NIMA interacting proteins

Abstract

A novel class of NIMA interacting proteins (PIN), exemplified by Pin1, is provided. Pin1 induces a G2 arrest and delays NIMA-induced mitosis when overexpressed, and triggers mitotic arrest and DNA fragmentation when depleted. Methods of identifying other Pin proteins and Pin-interacting proteins and identifying compositions which affect Pin activity or expression are also provided.

1 . A functional fragment of a Pin1 polypeptide, which Pin1 polypeptide consists of the amino acid sequence set forth in SEQ ID NO:2, wherein the functional fragment has peptidyl prolyl isomerase (PPIase) activity and/or NIMA-binding activity.  
     
     
         2 . The functional fragment of  claim 1 , wherein the functional fragment has PPIase activity and NIMA-binding activity.  
     
     
         3 . The functional fragment of  claim 1 , wherein the functional fragment has PPIase activity.  
     
     
         4 . The functional fragment of  claim 3 , wherein the functional fragment is at least 105 residues in length.  
     
     
         5 . The functional fragment of  claim 1 , wherein the functional fragment has NIMA-binding activity.  
     
     
         6 . The functional fragment of  claim 5 , wherein the functional fragment is at least 39 residues in length.  
     
     
         7 . A Pin1 polypeptide fragment consisting of a conservative variant of: 
 (a) residues 5-43 of SEQ ID NO:2; or    (b) a functional fragment of (a) having NIMA-binding activity;    wherein the conservative variant has NIMA-binding activity.    
     
     
         8 . The Pin1 polypeptide fragment of  claim 7 , wherein the conservative variant amino acid(s) occur at one or more of residues 5, 6, 9, 13-19, 21, 22, 25, 28, 30, 31, 33, 35, 36, and/or 38-43.  
     
     
         9 . The Pin1 polypeptide fragment of  claim 7 , wherein at least residues 7, 8, 10-12, 20, 23, 24, 26, 27, 29, 32, 34, and 37 of the conservative variant are the identical to the corresponding residue in SEQ ID NO:2.  
     
     
         10 . A Pin1 polypeptide consisting of a conservative variant of: 
 (a) residues 59-163 of SEQ ID NO:2; or    (b) a functional fragment of (a) having PPIase activity;    wherein the conservative variant has PPIase activity.    
     
     
         11 . The Pin1 polypeptide fragment of  claim 10 , wherein the conservative variant amino acid(s) occur at one or more of residues 63-82, 84-96, 98-102, 105, 109, 110, 112, 116, 118, 124, 126, 131-133, 135, 140, 143, 146, 148, 151, 153, 154, and/or 161-163.  
     
     
         12 . The functional fragment of  claim 10 , wherein residues 59-62, 83, 97, 103, 104, 106-108, 111, 113-115, 117, 119-123, 125, 127-130, 134, 136-139, 141, 142, 144, 145, 147, 149, 150, 152, and 155-160 of the conservative variant are the identical to the corresponding residue in SEQ ID NO:2.  
     
     
         13 . A functional fragment of a Pin1 polypeptide having a deletion of one or more of amino acid residues 1-58, wherein the functional fragment has PPIase activity, and wherein the Pin1 polypeptide consists of the amino acid sequence set forth in SEQ ID NO:2.  
     
     
         14 . A functional fragment of a Pin1 polypeptide having a deletion of one or more of amino acid residues 1-4 and/or 44-163, wherein the functional fragment has NIMA-binding activity, and wherein the Pin1 polypeptide consists of the amino acid sequence set forth in SEQ ID NO:2.  
     
     
         15 . An isolated Pin1 polypeptide consisting of an amino acid sequence as set forth in SEQ ID NO:2 with conservative variation at one or more of amino acid residues 1-6, 9, 13-20, 21, 22, 25, 28, 30, 31, 33, 35, 36, 38-58, 63-83, 84-97, 98-103, 105, 109, 110, 112, 116, 118, 124, 126, 131-133, 135, 140, 143, 146, 148, 151, 153-154, and/or 161-163, wherein the Pin1 polypeptide has NIMA-binding activity and/or PPIase activity.  
     
     
         16 . A functional fragment of the Pin1 polypeptide of  claim 15 , wherein the fragment has NIMA-binding activity and/or PPIase activity.  
     
     
         17 . The functional fragment of the Pin1 polypeptide of  claim 15 , wherein the fragment has NIMA-binding activity and PPIase activity.  
     
     
         18 . The functional fragment of  claim 15 , wherein the functional fragment has PPIase activity.  
     
     
         19 . The functional fragment of  claim 18 , wherein the functional fragment is at least 105 residues in length.  
     
     
         20 . The functional fragment of  claim 15 , wherein the functional fragment has NIMA-binding activity.  
     
     
         21 . The functional fragment of  claim 20 , wherein the functional fragment is at least 39 residues in length.  
     
     
         22 . An isolated polypeptide consisting of an amino acid sequence as set forth in SEQ ID NO:2 with conservative variation at one or more of amino acid residues 1-58, wherein the polypeptide has PPIase activity.  
     
     
         23 . An isolated polypeptide consisting of an amino acid sequence as set forth in SEQ ID NO:2 with conservative variation at one or more of amino acid residues 1-4 and/or 44-163, wherein the polypeptide has NIMA-binding activity.  
     
     
         24 . An isolated Pin1 polypeptide consisting of: 
 a WW domain consisting of amino acid residues 5-43 of SEQ ID NO:2, or a functional fragment thereof, wherein the WW domain or functional fragment thereof binds to NIMA; and    a PPIase domain having PPIase activity.    
     
     
         25 . An isolated Pin1 polypeptide consisting of: 
 a PPIase domain consisting of amino acid residues 59-163 of SEQ ID NO:2, or a functional fragment thereof, wherein the PPIase domain or functional fragment thereof has PPIase activity; and    a WW domain that binds to NIMA.