THE HUMAN NORADRENALINE TRANSPORTER GENE CONTAINS MULTIPLE POLYADENYLATION SITES AND 2 ALTERNATIVELY SPLICED C-TERMINAL EXONS

Sequencing downstream of the C-terminal exon 14 of the human noradrena line transporter (hNAT) gene reveals 5 consensus polyadenylation signa ls, several adenylate/uridylate-rich elements (AREs) and a new C-termi nal exon, designated as exon 15. The tandemly arranged polyadenylation sites are in good conformity with the 3.6- and 5.8-kb hNAT mRNA trans cripts. Expression of the alternatively spliced C-terminal exon 15 is shown by RT-PCR. This alternative splicing event proposes additional h NAT mRNA species of 2.4-3 kb in size. Corresponding NAT transcripts ar e found by Northern analysis of human SKN and rat PC 12 cell RNA. Sequ ence comparison of the hNAT gene to two bovine NAT cDNAs shows the int erspecies conservation of this alternative splicing event, the close r elationship of human and bovine NAT genes, and implicates a functional role for the transporters C-terminal domain. (C) 1998 Elsevier Scienc e B.V. All rights reserved.