InnateDB: Systems Biology of the Innate Immune Response

Homo sapiens Protein: C1QB

Summary

InnateDB Protein

IDBP-93749.5

Last Modified

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

Gene Symbol

C1QB

Protein Name

complement component 1, q subcomponent, B chain

Synonyms

Species

Homo sapiens

Ensembl Protein

ENSP00000313967

InnateDB Gene

IDBG-93747 (C1QB)

Protein Structure

UniProt Annotation

Function

C1q associates with the proenzymes C1r and C1s to yield C1, the first component of the serum complement system. The collagen-like regions of C1q interact with the Ca(2+)-dependent C1r(2)C1s(2) proenzyme complex, and efficient activation of C1 takes place on interaction of the globular heads of C1q with the Fc regions of IgG or IgM antibody present in immune complexes.

Subcellular Localization

Secreted.

Disease Associations

Complement component C1q deficiency (C1QD) [MIM:613652]: A disorder caused by impaired activation of the complement classical pathway. It generally leads to severe immune complex disease with features of systemic lupus erythematosus and glomerulonephritis. {ECO:0000269PubMed:9476130}. 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 13 experimentally validated interaction(s) in this database.

Experimentally validated
Total	13 [view]
Protein-Protein	12 [view]
Protein-DNA	1 [view]
Protein-RNA	0
DNA-DNA	0
RNA-RNA	0
DNA-RNA	0

Gene Ontology

Molecular Function

Accession	GO Term
GO:0005515	protein binding
GO:0042803	protein homodimerization activity

Biological Process

GO:0006956	complement activation
GO:0006958	complement activation, classical pathway
GO:0045087	innate immune response (InnateDB)
GO:0048839	inner ear development

Cellular Component

GO:0005576	extracellular region
GO:0005581	collagen trimer
GO:0005602	complement component C1 complex
GO:0070062	extracellular vesicular exosome
GO:0072562	blood microparticle