View source for C1QA

{{cs1 config|name-list-style=vanc}}
{{Short description|Protein-coding gene in the species Homo sapiens}}
{{Infobox_gene}}
'''Complement C1q subcomponent subunit A''' is a [[protein]] that in humans is encoded by the ''C1QA'' [[gene]].<ref name="pmid1537612">{{cite journal | vauthors = Sellar GC, Cockburn D, Reid KB | title = Localization of the gene cluster encoding the A, B, and C chains of human C1q to 1p34.1-1p36.3 | journal = Immunogenetics | volume = 35 | issue = 3 | pages = 214–6 |date=Mar 1992 | pmid = 1537612 | doi =  10.1007/bf00185116| s2cid = 26894430 }}</ref>
This gene encodes a major constituent of the human [[complement system]] subcomponent [[C1Q complex|C1q]].
C1q associates with C1r and C1s in order to yield the first component of the serum complement system. Deficiency of C1q has been associated with lupus erythematosus and glomerulonephritis. C1q is composed of 18 polypeptide chains: six A-chains, six B-chains, and six C-chains. Each chain contains a collagen-like region located near the N terminus and a C-terminal globular region. The A-, B-, and C-chains are arranged in the order A-C-B on chromosome 1. This gene encodes the A-chain polypeptide of human complement subcomponent C1q.<ref name="entrez">{{cite web | title = Entrez Gene: C1QA complement component 1, q subcomponent, A chain| url = https://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=712}}</ref>
==References==
{{reflist}}
==External links==
* {{UCSC gene info|C1QA}}
==Further reading==
{{refbegin | 2}}
*{{cite journal  | author=Petry F |title=Molecular basis of hereditary C1q deficiency. |journal=Immunobiology |volume=199 |issue= 2 |pages= 286–94 |year= 1999 |pmid= 9777412 |doi=  10.1016/s0171-2985(98)80033-8}}
*{{cite journal  | vauthors=Thielens NM, Tacnet-Delorme P, Arlaud GJ |title=Interaction of C1q and mannan-binding lectin with viruses. |journal=Immunobiology |volume=205 |issue= 4–5 |pages= 563–74 |year= 2003 |pmid= 12396016 |doi=10.1078/0171-2985-00155  }}
*{{cite journal  | author=Reid KB |title=Isolation, by partial pepsin digestion, of the three collagen-like regions present in subcomponent Clq of the first component of human complement |journal=Biochem. J. |volume=155 |issue= 1 |pages= 5–17 |year= 1976 |doi=10.1042/bj1550005 |pmid= 7240 | pmc=1172796  }}
*{{cite journal  | author=Reid KB |title=Complete amino acid sequences of the three collagen-like regions present in subcomponent C1q of the first component of human complement |journal=Biochem. J. |volume=179 |issue= 2 |pages= 367–71 |year= 1979 |doi=10.1042/bj1790367 |pmid= 486087 | pmc=1186634  }}
*{{cite journal  | vauthors=Krumdieck R, Höök M, Rosenberg LC, Volanakis JE |title=The proteoglycan decorin binds C1q and inhibits the activity of the C1 complex |journal=J. Immunol. |volume=149 |issue= 11 |pages= 3695–701 |year= 1992 |doi=10.4049/jimmunol.149.11.3695 |pmid= 1431141 |doi-access=free }}
*{{cite journal  | vauthors=Sellar GC, Blake DJ, Reid KB |title=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 |journal=Biochem. J. |volume=274 |issue=  2|pages= 481–90 |year= 1991 |pmid= 1706597 |doi=  10.1042/bj2740481| pmc=1150164  }}
*{{cite journal  | vauthors=Ebenbichler CF, Thielens NM, Vornhagen R |title=Human immunodeficiency virus type 1 activates the classical pathway of complement by direct C1 binding through specific sites in the transmembrane glycoprotein gp41 |journal=J. Exp. Med. |volume=174 |issue= 6 |pages= 1417–24 |year= 1992 |pmid= 1744579 |doi=10.1084/jem.174.6.1417  | pmc=2119058  |display-authors=etal}}
*{{cite journal  | vauthors=Su H, Boackle RJ |title=Interaction of the envelope glycoprotein of human immunodeficiency virus with C1q and fibronectin under conditions present in human saliva |journal=Mol. Immunol. |volume=28 |issue= 8 |pages= 811–7 |year= 1991 |pmid= 1875953 |doi=10.1016/0161-5890(91)90044-K  }}
*{{cite journal  | vauthors=Busby TF, Ingham KC |title=NH2-terminal calcium-binding domain of human complement C1s- mediates the interaction of C1r- with C1q |journal=Biochemistry |volume=29 |issue= 19 |pages= 4613–8 |year= 1990 |pmid= 2372546 |doi=10.1021/bi00471a016  }}
*{{cite journal  | vauthors=Bing DH, Almeda S, Isliker H |title=Fibronectin binds to the C1q component of complement |journal=Proc. Natl. Acad. Sci. U.S.A. |volume=79 |issue= 13 |pages= 4198–201 |year= 1982 |pmid= 6981115 |doi=10.1073/pnas.79.13.4198  | pmc=346605  |bibcode=1982PNAS...79.4198B |display-authors=etal|doi-access=free }}
*{{cite journal  | vauthors=Reid KB, Gagnon J, Frampton J |title=Completion of the amino acid sequences of the A and B chains of subcomponent C1q of the first component of human complement |journal=Biochem. J. |volume=203 |issue= 3 |pages= 559–69 |year= 1982 |doi=10.1042/bj2030559 |pmid= 6981411 | pmc=1158269  }}
*{{cite journal  | vauthors=Stoiber H, Thielens NM, Ebenbichler C |title=The envelope glycoprotein of HIV-1 gp120 and human complement protein C1q bind to the same peptides derived from three different regions of gp41, the transmembrane glycoprotein of HIV-1, and share antigenic homology |journal=Eur. J. Immunol. |volume=24 |issue= 2 |pages= 294–300 |year= 1994 |pmid= 7507842 |doi=10.1002/eji.1830240203  |s2cid=24908489 |display-authors=etal}}
*{{cite journal  | vauthors=Prohászka Z, Hidvégi T, Ujhelyi E |title=Interaction of complement and specific antibodies with the external glycoprotein 120 of HIV-1 |journal=Immunology |volume=85 |issue= 2 |pages= 184–9 |year= 1995 |pmid= 7642209 | pmc=1383879  |display-authors=etal}}
*{{cite journal  | vauthors=Stoiber H, Ebenbichler CF, Thielens NM |title=HIV-1 rsgp41 depends on calcium for binding of human c1q but not for binding of gp120 |journal=Mol. Immunol. |volume=32 |issue= 5 |pages= 371–4 |year= 1995 |pmid= 7739575 |doi=10.1016/0161-5890(94)00156-U  |display-authors=etal}}
*{{cite journal  | vauthors=Gulati P, Guc D, Lemercier C |title=Expression of the components and regulatory proteins of the classical pathway of complement in normal and diseased synovium |journal=Rheumatol. Int. |volume=14 |issue= 1 |pages= 13–9 |year= 1994 |pmid= 7939135 |doi=10.1007/BF00302666  |s2cid=2144366 |display-authors=etal}}
*{{cite journal  | vauthors=Gulati P, Lemercier C, Guc D |title=Regulation of the synthesis of C1 subcomponents and C1-inhibitor |journal=Behring Inst. Mitt. |issue= 93 |pages= 196–203 |year= 1994 |pmid= 8172568 |display-authors=etal}}
*{{cite journal  | vauthors=Ghebrehiwet B, Lim BL, Peerschke EI |title=Isolation, cDNA cloning, and overexpression of a 33-kD cell surface glycoprotein that binds to the globular "heads" of C1q |journal=J. Exp. Med. |volume=179 |issue= 6 |pages= 1809–21 |year= 1994 |pmid= 8195709 |doi=10.1084/jem.179.6.1809  | pmc=2191527  |display-authors=etal|url=http://hub.hku.hk/bitstream/10722/53488/3/je17961809.pdf}}
*{{cite journal  | vauthors=Thielens NM, Bally IM, Ebenbichler CF |title=Further characterization of the interaction between the C1q subcomponent of human C1 and the transmembrane envelope glycoprotein gp41 of HIV-1 |journal=J. Immunol. |volume=151 |issue= 11 |pages= 6583–92 |year= 1994 |doi=10.4049/jimmunol.151.11.6583 |pmid= 8245486 |display-authors=etal|doi-access=free }}
*{{cite journal  | vauthors=Hidvégi T, Prohászka Z, Ujhelyi E |title=Studies on the mechanism of complement-mediated inhibition of antibody binding to HIV gp41 |journal=Clin. Exp. Immunol. |volume=94 |issue= 3 |pages= 490–3 |year= 1994 |pmid= 8252810 |doi=  10.1111/j.1365-2249.1993.tb08223.x| pmc=1534428  |display-authors=etal}}
{{refend}}
{{PDB Gallery|geneid=712}}
{{gene-1-stub}}