Q12343 · MED4_YEAST

Function

function

Component of the Mediator complex, a coactivator involved in the regulated transcription of nearly all RNA polymerase II-dependent genes. Mediator functions as a bridge to convey information from gene-specific regulatory proteins to the basal RNA polymerase II transcription machinery. The Mediator complex, having a compact conformation in its free form, is recruited to promoters by direct interactions with regulatory proteins and serves for the assembly of a functional preinitiation complex with RNA polymerase II and the general transcription factors. The Mediator complex unfolds to an extended conformation and partially surrounds RNA polymerase II, specifically interacting with the unphosphorylated form of the C-terminal domain (CTD) of RNA polymerase II. The Mediator complex dissociates from the RNA polymerase II holoenzyme and stays at the promoter when transcriptional elongation begins.

Miscellaneous

Present with 1617 molecules/cell in log phase SD medium.

GO annotations

all annotationsall molecular functionvirus receptor activitydna bindingrna bindingcytoskeletal motor activitycatalytic activitygtpase activitystructural molecule activitytransporter activitycytoskeletal protein bindinglipid bindingcyclase activityantioxidant activityoxidoreductase activitytransferase activityhydrolase activitylyase activityisomerase activityligase activityprotein tag activitycargo receptor activityhistone bindingprotein folding chaperonetranslation regulator activitynutrient reservoir activityreceptor ligand activitymolecular transducer activitymolecular adaptor activitytoxin activitycell adhesion mediator activitymolecular function regulator activityvirus coreceptor activitycatalytic activity, acting on a proteincatalytic activity, acting on dnacatalytic activity, acting on rnamolecular carrier activitytranscription regulator activitygeneral transcription initiation factor activitymolecular sensor activitymolecular sequestering activityatp-dependent activityother molecular functionall biological processmitotic cell cyclecytokinesiscytoplasmic translationimmune system processmuscle system processcirculatory system processrenal system processrespiratory system processcarbohydrate metabolic processgeneration of precursor metabolites and energydna replicationdna repairdna recombinationchromatin organizationdna-templated transcriptionregulation of dna-templated transcriptiontrna metabolic processprotein foldingprotein glycosylationamino acid metabolic processmodified amino acid metabolic processlipid metabolic processvitamin metabolic processsulfur compound metabolic processintracellular protein transportnucleocytoplasmic transportautophagyinflammatory responsemitochondrion organizationcytoskeleton organizationmicrotubule-based movementperoxisome organizationlysosome organizationchromosome segregationcell adhesionestablishment or maintenance of cell polarityprogrammed cell deathphotosynthesismrna metabolic processsnrna metabolic processvesicle-mediated transportreproductive processdigestive system processsignalingcell differentiationprotein catabolic processextracellular matrix organizationregulatory ncrna-mediated gene silencingtelomere organizationcell junction organizationwound healingribosome biogenesiscilium organizationanatomical structure developmentcell motilitynervous system processendocrine processprotein maturationtransmembrane transportnucleobase-containing small molecule metabolic processhepaticobiliary system processmembrane organizationprotein-containing complex assemblycell wall organization or biogenesisnitrogen cycle metabolic processprotein localization to plasma membranedefense response to other organismdetoxificationmeiotic nuclear divisionmitotic nuclear divisionmitochondrial gene expressioncarbohydrate derivative metabolic processother biological processall cellular componentnuclear chromosomeextracellular regionextracellular spacecell wallnucleusnuclear envelopenucleoplasmchromosomenucleolusmitochondrionlysosomeendosomevacuoleperoxisomeendoplasmic reticulumgolgi apparatuslipid dropletmicrotubule organizing centercytosolribosomecytoskeletonplasma membraneciliumplastidthylakoidexternal encapsulating structureextracellular matrixcytoplasmic vesicleorganelleother cellular component
Cell color indicative of number of GO terms
AspectTerm
Cellular Componentcore mediator complex
Cellular Componentmediator complex
Cellular Componentnucleus
Molecular FunctionRNA polymerase II core promoter sequence-specific DNA binding
Molecular Functiontranscription coregulator activity
Biological Processcellular response to heat
Biological Processpositive regulation of transcription elongation by RNA polymerase II
Biological Processpositive regulation of transcription initiation by RNA polymerase II
Biological Processregulation of transcription by RNA polymerase II
Biological ProcessRNA polymerase II preinitiation complex assembly
Biological Processtranscription by RNA polymerase II

Keywords

Enzyme and pathway databases

Names & Taxonomy

Protein names

  • Recommended name
    Mediator of RNA polymerase II transcription subunit 4
  • Alternative names
    • Mediator complex subunit 4

Gene names

    • Name
      MED4
    • ORF names
      O3630
    • Ordered locus names
      YOR174W

Organism names

Accessions

  • Primary accession
    Q12343
  • Secondary accessions
    • D6W2N0

Proteomes

Organism-specific databases

Subcellular Location

Keywords

PTM/Processing

Features

Showing features for initiator methionine, modified residue, chain.

TypeIDPosition(s)Description
Initiator methionine1Removed
Modified residue2N-acetylserine
ChainPRO_00000963862-284Mediator of RNA polymerase II transcription subunit 4
Modified residue237Phosphothreonine; by KIN28
Modified residue242Phosphoserine

Keywords

Proteomic databases

PTM databases

Interaction

Subunit

Component of the Mediator complex, which is composed of at least 21 subunits that form three structurally distinct submodules. The Mediator head module contains MED6, MED8, MED11, SRB4/MED17, SRB5/MED18, ROX3/MED19, SRB2/MED20 and SRB6/MED22, the middle module contains MED1, MED4, NUT1/MED5, MED7, CSE2/MED9, NUT2/MED10, SRB7/MED21 and SOH1/MED31, and the tail module contains MED2, PGD1/MED3, RGR1/MED14, GAL11/MED15 and SIN4/MED16. The head and the middle modules interact directly with RNA polymerase II, whereas the elongated tail module interacts with gene-specific regulatory proteins. MED4 interacts directly with MED1, MED7 and SRB7/MED21.

Binary interactions

Protein-protein interaction databases

Miscellaneous

Family & Domains

Features

Showing features for region, compositional bias.

TypeIDPosition(s)Description
Region205-284Disordered
Compositional bias248-269Basic and acidic residues
Compositional bias270-284Acidic residues

Sequence similarities

Belongs to the Mediator complex subunit 4 family.

Phylogenomic databases

Family and domain databases

Sequence

  • Sequence status
    Complete
  • Length
    284
  • Mass (Da)
    32,205
  • Last updated
    1996-11-01 v1
  • Checksum
    D42A3C62D465DDAD
MSVQDTKAVEFSMGHIRSSSVSLVAEATSNTNSEDKLSKVQLYEDLCRYEDTLSKLVESVDRFKPNLDIAKDLIRTDEALFENVKLLAEYDNIYRNLQKIDKDSEELDSKTRKILEILNECHDELKALPMLEQVEFEKNTILQQRSKINSTELLDYATKLSKFTKIPPTFDKGAVGPNNFIWPAEDALRRGMLAMASLHSKELTRIPGEEVEETEVPTVPPSQSEEQKGQMAKKEGTPKTDSFIFDGTAKEVGDEADNTKDKEKEENNDDALDLDLDLFDPDDF

Features

Showing features for compositional bias.

TypeIDPosition(s)Description
Compositional bias248-269Basic and acidic residues
Compositional bias270-284Acidic residues

Keywords

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
U55021
EMBL· GenBank· DDBJ
AAB47419.1
EMBL· GenBank· DDBJ
Genomic DNA
Z75082
EMBL· GenBank· DDBJ
CAA99383.1
EMBL· GenBank· DDBJ
Genomic DNA
BK006948
EMBL· GenBank· DDBJ
DAA10946.1
EMBL· GenBank· DDBJ
Genomic DNA

Genome annotation databases

Similar Proteins

Disclaimer

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