Oestrogen Sulfotransferase: Molecular Cloning and Sequencing of cDNA for the Bovine Placental Enzyme

Abstract

The female sex hormone, oestrogen, plays a central role in breast cell proliferation in both the normal and malignant state. It controls transcription from several genes, including that for the progesterone receptor, and in endometrial tissue, via this receptor, it controls the gene for the enzyme oestrogen sulfotransferase. This enzyme may control the level of the oestrogen receptor by sulfurylating free oestradiol. To study the mode of transcriptional control exercised by oestrogen, bovine oestrogen sulfotransferase cDNA has been cloned and the nucleotide sequence determined. The message, of which 1812 bases have been sequenced, contains an open reading frame of 885 bases which encode a protein of 295 amino acids and a maximum apparent molecular weight of 34 600. The deduced protein sequence is supported by existing peptide sequence data and appears to contain a steroid-binding region. Some physico-chemical characteristics of the enzyme appear to differ markedly from those previously reported.