InnateDB: Systems Biology of the Innate Immune Response

Homo sapiens Protein: C1S

Summary

InnateDB Protein

IDBP-15861.6

Last Modified

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

Gene Symbol

C1S

Protein Name

complement component 1, s subcomponent

Synonyms

Species

Homo sapiens

Ensembl Protein

ENSP00000354057

InnateDB Gene

IDBG-15857 (C1S)

Protein Structure

UniProt Annotation

Function

C1s B chain is a serine protease that combines with C1q and C1r to form C1, the first component of the classical pathway of the complement system. C1r activates C1s so that it can, in turn, activate C2 and C4.

Subcellular Localization

Disease Associations

Complement component C1s deficiency (C1SD) [MIM:613783]: A rare defect resulting in C1 deficiency and impaired activation of the complement classical pathway. C1 deficiency generally leads to severe immune complex disease with features of systemic lupus erythematosus and glomerulonephritis. {ECO:0000269PubMed:11390518}. 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 19 experimentally validated interaction(s) in this database.

Experimentally validated
Total	19 [view]
Protein-Protein	15 [view]
Protein-DNA	3 [view]
Protein-RNA	0
DNA-DNA	1 [view]
RNA-RNA	0
DNA-RNA	0

Gene Ontology

Molecular Function

Accession	GO Term
GO:0003824	catalytic activity
GO:0004252	serine-type endopeptidase activity
GO:0005509	calcium ion binding
GO:0005515	protein binding
GO:0042802	identical protein binding

Biological Process

GO:0006508	proteolysis
GO:0006956	complement activation
GO:0006958	complement activation, classical pathway
GO:0045087	innate immune response (InnateDB)

Cellular Component

GO:0005576	extracellular region
GO:0070062	extracellular vesicular exosome
GO:0072562	blood microparticle

Protein Structure and Domains

PDB ID

InterPro

IPR000436 Sushi/SCR/CCP
IPR000859 CUB domain
IPR001254 Peptidase S1
IPR001314 Peptidase S1A, chymotrypsin-type
IPR001881 EGF-like calcium-binding domain
IPR009003 Trypsin-like cysteine/serine peptidase domain

PFAM

PF00084
PF00431
PF00089
PF07645

PRINTS

PR00722

PIRSF

SMART

SM00032
SM00042
SM00020
SM00179

TIGRFAMs

Post-translational Modifications

Modification

Cross-References

SwissProt