#ID(s) interactor A	ID(s) interactor B	Alt. ID(s) interactor A	Alt. ID(s) interactor B	Alias(es) interactor A	Alias(es) interactor B	Interaction detection method(s)	Publication 1st author(s)	Publication Identifier(s)	Taxid interactor A	Taxid interactor B	Interaction type(s)	Source database(s)	Interaction identifier(s)	Confidence value(s)	Expansion method(s)	Biological role(s) interactor A	Biological role(s) interactor B	Experimental role(s) interactor A	Experimental role(s) interactor B	Type(s) interactor A	Type(s) interactor B	Xref(s) interactor A	Xref(s) interactor B	Interaction Xref(s)	Annotation(s) interactor A	Annotation(s) interactor B	Interaction annotation(s)	Host organism(s)	Interaction parameter(s)	Creation date	Update date	Checksum(s) interactor A	Checksum(s) interactor B	Interaction Checksum(s)	Negative	Feature(s) interactor A	Feature(s) interactor B	Stoichiometry(s) interactor A	Stoichiometry(s) interactor B	Identification method participant A	Identification method participant B
uniprotkb:P08603	matrixdb:MULT_84_human	intact:EBI-1223708|uniprotkb:A5PL14|uniprotkb:Q2TAZ5|uniprotkb:P78435|uniprotkb:Q14570|uniprotkb:Q38G77|uniprotkb:Q5TFM3|uniprotkb:Q8N708|uniprotkb:Q9NU86|ensembl:ENSP00000356399	intact:EBI-12735745|wwpdb:5fo7|wwpdb:3g6j|wwpdb:2i07|reactome:R-HSA-166832	psi-mi:cfah_human(display_long)|uniprotkb:CFH(gene name)|psi-mi:CFH(display_short)|uniprotkb:HF(gene name synonym)|uniprotkb:HF1(gene name synonym)|uniprotkb:HF2(gene name synonym)|uniprotkb:H factor 1(gene name synonym)	psi-mi:c3b_human(display_short)|psi-mi:MULT_84_human(display_long)|intact:Complement C3b complex(complex recommended name)|intact:C3b dimer(complex systematic name)	psi-mi:"MI:0028"(cosedimentation in solution)	Hakobyan et al. (2008)	pubmed:18786923|imex:IM-27484	taxid:9606(human)|taxid:9606(Homo sapiens)	taxid:9606(human)|taxid:9606(Homo sapiens)	psi-mi:"MI:0915"(physical association)	psi-mi:"MI:0469"(IntAct)	intact:EBI-22196011|imex:IM-27484-1	-	-	psi-mi:"MI:0499"(unspecified role)	psi-mi:"MI:0499"(unspecified role)	psi-mi:"MI:0497"(neutral component)	psi-mi:"MI:0497"(neutral component)	psi-mi:"MI:0326"(protein)	psi-mi:"MI:1302"(stable complex)	refseq:NP_000177.2|dip:DIP-38303N|ensembl:ENSG00000000971(gene)|ensembl:ENST00000367429(transcript)|go:"GO:0005576"(extracellular region)|go:"GO:0005615"(extracellular space)|go:"GO:0006956"(complement activation)|go:"GO:0006957"(complement activation, alternative pathway)|go:"GO:0008201"(heparin binding)|go:"GO:0030449"(regulation of complement activation)|go:"GO:0042802"(identical protein binding)|go:"GO:0043395"(heparan sulfate proteoglycan binding)|go:"GO:0070062"(extracellular exosome)|go:"GO:0072562"(blood microparticle)|go:"GO:1903659"(regulation of complement-dependent cytotoxicity)|interpro:IPR000436(Sushi/SCR/CCP)|interpro:IPR035976|mint:P08603|rcsb pdb:1FHC|rcsb pdb:1HAQ|rcsb pdb:1HCC|rcsb pdb:1HFH|rcsb pdb:1HFI|rcsb pdb:1KOV|rcsb pdb:2QFH|rcsb pdb:2RLP|rcsb pdb:2RLQ|rcsb pdb:2UWN|rcsb pdb:2V8E|rcsb pdb:2W80|rcsb pdb:2BZM|rcsb pdb:2G7I|rcsb pdb:2W81|rcsb pdb:2WII|rcsb pdb:2XQW|rcsb pdb:3GAU|rcsb pdb:3GAV|rcsb pdb:3GAW|rcsb pdb:3KXV|rcsb pdb:3KZJ|rcsb pdb:3OXU|rcsb pdb:3R62|rcsb pdb:3RJ3|rcsb pdb:3SW0|rcsb pdb:4AYD|rcsb pdb:4AYE|rcsb pdb:4AYI|rcsb pdb:4AYM|rcsb pdb:4B2R|rcsb pdb:4B2S|rcsb pdb:2IC4|rcsb pdb:2JGW|rcsb pdb:2JGX|rcsb pdb:4J38|rcsb pdb:4K12|rcsb pdb:4ONT|rcsb pdb:4ZH1|rcsb pdb:5NBQ|rcsb pdb:5O32|rcsb pdb:5O35|rcsb pdb:2KMS|rcsb pdb:2QFG|rcsb pdb:5WTB|rcsb pdb:6ATG|reactome:R-HSA-977606	pubmed:27782329(see-also)|pubmed:6225800(see-also)|evidence ontology:"ECO:0000353"|efo:"Orphanet:280133"(see-also)|efo:"Orphanet:2134"(see-also)|efo:"Orphanet:93575"(see-also)|efo:"EFO:0001365"(see-also)|pubmed:27013439(see-also)|pubmed:19196712(see-also)|pubmed:17051160(see-also)|go:"GO:0005615"(extracellular space)|go:"GO:0001848"(complement binding)|go:"GO:1903028"(positive regulation of opsonization)|go:"GO:0006956"(complement activation)|go:"GO:0050766"(positive regulation of phagocytosis)|go:"GO:0044533"(positive regulation of apoptotic process in another organism)|go:"GO:0050778"(positive regulation of immune response)|go:"GO:0030449"(regulation of complement activation)|go:"GO:0008228"(opsonization)|pubmed:6559201(see-also)|pubmed:15454921(see-also)|pubmed:21205667(see-also)|pubmed:17051150(see-also)|complex portal:CPX-973(complex-primary)|pubmed:26489954(see-also)	-	-	curated-complex:"A protein complex of the alternative pathway of complement activation of the innate immune system. Complement C3 precurser is activated by cleavage into C3a and C3b by C3 convertases, either C4bC2a in the classical and lectin pathways or C3(H2O)Bb, C3bBb, C3bBbC3b, C3bBbP or C3bBbC3bP in the alternative pathway.     C3b acts as an opsonin and interacts with glycoproteins and carbohydrates on pathogenic or apoptotic target cell surfaces through its reactive thioester moiety. Opsonization of target cells leads to enhanced phagocytosis, lysis of target cells via membrane attack complex (CPX-6159) assembly, clearance of antibody-antigen complexes and up-regulation of the adaptive response.     Activation of C3b leads to an amplification cascade that generates more C3 convertase, deposits more C3b at the local site and switches C3 convertases to C5 convertases.     To protect host cells from inadvertent complement activation the activation of C3b is tightly regulated by either disrupting the C3 convertases or aiding in the proteolytic degradation of C3b. Bacteria and viruses possess C3b proteases to evade the complement response.     Lack of protection, due to familial mutations in the complement genes or the presence of autoantibodies against regulators has been linked to atypical hemolytic uremic syndrome (aHUS) and C3 glomerulopathies (C3G) in kidneys and age-related macular degeneration (AMD) in eyes. Conditions of chronic and acute inflammations, as in rheumatoid arthritis, strokes, and heart attacks, become aggravated by complement activation against the disturbed tissue."|complex-properties:"The alternative pathway is continuously activated at a low level. C3 precursor is first processed by the removal of 4 Arg residues and spontaneous hydrolysis due to the breakdown of the internal thioester bond forms C3(H2O) (disulfide bonded P01024-PRO_0000005909 & P01024-PRO_0000005908).     C3(H2O) subsequently binds factor B that is cleaved by Factor D (P00746) into 2 fragments: CFBa and CFBb. CFBb, a serine protease, then combines with complement factor C3(H2O) or C3b to generate the C3 or C5 convertases.     Proteolytic cleavage of C3 to C3b is accompanied by large conformational changes that result in the exposure of cryptic binding sites required for convertase assembly and regulation. This includes a significant movement of the thioester-bond-containing domain through which C3b attaches to target surfaces."|complex-assembly:Heterodimer|disease:"Complement component 3 (C3) deficiency [Orphanet:280133]: a rare, autosomal recessive defect of the complement classical pathway. Patients develop recurrent, severe, pyogenic infections because of ineffective opsonization of pathogens. Some patients may also develop autoimmune disorders, such as arthralgia and vasculitic rashes, lupus-like syndrome and membranoproliferative glomerulonephritis."|disease:"Atypical hemolytic-uremic syndrome with C3 anomaly [Orphanet:2134 & Orphanet:93575]: an autosomal dominant, atypical form of hemolytic-uremic syndrome (aHUS, a thrombotic microangiopathy) characterized by mechanical hemolytic anemia, thrombocytopenia, and renal dysfunction."|disease:"Age-related macular degeneration [EFO:0001365]: age-related macular degeneration usually in older adults which results in a loss of vision in the center of the visual field (the macula lutea) because of damage to the retina. Manifests as ophthalmoscopically visible yellowish accumulations of protein and lipid that lie beneath the retinal pigment epithelium and within an elastin-containing structure known as Bruch membrane. Occurs in dry and wet forms. Most common cause of irreversible vision loss in the developed world."	figure legend:2D|full coverage:Only protein-protein interactions|curation depth:imex curation	taxid:-1(in vitro)|taxid:-1(In vitro)	-	2019/10/24	2019/11/12	rogid:1mjo+AJLIQnEsMFqsGsmUFbfUxk9606	-	-	false	mutation decreasing interaction strength:402-402	-	-	-	psi-mi:"MI:0396"(predetermined participant)	psi-mi:"MI:0396"(predetermined participant)
uniprotkb:P08603	uniprotkb:P02741	intact:EBI-1223708|uniprotkb:A5PL14|uniprotkb:Q2TAZ5|uniprotkb:P78435|uniprotkb:Q14570|uniprotkb:Q38G77|uniprotkb:Q5TFM3|uniprotkb:Q8N708|uniprotkb:Q9NU86|ensembl:ENSP00000356399	intact:EBI-1395983|uniprotkb:A8K078|uniprotkb:Q08AK3|uniprotkb:Q8WW75|uniprotkb:D3DVD9|uniprotkb:D3DVE0|ensembl:ENSP00000255030	psi-mi:cfah_human(display_long)|uniprotkb:CFH(gene name)|psi-mi:CFH(display_short)|uniprotkb:HF(gene name synonym)|uniprotkb:HF1(gene name synonym)|uniprotkb:HF2(gene name synonym)|uniprotkb:H factor 1(gene name synonym)	psi-mi:crp_human(display_long)|uniprotkb:CRP(gene name)|psi-mi:CRP(display_short)|uniprotkb:PTX1(gene name synonym)	psi-mi:"MI:0411"(enzyme linked immunosorbent assay)	Hakobyan et al. (2008)	pubmed:18786923|imex:IM-27484	taxid:9606(human)|taxid:9606(Homo sapiens)	taxid:9606(human)|taxid:9606(Homo sapiens)	psi-mi:"MI:0407"(direct interaction)	psi-mi:"MI:0469"(IntAct)	intact:EBI-22196033|imex:IM-27484-3	-	-	psi-mi:"MI:0499"(unspecified role)	psi-mi:"MI:0499"(unspecified role)	psi-mi:"MI:0498"(prey)	psi-mi:"MI:0496"(bait)	psi-mi:"MI:0326"(protein)	psi-mi:"MI:0326"(protein)	refseq:NP_000177.2|dip:DIP-38303N|ensembl:ENSG00000000971(gene)|ensembl:ENST00000367429(transcript)|go:"GO:0005576"(extracellular region)|go:"GO:0005615"(extracellular space)|go:"GO:0006956"(complement activation)|go:"GO:0006957"(complement activation, alternative pathway)|go:"GO:0008201"(heparin binding)|go:"GO:0030449"(regulation of complement activation)|go:"GO:0042802"(identical protein binding)|go:"GO:0043395"(heparan sulfate proteoglycan binding)|go:"GO:0070062"(extracellular exosome)|go:"GO:0072562"(blood microparticle)|go:"GO:1903659"(regulation of complement-dependent cytotoxicity)|interpro:IPR000436(Sushi/SCR/CCP)|interpro:IPR035976|mint:P08603|rcsb pdb:1FHC|rcsb pdb:1HAQ|rcsb pdb:1HCC|rcsb pdb:1HFH|rcsb pdb:1HFI|rcsb pdb:1KOV|rcsb pdb:2QFH|rcsb pdb:2RLP|rcsb pdb:2RLQ|rcsb pdb:2UWN|rcsb pdb:2V8E|rcsb pdb:2W80|rcsb pdb:2BZM|rcsb pdb:2G7I|rcsb pdb:2W81|rcsb pdb:2WII|rcsb pdb:2XQW|rcsb pdb:3GAU|rcsb pdb:3GAV|rcsb pdb:3GAW|rcsb pdb:3KXV|rcsb pdb:3KZJ|rcsb pdb:3OXU|rcsb pdb:3R62|rcsb pdb:3RJ3|rcsb pdb:3SW0|rcsb pdb:4AYD|rcsb pdb:4AYE|rcsb pdb:4AYI|rcsb pdb:4AYM|rcsb pdb:4B2R|rcsb pdb:4B2S|rcsb pdb:2IC4|rcsb pdb:2JGW|rcsb pdb:2JGX|rcsb pdb:4J38|rcsb pdb:4K12|rcsb pdb:4ONT|rcsb pdb:4ZH1|rcsb pdb:5NBQ|rcsb pdb:5O32|rcsb pdb:5O35|rcsb pdb:2KMS|rcsb pdb:2QFG|rcsb pdb:5WTB|rcsb pdb:6ATG|reactome:R-HSA-977606	refseq:NP_000558.2|refseq:NP_001315986.1|refseq:NP_001315987.1|dip:DIP-39125N|ensembl:ENSG00000132693(gene)|ensembl:ENST00000255030(transcript)|go:"GO:0001849"(complement component C1q complex binding)|go:"GO:0005509"(calcium ion binding)|go:"GO:0005576"(extracellular region)|go:"GO:0005615"(extracellular space)|go:"GO:0006953"(acute-phase response)|go:"GO:0006954"(inflammatory response)|go:"GO:0006958"(complement activation, classical pathway)|go:"GO:0008228"(opsonization)|go:"GO:0010628"(positive regulation of gene expression)|go:"GO:0010745"(negative regulation of macrophage derived foam cell differentiation)|go:"GO:0010888"(negative regulation of lipid storage)|go:"GO:0030169"(low-density lipoprotein particle binding)|go:"GO:0032677"(regulation of interleukin-8 production)|go:"GO:0032930"(positive regulation of superoxide anion generation)|go:"GO:0032945"(negative regulation of mononuclear cell proliferation)|go:"GO:0033265"(choline binding)|go:"GO:0042310"(vasoconstriction)|go:"GO:0042802"(identical protein binding)|go:"GO:0044793"(negative regulation by host of viral process)|go:"GO:0045087"(innate immune response)|go:"GO:0050750"(low-density lipoprotein particle receptor binding)|go:"GO:0050830"(defense response to Gram-positive bacterium)|interpro:IPR001759(Pentaxin)|interpro:IPR013320(Concanavalin A-like lectin/glucanase, subgroup)|interpro:IPR030476|mint:P02741|rcsb pdb:1B09|rcsb pdb:1CRV|rcsb pdb:1GNH|rcsb pdb:1LJ7|rcsb pdb:3L2Y|rcsb pdb:3PVN|rcsb pdb:3PVO|reactome:R-HSA-173623	-	-	-	figure legend:3 B/C|comment:CRP immobilized in the absence of Ca2+, or immobilized denatured CRP.|full coverage:Only protein-protein interactions|curation depth:imex curation	taxid:-1(in vitro)|taxid:-1(In vitro)	-	2019/10/24	2019/11/12	rogid:1mjo+AJLIQnEsMFqsGsmUFbfUxk9606	rogid:R7vKMSGKD4ETbUKVGL9IiL8jzjE9606	rigid:VO9cYbQbjRx+xzoHzUzCFjv6qpw	false	mutation with no effect:402-402	-	-	1	psi-mi:"MI:0421"(identification by antibody)	psi-mi:"MI:0421"(identification by antibody)
uniprotkb:P08603	uniprotkb:P02741	intact:EBI-1223708|uniprotkb:A5PL14|uniprotkb:Q2TAZ5|uniprotkb:P78435|uniprotkb:Q14570|uniprotkb:Q38G77|uniprotkb:Q5TFM3|uniprotkb:Q8N708|uniprotkb:Q9NU86|ensembl:ENSP00000356399	intact:EBI-1395983|uniprotkb:A8K078|uniprotkb:Q08AK3|uniprotkb:Q8WW75|uniprotkb:D3DVD9|uniprotkb:D3DVE0|ensembl:ENSP00000255030	psi-mi:cfah_human(display_long)|uniprotkb:CFH(gene name)|psi-mi:CFH(display_short)|uniprotkb:HF(gene name synonym)|uniprotkb:HF1(gene name synonym)|uniprotkb:HF2(gene name synonym)|uniprotkb:H factor 1(gene name synonym)	psi-mi:crp_human(display_long)|uniprotkb:CRP(gene name)|psi-mi:CRP(display_short)|uniprotkb:PTX1(gene name synonym)	psi-mi:"MI:0411"(enzyme linked immunosorbent assay)	Hakobyan et al. (2008)	pubmed:18786923|imex:IM-27484	taxid:9606(human)|taxid:9606(Homo sapiens)	taxid:9606(human)|taxid:9606(Homo sapiens)	psi-mi:"MI:0407"(direct interaction)	psi-mi:"MI:0469"(IntAct)	intact:EBI-22196064|imex:IM-27484-5	-	-	psi-mi:"MI:0499"(unspecified role)	psi-mi:"MI:0499"(unspecified role)	psi-mi:"MI:0496"(bait)	psi-mi:"MI:0496"(bait)	psi-mi:"MI:0326"(protein)	psi-mi:"MI:0326"(protein)	refseq:NP_000177.2|dip:DIP-38303N|ensembl:ENSG00000000971(gene)|ensembl:ENST00000367429(transcript)|go:"GO:0005576"(extracellular region)|go:"GO:0005615"(extracellular space)|go:"GO:0006956"(complement activation)|go:"GO:0006957"(complement activation, alternative pathway)|go:"GO:0008201"(heparin binding)|go:"GO:0030449"(regulation of complement activation)|go:"GO:0042802"(identical protein binding)|go:"GO:0043395"(heparan sulfate proteoglycan binding)|go:"GO:0070062"(extracellular exosome)|go:"GO:0072562"(blood microparticle)|go:"GO:1903659"(regulation of complement-dependent cytotoxicity)|interpro:IPR000436(Sushi/SCR/CCP)|interpro:IPR035976|mint:P08603|rcsb pdb:1FHC|rcsb pdb:1HAQ|rcsb pdb:1HCC|rcsb pdb:1HFH|rcsb pdb:1HFI|rcsb pdb:1KOV|rcsb pdb:2QFH|rcsb pdb:2RLP|rcsb pdb:2RLQ|rcsb pdb:2UWN|rcsb pdb:2V8E|rcsb pdb:2W80|rcsb pdb:2BZM|rcsb pdb:2G7I|rcsb pdb:2W81|rcsb pdb:2WII|rcsb pdb:2XQW|rcsb pdb:3GAU|rcsb pdb:3GAV|rcsb pdb:3GAW|rcsb pdb:3KXV|rcsb pdb:3KZJ|rcsb pdb:3OXU|rcsb pdb:3R62|rcsb pdb:3RJ3|rcsb pdb:3SW0|rcsb pdb:4AYD|rcsb pdb:4AYE|rcsb pdb:4AYI|rcsb pdb:4AYM|rcsb pdb:4B2R|rcsb pdb:4B2S|rcsb pdb:2IC4|rcsb pdb:2JGW|rcsb pdb:2JGX|rcsb pdb:4J38|rcsb pdb:4K12|rcsb pdb:4ONT|rcsb pdb:4ZH1|rcsb pdb:5NBQ|rcsb pdb:5O32|rcsb pdb:5O35|rcsb pdb:2KMS|rcsb pdb:2QFG|rcsb pdb:5WTB|rcsb pdb:6ATG|reactome:R-HSA-977606	refseq:NP_000558.2|refseq:NP_001315986.1|refseq:NP_001315987.1|dip:DIP-39125N|ensembl:ENSG00000132693(gene)|ensembl:ENST00000255030(transcript)|go:"GO:0001849"(complement component C1q complex binding)|go:"GO:0005509"(calcium ion binding)|go:"GO:0005576"(extracellular region)|go:"GO:0005615"(extracellular space)|go:"GO:0006953"(acute-phase response)|go:"GO:0006954"(inflammatory response)|go:"GO:0006958"(complement activation, classical pathway)|go:"GO:0008228"(opsonization)|go:"GO:0010628"(positive regulation of gene expression)|go:"GO:0010745"(negative regulation of macrophage derived foam cell differentiation)|go:"GO:0010888"(negative regulation of lipid storage)|go:"GO:0030169"(low-density lipoprotein particle binding)|go:"GO:0032677"(regulation of interleukin-8 production)|go:"GO:0032930"(positive regulation of superoxide anion generation)|go:"GO:0032945"(negative regulation of mononuclear cell proliferation)|go:"GO:0033265"(choline binding)|go:"GO:0042310"(vasoconstriction)|go:"GO:0042802"(identical protein binding)|go:"GO:0044793"(negative regulation by host of viral process)|go:"GO:0045087"(innate immune response)|go:"GO:0050750"(low-density lipoprotein particle receptor binding)|go:"GO:0050830"(defense response to Gram-positive bacterium)|interpro:IPR001759(Pentaxin)|interpro:IPR013320(Concanavalin A-like lectin/glucanase, subgroup)|interpro:IPR030476|mint:P02741|rcsb pdb:1B09|rcsb pdb:1CRV|rcsb pdb:1GNH|rcsb pdb:1LJ7|rcsb pdb:3L2Y|rcsb pdb:3PVN|rcsb pdb:3PVO|reactome:R-HSA-173623	-	-	-	figure legend:3 D|full coverage:Only protein-protein interactions|curation depth:imex curation	taxid:-1(in vitro)|taxid:-1(In vitro)	-	2019/10/24	2019/11/12	rogid:1mjo+AJLIQnEsMFqsGsmUFbfUxk9606	rogid:R7vKMSGKD4ETbUKVGL9IiL8jzjE9606	rigid:VO9cYbQbjRx+xzoHzUzCFjv6qpw	false	mutation decreasing interaction strength:402-402	-	-	1	psi-mi:"MI:0421"(identification by antibody)	psi-mi:"MI:0421"(identification by antibody)
uniprotkb:P08603	matrixdb:MULT_84_human	intact:EBI-1223708|uniprotkb:A5PL14|uniprotkb:Q2TAZ5|uniprotkb:P78435|uniprotkb:Q14570|uniprotkb:Q38G77|uniprotkb:Q5TFM3|uniprotkb:Q8N708|uniprotkb:Q9NU86|ensembl:ENSP00000356399	intact:EBI-12735745|wwpdb:5fo7|wwpdb:3g6j|wwpdb:2i07|reactome:R-HSA-166832	psi-mi:cfah_human(display_long)|uniprotkb:CFH(gene name)|psi-mi:CFH(display_short)|uniprotkb:HF(gene name synonym)|uniprotkb:HF1(gene name synonym)|uniprotkb:HF2(gene name synonym)|uniprotkb:H factor 1(gene name synonym)	psi-mi:c3b_human(display_short)|psi-mi:MULT_84_human(display_long)|intact:Complement C3b complex(complex recommended name)|intact:C3b dimer(complex systematic name)	psi-mi:"MI:0411"(enzyme linked immunosorbent assay)	Hakobyan et al. (2008)	pubmed:18786923|imex:IM-27484	taxid:9606(human)|taxid:9606(Homo sapiens)	taxid:9606(human)|taxid:9606(Homo sapiens)	psi-mi:"MI:0407"(direct interaction)	psi-mi:"MI:0469"(IntAct)	intact:EBI-22196072|imex:IM-27484-7	-	-	psi-mi:"MI:0499"(unspecified role)	psi-mi:"MI:0499"(unspecified role)	psi-mi:"MI:0496"(bait)	psi-mi:"MI:0496"(bait)	psi-mi:"MI:0326"(protein)	psi-mi:"MI:1302"(stable complex)	refseq:NP_000177.2|dip:DIP-38303N|ensembl:ENSG00000000971(gene)|ensembl:ENST00000367429(transcript)|go:"GO:0005576"(extracellular region)|go:"GO:0005615"(extracellular space)|go:"GO:0006956"(complement activation)|go:"GO:0006957"(complement activation, alternative pathway)|go:"GO:0008201"(heparin binding)|go:"GO:0030449"(regulation of complement activation)|go:"GO:0042802"(identical protein binding)|go:"GO:0043395"(heparan sulfate proteoglycan binding)|go:"GO:0070062"(extracellular exosome)|go:"GO:0072562"(blood microparticle)|go:"GO:1903659"(regulation of complement-dependent cytotoxicity)|interpro:IPR000436(Sushi/SCR/CCP)|interpro:IPR035976|mint:P08603|rcsb pdb:1FHC|rcsb pdb:1HAQ|rcsb pdb:1HCC|rcsb pdb:1HFH|rcsb pdb:1HFI|rcsb pdb:1KOV|rcsb pdb:2QFH|rcsb pdb:2RLP|rcsb pdb:2RLQ|rcsb pdb:2UWN|rcsb pdb:2V8E|rcsb pdb:2W80|rcsb pdb:2BZM|rcsb pdb:2G7I|rcsb pdb:2W81|rcsb pdb:2WII|rcsb pdb:2XQW|rcsb pdb:3GAU|rcsb pdb:3GAV|rcsb pdb:3GAW|rcsb pdb:3KXV|rcsb pdb:3KZJ|rcsb pdb:3OXU|rcsb pdb:3R62|rcsb pdb:3RJ3|rcsb pdb:3SW0|rcsb pdb:4AYD|rcsb pdb:4AYE|rcsb pdb:4AYI|rcsb pdb:4AYM|rcsb pdb:4B2R|rcsb pdb:4B2S|rcsb pdb:2IC4|rcsb pdb:2JGW|rcsb pdb:2JGX|rcsb pdb:4J38|rcsb pdb:4K12|rcsb pdb:4ONT|rcsb pdb:4ZH1|rcsb pdb:5NBQ|rcsb pdb:5O32|rcsb pdb:5O35|rcsb pdb:2KMS|rcsb pdb:2QFG|rcsb pdb:5WTB|rcsb pdb:6ATG|reactome:R-HSA-977606	pubmed:27782329(see-also)|pubmed:6225800(see-also)|evidence ontology:"ECO:0000353"|efo:"Orphanet:280133"(see-also)|efo:"Orphanet:2134"(see-also)|efo:"Orphanet:93575"(see-also)|efo:"EFO:0001365"(see-also)|pubmed:27013439(see-also)|pubmed:19196712(see-also)|pubmed:17051160(see-also)|go:"GO:0005615"(extracellular space)|go:"GO:0001848"(complement binding)|go:"GO:1903028"(positive regulation of opsonization)|go:"GO:0006956"(complement activation)|go:"GO:0050766"(positive regulation of phagocytosis)|go:"GO:0044533"(positive regulation of apoptotic process in another organism)|go:"GO:0050778"(positive regulation of immune response)|go:"GO:0030449"(regulation of complement activation)|go:"GO:0008228"(opsonization)|pubmed:6559201(see-also)|pubmed:15454921(see-also)|pubmed:21205667(see-also)|pubmed:17051150(see-also)|complex portal:CPX-973(complex-primary)|pubmed:26489954(see-also)	-	-	curated-complex:"A protein complex of the alternative pathway of complement activation of the innate immune system. Complement C3 precurser is activated by cleavage into C3a and C3b by C3 convertases, either C4bC2a in the classical and lectin pathways or C3(H2O)Bb, C3bBb, C3bBbC3b, C3bBbP or C3bBbC3bP in the alternative pathway.     C3b acts as an opsonin and interacts with glycoproteins and carbohydrates on pathogenic or apoptotic target cell surfaces through its reactive thioester moiety. Opsonization of target cells leads to enhanced phagocytosis, lysis of target cells via membrane attack complex (CPX-6159) assembly, clearance of antibody-antigen complexes and up-regulation of the adaptive response.     Activation of C3b leads to an amplification cascade that generates more C3 convertase, deposits more C3b at the local site and switches C3 convertases to C5 convertases.     To protect host cells from inadvertent complement activation the activation of C3b is tightly regulated by either disrupting the C3 convertases or aiding in the proteolytic degradation of C3b. Bacteria and viruses possess C3b proteases to evade the complement response.     Lack of protection, due to familial mutations in the complement genes or the presence of autoantibodies against regulators has been linked to atypical hemolytic uremic syndrome (aHUS) and C3 glomerulopathies (C3G) in kidneys and age-related macular degeneration (AMD) in eyes. Conditions of chronic and acute inflammations, as in rheumatoid arthritis, strokes, and heart attacks, become aggravated by complement activation against the disturbed tissue."|complex-properties:"The alternative pathway is continuously activated at a low level. C3 precursor is first processed by the removal of 4 Arg residues and spontaneous hydrolysis due to the breakdown of the internal thioester bond forms C3(H2O) (disulfide bonded P01024-PRO_0000005909 & P01024-PRO_0000005908).     C3(H2O) subsequently binds factor B that is cleaved by Factor D (P00746) into 2 fragments: CFBa and CFBb. CFBb, a serine protease, then combines with complement factor C3(H2O) or C3b to generate the C3 or C5 convertases.     Proteolytic cleavage of C3 to C3b is accompanied by large conformational changes that result in the exposure of cryptic binding sites required for convertase assembly and regulation. This includes a significant movement of the thioester-bond-containing domain through which C3b attaches to target surfaces."|complex-assembly:Heterodimer|disease:"Complement component 3 (C3) deficiency [Orphanet:280133]: a rare, autosomal recessive defect of the complement classical pathway. Patients develop recurrent, severe, pyogenic infections because of ineffective opsonization of pathogens. Some patients may also develop autoimmune disorders, such as arthralgia and vasculitic rashes, lupus-like syndrome and membranoproliferative glomerulonephritis."|disease:"Atypical hemolytic-uremic syndrome with C3 anomaly [Orphanet:2134 & Orphanet:93575]: an autosomal dominant, atypical form of hemolytic-uremic syndrome (aHUS, a thrombotic microangiopathy) characterized by mechanical hemolytic anemia, thrombocytopenia, and renal dysfunction."|disease:"Age-related macular degeneration [EFO:0001365]: age-related macular degeneration usually in older adults which results in a loss of vision in the center of the visual field (the macula lutea) because of damage to the retina. Manifests as ophthalmoscopically visible yellowish accumulations of protein and lipid that lie beneath the retinal pigment epithelium and within an elastin-containing structure known as Bruch membrane. Occurs in dry and wet forms. Most common cause of irreversible vision loss in the developed world."	figure legend:3 E|full coverage:Only protein-protein interactions|curation depth:imex curation	taxid:-1(in vitro)|taxid:-1(In vitro)	-	2019/10/24	2019/11/12	rogid:1mjo+AJLIQnEsMFqsGsmUFbfUxk9606	-	-	false	mutation decreasing interaction strength:402-402	-	-	-	psi-mi:"MI:0421"(identification by antibody)	psi-mi:"MI:0421"(identification by antibody)
uniprotkb:P02741	uniprotkb:P02741	intact:EBI-1395983|uniprotkb:A8K078|uniprotkb:Q08AK3|uniprotkb:Q8WW75|uniprotkb:D3DVD9|uniprotkb:D3DVE0|ensembl:ENSP00000255030	intact:EBI-1395983|uniprotkb:A8K078|uniprotkb:Q08AK3|uniprotkb:Q8WW75|uniprotkb:D3DVD9|uniprotkb:D3DVE0|ensembl:ENSP00000255030	psi-mi:crp_human(display_long)|uniprotkb:CRP(gene name)|psi-mi:CRP(display_short)|uniprotkb:PTX1(gene name synonym)	psi-mi:crp_human(display_long)|uniprotkb:CRP(gene name)|psi-mi:CRP(display_short)|uniprotkb:PTX1(gene name synonym)	psi-mi:"MI:0071"(molecular sieving)	Hakobyan et al. (2008)	pubmed:18786923|imex:IM-27484	taxid:9606(human)|taxid:9606(Homo sapiens)	taxid:9606(human)|taxid:9606(Homo sapiens)	psi-mi:"MI:0407"(direct interaction)	psi-mi:"MI:0469"(IntAct)	intact:EBI-22196102|imex:IM-27484-9	-	-	psi-mi:"MI:0499"(unspecified role)	psi-mi:"MI:0499"(unspecified role)	psi-mi:"MI:0497"(neutral component)	psi-mi:"MI:0497"(neutral component)	psi-mi:"MI:0326"(protein)	psi-mi:"MI:0326"(protein)	refseq:NP_000558.2|refseq:NP_001315986.1|refseq:NP_001315987.1|dip:DIP-39125N|ensembl:ENSG00000132693(gene)|ensembl:ENST00000255030(transcript)|go:"GO:0001849"(complement component C1q complex binding)|go:"GO:0005509"(calcium ion binding)|go:"GO:0005576"(extracellular region)|go:"GO:0005615"(extracellular space)|go:"GO:0006953"(acute-phase response)|go:"GO:0006954"(inflammatory response)|go:"GO:0006958"(complement activation, classical pathway)|go:"GO:0008228"(opsonization)|go:"GO:0010628"(positive regulation of gene expression)|go:"GO:0010745"(negative regulation of macrophage derived foam cell differentiation)|go:"GO:0010888"(negative regulation of lipid storage)|go:"GO:0030169"(low-density lipoprotein particle binding)|go:"GO:0032677"(regulation of interleukin-8 production)|go:"GO:0032930"(positive regulation of superoxide anion generation)|go:"GO:0032945"(negative regulation of mononuclear cell proliferation)|go:"GO:0033265"(choline binding)|go:"GO:0042310"(vasoconstriction)|go:"GO:0042802"(identical protein binding)|go:"GO:0044793"(negative regulation by host of viral process)|go:"GO:0045087"(innate immune response)|go:"GO:0050750"(low-density lipoprotein particle receptor binding)|go:"GO:0050830"(defense response to Gram-positive bacterium)|interpro:IPR001759(Pentaxin)|interpro:IPR013320(Concanavalin A-like lectin/glucanase, subgroup)|interpro:IPR030476|mint:P02741|rcsb pdb:1B09|rcsb pdb:1CRV|rcsb pdb:1GNH|rcsb pdb:1LJ7|rcsb pdb:3L2Y|rcsb pdb:3PVN|rcsb pdb:3PVO|reactome:R-HSA-173623	refseq:NP_000558.2|refseq:NP_001315986.1|refseq:NP_001315987.1|dip:DIP-39125N|ensembl:ENSG00000132693(gene)|ensembl:ENST00000255030(transcript)|go:"GO:0001849"(complement component C1q complex binding)|go:"GO:0005509"(calcium ion binding)|go:"GO:0005576"(extracellular region)|go:"GO:0005615"(extracellular space)|go:"GO:0006953"(acute-phase response)|go:"GO:0006954"(inflammatory response)|go:"GO:0006958"(complement activation, classical pathway)|go:"GO:0008228"(opsonization)|go:"GO:0010628"(positive regulation of gene expression)|go:"GO:0010745"(negative regulation of macrophage derived foam cell differentiation)|go:"GO:0010888"(negative regulation of lipid storage)|go:"GO:0030169"(low-density lipoprotein particle binding)|go:"GO:0032677"(regulation of interleukin-8 production)|go:"GO:0032930"(positive regulation of superoxide anion generation)|go:"GO:0032945"(negative regulation of mononuclear cell proliferation)|go:"GO:0033265"(choline binding)|go:"GO:0042310"(vasoconstriction)|go:"GO:0042802"(identical protein binding)|go:"GO:0044793"(negative regulation by host of viral process)|go:"GO:0045087"(innate immune response)|go:"GO:0050750"(low-density lipoprotein particle receptor binding)|go:"GO:0050830"(defense response to Gram-positive bacterium)|interpro:IPR001759(Pentaxin)|interpro:IPR013320(Concanavalin A-like lectin/glucanase, subgroup)|interpro:IPR030476|mint:P02741|rcsb pdb:1B09|rcsb pdb:1CRV|rcsb pdb:1GNH|rcsb pdb:1LJ7|rcsb pdb:3L2Y|rcsb pdb:3PVN|rcsb pdb:3PVO|reactome:R-HSA-173623	-	-	-	figure legend:4A|full coverage:Only protein-protein interactions|curation depth:imex curation	taxid:9606(human-blood)|taxid:9606(human blood)	-	2019/10/24	2019/11/12	rogid:R7vKMSGKD4ETbUKVGL9IiL8jzjE9606	rogid:R7vKMSGKD4ETbUKVGL9IiL8jzjE9606	rigid:R8InTlFX5wiVAjF7Gnb6JyhgM2M	false	125i radiolabel:?-?	125i radiolabel:?-?	5	0	psi-mi:"MI:0396"(predetermined participant)	psi-mi:"MI:0396"(predetermined participant)