SWI5 / YDR146C Overview

Standard Name
SWI5 1 2
Systematic Name
Feature Type
ORF , Verified
Transcription factor that recruits Mediator and Swi/Snf complexes; activates transcription of genes expressed at the M/G1 phase boundary and in G1 phase; required for expression of the HO gene controlling mating type switching; localization to nucleus occurs during G1 and appears to be regulated by phosphorylation by Cdc28p kinase; SWI5 has a paralog, ACE2, that arose from the whole genome duplication 2 3 4 5 6 7 8 9
Name Description
SWItching deficient 2
ACE2 9
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.

SWI5 has a paralog, ACE2, that arose from the whole genome duplication
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.

Length (a.a.)
Mol. Weight (Da)
Isoelectric Point
Median Abundance (molecules/cell)
1179 +/- 782
Half-life (min)


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.

View all SWI5 alleles in SGD search

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 in regulation of the mitotic cell cycle and of mating-type switching; localizes to both the nucleus and the cytoplasm

View computational annotations

Cellular Component

Manually Curated
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; mutations prevent mating type switching; diploids show rough colony morphology; in systematic studies null mutation causes cell cycle delay at G1 phase, reduced competitive fitness and increased replicative lifespan
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.

The swi5 null mutant is viable; the null mutant of paralog ace2 is viable; the swi5 ace2 double mutant displays a phenotypic enhancement.

639 total interactions for 430 unique genes

Physical Interactions

  • Affinity Capture-MS: 16
  • Affinity Capture-RNA: 5
  • Affinity Capture-Western: 7
  • Biochemical Activity: 5
  • Co-localization: 8
  • PCA: 1
  • Reconstituted Complex: 10
  • Two-hybrid: 16

Genetic Interactions

  • Dosage Growth Defect: 2
  • Dosage Lethality: 5
  • Dosage Rescue: 5
  • Negative Genetic: 404
  • Phenotypic Enhancement: 7
  • Phenotypic Suppression: 10
  • Positive Genetic: 96
  • Synthetic Growth Defect: 20
  • Synthetic Lethality: 6
  • Synthetic Rescue: 16
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.

SWI5 encodes a transcription factor that is a member of the C2H2 zinc finger class. During the M-to-G1 transition in mitosis, Swi5p finalizes mitotic exit by activating transcription of SIC1, which encodes an inhibitor of cyclin-dependent kinase. Other targets of Swi5p activation include EGT2, involved in cell separation; ASH1, encoding a transcriptional repressor that inhibits mating type switching in daughter cells; and HO (YDL227C), encoding the endonuclease required for mating type switching. Swi5p activates HO transcription in concert with the homeodomain transcriptional activator Pho2p, and also recruits the Swi/Snf, SAGA, and Mediator complexes to the HO promoter. Swi5p activity is regulated by its nuclear localization, which in turn is controlled by phosphorylation. During anaphase and early telophase, phosphorylation of the nuclear localization sites of Swi5p, mediated by mitotic cyclin-dependent kinase, prevents Swi5p from entering the nucleus. In late telophase, these sites are dephosphorylated by Cdc14p, allowing Swi5 to enter both mother and daughter nuclei. Since Swi5p lacks a nuclear export sequence, it remains in the nuclei until early G1 phase, when it is degraded. Swi5p has a paralog, Ace2p, which also acts at the end of mitosis but regulates a distinct set of genes.
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: 1999-12-03

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.