Novel human Jak2 kinase

Abstract

The present invention provides a polynucleotide (hjak2) which identifies and encodes a novel human Jak2 kinase (HJAK2) which was expressed in the placenta. The present invention also provides for antisense molecules and oligomers designed from the nucleotide sequence or its antisense. The invention further provides genetically engineered expression vectors and host cells for the production of purified HJAK2 peptide, antibodies capable of binding to HJAK2, inhibitors which bind to HJAK2 and pharmaceutical compositions based on HJAK2 specific antibodies or inhibitors. The invention specifically provides for diagnostic assays based on altered hjak2 expression and which allow identification of such a condition. These assays utilize probes which comprise oligomers, fragments, or portions of hjak2 or its regulatory elements or antibodies specifically binding HJAK2.

1 . An antibody that specifically binds to a polypeptide comprising an amino acid sequence of SEQ ID NO:2.  
     
     
         2 . The antibody of  claim 1 , wherein the antibody is polyclonal.  
     
     
         3 . The antibody of  claim 1 , wherein the antibody is monoclonal.  
     
     
         4 . The antibody of  claim 1 , wherein the antibody is recombinant.  
     
     
         5 . The antibody of  claim 1 , wherein the antibody is chimeric.  
     
     
         6 . The antibody of  claim 1 , wherein the antibody is human.  
     
     
         7 . The antibody of  claim 1 , wherein the antibody has an affinity for the polypeptide of at least about 10 −9  M.  
     
     
         8 . The antibody of  claim 7 , wherein the antibody has an affinity for the polypeptide of at least about 10 −10  M.  
     
     
         9 . The antibody of  claim 8 , further comprising a reporter molecule.  
     
     
         10 . The antibody of  claim 14 , wherein the reporter molecule is selected from the group consisting of radionuclides, enzymes, fluorescent agents, chemiluinescent agents, and chromogenic agents.  
     
     
         11 . A pharmaceutical composition comprising the antibody of  claim 6  and a pharmaceutically acceptable excipient.  
     
     
         12 . A diagnostic composition comprising the antibody of  claim 6 .  
     
     
         13 . A method for detecting human JAK2 kinase in a sample, comprising: 
 (a) contacting the antibody of  claim 6  with the sample; and    (b) detecting specific binding of the antibody to a component of the sample.    
     
     
         14 . A polypeptide comprising an amino acid sequence of SEQ ID NO:2.  
     
     
         15 . The polypeptide of  claim 14 , further comprising a reporter molecule.  
     
     
         16 . The polypeptide of  claim 15 , wherein the reporter molecule is selected from the group consisting of radionuclides, enzymes, fluorescent agents, chemiluinescent agents, and chromogenic agents.  
     
     
         17 . The polypeptide of  claim 14 , further comprising a signal or leader sequence.  
     
     
         18 . A polypeptide comprising a variant amino acid sequence of SEQ ID NO:2, wherein the polypeptide has kinase activity and the variant amino acid sequence has an insertion, deletion, or substitution of about 1 to 5 amino acids as compared to SEQ ID NO:2.  
     
     
         19 . A polynucleotide encoding a polypeptide comprising an amino acid sequence of SEQ ID NO:2.  
     
     
         20 . The polynucleotide of  claim 19 , comprising a nucleic acid sequence of SEQ ID NO:1.