Facilitative glucose transporter Glut1 is actively excluded from rod outer segments.

Journal Article (Journal Article)

Photoreceptors are among the most metabolically active cells in the body, relying on both oxidative phosphorylation and glycolysis to satisfy their high energy needs. Local glycolysis is thought to be particularly crucial in supporting the function of the photoreceptor's light-sensitive outer segment compartment, which is devoid of mitochondria. Accordingly, it has been commonly accepted that the facilitative glucose transporter Glut1 responsible for glucose entry into photoreceptors is localized in part to the outer segment plasma membrane. However, we now demonstrate that Glut1 is entirely absent from the rod outer segment and is actively excluded from this compartment by targeting information present in its cytosolic C-terminal tail. Our data indicate that glucose metabolized in the outer segment must first enter through other parts of the photoreceptor cell. Consequently, the entire energy supply of the outer segment is dependent on diffusion of energy-rich substrates through the thin connecting cilium that links this compartment to the rest of the cell.

Full Text

Duke Authors

Cited Authors

  • Gospe, SM; Baker, SA; Arshavsky, VY

Published Date

  • November 1, 2010

Published In

Volume / Issue

  • 123 / Pt 21

Start / End Page

  • 3639 - 3644

PubMed ID

  • 20923839

Pubmed Central ID

  • PMC2964109

Electronic International Standard Serial Number (EISSN)

  • 1477-9137

Digital Object Identifier (DOI)

  • 10.1242/jcs.072389


  • eng

Conference Location

  • England