Evidence map›Paper›PMID 16055722›Full record

ArticleMolecular and cellular biology2005

A family of mammalian E3 ubiquitin ligases that contain the UBR box motif and recognize N-degrons.

Takafumi Tasaki, Lubbertus C F Mulder, Akihiro Iwamatsu, Min Jae Lee, Ilia V Davydov, Alexander Varshavsky, Mark Muesing, Yong Tae Kwon

Open access · greenAbstract read
In one paragraph

Article in Molecular and cellular biology, 2005. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 211 papers.

0numbers the graph read from it
0cells of the map it votes in
211citing papers in PubMed
6.3field-weighted citation impact, top 3% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

211 citing papers in PubMed, 362 citations in OpenAlex.

  1. Article
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  7. Function and regulation of the mitochondrial stress response.Nature structural & molecular biology · 2026
    Review
  8. Article
  9. Article
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  11. Article
  12. Article
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  15. Tumor-promoting UBR4 coordinates impaired mitophagy-associated senescence and lung adenocarcinoma pathogenesis.Proceedings of the National Academy of Sciences of the United States of America · 2025
    Article
  16. Article
  17. Article
  18. Review
  19. Revisiting the structure of UBR box from human UBR6.Protein science : a publication of the Protein Society · 2025
    Article
  20. Review

151 more citing papers are in PubMed but not listed here.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

8 authors at 4 institutions in 1 country.

Takafumi TasakiCenter for Pharmacogenetics and Department of Pharmaceutical Sciences, University of Pittsburgh, PA 15261, USA.
Lubbertus C F Mulder
Akihiro Iwamatsu
Min Jae Lee
Ilia V Davydov
Alexander Varshavsky
Mark Muesing
Yong Tae Kwon
University of Pittsburgh · USCalifornia Institute of Technology · USAaron Diamond AIDS Research Center · USRockefeller University · US

Funding

The Functions, Mechanisms, and Regulation of N-Terminal ArginylationR01GM031530 · NIGMS · MASSACHUSETTS INSTITUTE OF TECHNOLOGY · PI ALEXANDER J VARSHAVSKY · 1985 to 2026
$14.5M
Ubiquitin Ligases, Mechanisms and Functions of the N-End Rule PathwayR01DK039520 · NIDDK · MASSACHUSETTS INSTITUTE OF TECHNOLOGY · PI VARSHAVSKY, ALEXANDER J · 1988 to 2025
$10.0M
MECHANICS AND FUNCTIONS OF THE N-END RULE PATHWAYR37DK039520 · NIDDK · CALIFORNIA INSTITUTE OF TECHNOLOGY · PI VARSHAVSKY, ALEXANDER J · 1998 to 2007
$4.4M
A GENETIC ANALYSIS OF HIV-1 INTEGRATIONR01AI047054 · NIAID · AARON DIAMOND AIDS RESEARCH CENTER · PI MUESING, MARK AYER · 2000 to 2004
$1.9M
Function and Mechanisms of the N-End Rule PathwayR01GM069482 · NIGMS · UNIVERSITY OF PITTSBURGH AT PITTSBURGH · PI KWON, YONG TAE · 2003 to 2007
$1.5M
Host factors impact in early phases of HIV-1 infectionR21AI056987 · NIAID · AARON DIAMOND AIDS RESEARCH CENTER · PI MULDER, LUBBERTUS C · 2004 to 2005
$513k
Ubiquitin Ligases, Mechanisms and Functions of the N-End Rule PathwayR56DK039520 · NIDDK · CALIFORNIA INSTITUTE OF TECHNOLOGY · PI VARSHAVSKY, ALEXANDER J · 2008 to 2008
$161k
NIAID NIH HHS AI056987NIAID NIH HHS AI47054NIAID NIH HHS R01 AI047054NIAID NIH HHS R21 AI056987NIDDK NIH HHS DK39520NIDDK NIH HHS R01 DK039520NIDDK NIH HHS R37 DK039520NIDDK NIH HHS R56 DK039520NIGMS NIH HHS GM31530NIGMS NIH HHS GM69482NIGMS NIH HHS R01 GM031530NIGMS NIH HHS R01 GM069482
6 · The paper itself

Abstract

A subset of proteins targeted by the N-end rule pathway bear degradation signals called N-degrons, whose determinants include destabilizing N-terminal residues. Our previous work identified mouse UBR1 and UBR2 as E3 ubiquitin ligases that recognize N-degrons. Such E3s are called N-recognins. We report here that while double-mutant UBR1(-/-) UBR2(-/-) mice die as early embryos, the rescued UBR1(-/-) UBR2(-/-) fibroblasts still retain the N-end rule pathway, albeit of lower activity than that of wild-type fibroblasts. An affinity assay for proteins that bind to destabilizing N-terminal residues has identified, in addition to UBR1 and UBR2, a huge (570 kDa) mouse protein, termed UBR4, and also the 300-kDa UBR5, a previously characterized mammalian E3 known as EDD/hHYD. UBR1, UBR2, UBR4, and UBR5 shared a approximately 70-amino-acid zinc finger-like domain termed the UBR box. The mammalian genome encodes at least seven UBR box-containing proteins, which we propose to call UBR1 to UBR7. UBR1(-/-) UBR2(-/-) fibroblasts that have been made deficient in UBR4 as well (through RNA interference) were significantly impaired in the degradation of N-end rule substrates such as the Sindbis virus RNA polymerase nsP4 (bearing N-terminal Tyr) and the human immunodeficiency virus type 1 integrase (bearing N-terminal Phe). Our results establish the UBR box family as a unique class of E3 proteins that recognize N-degrons or structurally related determinants for ubiquitin-dependent proteolysis and perhaps other processes as well.

Indexed as

Amino Acid MotifsAmino Acid SequenceAnimalsBlotting, NorthernCalmodulin-Binding ProteinsCells, CulturedDNADNA, ComplementaryDNA-Directed RNA PolymerasesFibroblastsGenotypeHIV IntegraseKineticsLentivirusMass SpectrometryMiceCalmodulin-Binding ProteinsDNADNA, ComplementaryDNA-Directed RNA PolymerasesHIV IntegraseMicrotubule-Associated ProteinsPeptidesProteasome Endopeptidase ComplexUbiquitin-Protein LigasesUBR1 protein, humanUBR2 protein, humanUbr4 protein, mouse

Identifiers

PMID16055722
PMCPMC1190250
OpenAlexW2097350262

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.