Method of identifying compounds that bind galanin receptor (GALR2)

A process involving competitive binding for identifying a chemical compound which specifically binds to a human or rat galanin receptor (GALR2) which comprises separately contacting a membrane fraction from a cell extract of cells transfected with DNA encoding and expressing on their cell surface the human or rat galanin receptor (GALR2), wherein such cells prior to being transfected with such DNA do not express the human or rat galanin receptor (GALR2), with both the chemical compound and a second chemical compound known to bind to the receptor, and with only the second chemical compound, under conditions suitable for binding of both compounds, and detecting specific binding of the chemical compound to the human or rat galanin receptor (GALR2), a decrease in the binding of the second chemical compound to the human or rat galanin receptor (GALR2) in the presence of the chemical compound indicating that the chemical compound binds to the human or rat galanin receptor (GALR2), wherein the human galanin receptor (GALR2) has an amino acid sequence identical to that (a) shown in SEQ ID NO:

• 30, (b) expressed by COS-7 cells transfected with plasmid BO29 (ATCC Accession No. 97735) or (c) expressed by COS-7 cells transfected with plasmid BO39 (ATCC Accession No. 97851), and the rat galanin receptor (GALR2) has an amino acid sequence identical to that (a) shown in SEQ ID NO:
• 8, (b) expressed by LM(tk−) cells transfected with plasmid K985 (ATCC Accession No. 97426) or (c) expressed by LM(tk−) cells transfected with plasmid K1045 (ATCC Accession No. 97778).

A method of screening a plurality of chemical compounds not known to bind to a human or rat galanin receptor (GALR2) to identify a compound which specifically binds to the human or rat galanin receptor (GALR2), which comprises

• (a) contacting cells transfected with and expressing DNA encoding the human or rat galanin receptor (GALR2), wherein such cells prior to being transfected with such DNA do not express the human or rat galanin receptor (GALR2), with a compound known to bind specifically to the human or rat galanin receptor (GALR2);
• (b) contacting the preparation of step (a) with the plurality of compounds not known to bind specifically to the human or rat galanin receptor (GALR2), under conditions permitting binding of compounds known to bind the human or rat galanin receptor (GALR2);
• (c) determining whether the binding of the compound known to bind to the human or rat galanin receptor (GALR2) is reduced in the presence of the compounds, relative to the binding of the compound in the absence of the plurality of compounds;
• and if so
• (d) separately determining the binding to the human or rat galanin receptor (GALR2) of each compound included in the plurality of compounds, so as to thereby identify the compound which specifically binds to the human or rat galanin receptor (GALR2);
• wherein the human galanin receptor (GALR2) has an amino acid sequence identical to that (a) shown in SEQ ID NO:
• 30, (b) expressed by COS-7 cells transfected with plasmid BO29 (ATCC Accession No. 97735) or (c) expressed by COS-7 cells transfected with plasmid BO39 (ATCC Accession No. 37851), and the rat galanin receptor (GALR2) has an amino acid sequence identical to that (a) shown in SEQ ID NO:
• 8, (b) expressed by LM(tk−) cells transfected with plasmid K985 (ATCC Accession No. 97426) or (c) expressed by LM(tk−) cells transfected with plasmid K1045 (ATCC Accession No. 9778).

A method of screening a plurality of chemical compounds not known to bind to a human or rat galanin receptor (GALR2) to identify a compound which specifically binds to the human or rat galanin receptor (GALR2), which comprises

• (a) preparing a cell extract from cells transfected with and expressing DNA encoding the human or rat galanin receptor (GALR2), wherein such cells prior to being transfected with such DNA do not express the human or rat galanin receptor (GALR2), isolating a membrane fraction from the cell extract, contacting the membrane fraction with a compound known to bind specifically to the human or rat galanin receptor (GALR2);
• (b) contacting the preparation of step (a) with the plurality of compounds not known to bind specifically to the human or rat galanin receptor (GALR2), under conditions permitting binding of compounds known to bind the human or rat galanin receptor (GALR2);
• (c) determining whether the binding of the compound known to bind to the human or rat galanin receptor (GALR2) is reduced in the presence of the compounds, relative to the binding of the compound in the absence of the plurality of compounds;
• and if so
• (d) separately determining the binding to the human or rat galanin receptor (GALR2) of each compound included in the plurality of compounds, so as to thereby identify the compound which specifically binds to the human or rat galanin receptor (GALR2);
• wherein the human galanin receptor (GALR2) has an amino acid sequence identical to that (a) shown in SEQ ID NO:
• 30, (b) expressed by COS-7 cells transfected with plasmid BO29 (ATCC Accession No. 97735) or (c) expressed by COS-7 cells transfected with plasmid BO39 (ATCC Accession No. 97851), and the rat galanin receptor (GALR2) has an amino acid sequence identical to that (a) shown in SEQ ID NO:
• 8, (b) expressed by LM(tk−) cells transfected with plasmid K985 (ATCC Accession No. 97426) or (c) expressed by LM(tk−) cells transfected with plasmid K1045 (ATCC Accession No. 97778).