2N0X

Three dimensional structure of EPI-X4, a human albumin-derived peptide that regulates innate immunity through the CXCR4/CXCL12 chemotactic axis and antagonizes HIV-1 entry


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the least restraint violations 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Discovery and characterization of an endogenous CXCR4 antagonist.

Zirafi, O.Kim, K.A.Standker, L.Mohr, K.B.Sauter, D.Heigele, A.Kluge, S.F.Wiercinska, E.Chudziak, D.Richter, R.Moepps, B.Gierschik, P.Vas, V.Geiger, H.Lamla, M.Weil, T.Burster, T.Zgraja, A.Daubeuf, F.Frossard, N.Hachet-Haas, M.Heunisch, F.Reichetzeder, C.Galzi, J.L.Perez-Castells, J.Canales-Mayordomo, A.Jimenez-Barbero, J.Gimenez-Gallego, G.Schneider, M.Shorter, J.Telenti, A.Hocher, B.Forssmann, W.G.Bonig, H.Kirchhoff, F.Munch, J.

(2015) Cell Rep 11: 737-747

  • DOI: 10.1016/j.celrep.2015.03.061

  • PubMed Abstract: 
  • CXCL12-CXCR4 signaling controls multiple physiological processes and its dysregulation is associated with cancers and inflammatory diseases. To discover as-yet-unknown endogenous ligands of CXCR4, we screened a blood-derived peptide library for inhib ...

    CXCL12-CXCR4 signaling controls multiple physiological processes and its dysregulation is associated with cancers and inflammatory diseases. To discover as-yet-unknown endogenous ligands of CXCR4, we screened a blood-derived peptide library for inhibitors of CXCR4-tropic HIV-1 strains. This approach identified a 16 amino acid fragment of serum albumin as an effective and highly specific CXCR4 antagonist. The endogenous peptide, termed EPI-X4, is evolutionarily conserved and generated from the highly abundant albumin precursor by pH-regulated proteases. EPI-X4 forms an unusual lasso-like structure and antagonizes CXCL12-induced tumor cell migration, mobilizes stem cells, and suppresses inflammatory responses in mice. Furthermore, the peptide is abundant in the urine of patients with inflammatory kidney diseases and may serve as a biomarker. Our results identify EPI-X4 as a key regulator of CXCR4 signaling and introduce proteolysis of an abundant precursor protein as an alternative concept for chemokine receptor regulation.


    Organizational Affiliation

    Institute of Molecular Virology, University of Ulm, 89081 Ulm, Germany.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Serum albumin
A
16Homo sapiensGene Names: ALB
Find proteins for P02768 (Homo sapiens)
Go to Gene View: ALB
Go to UniProtKB:  P02768
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the least restraint violations 

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2015-04-29
    Type: Initial release
  • Version 1.1: 2015-05-13
    Type: Database references
  • Version 1.2: 2015-05-20
    Type: Database references