5DSV

Crystal structure of human proteasome alpha7 tetradecamer

Summary for 5DSV

• Entry DOI: 10.2210/pdb5dsv/pdb
• Descriptor: Proteasome subunit alpha type-3 (1 entity in total)
• Functional Keywords: proteasome, hydrolase
• Biological source: Homo sapiens (Human)
• Cellular location: Cytoplasm: P25788
• Total number of polymer chains: 14
• Total formula weight: 398569.53

Authors

Satoh, T.,Thammaporn, R.,Seetaha, S.,Kato, K. (deposition date: 2015-09-17, release date: 2015-12-02, Last modification date: 2024-11-20)

Primary citation

Ishii, K.,Noda, M.,Yagi, H.,Thammaporn, R.,Seetaha, S.,Satoh, T.,Kato, K.,Uchiyama, S.
Disassembly of the self-assembled, double-ring structure of proteasome alpha 7 homo-tetradecamer by alpha 6
Sci Rep, 5:18167-18167, 2015

PubMed Abstract: The 20S core particle of the eukaryotic proteasome is composed of two α- and two β-rings, each of which is a hetero-heptamer composed of seven homologous but distinct subunits. Although formation of the eukaryotic proteasome is a highly ordered process assisted by assembly chaperones, α7, an α-ring component, has the unique property of self-assembling into a homo-tetradecamer. We used biophysical methods to characterize the oligomeric states of this proteasome subunit and its interaction with α6, which makes direct contacts with α7 in the proteasome α-ring. We determined a crystal structure of the α7 tetradecamer, which has a double-ring structure. Sedimentation velocity analytical ultracentrifugation and mass spectrometric analysis under non-denaturing conditions revealed that α7 exclusively exists as homo-tetradecamer in solution and that its double-ring structure is disassembled upon the addition of α6, resulting in a 1:7 hetero-octameric α6-α7 complex. Our findings suggest that proteasome formation involves the disassembly of non-native oligomers, which are assembly intermediates.

PubMed: 26657688
DOI: 10.1038/srep18167

Experimental method

X-RAY DIFFRACTION (3.75 Å)