Preferred Label : Complement Component-4;
NCIt synonyms : C4;
NCIt related terms : Complement C4;
NCIt definition : Complement component-4 (1744 aa, 193 kDa) is part of the complement cascade, which
mediates the innate immune response to infection. The full length protein is a precursor
that is secreted as a trimeric molecule containing an alpha, beta and gamma chain.
When the complement cascade is initiated, the protein is cleaved. This proteolysis
releases both the alpha chain, C4 anaphylatoxin, which stimulates inflammation, and
a dimer of the beta and gamma chains, which mediates the interaction between the antigen-antibody
complex and other complement components.;
Alternative definition : NICHD: An early component of the classical and mannose binding lectin (MBL) complement
activation pathways. C4 is consumed by proteolysis upon activation of the classical
and MBL pathways, but not the alternative pathway. C4 levels are generally low in
active immune complex diseases mediated by classical or MBL activation, but not alternative
activation, with the canonical example being systemic lupus erythematosus.;
NCIt note : Human complement component C4 is polymorphic at two loci, C4A and C4B. 13 alleles
of C4A and 22 alleles of C4B have been detected. The C4A alleles carry the Rodgers
(Rg) blood group antigens while the C4B alleles carry the Childo (Ch) blood group
antigens. (SwissProt);
Origin ID : C70618;
UMLS CUI : C0009516;
Biochemical function of gene products
- Semantic type(s)
- UMLS correspondences (same concept)
- concept_is_in_subset
- gene_encodes_gene_product
- gene_product_has_biochemical_function
- gene_product_has_organism_source
- gene_product_plays_role_in_biological_process
- has_gene_product_element
- related_to_genetic_biomarker
