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. 1998 Oct 13;95(21):12504-9.
doi: 10.1073/pnas.95.21.12504.

Cleavage motifs of the yeast 20S proteasome beta subunits deduced from digests of enolase 1

A K Nussbaum  1 , T P Dick, W Keilholz, M Schirle, S Stevanović, K Dietz, W Heinemeyer, M Groll, D H Wolf, R Huber, H G Rammensee, H Schild
Affiliations

Cleavage motifs of the yeast 20S proteasome beta subunits deduced from digests of enolase 1

A K Nussbaum et al. Proc Natl Acad Sci U S A. .

Abstract

The 436-amino acid protein enolase 1 from yeast was degraded in vitro by purified wild-type and mutant yeast 20S proteasome particles. Analysis of the cleavage products at different times revealed a processive degradation mechanism and a length distribution of fragments ranging from 3 to 25 amino acids with an average length of 7 to 8 amino acids. Surprisingly, the average fragment length was very similar between wild-type and mutant 20S proteasomes with reduced numbers of active sites. This implies that the fragment length is not influenced by the distance between the active sites, as previously postulated. A detailed analysis of the cleavages also allowed the identification of certain amino acid characteristics in positions flanking the cleavage site that guide the selection of the P1 residues by the three active beta subunits. Because yeast and mammalian proteasomes are highly homologous, similar cleavage motifs might be used by mammalian proteasomes. Therefore, our data provide a basis for predicting proteasomal degradation products from which peptides are sampled by major histocompatibility complex class I molecules for presentation to cytotoxic T cells.

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Figures

Figure 1
Figure 1
Enolase 1 degradation by yeast wt 20S proteasomes. Percent values represent the degree of enolase degradation as determined by linear regression. (Bottom) Dotted line shows incubation of enolase without proteasome.
Figure 2
Figure 2
Digestion map generated from degradation of enolase 1 by yeast wt 20S proteasomes. Vertical lines, cleavage sites determined by Edman degradation and MS; solid bars, degradation products identified by Edman degradation and mass spectrometry; open bars, degradation products identified by Edman degradation. The C terminus is not yet confirmed by MS.
Figure 3
Figure 3
Digestion maps generated from degradation of enolase 1 by yeast mutant 20S proteasomes. The maps include all the degradation products of enolase 1 identified after digestion by β5/Pre2− (A) , β2/Pup1− (B), β2/Pup1−β1/Pre3− (C), β1/Pre3− (D) 20S proteasomes. Degradation products were identified by Edman degradation and MS. Symbols are as in Fig. 2.
Figure 4
Figure 4
Distribution of fragment lengths generated by wt and mutant proteasomes from enolase 1. For each proteasome only internal fragments with known C terminus derived from one single digestion were included.
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References

    1. Groll M, Ditzel L, Lowe J, Stock D, Bochtler M, Bartunik H D, Huber R. Nature (London) 1997;386:463–471. - PubMed
    1. Kisselev A F, Akopian T N, Goldberg A L. J Biol Chem. 1998;273:1982–1989. - PubMed
    1. Orlowski M, Michaud C. Biochemistry. 1989;28:9270–9278. - PubMed
    1. Cardozo C, Vinitsky A, Hidalgo M C, Michaud C, Orlowski M. Biochemistry. 1992;31:7373–7380. - PubMed
    1. Heinemeyer W, Fischer M, Krimmer T, Stachon U, Wolf D H. J Biol Chem. 1997;272:25200–25209. - PubMed

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