Binding sites for phosphotyrosine binding domains
AssigneeThe Regents of the University of California
InventorsWilliam Michael Kavanaugh, Lewis T. Williams
Life of this patent
Estimating the term…
Abstract
The present invention generally provides peptides that comprise a recognition sequence motif for phosphotyrosine binding proteins. In particular, the present invention provides peptides which comprise a core sequence of amino acids, and analogs thereof, which are recognized and bound by the PTB (phosphotyrosine binding) domain. Also provided are methods of using the peptides of the invention in diagnostic, screening and therapeutic applications.
Claims19
A substantially pure peptide which is capable of binding a PTB phosphotyrosine binding domain, wherein the peptide is from 5 to about 21 amino acids in length, and comprises a core sequence of amino acids Asn-X3-X1-X2-X4 (SEQ ID NO:1);
- wherein X1 is selected from the group consisting of Tyr, phosphotyrosine or an analog thereof, Thr, Asp, Gln, Ala and Phe;
- X2 is selected from phosphotyrosine or an analog thereof, and Tyr, provided that at least one of X1 and X2 is phosphotyrosine, or an analog thereof;
- X3 is selected from the group consisting of Leu and Ala;
- and
- X4 is selected from the group consisting of Trp, Leu, Ser, Phe and Gln.
A substantially pure peptide which is capable of binding a PTB phosphotyrosine binding domain, wherein the peptide is from 21 to about 50 amino acids in length, and comprises a core sequence of amino acids selected from the group consisting of SEQ ID NOS:
- 8-45.
A substantially pure peptide which is capable of binding a PTB phosphotyrosine binding domain, wherein the peptide is from 21 to about 50 amino acids in length and which comprises a core sequence of amino acids selected from the group consisting of SEQ ID NOS:46-47.
A method of determining whether a test compound is an agonist or antagonist of a PTB phosphotyrosine binding domain/phosphorylated ligand interaction, comprising the steps of:
- incubating the test compound with a protein comprising a PTB phosphotyrosine binding domain and a peptide, which peptide is from about 21 to about 50 amino acid residues in length and which comprises a core amino acid sequence selected from SEQ ID NOS:8-47;
- and
- determining the amount of protein bound to the peptide during said incubating I step;
- and
- comparing the amount of protein bound to the peptide during said incubating step to an amount of protein bound to the peptide in the absence of the test compound,
- wherein a test compound is determined to be an agonist of a PTB phosphotyrosine binding domain/phosphorylated ligand interaction when there is an increase in the amount of protein bound to the peptide in the presence of the test compound,
- and a test compound is determined to be an antagonist of a PTB phosphotyrosine binding domain/phosphorylated ligand interaction when there is a decrease in the amount of protein bound to the peptide in the presence of the test compound.
Dependencies are inferred from the claim text.