SKI8/YGL213C Summary Help

Standard Name SKI8 1
Systematic Name YGL213C
Alias REC103 2
Feature Type ORF, Verified
Description Ski complex component and WD-repeat protein; mediates 3'-5' RNA degradation by the cytoplasmic exosome; also required for meiotic double-strand break recombination; null mutants have superkiller phenotype (1, 3, 4, 5, 6, 7 and see Summary Paragraph)
Name Description SuperKIller 1
Chromosomal Location
ChrVII:91247 to 90054 | ORF Map | GBrowse
Note: this feature is encoded on the Crick strand.
Genetic position: -149 cM
Gene Ontology Annotations All SKI8 GO evidence and references
  View Computational GO annotations for SKI8
Molecular Function
Manually curated
Biological Process
Manually curated
Cellular Component
Manually curated
Regulators 5 genes
Classical genetics
Large-scale survey
218 total interaction(s) for 137 unique genes/features.
Physical Interactions
  • Affinity Capture-MS: 32
  • Affinity Capture-Western: 6
  • Biochemical Activity: 1
  • PCA: 6
  • Reconstituted Complex: 3
  • Two-hybrid: 10

Genetic Interactions
  • Dosage Lethality: 1
  • Dosage Rescue: 3
  • Negative Genetic: 92
  • Phenotypic Enhancement: 1
  • Phenotypic Suppression: 3
  • Positive Genetic: 47
  • Synthetic Growth Defect: 4
  • Synthetic Lethality: 4
  • Synthetic Rescue: 5

Expression Summary
Length (a.a.) 397
Molecular Weight (Da) 44,231
Isoelectric Point (pI) 5.34
Phosphorylation PhosphoGRID | PhosphoPep Database
sequence information
ChrVII:91247 to 90054 | ORF Map | GBrowse
Note: this feature is encoded on the Crick strand.
Genetic position: -149 cM
Last Update Coordinates: 2011-02-03 | Sequence: 1996-07-31
Subfeature details
Most Recent Updates
Coordinates Sequence
CDS 1..1194 91247..90054 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 | Entrez Gene | Entrez RefSeq Protein | MIPS | Search all NCBI (Entrez) | UniProtKB
Primary SGDIDS000003181

The SKI complex is a cytoplasmic complex composed of a putative RNA helicase (Ski2p), a tetratricopeptide repeat protein (Ski3p) and a WD repeat protein (Ski8p) (3 and references therein). Along with the adaptor protein Ski7p, the SKI complex mediates the cytoplasmic functions of the exosome, a 3'-5' exonuclease complex (8, 9). Together, the SKI complex, Ski7p and the exosome function in a wide range of 3'-5' RNA catabolic processes that include the routine turnover of normal mRNAs (4), the degradation of aberrant mRNAs by 3'-5' nonsense-mediated decay (10) and non-stop mRNA decay (11), and the degradation of other cytoplasmic RNAs including unadenylated RNAs (12) and viral dsRNA (13, 1). Although the SKI complex was originally described as a heterotrimer containing Ski2p, Ski3p and Ski8p (3, 14), later work provides evidence that it is a heterotetramer containing one subunit each of Ski2p and Ski3p, and two subunits of Ski8p (15).

All members of the SKI complex are found in humans and the human genes for hSKI2 (SKIV2L) and hSKI8 (WDR61) have been identified (16, 17, 18). However, Ski7p is found only in a subset of Saccharomyces species (19); the closely related protein, Hbs1p, is likely to fill the role of Ski7p in other fungi and possibly other eukaryotes (20).

Null mutants of ski2, ski3, ski8 and ski7 have similar phenotypes. All have the superkiller phenotype indicative of increased accumulation or viral dsRNA (21 and references therein), and exhibit synthetic lethality with mutations in genes involved in 5'-3' mRNA decay (4, 8).

In addition to its function in RNA degradation, Ski8p plays an independent and genetically separable role in double-strand break formation during meiotic recombination. To fulfill this role, Ski8p relocates to the nucleus during meiotic prophase, where it interacts with Spo11p and mediates its localization it to chromosomal DNA (5, 22 and references therein).

Last updated: 2009-03-24 Contact SGD

References cited on this page View Complete Literature Guide for SKI8
1) Ridley SP, et al.  (1984) Superkiller mutations in Saccharomyces cerevisiae suppress exclusion of M2 double-stranded RNA by L-A-HN and confer cold sensitivity in the presence of M and L-A-HN. Mol Cell Biol 4(4):761-70
2) Gardiner JM, et al.  (1997) Molecular and genetic analysis of REC103, an early meiotic recombination gene in yeast. Genetics 146(4):1265-74
3) Brown JT, et al.  (2000) The yeast antiviral proteins Ski2p, Ski3p, and Ski8p exist as a complex in vivo. RNA 6(3):449-57
4) Jacobs JS, et al.  (1998) The 3' to 5' degradation of yeast mRNAs is a general mechanism for mRNA turnover that requires the SKI2 DEVH box protein and 3' to 5' exonucleases of the exosome complex. EMBO J 17(5):1497-506
5) Arora C, et al.  (2004) Antiviral protein Ski8 is a direct partner of Spo11 in meiotic DNA break formation, independent of its cytoplasmic role in RNA metabolism. Mol Cell 13(4):549-59
6) Cheng Z, et al.  (2004) Crystal structure of Ski8p, a WD-repeat protein with dual roles in mRNA metabolism and meiotic recombination. Protein Sci 13(10):2673-84
7) Madrona AY and Wilson DK  (2004) The structure of Ski8p, a protein regulating mRNA degradation: Implications for WD protein structure. Protein Sci 13(6):1557-65
8) van Hoof A, et al.  (2000) Function of the ski4p (Csl4p) and Ski7p proteins in 3'-to-5' degradation of mRNA. Mol Cell Biol 20(21):8230-43
9) Araki Y, et al.  (2001) Ski7p G protein interacts with the exosome and the Ski complex for 3'-to-5' mRNA decay in yeast. EMBO J 20(17):4684-93
10) Mitchell P and Tollervey D  (2003) An NMD pathway in yeast involving accelerated deadenylation and exosome-mediated 3'-->5' degradation. Mol Cell 11(5):1405-13
11) van Hoof A, et al.  (2002) Exosome-mediated recognition and degradation of mRNAs lacking a termination codon. Science 295(5563):2262-4
12) Brown JT and Johnson AW  (2001) A cis-acting element known to block 3' mRNA degradation enhances expression of polyA-minus mRNA in wild-type yeast cells and phenocopies a ski mutant. RNA 7(11):1566-77
13) Toh-E A, et al.  (1978) Chromosomal superkiller mutants of Saccharomyces cerevisiae. J Bacteriol 136(3):1002-7
14) Wang L, et al.  (2005) Domain interactions within the Ski2/3/8 complex and between the Ski complex and Ski7p. RNA 11(8):1291-302
15) Synowsky SA and Heck AJ  (2008) The yeast Ski complex is a hetero-tetramer. Protein Sci 17(1):119-25
16) Lee SG, et al.  (1995) Identification and characterization of a human cDNA homologous to yeast SKI2. Genomics 25(3):660-6
17) Dangel AW, et al.  (1995) Human helicase gene SKI2W in the HLA class III region exhibits striking structural similarities to the yeast antiviral gene SKI2 and to the human gene KIAA0052: emergence of a new gene family. Nucleic Acids Res 23(12):2120-6
18) Zhu B, et al.  (2005) The human PAF complex coordinates transcription with events downstream of RNA synthesis. Genes Dev 19(14):1668-73
19) Atkinson GC, et al.  (2008) Evolution of nonstop, no-go and nonsense-mediated mRNA decay and their termination factor-derived components. BMC Evol Biol 8:290
20) van Hoof A  (2005) Conserved functions of yeast genes support the duplication, degeneration and complementation model for gene duplication. Genetics 171(4):1455-61
21) Wickner RB  (1996) Double-stranded RNA viruses of Saccharomyces cerevisiae. Microbiol Rev 60(1):250-65
22) Keeney S and Neale MJ  (2006) Initiation of meiotic recombination by formation of DNA double-strand breaks: mechanism and regulation. Biochem Soc Trans 34(Pt 4):523-5