This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.

Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.

4mhe

From Proteopedia

(Difference between revisions)

Jump to: navigation, search

Revision as of 17:34, 9 March 2017

Crystal structure of CC-chemokine 18

Structural highlights

4mhe is a 4 chain structure. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[CCL18_HUMAN] Chemotactic factor that attracts lymphocytes but not monocytes or granulocytes. May be involved in B-cell migration into B-cell follicles in lymph nodes. Attracts naive T-lymphocytes toward dendritic cells and activated macrophages in lymph nodes, has chemotactic activity for naive T-cells, CD4+ and CD8+ T-cells and thus may play a role in both humoral and cell-mediated immunity responses.^[1] ^[2]

Publication Abstract from PubMed

CC chemokine ligands (CCLs) are 8- to 14-kDa signaling proteins involved in diverse immune functions. While CCLs share similar tertiary structures, oligomerization produces highly diverse quaternary structures that protect chemokines from proteolytic degradation and modulate their functions. CCL18 is closely related to CCL3 and CCL4 with respect to both protein sequence and genomic location, yet CCL18 has distinct biochemical and biophysical properties. Here, we report a crystal structure of human CCL18 and its oligomerization states in solution based on crystallographic and small-angle X-ray scattering analyses. Our data show that CCL18 adopts an alpha-helical conformation at its N-terminus that weakens its dimerization, explaining CCL18's preference for the monomeric state. Multiple contacts between monomers allow CCL18 to reversibly form a unique open-ended oligomer different from those of CCL3, CCL4, and CCL5. Furthermore, these differences hinge on proline 8, which is conserved in CCL3 and CCL4 but is replaced by lysine in human CCL18. Our structural analyses suggest that a mutation of proline 8 to alanine stabilizes a type 1 beta-turn at the N-terminus of CCL4 to prevent dimerization but prevents dimers from making key contacts with each other in CCL3. Thus, the P8A mutation induces depolymerization of CCL3 and CCL4 by distinct mechanisms. Finally, we used structural, biochemical, and functional analyses to unravel why insulin-degrading enzyme degrades CCL3 and CCL4 but not CCL18. Our results elucidate the molecular basis for the oligomerization of three closely related CC chemokines and suggest how oligomerization shapes CCL chemokine function.

Structures of human CCL18, CCL3, and CCL4 reveal molecular determinants for quaternary structures and sensitivity to insulin-degrading enzyme.,Liang WG, Ren M, Zhao F, Tang WJ J Mol Biol. 2015 Mar 27;427(6 Pt B):1345-58. doi: 10.1016/j.jmb.2015.01.012. Epub, 2015 Jan 28. PMID:25636406^[3]

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

References

↑ Schutyser E, Struyf S, Wuyts A, Put W, Geboes K, Grillet B, Opdenakker G, Van Damme J. Selective induction of CCL18/PARC by staphylococcal enterotoxins in mononuclear cells and enhanced levels in septic and rheumatoid arthritis. Eur J Immunol. 2001 Dec;31(12):3755-62. PMID:11745396 doi:http://dx.doi.org/10.1002/1521-4141(200112)31:12<3755::AID-IMMU3755>3.0.CO;2-O
↑ Schutyser E, Struyf S, Proost P, Opdenakker G, Laureys G, Verhasselt B, Peperstraete L, Van de Putte I, Saccani A, Allavena P, Mantovani A, Van Damme J. Identification of biologically active chemokine isoforms from ascitic fluid and elevated levels of CCL18/pulmonary and activation-regulated chemokine in ovarian carcinoma. J Biol Chem. 2002 Jul 5;277(27):24584-93. Epub 2002 Apr 26. PMID:11978786 doi:http://dx.doi.org/10.1074/jbc.M112275200
↑ Liang WG, Ren M, Zhao F, Tang WJ. Structures of human CCL18, CCL3, and CCL4 reveal molecular determinants for quaternary structures and sensitivity to insulin-degrading enzyme. J Mol Biol. 2015 Mar 27;427(6 Pt B):1345-58. doi: 10.1016/j.jmb.2015.01.012. Epub, 2015 Jan 28. PMID:25636406 doi:http://dx.doi.org/10.1016/j.jmb.2015.01.012

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

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/4mhe"

Categories: Liang, W G | Tang, W J | Greek key shape | Immune system

@@ Line 1: / Line 1: @@
 ==Crystal structure of CC-chemokine 18==
 <StructureSection load='4mhe' size='340' side='right' caption='[[4mhe]], [[Resolution|resolution]] 2.10&Aring;' scene=''>
@@ Line 4: / Line 5: @@
 <table><tr><td colspan='2'>[[4mhe]] is a 4 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4MHE OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4MHE FirstGlance]. <br>
 </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=ACT:ACETATE+ION'>ACT</scene></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=4mhe FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4mhe OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4mhe RCSB], [http://www.ebi.ac.uk/pdbsum/4mhe 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=4mhe FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4mhe OCA], [http://pdbe.org/4mhe PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=4mhe RCSB], [http://www.ebi.ac.uk/pdbsum/4mhe PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=4mhe ProSAT]</span></td></tr>
 </table>
 == Function ==
@@ Line 16: / Line 17: @@
 From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
 </div>
+<div class="pdbe-citations 4mhe" style="background-color:#fffaf0;"></div>
 == References ==
 <references/>

4mhe

From Proteopedia

Revision as of 17:34, 9 March 2017

Crystal structure of CC-chemokine 18

Structural highlights

Function

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

Personal tools

Navigation

Search

Toolbox