R. Onetti et al., INCREASED GLUCOSE-TRANSPORT IN RAS-TRANSFORMED FIBROBLASTS - A POSSIBLE ROLE FOR N-GLYCOSYLATION OF GLUT1, FEBS letters, 407(3), 1997, pp. 267-270
2-Deoxyglucose uptake was enhanced in ts371 MiMuSV-NRK cells when grow
ing at the permissive temperature to allow the expression of a transfo
rming p21 ras protein. This change is due to a decrease in the K-m by
approximately 2.5-fold without affecting the V-max of the transporter.
The amount of the GLUT1 glucose transporter dit not increase as deduc
ed from imnunoblot experiments on total membranes. Nevertheless, ras-t
ransformed GLUT1 displays a higher molecular mass due to an increased
N-glycosylation of the protein. Experiments made in tunicamycin-treate
d cells indicates that a higher glycosylation is responsible for the i
ncrease in 2-deoxyglucose uptake in ras-transformed cells. (C) 1997 Fe
deration of European Biochemical Societies.