A single amino acid change converts the sugar sensor SGLT3 into a sugar transporter.

ABSTRACT:

Background

Sodium-glucose cotransporter proteins (SGLT) belong to the SLC5A family, characterized by the cotransport of Na(+) with solute. SGLT1 is responsible for intestinal glucose absorption. Until recently the only role described for SGLT proteins was to transport sugar with Na(+). However, human SGLT3 (hSGLT3) does not transport sugar but causes depolarization of the plasma membrane when expressed in Xenopus oocytes. For this reason SGLT3 was suggested to be a sugar sensor rather than a transporter. Despite 70% amino acid identity between hSGLT3 and hSGLT1, their sugar transport, apparent sugar affinities, and sugar specificity differ greatly. Residue 457 is important for the function of SGLT1 and mutation at this position in hSGLT1 causes glucose-galactose malabsorption. More

SUBMITTER: Bianchi L 

PROVIDER: S-EPMC2857651 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature