out) = D-glucose(in) Localizes primarily perinuclear region in the absence of insulin. Expressed in skeletal muscle, heart, brain, kidney, spleen, adipose tissues and to a lesser extent in small intestine and lung. Expression is clearly detected in ovulated oocytes and 2-cells embryos but decline day 3 morulae. Remains at very low levels between 2 dpc and 11 dpc. Belongs to the major facilitator superfamily. Sugar transporter (TC 2.A.1.1) family. Glucose transporter subfamily.