Complement component 2

Complement component 2
PDB rendering based on 2i6q.
Available structures PDB Ortholog search: PDBe, RCSB List of PDB id codes 2I6Q​, 2I6S​, 2ODP​, 2ODQ​, 3ERB​
Identifiers
Symbols	C2 ; ARMD14; CO2
External IDs	OMIM: 613927 MGI: 88226 HomoloGene: 45 GeneCards: C2 Gene
EC number	3.4.21.43
Gene ontology Molecular function • serine-type endopeptidase activity • metal ion binding Cellular component • extracellular region • extracellular space • extracellular exosome Biological process • proteolysis • complement activation • complement activation, classical pathway • response to nutrient • regulation of complement activation • innate immune response • positive regulation of apoptotic cell clearance Sources: Amigo / QuickGO
RNA expression pattern
More reference expression data
Orthologs
Species	Human	Mouse
Entrez	717	12263
Ensembl	ENSG00000166278	ENSMUSG00000024371
UniProt	P06681	P21180
RefSeq (mRNA)	NM_000063	NM_013484
RefSeq (protein)	NP_000054	NP_038512
Location (UCSC)	Chr 6: 31.9 – 31.95 Mb	Chr 17: 34.86 – 34.9 Mb
PubMed search

Complement C2 is a protein that in humans is encoded by the C2 gene.^[1] The protein encoded by this gene is part of the classical pathway of complement system, acting as a multi-domain serine protease. Deficiency of C2 has been associated with certain autoimmune diseases.^[1]

Function

In the classical and lectin pathways of complement activation, formation of the C3-convertase and C5-convertases requires binding of C2 to an activated surface-bound C4b in the presence of Mg²⁺; the resultant C4bC2 complex is then cleaved by C1s or MASP2 into C2a and C2b. It is thought that cleavage of C2 by C1s, while bound to C4b. results into a conformational rotation of C2a whereas the released C2b fragment may retain most of its original structure. C2a is the larger, enzymatically active fragment which is incorporated into the C3 convertase in this pathway, C4b2. C2b is released into the fluid phase.^[2]

References

1. "Entrez Gene: C2 complement component 2".
2. Takeuchi E, Doi T, Shimada T, Muso E, Maruyama N, Yoshida H (Feb 1989). "Retroviral gp70 antigen in spontaneous mesangial glomerulonephritis of ddY mice". Kidney International 35 (2): 638–46. doi:10.1038/ki.1989.33. PMC 2651757. PMID 19237749.

Further reading

• Bartholomew WR, Shanahan TC (1991). "Complement components and receptors: deficiencies and disease associations". Immunology Series 52: 33–51. PMID 2091785.
• Campbell RD (Jan 1987). "The molecular genetics and polymorphism of C2 and factor B". British Medical Bulletin 43 (1): 37–49. PMID 3315100.
• Yu CY (1999). "Molecular genetics of the human MHC complement gene cluster". Experimental and Clinical Immunogenetics 15 (4): 213–30. doi:10.1159/000019075. PMID 10072631.
• Lutsenko SM, Kharchenko VG, Bachurin VI, Lomakin MM (Feb 1976). "[Circulating blood volume and regional hemodynamics in acute gastrointestinal hemorrhage]". Sovetskaia Meditsina (2): 38–41. PMID 1084023.
• Zhu ZB, Hsieh SL, Bentley DR, Campbell RD, Volanakis JE (Jun 1992). "A variable number of tandem repeats locus within the human complement C2 gene is associated with a retroposon derived from a human endogenous retrovirus". The Journal of Experimental Medicine 175 (6): 1783–7. doi:10.1084/jem.175.6.1783. PMC 2119228. PMID 1350302.
• Lappin DF, Guc D, Hill A, McShane T, Whaley K (Jan 1992). "Effect of interferon-gamma on complement gene expression in different cell types". The Biochemical Journal 281 (Pt 2): 437–42. doi:10.1042/bj2810437. PMC 1130704. PMID 1531292.
• Johnson CA, Densen P, Hurford RK, Colten HR, Wetsel RA (May 1992). "Type I human complement C2 deficiency. A 28-base pair gene deletion causes skipping of exon 6 during RNA splicing". The Journal of Biological Chemistry 267 (13): 9347–53. PMID 1577763.
• Lappin DF, Birnie GD, Whaley K (Nov 1990). "Interferon-mediated transcriptional and post-transcriptional modulation of complement gene expression in human monocytes". European Journal of Biochemistry / FEBS 194 (1): 177–84. doi:10.1111/j.1432-1033.1990.tb19443.x. PMID 1701385.
• Horiuchi T, Macon KJ, Kidd VJ, Volanakis JE (Mar 1989). "cDNA cloning and expression of human complement component C2". Journal of Immunology 142 (6): 2105–11. PMID 2493504.
• Cole FS, Whitehead AS, Auerbach HS, Lint T, Zeitz HJ, Kilbridge P, Colten HR (Jul 1985). "The molecular basis for genetic deficiency of the second component of human complement". The New England Journal of Medicine 313 (1): 11–6. doi:10.1056/NEJM198507043130103. PMID 2582254.
• Bentley DR (Oct 1986). "Primary structure of human complement component C2. Homology to two unrelated protein families". The Biochemical Journal 239 (2): 339–45. doi:10.1042/bj2390339. PMC 1147286. PMID 2949737.
• Bentley DR, Campbell RD, Cross SJ (1985). "DNA polymorphism of the C2 locus". Immunogenetics 22 (4): 377–90. doi:10.1007/BF00430921. PMID 2997031.
• Kam CM, McRae BJ, Harper JW, Niemann MA, Volanakis JE, Powers JC (Mar 1987). "Human complement proteins D, C2, and B. Active site mapping with peptide thioester substrates". The Journal of Biological Chemistry 262 (8): 3444–51. PMID 3546307.
• Wu LC, Morley BJ, Campbell RD (Jan 1987). "Cell-specific expression of the human complement protein factor B gene: evidence for the role of two distinct 5'-flanking elements". Cell 48 (2): 331–42. doi:10.1016/0092-8674(87)90436-3. PMID 3643061.
• Gagnon J (Sep 1984). "Structure and activation of complement components C2 and factor B". Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences 306 (1129): 301–9. doi:10.1098/rstb.1984.0091. PMID 6149575.
• Bentley DR, Porter RR (Feb 1984). "Isolation of cDNA clones for human complement component C2". Proceedings of the National Academy of Sciences of the United States of America 81 (4): 1212–5. doi:10.1073/pnas.81.4.1212. PMC 344796. PMID 6199794.
• Parkes C, Gagnon J, Kerr MA (Jul 1983). "The reaction of iodine and thiol-blocking reagents with human complement components C2 and factor B. Purification and N-terminal amino acid sequence of a peptide from C2a containing a free thiol group". The Biochemical Journal 213 (1): 201–9. doi:10.1042/bj2130201. PMC 1152109. PMID 6555044.
• Kerr MA, Gagnon J (Jul 1982). "The purification and properties of the second component of guinea-pig complement". The Biochemical Journal 205 (1): 59–67. doi:10.1042/bj2050059. PMC 1158446. PMID 6922702.

External links

• Complement 2 at the US National Library of Medicine Medical Subject Headings (MeSH)