Proteasome structure

Leggett, D. S., et ah. Multiple associated proteins regulate proteasome structure and function. Mol Cell, 2002, lOfJJ, 495-507. 

Walz, j. et al. 26S proteasome structure revealed by three-dimensional electron microscopy. J Struct Biol 1998, 121, 19-29. 

Waiz, j., Erdmann, A., Kania, M., Typke, D., Koster, A. J., and Baumeister, W. 26S proteasome structure revealed by three-dimensional electron microscopy. J Struct Biol 1998, 323, 19-29. 

Rivett A], Mason GG Murray, RZ Reidlinger J (1997) Regulation of proteasome structure and function. Mol Biol Rep 24 99-102 Rivett AJ, Palmer A, Knecht E (1992) Electron microscopic localization of the multi-catalytic proteinase complex in rat liver and in cultured cells.) Histochem Cyto-chem 40 1165-1172... 

Kajava, A. V., Gorbea, C., Ortega, J., Rechsteiner, M., and Steven, A. C. (2004). New HEAT-like repeat motifs in proteins regulating proteasome structure and function. Trends Biochem. Sci. (in press). 

Proteasomes - Both 20S and 26S proteasomes are known. Figure 28.44 shows the structure of the yeast 20S proteasome. Structurally, the proteasome shows remarkable similarity to the GroEL chaperonin (see here). Both are multitiered cylinders with 7-fold symmetry. Both can accept an unfolded polypeptide chain in their hollow interior. But whereas GroEL protects the polypeptide chain, the proteasome degrades it. 

Fig. 9 (continued) assignments of correlations from the complex are not available, (b) Residues whose resonances are affected by the IIS interaction are mapped on the proteasome structure, (c) Crystal structure of the llS-proteasome complex, (d) The intensities of resonances during the titration are used to obtain an approximate dissociation constant (irD = 12 10 pM) for the IIS interaction that is consistent with the core particle titration data (see insets). The decrease in intensity of one of the correlations from L81 is shown on the left and the concomitant increase in a bound peak on the right. Errors are quantified from signal-to-noise in spectra. [Ligand] and [Protein] refer to total ligand and protein concentrations. Adapted from [3] with permission... 

Robust decreases in the expression of the various proteasome subunits and ubiquitin-conjugating enzymes have been described in prefrontal cortex in schizophrenia. Neuronal ubiquitin and proteasomes play an important role in the assembly, function and plasticity of the synapse. Structural proteins including tubulin and a-spectrin also show decreased expression in prefrontal cortex. 

Kessel, M. et al. Homology in structural organization between E. coli ClpAP protease the eukaryotic 26 S proteasome. J Mol Biol 1995, 250, 587-594. 

Haetmann-Peteesen, R., Tanaka, K., and Hendil, K. B. Quaternary structure of the ATPase complex of human 26 S proteasomes determined by chemical cross-linking. Arch Biochem Biophys 2001, 386, 89-94. 

Kajava, a. V. What curves alpha-solenoids Fvidence for an alpha-helical toroid structure of Rpnl and Rpn2 proteins of the 26 S proteasome. J Biol Chem 2002, 277, 49791-8. 

Mueller, T. D. and Fbigon, J. Structural determinants for the binding of ubiquitin-like domains to the proteasome. Embo J 2003, 22, 4634-45. 

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