Novel notch-like polypeptides

A composition of matter comprising:

• a) an isolated polypeptide having notch-like activity selected from the group consisting of:
• 1) the amino acid sequence recited in SEQ ID NO:
• 2;
• 2) the mature form of the polypeptide whose sequence is recited in SEQ ID NO:
• 2 (SEQ ID NO:4);
• 3) active variants of the amino acid sequence of SEQ ID NO:
• 2, wherein any amino acid specified in the chosen sequence is non-conservatively substituted, provided that no more than 15% of the amino acid residues in the sequence are so changed;
• and 4) the active fragment, precursor, salt, or derivative of the amino acid sequences given in 1), 2), or 3);
• b) an isolated polypeptide that is a naturally occurring allelic variant of the sequence given by SEQ ID NO:
• 2 or SEQ ID NO:4;
• c) an isolated polypeptide that is a naturally occurring allelic variant of the sequence given by SEQ ID NO:
• 2 or SEQ ID NO:4, wherein the variant is the translation of a single nucleotide polymorphism;
• d) a polypeptide as set forth in a) or b) or c), wherein the polypeptide binds specifically an antibody or a binding protein generated against SEQ ID NO:
• 2 or SEQ ID NO:4 or a fragment thereof;
• e) a fusion protein comprising a polypeptide as set forth in a) or b) or c) or d);
• f) an antagonist of a polypeptide as set forth in a) or b) or c) or d), wherein said antagonist comprises an amino acid sequence resulting from the non-conservative substitution, the deletion or both the non-conservative substitution and deletion of one or more residues into the corresponding polypeptide;
• g) a ligand which binds specifically to a polypeptide a) or b) or c) or d);
• h) a polypeptide a) or b) or c) or d) or e), wherein said polypeptides are in the form of active conjugates or complexes with a molecule chosen amongst radioactive labels, fluorescent labels, biotin, or cytotoxic agents;
• i) a peptide mimetic designed on the sequence or the structure or the sequence and structure of a polypeptide as set forth in a) or b) or c) or d);
• j) an isolated nucleic acid encoding for an isolated polypeptide selected from the group consisting of:
• 1) polypeptides as set forth in a) or b) or c) or d);
• 2) a fusion protein comprising a polypeptide as set forth in a) or b) or c) or d);
• or
• 3) an antagonist of a polypeptide as set forth in a) or b) or c) or d), wherein said antagonist comprises an amino acid sequence resulting from the non-conservative substitution, the deletion or both the non-conservative substitution and deletion of one or more residues into the corresponding polypeptide;
• k) an isolated nucleic acid sequence consisting of SEQ ID NO:
• 1, or the complement of said DNA sequence;
• l) a purified nucleic acid which:
• 1) hybridizes under high stringency conditions;
• or
• 2) exhibits at least about 85% identity over a stretch of at least about 30 nucleotides with a nucleic acid selected from the group consisting of SEQ ID NO:
• 1, or a complement of said DNA sequence;
• m) a vector comprising a nucleic acid as set forth in j) or k) or l);
• n) a polypeptide encoded by the nucleic acid of j) or k) or l);
• o) a host cell comprising a vector or nucleic acid as set forth in j) or k) or l) or m);
• p) a transgenic animal cell comprising a vector or nucleic acid as set forth in j) or k) or l) or m) and having enhanced or reduced expression levels of a polypeptide as set forth in a) or b) or c) or d);
• q) a transgenic non-human animal that has been transformed to have enhanced or reduced expression levels of a polypeptide as set forth in a) or b) or c) or d);
• r) a compound that enhances the expression level of a polypeptide as set forth in a) or b) or c) or d) in a cell or animal;
• or
• s) a compound that reduces the expression level of a polypeptide as set forth in a) or b) or c) or d) in a cell or animal.

A method for determining the activity and/or the presence of a notch-like polypeptide in a sample comprising:

• a) providing a protein-containing sample;
• b) contacting said sample with a ligand that specifically binds to a polypeptide comprising:
• 1) an isolated polypeptide having notch-like activity selected from the group consisting of:
• i) the amino acid sequence recited in SEQ ID NO:
• 2;
• ii) the mature form of the polypeptide whose sequence is recited in SEQ ID NO:
• 2 (SEQ ID NO:4);
• iii) active variants of the amino acid sequence of SEQ ID NO:
• 2, wherein any amino acid specified in the chosen sequence is non-conservatively substituted, provided that no more than 15% of the amino acid residues in the sequence are so changed;
• and iv) the active fragment, precursor, salt, or derivative of the amino acid sequences given in i), ii), or iii);
• 2) an isolated polypeptide that is a naturally occurring allelic variant of the sequence given by SEQ ID NO:
• 2 or SEQ ID NO:4;
• 3) an isolated polypeptide that is a naturally occurring allelic variant of the sequence given by SEQ ID NO:
• 2 or SEQ ID NO:4, wherein the variant is the translation of a single nucleotide polymorphism;
• or
• 4) a polypeptide as set forth in a) or b) or c), wherein the polypeptide binds specifically an antibody or a binding protein generated against SEQ ID NO:
• 2 or SEQ ID NO:4 or a fragment thereof;
• and
• c) determining the presence or said ligand bound to said polypeptide.