Novel human phosphatase inhibitor protein

Abstract

The present invention provides a novel human phosphatase inhibitor protein (HPIP) and polynucleotides which identify and encode HPIP. The invention also provides genetically engineered expression vectors and host cells comprising the nucleic acid sequences encoding HPIP and a method for producing HPIP. The invention also provides for agonists, antibodies, or antagonists specifically binding HPIP, and their use, in the prevention and treatment of diseases associated with expression of HPIP. Additionally, the invention provides for the use of antisense molecules to polynucleotides encoding HPIP for the treatment of diseases associated with the expression of HPIP. The invention also provides diagnostic assays which utilize the polynucleotide, or fragments or the complement thereof, and antibodies specifically binding HPIP.

What is claimed is:  
     
         1 . A substantially purified human phosphatase inhibitor protein (HPIP) comprising the amino acid sequence of SEQ ID NO:1 or fragments thereof.  
     
     
         2 . An isolated and purified polynucleotide sequence encoding the HPIP of  claim 1 .  
     
     
         3 . A polynucleotide sequence which hybridizes under stringent conditions to the polynucleotide sequence of  claim 2 .  
     
     
         4 . A hybridization probe comprising the polynucleotide sequence of  claim 2 .  
     
     
         5 . An isolated and purified polynucleotide sequence comprising SEQ ID NO:2 or variants thereof.  
     
     
         6 . A polynucleotide sequence which is complementary to SEQ ID NO:2 or variants thereof.  
     
     
         7 . A hybridization probe comprising the polynucleotide sequence of  claim 6 .  
     
     
         8 . An expression vector containing the polynucleotide sequence of  claim 2 .  
     
     
         9 . A host cell containing the vector of  claim 8 .  
     
     
         10 . A method for producing a polypeptide comprising the amino acid sequence of SEQ ID NO:1 the method comprising the steps of: 
 a) culturing the host cell of  claim 9  under conditions suitable for the expression of the polypeptide; and    b) recovering the polypeptide from the host cell culture.    
     
     
         11 . A pharmaceutical composition comprising a substantially purified HPIP having an amino acid sequence of SEQ ID NO:1 in conjunction with a suitable pharmaceutical carrier.  
     
     
         12 . A purified antibody which binds specifically to the polypeptide of  claim 1 .  
     
     
         13 . A purified agonist which specifically binds to and modulates the activity of the polypeptide of  claim 1 .  
     
     
         14 . A purified antagonist which specifically binds to and modulates the activity of the polypeptide of  claim 1 .  
     
     
         15 . A method for treating diseases resulting from excessive cell growth and division comprising administering to a subject in need of such treatment an effective amount of the agonist of  claim 13 .  
     
     
         16 . A method for treating diseases resulting from insufficient cell growth and division comprising administering to a subject in need of such treatment an effective amount of the antagonist of  claim 14 .  
     
     
         17 . A method for detection of polynucleotides encoding HPIP in a biological sample comprising the steps of: 
 a) hybridizing a polynucleotide consisting of the polynucleotide of  claim 6  to nucleic acid material of a biological sample, thereby forming a hybridization complex; and    b) detecting said hybridization complex, wherein the presence of said complex correlates with the presence of a polynucleotide encoding HPIP in said biological sample.    
     
     
         18 . The method of  claim 17  wherein before hybridization, the nucleic acid material of the biological sample is amplified by the polymerase chain reaction.  
     
     
         19 . A method for treating a disease or condition associated with decreased expression of functional HPIP, comprising administering to a patient in need of such treatment the composition of  claim 17 .  
     
     
         20 . A method of 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.    
     
     
         21 . A composition comprising an agonist compound identified by a method of  claim 20  and a pharmaceutically acceptable excipient.  
     
     
         22 . A method for treating a disease or condition associated with decreased expression of functional HPIP, comprising administering to a patient in need of such treatment a composition of  claim 21 .  
     
     
         23 . A method of 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.    
     
     
         24 . A composition comprising an antagonist compound identified by a method of  claim 23  and a pharmaceutically acceptable excipient.  
     
     
         25 . A method for treating a disease or condition associated with overexpression of functional HPIP, comprising administering to a patient in need of such treatment a composition of  claim 24 .  
     
     
         26 . A method of screening for a compound that specifically binds to the polypeptide of  claim 1 , the method comprising: 
 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 .    
     
     
         27 . A method of screening for a compound that modulates the activity of the polypeptide of  claim 1 , the method comprising: 
 a) combining the polypeptide of  claim 1  with at least one test compound under conditions permissive for the activity of the polypeptide of  claim 1 ,    b) assessing the activity of the polypeptide of  claim 1  in the presence of the test compound, and    c) comparing the activity of the polypeptide of  claim 1  in the presence of the test compound with the activity of the polypeptide of  claim 1  in the absence of the test compound, wherein a change in the activity of the polypeptide of  claim 1  in the presence of the test compound is indicative of a compound that modulates the activity of the polypeptide of  claim 1 .    
     
     
         28 . A method of screening a compound for effectiveness in altering expression of a target polynucleotide, wherein said target polynucleotide comprises a sequence of  claim 5 , 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.    
     
     
         29 . A method of assessing toxicity of a test compound, the 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 12  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 12  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.    
     
     
         30 . A diagnostic test for a condition or disease associated with the expression of HPIP in a biological sample, the method comprising: 
 a) combining the biological sample with an antibody of  claim 11 , 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.    
     
     
         31 . The antibody of  claim 11 , 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.    
     
     
         32 . A composition comprising an antibody of  claim 11  and an acceptable excipient.  
     
     
         33 . A method of diagnosing a condition or disease associated with the expression of HPIP in a subject, comprising administering to said subject an effective amount of the composition of  claim 32 .  
     
     
         34 . A composition of  claim 32 , wherein the antibody is labeled.  
     
     
         35 . A method of diagnosing a condition or disease associated with the expression of HPIP in a subject, comprising administering to said subject an effective amount of the composition of  claim 34 .  
     
     
         36 . A method of preparing a polyclonal antibody with the specificity of the antibody of  claim 11 , the method comprising: 
 a) immunizing an animal with a polypeptide having the 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 the amino acid sequence of SEQ ID NO:1.    
     
     
         37 . A polyclonal antibody produced by a method of  claim 36 .  
     
     
         38 . A composition comprising the polyclonal antibody of  claim 37  and a suitable carrier.  
     
     
         39 . A method of making a monoclonal antibody with the specificity of the antibody of  claim 11 , the method comprising: 
 a) immunizing an animal with a polypeptide having the 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 the amino acid sequence of SEQ ID NO:1.    
     
     
         40 . A monoclonal antibody produced by a method of  claim 39 .  
     
     
         41 . A composition comprising the monoclonal antibody of  claim 40  and a suitable carrier.  
     
     
         42 . The antibody of  claim 11 , wherein the antibody is produced by screening a Fab expression library.  
     
     
         43 . The antibody of  claim 11 , wherein the antibody is produced by screening a recombinant immunoglobulin library.  
     
     
         44 . A method of detecting a polypeptide having the amino acid sequence of SEQ ID NO:1 in a sample, the method comprising: 
 a) incubating the antibody of  claim 11  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 the amino acid sequence of SEQ ID NO:1 in the sample.    
     
     
         45 . A method of purifying a polypeptide having the amino acid sequence of SEQ ID NO:1 from a sample, the method comprising: 
 a) incubating the antibody of  claim 11  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 the amino acid sequence of SEQ ID NO:1.    
     
     
         46 . A microarray wherein at least one element of the microarray is a polynucleotide of  claim 13 .  
     
     
         47 . A method of generating a transcript image of a sample which contains polynucleotides, the method comprising: 
 a) labeling the polynucleotides of the sample,    b) contacting the elements of the microarray of  claim 46  with the labeled polynucleotides of the sample under conditions suitable for the formation of a hybridization complex, and    c) quantifying the expression of the polynucleotides in the sample.    
     
     
         48 . An array comprising different nucleotide molecules affixed in distinct physical locations on a solid substrate, wherein at least one of said nucleotide molecules comprises a first oligonucleotide or polynucleotide sequence specifically hybridizable with at least 30 contiguous nucleotides of a target polynucleotide, and wherein said target polynucleotide is a polynucleotide of  claim 12 .  
     
     
         49 . An array of  claim 48 , wherein said first oligonucleotide or polynucleotide sequence is completely complementary to at least 30 contiguous nucleotides of said target polynucleotide.  
     
     
         50 . An array of  claim 48 , wherein said first oligonucleotide or polynucleotide sequence is completely complementary to at least 60 contiguous nucleotides of said target polynucleotide.  
     
     
         51 . An array of  claim 48 , wherein said first oligonucleotide or polynucleotide sequence is completely complementary to said target polynucleotide.  
     
     
         52 . An array of  claim 48 , which is a microarray.  
     
     
         53 . An array of  claim 48 , further comprising said target polynucleotide hybridized to a nucleotide molecule comprising said first oligonucleotide or polynucleotide sequence.  
     
     
         54 . An array of  claim 48 , wherein a linker joins at least one of said nucleotide molecules to said solid substrate.  
     
     
         55 . An array of  claim 48 , wherein each distinct physical location on the substrate contains multiple nucleotide molecules, and the multiple nucleotide molecules at any single distinct physical location have the same sequence, and each distinct physical location on the substrate contains nucleotide molecules having a sequence which differs from the sequence of nucleotide molecules at another distinct physical location on the substrate.  
     
     
         56 . A polypeptide of  claim 1 , comprising the amino acid sequence of SEQ ID NO:1.  
     
     
         57 . A polynucleotide of  claim 12 , comprising the polynucleotide sequence of SEQ ID NO:2.