Abstract: A novel expression cloning method is provided for the detection, identification and purification of target proteins capable of binding at least to a tryosine-phosphorylated domain of a eukaryotic tyrosine kinase using novel peptide probes comprising an amino acid sequence substantially corresponding to a portion of a tyrosine-phosphorylated domain of a tyrosine kinase. The probe has at least one phosphorlated tyrosine residue and may be detectably labeled. Also disclosed is a method for preparing the probe, a method for mapping to a chormosome a gene encoding a protein capable of binding to tyrosine-phosphorylated domains of tyrosine kinases, and a method for purifiying such a protein with the probe. Non-limiting examples of novel proteins/discovered using the above cloning method include GRB-1, GRB-2, GRB-3, GRB-4 and GRB-7, as well as nucleic acid encoding these proteins, and methods for detecting these proteins are also provided.

Abstract: A novel expression cloning method is provided for the detection, identification and purification of target proteins capable of binding at least to a tryosine-phosphorylated domain of a eukaryotic tyrosine kinase using novel peptide probes comprising an amino acid sequence substantially corresponding to a portion of a tyrosine-phosphorylated domain of a tyrosine kinase. The probe has at least one phosphorlated tyrosine residue and may be detectably labeled. Also disclosed is a method for preparing the probe, a method for mapping to a chormosome a gene encoding a protein capable of binding to tyrosine-phosphorylated domains of tyrosine kinases, and a method for purifiying such a protein with the probe. Non-limiting examples of novel proteins discovered using the above cloning method include GRB-1, GRB-2, GRB-3, GRB-4 and GRB-7, as well as nucleic acid encoding these proteins, and methods for detecting these proteins are also provided.

Abstract: A novel receptor-type protein tyrosine phosphatase-.beta. (RPTP.beta.) protein or glycoprotein, and the DNA coding therefor is disclosed. This protein is naturally expressed in the brain and in neural cell lines. The RPTP.beta. protein or glycoprotein may be produced by recombinant means. Antibodies to the protein, methods for measuring the quantity of the protein, methods for screening compounds, such as drugs, which can bind to the protein and inhibit or stimulate it phosphatase enzymatic activity, are provided.

Abstract: A novel receptor-type protein tyrosine phosphatase (RPTP) protein or glycoprotein and the DNA coding therefor is expressed in a wide variety of mammalian tissues. Included in this family of proteins are human RPTP.alpha., human RPTP.beta. and human RPTP.gamma.. The RPTP protein or glycoprotein may be produced by recombinant means. Antibodies to the proteins, methods for measuring the quantity of the proteins, methods for screening compounds, such as drugs, which can bind to the proteins and inhibit or stimulate their activity, are provided.

Abstract: A novel receptor-type protein tyrosine phosphatase-.gamma. (RPTP.gamma.) protein or glycoprotein and the DNA coding therefor is expressed in a wide variety of mammalian tissues. The RPTP.gamma. protein or glycoprotein may be produced by recombinant means. Antibodies to the protein, methods for measuring the quantity of the protein, methods for screening compounds, such as drugs, which can bind to the protein and inhibit or stimulate their enzymatic activity, are provided.

Abstract: A novel expression cloning method is provided for the detection, identification and purification of target proteins capable of binding at least to a tryosine-phosphorylated domain of a eukaryotic tyrosine kinase using novel peptide probes comprising an amino acid sequence substantially corresponding to a portion of a tyrosine-phosphorylated domain of a tyrosine kinase. The probe has at least one phosphorlated tyrosine residue and may be detectably labeled. Also disclosed is a method for preparing the probes a method for mapping to a chormosome a gene encoding a protein capable of binding to tyrosine-phosphorylated domains of tyrosine kinases, and a method for purifiying such a protein with the probe. Non-limiting examples of novel proteins discovered using the above cloning method include GRB-1, GRB-2, GRB-3, GRB-4 and GRB-7, as well as nucleic acid encoding these proteins, and methods for detecting these proteins are also provided.