Regulation of glucose transport in differentiating HD3 cells.

Abstract

The chicken erythroblast cell line, HD3, has high glucose transport activity which is lost upon differentiation to the red cell phenotype. HD3 cells, when incubated under conditions where maturation occurs, show substantial loss of GLUT1 and GLUT3 mRNAs. To assess whether cAMP or cellular protein phosphorylation affected GLUT mRNA and protein, the HD3 cells were incubated in the presence of different phosphatase inhibitors. Treatment of HD3 cells with the phosphatase inhibitors okadaic acid, vanadate or with 3-isobutyl-1-methyl-xanthine induced glucose transport and GLUT mRNAs. This suggests that phosphorylation events enhance glucose transport and that their reduction may be involved in the decrease in glucose transport that occurs upon HD3 cells differentiation.