Differential roles of the COOH termini of AAA subunits of PA700 (19 S regulator) in asymmetric assembly and Activation of the 26 S proteasome

Thomas G. Gillette, Brajesh Kumar, David Thompson, Clive A. Slaughter, George N. DeMartino

Research output: Contribution to journalArticle

111 Citations (Scopus)

Abstract

The 26 S proteasome is an energy-dependent protease that degrades proteins modified with polyubiquitin chains. It is assembled from two multi-protein subcomplexes: a protease (20 S proteasome) and an ATPase regulatory complex (PA700 or 19 S regulatory particle) that contains six different AAA family subunits (Rpt1 to -6). Here we show that binding of PA700 to the 20 S proteasome is mediated by the COOH termini of two (Rpt2 and Rpt5) of the six Rpt subunits that constitute the interaction surface between the subcomplexes. COOH-terminal peptides of either Rpt2 or Rpt5 bind to the 20 S proteasome and activate hydrolysis of short peptide substrates. Simultaneous binding of both COOH-terminal peptides had additive effects on peptide substrate hydrolysis, suggesting that they bind to distinct sites on the proteasome. In contrast, only the Rpt5 peptide activated hydrolysis of protein substrates. Nevertheless, the COOH-terminal peptide of Rpt2 greatly enhanced this effect, suggesting that proteasome activation is a multistate process. Rpt2 and Rpt5 COOH-terminal peptides cross-linked to different but specific subunits of the 20 S proteasome. These results reveal critical roles of COOH termini of Rpt subunits of PA700 in the assembly and activation of eukaryotic 26 S proteasome. Moreover, they support a model in which Rpt subunits bind to dedicated sites on the proteasome and play specific, nonequivalent roles in the asymmetric assembly and activation of the 26 S proteasome.

Original languageEnglish (US)
Pages (from-to)31813-31822
Number of pages10
JournalJournal of Biological Chemistry
Volume283
Issue number46
DOIs
StatePublished - Nov 14 2008

Fingerprint

Proteasome Endopeptidase Complex
Chemical activation
Peptides
Hydrolysis
Substrates
Polyubiquitin
Proteins
Adenosine Triphosphatases

ASJC Scopus subject areas

  • Biochemistry
  • Cell Biology
  • Molecular Biology

Cite this

Differential roles of the COOH termini of AAA subunits of PA700 (19 S regulator) in asymmetric assembly and Activation of the 26 S proteasome. / Gillette, Thomas G.; Kumar, Brajesh; Thompson, David; Slaughter, Clive A.; DeMartino, George N.

In: Journal of Biological Chemistry, Vol. 283, No. 46, 14.11.2008, p. 31813-31822.

Research output: Contribution to journalArticle

@article{22b82c9e6c664c8d8f1483df0ca4ab18,
title = "Differential roles of the COOH termini of AAA subunits of PA700 (19 S regulator) in asymmetric assembly and Activation of the 26 S proteasome",
abstract = "The 26 S proteasome is an energy-dependent protease that degrades proteins modified with polyubiquitin chains. It is assembled from two multi-protein subcomplexes: a protease (20 S proteasome) and an ATPase regulatory complex (PA700 or 19 S regulatory particle) that contains six different AAA family subunits (Rpt1 to -6). Here we show that binding of PA700 to the 20 S proteasome is mediated by the COOH termini of two (Rpt2 and Rpt5) of the six Rpt subunits that constitute the interaction surface between the subcomplexes. COOH-terminal peptides of either Rpt2 or Rpt5 bind to the 20 S proteasome and activate hydrolysis of short peptide substrates. Simultaneous binding of both COOH-terminal peptides had additive effects on peptide substrate hydrolysis, suggesting that they bind to distinct sites on the proteasome. In contrast, only the Rpt5 peptide activated hydrolysis of protein substrates. Nevertheless, the COOH-terminal peptide of Rpt2 greatly enhanced this effect, suggesting that proteasome activation is a multistate process. Rpt2 and Rpt5 COOH-terminal peptides cross-linked to different but specific subunits of the 20 S proteasome. These results reveal critical roles of COOH termini of Rpt subunits of PA700 in the assembly and activation of eukaryotic 26 S proteasome. Moreover, they support a model in which Rpt subunits bind to dedicated sites on the proteasome and play specific, nonequivalent roles in the asymmetric assembly and activation of the 26 S proteasome.",
author = "Gillette, {Thomas G.} and Brajesh Kumar and David Thompson and Slaughter, {Clive A.} and DeMartino, {George N.}",
year = "2008",
month = "11",
day = "14",
doi = "10.1074/jbc.M805935200",
language = "English (US)",
volume = "283",
pages = "31813--31822",
journal = "Journal of Biological Chemistry",
issn = "0021-9258",
publisher = "American Society for Biochemistry and Molecular Biology Inc.",
number = "46",

}

TY - JOUR

T1 - Differential roles of the COOH termini of AAA subunits of PA700 (19 S regulator) in asymmetric assembly and Activation of the 26 S proteasome

AU - Gillette, Thomas G.

AU - Kumar, Brajesh

AU - Thompson, David

AU - Slaughter, Clive A.

AU - DeMartino, George N.

PY - 2008/11/14

Y1 - 2008/11/14

N2 - The 26 S proteasome is an energy-dependent protease that degrades proteins modified with polyubiquitin chains. It is assembled from two multi-protein subcomplexes: a protease (20 S proteasome) and an ATPase regulatory complex (PA700 or 19 S regulatory particle) that contains six different AAA family subunits (Rpt1 to -6). Here we show that binding of PA700 to the 20 S proteasome is mediated by the COOH termini of two (Rpt2 and Rpt5) of the six Rpt subunits that constitute the interaction surface between the subcomplexes. COOH-terminal peptides of either Rpt2 or Rpt5 bind to the 20 S proteasome and activate hydrolysis of short peptide substrates. Simultaneous binding of both COOH-terminal peptides had additive effects on peptide substrate hydrolysis, suggesting that they bind to distinct sites on the proteasome. In contrast, only the Rpt5 peptide activated hydrolysis of protein substrates. Nevertheless, the COOH-terminal peptide of Rpt2 greatly enhanced this effect, suggesting that proteasome activation is a multistate process. Rpt2 and Rpt5 COOH-terminal peptides cross-linked to different but specific subunits of the 20 S proteasome. These results reveal critical roles of COOH termini of Rpt subunits of PA700 in the assembly and activation of eukaryotic 26 S proteasome. Moreover, they support a model in which Rpt subunits bind to dedicated sites on the proteasome and play specific, nonequivalent roles in the asymmetric assembly and activation of the 26 S proteasome.

AB - The 26 S proteasome is an energy-dependent protease that degrades proteins modified with polyubiquitin chains. It is assembled from two multi-protein subcomplexes: a protease (20 S proteasome) and an ATPase regulatory complex (PA700 or 19 S regulatory particle) that contains six different AAA family subunits (Rpt1 to -6). Here we show that binding of PA700 to the 20 S proteasome is mediated by the COOH termini of two (Rpt2 and Rpt5) of the six Rpt subunits that constitute the interaction surface between the subcomplexes. COOH-terminal peptides of either Rpt2 or Rpt5 bind to the 20 S proteasome and activate hydrolysis of short peptide substrates. Simultaneous binding of both COOH-terminal peptides had additive effects on peptide substrate hydrolysis, suggesting that they bind to distinct sites on the proteasome. In contrast, only the Rpt5 peptide activated hydrolysis of protein substrates. Nevertheless, the COOH-terminal peptide of Rpt2 greatly enhanced this effect, suggesting that proteasome activation is a multistate process. Rpt2 and Rpt5 COOH-terminal peptides cross-linked to different but specific subunits of the 20 S proteasome. These results reveal critical roles of COOH termini of Rpt subunits of PA700 in the assembly and activation of eukaryotic 26 S proteasome. Moreover, they support a model in which Rpt subunits bind to dedicated sites on the proteasome and play specific, nonequivalent roles in the asymmetric assembly and activation of the 26 S proteasome.

UR - http://www.scopus.com/inward/record.url?scp=57649140340&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=57649140340&partnerID=8YFLogxK

U2 - 10.1074/jbc.M805935200

DO - 10.1074/jbc.M805935200

M3 - Article

VL - 283

SP - 31813

EP - 31822

JO - Journal of Biological Chemistry

JF - Journal of Biological Chemistry

SN - 0021-9258

IS - 46

ER -