UBC4/YBR082C Summary Help

Standard Name UBC4 1
Systematic Name YBR082C
Feature Type ORF, Verified
Description Ubiquitin-conjugating enzyme (E2); key E2 partner with Ubc1p for the anaphase-promoting complex (APC); mediates degradation of abnormal or excess proteins, including calmodulin and histone H3; regulates levels of DNA Polymerase-{alpha} to promote efficient and accurate DNA replication; interacts with many SCF ubiquitin protein ligases; component of the cellular stress response; UBC4 has a paralog, UBC5, that arose from the whole genome duplication (1, 2, 3, 4, 5, 6, 7, 8 and see Summary Paragraph)
Name Description UBiquitin-Conjugating 1
Chromosomal Location
ChrII:407169 to 406628 | ORF Map | GBrowse
Note: this feature is encoded on the Crick strand.
Gene Ontology Annotations All UBC4 GO evidence and references
  View Computational GO annotations for UBC4
Molecular Function
Manually curated
Biological Process
Manually curated
Cellular Component
Manually curated
Regulators 21 genes
Classical genetics
Large-scale survey
426 total interaction(s) for 262 unique genes/features.
Physical Interactions
  • Affinity Capture-MS: 12
  • Affinity Capture-RNA: 6
  • Affinity Capture-Western: 17
  • Biochemical Activity: 10
  • Co-crystal Structure: 1
  • Co-purification: 2
  • Protein-RNA: 1
  • Reconstituted Complex: 47
  • Two-hybrid: 7

Genetic Interactions
  • Dosage Rescue: 3
  • Negative Genetic: 181
  • Phenotypic Enhancement: 26
  • Phenotypic Suppression: 4
  • Positive Genetic: 56
  • Synthetic Growth Defect: 29
  • Synthetic Lethality: 16
  • Synthetic Rescue: 8

Expression Summary
Length (a.a.) 148
Molecular Weight (Da) 16,456
Isoelectric Point (pI) 6.5
Phosphorylation PhosphoGRID | PhosphoPep Database
sequence information
ChrII:407169 to 406628 | ORF Map | GBrowse
Note: this feature is encoded on the Crick strand.
Last Update Coordinates: 2011-02-03 | Sequence: 1997-01-28
Subfeature details
Most Recent Updates
Coordinates Sequence
CDS 1..47 407169..407123 2011-02-03 1997-01-28
Intron 48..142 407122..407028 2011-02-03 1997-01-28
CDS 143..542 407027..406628 2011-02-03 1997-01-28
Retrieve sequences
Analyze Sequence
S288C only
S288C vs. other species
S288C vs. other strains
External Links All Associated Seq | E.C. | Entrez Gene | Entrez RefSeq Protein | MIPS | Search all NCBI (Entrez) | UniProtKB
Primary SGDIDS000000286

UBC4 encodes a ubiquitin conjugating enzyme that links ubiquitin (Ubi4p) to lysine residues of target proteins (1, 9). This function may be performed in conjunction with an E3, ubiquitin-protein ligase. Ubc4p interacts with the ubiquitin ligase E3-CaM in ubiquitinating calmodulin (Cmd1p) (2) and also interacts with several SCF ubiquitin ligase complexes in vitro (4). Ubc4p plays a role in both protein polyubiquitination (1) and protein monoubiquitination (2), and is also a central component of the cellular stress response (3). Indeed, expression of Ubc4p is heat-inducible and its interaction with the proteasome complex is strongly induced by heat stress (10). UBC4 is also involved in sporulation (9). A related ubiquitin conjugating enzyme, (UBC5), shows strong sequence similarity to UBC4 and both are complementary in function (1). Together, Ubc4p and Ubc5p mediate the selective degradation of short-lived and abnormal proteins. Loss of UBC4 and UBC5 results in cell growth defects, temperature sensitivity, inviability in the presence of an amino acid analog, and the induction of the stress response (1).

Last updated: 2005-05-24 Contact SGD

References cited on this page View Complete Literature Guide for UBC4
1) Seufert W and Jentsch S  (1990) Ubiquitin-conjugating enzymes UBC4 and UBC5 mediate selective degradation of short-lived and abnormal proteins. EMBO J 9(2):543-50
2) Parag HA, et al.  (1993) Selective ubiquitination of calmodulin by UBC4 and a putative ubiquitin protein ligase (E3) from Saccharomyces cerevisiae. FEBS Lett 325(3):242-6
3) Seufert W and Jentsch S  (1991) Yeast ubiquitin-conjugating enzymes involved in selective protein degradation are essential for cell viability. Acta Biol Hung 42(1-3):27-37
4) Kus BM, et al.  (2004) Functional interaction of 13 yeast SCF complexes with a set of yeast E2 enzymes in vitro. Proteins 54(3):455-67
5) Byrne KP and Wolfe KH  (2005) The Yeast Gene Order Browser: combining curated homology and syntenic context reveals gene fate in polyploid species. Genome Res 15(10):1456-61
6) Rodrigo-Brenni MC and Morgan DO  (2007) Sequential E2s Drive Polyubiquitin Chain Assembly on APC Targets. Cell 130(1):127-39
7) Singh RK, et al.  (2009) Histone levels are regulated by phosphorylation and ubiquitylation-dependent proteolysis. Nat Cell Biol 11(8):925-33
8) Haworth J, et al.  (2010) Ubc4 and Not4 Regulate Steady-State Levels of DNA Polymerase-{alpha} to Promote Efficient and Accurate DNA Replication. Mol Biol Cell 21(18):3205-19
9) Hochstrasser M  (1996) Ubiquitin-dependent protein degradation. Annu Rev Genet 30:405-39
10) Tongaonkar P, et al.  (2000) Evidence for an interaction between ubiquitin-conjugating enzymes and the 26S proteasome. Mol Cell Biol 20(13):4691-8