Expression vectors that produce steroid receptors, steroid receptor chimera, screening assays for steroid receptors and clinical assays using synthesized receptors and receptor vectors

摘要

The present invention relates to a method for making an expression vector which produces a biological active receptor. The method includes synthesizing a linker having the carboxyl six amino acids of ubiquitin and an internal restriction site and cloning the synthesized linker to form a plasmid. The plasmid is then digested with a restriction endonuclease which is compatible with the internal restriction site in the synthesized linker. After the digestion of the plasmid a cDNA coding for the receptor is inserted into the compatible restriction site and the plasmid is then used to transform yeast. In the procedure, the yeast that is usually used is from the strains of Saccharomyce and Aspergillus. In addition, numerous vectors which express the human vitamin D receptor, human androgen receptor, human progesterone receptor, thyroid receptor, retinoic acid receptor, chicken progesterone receptor, chicken vitamin D receptor, rat vitamin D receptor and COUP protein are described. A further aspect of the invention is the reporter vector which includes the proximal promoter element of the yeast iso-l-cytochrome C and a structural gene selected from E. coli either the ö-Galactosidase gene or the Galactokinase gene. The reporter vector is used to detect for agonist and antagonists for the steroid hormone receptor. A further element of the invention is a chimera made up of the DNA binding domain from one receptor and the hormone binding domain from another receptor. The chimera is used in an assay to identify the function of the unknown receptor component. Additional aspects are clinical and laboratory assays for biological compounds using the receptors synthesized from the expression vectors and using receptor vectors.