InnateDB: Systems Biology of the Innate Immune Response

Homo sapiens Protein: POLR3B

Summary

InnateDB Protein

IDBP-54800.6

Last Modified

2014-10-13 [Report errors or provide feedback]

Gene Symbol

POLR3B

Protein Name

polymerase (RNA) III (DNA directed) polypeptide B

Synonyms

Species

Homo sapiens

Ensembl Protein

ENSP00000228347

InnateDB Gene

IDBG-54798 (POLR3B)

Protein Structure

UniProt Annotation

Function

DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Second largest core component of RNA polymerase III which synthesizes small RNAs, such as 5S rRNA and tRNAs. Proposed to contribute to the polymerase catalytic activity and forms the polymerase active center together with the largest subunit. Pol III is composed of mobile elements and RPC2 is part of the core element with the central large cleft and probably a clamp element that moves to open and close the cleft (By similarity). Plays a key role in sensing and limiting infection by intracellular bacteria and DNA viruses. Acts as nuclear and cytosolic DNA sensor involved in innate immune response. Can sense non-self dsDNA that serves as template for transcription into dsRNA. The non-self RNA polymerase III transcripts, such as Epstein-Barr virus-encoded RNAs (EBERs) induce type I interferon and NF- Kappa-B through the RIG-I pathway. {ECO:0000250, ECO:0000269PubMed:19609254, ECO:0000269PubMed:19631370}.

Subcellular Localization

Nucleus {ECO:0000250}.

Disease Associations

Leukodystrophy, hypomyelinating, 8, with or without oligodontia and/or hypogonadotropic hypogonadism (HLD8) [MIM:614381]: An autosomal recessive neurodegenerative disorder characterized by early childhood onset of cerebellar ataxia and mild intellectual disabilities associated with diffuse hypomyelination apparent on brain MRI. Variable features include oligodontia and/or hypogonadotropic hypogonadism. {ECO:0000269PubMed:22036171, ECO:0000269PubMed:22036172}. Note=The disease is caused by mutations affecting the gene represented in this entry.

Tissue Specificity

Comments

Interactions

Number of Interactions

This gene and/or its encoded proteins are associated with 18 experimentally validated interaction(s) in this database.

Experimentally validated
Total	18 [view]
Protein-Protein	18 [view]
Protein-DNA	0
Protein-RNA	0
DNA-DNA	0
RNA-RNA	0
DNA-RNA	0

Gene Ontology

Molecular Function

Accession	GO Term
GO:0003677	DNA binding
GO:0003899	DNA-directed RNA polymerase activity
GO:0032549	ribonucleoside binding
GO:0046872	metal ion binding

Biological Process

GO:0006351	transcription, DNA-templated
GO:0006383	transcription from RNA polymerase III promoter
GO:0006385	transcription elongation from RNA polymerase III promoter
GO:0006386	termination of RNA polymerase III transcription
GO:0010467	gene expression
GO:0032481	positive regulation of type I interferon production
GO:0032728	positive regulation of interferon-beta production
GO:0045087	innate immune response
GO:0045089	positive regulation of innate immune response
GO:0051607	defense response to virus

Cellular Component

GO:0005654	nucleoplasm
GO:0005666	DNA-directed RNA polymerase III complex
GO:0005829	cytosol

Protein Structure and Domains

PDB ID

InterPro

IPR007120 DNA-directed RNA polymerase, subunit 2, domain 6
IPR007641 RNA polymerase Rpb2, domain 7
IPR007642 RNA polymerase Rpb2, domain 2
IPR007644 RNA polymerase, beta subunit, protrusion
IPR007645 RNA polymerase Rpb2, domain 3
IPR007646 RNA polymerase Rpb2, domain 4
IPR007647 RNA polymerase Rpb2, domain 5

PFAM