Intragenic deletion in the gene encoding ubiquitin carboxy-terminal hydrolase in gad mice


The gracile axonal dystrophy (gad) mouse is an autosomal recessive mutant that shows sensory ataxia at an early stage, followed by motor ataxia at a later stage1. Pathologically, the mutant is characterized by 'dying-back' type axonal degeneration and formation of spheroid bodies in nerve terminals2,3,4,5. Recent pathological observations have associated brain ageing and neurodegenerative diseases with progressive accumulation of ubiquitinated protein conjugates6,7. In gad mice, accumulation of amyloid β-protein and ubiquitin-positive deposits occur retrogradely along the sensory and motor nervous systems8,9. We previously reported that the gad mutation was transmitted by a gene on chromosome 5 (refs 10,11). Here we find that the gad mutation is caused by an in-frame deletion including exons 7 and 8 of Uchl1, encoding the ubiquitin carboxy-terminal hydrolase (UCH) isozyme (Uch-l1) selectively expressed in the nervous system and testis12,13,14,15. The gad allele encodes a truncated Uch-l1 lacking a segment of 42 amino acids containing a catalytic residue16. As Uch-l1 is thought to stimulate protein degradation by generating free monomeric ubiquitin16,17,18, the gad mutation appears to affect protein turnover. Our data suggest that altered function of the ubiquitin system directly causes neurodegeneration. The gad mouse provides a useful model for investigating human neurodegenerative disorders.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Figure 1: Analysis of Uchl1 expression in gad mice.
Figure 2: Genomic analysis of the mutated Uchl1 in gad mice.
Figure 3: Analysis of Uchl1 expression.
Figure 4: Immunostaining of ubiquitin (a,d), proteasome ( b,e) and Uch-l1 (c,f) in the gracile nucleus of medulla oblongata in wild-type (ac) and homozygous gad (df) mice at 12 weeks of age.

Accession codes




  1. 1

    Yamazaki, K. et al. Gracile axonal dystrophy (GAD), a new neurological mutant in the mouse. Proc. Soc. Exp. Biol. Med. 187, 209–215 (1988).

    CAS  Article  Google Scholar 

  2. 2

    Mukoyama, M., Yamazaki, K., Kikuchi, T. & Tomita, T. Neuropathology of gracile axonal dystrophy (GAD) mouse (an animal model of central axonopathy in primary sensory neurons). Acta Neuropathol. 79, 294–299 ( 1989).

    CAS  Article  Google Scholar 

  3. 3

    Kikuchi, T., Mukoyama, M., Yamazaki, K. & Moriya, H. Axonal degeneration of ascending sensory neurons in gracile axonal dystrophy mutant mouse. Acta Neuropathol. (Berl.) 80, 145–151 (1990).

    CAS  Article  Google Scholar 

  4. 4

    Oda, K., Yamazaki, K., Miura, H., Shibasaki, H. & Kikuchi, T. Dying back type axonal degeneration of sensory nerve terminals in muscle spindles of the gracile axonal dystrophy (GAD) mutant mouse. Neuropathol. Appl. Neurobiol. 18, 265–281 (1992).

    CAS  Article  Google Scholar 

  5. 5

    Miura, H. et al. Progressive degeneration of motor nerve terminals in GAD mutant mouse with hereditary sensory axonopathy. Neuropathol. Appl. Neurobiol. 19, 41–51 ( 1993).

    CAS  Article  Google Scholar 

  6. 6

    Arnold, J. et al. Ubiquitin and its role in neurodegeneration. Prog. Brain Res. 117, 23–34 (1998).

    CAS  Article  Google Scholar 

  7. 7

    Alves-Rodrigues, A., Gregori, L. & Figueiredo-Pereira, M.E. Ubiquitin, cellular inclusions and their role in neurodegeneration. Trends Neurosci. 21, 516–520 (1998).

    CAS  Article  Google Scholar 

  8. 8

    Ichihara, N. et al. Axonal degeneration promotes abnormal accumulation of amyloid β-protein in ascending gracile tract of gracile axonal dystrophy (GAD) mouse. Brain Res. 695, 173–178 (1995).

    CAS  Article  Google Scholar 

  9. 9

    Wu, J. et al. Abnormal ubiquitination of dystrophic axons in central nervous system of gracile axonal dystrophy (GAD) mutant mouse. Alzheimer's Res. 2, 163–168 ( 1996).

    Google Scholar 

  10. 10

    Yamazaki, K., Sakakibara, A., Tomita, T., Mukoyama, M. & Kikuchi, T. Location of gracile axonal dystrophy (gad) on chromosome 5 of the mouse. Jpn. J. Genet. 62, 479–484 (1987).

    Article  Google Scholar 

  11. 11

    Suh, J.G., Yamanishi, T., Matsui, K., Tanaka, K. & Wada, K. Mapping of the gracile axonal dystrophy (gad) gene to a region between D5Mit197 and D5Mit113 on proximal mouse chromosome 5. Genomics 27, 549– 551 (1995).

    CAS  Article  Google Scholar 

  12. 12

    Day, I.N.M. & Thompson, R.J. Molecular cloning of cDNA coding for human PGP 9.5 protein. A novel cytoplasmic marker for neurones and neuroendocrine cells. FEBS Lett. 210, 157– 160 (1987).

    CAS  Article  Google Scholar 

  13. 13

    Wilkinson, K.D. et al. The neuron-specific protein PGP 9.5 is a ubiquitin carboxyl-terminal hydrolase. Science 246, 670– 673 (1989).

    CAS  Article  Google Scholar 

  14. 14

    Day, I.N.M., Hinks, L.J. & Thompson, R.J. The structure of the human gene encoding protein gene product 9.5 (PGP9.5), a neuron-specific ubiquitin C-terminal hydrolase. Biochem. J. 268, 521–524 (1990).

    CAS  Article  Google Scholar 

  15. 15

    Kajimoto, Y. et al. cDNA cloning and tissue distribution of a rat ubiquitin carboxyl-terminal hydrolase PGP9.5. J. Biochem. 112, 28– 32 (1992).

    CAS  Article  Google Scholar 

  16. 16

    Larsen, C.N., Price, J.S. & Wilkinson, K.D. Substrate binding and catalysis by ubiquitin C-terminal hydrolases: Identification of two active site residues. Biochemistry 35, 6735–6744 ( 1996).

    CAS  Article  Google Scholar 

  17. 17

    Dang, L.C., Melandri, F.D. & Stein, R.S. Kinetic and mechanistic studies on the hydrolysis of ubiquitin C-terminal 7-amino-4-methylcoumarin by deubiquitinating enzymes. Biochemistry 37, 1868– 1879 (1998).

    CAS  Article  Google Scholar 

  18. 18

    Larsen, C.N., Krantz, B.A. & Wilkinson, K.D. Substrate specificity of deubiquitinating enzyme: ubiquitin C-terminal hydrolases. Biochemistry 37, 3358–3368 (1998).

    CAS  Article  Google Scholar 

  19. 19

    Dietrich, W.F. et al. A genetic map of the mouse with 4,006 simple sequence length polymorphism. Nature Genet. 7, 220– 245 (1994).

    CAS  Article  Google Scholar 

  20. 20

    Wakana, S., Shiroishi, T., Puschel, A.W. & Imai, K. The mouse semaphorin F (Semaf) maps to chromosome 15. Mamm. Genome 8, 698–699 ( 1997).

    CAS  Article  Google Scholar 

  21. 21

    Hershko, A. & Ciechanover, A. The ubiquitin system. Annu. Rev. Biochem. 67, 425–479 (1998).

    CAS  Article  Google Scholar 

  22. 22

    Mayer, A.N. & Wilkinson, K.D. Detection, resolution, and nomenclature of multiple ubiquitin carboxyl-terminal esterases from bovine calf thymus. Biochemistry 28, 166–172 (1989).

    CAS  Article  Google Scholar 

  23. 23

    Wilkinson, K.D., Deshpande, S. & Larsen, C.N. Comparisons of neuronal (PGP 9.5) and non-neuronal ubiquitin C-terminal hydrolases. Biochem. Soc. Trans. 20, 631–637 (1992).

    CAS  Article  Google Scholar 

  24. 24

    Ii, K., Ito, H., Tanaka, K. & Hirano, A. Immunocytochemical co-localization of the proteasome in ubiquitinated structures in neurodegenerative diseases and the elderly. J. Neuropathol. Exp. Neurol. 56, 125–131 (1997).

    CAS  Article  Google Scholar 

  25. 25

    Leroy, E. et al. The ubiquitin pathway in Parkinson's disease. Nature 395, 451–452 ( 1998).

    CAS  Article  Google Scholar 

  26. 26

    Ophoff, R.A., Terwindt, G.M., Frants, R.R. & Ferrari, M.D. P/Q-type Ca2+ channel defects in migraine, ataxia and epilepsy. Trends Pharmacol. Sci. 19, 121– 127 (1998).

    CAS  Article  Google Scholar 

  27. 27

    Lowe, J., McDermott, H., Landon, M., Mayer, R.J. & Wilkinson, K.D. Ubiquitin carboxyl-terminal hydrolase (PGP 9.5) is selectively present in ubiquitinated inclusion bodies characteristic of human neurodegenerative diseases. J. Pathol. 161, 153–160 ( 1990).

    CAS  Article  Google Scholar 

  28. 28

    Bizzi, A., Schaetzle, B., Patton, A., Gambetti, P. & Autilio-Gambetti, L. Axonal transport of two major components of the ubiquitin system: free ubiquitin and ubiquitin carboxyl-terminal hydrolase PGP 9.5. Brain Res. 548 292– 299 (1991).

    CAS  Article  Google Scholar 

  29. 29

    Wenthold, R.J., Yokotani, N., Doi, K. & Wada, K. Immunochemical characterization of the non-NMDA glutamate receptor using subunit-specific antibodies. J. Biol. Chem. 267, 501–507 (1992).

    CAS  PubMed  Google Scholar 

  30. 30

    Harada, T., Harada, C., Sekiguchi, M. & Wada, K. Light-induced retinal degeneration suppresses developmental progression of flip-to-flop alternative splicing in GluR1. J. Neurosci. 18, 3336–3343 (1998).

    CAS  Article  Google Scholar 

Download references


We thank Y. Hayashizaki, T. Tomita, K. Oda and K. Tanaka for helpful advice; R.S. Petralia for critical reading of our manuscript; T. Shiroishi for supplying M. m. molossinus; and M. Shikama for the breeding and care of animals. This work was supported in part by research grants from the Ministry of Education, Science, Sports and Culture, the Ministry of Health and Welfare, and the Science and Technology Agency of Japan.

Author information



Corresponding author

Correspondence to Keiji Wada.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Saigoh, K., Wang, YL., Suh, JG. et al. Intragenic deletion in the gene encoding ubiquitin carboxy-terminal hydrolase in gad mice. Nat Genet 23, 47–51 (1999).

Download citation

Further reading


Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing