Isolation of cDNAs and tissue specific expression of ovine glucose transporters.

The facilitative glucose transporters are a family of proteins responsible for the transmembrane transport of glucose and other hexose sugars (1,2). In mammals, the seven glucose transporter isoforms display a characteristic tissue distribution reflecting the physiological requirement and metabolism of glucose. This report describes the isolation and sequencing of the full length ovine GLUT-3 cDNA and the tissue distribution of ovine GLUT-1 and GLUT-3 mRNA. The ovine GLUT-3 cDNA is 3854 base pairs and the coding nucleotides show 82% and 79% homology with the human and mouse GLUT-3 sequences respectively. In addition, a reverse transcriptase-polymerase chain reaction strategy is described for the rapid isolation of mammalian cDNA subclones for GLUT-1, GLUT-2 and GLUT-4. This method has been used to isolate the corresponding ovine subclones.