Increasing lifespan by modulation of wwp-1 and ubc-18

Abstract

Ubiquitin ligase wwp-1 and ubiquitin conjugating enzyme ubc-18 are identified in nematodes as mediators of dietary restriction induced longevity and therefore as targets for modulation of lifespan in animals. Methods of screening for compounds that modulate longevity by assaying wwp-1 ubiquitination pathway parameters are provided, as are related systems. In addition, methods of using wwp-1 and/or ubc-18 to modulate longevity or delay onset of age-related diseases are described.

1 . A method of screening for a modulator of longevity, the method comprising:
 providing a non-human animal, which animal exhibits artificially altered expression or activity of wwp-1 or a homolog thereof and/or of ubc-18 or a homolog thereof;   administering a test compound to the non-human animal; and   assaying a wwp-1 ubiquitination pathway parameter in the non-human animal, wherein a change in the wwp-1 ubiquitination pathway parameter indicates the test compound modulates longevity.   
     
     
         2 . The method of  claim 1 , wherein the non-human animal exhibits reduced expression or activity of wwp-1 or the homolog thereof and/or reduced expression or activity of ubc-18 or the homolog thereof. 
     
     
         3 . The method of  claim 1 , wherein the non-human animal expresses a dominant negative form of wwp-1 or the homolog thereof or a dominant negative form of ubc-18 or the homolog thereof. 
     
     
         4 . The method of  claim 1 , wherein the non-human animal overexpresses wwp-1 or the homolog thereof and/or ubc-18 or the homolog thereof. 
     
     
         5 . The method of  claim 1 , wherein the non-human animal expresses a fusion protein comprising GFP or a homolog thereof and either wwp-1 or a homolog thereof or ubc-18 or a homolog thereof. 
     
     
         6 . The method of  claim 1 , wherein the wwp-1 ubiquitination pathway parameter comprises lifespan; an activity or expression level of wwp-1 or the homolog thereof, ubc-18 or the homolog thereof, or pha-4 or a homolog thereof; post-translational modification state of wwp-1 or the homolog thereof or a substrate thereof; or level of autophagy. 
     
     
         7 . The method of  claim 1 , wherein the change in the wwp-1 ubiquitination pathway parameter comprises increased lifespan of the non-human animal; increased expression of wwp-1 or the homolog thereof, ubc-18 or the homolog thereof, or pha-4 or a homolog thereof; increased activity of wwp-1 or the homolog thereof, ubc-18 or the homolog thereof, or pha-4 or a homolog thereof; increased phosphorylation of wwp-1 or the homolog thereof; increased ubiquitination of the substrate of wwp-1 or the homolog thereof; or increased autophagy. 
     
     
         8 . The method of  claim 1 , wherein the non-human animal is a nematode. 
     
     
         9 . The method of  claim 8 , wherein the nematode is  C. elegans.    
     
     
         10 . The method of  claim 1 , wherein the non-human animal is an adult. 
     
     
         11 . (canceled) 
     
     
         12 . The method of  claim 1 , wherein the test compound is a small molecule, a polypeptide, an antibody, a nucleic acid, an antisense molecule, or a double-stranded RNA. 
     
     
         13 . The method of  claim 1 , further comprising subjecting the non-human animal to dietary restriction. 
     
     
         14 .- 19 . (canceled) 
     
     
         20 . A method of screening for a compound that modulates longevity, the method comprising:
 contacting a cell that exhibits artificially altered expression or activity of wwp-1 or a homolog thereof and/or of ubc-18 or a homolog thereof with a test agent; and   assaying a wwp-1 ubiquitination pathway parameter in the cell, wherein a change in the wwp-1 ubiquitination pathway parameter relative to a control sample without the test agent identifies the compound that modulates longevity.   
     
     
         21 . The method of  claim 20 , wherein the wwp-1 ubiquitination pathway parameter comprises an activity or expression level of wwp-1 or the homolog thereof, ubc-18 or the homolog thereof, or pha-4 or a homolog thereof; post-translational modification state of wwp-1 or the homolog thereof or a substrate thereof; or level of autophagy. 
     
     
         22 . The method of  claim 20 , wherein the change in the wwp-1 ubiquitination pathway parameter comprises increased expression of wwp-1 or the homolog thereof, ubc-18 or the homolog thereof, or pha-4 or a homolog thereof; increased activity of wwp-1 or the homolog thereof, ubc-18 or the homolog thereof, or pha-4 or a homolog thereof; increased phosphorylation of wwp-1 or the homolog thereof; increased ubiquitination of the substrate of wwp-1 or the homolog thereof; or increased autophagy. 
     
     
         23 . The method of  claim 20 , wherein the test agent comprises a small molecule, a polypeptide, an antibody, a nucleic acid, an antisense molecule, or a double-stranded RNA. 
     
     
         24 .- 35 . (canceled) 
     
     
         36 . A method for modulating longevity of an animal, the method comprising: modulating expression or activity of wwp-1 or a homolog thereof and/or of ubc-18 or a homolog thereof in the animal. 
     
     
         37 . The method of  claim 36 , wherein the method comprises increasing expression of wwp-1 or the homolog thereof in the animal. 
     
     
         38 . The method of  claim 36 , wherein the method comprises increasing activity of wwp-1 or the homolog thereof in the animal. 
     
     
         39 . The method of  claim 38 , wherein the method comprises increasing phosphorylation of wwp-1 or the homolog thereof in the animal. 
     
     
         40 . The method of  claim 36 , wherein the method comprises increasing expression or activity of ubc-18 or the homolog thereof in the animal. 
     
     
         41 . The method of  claim 36 , wherein the method comprises administering to the animal a longevity modulator that affects wwp-1 or the homolog thereof or ubc-18 or the homolog thereof. 
     
     
         42 . The method of  claim 41 , wherein the longevity modulator increases expression of wwp-1 or the homolog thereof. 
     
     
         43 . The method of  claim 41 , wherein the longevity modulator decreases expression or activity of a phosphatase that dephosphorylates wwp-1 or the homolog thereof, or wherein the longevity modulator increases expression or activity of a kinase that phosphorylates wwp-1 or the homolog thereof. 
     
     
         44 . The method of  claim 41 , further comprising subjecting the animal to dietary restriction. 
     
     
         45 . A method of delaying onset of an age-related disease in an animal, the method comprising: modulating expression or activity of wwp-1 or a homolog thereof and/or of ubc-18 or a homolog thereof in the animal. 
     
     
         46 . The method of  claim 45 , wherein the age-related disease is diabetes, a cardiovascular disease, or a neurodegenerative disease. 
     
     
         47 . The method of  claim 45 , wherein the method comprises administering to the animal a longevity modulator that affects wwp-1 or the homolog thereof or ubc-18 or the homolog thereof. 
     
     
         48 . The method of  claim 45 , further comprising subjecting the animal to dietary restriction. 
     
     
         49 . The modulator identified by the method of  claim 1 . 
     
     
         50 . A method of increasing longevity or delaying onset of an age-related disease in a subject, comprising administering to the subject a compound identified by the method of  claim 1 . 
     
     
         51 . The modulator identified by the method of  claim 20 .