Basic leucine zipper transcription factor of the ATF/CREB family; forms a complex with Tup1p and Cyc8p to both activate and repress transcription; cytosolic and nuclear protein involved in osmotic and oxidative stress responses
123456
The S. cerevisiae Reference Genome sequence is derived from laboratory strain
S288C. Download DNA or protein sequence, view genomic context and
coordinates. Click "Sequence Details" to view all sequence information for this locus, including that
for other strains.
Basic sequence-derived (length, molecular weight, isoelectric point) and experimentally-determined (median abundance, median absolute deviation) protein information. Click "Protein Details" for further information about the protein such as half-life, abundance, domains, domains shared with other proteins, protein sequence retrieval for various strains, physico-chemical properties, protein modification sites, and external identifiers for the protein.
Length (a.a.)
647
Mol. Weight (Da)
70205.2
Isoelectric Point
9.84
Median Abundance (molecules/cell)
1310 +/- 774
Half-life (hr)
4.6
Alleles
Curated mutant alleles for the specified gene, listed alphabetically. Click on the allele name to open the allele page. Click "SGD search" to view all alleles in search results.
GO Annotations consist of four mandatory components: a gene product, a term from one of the three
Gene Ontology (GO) controlled vocabularies
(Molecular Function,
Biological Process, and
Cellular Component), a reference, and an
evidence code. SGD has manually curated and high-throughput GO Annotations, both derived from the
literature, as well as computational, or predicted, annotations. Click "Gene Ontology Details" to view
all GO information and evidence for this locus as well as biological processes it shares with other genes.
Summary
Cytosolic and nuclear transcription factor involved in response to osmotic stress
Functional Networks display how gene products work together in biological systems. The Shared Annotations
network shows genes with similar GO annotations, suggesting functional relationships. GO-CAMs (Gene
Ontology Causal Activity Models) are manually curated pathway models that illustrate how molecular
activities of multiple gene products connect through causal relationships to carry out biological
processes. GO-CAMs integrate Molecular Function, Biological Process, and Cellular Component information
into unified pathway representations based on published experimental evidence. Click "View GO-CAM at Gene
Ontology" to explore the interactive model at AmiGO.
Click on a gene or Biological Process GO term name to go to its specific page within SGD; drag any of the gene or GO
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Phenotype annotations for a gene are curated single mutant phenotypes that require an observable
(e.g., "cell shape"), a qualifier (e.g., "abnormal"), a mutant type (e.g., null), strain background,
and a reference. In addition, annotations are classified as classical genetics or high-throughput
(e.g., large scale survey, systematic mutation set). Whenever possible, allele information and
additional details are provided. Click "Phenotype Details" to view all phenotype annotations and
evidence for this locus as well as phenotypes it shares with other genes.
Interaction annotations are curated by BioGRID and include physical
or genetic interactions observed
between at least two genes. An interaction annotation is composed of the interaction type, name of the
interactor, assay type (e.g., Two-Hybrid), annotation type (e.g., manual or high-throughput), and a
reference, as well as other experimental details. Click "Interaction Details" to view all interaction
annotations and evidence for this locus, including an interaction visualization.
The number of putative Regulators (genes that regulate it) and Targets (genes it regulates) for the
given locus, based on experimental evidence. This evidence includes data generated through
high-throughput techniques. Click "Regulation Details" to view all regulation annotations, shared GO
enrichment among regulation Targets, and a regulator/target diagram for the locus.
Summary
SKO1 encodes a transcriptional repressor of the ATF/CREB family, containing a bZIP structural motif which consists of a leucine zipper that mediates dimerization and an adjacent basic region that contacts DNA. Sko1p binds as a homodimer the ATF/CREB consensus sequence TGACGTCA, and represses transcription both by recruiting the Cyc8-Tup1 corepressor and by directly competing with Aca1p and Cst6p for target sites. Sko1p regulates a transcriptional network upon osmotic stress, binding promoters of other transcription factors including MSN2, MOT3, ROX1, MGA1, and GAT2, and also the promoter of the phosphatase encoded by PTP3, a key component of the signal transduction pathway. Sko1p is also important for recruitment of SAGA histone acetylase and SWI/SNF nucleosome-remodeling complexes to osmotic-inducible promoters. Overall, S. cerevisiae contains approximately 40 Sko1p target promoters. ENA1 is a target of Sko1p, and it is responsible for salt regulation via the HOG pathway. Target genes also include SUC2, GRE2, AHP1, SFA1, GLR1, YML131W, and COS8. During hyperosmotic stress, Hog1p MAP kinase associates with target promoters and phosphorylates the amino terminus of Sko1p, disrupting its interaction with the Cyc8-Tup1 corepressor and thus converting Sko1p into a transcriptional activator. Sko1p is localized to the nucleus in unstressed cells, and becomes redistributed to the cytosol upon severe salt stress. Sko1p nuclear localization depends on the stress-inhibited protein kinase A (PKA), which phosphorylates Sko1p near its bZIP domain.
Expression data are derived from records contained in the
Gene Expression Omnibus (GEO), and are first log2
transformed and normalized. Referenced datasets may contain one or more condition(s), and as a result
there may be a greater number of conditions than datasets represented in a single clickable histogram
bar. The histogram division at 0.0 separates the down-regulated (green) conditions and datasets from
those that are up-regulated (red). Click "Expression Details" to view all expression annotations and
details for this locus, including a visualization of genes that share a similar expression pattern.
All manually curated literature for the specified gene, shown as a count of references by year of
publication followed by the most recent papers. Click "Literature Details" or "See all"
to view all literature information for this locus, organized into topics according to their
relevance to the gene (Primary Literature, Additional Literature, or Review).