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Aliases for C2 Gene

Aliases for C2 Gene

  • Complement Component 2 2 3
  • C3/C5 Convertase 3 4
  • EC 4 63
  • ARMD14 3 6
  • Complement Component C2 3
  • Complement C2 3
  • EC 3.4.21 63
  • CO2 3

External Ids for C2 Gene

Previous GeneCards Identifiers for C2 Gene

  • GC06P031957
  • GC06P031636
  • GC06P031999
  • GC06P032003
  • GC06P031865
  • GC06P031682

Summaries for C2 Gene

Entrez Gene Summary for C2 Gene

  • Component C2 is a serum glycoprotein that functions as part of the classical pathway of the complement system. Activated C1 cleaves C2 into C2a and C2b. The serine proteinase C2a then combines with complement factor 4b to create the C3 or C5 convertase. Deficiency of C2 has been reported to associated with certain autoimmune diseases and SNPs in this gene have been associated with altered susceptibility to age-related macular degeneration. This gene localizes within the class III region of the MHC on the short arm of chromosome 6. Alternative splicing results in multiple transcript variants encoding distinct isoforms. Additional transcript variants have been described in publications but their full-length sequence has not been determined.[provided by RefSeq, Mar 2009]

GeneCards Summary for C2 Gene

C2 (Complement Component 2) is a Protein Coding gene. Diseases associated with C2 include c2 deficiency and macular degeneration, age-related, 14, reduced risk of. Among its related pathways are Complement and coagulation cascades and Complement and coagulation cascades. GO annotations related to this gene include serine-type endopeptidase activity. An important paralog of this gene is ENSG00000244255.

UniProtKB/Swiss-Prot for C2 Gene

  • Component C2 which is part of the classical pathway of the complement system is cleaved by activated factor C1 into two fragments: C2b and C2a. C2a, a serine protease, then combines with complement factor C4b to generate the C3 or C5 convertase

Gene Wiki entry for C2 Gene

No data available for Tocris Summary , PharmGKB "VIP" Summary , fRNAdb sequence ontologies and piRNA Summary for C2 Gene

Genomics for C2 Gene

Regulatory Elements for C2 Gene

Epigenetics Products

  • DNA Methylation CpG Assay Predesigned for Pyrosequencing in human,mouse,rat

Genomic Location for C2 Gene

31,897,785 bp from pter
31,945,674 bp from pter
47,890 bases
Plus strand

Genomic View for C2 Gene

UCSC Golden Path with GeneCards custom track
Cytogenetic band:
Genomic Location for C2 Gene
GeneLoc Logo Genomic Neighborhood Exon StructureGene Density

Proteins for C2 Gene

  • Protein details for C2 Gene (UniProtKB/Swiss-Prot)

    Protein Symbol:
    Recommended name:
    Complement C2
    Protein Accession:
    Secondary Accessions:
    • B4DPF3
    • B4DV20
    • E9PFN7
    • O19694
    • Q13904

    Protein attributes for C2 Gene

    752 amino acids
    Molecular mass:
    83268 Da
    Quaternary structure:
    • C2a interacts with Schistosoma haematobium TOR (via N-terminal extracellular domain). This results in inhibition of the classical and lectin pathway of complement activation, probably due to interference with binding of C2a to C4b such that C3 convertase cannot be formed. This infers resistance to complement-mediated cell lysis, allowing parasite survival and infection.
    • C2 is a major histocompatibility complex class-III protein

    Three dimensional structures from OCA and Proteopedia for C2 Gene

    Alternative splice isoforms for C2 Gene


neXtProt entry for C2 Gene

Proteomics data for C2 Gene at MOPED

Post-translational modifications for C2 Gene

  • Glycosylation at Asn29, Asn112, Asn290, Asn333, Asn467, Asn471, Asn621, and Asn651
  • Modification sites at PhosphoSitePlus

Antibody Products

  • R&D Systems Antibodies for C2 (Complement Component C2)
  • R&D Systems Antibodies for C2 (Complement Component C2b)

Domains for C2 Gene

Gene Families for C2 Gene


Graphical View of Domain Structure for InterPro Entry



  • P06681
  • The MIDAS-like motif in the VWFA domain binds divalent metal cations
  • Contains 1 peptidase S1 domain.
  • Contains 3 Sushi (CCP/SCR) domains.
  • Contains 1 VWFA domain.
  • Belongs to the peptidase S1 family.
genes like me logo Genes that share domains with C2: view

Function for C2 Gene

Molecular function for C2 Gene

GENATLAS Biochemistry: complement component 2,110kDa,activated by C1r to form C2a and C2b,combining with C4A and C4B to form C3/C5 convertase,classical pathway of C3 activation
UniProtKB/Swiss-Prot CatalyticActivity: Selective cleavage of Arg- -Ser bond in complement component C3 alpha-chain to form C3a and C3b, and Arg- -Xaa bond in complement component C5 alpha-chain to form C5a and C5b
UniProtKB/Swiss-Prot Function: Component C2 which is part of the classical pathway of the complement system is cleaved by activated factor C1 into two fragments: C2b and C2a. C2a, a serine protease, then combines with complement factor C4b to generate the C3 or C5 convertase

Enzyme Numbers (IUBMB) for C2 Gene

Gene Ontology (GO) - Molecular Function for C2 Gene

GO ID Qualified GO term Evidence PubMed IDs
GO:0003824 catalytic activity --
GO:0004252 serine-type endopeptidase activity IEA --
GO:0005515 protein binding --
GO:0046872 metal ion binding IEA --
genes like me logo Genes that share ontologies with C2: view

Animal Model Products

CRISPR Products

miRNA for C2 Gene

miRTarBase miRNAs that target C2

No data available for Phenotypes , Animal Models , Transcription Factor Targeting and HOMER Transcription for C2 Gene

Localization for C2 Gene

Subcellular locations from UniProtKB/Swiss-Prot for C2 Gene


Subcellular locations from

Jensen Localization Image for C2 Gene COMPARTMENTS Subcellular localization image for C2 gene
Compartment Confidence
extracellular 5
endoplasmic reticulum 1
plasma membrane 1

Gene Ontology (GO) - Cellular Components for C2 Gene

GO ID Qualified GO term Evidence PubMed IDs
GO:0005576 extracellular region TAS --
GO:0005615 extracellular space TAS 8621452
GO:0070062 extracellular exosome IDA 23533145
genes like me logo Genes that share ontologies with C2: view

Pathways for C2 Gene

genes like me logo Genes that share pathways with C2: view

Gene Ontology (GO) - Biological Process for C2 Gene

GO ID Qualified GO term Evidence PubMed IDs
GO:0006508 proteolysis IEA --
GO:0006956 complement activation TAS --
GO:0006958 complement activation, classical pathway IEA --
GO:0007584 response to nutrient IEA --
GO:0030449 regulation of complement activation TAS --
genes like me logo Genes that share ontologies with C2: view

Compounds for C2 Gene

(1) Novoseek inferred chemical compound relationships for C2 Gene

Compound -log(P) Hits PubMed IDs
serine 45.8 6
genes like me logo Genes that share compounds with C2: view

Transcripts for C2 Gene

Unigene Clusters for C2 Gene

Complement component 2:
Representative Sequences:

CRISPR Products

miRNA Products

Inhibitory RNA Products

  • Predesigned siRNA for gene silencing in human,mouse,rat for C2

Primer Products

Flow Cytometry Products

Alternative Splicing Database (ASD) splice patterns (SP) for C2 Gene

ExUns: 1a · 1b · 1c · 1d · 1e ^ 2a · 2b ^ 3 ^ 4 ^ 5 ^ 6a · 6b ^ 7 ^ 8a · 8b · 8c · 8d ^ 9 ^ 10a · 10b ^ 11 ^ 12a · 12b ^ 13 ^ 14a · 14b ·
SP1: - - - - -
SP2: - - - - - -
SP3: -
SP4: - - - - - - - - - - - -
SP5: - - - - - - - -
SP6: -
SP7: - -
SP8: - - -
SP9: - - - - -
SP12: -

ExUns: 14c ^ 15a · 15b ^ 16 ^ 17 ^ 18 ^ 19 ^ 20
SP3: -

Relevant External Links for C2 Gene

GeneLoc Exon Structure for
ECgene alternative splicing isoforms for

Expression for C2 Gene

mRNA expression in normal human tissues for C2 Gene

mRNA expression in embryonic tissues and stem cells from LifeMap Discovery

mRNA differential expression in normal tissues according to GTEx for C2 Gene

This gene is overexpressed in Liver (28.4).

Integrated Proteomics: protein expression from ProteomicsDB, PaxDb, MOPED, and MaxQB for C2 Gene

SOURCE GeneReport for Unigene cluster for C2 Gene Hs.408903

genes like me logo Genes that share expressions with C2: view

In Situ Assay Products

No data available for mRNA Expression by UniProt/SwissProt for C2 Gene

Orthologs for C2 Gene

This gene was present in the common ancestor of chordates.

Orthologs for C2 Gene

Organism Taxonomy Gene Similarity Type Details
(Pan troglodytes)
Mammalia C2 35
  • 99.65 (n)
  • 99.6 (a)
C2 36
  • 100 (a)
(Bos Taurus)
Mammalia C2 35
  • 83.73 (n)
  • 81.42 (a)
C2 36
  • 77 (a)
(Canis familiaris)
Mammalia C2 35
  • 85.29 (n)
  • 84.76 (a)
(Mus musculus)
Mammalia C2 35
  • 79.5 (n)
  • 76.6 (a)
C2 16
C2 36
  • 75 (a)
(Ornithorhynchus anatinus)
Mammalia C2 36
  • 57 (a)
(Rattus norvegicus)
Mammalia C2 35
  • 80.21 (n)
  • 78.21 (a)
(Gallus gallus)
Aves C2 35
  • 54.74 (n)
  • 44.82 (a)
C2 36
  • 40 (a)
tropical clawed frog
(Silurana tropicalis)
Amphibia c2 35
  • 49.51 (n)
  • 42.5 (a)
(Danio rerio)
Actinopterygii -- 35
C2 36
  • 31 (a)
LOC563828 35
  • 48.98 (n)
  • 39.39 (a)
sea squirt
(Ciona savignyi)
Ascidiacea -- 36
  • 20 (a)
-- 36
  • 18 (a)
-- 36
  • 19 (a)
Species with no ortholog for C2:
  • A. gosspyii yeast (Ashbya gossypii)
  • Actinobacteria (Mycobacterium tuberculosis)
  • African clawed frog (Xenopus laevis)
  • African malaria mosquito (Anopheles gambiae)
  • Alicante grape (Vitis vinifera)
  • alpha proteobacteria (Wolbachia pipientis)
  • amoeba (Dictyostelium discoideum)
  • Archea (Pyrococcus horikoshii)
  • baker's yeast (Saccharomyces cerevisiae)
  • barley (Hordeum vulgare)
  • beta proteobacteria (Neisseria meningitidis)
  • bread mold (Neurospora crassa)
  • Chromalveolata (Phytophthora infestans)
  • common water flea (Daphnia pulex)
  • corn (Zea mays)
  • E. coli (Escherichia coli)
  • filamentous fungi (Aspergillus nidulans)
  • Firmicute bacteria (Streptococcus pneumoniae)
  • fission yeast (Schizosaccharomyces pombe)
  • fruit fly (Drosophila melanogaster)
  • green algae (Chlamydomonas reinhardtii)
  • honey bee (Apis mellifera)
  • K. lactis yeast (Kluyveromyces lactis)
  • lizard (Anolis carolinensis)
  • loblloly pine (Pinus taeda)
  • malaria parasite (Plasmodium falciparum)
  • medicago trunc (Medicago Truncatula)
  • moss (Physcomitrella patens)
  • oppossum (Monodelphis domestica)
  • orangutan (Pongo pygmaeus)
  • pig (Sus scrofa)
  • rainbow trout (Oncorhynchus mykiss)
  • rice (Oryza sativa)
  • rice blast fungus (Magnaporthe grisea)
  • schistosome parasite (Schistosoma mansoni)
  • sea anemone (Nematostella vectensis)
  • sea urchin (Strongylocentrotus purpuratus)
  • sorghum (Sorghum bicolor)
  • soybean (Glycine max)
  • stem rust fungus (Puccinia graminis)
  • sugarcane (Saccharum officinarum)
  • thale cress (Arabidopsis thaliana)
  • tomato (Lycopersicon esculentum)
  • toxoplasmosis (Toxoplasma gondii)
  • Trichoplax (Trichoplax adhaerens)
  • wheat (Triticum aestivum)
  • worm (Caenorhabditis elegans)

Evolution for C2 Gene

Gene Tree for C2 (if available)
Gene Tree for C2 (if available)

Paralogs for C2 Gene

Paralogs for C2 Gene

genes like me logo Genes that share paralogs with C2: view

Variants for C2 Gene

Polymorphic Variants from UniProtKB/Swiss-Prot for C2 Gene

The variant Asp-318 is associated with a reduced risk of age-related macular degeneration (ARMD) [MIM:603075]. ARMD is a multifactorial eye disease and the most common cause of irreversible vision loss in the developed world

Sequence variations from dbSNP and Humsavar for C2 Gene

SNP ID Clin Chr 06 pos Sequence Context AA Info Type MAF
rs497309 -- 31,924,707(-) AAACT(G/T)TGGGT intron-variant
rs498240 -- 31,924,815(-) agaga(C/T)tgatg intron-variant
rs511294 -- 31,921,092(-) GGTAC(A/C)CACAC intron-variant
rs515770 -- 31,931,282(+) ttttt(A/T)attga intron-variant
rs517668 -- 31,931,520(+) accgc(C/T)cttaa intron-variant

Structural Variations from Database of Genomic Variants (DGV) for C2 Gene

Variant ID Type Subtype PubMed ID
dgv6583n71 CNV Loss 21882294
nsv884472 CNV Loss 21882294
nsv508399 CNV Loss 20534489
nsv509126 CNV Insertion 20534489
dgv6595n71 CNV Loss 21882294
nsv884476 CNV Gain 21882294
dgv6596n71 CNV Loss 21882294
dgv6597n71 CNV Loss 21882294
dgv6598n71 CNV Loss 21882294
nsv884486 CNV Loss 21882294
dgv6599n71 CNV Loss 21882294
dgv6600n71 CNV Loss 21882294
dgv6601n71 CNV Loss 21882294
nsv10822 CNV Gain 18304495
nsv884503 CNV Loss 21882294
dgv6602n71 CNV Loss 21882294
dgv6603n71 CNV Loss 21882294
nsv10823 CNV Loss 18304495
esv2658525 CNV Deletion 23128226
esv2731824 CNV Deletion 23290073
nsv823505 CNV Loss 20364138
esv2422045 CNV Deletion 20811451
dgv1928e1 CNV Complex 17122850
nsv428141 CNV Gain+Loss 18775914
dgv1929e1 CNV Complex 17122850
esv2663182 CNV Deletion 23128226
esv988690 CNV Gain 20482838
nsv830628 CNV Loss 17160897
nsv884511 CNV Loss 21882294
nsv884512 CNV Gain 21882294

Relevant External Links for C2 Gene

HapMap Linkage Disequilibrium report
Human Gene Mutation Database (HGMD)
Locus Specific Mutation Databases (LSDB)

Disorders for C2 Gene

(2) OMIM Diseases for C2 Gene (613927)


  • Complement component 2 deficiency (C2D) [MIM:217000]: A rare defect of the complement classical pathway associated with the development of autoimmune disorders, mainly systemic lupus erythematosus. Skin and joint manifestations are common and renal disease is relatively rare. Patients with complement component 2 deficiency are also reported to have recurrent invasive infections. {ECO:0000269 PubMed:8621452, ECO:0000269 PubMed:9670930}. Note=The disease is caused by mutations affecting the gene represented in this entry.

(1) University of Copenhagen DISEASES for C2 Gene

Genatlas disease for C2 Gene

Henoch-Schonlein purpura susceptibility,lupus systemic discoid syndrome,polymyositis susceptibility (C2 deficiency,type I)

Relevant External Links for C2

Genetic Association Database (GAD)
Human Genome Epidemiology (HuGE) Navigator
genes like me logo Genes that share disorders with C2: view

Publications for C2 Gene

  1. A novel type II complement C2 deficiency allele in an African- American family. (PMID: 9670930) Zhu Z.B. … Volanakis J.E. (J. Immunol. 1998) 3 4 23
  2. Structure of the human C2 gene. (PMID: 8326124) Ishii Y. … Volanakis J.E. (J. Immunol. 1993) 3 4 23
  3. Variation in factor B (BF) and complement component 2 (C2) genes is associated with age-related macular degeneration. (PMID: 16518403) Gold B. … Allikmets R. (Nat. Genet. 2006) 3 4 48
  4. Complete sequencing and characterization of 21,243 full-length human cDNAs. (PMID: 14702039) Ota T. … Sugano S. (Nat. Genet. 2004) 3 4
  5. The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC). (PMID: 15489334) Gerhard D.S. … Malek J. (Genome Res. 2004) 3 4

Products for C2 Gene

Sources for C2 Gene

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