ROLE OF p62 IN AGING-RELATED DISEASE

Abstract

The application discloses a role of p62 in aging-related disease, such as development of obesity, type 2 diabetes mellitus, non-alcoholic fatty liver, various tumors, increased male mortality, intracellular inclusion named sequestosome, and redox regulation. In particular the application discloses a method of detecting the formation of inclusion bodies in neurodegenerative diseases. The invention further relates to a method of screening for therapeutic agents that disperse the inclusions. Further, transgenic mice containing a mutation in the p62 gene and having a functionally disrupted p62 gene locus are also disclosed.

1 . A method of screening for a compound which inhibits p62/ubiquitin binding, comprising:
 (a) contacting a compound with a sample containing p62 and ubiquitin;   (b) determining level of p62 and ubiquitin binding under conditions in which p62 and ubiquitin normally specifically bind to each other;   (c) determining level of p62 and ubiquitin binding, in the presence of said compound; and   comparing the level of p62 and ubiquitin binding described in parts (a) and (b), wherein if said level is lower in (c) than in (b), then said compound is an inhibitor of p62 ubiquitin binding.   
     
     
         2 . A method of preventing binding between ubiquitin and p62, comprising:
 (a) generating a recombinant viral or plasmid vector comprising a DNA sequence encoding a ubiquitin binding fragment of p62 polypeptide operatively linked to a promoter; and   (b) administering the viral or plasmid vector to a patient in need thereof, such that expression of said DNA sequence within a brain results in binding between the ubiquitin binding fragment of p62 and ubiquitin.   
     
     
         3 . A method of detecting inclusion body, comprising:
 (a) contacting a labeled p62 polypeptide to a sample that is suspected of containing inclusion body; and   (b) assaying for the presence of the label, which indicates presence of the inclusion body.   
     
     
         4 . A transgenic mouse whose somatic and germ cells comprise a functionally disrupted p62 gene, wherein said disrupted gene is introduced into the mouse or an ancestor of the mouse at an embryonic stage, wherein if homozygous for the disrupted gene exhibits an aging related disorder. 
     
     
         5 . The transgenic mouse according to  claim 4 , wherein the aging related disorder is obesity, diabetes, liver cancer, fatty liver, Paget Disease of Bone, or early mortality for male. 
     
     
         6 . The transgenic mouse according to  claim 4 , wherein said disrupted p62 gene is disrupted by an integrated targeting construct. 
     
     
         7 . The transgenic mouse according to  claim 4 , which does not produce p62 protein. 
     
     
         8 . A mouse embryonic stem cell having a genome comprising a heterozygous or homozygous functionally disrupted p62 gene, wherein said embryonic stem cell is capable of becoming the transgenic mouse of  claim 4 . 
     
     
         9 . The mouse embryonic stem cell according to  claim 8 , wherein said disrupted p62 gene is disrupted by an integrated targeting construct. 
     
     
         10 . A mouse somatic cell having a genome comprising a heterozygous or homozygous functionally disrupted p62 gene, which is isolated from the transgenic mouse of  claim 4 . 
     
     
         11 . The mouse somatic cell according to  claim 10 , wherein said disrupted p62 gene is disrupted by an integrated targeting construct. 
     
     
         12 . A mouse somatic cell line comprising the cells according to  claim 10 . 
     
     
         13 . The mouse cell line comprising the cells according to  claim 11 . 
     
     
         14 . A method of screening for a compound that counters aging-related disorder or disease of a mammal, comprising:
 (a) administering a test compound to the transgenic mouse according to  claim 4 ;   (b) measuring the level of disorder after the compound is administered; and   (c) comparing the level of disorder measured in (b) with the level of disorder in a control p62 deficient mouse, wherein reduction in the level of aging-related disorder in (b) compared with the control indicates that the compound counters aging-related disorder.   
     
     
         15 . A method to assist in the diagnosis of aging-related disease in a mammalian subject, comprising the step of assaying for a mutation in the subject's gene encoding p62, wherein detection of the mutation is indicative that the subject is at risk for aging-related disease. 
     
     
         16 . The method of  claim 15 , wherein the aging-related disease is obesity, diabetes, liver cancer, fatty liver, Paget Disease of Bone, or early mortality for male. 
     
     
         17 . The method of  claim 15 , wherein the mutation is a single nucleotide polymorphism mutation. 
     
     
         18 . The method of  claim 15 , wherein the mutation is a functional disruption so that a functional p62 is not expressed. 
     
     
         19 . The method of  claim 15 , wherein the subject is an infant human. 
     
     
         20 . An array comprising p62 nucleic acid.