Organization of a rainbow trout estrogen receptor gene

The complete coding region of the estrogen receptor gene was isolated from a rainbow trout genomic library. This gene is divided into ten exons spanning at least 30 kb of genomic DNA. With two exceptions, intron positions are identical to those of the human estrogen receptor gene. The 5' end of the gene, including 1.7 kb of the promoter region, was sequenced. This region exhibits several putative regulatory elements. Localization of a potential estrogen responsive element to the first exon suggests that this gene is autoregulated. This 5' end region was also shown to be able to drive the expression of a CAT reporter gene in Xenopus laevis oocytes.