GLUT8

GLUT8 also known as SLC2A8 is the eighth member of glucose transporter superfamily.

It is characterized by the presence of two leucine residues in its N-terminal intracellular domain, which influences intracellular trafficking.

Discovery

GLUT8, originally named GLUTX1, was cloned almost simultaneously by two different groups.

Tissue distribution

GLUT8 is expressed mostly in neurons and testis, although expression in most other tissues has also been shown at lower levels. GLUT8 is expressed at moderate levels in the brain, most strikingly in hippocampus. Whether the glucose transporter plays any role in these cells remains to be shown.

Subcellular localization

Contrary to GLUT4, GLUT8 (previously known as GLUTX1) is not insulin-sensitive. In other words, insulin does not promote GLUT8 translocation to the cell surface in neurons as well as in transfected cell lines.

Where in the cell GLUT8 is localized in not yet clear. Most GLUT8 is not present at the cell surface. Some co-localization with both the endoplasmic reticulum and late endosomes/lysosomes has been published.