Identification and characterization of the 5'-flanking region of the rat galanin gene

Abstract

Galanin, a neuropeptide widely distributed throughout the central and eripheral nervous systems, is a biologically active peptide which is strongly upregulated by nerve injury, estrogen and during development by mechanisms largely unknown. Here I present the initial molecular and functional characterization of the promoter region of the rat galanin gene. A rat genomic clone containing at least 4.5 kb $5\sp\prime$-flanking sequence has been isolated by PCR method. Partial sequence analysis of the clone revealed that the structure of the rat galanin conserved gene is very conserved among species. Similar to the bovine, human and mouse genes, the rat gene has several transcriptional factor binding site consensus sequences such as SP1, AP-1, ERE$\sb{1/2},$ CREB. To locate functionally active regulatory elements of the rat galanin gene we have constructed plasmids containing various lengths of the rat galanin $5\sp\prime$-flanking sequence and the first exon, fused into a promoterless luciferase reporter plasmid. These hybrid genes were transfected into the human neuroblastoma (SK-N-MC) cell line, the rat pheochromocytoma (PC$\sb{12}$) cell line, the rat pituitary tumour cell line (GH$\sb3)$ and the Hela cell line, by transient transfection. (Abstract shortened by UMI.)