RAD6/YGL058W Summary Help

Standard Name RAD6
Systematic Name YGL058W
Alias UBC2 1 , PSO8 2
Feature Type ORF, Verified
Description Ubiquitin-conjugating enzyme (E2); involved in postreplication repair as a heterodimer with Rad18p, DSBR and checkpoint control as a heterodimer with Bre1p, ubiquitin-mediated N-end rule protein degradation as a heterodimer with Ubr1p, as well as endoplasmic reticulum-associated protein degradation (ERAD) with Ubr1p in the absence of canonical ER membrane ligases (1, 3, 4, 5, 6 and see Summary Paragraph)
Name Description RADiation sensitive
Chromosomal Location
ChrVII:393986 to 394504 | ORF Map | GBrowse
Genetic position: -44 cM
Gene Ontology Annotations All RAD6 GO evidence and references
  View Computational GO annotations for RAD6
Molecular Function
Manually curated
Biological Process
Manually curated
Cellular Component
Manually curated
Regulators 4 genes
Classical genetics
reduction of function
Large-scale survey
602 total interaction(s) for 362 unique genes/features.
Physical Interactions
  • Affinity Capture-MS: 16
  • Affinity Capture-RNA: 3
  • Affinity Capture-Western: 20
  • Biochemical Activity: 10
  • Co-localization: 2
  • Co-purification: 1
  • Far Western: 3
  • Reconstituted Complex: 9
  • Two-hybrid: 9

Genetic Interactions
  • Dosage Rescue: 2
  • Negative Genetic: 81
  • Phenotypic Enhancement: 29
  • Phenotypic Suppression: 2
  • Positive Genetic: 13
  • Synthetic Growth Defect: 234
  • Synthetic Haploinsufficiency: 1
  • Synthetic Lethality: 138
  • Synthetic Rescue: 29

Expression Summary
Length (a.a.) 172
Molecular Weight (Da) 19,705
Isoelectric Point (pI) 4.02
Phosphorylation PhosphoGRID | PhosphoPep Database
sequence information
ChrVII:393986 to 394504 | ORF Map | GBrowse
Genetic position: -44 cM
Last Update Coordinates: 2011-02-03 | Sequence: 1996-07-31
Subfeature details
Most Recent Updates
Coordinates Sequence
CDS 1..519 393986..394504 2011-02-03 1996-07-31
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 SGDIDS000003026

RAD6 encodes an E2 ubiquitin-conjugating enzyme required for postreplicational DNA repair, transcriptional activation and repression, protein degradation, and sporulation (1 and reviewed in 7). Rad6p interacts with various E3 ubiquitin ligases, such as Rad18p, Bre1p, and Ubr1p, that recruit Rad6p to the appropriate target protein during repair, transcription, and degradation, respectively (8, 9, 10). In its role in post-replication repair, a process often referred to as the RAD6 pathway, Rad6p promotes replication through DNA lesions located at stalled replication forks. Among the other proteins in the RAD6 epistasis group are RAD18, RAD5, MMS2, UBC13, POL30, REV1, REV3, REV7, and SRS2 (reviewed in 7 and 11).

Rad6p and Rad18p form a stable heterodimer that binds single-stranded DNA and possesses single-stranded DNA-dependent ATPase activity. (8). Upon DNA damage, Rad6p-Rad18p monoubiquitinates Pol30p (PCNA) at lysine residue 164 to activate error-prone and error-free translesion repair via polymerases eta and zeta. Monoubiquitinated PCNA can be subsequently polyubiquitinated in a Rad5p-Mms2p-Ubc13p dependent manner to promote error-free postreplicational repair (12, reviewed in 7).

The E3 ubiquitin ligase Bre1p targets Rad6p to promoter regions and enables the enzyme to attach ubiquitin to lysine 123 in histone H2B (9, 13, 14). This chromatin modification is required for histone H3 methylation and downstream transcriptional silencing (15). In vitro, Rad6p is able to efficiently multiubiquitinate histones H2A, H2B, and H3 in the absence of an E3 enzyme, with the C-terminus of the protein facilitating Rad6p targeting to histones (16).

During amino-end rule degradation, Ubr1p and Rad6p are able to multiubiquinate various protein substrates, thus targeting them for degradation by ubiquitin-dependent protease (10, 17). The amino terminal domain of Rad6p has been shown to be required for Ubr1p interaction as well as E3-dependent protein degradation (18).

rad6 mutants display sensitivity to UV light, X rays, and many chemical mutagens; they have an elevated spontaneous-mutation rate but are incapable of DNA damage-induced mutagenesis. Cells lacking Rad6p also have silencing and sporulation defects but are hyperactive in mitotic recombination (reviewed in 19). Mutations in rhp6, the S. pombe ortholog of RAD6, also are defective in DNA repair, UV mutagenesis and sporulation (20). RAD6 homologs have also been identified in Drosophila and in humans; humans have two RAD6 homologs, the genes HHR6A (OMIM) and HHR6B (OMIM) (21, 22).

Last updated: 2006-04-12 Contact SGD

References cited on this page View Complete Literature Guide for RAD6
1) Jentsch S, et al.  (1987) The yeast DNA repair gene RAD6 encodes a ubiquitin-conjugating enzyme. Nature 329(6135):131-4
2) Rolla H, et al.  (2002) Mutant pso8-1 of Saccharomyces cerevisiae, sensitive to photoactivated psoralens, UV radiation, and chemical mutagens, contains a rad6 missense mutant allele. Curr Genet 41(4):217-23
3) Varshavsky A  (1996) The N-end rule: functions, mysteries, uses. Proc Natl Acad Sci U S A 93(22):12142-9
4) Game JC and Chernikova SB  (2009) The role of RAD6 in recombinational repair, checkpoints and meiosis via histone modification. DNA Repair (Amst) 8(4):470-82
5) Ulrich HD  (2009) Regulating post-translational modifications of the eukaryotic replication clamp PCNA. DNA Repair (Amst) 8(4):461-9
6) Stolz A, et al.  (2013) Previously unknown role for the ubiquitin ligase Ubr1 in endoplasmic reticulum-associated protein degradation. Proc Natl Acad Sci U S A 110(38):15271-6
7) Prakash S, et al.  (2005) Eukaryotic translesion synthesis DNA polymerases: specificity of structure and function. Annu Rev Biochem 74:317-53
8) Bailly V, et al.  (1997) Yeast DNA repair proteins Rad6 and Rad18 form a heterodimer that has ubiquitin conjugating, DNA binding, and ATP hydrolytic activities. J Biol Chem 272(37):23360-5
9) Wood A, et al.  (2003) Bre1, an E3 ubiquitin ligase required for recruitment and substrate selection of Rad6 at a promoter. Mol Cell 11(1):267-74
10) Dohmen RJ, et al.  (1991) The N-end rule is mediated by the UBC2(RAD6) ubiquitin-conjugating enzyme. Proc Natl Acad Sci U S A 88(16):7351-5
11) Prakash S, et al.  (1993) DNA repair genes and proteins of Saccharomyces cerevisiae. Annu Rev Genet 27:33-70
12) Hoege C, et al.  (2002) RAD6-dependent DNA repair is linked to modification of PCNA by ubiquitin and SUMO. Nature 419(6903):135-41
13) Hwang WW, et al.  (2003) A conserved RING finger protein required for histone H2B monoubiquitination and cell size control. Mol Cell 11(1):261-6
14) Robzyk K, et al.  (2000) Rad6-dependent ubiquitination of histone H2B in yeast. Science 287(5452):501-4
15) Dover J, et al.  (2002) Methylation of histone H3 by COMPASS requires ubiquitination of histone H2B by Rad6. J Biol Chem 277(32):28368-71
16) Sung P, et al.  (1988) The RAD6 protein of Saccharomyces cerevisiae polyubiquitinates histones, and its acidic domain mediates this activity. Genes Dev 2(11):1476-85
17) Sung P, et al.  (1991) Yeast RAD6 encoded ubiquitin conjugating enzyme mediates protein degradation dependent on the N-end-recognizing E3 enzyme. EMBO J 10(8):2187-93
18) Watkins JF, et al.  (1993) The extremely conserved amino terminus of RAD6 ubiquitin-conjugating enzyme is essential for amino-end rule-dependent protein degradation. Genes Dev 7(2):250-61
19) Ulrich HD  (2002) Degradation or maintenance: actions of the ubiquitin system on eukaryotic chromatin. Eukaryot Cell 1(1):1-10
20) Reynolds P, et al.  (1990) The rhp6+ gene of Schizosaccharomyces pombe: a structural and functional homolog of the RAD6 gene from the distantly related yeast Saccharomyces cerevisiae. EMBO J 9(5):1423-30
21) Koken M, et al.  (1991) Dhr6, a Drosophila homolog of the yeast DNA-repair gene RAD6. Proc Natl Acad Sci U S A 88(9):3832-6
22) Koken MH, et al.  (1992) Localization of two human homologs, HHR6A and HHR6B, of the yeast DNA repair gene RAD6 to chromosomes Xq24-q25 and 5q23-q31. Genomics 12(3):447-53