| Standard Name | GAL80 1 |
|---|---|
| Systematic Name | YML051W |
| Feature Type | ORF, Verified |
| Description | Transcriptional regulator involved in the repression of GAL genes in the absence of galactose; inhibits transcriptional activation by Gal4p; inhibition relieved by Gal3p or Gal1p binding (2 and see Summary Paragraph) |
| Name Description | GALactose metabolism |
| Chromosomal Location | |
|---|---|
| Genetic position: -33 cM |
| View Computational GO annotations for GAL80 | |
| Molecular Function | |
| Manually curated | |
| Biological Process | |
| Manually curated | |
| Cellular Component | |
| Manually curated |
| Binding motifs | Predicted GAL80 Binding Site Locations |
|---|---|
| | |
| Regulatory modules | predicted: stressResponse (511, 433, 367) |
| Resources |
| Classical genetics | |
|---|---|
| conditional | |
| dominant negative | |
| null | |
| Large-scale survey | |
| null |
|
| overexpression | |
| Resources |
| 179 total interaction(s) for 114 unique genes/features. | |
| Physical Interactions |
|
| Genetic Interactions |
|
| Resources |
|
|
| |
| Resources |
| Localization | |
|---|---|
| Phosphorylation | PhosphoGRID | PhosphoPep Database |
| Structure | |
| Homologs |
|
| |||||||||||||
| Genetic position: -33 cM | |||||||||||||
| Last Update | Coordinates: 1996-07-31 | Sequence: 1996-07-31 | ||||||||||||
| Subfeature details |
| ||||||||||||
| Retrieve sequences | |||||||||||||
| 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 SGDID | S000004515 |
|---|
GAL80 encodes a transcriptional repressor involved in transcriptional regulation in response to galactose (2). In conjunction with Gal4p and Gal3p, Gal80p coordinately regulates the expression of genes containing a GAL upstream activation site in their promoter (UAS-GAL), which includes the GAL metabolic genes GAL1, GAL10, GAL2, and GAL7 (reviewed in 3). Cells null for gal80 constitutively express GAL genes, even in non-inducing media (4).
In the absence of galactose, Gal80p binds, as a dimer, to the transcription factor Gal4p, thus preventing Gal4p from recruiting other factors of the Pol II transcription machinery (5). In the presence of galactose,Gal3p sequesters Gal80p in the cytoplasm which relieves inhibition of Gal4p and results in GAL gene expression (6). Gal80p interacts with Gal3p as a monomer and only in the presence of both galactose and ATP (2). In the absence of Gal3p, the Gal1p galactokinase can interact with and partially inhibit Gal80p function (2, 7).
GAL80 transcription is also regulated by the Gal3p/Gal80p/Gal4p feedback mechanism that regulates the other GAL genes. However, unlike expression of the GAL structural genes, which is tightly controlled because of the presence of multiple UAS-GALs in their promoters, GAL80 has high basal levels of transcription due to the presence of only a single UAS-GAL in its promoter (8).
| 1) | Hopper JE and Rowe LB (1978) Molecular expression and regulation of the galactose pathway genes in Saccharomyces cerevisiae. Distinct messenger RNAs specified by the Gali and Gal7 genes in the Gal7-Gal10-Gal1 cluster. J Biol Chem 253(20):7566-9 |
| 2) | Timson DJ, et al. (2002) Gal3p and Gal1p interact with the transcriptional repressor Gal80p to form a complex of 1:1 stoichiometry. Biochem J 363(Pt 3):515-20 |
| 3) | Lohr D, et al. (1995) Transcriptional regulation in the yeast GAL gene family: a complex genetic network. FASEB J 9(9):777-87 |
| 4) | Torchia TE, et al. (1984) Disruption of regulatory gene GAL80 in Saccharomyces cerevisiae: effects on carbon-controlled regulation of the galactose/melibiose pathway genes. Mol Cell Biol 4(8):1521-7 |
| 5) | Pilauri V, et al. (2005) Gal80 dimerization and the yeast GAL gene switch. Genetics 169(4):1903-14 |
| 6) | Peng G and Hopper JE (2002) Gene activation by interaction of an inhibitor with a cytoplasmic signaling protein. Proc Natl Acad Sci U S A 99(13):8548-53 |
| 7) | Bhat PJ and Hopper JE (1992) Overproduction of the GAL1 or GAL3 protein causes galactose-independent activation of the GAL4 protein: evidence for a new model of induction for the yeast GAL/MEL regulon. Mol Cell Biol 12(6):2701-7 |
| 8) | Melcher K and Xu HE (2001) Gal80-Gal80 interaction on adjacent Gal4p binding sites is required for complete GAL gene repression. EMBO J 20(4):841-51 |





