The facilitative glucose transporter 2: pathophysiological role in mouse and human

Abstract

Glucose is an essential substrate for the metabolism of most cells. Because glucose is a polar molecule, its transport through biological membranes requires specific transporter proteins. Transport of glucose through the apical membrane of intestinal and kidney epithelial cells depends on the presence of active Na+/glucose symporters, SGLT-l and SGLT-2, which concentrate glucose inside the cells using the energy provided by cotransport of Na+ ions down their electrochemical gradient (Hediger and Rhoads 1994). Facilitated diffusion of glucose through the cellular membrane is otherwise catalyzed by glucose carriers (protein symbol GLUT, gene symbol SLC2 for Solute Carrier Family 2) that belong to a superfamily of transport facilitators which comprises organic anion and cation transporters, yeast hexose transporters, plant hexose/proton symporters, and bacterial sugar/ proton symporters (Henderson 1993).