Publication Date:
2013-05-07
Description:
The proteasomal ATPase ring, comprising Rpt1-Rpt6, associates with the heptameric alpha-ring of the proteasome core particle (CP) in the mature proteasome, with the Rpt carboxy-terminal tails inserting into pockets of the alpha-ring. Rpt ring assembly is mediated by four chaperones, each binding a distinct Rpt subunit. Here we report that the base subassembly of the Saccharomyces cerevisiae proteasome, which includes the Rpt ring, forms a high-affinity complex with the CP. This complex is subject to active dissociation by the chaperones Hsm3, Nas6 and Rpn14. Chaperone-mediated dissociation was abrogated by a non-hydrolysable ATP analogue, indicating that chaperone action is coupled to nucleotide hydrolysis by the Rpt ring. Unexpectedly, synthetic Rpt tail peptides bound alpha-pockets with poor specificity, except for Rpt6, which uniquely bound the alpha2/alpha3-pocket. Although the Rpt6 tail is not visualized within an alpha-pocket in mature proteasomes, it inserts into the alpha2/alpha3-pocket in the base-CP complex and is important for complex formation. Thus, the Rpt-CP interface is reconfigured when the lid complex joins the nascent proteasome to form the mature holoenzyme.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3687086/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉 〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3687086/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Park, Soyeon -- Li, Xueming -- Kim, Ho Min -- Singh, Chingakham Ranjit -- Tian, Geng -- Hoyt, Martin A -- Lovell, Scott -- Battaile, Kevin P -- Zolkiewski, Michal -- Coffino, Philip -- Roelofs, Jeroen -- Cheng, Yifan -- Finley, Daniel -- 1S10RR026814-01/RR/NCRR NIH HHS/ -- 5P20RR017708/RR/NCRR NIH HHS/ -- 8 P20 GM103420/GM/NIGMS NIH HHS/ -- P20 GM103418/GM/NIGMS NIH HHS/ -- P20 RR016475/RR/NCRR NIH HHS/ -- P20 RR017708/RR/NCRR NIH HHS/ -- R01 GM082893/GM/NIGMS NIH HHS/ -- R01GM045335/GM/NIGMS NIH HHS/ -- R01GM082893/GM/NIGMS NIH HHS/ -- R37GM043601/GM/NIGMS NIH HHS/ -- S10 RR026814/RR/NCRR NIH HHS/ -- England -- Nature. 2013 May 23;497(7450):512-6. doi: 10.1038/nature12123. Epub 2013 May 5.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, Massachusetts 02115, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23644457" target="_blank"〉PubMed〈/a〉
Keywords:
Adenosine Triphosphatases/chemistry/genetics/metabolism
;
Adenosine Triphosphate/metabolism
;
Binding Sites
;
Carrier Proteins/metabolism
;
Cryoelectron Microscopy
;
Holoenzymes/chemistry/metabolism
;
Models, Molecular
;
Molecular Chaperones/*metabolism
;
Proteasome Endopeptidase Complex/*chemistry/genetics/*metabolism
;
Protein Conformation
;
Recombinant Fusion Proteins/chemistry/genetics/metabolism
;
Saccharomyces cerevisiae/enzymology/genetics/growth & development/*metabolism
;
Saccharomyces cerevisiae Proteins/chemistry/genetics/*metabolism
Print ISSN:
0028-0836
Electronic ISSN:
1476-4687
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
,
Natural Sciences in General
,
Physics
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