We tested if glut4, the gene for muscle-specific glucose transporter,
underwent some variations of expression in neoplastic cells. Our model
was a rhabdomyosarcoma cell line (RD18) which retains the ability to
differentiate along the myogenic pathway. Any definable changes of exp
ression of glut4 in normal and RD18 cells were revealed by Northern bl
ot analysis. In order to identify the transcriptional regulatory regio
ns of the glut4 gene we performed a deletion analysis of the 5' flanki
ng region. The downregulation which we found in the expression of this
gene in RD 18 cells could be related with the activity of a negative
regulatory element.