AU-rich elements in the mRNA 3'-untranslated region of the rat receptor for advanced glycation end products and their relevance to mRNA stability.

Several putative polyadenylation sequences and an adenylate plus timidylate rich element (ARE) are present at the 3' end of the rat advanced glycation end products receptor (RAGE) gene. Two transcripts are generated by the use of alternative polyadenylation sequences, one containing the ARE sequence in its 3'-untranslated region (3'-UTR). Transfections of CHO-k1 or NRK cells with constructs expressing the 3'-UTRs of the transcripts fused to a green fluorescence protein mRNA show that the ARE sequence has a negative effect on protein expression correlating with a decrease in the amount of mRNA, as shown in CHO-k1 transfected cells. When transfected cells were incubated in the presence of Actinomycin D the amount of fluorescence decreased in cells transfected with the ARE sequence, indicating that this sequence induces lower mRNA stability. Thus, alternative polyadenylation signals and an ARE sequence provide a novel mechanism for the regulation of the rat RAGE gene expression.