Cargando…

ATP binding to neighbouring subunits and intersubunit allosteric coupling underlie proteasomal ATPase function

The primary functions of the proteasome are driven by a highly allosteric ATPase complex. ATP binding to only two subunits in this hexameric complex triggers substrate binding, ATPase–20S association and 20S gate opening. However, it is unclear how ATP binding and hydrolysis spatially and temporally...

Descripción completa

Detalles Bibliográficos
Autores principales: Kim, Young-Chan, Snoberger, Aaron, Schupp, Jane, Smith, David M.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Nature Pub. Group 2015
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4608255/
https://www.ncbi.nlm.nih.gov/pubmed/26465836
http://dx.doi.org/10.1038/ncomms9520
_version_ 1782395638303948800
author Kim, Young-Chan
Snoberger, Aaron
Schupp, Jane
Smith, David M.
author_facet Kim, Young-Chan
Snoberger, Aaron
Schupp, Jane
Smith, David M.
author_sort Kim, Young-Chan
collection PubMed
description The primary functions of the proteasome are driven by a highly allosteric ATPase complex. ATP binding to only two subunits in this hexameric complex triggers substrate binding, ATPase–20S association and 20S gate opening. However, it is unclear how ATP binding and hydrolysis spatially and temporally coordinates these allosteric effects to drive substrate translocation into the 20S. Here, we use FRET to show that the proteasomal ATPases from eukaryotes (RPTs) and archaea (PAN) bind ATP with high affinity at neighbouring subunits, which complements the well-established spiral-staircase topology of the 26S ATPases. We further show that two conserved arginine fingers in PAN located at the subunit interface work together as a single allosteric unit to mediate the allosteric effects of ATP binding, without altering the nucleotide-binding pattern. Rapid kinetics analysis also shows that ring resetting of a sequential hydrolysis mechanism can be explained by thermodynamic equilibrium binding of ATP. These data support a model whereby these two functionally distinct allosteric networks cooperate to translocate polypeptides into the 20S for degradation.
format Online
Article
Text
id pubmed-4608255
institution National Center for Biotechnology Information
language English
publishDate 2015
publisher Nature Pub. Group
record_format MEDLINE/PubMed
spelling pubmed-46082552015-11-25 ATP binding to neighbouring subunits and intersubunit allosteric coupling underlie proteasomal ATPase function Kim, Young-Chan Snoberger, Aaron Schupp, Jane Smith, David M. Nat Commun Article The primary functions of the proteasome are driven by a highly allosteric ATPase complex. ATP binding to only two subunits in this hexameric complex triggers substrate binding, ATPase–20S association and 20S gate opening. However, it is unclear how ATP binding and hydrolysis spatially and temporally coordinates these allosteric effects to drive substrate translocation into the 20S. Here, we use FRET to show that the proteasomal ATPases from eukaryotes (RPTs) and archaea (PAN) bind ATP with high affinity at neighbouring subunits, which complements the well-established spiral-staircase topology of the 26S ATPases. We further show that two conserved arginine fingers in PAN located at the subunit interface work together as a single allosteric unit to mediate the allosteric effects of ATP binding, without altering the nucleotide-binding pattern. Rapid kinetics analysis also shows that ring resetting of a sequential hydrolysis mechanism can be explained by thermodynamic equilibrium binding of ATP. These data support a model whereby these two functionally distinct allosteric networks cooperate to translocate polypeptides into the 20S for degradation. Nature Pub. Group 2015-10-14 /pmc/articles/PMC4608255/ /pubmed/26465836 http://dx.doi.org/10.1038/ncomms9520 Text en Copyright © 2015, Nature Publishing Group, a division of Macmillan Publishers Limited. All Rights Reserved. http://creativecommons.org/licenses/by/4.0/ This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/
spellingShingle Article
Kim, Young-Chan
Snoberger, Aaron
Schupp, Jane
Smith, David M.
ATP binding to neighbouring subunits and intersubunit allosteric coupling underlie proteasomal ATPase function
title ATP binding to neighbouring subunits and intersubunit allosteric coupling underlie proteasomal ATPase function
title_full ATP binding to neighbouring subunits and intersubunit allosteric coupling underlie proteasomal ATPase function
title_fullStr ATP binding to neighbouring subunits and intersubunit allosteric coupling underlie proteasomal ATPase function
title_full_unstemmed ATP binding to neighbouring subunits and intersubunit allosteric coupling underlie proteasomal ATPase function
title_short ATP binding to neighbouring subunits and intersubunit allosteric coupling underlie proteasomal ATPase function
title_sort atp binding to neighbouring subunits and intersubunit allosteric coupling underlie proteasomal atpase function
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4608255/
https://www.ncbi.nlm.nih.gov/pubmed/26465836
http://dx.doi.org/10.1038/ncomms9520
work_keys_str_mv AT kimyoungchan atpbindingtoneighbouringsubunitsandintersubunitallostericcouplingunderlieproteasomalatpasefunction
AT snobergeraaron atpbindingtoneighbouringsubunitsandintersubunitallostericcouplingunderlieproteasomalatpasefunction
AT schuppjane atpbindingtoneighbouringsubunitsandintersubunitallostericcouplingunderlieproteasomalatpasefunction
AT smithdavidm atpbindingtoneighbouringsubunitsandintersubunitallostericcouplingunderlieproteasomalatpasefunction