2XRC | pdb_00002xrc

Human complement factor I

External Resource: Annotation

Domain Annotation: ECOD Classification
Domain Annotation: CATH
Protein Family Annotation
Gene Ontology: Gene Product Annotation
InterPro: Protein Family Classification
Pharos: Disease Associations

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
D		e2xrcD17	A: Subtilisin-like	X: Subtilisin-like	H: Subtilisin-like	T: Peptidase_M49	F:	ECOD (20:10:01)
D		e2xrcD6	A: HTH	X: HTH	H: winged helix domain	T: PI3K_C2	F:	ECOD (20:10:01)
D		e2xrcD1	A: RuvA-C	X: post-HMGL domain-like	H: post-HMGL domain-like	T: Ldl_recept_a	F:	ECOD (20:10:01)
C		e2xrcC17	A: Subtilisin-like	X: Subtilisin-like	H: Subtilisin-like	T: Peptidase_M49	F:	ECOD (20:10:01)
C		e2xrcC3	A: HTH	X: HTH	H: winged helix domain	T: PI3K_C2	F:	ECOD (20:10:01)
C		e2xrcC1	A: RuvA-C	X: post-HMGL domain-like	H: post-HMGL domain-like	T: Ldl_recept_a	F:	ECOD (20:10:01)
B		e2xrcB1	A: Single-stranded left-handed beta-helix	X: Immunoglobulin-related	H: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	T: CFAI_FIMAC_N	F:	ECOD (20:10:01)
B		e2xrcB2	A: Single-stranded left-handed beta-helix	X: Immunoglobulin-related	H: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	T: Pyr_redox_2	F:	ECOD (20:10:01)
B		e2xrcB3	A: HTH	X: HTH	H: winged helix domain	T: Trypsin	F:	ECOD (20:10:01)
A		e2xrcA11	A: Fusion glycoprotein F2	X: Fusion glycoprotein F2	H: Fusion glycoprotein F2	T: FERM_M	F:	ECOD (20:10:01)
A		e2xrcA1	A: RuvA-C	X: post-HMGL domain-like	H: post-HMGL domain-like	T: Ldl_recept_a	F:	ECOD (20:10:01)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
D	3.30.60.30	Alpha Beta	2-Layer Sandwich	Wheat Germ Agglutinin (Isolectin 2)	domain 1	CATH (4.3.0)
D	3.10.250.10	Alpha Beta	Roll	Mac-2 Binding Protein	SRCR-like domain	CATH (4.3.0)
D	2.40.10.10	Mainly Beta	Beta Barrel	Thrombin, subunit H	Trypsin-like serine proteases	CATH (4.3.0)
C	3.30.60.30	Alpha Beta	2-Layer Sandwich	Wheat Germ Agglutinin (Isolectin 2)	domain 1	CATH (4.3.0)
C	3.10.250.10	Alpha Beta	Roll	Mac-2 Binding Protein	SRCR-like domain	CATH (4.3.0)
C	2.40.10.10	Mainly Beta	Beta Barrel	Thrombin, subunit H	Trypsin-like serine proteases	CATH (4.3.0)
B	3.30.60.30	Alpha Beta	2-Layer Sandwich	Wheat Germ Agglutinin (Isolectin 2)	domain 1	CATH (4.3.0)
B	3.10.250.10	Alpha Beta	Roll	Mac-2 Binding Protein	SRCR-like domain	CATH (4.3.0)
B	2.40.10.10	Mainly Beta	Beta Barrel	Thrombin, subunit H	Trypsin-like serine proteases	CATH (4.3.0)
A	3.30.60.30	Alpha Beta	2-Layer Sandwich	Wheat Germ Agglutinin (Isolectin 2)	domain 1	CATH (4.3.0)
A	3.10.250.10	Alpha Beta	Roll	Mac-2 Binding Protein	SRCR-like domain	CATH (4.3.0)
A	2.40.10.10	Mainly Beta	Beta Barrel	Thrombin, subunit H	Trypsin-like serine proteases	CATH (4.3.0)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A, B, C, D	PF21287	Complement factor I, KAZAL domain (Kazal_CFAI)	Complement factor I, KAZAL domain	Complement factor I (CFAI) is a trypsin-like serine protease that plays an essential role in regulating the immune response by controlling all complement pathways. It cleaves three peptide bonds in the alpha-chain of C3b and two in the alpha-chain of ...	Complement factor I (CFAI) is a trypsin-like serine protease that plays an essential role in regulating the immune response by controlling all complement pathways. It cleaves three peptide bonds in the alpha-chain of C3b and two in the alpha-chain of C4b which inactivate these proteins. It consists of an N-terminal FI and membrane attack domain (FIMAC or Factor I-like modules FIM), a scavenger receptor cysteine-rich (SRCR) domain (Pfam:PF00530), LDLRA1 and LDLRA2 (Pfam:PF00057) and a C-terminal catalytic serine protease domain (Pfam:PF00089) [1,2]. FIMs are also present in complement proteins C6 and C7, and participate in protein-protein interactions that critical to the progress of a complement-mediated immune response. In CFAI, the FIMAC domain is important for the ability of FI to degrade C4b and C3b [1-2]. It consists of a small N-terminal FOLN subdomain (Pfam:PF21286) and a larger C-terminal KAZAL domain. This entry represents the KAZAL domain of CFAI FIMAC domain.	Domain
A, B, C, D	PF21286	Complement factor I, FIMAC N-terminal domain (CFAI_FIMAC_N)	Complement factor I, FIMAC N-terminal domain	Complement factor I (CFAI) is a trypsin-like serine protease that plays an essential role in regulating the immune response by controlling all complement pathways. It cleaves three peptide bonds in the alpha-chain of C3b and two in the alpha-chain of ...	Complement factor I (CFAI) is a trypsin-like serine protease that plays an essential role in regulating the immune response by controlling all complement pathways. It cleaves three peptide bonds in the alpha-chain of C3b and two in the alpha-chain of C4b which inactivate these proteins. It consists of an N-terminal FI and membrane attack domain (FIMAC or Factor I-like modules FIM), a scavenger receptor cysteine-rich (SRCR) domain (Pfam:PF00530), LDLRA1 and LDLRA2 (Pfam:PF00057) and a C-terminal catalytic serine protease domain (Pfam:PF00089) [1,2]. FIMs are also present in complement proteins C6 and C7, and participate in protein-protein interactions that critical to the progress of a complement-mediated immune response. In CFAI, the FIMAC domain is important for the ability of FI to degrade C4b and C3b [1-2]. It consists of a a small N-terminal FOLN subdomain and a larger C-terminal KAZAL domain. This entry represents the N-terminal region of FIMAC, whose structure is a truncated form of the epidermal growth factor (EGF) domain [3].	Domain
A, B, C, D	PF00089	Trypsin (Trypsin)	Trypsin		Domain
A, B, C, D	PF00530	Scavenger receptor cysteine-rich domain (SRCR)	Scavenger receptor cysteine-rich domain	These domains are disulphide rich extracellular domains. These domains are found in several extracellular receptors and may be involved in protein-protein interactions.	Domain
A, B, C, D	PF00057	Low-density lipoprotein receptor domain class A (Ldl_recept_a)	Low-density lipoprotein receptor domain class A	-	Repeat

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A, B, C, D	HUMAN COMPLEMENT FACTOR I	peptidase activity catalytic activity, acting on a protein serine hydrolase activity serine-type peptidase activity hydrolase activity serine-type endopeptidase activity catalytic activity endopeptidase activity cation binding ion binding binding metal ion binding small molecule binding	adaptive immune response based on somatic recombination of immune receptors built from immunoglobulin superfamily domains lymphocyte mediated immunity humoral immune response response to stimulus positive regulation of biological process positive regulation of response to stimulus complement activation humoral immune response mediated by circulating immunoglobulin positive regulation of immune response leukocyte mediated immunity regulation of immune system process positive regulation of immune system process complement activation, classical pathway regulation of biological process adaptive immune response based on somatic recombination of immune receptors built from immunoglobulin superfamily domains lymphocyte mediated immunity humoral immune response response to stimulus positive regulation of biological process positive regulation of response to stimulus complement activation humoral immune response mediated by circulating immunoglobulin positive regulation of immune response leukocyte mediated immunity regulation of immune system process positive regulation of immune system process complement activation, classical pathway regulation of biological process immune response biological regulation immunoglobulin mediated immune response adaptive immune response immune effector process regulation of response to stimulus immune system process B cell mediated immunity regulation of immune response activation of immune response biological process involved in interspecies interaction between organisms response to other organism defense response defense response to symbiont response to external stimulus response to biotic stimulus defense response to other organism response to stress innate immune response response to external biotic stimulus proteolysis metabolic process cellular process primary metabolic process protein metabolic process macromolecule metabolic process	cellular anatomical structure membrane extracellular exosome membrane-bounded organelle extracellular vesicle extracellular organelle extracellular region organelle extracellular space vesicle extracellular membrane-bounded organelle

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A, B, C, D	IPR002172	Low-density lipoprotein (LDL) receptor class A repeat	Repeat
A, B, C, D	IPR036058	Kazal domain superfamily	Homologous Superfamily
A, B, C, D	IPR048722	Complement factor I, FIMAC N-terminal domain	Domain
A, B, C, D	IPR036055	LDL receptor-like superfamily	Homologous Superfamily
A, B, C, D	IPR002350	Kazal domain	Domain
A, B, C, D	IPR018114	Serine proteases, trypsin family, histidine active site	Active Site
A, B, C, D	IPR003884	Factor I / membrane attack complex	Domain
A, B, C, D	IPR043504	Peptidase_S1_PA_chymotrypsin	Unknown
A, B, C, D	IPR048719	Complement factor I, KAZAL domain	Domain
A, B, C, D	IPR009003	Peptidase S1, PA clan	Homologous Superfamily
A, B, C, D	IPR001190	SRCR domain	Domain
A, B, C, D	IPR001314	Peptidase S1A, chymotrypsin family	Family
A, B, C, D	IPR033116	Serine proteases, trypsin family, serine active site	Active Site
A, B, C, D	IPR036772	SRCR-like domain superfamily	Homologous Superfamily
A, B, C, D	IPR001254	Serine proteases, trypsin domain	Domain
A, B, C, D	IPR023415	Low-density lipoprotein (LDL) receptor class A, conserved site	Conserved Site

Pharos: Disease Associations Pharos Homepage Annotation

Chains	Drug Target	Associated Disease
A, B, C, D	Pharos: P05156	complement factor I deficiency age-related macular degeneration age related macular degeneration 13 atypical hemolytic-uremic syndrome Doyne honeycomb retinal dystrophy hemolytic-uremic syndrome atypical hemolytic-uremic syndrome with I factor anomaly lung cancer malignant ependymoma medulloblastoma ovarian cancer adenoma pilocytic astrocytoma astrocytic tumor subependymal giant cell astrocytoma complement factor I deficiency age-related macular degeneration age related macular degeneration 13 atypical hemolytic-uremic syndrome Doyne honeycomb retinal dystrophy hemolytic-uremic syndrome atypical hemolytic-uremic syndrome with I factor anomaly lung cancer malignant ependymoma medulloblastoma ovarian cancer adenoma pilocytic astrocytoma astrocytic tumor subependymal giant cell astrocytoma Barrett esophagus wet macular degeneration congenital afibrinogenemia HELLP syndrome lung carcinoma malignant glioma nephrosclerosis pancreatic ductal adenocarcinoma pituitary cancer transitional cell carcinoma breast cancer Crohn disease Drusen, Radial, Autosomal Dominant hemolytic anemia interstitial cystitis macular degeneration malignant mesothelioma non-small cell lung carcinoma periodontitis retinal degeneration ulcerative colitis cystic fibrosis glioblastoma

RCSB PDB Core Operations are funded by the U.S. National Science Foundation (DBI-2321666), the US Department of Energy (DE-SC0019749), and the National Cancer Institute, National Institute of Allergy and Infectious Diseases, and National Institute of General Medical Sciences of the National Institutes of Health under grant R01GM157729. RCSB PDB uses resources of the National Energy Research Scientific Computing Center (NERSC), a Department of Energy User Facility.