1PK6

Globular Head of the Complement System Protein C1q

External Resource: Annotation

Domain Annotation: SCOP/SCOPe Classification
Domain Annotation: SCOP2 Classification
Domain Annotation: ECOD Classification
Domain Annotation: CATH
Protein Family Annotation
Gene Ontology: Gene Product Annotation
InterPro: Protein Family Classification
Pharos: Disease Associations

Domain Annotation: SCOP/SCOPe Classification SCOP-e Database Homepage

Chains	Domain Info	Class	Fold	Superfamily	Family	Domain	Species	Provenance Source (Version)
A	d1pk6a_	All beta proteins	TNF-like	TNF-like	TNF-like	Complement c1q globular head, A chain	(Homo sapiens ) [TaxId: 9606 ],	SCOPe (2.08)
B	d1pk6b_	All beta proteins	TNF-like	TNF-like	TNF-like	Complement c1q globular head, B chain	(Homo sapiens ) [TaxId: 9606 ],	SCOPe (2.08)
C	d1pk6c_	All beta proteins	TNF-like	TNF-like	TNF-like	Complement c1q globular head, C chain	(Homo sapiens ) [TaxId: 9606 ],	SCOPe (2.08)

Domain Annotation: SCOP2 Classification SCOP2 Database Homepage

Chains	Type	Family Name	Domain Identifier	Family Identifier	Provenance Source (Version)
A	SCOP2 Family	TNF-like	8026449	4000294	SCOP2 (2022-06-29)
A	SCOP2 Superfamily	TNF-like	8038828	3000061	SCOP2 (2022-06-29)
B	SCOP2 Family	TNF-like	8026453	4000294	SCOP2 (2022-06-29)
B	SCOP2 Superfamily	TNF-like	8038832	3000061	SCOP2 (2022-06-29)
C	SCOP2 Family	TNF-like	8026455	4000294	SCOP2 (2022-06-29)
C	SCOP2 Superfamily	TNF-like	8038834	3000061	SCOP2 (2022-06-29)

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
A	PF00386	e1pk6A1	A: beta sandwiches	X: jelly-roll	H: TNF-like (From Topology)	T: TNF-like	F: PF00386	ECOD (1.6)
B	PF00386	e1pk6B1	A: beta sandwiches	X: jelly-roll	H: TNF-like (From Topology)	T: TNF-like	F: PF00386	ECOD (1.6)
C	PF00386	e1pk6C1	A: beta sandwiches	X: jelly-roll	H: TNF-like (From Topology)	T: TNF-like	F: PF00386	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A	2.60.120.40	Mainly Beta	Sandwich	Jelly Rolls		CATH (4.3.0)
B	2.60.120.40	Mainly Beta	Sandwich	Jelly Rolls		CATH (4.3.0)
C	2.60.120.40	Mainly Beta	Sandwich	Jelly Rolls		CATH (4.3.0)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A	PF01391	Collagen triple helix repeat (20 copies) (Collagen)	Collagen triple helix repeat (20 copies)	-	Repeat
A	PF00386	C1q domain (C1q)	C1q domain	C1q is a subunit of the C1 enzyme complex that activates the serum complement system.	Domain
B	PF01391	Collagen triple helix repeat (20 copies) (Collagen)	Collagen triple helix repeat (20 copies)	-	Repeat
B	PF00386	C1q domain (C1q)	C1q domain	C1q is a subunit of the C1 enzyme complex that activates the serum complement system.	Domain
C	PF01391	Collagen triple helix repeat (20 copies) (Collagen)	Collagen triple helix repeat (20 copies)	-	Repeat
C	PF00386	C1q domain (C1q)	C1q domain	C1q is a subunit of the C1 enzyme complex that activates the serum complement system.	Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A	Complement C1q subcomponent, A chain precursor	amide binding amyloid-beta binding binding peptide binding	developmental process multicellular organismal process visual system development pattern specification process nervous system development regionalization multicellular organism development central nervous system development anatomical structure development sensory system development vertebrate eye-specific patterning system development cellular developmental process response to stimulus developmental process multicellular organismal process visual system development pattern specification process nervous system development regionalization multicellular organism development central nervous system development anatomical structure development sensory system development vertebrate eye-specific patterning system development cellular developmental process response to stimulus astrocyte differentiation cell development astrocyte activation glial cell development neurogenesis astrocyte development gliogenesis cell differentiation response to stress defense response cell activation glial cell differentiation cellular process glial cell activation inflammatory response neuroinflammatory response adaptive immune response based on somatic recombination of immune receptors built from immunoglobulin superfamily domains lymphocyte mediated immunity humoral immune response 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 developmental maturation generation of neurons neuron differentiation neuron remodeling anatomical structure maturation neuron development neuron maturation cell maturation cellular component organization cellular component disassembly complement-mediated synapse pruning cell junction organization cell junction disassembly synapse pruning synapse organization cellular component organization or biogenesis biological process involved in interspecies interaction between organisms response to other organism defense response to symbiont response to external stimulus response to biotic stimulus defense response to other organism innate immune response response to external biotic stimulus signaling cell-cell signaling cell communication myeloid leukocyte activation leukocyte activation macrophage activation leukocyte activation involved in inflammatory response microglial cell activation	protein-containing complex collagen trimer complement component C1 complex extracellular region cellular anatomical entity cell periphery extracellular matrix external encapsulating structure collagen-containing extracellular matrix complement component C1q complex synapse cell junction postsynapse
B	Complement C1q subcomponent, B chain precursor	-	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 cellular component organization cellular component disassembly cell junction organization cell junction disassembly synapse pruning cellular process synapse organization cellular component organization or biogenesis	protein-containing complex collagen trimer complement component C1 complex extracellular region cellular anatomical entity extracellular space blood microparticle cell periphery extracellular matrix external encapsulating structure collagen-containing extracellular matrix complement component C1q complex synapse cell junction protein-containing complex collagen trimer complement component C1 complex extracellular region cellular anatomical entity extracellular space blood microparticle cell periphery extracellular matrix external encapsulating structure collagen-containing extracellular matrix complement component C1q complex synapse cell junction postsynapse
C	Complement C1q subcomponent, C chain precursor	-	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 regulation of leukocyte differentiation multicellular organismal process myeloid leukocyte differentiation regulation of cellular process cellular developmental process regulation of developmental process negative regulation of biological process cell development regulation of cell differentiation mononuclear cell differentiation regulation of cell development multicellular organism development cell differentiation anatomical structure development negative regulation of cellular process regulation of multicellular organismal process negative regulation of cell differentiation negative regulation of macrophage differentiation regulation of macrophage differentiation negative regulation of hemopoiesis developmental process regulation of multicellular organismal development negative regulation of leukocyte differentiation hemopoiesis regulation of myeloid cell differentiation negative regulation of developmental process macrophage differentiation regulation of myeloid leukocyte differentiation negative regulation of myeloid cell differentiation negative regulation of myeloid leukocyte differentiation negative regulation of cell development myeloid cell differentiation negative regulation of immune system process regulation of hemopoiesis cellular process negative regulation of multicellular organismal process leukocyte differentiation 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 regulation of granulocyte differentiation negative regulation of granulocyte differentiation granulocyte differentiation cellular component organization cellular component disassembly cell junction organization cell junction disassembly synapse pruning synapse organization cellular component organization or biogenesis	protein-containing complex collagen trimer complement component C1 complex extracellular region cellular anatomical entity extracellular space blood microparticle cell periphery extracellular matrix external encapsulating structure collagen-containing extracellular matrix complement component C1q complex synapse cell junction protein-containing complex collagen trimer complement component C1 complex extracellular region cellular anatomical entity extracellular space blood microparticle cell periphery extracellular matrix external encapsulating structure collagen-containing extracellular matrix complement component C1q complex synapse cell junction postsynapse

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A	IPR008160	Collagen triple helix repeat	Repeat
A	IPR008983	Tumour necrosis factor-like domain superfamily	Homologous Superfamily
A	IPR001073	C1q domain	Domain
B	IPR008160	Collagen triple helix repeat	Repeat
B	IPR008983	Tumour necrosis factor-like domain superfamily	Homologous Superfamily
B	IPR001073	C1q domain	Domain
C	IPR008160	Collagen triple helix repeat	Repeat
C	IPR008983	Tumour necrosis factor-like domain superfamily	Homologous Superfamily
C	IPR001073	C1q domain	Domain

Pharos: Disease Associations Pharos Homepage Annotation

Chains	Drug Target	Associated Disease
A	Pharos: P02745	C1Q deficiency IgA glomerulonephritis membranoproliferative glomerulonephritis type III hypersensitivity disease Down syndrome systemic lupus erythematosus Liver Cirrhosis, Experimental lung adenocarcinoma adrenal cortex carcinoma myopathy Becker muscular dystrophy pancreatic intraductal papillary-mucinous carcinoma Creutzfeldt Jacob disease pilocytic astrocytoma subependymal giant cell astrocytoma C1Q deficiency IgA glomerulonephritis membranoproliferative glomerulonephritis type III hypersensitivity disease Down syndrome systemic lupus erythematosus Liver Cirrhosis, Experimental lung adenocarcinoma adrenal cortex carcinoma myopathy Becker muscular dystrophy pancreatic intraductal papillary-mucinous carcinoma Creutzfeldt Jacob disease pilocytic astrocytoma subependymal giant cell astrocytoma exanthem head and neck cancer invasive ductal breast carcinoma limb-girdle muscular dystrophy lung cancer malignant glioma astrocytic tumor non-small cell lung carcinoma pancreatic intraductal papillary-mucinous neoplasm cutaneous lupus erythematosus primary membranoproliferative glomerulonephritis Duchenne muscular dystrophy ulcerative colitis juvenile dermatomyositis lung carcinoma medulloblastoma autosomal systemic lupus erythematosus type 16 ovarian cancer chronic obstructive pulmonary disease pancreatic intraductal papillary-mucinous neoplasm with low grade dysplasia dense deposit disease schizophrenia esophageal adenocarcinoma tuberculosis glioblastoma interstitial cystitis
B	Pharos: P02746	C1Q deficiency IgA glomerulonephritis Liver Cirrhosis, Experimental primary immunodeficiency disease cirrhosis of liver Down syndrome juvenile dermatomyositis lung carcinoma myocardial ischemia non-small cell lung carcinoma adrenal cortex carcinoma Sjogren syndrome Creutzfeldt Jacob disease ulcerative colitis glioblastoma C1Q deficiency IgA glomerulonephritis Liver Cirrhosis, Experimental primary immunodeficiency disease cirrhosis of liver Down syndrome juvenile dermatomyositis lung carcinoma myocardial ischemia non-small cell lung carcinoma adrenal cortex carcinoma Sjogren syndrome Creutzfeldt Jacob disease ulcerative colitis glioblastoma interstitial cystitis large cell medulloblastoma lung adenocarcinoma myopathy ovarian cancer pancreatic intraductal papillary-mucinous neoplasm with low grade dysplasia chronic kidney disease psoriasis coronary artery disease subependymal giant cell astrocytoma cutaneous lupus erythematosus esophageal adenocarcinoma head and neck cancer invasive ductal breast carcinoma limb-girdle muscular dystrophy lung cancer medulloblastoma nasopharyngeal carcinoma ovarian cyst astrocytic tumor pilocytic astrocytoma chronic obstructive pulmonary disease schizophrenia corpus luteum cyst tuberculosis dermatomyositis
C	Pharos: P02747	C1Q deficiency Liver Cirrhosis, Experimental myopathy pancreatic ductal adenocarcinoma tuberculosis adrenal cortex carcinoma breast cancer Creutzfeldt Jacob disease Emery-Dreifuss muscular dystrophy interstitial cystitis large cell medulloblastoma lung carcinoma non-small cell lung carcinoma pilocytic astrocytoma ulcerative colitis C1Q deficiency Liver Cirrhosis, Experimental myopathy pancreatic ductal adenocarcinoma tuberculosis adrenal cortex carcinoma breast cancer Creutzfeldt Jacob disease Emery-Dreifuss muscular dystrophy interstitial cystitis large cell medulloblastoma lung carcinoma non-small cell lung carcinoma pilocytic astrocytoma ulcerative colitis astrocytic tumor Down syndrome glioblastoma invasive ductal breast carcinoma limb-girdle muscular dystrophy malignant glioma ovarian cancer subependymal giant cell astrocytoma Becker muscular dystrophy chronic obstructive pulmonary disease Duchenne muscular dystrophy head and neck cancer juvenile dermatomyositis

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 R01GM133198.