Class I facilitative glucose transporter (GLUT (with isoforms designated as GLUT1, GLUT2, GLUT3, GLUT4, and GLUT14))

Class I facilitative glucose transporters are a subfamily of glucose carriers encoded by SLC2A genes, mainly consisting of GLUT1, GLUT2, GLUT3, GLUT4, and GLUT14. These transporters span the cell membrane via 12 transmembrane domains and function via facilitative diffusion, moving glucose and related sugars along their concentration gradient. Each isoform has distinct tissue expression—GLUT1 is found ubiquitously and in barrier tissues such as the blood-brain barrier, GLUT2 is important in liver, pancreas, and kidney for bidirectional glucose transport, GLUT3 is neuron-specific, GLUT4 is insulin-regulated and found in muscle and adipose tissue, and GLUT14 is testis-specific. Class I glucose transporters are critical for cellular energy metabolism and are implicated in diverse pathophysiologies, especially cancer (where GLUT1 is often overexpressed), metabolic diseases, and neurological disorders. Several small molecules and experimental drugs target these transporters, aiming primarily at inhibiting glucose uptake to block tumor growth. However, clinical development is challenged by their widespread expression and vital physiological role[1][2][3][5][6][7][8].

Other names

Class I GLUTSLC2A family (includes SLC2A1 [GLUT1], SLC2A2 [GLUT2], SLC2A3 [GLUT3], SLC2A4 [GLUT4], SLC2A14 [GLUT14])Glucose transporter

Competitive inhibition of glucose binding site (e.g., cytochalasin B, WZB117); Allosteric modulation of transporter conformation