4LSD

Myokine structure


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.28 Å
  • R-Value Free: 0.236 
  • R-Value Work: 0.224 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

The structure of irisin reveals a novel intersubunit beta-sheet fibronectin type III (FNIII) dimer: implications for receptor activation.

Schumacher, M.A.Chinnam, N.Ohashi, T.Shah, R.S.Erickson, H.P.

(2013) J.Biol.Chem. 288: 33738-33744

  • DOI: 10.1074/jbc.M113.516641

  • PubMed Abstract: 
  • Irisin was recently identified as a putative myokine that is induced by exercise. Studies suggest that it is produced by cleavage of the FNDC5 (fibronectin domain-containing protein 5) receptor; irisin corresponds to the extracellular receptor ectodo ...

    Irisin was recently identified as a putative myokine that is induced by exercise. Studies suggest that it is produced by cleavage of the FNDC5 (fibronectin domain-containing protein 5) receptor; irisin corresponds to the extracellular receptor ectodomain. Data suggesting that irisin stimulates white-to-brown fat conversion have led to the hypothesis that it does so by binding an unknown receptor, thus functioning as a myokine. As brown fat promotes energy dissipation, myokines that elicit the transformation of white to brown fat have potentially profound benefits in the treatment of obesity and metabolic disorders. Understanding the molecular basis for such exercise-induced phenomena is thus of considerable interest. Moreover, FNDC5-like receptors are highly conserved and have been shown to be critical for neuronal development. However, the structural and molecular mechanisms utilized by these proteins are currently unknown. Here, we describe the crystal structure and biochemical characterization of the FNDC5 ectodomain, corresponding to the irisin myokine. The 2.28 Å structure shows that irisin consists of an N-terminal fibronectin III (FNIII)-like domain attached to a flexible C-terminal tail. Strikingly, the FNIII-like domain forms a continuous intersubunit β-sheet dimer, previously unobserved for any FNIII protein. Biochemical data confirm that irisin is a dimer and that dimerization is unaffected by glycosylation. This finding suggests a possible mechanism for receptor activation by the irisin domain as a preformed myokine dimer ligand or as a paracrine or autocrine dimerization module on FNDC5-like receptors.


    Organizational Affiliation

    From the Departments of Biochemistry and.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Fibronectin type III domain-containing protein 5
A, B, C, D, E, F, G, H
99Homo sapiensMutation(s): 0 
Gene Names: FNDC5 (FRCP2)
Find proteins for Q8NAU1 (Homo sapiens)
Go to Gene View: FNDC5
Go to UniProtKB:  Q8NAU1
Small Molecules
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
MSE
Query on MSE
A, B, C, D, E, F, G, H
L-PEPTIDE LINKINGC5 H11 N O2 SeMET
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.28 Å
  • R-Value Free: 0.236 
  • R-Value Work: 0.224 
  • Space Group: P 41 21 2
Unit Cell:
Length (Å)Angle (°)
a = 93.200α = 90.00
b = 93.200β = 90.00
c = 284.900γ = 90.00
Software Package:
Software NamePurpose
ADSCdata collection
CNSrefinement
MOSFLMdata reduction
SCALAdata scaling
CNSphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2013-10-16
    Type: Initial release
  • Version 1.1: 2013-10-23
    Type: Database references
  • Version 1.2: 2014-02-12
    Type: Database references