GAL4 / YPL248C Overview

Standard Name
GAL4 1
Systematic Name
GAL81 23
Feature Type
ORF , Verified
DNA-binding transcription factor required for activating GAL genes; responds to galactose; repressed by Gal80p and activated by Gal3p 2
Name Description
GALactose metabolism
Comparative Info
Sequence Details


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.

GAL4 is located on the left arm of chromosome XVI near the telomere and between GYP5 Rab GTPase-activating protein and uncharacterized gene YPL247C; antisense GAL4 lncRNA overlaps GAL4 on the opposite strand; coding sequence is 2646 nucleotides long with an in-frame 15 nucleotide deletion (5 amino acids DRLAS) in some strains and 42 SNPs, 18 of which cause amino acid polymorphisms
Protein Details


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.

Gal4p is 881 amino acids long, very low in abundance; contains a Zn(2)Cys(6) fungal-type DNA-binding domain, a dimerization domain, and a fungal transcription factor domain; sumoylated on K2 and K708, phosphorylated on 9 residues; some strains have a 5-aa deletion (DRLAS) between the dimerization and transcription factor domains
Length (a.a.)
Mol. Weight (Da)
Isoelectric Point
Median Abundance (molecules/cell)
755 +/- 589


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. Click "YeastMine" to view all alleles in YeastMine.

gal4-C14Y | gal4-C38G | gal4-F869S | gal4-F869Y | gal4-I294M | gal4-I407V | gal4-K104UAA | ... Show all

View all GAL4 alleles in SGD search | YeastMine

Gene Ontology Details

Gene Ontology

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.

Sequence-specific DNA-binding RNA polymerase II transcription factor involved positive regulation of transcription in response to galactose; also binds and recruits other transcription factors

View computational annotations

Cellular Component

Manually Curated


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 Details


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.

Non-essential gene; null mutants cannot utilize galactose, and show increased resistance to antimalarial quinine, caffeine, and many common chemicals; conditional and reduced function mutants can be heat-sensitive; overexpression slows vegetative growth and increases filamentous growth
Interaction Details


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.

Gal4p interacts physically with proteins involved in transcription; GAL4 interacts genetically with genes involved in transcription

307 total interactions for 177 unique genes

Physical Interactions

  • Affinity Capture-MS: 23
  • Affinity Capture-RNA: 3
  • Affinity Capture-Western: 42
  • Biochemical Activity: 4
  • Co-crystal Structure: 3
  • Co-localization: 16
  • Co-purification: 1
  • Far Western: 1
  • FRET: 1
  • PCA: 36
  • Protein-peptide: 1
  • Reconstituted Complex: 50
  • Two-hybrid: 19

Genetic Interactions

  • Dosage Lethality: 3
  • Dosage Rescue: 2
  • Negative Genetic: 73
  • Phenotypic Enhancement: 2
  • Phenotypic Suppression: 4
  • Positive Genetic: 18
  • Synthetic Growth Defect: 1
  • Synthetic Rescue: 4
Regulation Details


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.

GAL4 encodes a transcription factor that is the archetypal member of the C6 zinc finger class, containing a DNA binding domain also known as the Zn2Cys6 binuclear zinc cluster or zinc knuckle. Gal4p is required for the upregulation of genes involved in galactose utilization, including GAL1, GAL2, GAL7, GAL10, and GAL80. When galactose is present as the sole carbon source, Gal4p binds to upstream activating sequences (UASGAL) in the promoter regions of target genes and recruits the transcription machinery to actively transcribe these genes. The number of UASGAL sites in the promoters of the target genes varies, which plays a role in the extent of activation possible. Gal4p binds the UASGAL site exclusively as a homodimer, and both DNA binding and dimerization are mediated by sequences in the N-terminal region. Transcriptional activation by Gal4p relies on an acidic C-terminal region that both stimulates transcription and also binds Gal80p, an inhibitor of Gal4p activity. This acidic activating domain is a site of monoubiquitylation. Gal4p also undergoes phosphorylation during activation, although studies indicate this phosphorylation is not essential for activity.
Expression Details


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.

Last Updated: 2010-12-01

Literature Details


All manually curated literature for the specified gene, organized into topics according to their relevance to the gene (Primary Literature, Additional Literature, or Review). Click "Literature Details" to view all literature information for this locus, including shared literature between genes.