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


Autoria(s): Gospe, SM; Baker, SA; Arshavsky, VY
Data(s)

01/11/2010

Formato

3639 - 3644

Identificador

http://www.ncbi.nlm.nih.gov/pubmed/20923839

jcs.072389

J Cell Sci, 2010, 123 (Pt 21), pp. 3639 - 3644

http://hdl.handle.net/10161/4190

1477-9137

Idioma(s)

ENG

en_US

Relação

J Cell Sci

10.1242/jcs.072389

Journal of cell science

Palavras-Chave #Animals #Animals, Genetically Modified #Facilitated Diffusion #Glucose #Glucose Transporter Type 1 #Mice #Mice, Inbred Strains #Mutagenesis, Site-Directed #Photoreceptor Connecting Cilium #Protein Engineering #Protein Sorting Signals #Protein Transport #Rats #Retinal Photoreceptor Cell Inner Segment #Rod Cell Outer Segment #Sequence Deletion #Transgenes #Xenopus laevis
Tipo

Journal Article

Cobertura

England

Resumo

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.