10 NUCLEOTIDE CIS-ELEMENT IN THE 3'-UNTRANSLATED REGION OF THE GLUT1 GLUCOSE-TRANSPORTER MESSENGER-RNA INCREASES GENE-EXPRESSION VIA MESSENGER-RNA STABILIZATION

The GLUT1 glucose transporter gene is regulated at the post-transcript ional level, and a 10 nucleotide (nt) cis-acting element located at nt 2181-2190 of the GLUT1 3'-untranslated region (3'-UTR) increases the transient expression of a luciferase reporter gene. To investigate the role of this mRNA cis-element, stable transfectants expressing lucife rase reporter genes were established in rat C6 glioma cells. Insertion of nt 2100-2300 of GLUT1 3'-UTR resulted in a marked increase in the abundance of both reporter gene mRNA and protein compared to the contr ol, in parallel with a 228% increase in the mRNA t(1/2) determined wit h actinomycin D. Deletion of the 10 nt cis-acting element in the GLUT1 3'-UTR reduced the abundance of reporter gene products and the mRNA t (1/2) to levels similar to the control clone. Data suggest that the ci s-acting element located at nt 2181-2190 of bovine GLUT1 mRNA 3'-UTR i s responsible for increased GLUT1 gene expression via enhanced GLUT1 m RNA stabilization. (C) 1998 Elsevier Science B.V. All rights reserved.