DISTRIBUTION OF MAMMALIAN FACILITATIVE GLUCOSE-TRANSPORTER MESSENGER-RNA IN BOVINE-TISSUES

1. The complementary DNA for five human facilitative glucose transport ers (GLUT1, GLUT2, GLUT3, GLUT4 and GLUT5) were used to determine the distribution of facilitative glucose transporter mRNA in bovine tissue s by Northern blotting. Under high stringency hybridization conditions , a single 2.8 kb transcript of GLUT1 was seen in all bovine tissues e xamined except liver. Mammary gland had the highest abundance of GLUT1 mRNA. 2. Four GLUT2 transcripts of 6.3, 3.8, 2.2 and 1.6 kb were obse rved to be most abundant in liver, with lower abundance in kidney and duodenum. 3. Only a very low level of GLUT3 mRNA was detected in the m ammary gland, skeletal muscle and duodenum. 4. Skeletal muscle contain ed the greatest abundance of GLUT4 mRNA, which was barely detectable i n omental fat, kidney and mammary gland. 5. Transcripts of GLUT5 mRNA were detected in relatively high abundance in liver and kidney, and in lower abundance in the duodenum and mammary gland. 6. With the except ion of the mammary gland, for which human data have not been reported, the distributions of GLUT1, 2 and 4 mRNA for the bovine tissues exami ned are similar to that reported for humans. On the other hand, the di stributions of GLUT3 and 5 mRNA in the bovine differ from those report ed for humans.