SUBSTITUTION OF ALA(564) IN THE FIRST ZINC CLUSTER OF THE DEOXYRIBONUCLEIC-ACID (DNA)-BINDING DOMAIN OF THE ANDROGEN RECEPTOR BY ASP, ASN, OR LEU EXERTS DIFFERENTIAL-EFFECTS ON DNA-BINDING

In the androgen receptor of a patient with androgen insensitivity, the alanine residue at position 564 in the first zinc cluster of the DNA- binding domain was substituted by aspartic acid. In other members of t he steroid receptor family, either valine or alanine is present at the corresponding position, suggesting the importance of a neutral amino acid residue at this site. The mutant receptor was transcriptionally i nactive, which corresponded to the absence of specific DNA binding in gel retardation assays, and its inactivity in a promoter interference assay. Two other receptor mutants with a mutation at this same positio n were created to study the role of position 564 in the human androgen receptor on DNA binding in more detail. Introduction of asparagine at position 564 resulted in transcription activation of a mouse mammary tumor virus promoter, although at a lower level compared with the wild -type receptor. Transcription activation of an (ARE)(2)-TATA promoter was low, and binding to different hormone response elements could not be visualized. The receptor with a leucine residue at position 564 was as active as the wild-type receptor on a mouse mammary tumor virus pr omoter and an (ARE)(2)-TATA promoter, but interacted differentially wi th several hormone response elements in a gel retardation assay. The r esults of the transcription activation and DNA binding studies could p artially be predicted from three-dimensional modelling data. The pheno type of the patient was explained by the negative charge, introduced a t position 564.