CLONING AND EXPRESSION OF CDNA-ENCODING HUMAN PLACENTAL ESTROGEN SULFOTRANSFERASE

Using two oligoprimers derived from the bovine placental estrogen sulf otransferase sequence, we amplified a probe for human placental estrog en sulfotransferase. Using this probe to screen a human placental cDNA library constructed in lambda gt11, we isolated a cDNA clone of 1.3 k b encoding human estrogen sulfotransferase. DNA analysis predicts a pr otein of 295 amino acids with a calculated molecular weight of 34199. Alignment of the amino acid sequence with other sulfotransferases indi cates that human placental estrogen sulfotransferase shares 68.6, 68.2 and 65.9% similarity with bovine placental, guinea pig adrenocortical , and rat liver estrogen sulfotransferase, respectively. It shows also 95.6, 57.6, 85.3, and 54.2% similarity to human phenol, human DHEA, r at phenol, and rat hydroxysteroid sulfotransferase, respectively. Tran sfection of expression vectors encoding human estrogen sulfotransferas e and dehydroepiandrosterone (DHEA) sulfotransferase in human adrenal adenocarcinoma SW-13 cells indicates that estrogen sulfotransferase tr ansforms estrone more specifically, whereas DHEA sulfotransferase is m ore specific for DHEA and pregnenolone.