Patent ID: 7108994

Claim:
A method for isolating from a complex mixture a compound capable of binding to RPTP-alpha, comprising: (a) attaching said RPTP-alpha or the ligand-binding portion thereof, to a solid phase matrix; (b) contacting said complex mixture with said solid phase matrix allowing said compound to bind, and washing away any unbound material; and (c) eluting said bound compound, thereby isolating said compound, wherein said RPTP-alpha has protein tyrosine phosphatase activity and comprises: i) the amino acid sequence SEQ ID NO:1; ii) an amino acid sequence encoded by a nucleic acid molecule that hybridizes at 42° C. in 50% formamide, 5×SSC, 25 mM KPO 4 , 5× Denhardt's, 10 μg/ml salmon sperm DNA and 10% sulfate followed by washing at 58° C. in 0.1×SSC and 0.1% SDS to the complement of a nucleic acid molecule comprising the nucleotide sequence of SEQ ID NO: 2; iv) the amino acid sequence of SEQ ID NO: 3; or v) an amino acid sequence encoded by a nucleic acid molecule that hybridizes at 42° C. in 50% formamide, 5×SSC, 25 mM KPO 4 , 5× Denhardt's, 10 μg/ml salmon sperm DNA and 10% sulfate followed by washing at 58° C. in 0.1×SSC and 0.1% SDS to the complement of a nucleic acid molecule comprising the nucleotide sequence of SEQ ID NO:4.