SIN4 / YNL236W Overview

Standard Name
SIN4 1 2
Systematic Name
MED16 7 , BEL2 8 , GAL22 , SDI3 9 , SSF5 , SSN4 , TSF3 5 , RYE1 , SSX3 10
Feature Type
ORF , Verified
Subunit of the RNA polymerase II mediator complex; associates with core polymerase subunits to form the RNA polymerase II holoenzyme; contributes to both positive and negative transcriptional regulation; dispensible for basal transcription 3 4 5 6
Name Description
Switch INdependent
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.

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)
2633 +/- 913
Half-life (hr)


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 SIN4 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.

Subunit of the core mediator complex that acts as a bridge between transcription factors and RNA polymerase II; involved in both positive and negative regulation of transcription

View computational annotations

Molecular Function

Manually Curated

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.

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.

954 total interactions for 605 unique genes

Physical Interactions

  • Affinity Capture-MS: 103
  • Affinity Capture-RNA: 3
  • Affinity Capture-Western: 22
  • Co-purification: 9
  • Two-hybrid: 13

Genetic Interactions

  • Dosage Lethality: 1
  • Dosage Rescue: 5
  • Negative Genetic: 540
  • Phenotypic Enhancement: 12
  • Phenotypic Suppression: 16
  • Positive Genetic: 156
  • Synthetic Growth Defect: 32
  • Synthetic Lethality: 19
  • Synthetic Rescue: 23
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.

SIN4 (also called MED16) encodes a component of the tail module of the Mediator transcriptional regulation complex. The Mediator complex is highly conserved from yeast to human, and is a central player in the transcriptional regulation of protein-coding genes, being required for nearly all transcription by RNA polymerase II (RNAPII). Mediator bridges activators and the general transcription machinery. The core Mediator complex contains three distinct head, middle, and tail modules. Sin4p, Nut1p, Pgd1p, Med2p, and Gal11p are part of the tail module, which has a gene-selective, as opposed to a general, role in transcription, and is largely dedicated to the activation of genes involved in cellular responses to environmental signals. Pgd1p, Med2p, and Gal11p interact with gene-specific transcriptional activators such as Gcn4p. By interacting with activators, Mediator tail module subunits signal through the head and middle modules, which interact with general transcription factors and RNAPII subunits, to the basal transcription machinery to regulate transcription initiation. The tail module preferentially targets stress-regulated, TATA-containing, SAGA- and Swi/Snf-dependent genes, and may function along with specific chromatin regulators to provide a platform for preinitiation complex (PIC) formation at these highly regulated loci. Subunits of the Mediator tail module are also required for the activation of metabolic 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.

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.