SIR4 / YDR227W Overview


Standard Name
SIR4 1
Systematic Name
YDR227W
SGD ID
SGD:S000002635
Aliases
ASD1 , STE9 , UTH2
Feature Type
ORF , Verified
Description
SIR protein involved in assembly of silent chromatin domains; silent information regulator (SIR) along with SIR2 and SIR3; involved in assembly of silent chromatin domains at telomeres and the silent mating-type loci; some SIR4 alleles prolong lifespan; required for Ku-mediated telomerase recruitment, telomere lengthening, and telomere hypercluster formation in quiescent yeast cells 2 3 4 5 6
Name Description
Silent Information Regulator 1
Comparative Info
Sequence Details

Sequence

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.


Protein Details

Protein

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.)
1358
Mol. Weight (Da)
152084.6
Isoelectric Point
9.63
Median Abundance (molecules/cell)
1446 +/- 381
Half-life (hr)
4.4

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


View all SIR4 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.


Summary
Subunit of the chromatin silencing complex that binds to double-stranded DNA and nucleosomes; involved in chromatin silencing and tethering telomeres at the nuclear periphery; localizes to the telomeric region of nuclear chromosomes and to nuclear telomeric heterochromatin

View computational annotations

Molecular Function

Manually Curated

Cellular Component

Manually Curated

Complex

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

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; null mutant has reduced replicative lifespan, while the gain-of-function mutant has increased lifespan, but the lifespan of the homozygous diploid null is unchanged; reduction-of-function mutant displays decreased silencing at the silent mating type cassettes, HMR and HML, and overexpression decreases silencing at HMR, HML and telomeres; null mutant has decreased filamentous growth and is unable to undergo invasive growth; null mutant has an increased rate of chromosome loss, and both null and overexpressor have decreased telomere length; null mutant does not respond to alpha factor and conditional mutant is sterile, unable to shmoo or arrest the cell cycle in the presence of pheromone and produces very low levels of mating pheromone; conditional mutant has a bipolar budding pattern like diploids
Interaction Details

Interaction

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.


337 total interactions for 145 unique genes

Physical Interactions

  • Affinity Capture-MS: 38
  • Affinity Capture-RNA: 6
  • Affinity Capture-Western: 60
  • Biochemical Activity: 4
  • Co-crystal Structure: 6
  • Co-localization: 5
  • Co-purification: 4
  • Far Western: 1
  • PCA: 1
  • Proximity Label-MS: 1
  • Reconstituted Complex: 35
  • Two-hybrid: 69

Genetic Interactions

  • Dosage Rescue: 9
  • Negative Genetic: 4
  • Phenotypic Enhancement: 18
  • Phenotypic Suppression: 30
  • Synthetic Growth Defect: 18
  • Synthetic Rescue: 28
Regulation Details

Regulation

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.


Regulators
6
Targets
144
Expression Details

Expression

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: 1999-09-01

Literature Details

Literature

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.


Primary
172
Additional
224
Reviews
151

Resources