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P02747 (C1QC_HUMAN) Reviewed, UniProtKB/Swiss-Prot

Last modified July 9, 2014. Version 155. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (6) | Third-party data text xml rdf/xml gff fasta
to top of pageNames·Attributes·General annotation·Ontologies·Sequence annotation·Sequences·References·Web links·Cross-refs·Entry info·DocumentsCustomize order

Names and origin

Protein namesRecommended name:
Complement C1q subcomponent subunit C
Gene names
Name:C1QC
Synonyms:C1QG
OrganismHomo sapiens (Human) [Reference proteome]
Taxonomic identifier9606 [NCBI]
Taxonomic lineageEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo

Protein attributes

Sequence length245 AA.
Sequence statusComplete.
Sequence processingThe displayed sequence is further processed into a mature form.
Protein existenceEvidence at protein level

General annotation (Comments)

Function

C1q associates with the proenzymes C1r and C1s to yield C1, the first component of the serum complement system. The collagen-like regions of C1q interact with the Ca2+-dependent C1r2C1s2 proenzyme complex, and efficient activation of C1 takes place on interaction of the globular heads of C1q with the Fc regions of IgG or IgM antibody present in immune complexes.

Subunit structure

C1 is a calcium-dependent trimolecular complex of C1q, R and S in the molar ration of 1:2:2. C1q subcomponent is composed of nine subunits, six of which are disulfide-linked dimers of the A and B chains, and three of which are disulfide-linked dimers of the C chain.

Subcellular location

Secreted.

Post-translational modification

O-linked glycans consist of Glc-Gal disaccharides bound to the oxygen atom of post-translationally added hydroxyl groups.

Involvement in disease

Complement component C1q deficiency (C1QD) [MIM:613652]: A disorder caused by impaired activation of the complement classical pathway. It generally leads to severe immune complex disease with features of systemic lupus erythematosus and glomerulonephritis.
Note: The disease is caused by mutations affecting the gene represented in this entry. Ref.9

Sequence similarities

Contains 1 C1q domain.

Contains 1 collagen-like domain.

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Signal peptide1 – 2828 Ref.6
Chain29 – 245217Complement C1q subcomponent subunit C
PRO_0000003524

Regions

Domain31 – 11282Collagen-like
Domain115 – 245131C1q

Amino acid modifications

Modified residue3614-hydroxyproline
Modified residue3914-hydroxyproline
Modified residue4214-hydroxyproline
Modified residue4514-hydroxyproline
Modified residue5414-hydroxyproline
Modified residue5715-hydroxylysine
Modified residue6314-hydroxyproline
Modified residue7515-hydroxylysine
Modified residue8114-hydroxyproline
Modified residue9314-hydroxyproline
Modified residue9614-hydroxyproline
Modified residue9914-hydroxyproline
Modified residue10514-hydroxyproline
Glycosylation751O-linked (Gal...)
Disulfide bond32Interchain

Natural variations

Natural variant341G → R in C1QD. Ref.9
VAR_008542

Experimental info

Sequence conflict141K → R in BAB71575. Ref.3
Sequence conflict231P → A no nucleotide entry Ref.1
Sequence conflict26 – 272GQ → AK in AAP97191. Ref.2
Sequence conflict571K → P AA sequence Ref.6
Sequence conflict661P → K AA sequence Ref.6
Sequence conflict721K → P AA sequence Ref.6
Sequence conflict841P → K AA sequence Ref.6
Sequence conflict871N → D AA sequence Ref.6
Sequence conflict901M → N AA sequence Ref.6
Sequence conflict1041I → F in AAP97191. Ref.2
Sequence conflict1491G → E in AAP97191. Ref.2
Sequence conflict2151E → G in BAB71575. Ref.3

Secondary structure

......................... 245
Helix Strand Turn

Details...

Sequences

Sequence LengthMass (Da)Tools
P02747 [UniParc].

Last modified April 16, 2002. Version 3.
Checksum: FA17117EB7ABFC12

FASTA24525,774
        10         20         30         40         50         60 
MDVGPSSLPH LGLKLLLLLL LLPLRGQANT GCYGIPGMPG LPGAPGKDGY DGLPGPKGEP 

        70         80         90        100        110        120 
GIPAIPGIRG PKGQKGEPGL PGHPGKNGPM GPPGMPGVPG PMGIPGEPGE EGRYKQKFQS 

       130        140        150        160        170        180 
VFTVTRQTHQ PPAPNSLIRF NAVLTNPQGD YDTSTGKFTC KVPGLYYFVY HASHTANLCV 

       190        200        210        220        230        240 
LLYRSGVKVV TFCGHTSKTN QVNSGGVLLR LQVGEEVWLA VNDYYDMVGI QGSDSVFSGF 


LLFPD 

« Hide

References

« Hide 'large scale' references
[1]"Characterization and organization of the genes encoding the A-, B- and C-chains of human complement subcomponent C1q. The complete derived amino acid sequence of human C1q."
Sellar G.C., Blake D.J., Reid K.B.M.
Biochem. J. 274:481-490(1991) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
Tissue: Monocyte.
[2]"Cloning and characterization of a novel human cDNA homology to murine C1q C-chain mRNA."
Dai F.Y., Yu L., Wan Y.Z., Zhang H.L., Huang J., Zhao S.Y.
Submitted (JUL-2003) to the EMBL/GenBank/DDBJ databases
Cited for: NUCLEOTIDE SEQUENCE [MRNA].
[3]"Complete sequencing and characterization of 21,243 full-length human cDNAs."
Ota T., Suzuki Y., Nishikawa T., Otsuki T., Sugiyama T., Irie R., Wakamatsu A., Hayashi K., Sato H., Nagai K., Kimura K., Makita H., Sekine M., Obayashi M., Nishi T., Shibahara T., Tanaka T., Ishii S. expand/collapse author list , Yamamoto J., Saito K., Kawai Y., Isono Y., Nakamura Y., Nagahari K., Murakami K., Yasuda T., Iwayanagi T., Wagatsuma M., Shiratori A., Sudo H., Hosoiri T., Kaku Y., Kodaira H., Kondo H., Sugawara M., Takahashi M., Kanda K., Yokoi T., Furuya T., Kikkawa E., Omura Y., Abe K., Kamihara K., Katsuta N., Sato K., Tanikawa M., Yamazaki M., Ninomiya K., Ishibashi T., Yamashita H., Murakawa K., Fujimori K., Tanai H., Kimata M., Watanabe M., Hiraoka S., Chiba Y., Ishida S., Ono Y., Takiguchi S., Watanabe S., Yosida M., Hotuta T., Kusano J., Kanehori K., Takahashi-Fujii A., Hara H., Tanase T.-O., Nomura Y., Togiya S., Komai F., Hara R., Takeuchi K., Arita M., Imose N., Musashino K., Yuuki H., Oshima A., Sasaki N., Aotsuka S., Yoshikawa Y., Matsunawa H., Ichihara T., Shiohata N., Sano S., Moriya S., Momiyama H., Satoh N., Takami S., Terashima Y., Suzuki O., Nakagawa S., Senoh A., Mizoguchi H., Goto Y., Shimizu F., Wakebe H., Hishigaki H., Watanabe T., Sugiyama A., Takemoto M., Kawakami B., Yamazaki M., Watanabe K., Kumagai A., Itakura S., Fukuzumi Y., Fujimori Y., Komiyama M., Tashiro H., Tanigami A., Fujiwara T., Ono T., Yamada K., Fujii Y., Ozaki K., Hirao M., Ohmori Y., Kawabata A., Hikiji T., Kobatake N., Inagaki H., Ikema Y., Okamoto S., Okitani R., Kawakami T., Noguchi S., Itoh T., Shigeta K., Senba T., Matsumura K., Nakajima Y., Mizuno T., Morinaga M., Sasaki M., Togashi T., Oyama M., Hata H., Watanabe M., Komatsu T., Mizushima-Sugano J., Satoh T., Shirai Y., Takahashi Y., Nakagawa K., Okumura K., Nagase T., Nomura N., Kikuchi H., Masuho Y., Yamashita R., Nakai K., Yada T., Nakamura Y., Ohara O., Isogai T., Sugano S.
Nat. Genet. 36:40-45(2004) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
Tissue: Cerebellum.
[4]"The DNA sequence and biological annotation of human chromosome 1."
Gregory S.G., Barlow K.F., McLay K.E., Kaul R., Swarbreck D., Dunham A., Scott C.E., Howe K.L., Woodfine K., Spencer C.C.A., Jones M.C., Gillson C., Searle S., Zhou Y., Kokocinski F., McDonald L., Evans R., Phillips K. expand/collapse author list , Atkinson A., Cooper R., Jones C., Hall R.E., Andrews T.D., Lloyd C., Ainscough R., Almeida J.P., Ambrose K.D., Anderson F., Andrew R.W., Ashwell R.I.S., Aubin K., Babbage A.K., Bagguley C.L., Bailey J., Beasley H., Bethel G., Bird C.P., Bray-Allen S., Brown J.Y., Brown A.J., Buckley D., Burton J., Bye J., Carder C., Chapman J.C., Clark S.Y., Clarke G., Clee C., Cobley V., Collier R.E., Corby N., Coville G.J., Davies J., Deadman R., Dunn M., Earthrowl M., Ellington A.G., Errington H., Frankish A., Frankland J., French L., Garner P., Garnett J., Gay L., Ghori M.R.J., Gibson R., Gilby L.M., Gillett W., Glithero R.J., Grafham D.V., Griffiths C., Griffiths-Jones S., Grocock R., Hammond S., Harrison E.S.I., Hart E., Haugen E., Heath P.D., Holmes S., Holt K., Howden P.J., Hunt A.R., Hunt S.E., Hunter G., Isherwood J., James R., Johnson C., Johnson D., Joy A., Kay M., Kershaw J.K., Kibukawa M., Kimberley A.M., King A., Knights A.J., Lad H., Laird G., Lawlor S., Leongamornlert D.A., Lloyd D.M., Loveland J., Lovell J., Lush M.J., Lyne R., Martin S., Mashreghi-Mohammadi M., Matthews L., Matthews N.S.W., McLaren S., Milne S., Mistry S., Moore M.J.F., Nickerson T., O'Dell C.N., Oliver K., Palmeiri A., Palmer S.A., Parker A., Patel D., Pearce A.V., Peck A.I., Pelan S., Phelps K., Phillimore B.J., Plumb R., Rajan J., Raymond C., Rouse G., Saenphimmachak C., Sehra H.K., Sheridan E., Shownkeen R., Sims S., Skuce C.D., Smith M., Steward C., Subramanian S., Sycamore N., Tracey A., Tromans A., Van Helmond Z., Wall M., Wallis J.M., White S., Whitehead S.L., Wilkinson J.E., Willey D.L., Williams H., Wilming L., Wray P.W., Wu Z., Coulson A., Vaudin M., Sulston J.E., Durbin R.M., Hubbard T., Wooster R., Dunham I., Carter N.P., McVean G., Ross M.T., Harrow J., Olson M.V., Beck S., Rogers J., Bentley D.R.
Nature 441:315-321(2006) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
[5]"The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)."
The MGC Project Team
Genome Res. 14:2121-2127(2004) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
Tissue: Brain.
[6]"Complete amino acid sequences of the three collagen-like regions present in subcomponent C1q of the first component of human complement."
Reid K.B.M.
Biochem. J. 179:367-371(1979) [PubMed] [Europe PMC] [Abstract]
Cited for: PROTEIN SEQUENCE OF 29-122.
[7]"The crystal structure of the globular head of complement protein C1q provides a basis for its versatile recognition properties."
Gaboriaud C., Juanhuix J., Gruez A., Lacroix M., Darnault C., Pignol D., Verger D., Fontecilla-Camps J.-C., Arlaud G.J.
J. Biol. Chem. 278:46974-46982(2003) [PubMed] [Europe PMC] [Abstract]
Cited for: X-RAY CRYSTALLOGRAPHY (1.85 ANGSTROMS) OF 117-245.
[8]"Molecular basis of hereditary C1q deficiency."
Petry F.
Immunobiology 199:286-294(1998) [PubMed] [Europe PMC] [Abstract]
Cited for: REVIEW ON C1Q DEFICIENCY.
[9]"Homozygous hereditary C1q deficiency and systemic lupus erythematosus. A new family and the molecular basis of C1q deficiency in three families."
Slingsby J.H., Norsworthy P., Pearce G., Vaishnaw A.K., Issler H., Morley B.J., Walport M.J.
Arthritis Rheum. 39:663-670(1996) [PubMed] [Europe PMC] [Abstract]
Cited for: VARIANT C1QD ARG-34.
+Additional computationally mapped references.

Web resources

C1QGbase

C1QC mutation db

Cross-references

Sequence databases

EMBL
GenBank
DDBJ
AF087892 mRNA. Translation: AAP97191.1.
AK057792 mRNA. Translation: BAB71575.1.
AL158086 Genomic DNA. Translation: CAI22894.1.
BC009016 mRNA. Translation: AAH09016.1.
CCDSCCDS227.1.
PIRC1HUQC. S14351.
RefSeqNP_001107573.1. NM_001114101.1.
NP_758957.2. NM_172369.3.
UniGeneHs.467753.

3D structure databases

PDBe
RCSB-PDB
PDBj
EntryMethodResolution (Å)ChainPositionsPDBsum
1PK6X-ray1.85C117-245[»]
2JG8X-ray2.05C/F115-245[»]
2JG9X-ray1.90C/F115-245[»]
2WNUX-ray2.30C/F115-245[»]
2WNVX-ray1.25C/F115-245[»]
ProteinModelPortalP02747.
SMRP02747. Positions 34-113, 117-245.
ModBaseSearch...
MobiDBSearch...

Protein-protein interaction databases

BioGrid107175. 2 interactions.
IntActP02747. 2 interactions.
MINTMINT-6630018.
STRING9606.ENSP00000363768.

Chemistry

DrugBankDB00054. Abciximab.
DB00051. Adalimumab.
DB00092. Alefacept.
DB00087. Alemtuzumab.
DB00074. Basiliximab.
DB00112. Bevacizumab.
DB00002. Cetuximab.
DB00111. Daclizumab.
DB00095. Efalizumab.
DB00005. Etanercept.
DB00056. Gemtuzumab ozogamicin.
DB00078. Ibritumomab.
DB00028. Immune globulin.
DB00075. Muromonab.
DB00108. Natalizumab.
DB00110. Palivizumab.
DB00073. Rituximab.
DB00081. Tositumomab.
DB00072. Trastuzumab.

Polymorphism databases

DMDM20178281.

Proteomic databases

PaxDbP02747.
PeptideAtlasP02747.
PRIDEP02747.

Protocols and materials databases

DNASU714.
StructuralBiologyKnowledgebaseSearch...

Genome annotation databases

EnsemblENST00000374637; ENSP00000363768; ENSG00000159189.
ENST00000374639; ENSP00000363770; ENSG00000159189.
ENST00000374640; ENSP00000363771; ENSG00000159189.
GeneID714.
KEGGhsa:714.
UCSCuc001bga.4. human.

Organism-specific databases

CTD714.
GeneCardsGC01P022970.
HGNCHGNC:1245. C1QC.
HPACAB009828.
HPA001471.
MIM120575. gene.
613652. phenotype.
neXtProtNX_P02747.
Orphanet169147. Immunodeficiency due to an early component of complement deficiency.
PharmGKBPA25626.
GenAtlasSearch...

Phylogenomic databases

eggNOGNOG115796.
HOGENOMHOG000085653.
HOVERGENHBG108220.
InParanoidP02747.
KOK03988.
OMAQTANLCV.
OrthoDBEOG70ZZPW.
PhylomeDBP02747.
TreeFamTF329591.

Enzyme and pathway databases

ReactomeREACT_6900. Immune System.

Gene expression databases

BgeeP02747.
CleanExHS_C1QC.
GenevestigatorP02747.

Family and domain databases

Gene3D2.60.120.40. 1 hit.
InterProIPR001073. C1q.
IPR008160. Collagen.
IPR008983. Tumour_necrosis_fac-like_dom.
[Graphical view]
PfamPF00386. C1q. 1 hit.
PF01391. Collagen. 2 hits.
[Graphical view]
PRINTSPR00007. COMPLEMNTC1Q.
SMARTSM00110. C1Q. 1 hit.
[Graphical view]
SUPFAMSSF49842. SSF49842. 1 hit.
PROSITEPS50871. C1Q. 1 hit.
[Graphical view]
ProtoNetSearch...

Other

ChiTaRSC1QC. human.
EvolutionaryTraceP02747.
GenomeRNAi714.
NextBio2902.
PMAP-CutDBP02747.
PROP02747.
SOURCESearch...

Entry information

Entry nameC1QC_HUMAN
AccessionPrimary (citable) accession number: P02747
Secondary accession number(s): Q7Z502, Q96DL2, Q96H05
Entry history
Integrated into UniProtKB/Swiss-Prot: July 21, 1986
Last sequence update: April 16, 2002
Last modified: July 9, 2014
This is version 155 of the entry and version 3 of the sequence. [Complete history]
Entry statusReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program
DisclaimerAny medical or genetic information present in this entry is provided for research, educational and informational purposes only. It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care.

Relevant documents

SIMILARITY comments

Index of protein domains and families

PDB cross-references

Index of Protein Data Bank (PDB) cross-references

MIM cross-references

Online Mendelian Inheritance in Man (MIM) cross-references in UniProtKB/Swiss-Prot

Human polymorphisms and disease mutations

Index of human polymorphisms and disease mutations

Human entries with polymorphisms or disease mutations

List of human entries with polymorphisms or disease mutations

Human chromosome 1

Human chromosome 1: entries, gene names and cross-references to MIM