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1z7q

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Crystal structure of the 20s proteasome from yeast in complex with the proteasome activator PA26 from Trypanosome brucei at 3.2 angstroms resolution

Structural highlights

1z7q is a 20 chain structure with sequence from Saccharomyces cerevisiae. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 3.22Å
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

PSA1_YEAST The proteasome degrades poly-ubiquitinated proteins in the cytoplasm and in the nucleus. It is essential for the regulated turnover of proteins and for the removal of misfolded proteins. The proteasome is a multicatalytic proteinase complex that is characterized by its ability to cleave peptides with Arg, Phe, Tyr, Leu, and Glu adjacent to the leaving group at neutral or slightly basic pH. It has an ATP-dependent proteolytic activity.

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

Proteasomes are cylindrical structures that function in multiple cellular processes by degrading a wide variety of cytosolic and nuclear proteins. Substrate access and product release from the enclosed catalytic chamber occurs through axial pores that are opened by activator complexes. Here, we report high-resolution structures of wild-type and mutant archaeal proteasomes bound to the activator PA26. These structures support the proposal that an ordered open conformation is required for proteolysis and that its formation can be triggered by outward displacement of surrounding residues. The structures and associated biochemical assays reveal the mechanism of binding, which involves an interaction between the PA26 C terminus and a conserved lysine. Surprisingly, biochemical observations implicate an equivalent interaction for the unrelated ATP-dependent activators PAN and PA700.

The 1.9 A structure of a proteasome-11S activator complex and implications for proteasome-PAN/PA700 interactions.,Forster A, Masters EI, Whitby FG, Robinson H, Hill CP Mol Cell. 2005 May 27;18(5):589-99. PMID:15916965^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Forster A, Masters EI, Whitby FG, Robinson H, Hill CP. The 1.9 A structure of a proteasome-11S activator complex and implications for proteasome-PAN/PA700 interactions. Mol Cell. 2005 May 27;18(5):589-99. PMID:15916965 doi:http://dx.doi.org/10.1016/j.molcel.2005.04.016