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5hkj

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Revision as of 03:59, 30 August 2017

Single Chain Recombinant Globular Head of the Complement System Protein C1q

Structural highlights

5hkj is a 1 chain structure. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:	,
Related:	5hzf
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Disease

[C1QA_HUMAN] Defects in C1QA are a cause of complement component C1q deficiency (C1QD) [MIM:613652]. A rare defect resulting in C1 deficiency and impaired activation of the complement classical pathway. C1 deficiency generally leads to severe immune complex disease with features of systemic lupus erythematosus and glomerulonephritis.

Function

[C1QA_HUMAN] 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 Ca(2+)-dependent C1r(2)C1s(2) 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.

Publication Abstract from PubMed

Complement C1q is a soluble pattern recognition molecule comprising six heterotrimeric subunits assembled from three polypeptide chains (A-C). Each heterotrimer forms a collagen-like stem prolonged by a globular recognition domain. These recognition domains sense a wide variety of ligands, including pathogens and altered-self components. Ligand recognition is either direct or mediated by immunoglobulins or pentraxins. Multivalent binding of C1q to its targets triggers immune effector mechanisms mediated via its collagen-like stems. The induced immune response includes activation of the classical complement pathway and enhancement of the phagocytosis of the recognized target. We report here, the first production of a single-chain recombinant form of human C1q globular region (C1q-scGR). The three monomers have been linked in tandem to generate a single continuous polypeptide, based on a strategy previously used for adiponectin, a protein structurally related to C1q. The resulting C1q-scGR protein was produced at high yield in stably transfected 293-F mammalian cells. Recombinant C1q-scGR was correctly folded, as demonstrated by its X-ray crystal structure solved at a resolution of 1.35 A. Its interaction properties were assessed by surface plasmon resonance analysis using the following physiological C1q ligands: the receptor for C1q globular heads, the long pentraxin PTX3, calreticulin, and heparin. The 3D structure and the binding properties of C1q-scGR were similar to those of the three-chain fragment generated by collagenase digestion of serum-derived C1q. Comparison of the interaction properties of the fragments with those of native C1q provided insights into the avidity component associated with the hexameric assembly of C1q. The interest of this functional recombinant form of the recognition domains of C1q in basic research and its potential biomedical applications are discussed.

Structural and Functional Characterization of a Single-Chain Form of the Recognition Domain of Complement Protein C1q.,Moreau C, Bally I, Chouquet A, Bottazzi B, Ghebrehiwet B, Gaboriaud C, Thielens N Front Immunol. 2016 Mar 2;7:79. doi: 10.3389/fimmu.2016.00079. eCollection 2016. PMID:26973654^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Moreau C, Bally I, Chouquet A, Bottazzi B, Ghebrehiwet B, Gaboriaud C, Thielens N. Structural and Functional Characterization of a Single-Chain Form of the Recognition Domain of Complement Protein C1q. Front Immunol. 2016 Mar 2;7:79. doi: 10.3389/fimmu.2016.00079. eCollection 2016. PMID:26973654 doi:http://dx.doi.org/10.3389/fimmu.2016.00079

1 Structural highlights
2 Disease
3 Function
4 Publication Abstract from PubMed
5 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/5hkj"

@@ Line 6: / Line 6: @@
 </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene></td></tr>
 <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[5hzf|5hzf]]</td></tr>
-<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5hkj FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5hkj OCA], [http://pdbe.org/5hkj PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5hkj RCSB], [http://www.ebi.ac.uk/pdbsum/5hkj PDBsum]</span></td></tr>
+<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5hkj FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5hkj OCA], [http://pdbe.org/5hkj PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5hkj RCSB], [http://www.ebi.ac.uk/pdbsum/5hkj PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=5hkj ProSAT]</span></td></tr>
 </table>
 == Disease ==

5hkj

From Proteopedia

Revision as of 03:59, 30 August 2017

Single Chain Recombinant Globular Head of the Complement System Protein C1q

Structural highlights

Disease

Function

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

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