| Most mammalian cells transport glucose through a family of membrane proteins known as glucose transporters. Molecular cloning of these glucose transporters has identified a family of closely related genes that encodes at least 7 proteins (Glut-1 to Glut-7, Mol. Wt. 40-60kD) and Sodium glucose co-transporter-1 (SGLT-1, 662 amino acids, ~75kD). Individual member of this family have identical predicted secondary structures with 12 transmembrane domains. Both N and c-termini are predicted to be cytoplasmic. Most differences in sequence homology exist within the four hydrophilic domains that may play a role in tissue-specific targeting. Glut isoform differ in their tissue expression, substrate specificity and kinetic characteristics. Glut-1 mediates glucose transport into red cells, and throughout the blood brain barrier, and supply glucose to most cells. Glut-2 provides glucose to the liver and pancreatic cells. Glut-3 is the main transporter in neurons, whereas Glut-4 is primarily expressed in muscle and adipose tissue and regulated by insulin. Glut-5 transports fructose in intestine and testis. Glut-6/SLC2A6, originally described as glut-9 has been reassigned as Glut-6. Glut-6 (human 507 aa, ~ 48kD, chromosome 9q34) is most closely related to Glut-8 (~45% homology). It is highly expressed in brain, spleen, and peripheral leukocytes. Glut-7, expressed in liver and other gluconeogenic tissues, mediates glucose flux across endoplasmic reticulum membrane. Glut-8 is found in adult testis and placenta. Human Glut-9 is expressed in spleen, peripheral leukocytes and brain. Human Glut-10 (541 aa, chromosome 20q13.1, ~30-35% homology with Glut-3 and Glut-8) has been identified as a candidate gene for NIDDM susceptibility. It is widely expressed with highest levels in liver and pancreas. Glut-11 (496 aa, chromosome 22q11.2, ~41% identity with Glut-5) is expressed in heart and skeletal muscle. Glut-12 (human 617 aa, , monkey 621 aa,~ 50kD, ~30% homology with Glut-4 and 40% with Glut-10) is expressed in skeletal muscle, adipose tissue, and small intestine . glut 13 or proton myo-inositol transporter (HMIT, human 629 aa, rat 618 aa, ~75-90kD/67kD protein) is highly expressed in glial cells and some neurons. Glut-13 transport activity was specific for myo-inositol. Rat HMIT is ~35% identical to rat GlutX1. Source: 13aa peptide from human GLUT 3 Location: ~N-terminus, Extracellular Applications: ELISA: Control peptide can be used to coat ELISA plates at 1ug/ml and detected with antibodies (See ). Species Sequence Homology: 100% identical in human GLUT 3 (brain and skeletal muscle), and 92% with GLUT 14 (duplicon of GT3) short and long form. Storage and Stability: Lyophilized powder may be stored at -20C. Stable for 12 months at -20C. Reconstitute with sterile buffer or ddH2O. Aliquot to avoid repeated freezing and thawing. Store at -20C. Reconstituted product is stable for 6 months at -20C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer. |
