The apoptosis inhibitor ARC undergoes ubiquitin-proteasomal-mediated degradation in response to death stimuli: Identification of a degradation-resistant mutant

Young Jae Nam, Kartik Mani, Lily Wu, Chang Fu Peng, John W. Calvert, Roger S Y Foo, Barath Krishnamurthy, Wenfeng Miao, Anthony W. Ashton, David J. Lefer, Richard N. Kitsis

Research output: Contribution to journalArticle

47 Citations (Scopus)

Abstract

Efficient induction of apoptosis requires not only the activation of death-promoting proteins but also the inactivation of inhibitors of cell death. ARC (apoptosis repressor with caspase recruitment domain) is an endogenous inhibitor of apoptosis that antagonizes both central apoptosis pathways. Despite its potent inhibition of cell death, cells that express abundant ARC eventually succumb. A possible explanation is that ARC protein levels decrease dramatically in response to death stimuli. The mechanisms that mediate decreases in ARC protein levels during apoptosis and whether these decreases initiate the subsequent cell death are not known. Here we show that endogenous ARC protein levels decrease in response to death stimuli in a variety of cell contexts as well as in a model of myocardial ischemia-reperfusion in intact mice. Decreases in ARC protein levels are not explained by alterations in the abundance of ARC transcripts. Rather, pulse-chase experiments show that decreases in steady state ARC protein levels during apoptosis result from marked destabilization of ARC protein. ARC protein destabilization, in turn, is mediated by the ubiquitin-proteasomal pathway, as mutation of ARC ubiquitin acceptor residues stabilizes ARC protein and preserves its steady state levels during apoptosis. In addition, this degradation-resistant ARC mutant exhibits improved cytoprotection. We conclude that decreases in ARC protein levels in response to death stimuli are mediated by increased ARC protein degradation via the ubiquitin-proteasomal pathway. Moreover, these data demonstrate that decreases in ARC protein levels are a trigger, and not merely a consequence, of the ensuing cell death.

Original languageEnglish (US)
Pages (from-to)5522-5528
Number of pages7
JournalJournal of Biological Chemistry
Volume282
Issue number8
DOIs
StatePublished - Feb 23 2007

Fingerprint

AIDS-Related Complex
Corrosion inhibitors
Ubiquitin
Apoptosis
Degradation
Proteins
Cell death
Cell Death
Caspases
Myocardial Reperfusion
Cytoprotection

ASJC Scopus subject areas

  • Biochemistry

Cite this

The apoptosis inhibitor ARC undergoes ubiquitin-proteasomal-mediated degradation in response to death stimuli : Identification of a degradation-resistant mutant. / Nam, Young Jae; Mani, Kartik; Wu, Lily; Peng, Chang Fu; Calvert, John W.; Foo, Roger S Y; Krishnamurthy, Barath; Miao, Wenfeng; Ashton, Anthony W.; Lefer, David J.; Kitsis, Richard N.

In: Journal of Biological Chemistry, Vol. 282, No. 8, 23.02.2007, p. 5522-5528.

Research output: Contribution to journalArticle

Nam, Young Jae ; Mani, Kartik ; Wu, Lily ; Peng, Chang Fu ; Calvert, John W. ; Foo, Roger S Y ; Krishnamurthy, Barath ; Miao, Wenfeng ; Ashton, Anthony W. ; Lefer, David J. ; Kitsis, Richard N. / The apoptosis inhibitor ARC undergoes ubiquitin-proteasomal-mediated degradation in response to death stimuli : Identification of a degradation-resistant mutant. In: Journal of Biological Chemistry. 2007 ; Vol. 282, No. 8. pp. 5522-5528.
@article{362ffcccaa9546c28a0adfcf22b18f3b,
title = "The apoptosis inhibitor ARC undergoes ubiquitin-proteasomal-mediated degradation in response to death stimuli: Identification of a degradation-resistant mutant",
abstract = "Efficient induction of apoptosis requires not only the activation of death-promoting proteins but also the inactivation of inhibitors of cell death. ARC (apoptosis repressor with caspase recruitment domain) is an endogenous inhibitor of apoptosis that antagonizes both central apoptosis pathways. Despite its potent inhibition of cell death, cells that express abundant ARC eventually succumb. A possible explanation is that ARC protein levels decrease dramatically in response to death stimuli. The mechanisms that mediate decreases in ARC protein levels during apoptosis and whether these decreases initiate the subsequent cell death are not known. Here we show that endogenous ARC protein levels decrease in response to death stimuli in a variety of cell contexts as well as in a model of myocardial ischemia-reperfusion in intact mice. Decreases in ARC protein levels are not explained by alterations in the abundance of ARC transcripts. Rather, pulse-chase experiments show that decreases in steady state ARC protein levels during apoptosis result from marked destabilization of ARC protein. ARC protein destabilization, in turn, is mediated by the ubiquitin-proteasomal pathway, as mutation of ARC ubiquitin acceptor residues stabilizes ARC protein and preserves its steady state levels during apoptosis. In addition, this degradation-resistant ARC mutant exhibits improved cytoprotection. We conclude that decreases in ARC protein levels in response to death stimuli are mediated by increased ARC protein degradation via the ubiquitin-proteasomal pathway. Moreover, these data demonstrate that decreases in ARC protein levels are a trigger, and not merely a consequence, of the ensuing cell death.",
author = "Nam, {Young Jae} and Kartik Mani and Lily Wu and Peng, {Chang Fu} and Calvert, {John W.} and Foo, {Roger S Y} and Barath Krishnamurthy and Wenfeng Miao and Ashton, {Anthony W.} and Lefer, {David J.} and Kitsis, {Richard N.}",
year = "2007",
month = "2",
day = "23",
doi = "10.1074/jbc.M609186200",
language = "English (US)",
volume = "282",
pages = "5522--5528",
journal = "Journal of Biological Chemistry",
issn = "0021-9258",
publisher = "American Society for Biochemistry and Molecular Biology Inc.",
number = "8",

}

TY - JOUR

T1 - The apoptosis inhibitor ARC undergoes ubiquitin-proteasomal-mediated degradation in response to death stimuli

T2 - Identification of a degradation-resistant mutant

AU - Nam, Young Jae

AU - Mani, Kartik

AU - Wu, Lily

AU - Peng, Chang Fu

AU - Calvert, John W.

AU - Foo, Roger S Y

AU - Krishnamurthy, Barath

AU - Miao, Wenfeng

AU - Ashton, Anthony W.

AU - Lefer, David J.

AU - Kitsis, Richard N.

PY - 2007/2/23

Y1 - 2007/2/23

N2 - Efficient induction of apoptosis requires not only the activation of death-promoting proteins but also the inactivation of inhibitors of cell death. ARC (apoptosis repressor with caspase recruitment domain) is an endogenous inhibitor of apoptosis that antagonizes both central apoptosis pathways. Despite its potent inhibition of cell death, cells that express abundant ARC eventually succumb. A possible explanation is that ARC protein levels decrease dramatically in response to death stimuli. The mechanisms that mediate decreases in ARC protein levels during apoptosis and whether these decreases initiate the subsequent cell death are not known. Here we show that endogenous ARC protein levels decrease in response to death stimuli in a variety of cell contexts as well as in a model of myocardial ischemia-reperfusion in intact mice. Decreases in ARC protein levels are not explained by alterations in the abundance of ARC transcripts. Rather, pulse-chase experiments show that decreases in steady state ARC protein levels during apoptosis result from marked destabilization of ARC protein. ARC protein destabilization, in turn, is mediated by the ubiquitin-proteasomal pathway, as mutation of ARC ubiquitin acceptor residues stabilizes ARC protein and preserves its steady state levels during apoptosis. In addition, this degradation-resistant ARC mutant exhibits improved cytoprotection. We conclude that decreases in ARC protein levels in response to death stimuli are mediated by increased ARC protein degradation via the ubiquitin-proteasomal pathway. Moreover, these data demonstrate that decreases in ARC protein levels are a trigger, and not merely a consequence, of the ensuing cell death.

AB - Efficient induction of apoptosis requires not only the activation of death-promoting proteins but also the inactivation of inhibitors of cell death. ARC (apoptosis repressor with caspase recruitment domain) is an endogenous inhibitor of apoptosis that antagonizes both central apoptosis pathways. Despite its potent inhibition of cell death, cells that express abundant ARC eventually succumb. A possible explanation is that ARC protein levels decrease dramatically in response to death stimuli. The mechanisms that mediate decreases in ARC protein levels during apoptosis and whether these decreases initiate the subsequent cell death are not known. Here we show that endogenous ARC protein levels decrease in response to death stimuli in a variety of cell contexts as well as in a model of myocardial ischemia-reperfusion in intact mice. Decreases in ARC protein levels are not explained by alterations in the abundance of ARC transcripts. Rather, pulse-chase experiments show that decreases in steady state ARC protein levels during apoptosis result from marked destabilization of ARC protein. ARC protein destabilization, in turn, is mediated by the ubiquitin-proteasomal pathway, as mutation of ARC ubiquitin acceptor residues stabilizes ARC protein and preserves its steady state levels during apoptosis. In addition, this degradation-resistant ARC mutant exhibits improved cytoprotection. We conclude that decreases in ARC protein levels in response to death stimuli are mediated by increased ARC protein degradation via the ubiquitin-proteasomal pathway. Moreover, these data demonstrate that decreases in ARC protein levels are a trigger, and not merely a consequence, of the ensuing cell death.

UR - http://www.scopus.com/inward/record.url?scp=34247094793&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=34247094793&partnerID=8YFLogxK

U2 - 10.1074/jbc.M609186200

DO - 10.1074/jbc.M609186200

M3 - Article

C2 - 17142452

AN - SCOPUS:34247094793

VL - 282

SP - 5522

EP - 5528

JO - Journal of Biological Chemistry

JF - Journal of Biological Chemistry

SN - 0021-9258

IS - 8

ER -