Complement component 3

C3
Available structures
PDB	Ortholog search: PDBe RCSB
List of PDB id codes
	4ONT, 1C3D, 1GHQ, 1W2S, 2A73, 2A74, 2GOX, 2I07, 2ICE, 2ICF, 2NOJ, 2QKI, 2WII, 2WIN, 2WY7, 2WY8, 2XQW, 2XWB, 2XWJ, 3D5R, 3D5S, 3G6J, 3L3O, 3L5N, 3NMS, 3OED, 3OHX, 3OXU, 3RJ3, 3T4A, 4HW5, 4HWJ, 4I6O, 4M76, 4ZH1, 5FOB, 5FO9, 5FO7, 5FO8, 5FOA
Identifiers
Aliases	C3, AHUS5, ARMD9, ASP, C3a, C3b, CPAMD1, HEL-S-62p, complement component 3, complement C3
External IDs	OMIM: 120700; MGI: 88227; HomoloGene: 68031; GeneCards: C3; OMA:C3 - orthologs
Gene location (Human)
Chr.	Chromosome 19 (human)
End	6,730,562 bp
Gene location (Mouse)
Chr.	Chromosome 17 (mouse)
End	57,535,136 bp
RNA expression pattern
	Top expressed in
	parietal pleura; ; palpebral conjunctiva; ; right lobe of liver; ; germinal epithelium; ; pericardium; ; peritoneum; ; gastric mucosa; ; left uterine tube; ; right adrenal cortex; ; left adrenal cortex;
	Top expressed in
	left lobe of liver; ; mesenteric lymph nodes; ; gallbladder; ; intercostal muscle; ; tunica adventitia of aorta; ; subcutaneous adipose tissue; ; superior surface of tongue; ; white adipose tissue; ; granulocyte; ; right lung;
	More reference expression data
	n/a
Gene ontology
Molecular function	C5L2 anaphylatoxin chemotactic receptor binding; protein binding; endopeptidase inhibitor activity; signaling receptor binding; serine-type endopeptidase activity;
Cellular component	blood microparticle; plasma membrane; extracellular fluid; extracellular region; extracellular exosome;
Biological process	G protein-coupled receptor signaling pathway; positive regulation of phagocytosis; positive regulation of protein phosphorylation; complement activation, alternative pathway; lipid metabolism; immune system process; complement activation; positive regulation of lipid storage; positive regulation of type IIa hypersensitivity; fatty acid metabolic process; positive regulation of angiogenesis; positive regulation of G protein-coupled receptor signaling pathway; positive regulation of apoptotic cell clearance; immune response; complement activation, classical pathway; regulation of immune response; positive regulation of activation of membrane attack complex; positive regulation of vascular endothelial growth factor production; inflammatory response; positive regulation of glucose transmembrane transport; regulation of complement activation; signal transduction; negative regulation of endopeptidase activity; regulation of triglyceride biosynthetic process; proteolysis; innate immune response;
	Sources:Amigo / QuickGO
Orthologs
	718
	12266
	ENSG00000125730
	ENSMUSG00000024164
	P01024
	P01027
	NM_000064
	NM_009778
	NP_000055
	NP_033908
	Wikidata
View/Edit Human	View/Edit Mouse

Complement component 3, often simply called C3, is a protein of the immune system that is found primarily in the blood. It plays a central role in the complement system of vertebrate animals and contributes to innate immunity. In humans it is encoded on chromosome 19 by a gene called C3.

Deficiencies and defects of C3 result in the affected person being immunocompromised and particularly vulnerable to bacterial infections.