Complement system (WP2806)
Homo sapiens
The complement activation takes place through one or more of the well-established (alternative, classical or lectin) pathways consisting of plasma and membrane-bound proteins. All three pathways converge at the level of complement C3 [https://doi.org/10.6072/H0.MP.A004235.01] and are controlled by regulators [https://doi.org/10.1038/ni.1923]. Complement C3 belongs to the alpha-2-macroglobulin family of proteins, and consists of a alpha-chain and an beta-chain. Cleavage of C3 which can be initiated by one or more of the above three distinct pathways, into C3b[Proteolysis@23-667,749-1663] and C3a [Proteolysis@672-748] is an important step in the complement activation cascade. Classical and lectin pathways, when activated with recognition of pathogens (or immune complexes) use C3-convertase [C4b2a] to cleave complement C3 into C3a and C3b [https://doi.org/10.1084/jem.125.2.359]. However, in alternative pathway a small fraction of the C3 molecules are hydrolyzed to C3(H20) exposing new binding sites. This hydrated C3 [C3(H20)] recruits complement factor B [fB], which is then cleaved by complement factor D [fD] to result in formation of the minor form of C3-convertase [C3(H20)Bb] that cleaves C3 into C3a and C3b [https://doi.org/10.1084/jem.154.3.856]. Further, addition of C3b to C3 convertase [C3bBb or C4b2a] results in C5 convertase [C3bBb3b or C4b2a3b], that cleaves complement C5 to C5a and C5b, is the last enzymatic step of the complement activation cascade [https://doi.org/10.1074/jbc.273.27.16828][https://www.ncbi.nlm.nih.gov/pubmed/?term=2387864]. During complement activation C5b interacts with complement C6, C7, C8 and C9 in a sequential and non-catalyzed manner to result in the formation of Terminal Complement Complex (TCC) [https://doi.org/10.1074/jbc.M111.219766]. The entire network is considered as a simple recognition and elimination system of host-immune complexes and apoptotic and/or pathogens, and therefore promotes host immune homeostasis. The complement system is also involved in cross-talk with other processes related to coagulation, lipid metabolism and cancer. However, many pathogens counteract complement attack through a range of different mechanisms, such acquisition of host complement regulators to the surface of pathogen, or secretion of complement inactivation factors. In order to have a holistic view of the entire complement network, Dr. John D.Lambris group (University of Pennsylvania) developed the Complement Map Database (CMAP) which is a unique repository focused on documented molecular interactions described within the complement cascade and between complement and other biological systems. Information contained in CMAP (http://www.complement.us/cmap/index.php)[https://doi.org/10.1093/bioinformatics/btt269] is entirely based on published experimental data and is fully revised by experts in the field. Further, the Signaling Gateway Molecule Pages -SGMP-( https://escholarship.org/uc/molecule_pages)[https://doi.org/10.1093/bioinformatics/btr190] has published a curated data on each protein involved in human complement activation pathways (refs. [https://doi.org/10.6072/H0.MP.A004235.01] [https://doi.org/10.6072/H0.MP.A004228.01] [https://doi.org/10.6072/H0.MP.A004276.01] [https://doi.org/10.6072/H0.MP.A004256.01] [https://doi.org/10.6072/H0.MP.A004240.01] [https://doi.org/10.6072/H0.MP.A008392.01] [https://doi.org/10.6072/H0.MP.A008391.01] [https://doi.org/10.6072/H0.MP.A004274.01] [https://doi.org/10.6072/H0.MP.A004275.01] [https://doi.org/10.6072/H0.MP.A004266.01] [https://doi.org/10.6072/H0.MP.A004267.01] [https://doi.org/10.6072/H0.MP.A004263.01] [https://doi.org/10.6072/H0.MP.A004234.01] [https://doi.org/10.6072/H0.MP.A004258.01] ).
Authors
Elisa Cirillo , Ashok R. Dinasarapu , Anwesha Bohler , Kristina Hanspers , Egon Willighagen , Friederike Ehrhart , Martina Summer-Kutmon , Alex Pico , Anders Riutta , Denise Slenter , Eric Weitz , Lars Willighagen , and Shuya IkedaActivity
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Cited In
- Looking for pathways related to COVID-19: confirmation of pathogenic mechanisms by SARS-CoV-2–host interactome (2021).
- Assessing the Contribution of Relative Macrophage Frequencies to Subcutaneous Adipose Tissue (2021).
- Long Term Culture of the A549 Cancer Cell Line Promotes Multilamellar Body Formation and Differentiation towards an Alveolar Type II Pneumocyte Phenotype (2016).
- Acute and chronic blood serum proteome changes in patients with methanol poisoning (2022).
- Discovering Common Pathogenic Mechanisms of COVID-19 and Parkinson Disease: An Integrated Bioinformatics Analysis (2022).
- Construction and analysis of protein-protein interaction network of non-alcoholic fatty liver disease.
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Organisms
Homo sapiensCommunities
Annotations
Pathway Ontology
complement system pathwayLabel | Type | Compact URI | Comment |
---|---|---|---|
beta-Glucan | Metabolite | chebi:28793 | |
LTA | Metabolite | chebi:28640 | |
fMLP | Metabolite | chebi:53490 | |
Heparin | Metabolite | chebi:28304 | |
HS | Metabolite | chebi:28815 | |
HSV-gC | GeneProduct | ncbigene:2703410 | |
FnBPA | GeneProduct | ncbigene:3913735 | |
CD16a | GeneProduct | ensembl:ENSG00000203747 | |
IBSP | GeneProduct | ensembl:ENSG00000029559 | |
C4a | GeneProduct | ncbigene:720 | |
SELE | GeneProduct | ensembl:ENSG00000007908 | |
C3b | GeneProduct | uniprot:P01024 | |
RgpA | GeneProduct | ncbiprotein:6330747 | Gngipain-1 |
C4BP | GeneProduct | ensembl:ENSG00000123838 | Two isoforms exists (C4BPA and C4BPB). |
ITGA2 | GeneProduct | ensembl:ENSG00000164171 | |
CR2 | GeneProduct | ensembl:ENSG00000117322 | |
DCN | GeneProduct | ensembl:ENSG00000011465 | |
FPR1 | GeneProduct | ensembl:ENSG00000171051 | |
ClfB | GeneProduct | ncbigene:5331889 | |
KLKB1 | GeneProduct | ensembl:ENSG00000164344 | |
Efb | GeneProduct | ncbigene:3238454 | |
OmpK36 | GeneProduct | uniprot:A0A0H3H0Y2 | |
ARRB2 | GeneProduct | ensembl:ENSG00000141480 | |
gC1qR | GeneProduct | ensembl:ENSG00000108561 | |
Protein-A | GeneProduct | ncbigene:5332074 | |
DAF | GeneProduct | ensembl:ENSG00000196352 | |
FGB | GeneProduct | ncbigene:2244 | |
FnBPB | GeneProduct | ncbigene:3913823 | |
C5aR1 | GeneProduct | ensembl:ENSG00000197405 | |
SSL7 | GeneProduct | ncbigene:2859139 | |
C3aR1 | GeneProduct | ensembl:ENSG00000171860 | |
LAMA5 | GeneProduct | ensembl:ENSG00000130702 | |
LfhA | GeneProduct | ncbigene:AAN47894 | |
CK | GeneProduct | ensembl:ENSG00000113712 | |
Ehp | GeneProduct | uniprot:A0A0H3K2R1 | |
CFHR1 | GeneProduct | ensembl:ENSG00000080910 | |
gp350 | GeneProduct | uniprot:P68343 | |
C3a-desArg | GeneProduct | ncbigene:718 | |
C5 | GeneProduct | ncbigene:727 | Complement C5 |
C3d | GeneProduct | ncbigene:718 | |
CPN | GeneProduct | ensembl:ENSG00000120054 | |
TLR2 | GeneProduct | ncbigene:7097 | |
SELP | GeneProduct | ensembl:ENSG00000174175 | |
C7 | GeneProduct | ensembl:ENSG00000112936 | |
FGA | GeneProduct | ncbigene:2243 | |
PTX3 | GeneProduct | ensembl:ENSG00000163661 | |
CbpA | GeneProduct | ncbigene:933487 | |
Protein-S | GeneProduct | ensembl:ENSG00000184500 | |
SFTPA2 | GeneProduct | ensembl:ENSG00000185303 | |
C9 | GeneProduct | ensembl:ENSG00000113600 | |
C1s | GeneProduct | ensembl:ENSG00000182326 | |
C6 | GeneProduct | ensembl:ENSG00000039537 | |
PrP | GeneProduct | ensembl:ENSG00000171867 | |
C1r | GeneProduct | uniprot:P00736 | |
ClfA | GeneProduct | ncbigene:2859231 | |
CD40 | GeneProduct | ensembl:ENSG00000101017 | |
OPN | GeneProduct | ensembl:ENSG00000118785 | |
Sfb | GeneProduct | ncbigene:3573107 | |
cC1qR | GeneProduct | ensembl:ENSG00000179218 | |
C3a | GeneProduct | ncbigene:718 | |
C1INH | GeneProduct | ensembl:ENSG00000149131 | |
CD59 | GeneProduct | ensembl:ENSG00000085063 | |
MBL2 | GeneProduct | ensembl:ENSG00000165471 | |
StcE | GeneProduct | uniprot:O82882 | |
C5a-desArg | GeneProduct | ncbigene:727 | |
ICAM2 | GeneProduct | ensembl:ENSG00000108622 | |
VCP | GeneProduct | ncbigene:3707640 | |
GNA15 | GeneProduct | ensembl:ENSG00000060558 | |
C3c | GeneProduct | ncbigene:718 | Peptide fragment from complement C3 |
WAS | GeneProduct | ensembl:ENSG00000015285 | |
ALB | GeneProduct | ensembl:ENSG00000163631 | |
THBS | GeneProduct | ensembl:ENSG00000137801 | |
SIC | GeneProduct | ncbigene:269972 | |
CD23 | GeneProduct | ensembl:ENSG00000104921 | |
C4b | GeneProduct | ncbigene:720 | |
SELPLG | GeneProduct | ensembl:ENSG00000110876 | |
FGG | GeneProduct | ensembl:ENSG00000171557 | |
SSL10 | GeneProduct | ncbigene:2859141 | |
SCP | GeneProduct | ncbiprotein:1030336 | Streptococcal C5a peptidase |
CFHR4 | GeneProduct | ensembl:ENSG00000134365 | |
GNAI2 | GeneProduct | ensembl:ENSG00000114353 | |
MAp44 | GeneProduct | ncbigene:5648 | |
PKC | GeneProduct | ensembl:ENSG00000154229 | |
FXIIa | GeneProduct | uniprot:P00748 | |
C5L2 | GeneProduct | ensembl:ENSG00000134830 | |
CFP | GeneProduct | ensembl:ENSG00000126759 | |
HIV-gp41 | GeneProduct | ncbigene:155971 | |
C1qRp | GeneProduct | ensembl:ENSG00000125810 | |
ITGB3 | GeneProduct | ensembl:ENSG00000259207 | |
CD19 | GeneProduct | ensembl:ENSG00000177455 | |
TXN | GeneProduct | ensembl:ENSG00000136810 | |
SSL5 | GeneProduct | ncbigene:2859140 | |
OMCI | GeneProduct | uniprot:Q5YD59 | |
FCN2 | GeneProduct | ensembl:ENSG00000160339 | |
ITGA2B | GeneProduct | ensembl:ENSG00000005961 | |
ELANE | GeneProduct | ensembl:ENSG00000197561 | |
iC3b | GeneProduct | uniprot:P01024 | Peptide fragment from complement C3 |
C4-A | GeneProduct | ncbigene:720 | Complement C4 exists in two isoforms, C4-A and C4-B. |
A2M | GeneProduct | ensembl:ENSG00000175899 | |
Skp | GeneProduct | uniprot:P0AEU7 | |
CFB | GeneProduct | hgnc:1037 | |
FXIII | GeneProduct | ensembl:ENSG00000124491 | |
PLAUR | GeneProduct | ensembl:ENSG00000011422 | |
PKA | GeneProduct | ensembl:ENSG00000072062 | |
GNA1870 | GeneProduct | ncbigene:12393750 | |
C3f | GeneProduct | ncbigene:718 | Peptide fragment from complement C3 |
ICAM1 | GeneProduct | ensembl:ENSG00000090339 | |
MASP1 | GeneProduct | ensembl:ENSG00000127241 | |
C2 | GeneProduct | ensembl:ENSG00000166278 | |
Protein M | GeneProduct | ncbiprotein:2940887 | |
VTN | GeneProduct | ensembl:ENSG00000109072 | |
CFH | GeneProduct | ensembl:ENSG00000000971 | |
FXIa | GeneProduct | uniprot:P03951 | |
PLG | GeneProduct | ensembl:ENSG00000122194 | |
Sbi | GeneProduct | ncbigene:5331420 | |
FGA | GeneProduct | ensembl:ENSG00000171560 | |
SAP | GeneProduct | ensembl:ENSG00000132703 | |
ADM | GeneProduct | ensembl:ENSG00000148926 | |
C8 | GeneProduct | ensembl:ENSG00000157131 | Complement C8 exhists in 3 isoforms. |
CLEC4M | GeneProduct | ensembl:ENSG00000104938 | |
CHIPS | GeneProduct | ncbigene:5332454 | |
SSL11 | GeneProduct | ncbigene:1123177 | |
FX | GeneProduct | ensembl:ENSG00000126218 | |
RPS19 | GeneProduct | ensembl:ENSG00000105372 | |
C3 | GeneProduct | ensembl:ENSG00000125730 | |
MAp19 | GeneProduct | ncbigene:10747 | |
SCIN | GeneProduct | ensembl:ENSG00000106804 | |
GNAI3 | GeneProduct | ensembl:ENSG00000065135 | |
APOA1 | GeneProduct | ensembl:ENSG00000118137 | |
E-LDL | GeneProduct | ensembl:ENSG00000173486 | |
CR1 | GeneProduct | ensembl:ENSG00000203710 | |
C3(H2O) | GeneProduct | ncbigene:629 | |
FCN1 | GeneProduct | ensembl:ENSG00000085265 | |
FGB | GeneProduct | ensembl:ENSG00000171564 | |
SELL | GeneProduct | ensembl:ENSG00000188404 | |
CFI | GeneProduct | ensembl:ENSG00000205403 | |
LAMB1 | GeneProduct | ensembl:ENSG00000091136 | |
FKBP13 | GeneProduct | ensembl:ENSG00000173486 | |
SFTPA1 | GeneProduct | ensembl:ENSG00000122852 | |
LAMC1 | GeneProduct | ensembl:ENSG00000135862 | |
LRP2 | GeneProduct | ensembl:ENSG00000081479 | |
C4a-desArg | GeneProduct | ncbigene:720 | |
MCP | GeneProduct | ensembl:ENSG00000117335 | |
CRP | GeneProduct | ensembl:ENSG00000132693 | |
CRIg | GeneProduct | ensembl:ENSG00000155659 | |
FN | GeneProduct | ensembl:ENSG0000011541 | |
CFD | GeneProduct | ensembl:ENSG00000197766 | Complement Factor D |
ADIPOQ | GeneProduct | ensembl:ENSG00000181092 | |
CPB2 | GeneProduct | ensembl:ENSG00000120054 | |
CFD | GeneProduct | ensembl:ENSG00000197766 | |
Ehp | GeneProduct | ncbigene:YP_043213 | |
C3d | GeneProduct | ncbigene:718 | Peptide fragment from complement C3 |
LfhA | GeneProduct | uniprot:Q47153 | |
C5 | GeneProduct | ncbigene:727 | |
C5a | GeneProduct | ncbigene:727 | |
C5b | GeneProduct | ncbigene:727 |
References
- Complement C1q subcomponent subunit A [Internet]. Chandrasekhar. UCSD Signaling Gateway Molecule Pages; 2012. Available from: http://www.signaling-gateway.org/molecule/query?afcsid=A004228 DOI Scholia
- Complement C2 [Internet]. Dinasarapu AR. UCSD Signaling Gateway Molecule Pages; 2013. Available from: http://www.signaling-gateway.org/molecule/query?afcsid=A004234 DOI Scholia
- Complement C3 [Internet]. Dinasarapu. UCSD Signaling Gateway Molecule Pages; 2012. Available from: http://www.signaling-gateway.org/molecule/query?afcsid=A004235 DOI Scholia
- Complement C5 [Internet]. Chandrasekhar. UCSD Signaling Gateway Molecule Pages; 2012. Available from: http://www.signaling-gateway.org/molecule/query?afcsid=A004240 DOI Scholia
- Complement factor H [Internet]. Dinasarapu AR. UCSD Signaling Gateway Molecule Pages; 2012. Available from: http://www.signaling-gateway.org/molecule/query?afcsid=A004256 DOI Scholia
- Properdin [Internet]. Min J. UCSD Signaling Gateway Molecule Pages; 2014. Available from: http://www.signaling-gateway.org/molecule/query?afcsid=A004258 DOI Scholia
- Integrin beta-2 [Internet]. Dinasarapu AR. UCSD Signaling Gateway Molecule Pages; 2013. Available from: http://www.signaling-gateway.org/molecule/query?afcsid=A004263 DOI Scholia
- L-Ficolin [Internet]. Chandrasekhar A. UCSD Signaling Gateway Molecule Pages; 2013. Available from: http://www.signaling-gateway.org/molecule/query?afcsid=A004266 DOI Scholia
- H-Ficolin [Internet]. Chandrasekhar A. UCSD Signaling Gateway; 2013. Available from: http://www.signaling-gateway.org/molecule/query?afcsid=A004267 DOI Scholia
- MASP-1 [Internet]. Chandrasekhar A. UCSD Signaling Gateway Molecule Pages; 2013. Available from: http://www.signaling-gateway.org/molecule/query?afcsid=A004274 DOI Scholia
- MASP-2 [Internet]. Chandrasekhar A. UCSD Signaling Gateway Molecule Pages; 2013. Available from: http://www.signaling-gateway.org/molecule/query?afcsid=A004275 DOI Scholia
- Mannose/mannan-binding lectin [Internet]. Dinasarapu AR. UCSD Signaling Gateway Molecule Pages; 2013. Available from: http://www.signaling-gateway.org/molecule/query?afcsid=A004276 DOI Scholia
- MASP-3 [Internet]. Chandrasekhar A. UCSD Signaling Gateway Molecule Pages; 2013. Available from: http://www.signaling-gateway.org/molecule/query?afcsid=A008391 DOI Scholia
- MAp44 [Internet]. Chandrasekhar A. UCSD Signaling Gateway Molecule Pages; 2013. Available from: http://www.signaling-gateway.org/molecule/query?afcsid=A008392 DOI Scholia
- C1q: structure, function, and receptors. Kishore U, Reid KB. Immunopharmacology. 2000 Aug;49(1–2):159–70. PubMed Europe PMC Scholia
- Complement: a key system for immune surveillance and homeostasis. Ricklin D, Hajishengallis G, Yang K, Lambris JD. Nat Immunol. 2010 Sep;11(9):785–97. PubMed Europe PMC Scholia
- Signaling gateway molecule pages--a data model perspective. Dinasarapu AR, Saunders B, Ozerlat I, Azam K, Subramaniam S. Bioinformatics. 2011 Jun 15;27(12):1736–8. PubMed Europe PMC Scholia
- CMAP: Complement Map Database. Yang K, Dinasarapu AR, Reis ES, Deangelis RA, Ricklin D, Subramaniam S, et al. Bioinformatics. 2013 Jul 15;29(14):1832–3. PubMed Europe PMC Scholia