Human glutathione peroxidase-6

Abstract

The invention provides a human glutathione peroxidase (GPx6) and polynucleotides which identify and encode GPx6. The invention also provides expression vectors, host cells, antibodies, agonists, and antagonists. The invention also provides methods for diagnosing, treating or preventing disorders associated with expression of GPx6.

What is claimed is:  
     
         1 . An isolated polypeptide comprising an amino acid sequence selected from the group consisting of: 
 a) an amino acid sequence of SEQ ID NO: 1,    b) a naturally occurring amino acid sequence having at least 90% sequence identity to an amino acid sequence of SEQ ID NO: 1,    c) a biologically active fragment of an amino acid sequence of SEQ ID NO: 1, and    d) an immunogenic fragment of an amino acid sequence of SEQ ID NO: 1.    
     
     
         2 . An isolated polypeptide of  claim 1  consisting of the amino acid sequence of SEQ ID NO: 1.  
     
     
         3 . An isolated polynucleotide encoding a polypeptide of  claim 1 .  
     
     
         4 . An isolated polynucleotide of  claim 3  consisting of the nucleic acid sequence of SEQ ID NO: 2.  
     
     
         5 . A recombinant polynucleotide comprising a promoter sequence operably linked to a polynucleotide of  claim 3 .  
     
     
         6 . A cell transformed with a recombinant polynucleotide of  claim 5 .  
     
     
         7 . A method for producing a polypeptide of  claim 1 , the method comprising: 
 a) culturing a cell under conditions suitable for expression of the polypeptide, wherein said cell is transformed with a recombinant polynucleotide, and said recombinant polynucleotide comprises a promoter sequence operably linked to a polynucleotide encoding the polypeptide of  claim 1 , and    b) recovering the polypeptide so expressed.    
     
     
         8 . An isolated antibody which specifically binds to a polypeptide of  claim 1 .  
     
     
         9 . An isolated polynucleotide comprising a polynucleotide sequence selected from the group consisting of: 
 a) a polynucleotide sequence of SEQ ID NO: 2,    b) a naturally occurring polynucleotide sequence having at least 90% sequence identity to a polynucleotide sequence of SEQ ID NO: 2,    c) a polynucleotide sequence complementary to a),    d) a polynucleotide sequence complementary to b), and    e) an RNA equivalent of a)-d).    
     
     
         10 . An isolated polynucleotide of  claim 9  comprising the polynucleotide sequence of SEQ ID NO: 2.  
     
     
         11 . An isolated polynucleotide comprising at least 60 contiguous nucleotides of a polynucleotide of  claim 9 .  
     
     
         12 . A method for detecting a target polynucleotide in a sample, said target polynucleotide having a sequence of a polynucleotide of  claim 9 , the method comprising: 
 a) hybridizing the sample with a probe comprising at least 20 contiguous nucleotides comprising a sequence complementary to said target polynucleotide in the sample, and which probe specifically hybridizes to said target polynucleotide, under conditions whereby a hybridization complex is formed between said probe and said target polynucleotide or fragments thereof, and    b) detecting the presence or absence of said hybridization complex, and, optionally, if present, the amount thereof.    
     
     
         13 . A method of  claim 12 , wherein the probe comprises at least 60 contiguous nucleotides.  
     
     
         14 . A method for detecting a target polynucleotide in a sample, said target polynucleotide having a sequence of a polynucleotide of  claim 9 , the method comprising: 
 a) amplifying said target polynucleotide or fragment thereof using polymerase chain reaction amplification, and    b) detecting the presence or absence of said amplified target polynucleotide or fragment thereof, and, optionally, if present, the amount thereof.    
     
     
         15 . A method for screening a compound for effectiveness as an agonist of a polypeptide of  claim 1 , the method comprising: 
 a) exposing a sample comprising a polypeptide of  claim 1  to a compound, and    b) detecting agonist activity in the sample.    
     
     
         16 . A composition comprising an agonist compound identified by a method of  claim 15  and a pharmaceutically acceptable excipient.  
     
     
         17 . A method for screening a compound for effectiveness as an antagonist of a polypeptide of  claim 1 , the method comprising: 
 a) exposing a sample comprising a polypeptide of  claim 1  to a compound, and    b) detecting antagonist activity in the sample.    
     
     
         18 . A composition comprising an antagonist compound identified by a method of  claim 17  and a pharmaceutically acceptable excipient.  
     
     
         19 . A method of screening for a compound that specifically binds to the polypeptide of  claim 1 , said method comprising the steps of: 
 a) combining the polypeptide of  claim 1  with at least one test compound under suitable conditions, and    b) detecting binding of the polypeptide of  claim 1  to the test compound, thereby identifying a compound that specifically binds to the polypeptide of  claim 1 .    
     
     
         20 . A method for screening a compound for effectiveness in altering expression of a target polynucleotide, wherein said target polynucleotide comprises a sequence of  claim 4 , the method comprising: 
 a) exposing a sample comprising the target polynucleotide to a compound, under conditions suitable for the expression of the target polynucleotide,    b) detecting altered expression of the target polynucleotide, and    c) comparing the expression of the target polynucleotide in the presence of varying amounts of the compound and in the absence of the compound.    
     
     
         21 . A method for assessing toxicity of a test compound, said method comprising: 
 a) treating a biological sample containing nucleic acids with the test compound;    b) hybridizing the nucleic acids of the treated biological sample with a probe comprising at least 20 contiguous nucleotides of a polynucleotide of  claim 9  under conditions whereby a specific hybridization complex is formed between said probe and a target polynucleotide in the biological sample, said target polynucleotide comprising a polynucleotide sequence of a polynucleotide of  claim 9  or fragment thereof;    c) quantifying the amount of hybridization complex; and    d) comparing the amount of hybridization complex in the treated biological sample with the amount of hybridization complex in an untreated biological sample, wherein a difference in the amount of hybridization complex in the treated biological sample is indicative of toxicity of the test compound.    
     
     
         22 . A diagnostic test for a condition or disease associated with the expression of GPx6 in a biological sample comprising the steps of: 
 a) combining the biological sample with an antibody of  claim 8 , under conditions suitable for the antibody to bind the polypeptide and form an antibody:polypeptide complex; and    b) detecting the complex, wherein the presence of the complex correlates with the presence of the polypeptide in the biological sample.    
     
     
         23 . The antibody of  claim 8 , wherein the antibody is: 
 a) a chimeric antibody,    b) a single chain antibody,    c) a Fab fragment,    d) a F(ab′) 2  fragment, or    e) a humanized antibody.    
     
     
         24 . A composition comprising an antibody of  claim 8  and an acceptable excipient.  
     
     
         25 . A method of diagnosing a condition or disease associated with the expression of GPx6 in a subject, comprising administering to said subject an effective amount of the composition of  claim 24 .  
     
     
         26 . A composition of  claim 24 , wherein the antibody is labeled.  
     
     
         27 . A method of diagnosing a condition or disease associated with the expression of GPx6 in a subject, comprising administering to said subject an effective amount of the composition of  claim 26 .  
     
     
         28 . A method of preparing a polyclonal antibody with the specificity of the antibody of  claim 8  comprising: 
 a) immunizing an animal with a polypeptide having an amino acid sequence of SEQ ID NO: 1, or an immunogenic fragment thereof, under conditions to elicit an antibody response;  
 b) isolating antibodies from said animal; and  
 c) screening the isolated antibodies with the polypeptide, thereby identifying a polyclonal antibody which binds specifically to a polypeptide having an amino acid sequence of SEQ ID NO: 1.  
 
     
     
         29 . An antibody produced by a method of  claim 28 .  
     
     
         30 . A composition comprising the antibody of  claim 29  and a suitable carrier.  
     
     
         31 . A method of making a monoclonal antibody with the specificity of the antibody of  claim 8  comprising: 
 a) immunizing an animal with a polypeptide having an amino acid sequence of SEQ ID NO: 1, or an immunogenic fragment thereof, under conditions to elicit an antibody response;  
 b) isolating antibody producing cells from the animal;  
 c) fusing the antibody producing cells with immortalized cells to form monoclonal antibody-producing hybridoma cells;  
 d) culturing the hybridoma cells; and  
 e) isolating from the culture monoclonal antibody which binds specifically to a polypeptide having an amino acid sequence of SEQ ID NO: 1.  
 
     
     
         32 . A monoclonal antibody produced by a method of  claim 31 .  
     
     
         33 . A composition comprising the antibody of  claim 32  and a suitable carrier.  
     
     
         34 . The antibody of  claim 8 , wherein the antibody is produced by screening a Fab expression library.  
     
     
         35 . The antibody of  claim 8 , wherein the antibody is produced by screening a recombinant immunoglobulin library.  
     
     
         36 . A method for detecting a polypeptide having an amino acid sequence of SEQ ID NO: 1 in a sample, comprising the steps of: 
 a) incubating the antibody of  claim 8  with a sample under conditions to allow specific binding of the antibody and the polypeptide; and    b) detecting specific binding, wherein specific binding indicates the presence of a polypeptide having an amino acid sequence of SEQ ID NO: 1 in the sample.    
     
     
         37 . A method of purifying a polypeptide having an amino acid sequence of SEQ ID NO: 1 from a sample, the method comprising: 
 a) incubating the antibody of  claim 8  with a sample under conditions to allow specific binding of the antibody and the polypeptide; and    b) separating the antibody from the sample and obtaining the purified polypeptide having an amino acid sequence of SEQ ID NO: 1.