# US 5,700,682 A · Mechanism based screen for retinoid X receptor agonists and antagonists > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,700,682 A - Document ID: US5700682A - Status: Granted - Kind: A - Application number: 08/465,783 - Filed: 1995-06-06 - Granted: 1997-12-23 - Earliest claimed: 1992-12-31 - Assignees: American Cyanamid Company - Inventors: Paul Mak; Sotirios K. Karathanasis - Web page: https://patentgrep.com/patent/US5700682A ## CPC - G01N 33/566: using specific carrier or receptor proteins as ligand binding reagents {where possible specific carrier or receptor proteins are classified with their target compounds} - C07K 14/70567: {Nuclear receptors, e.g. retinoic acid receptor [RAR], RXR, nuclear orphan receptors} - C07K 14/775: Apolipopeptides - C12Q 1/6897: involving reporter genes operably linked to promoters - G01N 2333/395: from Saccharomyces - G01N 2333/70567: Nuclear receptors, e.g. retinoic acid receptor [RAR], RXR, nuclear orphan receptors - G01N 2500/00: Screening for compounds of potential therapeutic value - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - C07K: PEPTIDES (peptides in foodstuffs A23; obtaining protein compositions for foodstuffs, working-up proteins for foodstuffs A23J; preparations for medicinal purposes A61K; peptides containing beta-lactam rings C07D; cyclic dipeptides not having in their molecule any other peptide link than those which form their ring, e.g. piperazine-2,5-diones, C07D; ergot alkaloids of the cyclic peptide type C07D519/02; macromolecular compounds having statistically distributed amino acid units in their molecules, i.e. when the preparation does not provide for a specific; but for a random sequence of the amino acid units, homopolyamides and block copolyamides derived from amino acids C08G69/00; macromolecular products derived from proteins C08H1/00; preparation of glue or gelatine C09H; single cell proteins, enzymes C12N; genetic engineering processes for obtaining peptides C12N15/00; compositions for measuring or testing processes involving enzymes C12Q; investigation or analysis of biological material G01N33/00) - C12Q: MEASURING OR TESTING PROCESSES INVOLVING ENZYMES, NUCLEIC ACIDS OR MICROORGANISMS (immunoassay G01N33/53); COMPOSITIONS OR TEST PAPERS THEREFOR; PROCESSES OF PREPARING SUCH COMPOSITIONS; CONDITION-RESPONSIVE CONTROL IN MICROBIOLOGICAL OR ENZYMOLOGICAL PROCESSES ## Abstract A method is described for screening retinoid X receptor agonists or antagonists using a retinoid X receptor expressed by a yeast expression system to screen a compound having a retinoid X receptor agonist or antagonist activity. Another screen is described for detecting a compound having retinoid X receptor agonist or antagonist activity by: (1) providing a yeast strain which expresses the retinoic acid receptor and activates a reporter plasmid containing apolipoprotein AI gene site A or a mutated variant thereof; (2) incubating the compound in suitable media and a colorless chromogenic substrate; and (3) examining the media for development of color. Mutated variants of apolipoprotein AI gene site A which respond selectively to the retinoid X receptor or respond to receptors other than RXR.alpha. are also described. ## Claims ### Claim 1 A prokaryotic or eukaryotic host cell stably transformed or transfected by an expression vector containing a cDNA sequence encoding a retinoid X receptor and a reporter plasmid containing an apolipoprotein AI gene site A mutant comprising a nucleotide sequence selected from the group consisting of SEQ ID NOS: 7-15 and 17. ### Claim 2 (depends on 1) The host cell according to claim 1, which comprises a yeast strain carrying an expression vector identified as BJ YEpRXR.alpha., having the ATCC designation number 74197. ### Claim 3 (depends on 1) The host cell according to claim 1, which comprises a yeast strain carrying an expression vector and a reporter plasmid identified as BJ YEpRXR.alpha./YRpA, having the ATCC designation number 74196. ### Claim 4 (depends on 1) The host cell according to claim 1, which comprises a yeast strain carrying a reporter plasmid identified as BJ YRpA, having the ATCC designation number 74195. ### Claim 5 (depends on 1) The host cell according to claim 1, which comprises a DH5.alpha. strain of E. coli carrying an expression vector identified as YEpRXR.alpha., having the ATCC designation number 69145. ### Claim 6 (depends on 1) The host cell according to claim 1, which comprises a DH5.alpha. strain of E. coli carrying a reporter plasmid identified as YRpA, having the ATCC designation number 69144. ### Claim 7 An HB101 strain of E. coli carrying the reporter plasmid identified as ›M6!-41AI.CAT, having the ATCC designation number 69169. ### Claim 8 An HB101 strain of E. coli carrying the reporter plasmid identified as ›M4!-41AI.CAT, having the ATCC designation number 69170. ### Claim 9 An HB101 strain of E. coli carrying the reporter plasmid identified as ›M3!-41AI.CAT, having the ATCC designation number 69168. ### Claim 10 A gene sequence comprising a nucleotide sequence comprising two TGACC imperfect direct repeats separated by the trinucleotide spacer CCT having the nucleotide sequence of SEQ ID NO: 10, wherein the protein expressed by said gene sequence responds selectively to a retinoid x receptor. ### Claim 11 A gene sequence comprising a nucleotide sequence comprising two TGACC imperfect direct repeats separated by the trinucleotide spacer TTT having the nucleotide sequence of SEQ ID NO: 8 or SEQ ID NO: 9, wherein the protein expressed by said gene sequence responds to a receptor other than a retinoid X receptor.