Transcriptional regulator; functions primarily as a transcriptional co-repressor with Tup1p but can also function as a transcriptional co-activator with Tup1p that recruits the SWI/SNF and SAGA complexes to promoters; target genes may be uniquely repressed by Cyc8p or Tup1p, subject to redundant repression, or in some cases de-repression of target genes in a cyc8 mutant is dependent upon TUP1 and vice versa; can form the prion [OCT+]
2345
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.
Summary
CYC8 is located on the right arm of chromosome II between SUS1 transcriptional regulator and RAD16 nucleotide excision repair protein; dubious ORF overlaps 5' end of CYC8 on opposite strand; coding sequence is 2901 nucleotides long with two variable CAA (Q) trinucleotide microsatellites and one variable CAAGCA (QA) microsatellite
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.
Summary
Cyc8p is 966 amino acids long, of average half-life, low in abundance; contains variable glutamine repeat near N-terminus, contains variable compound glutamine/alanine repeat near middle of protein; acetylated on 2 lysines, ubiquitinylated on K175, sumoylated on 5 lysines, phosphorylated on 37 residues
Length (a.a.)
966
Mol. Weight (Da)
107160.9
Isoelectric Point
4.65
Median Abundance (molecules/cell)
5404 +/- 1436
Half-life (hr)
10.5
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
Chromatin-remoding transcription factor that regulates transcription by RNA polymerase II; binds histone deacetylases and is involved in nucleosome positioning; present in transcriptional repressor complex with Tup1p
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
term name objects around within the visualization for easier viewing; click “Reset” to automatically redraw the
diagram; filter the genes that share GO Biological Process terms with the given gene by the number of terms they
share by clicking anywhere on the slider bar or dragging the tab to the desired filter number.
Macromolecular complex annotations are imported from the Complex Portal. These annotations have been derived from physical molecular interaction evidence extracted from the literature and cross-referenced in the entry, or by curator inference from information on homologs in closely related species or by inference from scientific background.
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.
Summary
Non-essential gene in S288C, essential gene in Sigma1278b; null grows slowly, buds in random pattern, has large rounded cells, short telomeres, decreased lifespan, and cannot respire; null is also sensitive to heat, oxidative stress, metals, acid, and antimalarial drug mefloquine; homozygous diploid null cannot sporulate
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.
Summary
Cyc8p interacts physically with proteins involved in transcription; CYC8 interacts genetically with genes involved in transcription
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
Cyc8p (also known as Ssn6p) acts with its partner Tup1p as a corepressor to regulate the expression of multiple genes under a variety of conditions. Tup1p-Cyc8p does not bind to DNA directly but is recruited to specific promoters by DNA binding proteins such as Alpha2p, Mig1p, and Crt1p. Evidence suggests that Tup1p-Cyc8p represses transcription by masking and inhibiting the transcriptional activation domains of the recruiting proteins. Tup1p interacts directly with histones H3 and H4, and mutation of these histones synergistically compromises Tup1p-Cyc8p-mediated repression. Histone hyperacetylation caused by combined mutations in genes encoding the histone deacetylases Rpd3p, Hos1p, and Hos2p abolishes repression by Tup1p-Cyc8p. Regulatory regions bound by Tup1p assume a distinct chromatin architecture including nucleosome-depleted regions, poorly positioned promoter nucleosomes and a larger number and wider distribution of accessible transcription factor binding sites. The Tup1p-Cyc8p corepressor complex is composed of one Cyc8p and four Tup1p subunits.
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.
Summary Paragraph
A summary of the locus, written by SGD Biocurators following a thorough review of the literature. Links
to gene names and curated GO terms are included within the Summary Paragraphs.
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).