S. cerevisiae Gene SIR1 (YKR101W)
  Description: Protein involved in repression of transcription at the silent mating-type loci HML and HMR recruitment to silent chromatin requires interactions with Orc1p and with Sir4p, through a common Sir1p domain binds to centromeric chromatin
Transcript (Including UTRs)
   Position: sacCer3 chrXI:640,540-642,504 Size: 1,965 Total Exon Count: 1 Strand: +
Coding Region
   Position: sacCer3 chrXI:640,540-642,504 Size: 1,965 Coding Exon Count: 1 

Page IndexSequence and LinksUniProtKB CommentsProtein StructureOther SpeciesGO Annotations
Other NamesMethods
Data last updated at UCSC: 2011-08-29

-  Sequence and Links to Tools and Databases
Genomic Sequence (chrXI:640,540-642,504)mRNAProtein (654 aa)
Gene SorterGenome BrowserOther Species FASTASGDUniProtKB

-  Comments and Description Text from UniProtKB
DESCRIPTION: RecName: Full=Regulatory protein SIR1; AltName: Full=Heterochromatin protein SIR1; AltName: Full=Silent information regulator 1;
FUNCTION: Involved in the establishment, but not the maintenance, of heterochromatic silencing at the cryptic mating-type loci HMR and HML. Is recruited by interacting with the ORC1 subunit of the origin recognition complex (ORC), which binds to HML-I or HMR-E silencers, DNA elements that direct the formation of silent chromatin at the mating-type loci. Establishes transcriptional silencing by recruiting the three other SIR proteins, SIR2, SIR3, and SIR4, that function directly in silenced chromatin and establish repression. Also found in centromeric chromatin. Binds to and helps retain CAC1, a subunit of chromatin assembly factor I (CAF-I) at centromeric loci independent on the other SIR proteins.
SUBUNIT: Interacts (via OIR domain) with ORC1 (via BAH domain). Interacts with SIR4. Interacts with CAC1.
SUBCELLULAR LOCATION: Nucleus. Chromosome, centromere. Note=Associated primarily with the HMR-E silencer at the HMR locus.
SEQUENCE CAUTION: Sequence=AAA35046.1; Type=Erroneous initiation; Sequence=CAA82181.1; Type=Erroneous initiation;

-  Protein Domain and Structure Information
  InterPro Domains: Graphical view of domain structure
IPR021646 - Regulatory_Sir1

Pfam Domains:
PF11603 - Regulatory protein Sir1

Protein Data Bank (PDB) 3-D Structure
MuPIT help

- X-ray

- X-ray

- X-ray

ModBase Predicted Comparative 3D Structure on P21691
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-  Orthologous Genes in Other Species
  Orthologies between human, mouse, and rat are computed by taking the best BLASTP hit, and filtering out non-syntenic hits. For more distant species reciprocal-best BLASTP hits are used. Note that the absence of an ortholog in the table below may reflect incomplete annotations in the other species rather than a true absence of the orthologous gene.
HumanMouseRatZebrafishD. melanogasterC. elegans
No orthologNo orthologNo orthologNo orthologNo orthologGenome Browser
     Gene Details
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     Protein Sequence

-  Gene Ontology (GO) Annotations with Structured Vocabulary
  Molecular Function:
GO:0003682 chromatin binding
GO:0005515 protein binding
GO:0043565 sequence-specific DNA binding

Biological Process:
GO:0006343 establishment of chromatin silencing
GO:0006351 transcription, DNA-templated
GO:0006355 regulation of transcription, DNA-templated
GO:0030466 chromatin silencing at silent mating-type cassette

Cellular Component:
GO:0000775 chromosome, centromeric region
GO:0005634 nucleus
GO:0005677 chromatin silencing complex
GO:0005694 chromosome

-  Other Names for This Gene
Protein: P21691 (aka SIR1_YEAST)

-  SGD Genes Methods, Credits, and Data Use Restrictions
  Click here for details on how this gene model was made and data restrictions if any.