1VSY: Proteasome Activator Complex

Citation:
Abstract
The proteasome is an abundant protease that is critically important for numerous cellular pathways. Proteasomes are activated in vitro by three known classes of proteins/complexes, including Blm10/PA200. Here, we report a 3.4 A resolution crystal structure of a proteasome-Blm10 complex, which reveals that Blm10 surrounds the proteasome entry pore in the 1.2 MDa complex to form a largely closed dome that is expected to restrict access of potential substrates. This architecture and the observation that Blm10 induces a disordered proteasome gate structure challenge the assumption that Blm10 functions as an activator of proteolysis in vivo. The Blm10 C terminus binds in the same manner as seen for 11S activators and inferred for 19S/PAN activators and indicates a unified model for gate opening. We also demonstrate that Blm10 acts to maintain mitochondrial function. Consistent with the structural data, the C-terminal residues of Blm10 are needed for this activity.
MMDB ID: 99518
PDB Deposition Date: 2010/1/5
Updated in MMDB: 2012/08
Experimental Method:
x-ray diffraction
Resolution: 3  Å
Source Organism:
Similar Structures:
Merged PDB IDs:1VSY 3L5Q
Asymmetric Unit for 1VSY: 68-meric
Molecular Components in 1VSY
Label Count Molecule
Proteins (68 molecules)
4
Proteasome Component C7-alpha
Molecule annotation
4
Proteasome Component Y7
Molecule annotation
4
Proteasome Component Y13
Molecule annotation
4
Proteasome Component Pre6
Molecule annotation
4
Proteasome Component Pup2
Molecule annotation
4
Proteasome Component Pre5
Molecule annotation
4
Proteasome Component C1
Molecule annotation
4
Proteasome Component Pre3
Molecule annotation
4
Proteasome Component Pup1
Molecule annotation
4
Proteasome Component Pup3
Molecule annotation
4
Proteasome Component C11
Molecule annotation
4
Proteasome Component Pre2
Molecule annotation
4
Proteasome Component C5
Molecule annotation
4
Proteasome Component Pre4
Molecule annotation
12
Proteasome Activator Blm10
Molecule annotation
* Click molecule labels to explore molecular sequence information.

Citing MMDB
.